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Zhang C, Liu L, Dai J, Liu X, He W, Chan Y, Xie Y, Chi F, Liang X. XTransCT: ultra-fast volumetric CT reconstruction using two orthogonal x-ray projections for image-guided radiation therapy via a transformer network. Phys Med Biol 2024; 69:085010. [PMID: 38471171 DOI: 10.1088/1361-6560/ad3320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Accepted: 03/12/2024] [Indexed: 03/14/2024]
Abstract
Objective.The aim of this study was to reconstruct volumetric computed tomography (CT) images in real-time from ultra-sparse two-dimensional x-ray projections, facilitating easier navigation and positioning during image-guided radiation therapy.Approach.Our approach leverages a voxel-sapce-searching Transformer model to overcome the limitations of conventional CT reconstruction techniques, which require extensive x-ray projections and lead to high radiation doses and equipment constraints.Main results.The proposed XTransCT algorithm demonstrated superior performance in terms of image quality, structural accuracy, and generalizability across different datasets, including a hospital set of 50 patients, the large-scale public LIDC-IDRI dataset, and the LNDb dataset for cross-validation. Notably, the algorithm achieved an approximately 300% improvement in reconstruction speed, with a rate of 44 ms per 3D image reconstruction compared to former 3D convolution-based methods.Significance.The XTransCT architecture has the potential to impact clinical practice by providing high-quality CT images faster and with substantially reduced radiation exposure for patients. The model's generalizability suggests it has the potential applicable in various healthcare settings.
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Affiliation(s)
- Chulong Zhang
- Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, Guangdong, People's Republic of China
| | - Lin Liu
- Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, Guangdong, People's Republic of China
| | - Jingjing Dai
- Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, Guangdong, People's Republic of China
| | - Xuan Liu
- Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, Guangdong, People's Republic of China
| | - Wenfeng He
- Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, Guangdong, People's Republic of China
| | - Yinping Chan
- Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, Guangdong, People's Republic of China
| | - Yaoqin Xie
- Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, Guangdong, People's Republic of China
| | - Feng Chi
- State Key Laboratory of Oncology in South China, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-sen University Cancer Center, 510060, People's Republic of China
| | - Xiaokun Liang
- Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, Guangdong, People's Republic of China
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Liu SZ, Herbst M, Schaefer J, Weber T, Vogt S, Ritschl L, Kappler S, Kawcak CE, Stewart HL, Siewerdsen JH, Zbijewski W. Feasibility of bone marrow edema detection using dual-energy cone-beam computed tomography. Med Phys 2024; 51:1653-1673. [PMID: 38323878 DOI: 10.1002/mp.16962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 12/17/2023] [Accepted: 01/16/2024] [Indexed: 02/08/2024] Open
Abstract
BACKGROUND Dual-energy (DE) detection of bone marrow edema (BME) would be a valuable new diagnostic capability for the emerging orthopedic cone-beam computed tomography (CBCT) systems. However, this imaging task is inherently challenging because of the narrow energy separation between water (edematous fluid) and fat (health yellow marrow), requiring precise artifact correction and dedicated material decomposition approaches. PURPOSE We investigate the feasibility of BME assessment using kV-switching DE CBCT with a comprehensive CBCT artifact correction framework and a two-stage projection- and image-domain three-material decomposition algorithm. METHODS DE CBCT projections of quantitative BME phantoms (water containers 100-165 mm in size with inserts presenting various degrees of edema) and an animal cadaver model of BME were acquired on a CBCT test bench emulating the standard wrist imaging configuration of a Multitom Rax twin robotic x-ray system. The slow kV-switching scan protocol involved a 60 kV low energy (LE) beam and a 120 kV high energy (HE) beam switched every 0.5° over a 200° angular span. The DE CBCT data preprocessing and artifact correction framework consisted of (i) projection interpolation onto matched LE and HE projections views, (ii) lag and glare deconvolutions, and (iii) efficient Monte Carlo (MC)-based scatter correction. Virtual non-calcium (VNCa) images for BME detection were then generated by projection-domain decomposition into an Aluminium (Al) and polyethylene basis set (to remove beam hardening) followed by three-material image-domain decomposition into water, Ca, and fat. Feasibility of BME detection was quantified in terms of VNCa image contrast and receiver operating characteristic (ROC) curves. Robustness to object size, position in the field of view (FOV) and beam collimation (varied 20-160 mm) was investigated. RESULTS The MC-based scatter correction delivered > 69% reduction of cupping artifacts for moderate to wide collimations (> 80 mm beam width), which was essential to achieve accurate DE material decomposition. In a forearm-sized object, a 20% increase in water concentration (edema) of a trabecular bone-mimicking mixture presented as ∼15 HU VNCa contrast using 80-160 mm beam collimations. The variability with respect to object position in the FOV was modest (< 15% coefficient of variation). The areas under the ROC curve were > 0.9. A femur-sized object presented a somewhat more challenging task, resulting in increased sensitivity to object positioning at 160 mm collimation. In animal cadaver specimens, areas of VNCa enhancement consistent with BME were observed in DE CBCT images in regions of MRI-confirmed edema. CONCLUSION Our results indicate that the proposed artifact correction and material decomposition pipeline can overcome the challenges of scatter and limited spectral separation to achieve relatively accurate and sensitive BME detection in DE CBCT. This study provides an important baseline for clinical translation of musculoskeletal DE CBCT to quantitative, point-of-care bone health assessment.
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Affiliation(s)
- Stephen Z Liu
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland, USA
| | | | | | | | | | | | | | - Christopher E Kawcak
- Department of Clinical Sciences, Colorado State University College of Veterinary Medicine and Biomedical Sciences, Fort Collins, Colorado, USA
| | - Holly L Stewart
- Department of Clinical Sciences, Colorado State University College of Veterinary Medicine and Biomedical Sciences, Fort Collins, Colorado, USA
| | - Jeffrey H Siewerdsen
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland, USA
- Department of Imaging Physics, MD Anderson Cancer Center, Houston, Texas, USA
| | - Wojciech Zbijewski
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland, USA
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Xu D, Xie F, Zhang J, Chen H, Chen Z, Guan Z, Hou G, Ji C, Li H, Li M, Li W, Li X, Li Y, Lian H, Liao J, Liu D, Luo Z, Ouyang H, Shen Y, Shi Y, Tang C, Wan N, Wang T, Wang H, Wang H, Wang J, Wu X, Xia Y, Xiao K, Xu W, Xu F, Yang H, Yang J, Ye T, Ye X, Yu P, Zhang N, Zhang P, Zhang Q, Zhao Q, Zheng X, Zou J, Chen E, Sun J. Chinese expert consensus on cone-beam CT-guided diagnosis, localization and treatment for pulmonary nodules. Thorac Cancer 2024; 15:582-597. [PMID: 38337087 PMCID: PMC10912555 DOI: 10.1111/1759-7714.15222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Accepted: 01/07/2024] [Indexed: 02/12/2024] Open
Abstract
Cone-beam computed tomography (CBCT) system can provide real-time 3D images and fluoroscopy images of the region of interest during the operation. Some systems can even offer augmented fluoroscopy and puncture guidance. The use of CBCT for interventional pulmonary procedures has grown significantly in recent years, and numerous clinical studies have confirmed the technology's efficacy and safety in the diagnosis, localization, and treatment of pulmonary nodules. In order to optimize and standardize the technical specifications of CBCT and guide its application in clinical practice, the consensus statement has been organized and written in a collaborative effort by the Professional Committee on Interventional Pulmonology of China Association for Promotion of Health Science and Technology.
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Affiliation(s)
- Dongyang Xu
- Department of Respiratory Endoscopy, Shanghai Chest HospitalShanghai Jiao Tong University School of MedicineShanghaiChina
- Department of Respiratory and Critical Care Medicine, Shanghai Chest HospitalShanghai Jiao Tong University School of MedicineShanghaiChina
- Shanghai Engineering Research Center of Respiratory EndoscopyShanghaiChina
| | - Fangfang Xie
- Department of Respiratory Endoscopy, Shanghai Chest HospitalShanghai Jiao Tong University School of MedicineShanghaiChina
- Department of Respiratory and Critical Care Medicine, Shanghai Chest HospitalShanghai Jiao Tong University School of MedicineShanghaiChina
- Shanghai Engineering Research Center of Respiratory EndoscopyShanghaiChina
| | - Jisong Zhang
- Department of Pulmonary and Critical Care Medicine, Regional Medical Center for National Institute of Respiratory DiseaseSir Run Run Shaw Hospital of Zhejiang UniversityHangzhouChina
| | - Hong Chen
- Department of Pulmonary and Critical Care MedicineSecond Affiliated Hospital of Harbin Medical UniversityHarbinChina
| | - Zhongbo Chen
- Department of Pulmonary and Critical Care Medicine, The Affiliated Hospital of Medical SchoolNingbo UniversityNingboChina
| | - Zhenbiao Guan
- Department of Respiration, Changhai HospitalNaval Medical UniversityShanghaiChina
| | - Gang Hou
- Department of Pulmonary and Critical Care Medicine, China‐Japan Friendship HospitalBeijingChina
| | - Cheng Ji
- Department of Respiratory and Critical Care MedicineThe First Affiliated Hospital of Soochow UniversitySuzhouChina
| | - Haitao Li
- Department of Respiratory and Critical Care MedicineThe Second Hospital of Hebei Medical UniversityShijiazhuangHebeiChina
| | - Manxiang Li
- Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital of Xi'an Jiaotong UniversityXi'anChina
| | - Wei Li
- Department of Respiratory DiseaseThe First Affiliated Hospital of Bengbu Medical CollegeBengbuChina
| | - Xuan Li
- Department of Respiratory Medicine, Shanghai Tenth People's HospitalTongji University School of MedicineShanghaiChina
| | - Yishi Li
- Dept of Respiratory and Critical Care MedicineThe First Affiliated Hospital of Chongqing Medical UniversityChongqingChina
| | - Hairong Lian
- Department of Respiratory MedicineAffiliated Hospital of Jiangnan UniversityWuxiChina
| | - Jiangrong Liao
- Department of Respiratory MedicineGuizhou Aerospace HospitalZunyiChina
| | - Dan Liu
- Department of Respiratory and Critical Care MedicineWest China Hospital of Sichuan UniversityChengduChina
| | - Zhuang Luo
- Department of Respiratory and Critical Care MedicineFirst Affiliated Hospital of Kunming Medical UniversityKunmingChina
| | - Haifeng Ouyang
- Department of Respiratory DiseasesXi'an International Medical CenterXi'anChina
| | - Yongchun Shen
- Department of Respiratory and Critical Care MedicineWest China Hospital of Sichuan UniversityChengduChina
| | - Yiwei Shi
- Department of Respiratory and Critical Care MedicineShanxi Medical University Affiliated First HospitalTaiyuanChina
| | - Chunli Tang
- China State Key Laboratory of Respiratory Disease & National Clinical Research Center for Respiratory DiseaseThe First Affiliated Hospital of Guangzhou Medical UniversityGuangzhouChina
| | - Nansheng Wan
- Department of Respiratory and Critical Care MedicineTianjin Medical University General HospitalTianjinChina
| | - Tao Wang
- Department of Respiratory and Critical Care Medicine, Tongji Hospital, Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina
| | - Hong Wang
- Department of Respiratory MedicineLanzhou University Second HospitalLanzhouChina
| | - Huaqi Wang
- Department of Respiratory MedicineThe First Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
| | - Juan Wang
- Department of Respiratory and Critical Care Medicine, Beijing Tiantan HospitalCapital Medical UniversityBeijingChina
| | - Xuemei Wu
- Department of Respiratory CentreThe Second Affiliated Hospital of Xiamen Medical CollegeXiamenChina
| | - Yang Xia
- Department of Respiratory and Critical Care MedicineSecond Affiliated Hospital of Zhejiang University School of MedicineHangzhouChina
| | - Kui Xiao
- Department of Respiratory Medicine, The Second Xiangya HospitalCentral South UniversityChangshaChina
| | - Wujian Xu
- Department of Respiratory and Critical Care Medicine, Shanghai East HospitalTongji University School of MedicineShanghaiChina
| | - Fei Xu
- Department of Respiratory and Critical Care MedicineThe First Affiliated Hospital of Nanchang UniversityNanchangChina
| | - Huizhen Yang
- Department of Respiratory and Critical Care Medicine, Henan Provincial People's Hospital, People's Hospital of Zhengzhou UniversityZhengzhouChina
| | - Junyong Yang
- Department of Respiratory MedicineXinjiang Chest HospitalWulumuqiChina
| | - Taosheng Ye
- Department of TuberculosisThe Third People's Hospital of ShenzhenShenzhenChina
| | - Xianwei Ye
- Department of Pulmonary and Critical Care MedicineGuizhou Provincial People's HospitalGuiyangChina
| | - Pengfei Yu
- Department of Respiratory and Critical Care Medicine, Yantai Yuhuangding HospitalAffiliated with the Medical College of QingdaoYantaiChina
| | - Nan Zhang
- Department of Respiratory Medicine, Emergency General HospitalBeijingChina
| | - Peng Zhang
- Pulmonary Intervention DepartmentAnhui Chest HospitalHefeiChina
| | - Quncheng Zhang
- Department of Respiratory and Critical Care Medicine, Henan Provincial People's Hospital, People's Hospital of Zhengzhou UniversityZhengzhouChina
| | - Qi Zhao
- Department of Respiratory Medicine, Nanjing Drum Tower HospitalNanjing University Medical SchoolNanjingChina
| | - Xiaoxuan Zheng
- Department of Respiratory Endoscopy, Shanghai Chest HospitalShanghai Jiao Tong University School of MedicineShanghaiChina
- Department of Respiratory and Critical Care Medicine, Shanghai Chest HospitalShanghai Jiao Tong University School of MedicineShanghaiChina
- Shanghai Engineering Research Center of Respiratory EndoscopyShanghaiChina
| | - Jun Zou
- Department of Respiratory and Critical Care Medicine, Sichuan Provincial People's HospitalUniversity of Electronic Science and Technology of ChinaChengduChina
| | - Enguo Chen
- Department of Pulmonary and Critical Care Medicine, Regional Medical Center for National Institute of Respiratory DiseaseSir Run Run Shaw Hospital of Zhejiang UniversityHangzhouChina
| | - Jiayuan Sun
- Department of Respiratory Endoscopy, Shanghai Chest HospitalShanghai Jiao Tong University School of MedicineShanghaiChina
- Department of Respiratory and Critical Care Medicine, Shanghai Chest HospitalShanghai Jiao Tong University School of MedicineShanghaiChina
- Shanghai Engineering Research Center of Respiratory EndoscopyShanghaiChina
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Ali H, Weinstein J, Sarwar A, Evenson A, Raven K, Curry MP, Ahmed M. Angiography with cone-beam CT versus contrast-enhanced MRI for living donor transplant imaging: Is MRI enough? Clin Anat 2024; 37:185-192. [PMID: 37638802 DOI: 10.1002/ca.24104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2023] [Accepted: 08/03/2023] [Indexed: 08/29/2023]
Abstract
The purpose of this study is to compare the subjective and objective quality and confidence between conventional angiography with cone-beam computed tomography (CBCT) and magnetic resonance imaging (MRI) for the preoperative evaluation of potential donors for living donor liver transplant. Seventeen patients undergoing preoperative donor evaluation for living donor liver transplantation that underwent angiography with CBCT and contrast-enhanced MRI for evaluation of hepatic vascular anatomy were included in the study. Four attending radiologists interpreted anonymized, randomized angiography with CBCT images and MRIs, rating the diagnostic quality and confidence of their interpretation (on a 3-point scale) for each element, as well as clinically relevant measurements. Overall, the readers rated the quality of angiography with CBCT to be higher than that of MRI (median [interquartile range] = 3 (2, 3) vs. 2 (1-3), p < 0.001) across all patients. Readers of angiography with CBCT had more confidence in their interpretations as an average of all elements evaluated than the MRI readers (3 (3) vs. 3 (2, 3), p < 0.001). When the same reader interpreted both MRI and CBCT, the right hepatic artery diameter (3.8 mm ± 0.72 mm vs. 4.5 mm ± 1.2 mm, p < 0.005) and proper hepatic artery diameter (4.43 mm ± 0.98 mm vs. 5.4 mm ± 1.05 mm, p < 0.003) were significantly different between MRI and CBCT. There was poor interrater reliability for determining segment IV arterial supply for both modalities (κ < 0.2). Angiography with CBCT provides higher subjective diagnostic quality and greater radiologist confidence than MRI. The difference in measurements between CBCT and MRI when the same reader reads both studies suggests CBCT adds additional information over MRI evaluation alone.
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Affiliation(s)
- Hamza Ali
- Department of Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Jeffrey Weinstein
- Department of Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Ammar Sarwar
- Department of Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Amy Evenson
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Kristin Raven
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Michael P Curry
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Muneeb Ahmed
- Department of Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
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Yu Y, Gao G, Gao X, Zhang Z, He Y, Shi L, Kang Z. A study on the radiomic correlation between CBCT and pCT scans based on modified 3D-RUnet image segmentation. Front Oncol 2024; 14:1301710. [PMID: 38463234 PMCID: PMC10921553 DOI: 10.3389/fonc.2024.1301710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Accepted: 02/06/2024] [Indexed: 03/12/2024] Open
Abstract
Purpose The present study is based on evidence indicating a potential correlation between cone-beam CT (CBCT) measurements of tumor size, shape, and the stage of locally advanced rectal cancer. To further investigate this relationship, the study quantitatively assesses the correlation between positioning CT (pCT) and CBCT in the radiomics features of these cancers, and examines their potential for substitution. Methods In this study, 103 patients diagnosed with locally advanced rectal cancer and undergoing neoadjuvant chemoradiotherapy were selected as participants. Their CBCT and pCT images were used to divide the participants into two groups: a training set and a validation set, with a 7:3 ratio. An improved conventional 3D-RUNet (CLA-UNet) deep learning model was trained on the training set data and then applied to the validation set. The DSC, HD95 and ASSD were calculated for quantitative evaluation purposes. Then, radiomics features were extracted from 30 patients of the test set. Results The experiments demonstrate that, the modified model achieves an average DSC score 0.792 for pCT and 0.672 for CBCT scans. 1037 features were extracted from each patient's CBCT and pCT images, 73 image features were found to have R values greater than 0.9, including three features related to the staging and prognosis of rectal cancer. Conclusion In this study, we proposed an automatic, fast, and consistent method for rectal cancer GTV segmentation for pCT and CBCT scans. The findings of radiomic results indicate that CBCT images have significant research value in the field of radiomics.
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Affiliation(s)
- Yanjuan Yu
- College of Electronic Engineering, Zhangzhou Institute of Technology, Zhangzhou, Fujian, China
| | - Guanglu Gao
- Department of Radiation Oncology, the First Affiliated Hospital of Xiamen University, Xiamen, Fujian, China
| | - Xiang Gao
- Department of Radiation Oncology, the First Affiliated Hospital of Xiamen University, Xiamen, Fujian, China
| | - Zongkai Zhang
- Department of Radiation Oncology, the First Affiliated Hospital of Xiamen University, Xiamen, Fujian, China
| | - Yipeng He
- Department of Radiation Oncology, the First Affiliated Hospital of Xiamen University, Xiamen, Fujian, China
| | - Liwan Shi
- Department of Radiation Oncology, the First Affiliated Hospital of Xiamen University, Xiamen, Fujian, China
| | - Zheng Kang
- Department of Radiation Oncology, the First Affiliated Hospital of Xiamen University, Xiamen, Fujian, China
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Tu TH, Kuo YH, Chang CC, Kuo CH, Chang HK, Fay LY, Yeh MY, Ko CC, Huang WC, Wu JC. Comparison of intraoperative cone-beam CT versus preoperative fan-beam CT for navigated spine surgery: a prospective randomized study. J Neurosurg Spine 2024; 40:240-247. [PMID: 38000063 DOI: 10.3171/2023.9.spine23422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2023] [Accepted: 09/18/2023] [Indexed: 11/26/2023]
Abstract
OBJECTIVE This prospective randomized study aimed to investigate the accuracy, radiation exposure, and surgical workflow optimization of a novel intraoperative spinal navigation system using preoperative fan-beam (FB) CT versus the classic intraoperative cone-beam (CB) CT in patients undergoing minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF). METHODS In this two-arm, single-center, randomized study, the authors evaluated the safety and clinical outcomes of a novel navigation system for pedicle screw placement in spine surgery. RESULTS The accuracy of pedicle screw placement in the experimental group (FB group) was 94.38%, while it was 94.55% in the control group (CB group). Notably, the intraoperative radiation exposure to patients in the FB CT group (mean 0.361 ± 0.261 mSv) was significantly lower than that in the CB CT group (mean 6.526 ± 13.591 mSv) (p < 0.0001). Furthermore, the intraoperative preparation time for screw placement in the FB group (mean 10.6 ± 5.62 minutes) was significantly lower than that in the CB group (mean 17.6 ± 5.59 minutes) (p = 0.0004). No significant differences were observed for blood loss during surgery, total radiation exposure to surgeons, mean time for inserting a single pedicle screw, revision surgery rate, patients' reported outcomes, and length of postoperative hospital stay between the two groups. Significant differences were observed for intraoperative radiation exposure to patients and the preparation time for pedicle screw placement. CONCLUSIONS The preoperative FB CT-based intraoperative spinal navigation system demonstrated comparable accuracy and safety when compared with the intraoperative CB CT-based system. Moreover, the FB CT-based system had a shorter time for screw placement and reduced intraoperative radiation exposure to patients. These findings support the potential benefits of adopting this novel navigation system to enhance surgical precision and reduce radiation-related risks in MIS-TLIF procedures.
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Affiliation(s)
- Tsung-Hsi Tu
- 1Department of Neurosurgery, Neurological Institute, Taipei Veterans General Hospital, Taipei
- 2School of Medicine, National Yang Ming Chiao Tung University, Taipei
| | - Yi-Hsuan Kuo
- 1Department of Neurosurgery, Neurological Institute, Taipei Veterans General Hospital, Taipei
- 3Institute of Biomedical Informatics, National Yang Ming Chiao Tung University, Taipei
| | - Chih-Chang Chang
- 1Department of Neurosurgery, Neurological Institute, Taipei Veterans General Hospital, Taipei
- 2School of Medicine, National Yang Ming Chiao Tung University, Taipei
- 4Department of Biomedical Engineering, School of Biomedical Science and Engineering, National Yang Ming Chiao Tung University, Taipei
| | - Chao-Hung Kuo
- 1Department of Neurosurgery, Neurological Institute, Taipei Veterans General Hospital, Taipei
- 2School of Medicine, National Yang Ming Chiao Tung University, Taipei
- 4Department of Biomedical Engineering, School of Biomedical Science and Engineering, National Yang Ming Chiao Tung University, Taipei
| | - Hsuan-Kan Chang
- 1Department of Neurosurgery, Neurological Institute, Taipei Veterans General Hospital, Taipei
- 2School of Medicine, National Yang Ming Chiao Tung University, Taipei
- 5Department of Biomedical Imaging and Radiological Sciences, National Yang Ming Chiao Tung University, Taipei; and
| | - Li-Yu Fay
- 1Department of Neurosurgery, Neurological Institute, Taipei Veterans General Hospital, Taipei
- 2School of Medicine, National Yang Ming Chiao Tung University, Taipei
| | - Mei-Yin Yeh
- 1Department of Neurosurgery, Neurological Institute, Taipei Veterans General Hospital, Taipei
- 2School of Medicine, National Yang Ming Chiao Tung University, Taipei
- 6Institute of Pharmacology, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Chin-Chu Ko
- 1Department of Neurosurgery, Neurological Institute, Taipei Veterans General Hospital, Taipei
- 2School of Medicine, National Yang Ming Chiao Tung University, Taipei
| | - Wen-Cheng Huang
- 1Department of Neurosurgery, Neurological Institute, Taipei Veterans General Hospital, Taipei
- 2School of Medicine, National Yang Ming Chiao Tung University, Taipei
| | - Jau-Ching Wu
- 1Department of Neurosurgery, Neurological Institute, Taipei Veterans General Hospital, Taipei
- 2School of Medicine, National Yang Ming Chiao Tung University, Taipei
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Østergaard DE, Bryce-Atkinson A, Skaarup M, Smulders B, Davies LSC, Whitfield G, Janssens GO, Hjalgrim LL, Richter IV, van Herk M, Aznar M, Vestmø Maraldo M. Paediatric CBCT protocols for image-guided radiotherapy; outcome of a survey across SIOP Europe affiliated countries and literature review. Radiother Oncol 2024; 190:109963. [PMID: 38406888 DOI: 10.1016/j.radonc.2023.109963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 10/17/2023] [Accepted: 10/20/2023] [Indexed: 02/27/2024]
Abstract
BACKGROUND Implementation of daily cone-beam CT (CBCT) into clinical practice in paediatric image-guided radiotherapy (IGRT) lags behind compared to adults. Surveys report wide variation in practice for paediatric IGRT and technical information remains unreported. In this study we report on technical settings from applied paediatric CBCT protocols and review the literature for paediatric CBCT protocols. METHODS From September to October 2022, a survey was conducted among 246 SIOPE-affiliated centres across 35 countries. The survey consisted of 3 parts: 1) baseline information; technical CBCT exposure settings and patient set-up procedure for 2) brain/head, and 3) abdomen. Descriptive statistics was used to summarise current practice. The literature was reviewed systematically with two reviewers obtaining consensus RESULTS: The literature search revealed 22 papers concerning paediatric CBCT protocols. Seven papers focused on dose-optimisation. Responses from 50/246 centres in 25/35 countries were collected: 44/50 treated with photons and 10/50 with protons. In total, 48 brain/head and 53 abdominal protocols were reported. 42/50 centres used kV-CBCT for brain/head and 35/50 for abdomen; daily CBCT was used for brain/head = 28/48 (58%) and abdomen = 33/53 62%. Greater consistency was seen in brain/head protocols (dose range 0.32 - 67.7 mGy) compared to abdominal (dose range 0.27 - 119.7 mGy). CONCLUSION Although daily CBCT is now widely used in paediatric IGRT, our survey demonstrates a wide range of technical settings, suggesting an unmet need to optimise paediatric IGRT protocols. This is in accordance with the literature. However, there are only few paediatric optimisation studies suggesting that dose reduction is possible while maintaining image quality.
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Affiliation(s)
- Daniella Elisabet Østergaard
- Section of Radiotherapy, Department of Oncology, Centre for Cancer and Organ Diseases, Copenhagen University Hospital, Copenhagen, Denmark; Faculty of Health and Medical Sciences, Copenhagen University, Copenhagen, Denmark.
| | - Abigail Bryce-Atkinson
- Division of Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK
| | - Mikkel Skaarup
- Section of Radiotherapy, Department of Oncology, Centre for Cancer and Organ Diseases, Copenhagen University Hospital, Copenhagen, Denmark
| | - Bob Smulders
- Section of Radiotherapy, Department of Oncology, Centre for Cancer and Organ Diseases, Copenhagen University Hospital, Copenhagen, Denmark; Danish Centre for Particle Therapy, Aarhus University Hospital, Aarhus, Denmark
| | | | - Gillian Whitfield
- Manchester Academic Health Science Centre, The Christie NHS Foundation Trust, Manchester, UK; The Children's Brain Tumour Research Network, The University of Manchester, Royal Manchester Children's Hospital, Manchester, UK
| | - Geert O Janssens
- Department of Radiation Oncology, University Medical Center Utrecht, Utrecht, the Netherlands; Princess Máxima Center for Pediatric Oncology, Utrecht, the Netherlands
| | - Lisa Lyngsie Hjalgrim
- Department of Paediatrics and Adolescent Medicine, Copenhagen University Hospital, Copenhagen, Denmark
| | - Ivan Vogelius Richter
- Section of Radiotherapy, Department of Oncology, Centre for Cancer and Organ Diseases, Copenhagen University Hospital, Copenhagen, Denmark; Faculty of Health and Medical Sciences, Copenhagen University, Copenhagen, Denmark
| | - Marcel van Herk
- Division of Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK
| | - Marianne Aznar
- Division of Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK
| | - Maja Vestmø Maraldo
- Section of Radiotherapy, Department of Oncology, Centre for Cancer and Organ Diseases, Copenhagen University Hospital, Copenhagen, Denmark
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Zhang C, He W, Liu L, Dai J, Salim Ahmad I, Xie Y, Liang X. Volumetric feature points integration with bio-structure-informed guidance for deformable multi-modal CT image registration. Phys Med Biol 2023; 68:245007. [PMID: 37844603 DOI: 10.1088/1361-6560/ad03d2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Accepted: 10/16/2023] [Indexed: 10/18/2023]
Abstract
Objective.Medical image registration represents a fundamental challenge in medical image processing. Specifically, CT-CBCT registration has significant implications in the context of image-guided radiation therapy (IGRT). However, traditional iterative methods often require considerable computational time. Deep learning based methods, especially when dealing with low contrast organs, are frequently entangled in local optimal solutions.Approach.To address these limitations, we introduce a registration method based on volumetric feature points integration with bio-structure-informed guidance. Surface point cloud is generated from segmentation labels during the training stage, with both the surface-registered point pairs and voxel feature point pairs co-guiding the training process, thereby achieving higher registration accuracy.Main results.Our findings have been validated on paired CT-CBCT datasets. In comparison with other deep learning registration methods, our approach has improved the precision by 6%, reaching a state-of-the-art status.Significance.The integration of voxel feature points and bio-structure feature points to guide the training of the medical image registration network has achieved promising results. This provides a meaningful direction for further research in medical image registration and IGRT.
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Affiliation(s)
- Chulong Zhang
- Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055 Guangdong, People's Republic of China
| | - Wenfeng He
- Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055 Guangdong, People's Republic of China
| | - Lin Liu
- Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055 Guangdong, People's Republic of China
| | - Jingjing Dai
- Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055 Guangdong, People's Republic of China
| | - Isah Salim Ahmad
- Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055 Guangdong, People's Republic of China
| | - Yaoqin Xie
- Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055 Guangdong, People's Republic of China
| | - Xiaokun Liang
- Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055 Guangdong, People's Republic of China
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Yun S, Jeong U, Lee D, Kim H, Cho S. Image quality improvement in bowtie-filter-equipped cone-beam CT using a dual-domain neural network. Med Phys 2023; 50:7498-7512. [PMID: 37669510 DOI: 10.1002/mp.16693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 08/08/2023] [Accepted: 08/09/2023] [Indexed: 09/07/2023] Open
Abstract
BACKGROUND The bowtie-filter in cone-beam CT (CBCT) causes spatially nonuniform x-ray beam often leading to eclipse artifacts in the reconstructed image. The artifacts are further confounded by the patient scatter, which is therefore patient-dependent as well as system-specific. PURPOSE In this study, we propose a dual-domain network for reducing the bowtie-filter-induced artifacts in CBCT images. METHODS In the projection domain, the network compensates for the filter-induced beam-hardening that are highly related to the eclipse artifacts. The output of the projection-domain network was used for image reconstruction and the reconstructed images were fed into the image-domain network. In the image domain, the network further reduces the remaining cupping artifacts that are associated with the scatter. A single image-domain-only network was also implemented for comparison. RESULTS The proposed approach successfully enhanced soft-tissue contrast with much-reduced image artifacts. In the numerical study, the proposed method decreased perceptual loss and root-mean-square-error (RMSE) of the images by 84.5% and 84.9%, respectively, and increased the structure similarity index measure (SSIM) by 0.26 compared to the original input images on average. In the experimental study, the proposed method decreased perceptual loss and RMSE of the images by 87.2% and 92.1%, respectively, and increased SSIM by 0.58 compared to the original input images on average. CONCLUSIONS We have proposed a deep-learning-based dual-domain framework to reduce the bowtie-filter artifacts and to increase the soft-tissue contrast in CBCT images. The performance of the proposed method has been successfully demonstrated in both numerical and experimental studies.
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Affiliation(s)
- Sungho Yun
- Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, South Korea
| | - Uijin Jeong
- Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, South Korea
| | - Donghyeon Lee
- Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, South Korea
| | - Hyeongseok Kim
- KAIST Institute for Artificial Intelligence, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, South Korea
| | - Seungryong Cho
- Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, South Korea
- KAIST Institute for Artificial Intelligence, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, South Korea
- KAIST Institute for Health Science and Technology, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, South Korea
- KAIST Institute for IT Convergence, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, South Korea
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Becksfort J, Uh J, Saunders A, Byrd JA, Worrall HM, Marker M, Melendez-Suchi C, Li Y, Chang J, Raghavan K, Merchant TE, Hua CH. Setup Uncertainty of Pediatric Brain Tumor Patients Receiving Proton Therapy: A Prospective Study. Cancers (Basel) 2023; 15:5486. [PMID: 38001746 PMCID: PMC10670653 DOI: 10.3390/cancers15225486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2023] [Revised: 11/11/2023] [Accepted: 11/13/2023] [Indexed: 11/26/2023] Open
Abstract
This study quantifies setup uncertainty in brain tumor patients who received image-guided proton therapy. Patients analyzed include 165 children, adolescents, and young adults (median age at radiotherapy: 9 years (range: 10 months to 24 years); 80 anesthetized and 85 awake) enrolled in a single-institution prospective study from 2020 to 2023. Cone-beam computed tomography (CBCT) was performed daily to calculate and correct manual setup errors, once per course after setup correction to measure residual errors, and weekly after treatments to assess intrafractional motion. Orthogonal radiographs were acquired consecutively with CBCT for paired comparisons of 40 patients. Translational and rotational errors were converted from 6 degrees of freedom to a scalar by a statistical approach that considers the distance from the target to the isocenter. The 95th percentile of setup uncertainty was reduced by daily CBCT from 10 mm (manual positioning) to 1-1.5 mm (after correction) and increased to 2 mm by the end of fractional treatment. A larger variation existed between the roll corrections reported by radiographs vs. CBCT than for pitch and yaw, while there was no statistically significant difference in translational variation. A quantile mixed regression model showed that the 95th percentile of intrafractional motion was 0.40 mm lower for anesthetized patients (p=0.0016). Considering additional uncertainty in radiation-imaging isocentricity, the commonly used total plan robustness of 3 mm against positional uncertainty would be appropriate for our study cohort.
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Affiliation(s)
- Jared Becksfort
- Department of Radiation Oncology, St. Jude Children’s Research Hospital, Memphis, TN 38105, USA; (J.U.); (J.A.B.); (H.M.W.); (T.E.M.); (C.-h.H.)
| | - Jinsoo Uh
- Department of Radiation Oncology, St. Jude Children’s Research Hospital, Memphis, TN 38105, USA; (J.U.); (J.A.B.); (H.M.W.); (T.E.M.); (C.-h.H.)
| | - Andrew Saunders
- Department of Radiation Oncology, St. Jude Children’s Research Hospital, Memphis, TN 38105, USA; (J.U.); (J.A.B.); (H.M.W.); (T.E.M.); (C.-h.H.)
| | - Julia A. Byrd
- Department of Radiation Oncology, St. Jude Children’s Research Hospital, Memphis, TN 38105, USA; (J.U.); (J.A.B.); (H.M.W.); (T.E.M.); (C.-h.H.)
| | - Hannah M. Worrall
- Department of Radiation Oncology, St. Jude Children’s Research Hospital, Memphis, TN 38105, USA; (J.U.); (J.A.B.); (H.M.W.); (T.E.M.); (C.-h.H.)
| | - Matt Marker
- Department of Radiation Oncology, St. Jude Children’s Research Hospital, Memphis, TN 38105, USA; (J.U.); (J.A.B.); (H.M.W.); (T.E.M.); (C.-h.H.)
| | - Christian Melendez-Suchi
- Department of Radiation Oncology, St. Jude Children’s Research Hospital, Memphis, TN 38105, USA; (J.U.); (J.A.B.); (H.M.W.); (T.E.M.); (C.-h.H.)
| | - Yimei Li
- Department of Biostatistics, St. Jude Children’s Research Hospital, Memphis, TN 38105, USA
| | - Jenghwa Chang
- Department of Radiation Medicine, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY 11549, USA
| | - Kavitha Raghavan
- Department of Pediatric Medicine, St. Jude Children’s Research Hospital, Memphis, TN 38105, USA;
| | - Thomas E. Merchant
- Department of Radiation Oncology, St. Jude Children’s Research Hospital, Memphis, TN 38105, USA; (J.U.); (J.A.B.); (H.M.W.); (T.E.M.); (C.-h.H.)
| | - Chia-ho Hua
- Department of Radiation Oncology, St. Jude Children’s Research Hospital, Memphis, TN 38105, USA; (J.U.); (J.A.B.); (H.M.W.); (T.E.M.); (C.-h.H.)
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Lyu T, Wu Z, Ma G, Jiang C, Zhong X, Xi Y, Chen Y, Zhu W. PDS-MAR: a fine-grained projection-domain segmentation-based metal artifact reduction method for intraoperative CBCT images with guidewires. Phys Med Biol 2023; 68:215007. [PMID: 37802062 DOI: 10.1088/1361-6560/ad00fc] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Accepted: 10/06/2023] [Indexed: 10/08/2023]
Abstract
Objective.Since the invention of modern Computed Tomography (CT) systems, metal artifacts have been a persistent problem. Due to increased scattering, amplified noise, and limited-angle projection data collection, it is more difficult to suppress metal artifacts in cone-beam CT, limiting its use in human- and robot-assisted spine surgeries where metallic guidewires and screws are commonly used.Approach.To solve this problem, we present a fine-grained projection-domain segmentation-based metal artifact reduction (MAR) method termed PDS-MAR, in which metal traces are augmented and segmented in the projection domain before being inpainted using triangular interpolation. In addition, a metal reconstruction phase is proposed to restore metal areas in the image domain.Main results.The proposed method is tested on both digital phantom data and real scanned cone-beam computed tomography (CBCT) data. It achieves much-improved quantitative results in both metal segmentation and artifact reduction in our phantom study. The results on real scanned data also show the superiority of this method.Significance.The concept of projection-domain metal segmentation would advance MAR techniques in CBCT and has the potential to push forward the use of intraoperative CBCT in human-handed and robotic-assisted minimal invasive spine surgeries.
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Affiliation(s)
- Tianling Lyu
- Research Center for Augmented Intelligence, Zhejiang Lab, Hangzhou, People's Republic of China
| | - Zhan Wu
- Laboratory of Imaging Science and Technology, Southeast University, Nanjing, People's Republic of China
| | - Gege Ma
- Research Center for Augmented Intelligence, Zhejiang Lab, Hangzhou, People's Republic of China
| | - Chen Jiang
- Research Center for Augmented Intelligence, Zhejiang Lab, Hangzhou, People's Republic of China
| | - Xinyun Zhong
- Laboratory of Imaging Science and Technology, Southeast University, Nanjing, People's Republic of China
| | - Yan Xi
- First-Imaging Tech., Shanghai, People's Republic of China
| | - Yang Chen
- Laboratory of Imaging Science and Technology, Southeast University, Nanjing, People's Republic of China
- Jiangsu Provincial Joint International Research Laboratory of Medical Information Processing, Southeast University, Nanjing, People's Republic of China
| | - Wentao Zhu
- Research Center for Augmented Intelligence, Zhejiang Lab, Hangzhou, People's Republic of China
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Choi K, Kim SH, Kim S. Self-supervised denoising of projection data for low-dose cone-beam CT. Med Phys 2023; 50:6319-6333. [PMID: 37079443 DOI: 10.1002/mp.16421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 04/03/2023] [Accepted: 04/03/2023] [Indexed: 04/21/2023] Open
Abstract
BACKGROUND Convolutional neural networks (CNNs) have shown promising results in image denoising tasks. While most existing CNN-based methods depend on supervised learning by directly mapping noisy inputs to clean targets, high-quality references are often unavailable for interventional radiology such as cone-beam computed tomography (CBCT). PURPOSE In this paper, we propose a novel self-supervised learning method that reduces noise in projections acquired by ordinary CBCT scans. METHODS With a network that partially blinds input, we are able to train the denoising model by mapping the partially blinded projections to the original projections. Additionally, we incorporate noise-to-noise learning into the self-supervised learning by mapping the adjacent projections to the original projections. With standard image reconstruction methods such as FDK-type algorithms, we can reconstruct high-quality CBCT images from the projections denoised by our projection-domain denoising method. RESULTS In the head phantom study, we measure peak signal-to-noise ratio (PSNR) and structural similarity index measure (SSIM) values of the proposed method along with the other denoising methods and uncorrected low-dose CBCT data for a quantitative comparison both in projection and image domains. The PSNR and SSIM values of our self-supervised denoising approach are 27.08 and 0.839, whereas those of uncorrected CBCT images are 15.68 and 0.103, respectively. In the retrospective study, we assess the quality of interventional patient CBCT images to evaluate the projection-domain and image-domain denoising methods. Both qualitative and quantitative results indicate that our approach can effectively produce high-quality CBCT images with low-dose projections in the absence of duplicate clean or noisy references. CONCLUSIONS Our self-supervised learning strategy is capable of restoring anatomical information while efficiently removing noise in CBCT projection data.
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Affiliation(s)
- Kihwan Choi
- Bionics Research Center, Korea Institute of Science and Technology, Seoul, Republic of Korea
| | - Seung Hyoung Kim
- Department of Radiology, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Sungwon Kim
- Department of Radiology, Yonsei University College of Medicine, Seoul, Republic of Korea
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Baumgart L, Ille S, Kirschke JS, Meyer B, Krieg SM. Radiation doses and accuracy of navigated pedicle screw placement in cervical and thoracic spine surgery: a comparison of sliding gantry CT and mobile cone-beam CT in a homogeneous cohort. J Neurosurg Spine 2023; 39:363-369. [PMID: 37310023 DOI: 10.3171/2023.4.spine23174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Accepted: 04/21/2023] [Indexed: 06/14/2023]
Abstract
OBJECTIVE Multiple solutions for navigation-guided pedicle screw placement are currently available. Intraoperative imaging techniques are invaluable for spinal surgery, but often there is little attention paid to patient radiation exposure. This study aimed to compare the applied radiation doses of sliding gantry CT (SGCT)- and mobile cone-beam CT (CBCT)-based pedicle screw placement for spinal instrumentation. METHODS The authors retrospectively analyzed 183 and 54 patients who underwent SGCT- or standard CBCT-based pedicle screw placement, respectively, for spinal instrumentation at their department between June 2019 and January 2020. SGCT uses an automated radiation dose adjustment. RESULTS Baseline characteristics, including the number of screws per patient and the number of instrumented levels, did not significantly differ between the two groups. Although the accuracy of screw placement according to Gertzbein-Robbins classification did not differ between the two groups, more screws had to be revised intraoperatively in the CBCT group (SGCT 2.7% vs CBCT 6.0%, p = 0.0036). Mean (± SD) radiation doses for the first (SGCT 484.0 ± 201.1 vs CBCT 687.4 ± 188.5 mGy*cm, p < 0.0001), second (SGCT 515.8 ± 216.3 vs CBCT 658.3 ± 220.1 mGy*cm, p < 0.0001), third (SGCT 531.3 ± 237.5 vs CBCT 641.6 ± 177.3 mGy*cm, p = 0.0140), and total (SGCT 1216.9 ± 699.3 vs CBCT 2000.3 ± 921.0 mGy*cm, p < 0.0001) scans were significantly lower for SGCT. This was also true for radiation doses per scanned level (SGCT 461.9 ± 429.3 vs CBCT 1004.1 ± 905.1 mGy*cm, p < 0.0001) and radiation doses per screw (SGCT 172.6 ± 110.1 vs CBCT 349.6 ± 273.4 mGy*cm, p < 0.0001). CONCLUSIONS The applied radiation doses were significantly lower using SGCT for navigated pedicle screw placement in spinal instrumentation. A modern CT scanner on a sliding gantry leads to lower radiation doses, especially through automated 3D radiation dose adjustment.
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Affiliation(s)
| | - Sebastian Ille
- Departments of1Neurosurgery and
- 2TUM Neuroimaging Center, Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Munich, Germany
| | | | | | - Sandro M Krieg
- Departments of1Neurosurgery and
- 2TUM Neuroimaging Center, Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Munich, Germany
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Abstract
Assessment of carpal alignment traditionally uses carpal bone axes measured on lateral radiographs. In this study, three-dimensional axes were defined for carpal bones using segmentation and numerical modelling of CT data of 121 neutrally positioned, asymptomatic wrists. The geometric axis was used for radius, scaphoid and capitate, whereas the axis based on a line perpendicular to the articular surface was used for the other carpal bones. Normal values of radiocarpal angles in the radial coordinate and the reliability of the computer-aided analysis are reported. The mean sagittal radiocarpal angles (positive in palmar direction) were as follows: scaphoid 58° (SD 10°), lunate 0° (SD 11°), triquetrum 12° (SD 8°), trapezium 17° (SD 8°), trapezoid -10° (SD 7°), capitate -17° (SD 9°) and hamate 2° (SD 7°). The mean coronal radiocarpal angles (positive in ulnar direction) were -42° (SD 9°), -20° (SD 4°), -49° (SD 4°), -32° (SD 6°), -16° (SD 5°), 2° (SD 7°) and 8° (SD 6°), respectively. The intra-observer reliability of the measurements was excellent (mean intraclass correlations coefficient 0.98). This study provides guidelines on how to measure and quantify carpal alignment three-dimensionally, and a database for the normal values. Together, these may be useful when analysing various wrist pathologies and kinematics of the wrist.
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Affiliation(s)
- Theresa E K Höglund
- Department of Hand Surgery, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Robert M J Sippo
- Department of Hand Surgery, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Eero Waris
- Department of Hand Surgery, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
- Mehiläinen Helsinki Hospital, Helsinki, Finland
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Reiners K, Dagan R, Holtzman A, Bryant C, Andersson S, Nilsson R, Hong L, Johnson P, Zhang Y. CBCT-Based Dose Monitoring and Adaptive Planning Triggers in Head and Neck PBS Proton Therapy. Cancers (Basel) 2023; 15:3881. [PMID: 37568697 PMCID: PMC10417147 DOI: 10.3390/cancers15153881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 07/26/2023] [Accepted: 07/27/2023] [Indexed: 08/13/2023] Open
Abstract
PURPOSE To investigate the feasibility of using cone-beam computed tomography (CBCT)-derived synthetic CTs to monitor the daily dose and trigger a plan review for adaptive proton therapy (APT) in head and neck cancer (HNC) patients. METHODS For 84 HNC patients treated with proton pencil-beam scanning (PBS), same-day CBCT and verification CT (vfCT) pairs were retrospectively collected. The ground truth CT (gtCT) was created by deforming the vfCT to the same-day CBCT, and it was then used as a dosimetric baseline and for establishing plan review trigger recommendations. Two different synthetic CT algorithms were tested; the corrected CBCT (corrCBCT) was created using an iterative image correction method and the virtual CT (virtCT) was created by deforming the planning CT to the CBCT, followed by a low-density masking process. Clinical treatment plans were recalculated on the image sets for evaluation. RESULTS Plan review trigger criteria for adaptive therapy were established after closely reviewing the cohort data. Compared to the vfCT, the corrCBCT and virtCT reliably produced dosimetric data more similar to the gtCT. The average discrepancy in D99 for high-risk clinical target volumes (CTV) was 1.1%, 0.7%, and 0.4% and for standard-risk CTVs was 1.8%, 0.5%, and 0.5% for the vfCT, corrCBCT, and virtCT, respectively. CONCLUSION Streamlined APT has been achieved with the proposed plan review criteria and CBCT-based synthetic CT workflow.
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Affiliation(s)
- Keaton Reiners
- University of Florida Health Proton Therapy Institute, Jacksonville, FL 32206, USA; (K.R.); (R.D.); (C.B.); (P.J.)
- Medical Physics Graduate Program, University of Florida College of Medicine, Gainesville, FL 32610, USA
| | - Roi Dagan
- University of Florida Health Proton Therapy Institute, Jacksonville, FL 32206, USA; (K.R.); (R.D.); (C.B.); (P.J.)
- Department of Radiation Oncology, University of Florida College of Medicine, Gainesville, FL 32610, USA
| | - Adam Holtzman
- Department of Radiation Oncology, Mayo Clinic, Jacksonville, FL 32224, USA;
| | - Curtis Bryant
- University of Florida Health Proton Therapy Institute, Jacksonville, FL 32206, USA; (K.R.); (R.D.); (C.B.); (P.J.)
- Department of Radiation Oncology, University of Florida College of Medicine, Gainesville, FL 32610, USA
| | | | - Rasmus Nilsson
- RaySearch Laboratories, SE-103 65 Stockholm, Sweden; (S.A.); (R.N.)
| | - Liu Hong
- Ion Beam Applications S.A., 1348 Louvain-la-Neuve, Belgium;
| | - Perry Johnson
- University of Florida Health Proton Therapy Institute, Jacksonville, FL 32206, USA; (K.R.); (R.D.); (C.B.); (P.J.)
- Department of Radiation Oncology, University of Florida College of Medicine, Gainesville, FL 32610, USA
| | - Yawei Zhang
- University of Florida Health Proton Therapy Institute, Jacksonville, FL 32206, USA; (K.R.); (R.D.); (C.B.); (P.J.)
- Department of Radiation Oncology, University of Florida College of Medicine, Gainesville, FL 32610, USA
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Fleiner JC, Woelber JP, Kürschner AC, Lux HC, Schulze D, Hannig C. Software-supported periodontal diagnostics with three-dimensional cone-beam computed tomography compared to conventional two-dimensional panoramic imaging and clinical diagnostics (a prospective study). Int J Comput Dent 2023; 0:0. [PMID: 37341386 DOI: 10.3290/j.ijcd.b4170267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 06/22/2023]
Abstract
AIM Aim of this study comprised the software-supported evaluation of measurement accuracy between cone-beam computed tomography (CBCT) and panoramic radiographs in the assessment of the periodontal bone level in patients with periodontitis and comparison with clinical periodontal parameters. MATERIAL AND METHODS Twenty patients with severe periodontitis (stage III-IV) were evaluated clinically and radiographically (panoramic and CBCT). Diagnostic interpretation comprised three blinded investigators with different levels of experience. Specific software-basing measurement procedure evaluated radiological distances for the mesial, central, and distal bone levels on the oral and vestibular sides of the teeth investigated and furcation upper and lower boundary. Jaw localization, anatomical region-of-interest, the number of roots and experience of the observers were evaluated. All measurements were carried out twice by the same observers within a 6-week interval. RESULTS Slightly higher measurement deviations (SD) in the range of 0.47 (0.40) mm were found for CBCT evaluation compared to panoramic imaging. Pearson correlation analysis showed statistically strong positive correlation for the mesial and distal aspects, moderate positive correlation was found for the investigated furcations between both radiographic modalities. Compared to the clinical reference, the mean total error of measurement (SD) was larger for panoramic imaging (0.66 (0.48) mm) than CBCT (0.27 (0.08) mm) for all three observers. CONCLUSIONS Software-supported CBCT analysis delivers better diagnostic information about the bony periodontal conditions of the patient compared to two-dimensional radiographs. However, it remains unclear if these additional information lead to better periodontal outcomes.
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Lalonde A, Bobić M, Sharp GC, Chamseddine I, Winey B, Paganetti H. Evaluating the effect of setup uncertainty reduction and adaptation to geometric changes on normal tissue complication probability using online adaptive head and neck intensity modulated proton therapy. Phys Med Biol 2023; 68:115018. [PMID: 37164020 PMCID: PMC10351361 DOI: 10.1088/1361-6560/acd433] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2023] [Revised: 05/03/2023] [Accepted: 05/10/2023] [Indexed: 05/12/2023]
Abstract
Objective. To evaluate the impact of setup uncertainty reduction (SUR) and adaptation to geometrical changes (AGC) on normal tissue complication probability (NTCP) when using online adaptive head and neck intensity modulated proton therapy (IMPT).Approach.A cohort of ten retrospective head and neck cancer patients with daily scatter corrected cone-beam CT (CBCT) was studied. For each patient, two IMPT treatment plans were created: one with a 3 mm setup uncertainty robustness setting and one with no explicit setup robustness. Both plans were recalculated on the daily CBCT considering three scenarios: the robust plan without adaptation, the non-robust plan without adaptation and the non-robust plan with daily online adaptation. Online-adaptation was simulated using an in-house developed workflow based on GPU-accelerated Monte Carlo dose calculation and partial spot-intensity re-optimization. Dose distributions associated with each scenario were accumulated on the planning CT, where NTCP models for six toxicities were applied. NTCP values from each scenario were intercompared to quantify the reduction in toxicity risk induced by SUR alone, AGC alone and SUR and AGC combined. Finally, a decision tree was implemented to assess the clinical significance of the toxicity reduction associated with each mechanism.Main results. For most patients, clinically meaningful NTCP reductions were only achieved when SUR and AGC were performed together. In these conditions, total reductions in NTCP of up to 30.48 pp were obtained, with noticeable NTCP reductions for aspiration, dysphagia and xerostomia (mean reductions of 8.25, 5.42 and 5.12 pp respectively). While SUR had a generally larger impact than AGC on NTCP reductions, SUR alone did not induce clinically meaningful toxicity reductions in any patient, compared to only one for AGC alone.SignificanceOnline adaptive head and neck proton therapy can only yield clinically significant reductions in the risk of long-term side effects when combining the benefits of SUR and AGC.
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Affiliation(s)
- Arthur Lalonde
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Mislav Bobić
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
- ETH Zürich, Zürich, Switzerland
| | - Gregory C Sharp
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Ibrahim Chamseddine
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Brian Winey
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Harald Paganetti
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
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Pedretti S, De Santis MC, Vavassori V, Bortolato B, Colciago RR, Cagna E, Doino DP, Cocchi A, Gerardi MA, Alterio D, Magrini SM, Tonoli S. Image-guided radiotherapy (IGRT) in Lombardy, Italy: a survey by the Lombardy section of the Italian Association of Radiotherapy and Clinical Oncology (AIRO-Lombardy). Expert Rev Anticancer Ther 2023; 23:661-667. [PMID: 37129314 DOI: 10.1080/14737140.2023.2208864] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
BACKGROUND Image-guided radiation therapy (IGRT) has changed clinical practice. We proposed a survey to radiotherapy centers in Lombardy to picture the current clinical practice of its use. RESEARCH DESIGN AND METHODS The survey consisted of 32 multiple-choice questions, divided into five topics: type of hospital, patients treated in 2019, number of LINACs; presence of protocols and staff involved in IGRT; IGRT in stereotaxis; IGRT in non-stereotactic treatments; availability of medical and technical staff. RESULTS Twenty-seven directors answered (77%). Most centers (74%) have produced protocols to ensure uniformity in the IGRT process. The most widely used IGRT modality (92%) is cone-beam CT. Daily IGRT control is favored for prostate (100%), head and neck (87%), and lung (78%) neoplasms. The resident doctors can always perform supervised IGRT matching in only six centers. Radiation therapists perform IGRT controls only for some sites in 12 cases (44%) and always in 9 cases (33%). Radiation oncologists are present in real time, in most cases. CONCLUSIONS Today, IGRT can be considered standard practice but at the price of more time-consuming procedures. A balance between a fully physician-controlled process and an increased role for specifically trained RTTs is actively being sought.
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Affiliation(s)
- Sara Pedretti
- Radiation Oncology Department, ASST Spedali Civili di Brescia, Brescia, Italy
| | - Maria Carmen De Santis
- Radiation Oncology Department, Istituto Nazionale per lo Studio e la cura dei tumori, Milano, Italy
| | - Vittorio Vavassori
- Humanitas Gavazzeni Hospital, Radiation Oncology Department, Bergamo, Italy
| | - Barbara Bortolato
- Radiation Oncology Department, ASST della Valle Olona, Busto Arsizio, Italy
| | - Riccardo Ray Colciago
- Radiation Oncology Department, Istituto Nazionale per lo Studio e la cura dei tumori, Milano, Italy
| | - Emanuela Cagna
- Radiation Oncology Department, ASST Lariana, Como, Italy
| | | | | | | | - Daniela Alterio
- Radiation Oncology Department, European Institue of Oncology, Milno, Italy
| | | | - Sandro Tonoli
- Radiation Oncology Department, ASST Cremona, Cremona, Italy
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Zhang X, Sisniega A, Zbijewski WB, Lee J, Jones CK, Wu P, Han R, Uneri A, Vagdargi P, Helm PA, Luciano M, Anderson WS, Siewerdsen JH. Combining physics-based models with deep learning image synthesis and uncertainty in intraoperative cone-beam CT of the brain. Med Phys 2023; 50:2607-2624. [PMID: 36906915 PMCID: PMC10175241 DOI: 10.1002/mp.16351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 02/03/2023] [Accepted: 02/27/2023] [Indexed: 03/13/2023] Open
Abstract
BACKGROUND Image-guided neurosurgery requires high localization and registration accuracy to enable effective treatment and avoid complications. However, accurate neuronavigation based on preoperative magnetic resonance (MR) or computed tomography (CT) images is challenged by brain deformation occurring during the surgical intervention. PURPOSE To facilitate intraoperative visualization of brain tissues and deformable registration with preoperative images, a 3D deep learning (DL) reconstruction framework (termed DL-Recon) was proposed for improved intraoperative cone-beam CT (CBCT) image quality. METHODS The DL-Recon framework combines physics-based models with deep learning CT synthesis and leverages uncertainty information to promote robustness to unseen features. A 3D generative adversarial network (GAN) with a conditional loss function modulated by aleatoric uncertainty was developed for CBCT-to-CT synthesis. Epistemic uncertainty of the synthesis model was estimated via Monte Carlo (MC) dropout. Using spatially varying weights derived from epistemic uncertainty, the DL-Recon image combines the synthetic CT with an artifact-corrected filtered back-projection (FBP) reconstruction. In regions of high epistemic uncertainty, DL-Recon includes greater contribution from the FBP image. Twenty paired real CT and simulated CBCT images of the head were used for network training and validation, and experiments evaluated the performance of DL-Recon on CBCT images containing simulated and real brain lesions not present in the training data. Performance among learning- and physics-based methods was quantified in terms of structural similarity (SSIM) of the resulting image to diagnostic CT and Dice similarity metric (DSC) in lesion segmentation compared to ground truth. A pilot study was conducted involving seven subjects with CBCT images acquired during neurosurgery to assess the feasibility of DL-Recon in clinical data. RESULTS CBCT images reconstructed via FBP with physics-based corrections exhibited the usual challenges to soft-tissue contrast resolution due to image non-uniformity, noise, and residual artifacts. GAN synthesis improved image uniformity and soft-tissue visibility but was subject to error in the shape and contrast of simulated lesions that were unseen in training. Incorporation of aleatoric uncertainty in synthesis loss improved estimation of epistemic uncertainty, with variable brain structures and unseen lesions exhibiting higher epistemic uncertainty. The DL-Recon approach mitigated synthesis errors while maintaining improvement in image quality, yielding 15%-22% increase in SSIM (image appearance compared to diagnostic CT) and up to 25% increase in DSC in lesion segmentation compared to FBP. Clear gains in visual image quality were also observed in real brain lesions and in clinical CBCT images. CONCLUSIONS DL-Recon leveraged uncertainty estimation to combine the strengths of DL and physics-based reconstruction and demonstrated substantial improvements in the accuracy and quality of intraoperative CBCT. The improved soft-tissue contrast resolution could facilitate visualization of brain structures and support deformable registration with preoperative images, further extending the utility of intraoperative CBCT in image-guided neurosurgery.
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Affiliation(s)
- Xiaoxuan Zhang
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Alejandro Sisniega
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Wojciech B. Zbijewski
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Junghoon Lee
- Department of Radiation Oncology, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Craig K. Jones
- Department of Computer Science, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Pengwei Wu
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Runze Han
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Ali Uneri
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Prasad Vagdargi
- Department of Computer Science, Johns Hopkins University, Baltimore, MD 21218, USA
| | | | - Mark Luciano
- Department of Neurosurgery, Johns Hopkins Hospital, Baltimore, MD 21218, USA
| | - William S. Anderson
- Department of Neurosurgery, Johns Hopkins Hospital, Baltimore, MD 21218, USA
| | - Jeffrey H. Siewerdsen
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD 21218, USA
- Department of Computer Science, Johns Hopkins University, Baltimore, MD 21218, USA
- Department of Neurosurgery, Johns Hopkins Hospital, Baltimore, MD 21218, USA
- Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030
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Vasoglou G, Lyros I, Patatou A, Vasoglou M. Orthodontic Treatment of Palatally Impacted Maxillary Canines with the Use of a Digitally Designed and 3D-Printed Metal Device. Dent J (Basel) 2023; 11:dj11040102. [PMID: 37185480 PMCID: PMC10137553 DOI: 10.3390/dj11040102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Revised: 03/21/2023] [Accepted: 04/06/2023] [Indexed: 05/17/2023] Open
Abstract
The purpose of this article is to present a computer designed and 3D-printed metal device, which was used for the surgical exposure and orthodontic treatment of maxillary palatally impacted canines. In two cases which presented a palatally impacted canine, a Cone-Beam Computed Tomography (CBCT) was acquired and an intraoral scanning was performed, to determine the exact location of the canine. Based on a digital model, a device leaning on the teeth and mucosa was designed to serve as a guiding tool for the oral surgeon to expose the crown of the canine and help the orthodontist to provide proper traction. The device was then 3D-printed in biocompatible dental alloy and placed in the patients' mouth. After the surgical exposure of the canine's crown in both cases, a gold chain apparatus was bonded on and it was mounted on the metal projection of the device through an elastic chain. Within 3 months of traction, the crown of the canines appeared in the patients' palate to the exact location that was predicted and guided. A 3D-designed and manufactured metal device, with information acquired by CBCT and intraoral scanning, can be used for the exposure and traction of palatally impacted canines.
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Affiliation(s)
| | - Ioannis Lyros
- Department of Orthodontics, School of Dentistry, National and Kapodistrian University of Athens, 11527 Athens, Greece
| | | | - Michail Vasoglou
- Private Orthodontic Practice, 17676 Athens, Greece
- Department of Orthodontics, School of Dentistry, National and Kapodistrian University of Athens, 11527 Athens, Greece
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Lee H, Cheon BW, Feld JW, Grogg K, Perl J, Ramos-Méndez JA, Faddegon B, Min CH, Paganetti H, Schuemann J. TOPAS-imaging: extensions to the TOPAS simulation toolkit for medical imaging systems. Phys Med Biol 2023; 68:10.1088/1361-6560/acc565. [PMID: 36930985 PMCID: PMC10164408 DOI: 10.1088/1361-6560/acc565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Accepted: 03/17/2023] [Indexed: 03/19/2023]
Abstract
Objective. The TOol for PArticle Simulation (TOPAS) is a Geant4-based Monte Carlo software application that has been used for both research and clinical studies in medical physics. So far, most users of TOPAS have focused on radiotherapy-related studies, such as modeling radiation therapy delivery systems or patient dose calculation. Here, we present the first set of TOPAS extensions to make it easier for TOPAS users to model medical imaging systems.Approach. We used the extension system of TOPAS to implement pre-built, user-configurable geometry components such as detectors (e.g. flat-panel and multi-planar detectors) for various imaging modalities and pre-built, user-configurable scorers for medical imaging systems (e.g. digitizer chain).Main results. We developed a flexible set of extensions that can be adapted to solve research questions for a variety of imaging modalities. We then utilized these extensions to model specific examples of cone-beam CT (CBCT), positron emission tomography (PET), and prompt gamma (PG) systems. The first of these new geometry components, the FlatImager, was used to model example CBCT and PG systems. Detected signals were accumulated in each detector pixel to obtain the intensity of x-rays penetrating objects or prompt gammas from proton-nuclear interaction. The second of these new geometry components, the RingImager, was used to model an example PET system. Positron-electron annihilation signals were recorded in crystals of the RingImager and coincidences were detected. The simulated data were processed using corresponding post-processing algorithms for each modality and obtained results in good agreement with the expected true signals or experimental measurement.Significance. The newly developed extension is a first step to making it easier for TOPAS users to build and simulate medical imaging systems. Together with existing TOPAS tools, this extension can help integrate medical imaging systems with radiotherapy simulations for image-guided radiotherapy.
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Affiliation(s)
- Hoyeon Lee
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, United States of America
| | - Bo-Wi Cheon
- Department of Radiation Convergence Engineering, Yonsei University, Wonju, Gangwon-do 26493, Republic of Korea
| | - Joseph W Feld
- Electrical Engineering and Computer Science Department, Massachusetts Institute of Technology, Cambridge, MA 02139, United States of America
| | - Kira Grogg
- The Gordon Center for Medical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, United States of America
| | - Joseph Perl
- SLAC National Accelerator Laboratory, Menlo Park, CA 94025 United States of America
| | - José A Ramos-Méndez
- Department of Radiation Oncology, University of California San Francisco, San Francisco, CA 94115 United States of America
| | - Bruce Faddegon
- Department of Radiation Oncology, University of California San Francisco, San Francisco, CA 94115 United States of America
| | - Chul Hee Min
- Department of Radiation Convergence Engineering, Yonsei University, Wonju, Gangwon-do 26493, Republic of Korea
| | - Harald Paganetti
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, United States of America
| | - Jan Schuemann
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, United States of America
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Mahasneh SA, Al-Hadidi A, Kadim Wahab F, Sawair FA, Al-Rabab'ah MA, Al-Nazer S, Bakain Y, Nardi C, Cunliffe J. A Cone Beam CT Study on the Correlation between Crestal Bone Loss and Periapical Disease. J Clin Med 2023; 12:jcm12062423. [PMID: 36983422 PMCID: PMC10053371 DOI: 10.3390/jcm12062423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 03/15/2023] [Accepted: 03/20/2023] [Indexed: 03/30/2023] Open
Abstract
The aim of this study was to determine whether the degree of bone loss around teeth can be linked to the loss of vitality of adjacent teeth and periapical disease, which necessitates root canal treatments. Three hundred and twenty-one full maxilla cone-beam computed tomography scans were examined. The parameters investigated included the degree of crestal bone loss in relation to the cementoenamel junction, the presence/absence of apical periodontitis, and the presence/absence of root canal treatments. Out of the 2001 teeth examined, 696 (34.8%) showed evidence of crestal bone loss. The degree of crestal bone loss was classified as mild, moderate, or severe. A significant association (p < 0.001) was found between the presence of crestal bone loss around a tooth and root canal treatment of that tooth. It was found that it is more likely for teeth with crestal bone loss to be root canal treated compared to teeth with existing root canal treatment and healthy crestal bone levels. Furthermore, teeth with buccal or lingual crestal bone loss were significantly associated with a higher rate of periapical disease than teeth without crestal bone loss (p < 0.001). CBCT identified the severity of bone loss on all surfaces of the teeth, and the most common presentation was bone loss to the mid-root level. Teeth with crestal bone loss were significantly more likely to be associated with a higher rate of periapical disease. Teeth with crestal bone loss were more likely to be root treated than teeth with healthy crestal bone levels.
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Affiliation(s)
- Sari A Mahasneh
- School of Dentistry, University of Jordan, Amman 11942, Jordan
- Division of Dentistry, School of Medical Sciences, University of Manchester, Manchester M13 9PL, UK
| | - Abeer Al-Hadidi
- School of Dentistry, University of Jordan, Amman 11942, Jordan
| | | | - Faleh A Sawair
- School of Dentistry, University of Jordan, Amman 11942, Jordan
| | | | | | | | - Cosimo Nardi
- Department of Experimental and Clinical Biomedical Sciences, Radiodiagnostic Unit n. 2, University of Florence-Azienda Ospedaliero-Universitaria Careggi, 50134 Florence, Italy
| | - Joanne Cunliffe
- Division of Dentistry, School of Medical Sciences, University of Manchester, Manchester M13 9PL, UK
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Ravikumar N, Ho E, Wagh A, Murgu S. Advanced Imaging for Robotic Bronchoscopy: A Review. Diagnostics (Basel) 2023; 13. [PMID: 36900134 DOI: 10.3390/diagnostics13050990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Revised: 02/27/2023] [Accepted: 02/28/2023] [Indexed: 03/08/2023] Open
Abstract
Recent advances in navigational platforms have led bronchoscopists to make major strides in diagnostic interventions for pulmonary parenchymal lesions. Over the last decade, multiple platforms including electromagnetic navigation and robotic bronchoscopy have allowed bronchoscopists to safely navigate farther into the lung parenchyma with increased stability and accuracy. Limitations persist, even with these newer technologies, in achieving a similar or higher diagnostic yield when compared to the transthoracic computed tomography (CT) guided needle approach. One of the major limitations to this effect is due to CT-to-body divergence. Real-time feedback that better defines the tool-lesion relationship is vital and can be obtained with additional imaging using radial endobronchial ultrasound, C-arm based tomosynthesis, cone-beam CT (fixed or mobile), and O-arm CT. Herein, we describe the role of this adjunct imaging with robotic bronchoscopy for diagnostic purposes, describe potential strategies to counteract the CT-to-body divergence phenomenon, and address the potential role of advanced imaging for lung tumor ablation.
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Qin P, Lin G, Li X, Piao Z, Huang S, Wu W, Qi M, Ma J, Zhou L, Xu Y. A correlated sampling-based Monte Carlo simulation for fast CBCT iterative scatter correction. Med Phys 2023; 50:1466-1480. [PMID: 36323626 DOI: 10.1002/mp.16073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 10/03/2022] [Accepted: 10/24/2022] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND In recent years, cone-beam computed tomography (CBCT) has played an important role in medical imaging. However, the applications of CBCT are limited due to the severe scatter contamination. Conventional Monte Carlo (MC) simulation can provide accurate scatter estimation for scatter correction, but the expensive computational cost has always been the bottleneck of MC method in clinical application. PURPOSE In this work, an MC simulation method combined with a variance reduction technique called correlated sampling is proposed for fast iterative scatter correction. METHODS Correlated sampling exploits correlation between similar simulation systems to reduce the variance of interest quantities. Specifically, conventional MC simulation is first performed on the scatter-contaminated CBCT to generate the initial scatter signal. In the subsequent correction iterations, scatter estimation is then updated by applying correlated MC sampling to the latest corrected CBCT images by reusing the random number sequences of the task-related photons in conventional MC. Afterward, the corrected projections obtained by subtracting the scatter estimation from raw projections are utilized for FDK reconstruction. These steps are repeated until an adequate scatter correction is obtained. The performance of the proposed framework is evaluated by the accuracy of the scatter estimation, the quality of corrected CBCT images and efficiency. RESULTS Overall, the difference in mean absolute percentage error between scatter estimation with and without correlated sampling is 0.25% for full-fan case and 0.34% for half-fan case, respectively. In simulation studies, scatter artifacts are substantially eliminated, where the mean absolute error value is reduced from 15 to 2 HU in full-fan case and from 53 to 13 HU in half-fan case. Scatter-to-primary ratio is reduced to 0.02 for full-fan and 0.04 for half-fan, respectively. In phantom study, the contrast-to-noise ratio (CNR) is increased by a factor of 1.63, and the contrast is increased by a factor of 1.77. As for clinical studies, the CNR is improved by 11% and 14% for half-fan and full-fan, respectively. The contrast after correction is increased by 19% for half-fan and 44% for full-fan. Furthermore, root mean square error is also effectively reduced, especially from 78 to 4 HU for full-fan. Experimental results demonstrate that the figure of merit is improved between 23 and 43 folds when using correlated sampling. The proposed method takes less than 25 s for the whole iterative scatter correction process. CONCLUSIONS The proposed correlated sampling-based MC simulation method can achieve fast and accurate scatter correction for CBCT, making it suitable for real-time clinical use.
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Affiliation(s)
- Peishan Qin
- School of Biomedical Engineering, Southern Medical University, Guangzhou, Guangdong, China
| | - Guoqin Lin
- School of Biomedical Engineering, Southern Medical University, Guangzhou, Guangdong, China
| | - Xu Li
- School of Biomedical Engineering, Southern Medical University, Guangzhou, Guangdong, China
| | - Zun Piao
- School of Biomedical Engineering, Southern Medical University, Guangzhou, Guangdong, China
| | - Shuang Huang
- School of Biomedical Engineering, Southern Medical University, Guangzhou, Guangdong, China
| | - WangJiang Wu
- School of Biomedical Engineering, Southern Medical University, Guangzhou, Guangdong, China
| | - Mengke Qi
- School of Biomedical Engineering, Southern Medical University, Guangzhou, Guangdong, China
| | - Jianhui Ma
- School of Biomedical Engineering, Southern Medical University, Guangzhou, Guangdong, China
| | - Linghong Zhou
- School of Biomedical Engineering, Southern Medical University, Guangzhou, Guangdong, China
| | - Yuan Xu
- School of Biomedical Engineering, Southern Medical University, Guangzhou, Guangdong, China
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Zhang Y, Shao HC, Pan T, Mengke T. Dynamic cone-beam CT reconstruction using spatial and temporal implicit neural representation learning (STINR). Phys Med Biol 2023; 68:045005. [PMID: 36638543 PMCID: PMC10087494 DOI: 10.1088/1361-6560/acb30d] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 12/27/2022] [Accepted: 01/13/2023] [Indexed: 01/15/2023]
Abstract
Objective. Dynamic cone-beam CT (CBCT) imaging is highly desired in image-guided radiation therapy to provide volumetric images with high spatial and temporal resolutions to enable applications including tumor motion tracking/prediction and intra-delivery dose calculation/accumulation. However, dynamic CBCT reconstruction is a substantially challenging spatiotemporal inverse problem, due to the extremely limited projection sample available for each CBCT reconstruction (one projection for one CBCT volume).Approach. We developed a simultaneous spatial and temporal implicit neural representation (STINR) method for dynamic CBCT reconstruction. STINR mapped the unknown image and the evolution of its motion into spatial and temporal multi-layer perceptrons (MLPs), and iteratively optimized the neuron weightings of the MLPs via acquired projections to represent the dynamic CBCT series. In addition to the MLPs, we also introduced prior knowledge, in the form of principal component analysis (PCA)-based patient-specific motion models, to reduce the complexity of the temporal mapping to address the ill-conditioned dynamic CBCT reconstruction problem. We used the extended-cardiac-torso (XCAT) phantom and a patient 4D-CBCT dataset to simulate different lung motion scenarios to evaluate STINR. The scenarios contain motion variations including motion baseline shifts, motion amplitude/frequency variations, and motion non-periodicity. The XCAT scenarios also contain inter-scan anatomical variations including tumor shrinkage and tumor position change.Main results. STINR shows consistently higher image reconstruction and motion tracking accuracy than a traditional PCA-based method and a polynomial-fitting-based neural representation method. STINR tracks the lung target to an average center-of-mass error of 1-2 mm, with corresponding relative errors of reconstructed dynamic CBCTs around 10%.Significance. STINR offers a general framework allowing accurate dynamic CBCT reconstruction for image-guided radiotherapy. It is a one-shot learning method that does not rely on pre-training and is not susceptible to generalizability issues. It also allows natural super-resolution. It can be readily applied to other imaging modalities as well.
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Affiliation(s)
- You Zhang
- Advanced Imaging and Informatics in Radiation Therapy (AIRT) Laboratory, Medical Artificial Intelligence and Automation (MAIA) Laboratory, Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, TX, 75235, United States of America
| | - Hua-Chieh Shao
- Advanced Imaging and Informatics in Radiation Therapy (AIRT) Laboratory, Medical Artificial Intelligence and Automation (MAIA) Laboratory, Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, TX, 75235, United States of America
| | - Tinsu Pan
- Department of Imaging Physics, University of Texas MD Anderson Cancer Center, Houston, TX, 77030, United States of America
| | - Tielige Mengke
- Advanced Imaging and Informatics in Radiation Therapy (AIRT) Laboratory, Medical Artificial Intelligence and Automation (MAIA) Laboratory, Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, TX, 75235, United States of America
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26
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Huang H, Siewerdsen JH, Lu A, Hu Y, Zbijewski W, Unberath M, Weiss CR, Sisniega A. Multi-Stage Adaptive Spline Autofocus (MASA) with a Learned Metric for Deformable Motion Compensation in Interventional Cone-Beam CT. Proc SPIE Int Soc Opt Eng 2023; 12463:1246314. [PMID: 37937146 PMCID: PMC10629227 DOI: 10.1117/12.2654361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2023]
Abstract
Purpose Cone-beam CT (CBCT) is widespread in abdominal interventional imaging, but its long acquisition time makes it susceptible to patient motion. Image-based autofocus has shown success in CBCT deformable motion compensation, via deep autofocus metrics and multi-region optimization, but it is challenged by the large parameter dimensionality required to capture intricate motion trajectories. This work leverages the differentiable nature of deep autofocus metrics to build a novel optimization strategy, Multi-Stage Adaptive Spine Autofocus (MASA), for compensation of complex deformable motion in abdominal CBCT. Methods MASA poses the autofocus problem as a multi-stage adaptive sampling strategy of the motion trajectory, sampled with Hermite spline basis with variable amplitude and knot temporal positioning. The adaptive method permits simultaneous optimization of the sampling phase, local temporal sampling density, and time-dependent amplitude of the motion trajectory. The optimization is performed in a multi-stage schedule with increasing number of knots that progressively accommodates complex trajectories in late stages, preconditioned by coarser components from early stages, and with minimal increase in dimensionality. MASA was evaluated in controlled simulation experiments with two types of motion trajectories: i) combinations of slow drifts with sudden jerk (sigmoid) motion; and ii) combinations of periodic motion sources of varying frequency into multi-frequency trajectories. Further validation was obtained in clinical data from liver CBCT featuring motion of contrast-enhanced vessels, and soft-tissue structures. Results The adaptive sampling strategy provided successful motion compensation in sigmoid trajectories, compared to fixed sampling strategies (mean SSIM increase of 0.026 compared to 0.011). Inspection of the estimated motion showed the capability of MASA to automatically allocate larger sampling density to parts of the scan timeline featuring sudden motion, effectively accommodating complex motion without increasing the problem dimension. Experiments on multi-frequency trajectories with 3-stage MASA (5, 10, and 15 knots) yielded a twofold SSIM increase compared to single-stage autofocus with 15 knots (0.076 vs 0.040, respectively). Application of MASA to clinical datasets resulted in simultaneous improvement on the delineation of both contrast-enhanced vessels and soft-tissue structures in the liver. Conclusion A new autofocus framework, MASA, was developed including a novel multi-stage technique for adaptive temporal sampling of the motion trajectory in combination with fully differentiable deep autofocus metrics. This novel adaptive sampling approach is a crucial step for application of deformable motion compensation to complex temporal motion trajectories.
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Affiliation(s)
- H Huang
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD USA
| | - J H Siewerdsen
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD USA
- Russell H. Morgan Department of Radiology, Johns Hopkins University, Baltimore, MD USA
- Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston TX USA
| | - A Lu
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD USA
| | - Y Hu
- Department of Computer Science, Johns Hopkins University, Baltimore, MD USA
| | - W Zbijewski
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD USA
| | - M Unberath
- Department of Computer Science, Johns Hopkins University, Baltimore, MD USA
| | - C R Weiss
- Russell H. Morgan Department of Radiology, Johns Hopkins University, Baltimore, MD USA
| | - A Sisniega
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD USA
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Liu SZ, Zhou H, Osgood GM, Demehri S, Stayman JW, Zbijewski W. Quantitative Dual-Energy Imaging of Bone Marrow Edema Using Multisource Cone-Beam CT with Model-Based Decomposition. Proc SPIE Int Soc Opt Eng 2023; 12463:1246315. [PMID: 38226341 PMCID: PMC10788134 DOI: 10.1117/12.2654449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2024]
Abstract
Purpose We investigated the feasibility of dual-energy (DE) detection of bone marrow edema (BME) using a dedicated extremity cone-beam CT (CBCT) with a unique three-source x-ray unit. The sources can be operated at different energies to enable single-scan DE acquisitions. However, they are arranged parallel to the axis of rotation, resulting in incomplete sampling and precluding the application of DE projection-domain decompositions (PDD) for beam-hardening reduction. Therefore, we propose a novel combination of a model-based "one-step" DE two-material decomposition followed by a constrained image-domain change-of-basis to obtain virtual non-calcium (VNCa) images for BME detection. Methods DE projections were obtained using an "alternating-kV" protocol by operating the peripheral two sources of the CBCT system at low-energy (60 kV, 0.105 mAs/frame) and the central source at high-energy (100 kV, 0.028 mAs/frame), for a total of 600 frames over 216° of gantry rotation. Projections were processed with detector lag, glare and fast Monte Carlo (MC)-based iterative scatter corrections. Model-based material decomposition (MBMD) was then implemented to obtain aluminum (Al) and polyethylene (PE) volume fraction images with minimal beam-hardening. Statistical ray weights in MBMD were modified to account for regions with highly oblique sampling by the peripheral sources. To generate the VNCa maps, image-domain decomposition (IDD) constrained by the volume conservation principle (VCP) was performed to convert the Al and PE MBMD images into volume fractions of water, fat and cortical bone. Accuracy of BME detection was evaluated using physical phantom data acquired on the multi-source extremity CBCT scanner. Results The proposed framework estimated the volume of BME with ~10% error. The MC-based scatter corrections and the modified MBMD ray weights were essential to achieve such performance - the error without MC scatter corrections was >30%, whereas the uniformity of estimated VNCa images was 3x improved using the modified weights compared to the conventional weights. Conclusions The proposed DE decomposition framework was able to overcome challenges of high scatter and incomplete sampling to achieve BME detection on a CBCT system with axially-distributed x-ray sources.
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Affiliation(s)
- Stephen Z. Liu
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD 21205
| | - Huanyi Zhou
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD 21205
| | - Greg M. Osgood
- Department of Orthopedic Surgery, Johns Hopkins Hospital, Baltimore, MD 21205
| | - Shadpour Demehri
- Russell H. Morgan Department of Radiology, Johns Hopkins Hospital, Baltimore, MD 21205
| | - J. Webster Stayman
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD 21205
| | - Wojciech Zbijewski
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD 21205
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Li G, Chen X, You C, Huang X, Deng Z, Luo S. A nonconvex model-based combined geometric calibration scheme for micro cone-beam CT with irregular trajectories. Med Phys 2023; 50:2759-2774. [PMID: 36718546 DOI: 10.1002/mp.16257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2022] [Revised: 12/21/2022] [Accepted: 01/17/2023] [Indexed: 02/01/2023] Open
Abstract
BACKGROUND Many dedicated cone-beam CT (CBCT) systems have irregular scanning trajectories. Compared with the standard CBCT calibration, accurate calibration for CBCT systems with irregular trajectories is a more complex task, since the geometric parameters for each scanning view are variable. Most of the existing calibration methods assume that the intrinsic geometric relationship of the fiducials in the phantom is precisely known, and rarely delve deeper into the issue of whether the phantom accuracy is adapted to the calibration model. PURPOSE A high-precision phantom and a highly robust calibration model are interdependent and mutually supportive, and they are both important for calibration accuracy, especially for the high-resolution CBCT. Therefore, we propose a calibration scheme that considers both accurate phantom measurement and robust geometric calibration. METHODS Our proposed scheme consists of two parts: (1) introducing a measurement model to acquire the accurate intrinsic geometric relationship of the fiducials in the phantom; (2) developing a highly noise-robust nonconvex model-based calibration method. The measurement model in the first part is achieved by extending our previous high-precision geometric calibration model suitable for CBCT with circular trajectories. In the second part, a novel iterative method with optimization constraints based on a back-projection model is developed to solve the geometric parameters of each view. RESULTS The simulations and real experiments show that the measurement errors of the fiducial ball bearings (BBs) are within the subpixel level. With the help of the geometric relationship of the BBs obtained by our measurement method, the classic calibration method can achieve good calibration based on far fewer BBs. All metrics obtained in simulated experiments as well as in real experiments on Micro CT systems with resolutions of 9 and 4.5 μm show that the proposed calibration method has higher calibration accuracy than the competing classic method. It is particularly worth noting that although our measurement model proves to be very accurate, the classic calibration method based on this measurement model can only achieve good calibration results when the resolution of the measurement system is close to that of the system to be calibrated, but our calibration scheme enables high-accuracy calibration even when the resolution of the system to be calibrated is twice that of the measurement system. CONCLUSIONS The proposed combined geometrical calibration scheme does not rely on a phantom with an intricate pattern of fiducials, so it is applicable in Micro CT with high resolution. The two parts of the scheme, the "measurement model" and the "calibration model," prove to be of high accuracy. The combination of these two models can effectively improve the calibration accuracy, especially in some extreme cases.
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Affiliation(s)
- Guang Li
- Jiangsu Key Laboratory for Biomaterials and Devices, Department of Biomedical Engineering, Southeast University, Nanjing, China
| | - Xue Chen
- Jiangsu Key Laboratory for Biomaterials and Devices, Department of Biomedical Engineering, Southeast University, Nanjing, China
| | - Chenyu You
- Image Processing and Analysis Group (IPAG), Yale University, New Haven, Connecticut, USA
| | - Xinhai Huang
- Jiangsu Key Laboratory for Biomaterials and Devices, Department of Biomedical Engineering, Southeast University, Nanjing, China
| | - Zhenhao Deng
- Jiangsu Key Laboratory for Biomaterials and Devices, Department of Biomedical Engineering, Southeast University, Nanjing, China
| | - Shouhua Luo
- Jiangsu Key Laboratory for Biomaterials and Devices, Department of Biomedical Engineering, Southeast University, Nanjing, China
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Cobos SF, Norley CJ, Nikolov HN, Holdsworth DW. 3D-printed large-area focused grid for scatter reduction in cone-beam CT. Med Phys 2023; 50:240-258. [PMID: 36215176 DOI: 10.1002/mp.16005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 08/19/2022] [Accepted: 09/07/2022] [Indexed: 01/25/2023] Open
Abstract
BACKGROUND Cone-beam computed tomography (CBCT) systems acquire volumetric data more efficiently than fan-beam or multislice CT, particularly when the anatomy of interest resides within the axial field-of-view of the detector and data can be acquired in one rotation. For such systems, scattered radiation remains a source of image quality degradation leading to increased noise, image artifacts, and CT number inaccuracies. PURPOSE Recent advances in metal additive manufacturing allow the production of highly focused antiscatter grids (2D-ASGs) that can be used to reduce scatter intensity, while preserving primary radiation transmission. We present the first implementation of a large-area, 2D-ASG for flat-panel CBCT, including grid-line artifact removal and related improvements in image quality. METHODS A 245 × 194 × 10 mm 2D-ASG was manufactured from chrome-cobalt alloy using laser powder-bed fusion (LPBF) (AM-400; Renishaw plc, New Mills Wotton-under-Edge, UK). The 2D-ASG had a square profile with a pitch of 9.09 lines/cm and 10:1 grid-ratio. The nominal 0.1 mm grid septa were focused to a 732 mm x-ray source to optimize primary x-ray transmission and reduce grid-line shadowing at the detector. Powder-bed fusion ensured the structural stability of the ASG with no need for additional interseptal support. The 2D-ASG was coupled to a 0.139-mm element pitch flat-panel detector (DRX 3543, Carestream Health) and proper alignment was confirmed by consistent grid-line shadow thickness across the whole detector array. A 154-mm diameter CBCT image-quality-assurance phantom was imaged using a rotary stage and a ceiling-mounted, x-ray unit (Proteus XR/a, GE Medical Systems, 80kVp, 0.5mAs). Grid-line artifacts were removed using a combination of exposure-dependent gain correction and spatial-frequency, Fourier filtering. Projections were reconstructed using a Parker-weighted, FDK algorithm and voxels were spatially averaged to 357 × 357 × 595 µm to improve the signal-to-noise characteristics of the CBCT reconstruction. Finally, in order to compare image quality with and without scatter, the phantom was scanned again under the same CBCT conditions but with no 2D-ASG. No additional antiscatter (i.e., air-gap, bowtie filtration) strategies were used to evaluate the effects in image quality caused by the 2D-ASG alone. RESULTS The large-area, 2D-ASG prototype was successfully designed and manufactured using LPBF. CBCT image-quality improvements using the 2D-ASG included: an overall 14.5% CNR increase across the volume; up to 48.8% CNR increase for low-contrast inserts inside the contrast plate of the QA phantom; and a 65% reduction of cupping artifact in axial profiles of water-filled cross sections of the phantom. Advanced image processing strategies to remove grid line artifacts did not affect the spatial resolution or geometric accuracy of the system. CONCLUSIONS LPBF can be used to manufacture highly efficient, 2D-focused ASGs that can be easily coupled to clinical, flat-panel detectors. The implementation of ASGs in CBCT leads to reduced scatter-related artifacts, improved CT number accuracy, and enhanced CNR with no increased equivalent dose to the patient. Further improvements to image quality might be achieved with a combination of scatter-correction algorithms and iterative-reconstruction strategies. Finally, clinical applications where other scatter removal strategies are unfeasible might now achieve superior soft-tissue visualization and quantitative capabilities.
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Affiliation(s)
| | | | | | - David Wayne Holdsworth
- Department of Medical Biophysics, Western University, London, Ontario, Canada.,Robarts Research Institute, Western University, London, Ontario, Canada
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DE Cicco L, Marzoli L, Lorusso R, Mancuso RM, Petazzi E, Lanceni AG, Della Bosca E, Buttignol S, Starace A, Verusio C, Bortolato B. CBCT-based Prostate IGRT With and Without Implanted Markers: Assessment of Geometric Corrections and Time for Completion. Anticancer Res 2023; 43:405-408. [PMID: 36585214 DOI: 10.21873/anticanres.16175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 11/30/2022] [Accepted: 12/05/2022] [Indexed: 01/01/2023]
Abstract
BACKGROUND/AIM Cone-beam computed tomography (CBCT) is the most commonly used system in modern radiotherapy of prostate cancer for daily positioning verification. The use of intraprostatic radiopaque fiducials (FMs) may be added to CBCT. We wanted to investigate the possible advantage of using FMs in daily CBCT repositioning. MATERIALS AND METHODS We selected three CBCTs for each treatment course for 13 patients (seven with and six without use of FMs) treated at our centre. Seven experienced Radiation Oncologists retrospectively reviewed the CBCTs, recording couch movements for correct patient positioning, and time spent to do it. Analysis of variance and t-test were carried out for comparison of different groups and for differences in mean values of the movements recorded (with p<0.05 as significance level). RESULTS No statistically significant difference was found between operators in the analysis of images with FMs nor of images without them. A difference was only found in the mean corrections in couch rotation and pitch angle, which were higher in the FM group, and in the mean time for image analysis, which was shorter in this group. Using the van Herk formula, we found a possible reduction of clinical target volume and planning target volume margins for the FM group. CONCLUSION According to our study, the use of intraprostatic FMs in daily CBCT seems useful for better detection of and correction for non-negligible rotational errors. Furthermore, FMs reduced the time to treatment start, which is very important in reducing the risk of intrafraction organ motion. These results need to be confirmed by further studies.
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Affiliation(s)
- Luigi DE Cicco
- Division of Radiotherapy, ASST Valle Olona, Busto Arsizio, Italy;
| | - Luca Marzoli
- Division of Medical Physics, ASST Valle Olona, Busto Arsizio, Italy
| | - Rita Lorusso
- Division of Medical Physics, ASST Valle Olona, Busto Arsizio, Italy
| | | | - Elena Petazzi
- Division of Radiotherapy, ASST Valle Olona, Busto Arsizio, Italy
| | | | | | - Sandra Buttignol
- Division of Radiotherapy, ASST Valle Olona, Busto Arsizio, Italy
| | - Antonio Starace
- Division of Radiotherapy, ASST Valle Olona, Busto Arsizio, Italy
| | - Claudio Verusio
- Division of Oncological, Hospital Unit of Saronno, ASST Valle Olona, Busto Arsizio, Italy
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31
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de Bataille C, Bernard D, Dumoncel J, Vaysse F, Cussat-Blanc S, Telmon N, Maret D, Monsarrat P. Machine Learning Analysis of the Anatomical Parameters of the Upper Airway Morphology: A Retrospective Study from Cone-Beam CT Examinations in a French Population. J Clin Med 2022; 12:84. [PMID: 36614885 PMCID: PMC9820916 DOI: 10.3390/jcm12010084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 12/12/2022] [Accepted: 12/12/2022] [Indexed: 12/24/2022] Open
Abstract
The objective of this study is to assess, using cone-beam CT (CBCT) examinations, the correlation between hard and soft anatomical parameters and their impact on the characteristics of the upper airway using symbolic regression as a machine learning strategy. Methods: On each CBCT, the upper airway was segmented, and 24 anatomical landmarks were positioned to obtain six angles and 19 distances. Some anatomical landmarks were related to soft tissues and others were related to hard tissues. To explore which variables were the most influential to explain the morphology of the upper airway, principal component and symbolic regression analyses were conducted. Results: In total, 60 CBCT were analyzed from subjects with a mean age of 39.5 ± 13.5 years. The intra-observer reproducibility for each variable was between good and excellent. The horizontal soft palate measure mostly contributed to the reduction of the airway volume and minimal section area with a variable importance of around 50%. The tongue and the position of the hyoid bone were also linked to the upper airway morphology. For hard anatomical structures, the anteroposterior position of the mandible and the maxilla had some influence. Conclusions: Although the volume of the airway is not accessible on all CBCT scans performed by dental practitioners, this study demonstrates that a small number of anatomical elements may be markers of the reduction of the upper airway with, potentially, an increased risk of obstructive sleep apnea. This could help the dentist refer the patient to a suitable physician.
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Affiliation(s)
- Caroline de Bataille
- Laboratoire Centre d’Anthropobiologie et de Génomique de Toulouse, Université Paul Sabatier, 31073 Toulouse, France
- School of Dental Medicine and CHU de Toulouse—Toulouse Institute of Oral Medicine and Science, 31062 Toulouse, France
| | - David Bernard
- Institute of Research in Informatics (IRIT) of Toulouse, CNRS—UMR5505, 31062 Toulouse, France
- RESTORE Research Center, Department of Oral Medicine, Université de Toulouse, INSERM, CNRS, EFS, ENVT, Université P. Sabatier, Toulouse University Hospital (CHU), Batiment INCERE, 4bis Avenue Hubert Curien, 31100 Toulouse, France
| | - Jean Dumoncel
- Laboratoire Centre d’Anthropobiologie et de Génomique de Toulouse, Université Paul Sabatier, 31073 Toulouse, France
| | - Frédéric Vaysse
- Laboratoire Centre d’Anthropobiologie et de Génomique de Toulouse, Université Paul Sabatier, 31073 Toulouse, France
- School of Dental Medicine and CHU de Toulouse—Toulouse Institute of Oral Medicine and Science, 31062 Toulouse, France
| | - Sylvain Cussat-Blanc
- Institute of Research in Informatics (IRIT) of Toulouse, CNRS—UMR5505, 31062 Toulouse, France
- Artificial and Natural Intelligence Toulouse Institute ANITI, 31013 Toulouse, France
| | - Norbert Telmon
- Laboratoire Centre d’Anthropobiologie et de Génomique de Toulouse, Université Paul Sabatier, 31073 Toulouse, France
- Service de Médecine Légale, Centre Hospitalier Universitaire Rangueil, Avenue du Professeur Jean Poulhès, CEDEX 9, 31059 Toulouse, France
| | - Delphine Maret
- Laboratoire Centre d’Anthropobiologie et de Génomique de Toulouse, Université Paul Sabatier, 31073 Toulouse, France
- School of Dental Medicine and CHU de Toulouse—Toulouse Institute of Oral Medicine and Science, 31062 Toulouse, France
| | - Paul Monsarrat
- School of Dental Medicine and CHU de Toulouse—Toulouse Institute of Oral Medicine and Science, 31062 Toulouse, France
- RESTORE Research Center, Department of Oral Medicine, Université de Toulouse, INSERM, CNRS, EFS, ENVT, Université P. Sabatier, Toulouse University Hospital (CHU), Batiment INCERE, 4bis Avenue Hubert Curien, 31100 Toulouse, France
- Artificial and Natural Intelligence Toulouse Institute ANITI, 31013 Toulouse, France
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Vijayan R, Sheth N, Mekki L, Lu A, Uneri A, Sisniega A, Magaraggia J, Kleinszig G, Vogt S, Thiboutot J, Lee H, Yarmus L, Siewerdsen JH. 3D-2D image registration in the presence of soft-tissue deformation in image-guided transbronchial interventions. Phys Med Biol 2022; 68. [PMID: 36317269 DOI: 10.1088/1361-6560/ac9e3c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 10/27/2022] [Indexed: 11/06/2022]
Abstract
Purpose. Target localization in pulmonary interventions (e.g. transbronchial biopsy of a lung nodule) is challenged by deformable motion and may benefit from fluoroscopic overlay of the target to provide accurate guidance. We present and evaluate a 3D-2D image registration method for fluoroscopic overlay in the presence of tissue deformation using a multi-resolution/multi-scale (MRMS) framework with an objective function that drives registration primarily by soft-tissue image gradients.Methods. The MRMS method registers 3D cone-beam CT to 2D fluoroscopy without gating of respiratory phase by coarse-to-fine resampling and global-to-local rescaling about target regions-of-interest. A variation of the gradient orientation (GO) similarity metric (denotedGO') was developed to downweight bone gradients and drive registration via soft-tissue gradients. Performance was evaluated in terms of projection distance error at isocenter (PDEiso). Phantom studies determined nominal algorithm parameters and capture range. Preclinical studies used a freshly deceased, ventilated porcine specimen to evaluate performance in the presence of real tissue deformation and a broad range of 3D-2D image mismatch.Results. Nominal algorithm parameters were identified that provided robust performance over a broad range of motion (0-20 mm), including an adaptive parameter selection technique to accommodate unknown mismatch in respiratory phase. TheGO'metric yielded median PDEiso= 1.2 mm, compared to 6.2 mm for conventionalGO.Preclinical studies with real lung deformation demonstrated median PDEiso= 1.3 mm with MRMS +GO'registration, compared to 2.2 mm with a conventional transform. Runtime was 26 s and can be reduced to 2.5 s given a prior registration within ∼5 mm as initialization.Conclusions. MRMS registration via soft-tissue gradients achieved accurate fluoroscopic overlay in the presence of deformable lung motion. By driving registration via soft-tissue image gradients, the method avoided false local minima presented by bones and was robust to a wide range of motion magnitude.
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Affiliation(s)
- R Vijayan
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, United States of America
| | - N Sheth
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, United States of America
| | - L Mekki
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, United States of America
| | - A Lu
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, United States of America
| | - A Uneri
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, United States of America
| | - A Sisniega
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, United States of America
| | | | | | - S Vogt
- Siemens Healthineers, Erlangen, Germany
| | - J Thiboutot
- Division of Pulmonary and Critical Care Medicine, Johns Hopkins Medical Institution, Baltimore, MD, United States of America
| | - H Lee
- Division of Pulmonary and Critical Care Medicine, Johns Hopkins Medical Institution, Baltimore, MD, United States of America
| | - L Yarmus
- Division of Pulmonary and Critical Care Medicine, Johns Hopkins Medical Institution, Baltimore, MD, United States of America
| | - J H Siewerdsen
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, United States of America.,Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, United States of America
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Siewerdsen JH. Image quality models for 2D and 3D x-ray imaging systems: A perspective vignette. Med Phys 2022. [PMID: 36542332 DOI: 10.1002/mp.16051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Revised: 10/12/2022] [Accepted: 10/12/2022] [Indexed: 12/24/2022] Open
Abstract
Image quality models based on cascaded systems analysis and task-based imaging performance were an important aspect of the emergence of 2D and 3D digital x-ray systems over the last 25 years. This perspective vignette offers cursory review of such developments and personal insights that may not be obvious within previously published scientific literature. The vignette traces such models to the mid-1990s, when flat-panel x-ray detectors were emerging as a new base technology for digital radiography and benefited from the rigorous, objective characterization of imaging performance gained from such models. The connection of models for spatial resolution and noise to spatial-frequency-dependent descriptors of imaging task provided a useful framework for system optimization that helped to accelerate the development of new technologies to first clinical use. Extension of the models to new technologies and applications is also described, including dual-energy imaging, photon-counting detectors, phase contrast imaging, tomosynthesis, cone-beam CT, 3D image reconstruction, and image registration.
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Affiliation(s)
- Jeffrey H Siewerdsen
- Departments of Imaging Physics, Neurosurgery, and Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.,Director of Surgical Data Science, Institute for Data Science in Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
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Song X, Zhang X, Li J, Liang L, Yang Y, Li G, Bai S. [Automatic Delineation of Clinical Target Volume and Organ at Risk by Deep Learning for Prostate Cancer Adaptive Radiotherapy]. Zhongguo Yi Liao Qi Xie Za Zhi 2022; 46:691-695. [PMID: 36597401 DOI: 10.3969/j.issn.1671-7104.2022.06.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Adaptive radiotherapy can modify the treatment plan online based on the clinical target volume (CTV) and organ at risk (OAR) contours on the cone-beam CT (CBCT) before treatment, improving the accuracy of radiotherapy. However, manual delineation of CTV and OAR on CBCT is time-consuming. In this study, a deep neural network-based method based on U-Net was purposed. CBCT images and corresponding mask were used for model training and validation, showing superior performance in terms of the segmentation accuracy. The proposed method could be used in the clinic to support rapid CTV and OAR contouring for prostate adaptive radiotherapy.
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Affiliation(s)
- Xinyu Song
- Department of Radiotherapy, West China Hospital, Sichuan University, Chengdu, 610041
| | - Xiangyu Zhang
- Department of Radiotherapy, West China Hospital, Sichuan University, Chengdu, 610041
| | - Jing Li
- Department of Radiotherapy, West China Hospital, Sichuan University, Chengdu, 610041
| | - Lan Liang
- Department of Radiotherapy, West China Hospital, Sichuan University, Chengdu, 610041
| | - Yang Yang
- School of Physical Science and Technology, Wuhan University, Wuhan, 430072
| | - Guangjun Li
- Department of Radiotherapy, West China Hospital, Sichuan University, Chengdu, 610041
| | - Sen Bai
- Department of Radiotherapy, West China Hospital, Sichuan University, Chengdu, 610041
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Hrinivich WT, Chernavsky NE, Morcos M, Li T, Wu P, Wong J, Siewerdsen JH. Effect of subject motion and gantry rotation speed on image quality and dose delivery in CT-guided radiotherapy. Med Phys 2022; 49:6840-6855. [PMID: 35880711 DOI: 10.1002/mp.15877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Revised: 06/22/2022] [Accepted: 07/03/2022] [Indexed: 12/13/2022] Open
Abstract
PURPOSE To investigate the effects of subject motion and gantry rotation speed on computed tomography (CT) image quality over a range of image acquisition speeds for fan-beam (FB) and cone-beam (CB) CT scanners, and quantify the geometric and dosimetric errors introduced by FB and CB sampling in the context of adaptive radiotherapy. METHODS Images of motion phantoms were acquired using four CT scanners with gantry rotation speeds of 0.5 s/rotation (denoted FB-0.5), 1.9 s/rotation (FB-1.9), 16.6 s/rotation (CB-16.6), and 60.0 s/rotation (CB-60.0). A phantom presenting various tissue densities undergoing motion with 4-s period and ranging in amplitude from ±0.5 to ±10.0 mm was used to characterize motion artifacts (streaks), motion blur (edge-spread function, ESF), and geometric inaccuracy (excursion of insert centroids and distortion of known shape). An anthropomorphic abdomen phantom undergoing ±2.5-mm motion with 4-s period was used to simulate an adaptive radiotherapy workflow, and relative geometric and dosimetric errors were compared between scanners. RESULTS At ±2.5-mm motion, phantom measurements demonstrated mean ± SD ESF widths of 0.6 ± 0.0, 1.3 ± 0.4, 2.0 ± 1.1, and 2.9 ± 2.0 mm and geometric inaccuracy (excursion) of 2.7 ± 0.4, 4.1 ± 1.2, 2.6 ± 0.7, and 2.0 ± 0.5 mm for the FB-0.5, FB-1.9, CB-16.6, and CB-60.0 scanners, respectively. The results demonstrated nonmonotonic trends with scanner speed for FB and CB geometries. Geometric and dosimetric errors in adaptive radiotherapy plans were largest for the slowest (CB-60.0) scanner and similar for the three faster systems (CB-16.6, FB-1.9, and FB-0.5). CONCLUSIONS Clinically standard CB-60.0 demonstrates strong image quality degradation in the presence of subject motion, which is mitigated through faster CBCT or FBCT. Although motion blur is minimized for FB-0.5 and FB-1.9, such systems suffer from increased geometric distortion compared to CB-16.6. Each system reflects tradeoffs in image artifacts and geometric inaccuracies that affect treatment delivery/dosimetric error and should be considered in the design of next-generation CT-guided radiotherapy systems.
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Affiliation(s)
- William T Hrinivich
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University, Baltimore, Maryland, USA
| | - Nicole E Chernavsky
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland, USA
| | - Marc Morcos
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University, Baltimore, Maryland, USA
| | - Taoran Li
- Department of Radiation Oncology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Pengwei Wu
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland, USA
| | - John Wong
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University, Baltimore, Maryland, USA
| | - Jeffrey H Siewerdsen
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland, USA
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Biswal NC, Rodrigues DB, Yao W, Molitoris JK, Witek ME, Chen S. Evaluation of intrafraction couch shifts for proton treatment delivery in head-and-neck cancer patients: Toward optimal imaging frequency. J Appl Clin Med Phys 2022; 23:e13795. [PMID: 36239306 PMCID: PMC9797163 DOI: 10.1002/acm2.13795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 09/06/2022] [Accepted: 09/13/2022] [Indexed: 01/01/2023] Open
Abstract
PURPOSE Treatment planning for head-and-neck (H&N) cancer, in particular oropharynx, nasopharynx, and paranasal sinus cases, at our center requires noncoplanar proton beams due to the complexity of the anatomy and target location. Targeting accuracy for all beams is carefully evaluated by using image guidance before delivering proton beam therapy (PBT). In this study, we analyzed couch shifts to evaluate whether imaging is required before delivering each field with different couch angles. METHODS After the Institutional Review Board approval, a retrospective analysis was performed on data from 28 H&N patients treated with PBT. Each plan was made with two-to-three noncoplanar and two-to-three coplanar fields. Cone-beam computed tomography and orthogonal kilovoltage (kV) images were acquired for setup and before delivering each field, respectively. The Cartesian (longitudinal, vertical, and lateral) and angular (pitch and roll) shifts for each field were recorded from the treatment summary on the first two fractions and every subsequent fifth fraction. A net magnitude of the three-dimensional (3D) shift in Cartesian coordinates was calculated, and a 3D vector was created from the 6 degrees of freedom coordinates for transforming couch shifts in the system coordinate to the beam's-eye view. RESULTS A total of 3219 Cartesian and 2146 angular shift values were recorded for 28 patients. Of the Cartesian shifts, 2069 were zero (64.3%), and 1150 (35.7%) were nonzero (range, -7 to 11 mm). Of the angular shifts, 1034 (48.2%) were zero, and 1112 (51.8%) were nonzero (range, -3.0° to 3.2°). For 17 patients, the couch shifts increased toward the end of the treatment course. We also found that patients with higher body mass index (BMI) presented increased net couch shifts (p < 0.001). With BMI < 27, all overall net shift averages were <2 mm, and overall maximum net shifts were <6 mm. CONCLUSIONS These results confirm the need for orthogonal kV imaging before delivering each field of H&N PBT at our center, where a couch rotation is involved.
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Affiliation(s)
- Nrusingh C. Biswal
- Department of Radiation OncologyUniversity of Maryland School of MedicineBaltimoreMarylandUSA
| | - Dario B. Rodrigues
- Department of Radiation OncologyUniversity of Maryland School of MedicineBaltimoreMarylandUSA
| | - Weiguang Yao
- Department of Radiation OncologyUniversity of Maryland School of MedicineBaltimoreMarylandUSA
| | - Jason K. Molitoris
- Department of Radiation OncologyUniversity of Maryland School of MedicineBaltimoreMarylandUSA
| | - Matthew E. Witek
- Department of Radiation OncologyUniversity of Maryland School of MedicineBaltimoreMarylandUSA
| | - Shifeng Chen
- Department of Radiation OncologyUniversity of Maryland School of MedicineBaltimoreMarylandUSA
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Branco D, Mayadev J, Moore K, Ray X. Dosimetric and feasibility evaluation of a CBCT-based daily adaptive radiotherapy protocol for locally advanced cervical cancer. J Appl Clin Med Phys 2022; 24:e13783. [PMID: 36208134 PMCID: PMC9859994 DOI: 10.1002/acm2.13783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 07/13/2022] [Accepted: 08/23/2022] [Indexed: 01/26/2023] Open
Abstract
PURPOSE Evaluate a cone-beam computed tomography (CBCT)-based daily adaptive platform in cervical cancer for multiple endpoints: (1) physics contouring accuracy of daily CTVs, (2) CTV coverage with adapted plans and reduced PTV margins versus non-adapted plans with standard-of-care (SOC) margins, (3) dosimetric improvements to CTV and organs-at-risk (OARs), and (4) on-couch time. METHODS AND MATERIALS Using a Varian Ethos™ emulator and KV-CBCT scans, we simulated the doses 15 retrospective cervical cancer patients would have received with/without online adaptation for five fractions. We compared contours and doses from SOC plans (5-15 mm CTV-to-PTV margins) to adapted plans (3 mm margins). Auto-segmented CTVs and OARs were reviewed and edited by trained physicists. Physics-edited targets were evaluated by an oncologist. Time spent reviewing and editing auto-segmented structures was recorded. Metrics from the CTV (D99%), bowel (V45Gy, V40Gy), bladder (D50%), and rectum (D50%) were compared. RESULTS The physician approved the physics-edited CTVs for 55/75 fractions; 16/75 required reductions, and 4/75 required CTV expansions. CTVs were encapsulated by unadapted, SOC PTVs for 56/75 (72%) fractions-representative of current clinical practice. CTVs were completely covered by adapted 3 mm PTVs for 71/75 (94.6%) fractions. CTV D99% values for adapted plans were comparable to non-adapted SOC plans (average difference of -0.9%), while all OAR metrics improved with adaptation. Specifically, bowel V45Gy and V40Gy decreased on average by 87.6 and 109.4 cc, while bladder and rectum D50% decreased by 37.7% and 35.8%, respectively. The time required for contouring and calculating an adaptive plan for 65/75 fractions was less than 20 min (range: 1-29 min). CONCLUSIONS Improved dose metrics with daily adaption could translate to reduced toxicity while maintaining tumor control. Training physicists to perform contouring edits could minimize the time physicians are required at adaptive sessions improving clinical efficiency. All emulated adaptive sessions were completed within 30 min however extra time will be required for patient setup, image acquisition, and treatment delivery.
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Affiliation(s)
- Daniela Branco
- Department of Radiation Medicine and Applied SciencesUniversity of California San Diego3855 Health Sciences Drive, #0865La JollaCaliforniaUSA,California Protons Cancer Therapy CenterSan DiegoCaliforniaUnited States
| | - Jyoti Mayadev
- California Protons Cancer Therapy CenterSan DiegoCaliforniaUnited States
| | - Kevin Moore
- California Protons Cancer Therapy CenterSan DiegoCaliforniaUnited States
| | - Xenia Ray
- California Protons Cancer Therapy CenterSan DiegoCaliforniaUnited States
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Salapura V, Snoj Z, Leonardis L, Koritnik B, Kostadinova V. Cone-beam computed tomography guided nusinersen administrations in adult spinal muscular atrophy patients with challenging access: a single- center experience. Radiol Oncol 2022; 56:319-25. [PMID: 35962954 DOI: 10.2478/raon-2022-0033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Accepted: 06/12/2022] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND The challenging anatomic predispositions in adult patients with spinal muscular atrophy (SMA) preclude the conventional lumbar punctures. Consequently, an introduction of alternative method for intrathecal delivery of nusinersen is required. Cone-beam CT (CBCT) allows volumetric display of the area of interest, pre-procedural planning and real time needle guidance which results in accurate anatomic navigation. The aim of the study was to evaluate technical success, safety, and feasibility of CBCT lumbar intrathecal delivery of nusinersen in the adult SMA patients with challenging anatomical access. PATIENTS AND METHODS Thirty-eight adult SMA patients were treated in our institution. Patients with challenging access were selected by multidisciplinary board for image guided administration of nusinersen either due to implantation of the posterior fusion instrumentation, severe scoliosis defined as Cobb's angle > 40º or body mass index over 35. Technical success, radiation exposure and occurrence of adverse events were assessed. RESULTS Twenty patients were selected, and 108 CBCT-guided procedures were performed. Each patient underwent at least 4 administrations. Transforaminal approach was performed in 82% of patients. The technical success was 100%, with primary success of 93.5%. The median radiation effective dose of the administrations was 5 mSv, the mean value equalled 10 mSv. Only mild adverse events were reported in the study. CONCLUSIONS CBCT-guided lumbar intrathecal administrations of nusinersen in an adult SMA population with challenging access was feasible and safe image guided method.
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Balaguruswamy MM, Palanisamy S, Mohanasundaram PK, Madeswaran K. Cone Beam CT to Guide Transorbital Treatment of a Cavernous Sinus Dural Arteriovenous Fistula in a Patient with Middle Meningeal Artery Origin of the Ophthalmic Artery. Neurol India 2022; 70:1649-1651. [PMID: 36076675 DOI: 10.4103/0028-3886.355098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Transorbital puncture to embolize cavernous sinus (CS) dural arteriovenous fistulas (DAVF) is a useful strategy when conventional transvenous routes are inaccessible. We report a case of bilateral CS DAVF associated with bilateral middle meningeal artery (MMA) origin of ophthalmic arteries (OA) who had recently undergone transvenous coil embolization. She presented with persistent symptoms of conjunctival congestion and proptosis in the left eye. Angiogram revealed residual left CS DAVF with dilated SOV. Inferior petrosal sinus or facial vein access was not possible. Transorbital access of the SOV was planned. Cone-beam CT (CBCT) angiography was used to delineate the relationship between the variant OA and SOV and also to plan a safe trajectory. Using fluoroscopy guidance, the SOV was punctured and embolization was done using Onyx-18. CBCT is a valuable tool in planning and executing transorbital treatment of CS DAVF, especially in the setting of variant OA.
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Affiliation(s)
- Madan Mohan Balaguruswamy
- Department of Neurointerventional Radiology, Royal Care Super Specialty Hospital, Neelambur, Coimbatore, Tamil Nadu, India
| | - Sampathkumar Palanisamy
- Department of Neurointerventional Radiology, Royal Care Super Specialty Hospital, Neelambur, Coimbatore, Tamil Nadu, India
| | | | - Karuppannaswamy Madeswaran
- Department of Neurosurgery, Royal Care Super Specialty Hospital, Neelambur, Coimbatore, Tamil Nadu, India
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Huang H, Siewerdsen JH, Zbijewski W, Weiss CR, Unberath M, Ehtiati T, Sisniega A. Reference-free learning-based similarity metric for motion compensation in cone-beam CT. Phys Med Biol 2022; 67. [PMID: 35636391 DOI: 10.1088/1361-6560/ac749a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Accepted: 05/30/2022] [Indexed: 11/12/2022]
Abstract
Purpose. Patient motion artifacts present a prevalent challenge to image quality in interventional cone-beam CT (CBCT). We propose a novel reference-free similarity metric (DL-VIF) that leverages the capability of deep convolutional neural networks (CNN) to learn features associated with motion artifacts within realistic anatomical features. DL-VIF aims to address shortcomings of conventional metrics of motion-induced image quality degradation that favor characteristics associated with motion-free images, such as sharpness or piecewise constancy, but lack any awareness of the underlying anatomy, potentially promoting images depicting unrealistic image content. DL-VIF was integrated in an autofocus motion compensation framework to test its performance for motion estimation in interventional CBCT.Methods. DL-VIF is a reference-free surrogate for the previously reported visual image fidelity (VIF) metric, computed against a motion-free reference, generated using a CNN trained using simulated motion-corrupted and motion-free CBCT data. Relatively shallow (2-ResBlock) and deep (3-Resblock) CNN architectures were trained and tested to assess sensitivity to motion artifacts and generalizability to unseen anatomy and motion patterns. DL-VIF was integrated into an autofocus framework for rigid motion compensation in head/brain CBCT and assessed in simulation and cadaver studies in comparison to a conventional gradient entropy metric.Results. The 2-ResBlock architecture better reflected motion severity and extrapolated to unseen data, whereas 3-ResBlock was found more susceptible to overfitting, limiting its generalizability to unseen scenarios. DL-VIF outperformed gradient entropy in simulation studies yielding average multi-resolution structural similarity index (SSIM) improvement over uncompensated image of 0.068 and 0.034, respectively, referenced to motion-free images. DL-VIF was also more robust in motion compensation, evidenced by reduced variance in SSIM for various motion patterns (σDL-VIF = 0.008 versusσgradient entropy = 0.019). Similarly, in cadaver studies, DL-VIF demonstrated superior motion compensation compared to gradient entropy (an average SSIM improvement of 0.043 (5%) versus little improvement and even degradation in SSIM, respectively) and visually improved image quality even in severely motion-corrupted images.Conclusion: The studies demonstrated the feasibility of building reference-free similarity metrics for quantification of motion-induced image quality degradation and distortion of anatomical structures in CBCT. DL-VIF provides a reliable surrogate for motion severity, penalizes unrealistic distortions, and presents a valuable new objective function for autofocus motion compensation in CBCT.
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Affiliation(s)
- H Huang
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, United States of America
| | - J H Siewerdsen
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, United States of America.,Russell H. Morgan Department of Radiology, Johns Hopkins University, Baltimore, MD, United States of America.,Department of Computer Science, Johns Hopkins University, Baltimore, MD, United States of America
| | - W Zbijewski
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, United States of America
| | - C R Weiss
- Russell H. Morgan Department of Radiology, Johns Hopkins University, Baltimore, MD, United States of America
| | - M Unberath
- Department of Computer Science, Johns Hopkins University, Baltimore, MD, United States of America
| | - T Ehtiati
- Siemens Medical Solutions USA, Inc., Imaging & Therapy Systems, Hoffman Estates, IL, United States of America
| | - A Sisniega
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, United States of America
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Vasoglou G, Stefanidaki I, Apostolopoulos K, Fotakidou E, Vasoglou M. Accuracy of Mini-Implant Placement Using a Computer-Aided Designed Surgical Guide, with Information of Intraoral Scan and the Use of a Cone-Beam CT. Dent J (Basel) 2022; 10:104. [PMID: 35735647 DOI: 10.3390/dj10060104] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2022] [Revised: 05/24/2022] [Accepted: 06/06/2022] [Indexed: 12/19/2022] Open
Abstract
Background: The purpose of the study was to investigate the accuracy of mini-implant placement with the use of a computer designed surgical guide derived by intraoral scanning alongside Cone-Beam Computed Tomography (CBCT) or the use of a 2D radiograph. Methods: Thirty-five mini-implants (Aarhus® System: n = 20, Ø: 1.5 mm and AbsoAnchor®: n = 15, Ø: 1.3–1.4 mm) were placed in the maxilla and mandible of 15 orthodontic patients for anchorage purposes in cases where a CBCT was needed due to impacted teeth or for safety reasons. All were placed with the help of a computer designed surgical guide. One implant became loose and was excluded from the study. For 18 mini-implants (study group), CBCT and intraoral scanning were used for guide design, while for 16 (control group) only intraoral scanning and panoramic imaging information were used. Mini-implant position was recorded by angular and linear measurements on digital models created by combining Digital Imaging and Communications in Medicine (DICOM) and stereolithography (.stl) files. Accuracy in positioning was determined by comparing corresponding measurements for virtual and real positioned mini-implants on digital models before and after operation. The results were statistically analyzed with t-tests and the Mann-Whitney test. Results: No significant statistical differences were found for pre- and post-operational angular measurements in the study group, while significant statistical differences occurred on the same measurements for the control group (coronal angle 13.6° pre-op and 22.7° post-op, p-value = 0.002, axial angle 13.4° pre-op and 15.9° post-op, p-value = 0.034). Linear measurements pre- and post-operational for either group presented no significant statistical differences. Conclusions: A 3D designed and manufactured surgical guide with information concerning CBCT and intraoral scanning ensures accuracy on mini-implant placement while design of the guide without the use of a CBCT is less accurate, especially on inclination of the implant.
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Liu SZ, Herbst M, Weber T, Vogt S, Ritschl L, Kappler S, Siewerdsen JH, Zbijewski W. Dual-Energy Cone-Beam CT with Three-Material Decomposition for Bone Marrow Edema Imaging. Proc SPIE Int Soc Opt Eng 2022; 12304:123040Z. [PMID: 38223466 PMCID: PMC10788133 DOI: 10.1117/12.2646391] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2024]
Abstract
We investigate the feasibility of bone marrow edema (BME) detection using a kV-switching Dual-Energy (DE) Cone-Beam CT (CBCT) protocol. This task is challenging due to unmatched x-ray paths in the low-energy (LE) and high-energy (HE) spectral channels, CBCT non-idealities such as x-ray scatter, and narrow spectral separation between fat (bone marrow) and water (BME). We propose a comprehensive DE decomposition framework consisting of projection interpolation onto matching LE and HE view angles, fast Monte Carlo scatter correction with low number of tracked photons and Gaussian denoising, and two-stage three-material decompositions involving two-material (fat-Aluminium) Projection-Domain Decomposition (PDD) followed by image-domain three-material (fat-water-bone) base-change. Performance in BME detection was evaluated in simulations and experiments emulating a kV-switching CBCT wrist imaging protocol on a robotic x-ray system with 60 kV LE beam, 120 kV HE beam, and 0.5° angular shift between the LE and HE views. Cubic B-spline interpolation was found to be adequate to resample HE and LE projections of a wrist onto common view angles required by PDD. The DE decomposition maintained acceptable BME detection specificity (<0.2 mL erroneously detected BME volume compared to 0.85 mL true BME volume) over +/-10% range of scatter magnitude errors, as long as the scatter shape was estimated without major distortions. Physical test bench experiments demonstrated successful discrimination of ~20% change in fat concentrations in trabecular bone-mimicking solutions of varying water and fat content.
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Affiliation(s)
- Stephen Z. Liu
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD 21205
| | | | | | | | | | | | | | - Wojciech Zbijewski
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD 21205
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Nevalainen MT, Pitkänen MM, Saarakkala S. Diagnostic Performance of Ultrasonography for Evaluation of Osteoarthritis of Ankle Joint: Comparison With Radiography, Cone-Beam CT, and Symptoms. J Ultrasound Med 2022; 41:1139-1146. [PMID: 34378811 DOI: 10.1002/jum.15803] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 06/09/2021] [Accepted: 07/11/2021] [Indexed: 06/13/2023]
Abstract
OBJECTIVES To determine the diagnostic performance of ultrasonography (US) for evaluation of the ankle joint osteoarthritic (OA) changes. Cone-beam computed tomography (CT) was used as the gold standard and US performance was compared with conventional radiography (CR). As a secondary aim, associations between the imaging findings and ankle symptoms were assessed. METHODS US was performed to 51 patients with ankle OA. Every patient had prior ankle CR and underwent cone-beam CT during the same day as US examination. On US, effusion/synovitis, osteophytes, talar cartilage damage, and tenosynovitis were evaluated. Comparison to respective imaging findings on CR and cone-beam CT was then performed. Single radiologist blinded to other modalities assessed all the imaging studies. Symptoms questionnaire, the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), was available for 48 patients. RESULTS US detected effusion/synovitis of the talocrural joint with 45% sensitivity and 90% specificity. For the detection of anterior talocrural osteophytes, US sensitivity was 78% and specificity 79%. For the medial talocrural osteophytes, they were 39 and 83%, and for the lateral talocrural osteophytes 54 and 100%, respectively. Considering cartilage damage of the talus, US yielded a low sensitivity of 18% and high specificity of 97%. Overall, the performance of US was only moderate and comparable to CR. The imaging findings showed only weak associations with ankle symptoms. CONCLUSIONS The ability of US to detect ankle OA is only moderate. Interestingly, performance of CR also remained moderate. The associations between imaging findings and WOMAC score seem to be weak in ankle OA.
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Affiliation(s)
- Mika T Nevalainen
- Department of Diagnostic Radiology, Oulu University Hospital, Oulu
- Medical Research Center Oulu, University of Oulu, Oulu
- Research Unit of Medical Imaging, Physics and Technology, Faculty of Medicine, University of Oulu, Oulu
| | | | - Simo Saarakkala
- Department of Diagnostic Radiology, Oulu University Hospital, Oulu
- Medical Research Center Oulu, University of Oulu, Oulu
- Research Unit of Medical Imaging, Physics and Technology, Faculty of Medicine, University of Oulu, Oulu
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Sheikh K, Liu D, Li H, Acharya S, Ladra MM, Hrinivich WT. Dosimetric evaluation of cone-beam CT-based synthetic CTs in pediatric patients undergoing intensity-modulated proton therapy. J Appl Clin Med Phys 2022; 23:e13604. [PMID: 35413144 PMCID: PMC9194971 DOI: 10.1002/acm2.13604] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Revised: 03/10/2022] [Accepted: 03/21/2022] [Indexed: 11/07/2022] Open
Abstract
PURPOSE To evaluate dosimetric changes detected using synthetic computed tomography (sCT) derived from online cone-beam CTs (CBCT) in pediatric patients treated using intensity-modulated proton therapy (IMPT). METHODS Ten pediatric patients undergoing IMPT and aligned daily using proton gantry-mounted CBCT were identified for retrospective analysis with treated anatomical sites fully encompassed in the CBCT field of view. Dates were identified when the patient received both a CBCT and a quality assurance CT (qCT) for routine dosimetric evaluation. sCTs were generated based on a deformable registration between the initial plan CT (pCT) and CBCT. The clinical IMPT plans were re-computed on the same day qCT and sCT, and dosimetric changes due to tissue change or response from the initial plan were computed using each image. Linear regression analysis was performed to determine the correlation between dosimetric changes detected using the qCT and the sCT. Gamma analysis was also used to compare the dose distributions computed on the qCT and sCT. RESULTS The correlation coefficients (p-values) between qCTs and sCTs for changes detected in target coverage, overall maximum dose, and organ at risk dose were 0.97 (< .001), 0.84 (.002) and 0.91 (< .001), respectively. Mean ± SD gamma pass rates of the sCT-based dose compared to the qCT-based dose at 3%/3 mm, 3%/2 mm, and 2%/2 mm criteria were 96.5%±4.5%, 93.2%±6.3%, and 91.3%±7.8%, respectively. Pass rates tended to be lower for targets near lung. CONCLUSION While insufficient for re-planning, sCTs provide approximate dosimetry without administering additional imaging dose in pediatric patients undergoing IMPT. Dosimetric changes detected using sCTs are correlated with changes detected using clinically-standard qCTs; however, residual differences in dosimetry remain a limitation. Further improvements in sCT image quality may both improve online dosimetric evaluation and reduce imaging dose for pediatric patients by reducing the need for routine qCTs.
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Affiliation(s)
- Khadija Sheikh
- Department of Radiation Oncology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Dezhi Liu
- Department of Radiation Oncology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Heng Li
- Department of Radiation Oncology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Sahaja Acharya
- Department of Radiation Oncology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Matthew M Ladra
- Department of Radiation Oncology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - William T Hrinivich
- Department of Radiation Oncology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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Tseng HW, Karellas A, Vedantham S. Cone-beam breast CT using an offset detector: effect of detector offset and image reconstruction algorithm. Phys Med Biol 2022; 67. [PMID: 35316793 PMCID: PMC9045275 DOI: 10.1088/1361-6560/ac5fe1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 03/22/2022] [Indexed: 11/12/2022]
Abstract
Objective.A dedicated cone-beam breast computed tomography (BCT) using a high-resolution, low-noise detector operating in offset-detector geometry has been developed. This study investigates the effects of varying detector offsets and image reconstruction algorithms to determine the appropriate combination of detector offset and reconstruction algorithm.Approach.Projection datasets (300 projections in 360°) of 30 breasts containing calcified lesions that were acquired using a prototype cone-beam BCT system comprising a 40 × 30 cm flat-panel detector with 1024 × 768 detector pixels were reconstructed using Feldkamp-Davis-Kress (FDK) algorithm and served as the reference. The projection datasets were retrospectively truncated to emulate cone-beam datasets with sinograms of 768×768 and 640×768 detector pixels, corresponding to 5 cm and 7.5 cm lateral offsets, respectively. These datasets were reconstructed using the FDK algorithm with appropriate weights and an ASD-POCS-based Fast, total variation-Regularized, Iterative, Statistical reconstruction Technique (FRIST), resulting in a total of 4 offset-detector reconstructions (2 detector offsets × 2 reconstruction methods). Signal difference-to-noise ratio (SDNR), variance, and full-width at half-maximum (FWHM) of calcifications in two orthogonal directions were determined from all reconstructions. All quantitative measurements were performed on images in units of linear attenuation coefficient (1/cm).Results.The FWHM of calcifications did not differ (P > 0.262) among reconstruction algorithms and detector formats, implying comparable spatial resolution. For a chosen detector offset, the FRIST algorithm outperformed FDK in terms of variance and SDNR (P < 0.0001). For a given reconstruction method, the 5 cm offset provided better results.Significance.This study indicates the feasibility of using the compressed sensing-based, FRIST algorithm to reconstruct sinograms from offset-detectors. Among the reconstruction methods and detector offsets studied, FRIST reconstructions corresponding to a 30 cm × 30 cm with 5 cm lateral offset, achieved the best performance. A clinical prototype using such an offset geometry has been developed and installed for clinical trials.
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Affiliation(s)
- Hsin Wu Tseng
- Department of Medical Imaging, The University of Arizona, Tucson, AZ, United States of America
| | - Andrew Karellas
- Department of Medical Imaging, The University of Arizona, Tucson, AZ, United States of America
| | - Srinivasan Vedantham
- Department of Medical Imaging, The University of Arizona, Tucson, AZ, United States of America.,Department of Biomedical Engineering, The University of Arizona, Tucson, AZ, United States of America
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Sheth NM, Uneri A, Helm PA, Zbijewski W, Siewerdsen JH. Technical assessment of 2D and 3D imaging performance of an IGZO-based flat-panel X-ray detector. Med Phys 2022; 49:3053-3066. [PMID: 35363391 PMCID: PMC10153656 DOI: 10.1002/mp.15605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 03/09/2022] [Accepted: 03/09/2022] [Indexed: 11/08/2022] Open
Abstract
BACKGROUND Indirect detection flat-panel detectors (FPDs) consisting of hydrogenated amorphous silicon (a-Si:H) thin-film transistors (TFTs) are a prevalent technology for digital x-ray imaging. However, their performance is challenged in applications requiring low exposure levels, high spatial resolution, and high frame rate. Emerging FPD designs using metal oxide TFTs may offer potential performance improvements compared to FPDs based on a-Si:H TFTs. PURPOSE This work investigates the imaging performance of a new indium gallium zinc oxide (IGZO) TFT-based detector in 2D fluoroscopy and 3D cone-beam CT (CBCT). METHODS The new FPD consists of a sensor array combining IGZO TFTs with a-Si:H photodiodes and a 0.7-mm thick CsI:Tl scintillator. The FPD was implemented on an x-ray imaging bench with system geometry emulating intraoperative CBCT. A conventional FPD with a-Si:H TFTs and a 0.6-mm thick CsI:Tl scintillator was similarly implemented as a basis of comparison. 2D imaging performance was characterized in terms of electronic noise, sensitivity, linearity, lag, spatial resolution (modulation transfer function, MTF), image noise (noise-power spectrum, NPS), and detective quantum efficiency (DQE) with entrance air kerma (EAK) ranging from 0.3 to 1.2 μGy. 3D imaging performance was evaluated in terms of the 3D MTF and noise-equivalent quanta (NEQ), soft-tissue contrast-to-noise ratio (CNR), and image quality evident in anthropomorphic phantoms for a range of anatomical sites and dose, with weighted air kerma, K w ${K_w}$ , ranging from 0.8 to 4.9 mGy. RESULTS The 2D imaging performance of the IGZO-based FPD exhibited up to ∼1.7× lower electronic noise than the a-Si:H FPD at matched pixel pitch. Furthermore, the IGZO FPD exhibited ∼27% increase in mid-frequency DQE (1 mm-1 ) at matched pixel size and dose (EAK ≈ 1.0 μGy) and ∼11% increase after adjusting for differences in scintillator thickness. 2D spatial resolution was limited by the scintillator for each FPD. The IGZO-based FPD demonstrated improved 3D NEQ at all spatial frequencies in both head (≥25% increase for all dose levels) and body (≥10% increase for K w ${K_w}$ ≤2 mGy) imaging scenarios. These characteristics translated to improved low-contrast visualization in anthropomorphic phantoms, demonstrating ≥10% improvement in CNR and extension of the low-dose range for which the detector is input-quantum limited. CONCLUSION The IGZO-based FPD demonstrated improvements in electronic noise, image lag, and NEQ that translated to measurable improvements in 2D and 3D imaging performance compared to a conventional FPD based on a-Si:H TFTs. The improvements are most beneficial for 2D or 3D imaging scenarios involving low-dose and/or high-frame rate.
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Affiliation(s)
- Niral Milan Sheth
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland, USA
| | - Ali Uneri
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland, USA
| | | | - Wojciech Zbijewski
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland, USA
| | - Jeffrey H Siewerdsen
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland, USA
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Yuan N, Rao S, Chen Q, Sensoy L, Qi J, Rong Y. Head and neck synthetic CT generated from ultra-low-dose cone-beam CT following Image Gently Protocol using deep neural network. Med Phys 2022; 49:3263-3277. [PMID: 35229904 DOI: 10.1002/mp.15585] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 02/08/2022] [Accepted: 02/21/2022] [Indexed: 11/10/2022] Open
Abstract
PURPOSE Image guidance is used to improve accuracy of radiation therapy delivery but results in increased dose to patients. This is of particular concern in children who need be treated per Pediatric Image Gently Protocols due to long term risks from radiation exposure. The purpose of this study is to design a deep neural network (DNN) architecture and loss function for improving soft-tissue contrast and preserving small anatomical features in ultra-low-dose cone-beam CTs (CBCT) of head and neck cancer (HNC) imaging. METHODS A 2-D compound U-Net architecture (modified U-Net++) with different depths was proposed to enhance the network capability of capturing small-volume structures. A mask weighted loss function (Mask-Loss) was applied to enhance soft-tissue contrast. Fifty-five paired CBCT and CT images of HNC patients were retrospectively collected for network training and testing. The output enhanced CBCT images from the present study were evaluated with quantitative metrics including mean absolute error (MAE), signal-to-noise ratio (SNR), and structural similarity (SSIM), and compared with those from the previously proposed network architectures (U-Net and wide U-Net) using MAE loss functions. A visual assessment of ten selected structures in the enhanced CBCT images of each patient was performed to evaluate image quality improvement, blindly scored by an experienced radiation oncologist specialized in HN cancer. RESULTS All the enhanced CBCT images showed reduced artifactual distortion and image noise. U-Net++ outperformed the U-Net and wide U-Net in terms of MAE, contrast near structure boundaries, and small structures. The proposed Mask-Loss improved image contrast and accuracy of the soft-tissue regions. The enhanced CBCT images predicted by U-Net++ and Mask-Loss demonstrated improvement compared to the U-Net in terms of average MAE (52.41 vs. 42.85 HU), SNR (14.14 vs. 15.07 dB), and SSIM (0.84 vs. 0.87), respectively (p < 0.01, in all paired t-tests). The visual assessment showed that the proposed U-Net++ and Mask-Loss significantly improved original CBCTs (p < 0.01), compared to the U-Net and MAE loss. CONCLUSIONS The proposed network architecture and loss function effectively improved image quality in soft-tissue contrast, organ boundary, and small structures preservation for ultra-low-dose CBCT following Image Gently Protocol. This method has potential to provide sufficient anatomical representation on the enhanced CBCT images for accurate treatment delivery and potentially fast online-adaptive re-planning for HN cancer patients. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Nimu Yuan
- Department of Biomedical Engineering, University of California, Davis, CA, 95616, United States
| | - Shyam Rao
- Department of Radiation Oncology, University of California Davis Medical Center, Sacramento, CA, 95817, United States
| | - Quan Chen
- Department of Radiation Oncology, University of Kentucky, Lexington, KY, 40536, United States
| | - Levent Sensoy
- Department of Radiation Oncology, University of California Davis Medical Center, Sacramento, CA, 95817, United States
| | - Jinyi Qi
- Department of Biomedical Engineering, University of California, Davis, CA, 95616, United States
| | - Yi Rong
- Department of Radiation Oncology, University of California Davis Medical Center, Sacramento, CA, 95817, United States.,Department of Radiation Oncology, Mayo Clinic Arizona, Phoenix, AZ, 85054, United States
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Chai ZK, Mao L, Chen H, Sun TG, Shen XM, Liu J, Sun ZJ. Improved Diagnostic Accuracy of Ameloblastoma and Odontogenic Keratocyst on Cone-Beam CT by Artificial Intelligence. Front Oncol 2022; 11:793417. [PMID: 35155194 PMCID: PMC8828501 DOI: 10.3389/fonc.2021.793417] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Accepted: 12/30/2021] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVE The purpose of this study was to utilize a convolutional neural network (CNN) to make preoperative differential diagnoses between ameloblastoma (AME) and odontogenic keratocyst (OKC) on cone-beam CT (CBCT). METHODS The CBCT images of 178 AMEs and 172 OKCs were retrospectively retrieved from the Hospital of Stomatology, Wuhan University. The datasets were randomly split into a training dataset of 272 cases and a testing dataset of 78 cases. Slices comprising lesions were retained and then cropped to suitable patches for training. The Inception v3 deep learning algorithm was utilized, and its diagnostic performance was compared with that of oral and maxillofacial surgeons. RESULTS The sensitivity, specificity, accuracy, and F1 score were 87.2%, 82.1%, 84.6%, and 85.0%, respectively. Furthermore, the average scores of the same indexes for 7 senior oral and maxillofacial surgeons were 60.0%, 71.4%, 65.7%, and 63.6%, respectively, and those of 30 junior oral and maxillofacial surgeons were 63.9%, 53.2%, 58.5%, and 60.7%, respectively. CONCLUSION The deep learning model was able to differentiate these two lesions with better diagnostic accuracy than clinical surgeons. The results indicate that the CNN may provide assistance for clinical diagnosis, especially for inexperienced surgeons.
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Affiliation(s)
- Zi-Kang Chai
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine, Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Liang Mao
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine, Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China.,Department of Oral Maxillofacial-Head Neck Oncology, School and Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Hua Chen
- Institute of Artificial Intelligence, School of Computer Science, Wuhan University, Wuhan, China
| | - Ting-Guan Sun
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine, Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Xue-Meng Shen
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine, Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Juan Liu
- Institute of Artificial Intelligence, School of Computer Science, Wuhan University, Wuhan, China
| | - Zhi-Jun Sun
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine, Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China.,Department of Oral Maxillofacial-Head Neck Oncology, School and Hospital of Stomatology, Wuhan University, Wuhan, China
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49
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Liu SZ, Zhao C, Herbst M, Weber T, Vogt S, Ritschl L, Kappler S, Siewerdsen JH, Zbijewski W. Feasibility of Dual-Energy Cone-Beam CT of Bone Marrow Edema Using Dual-Layer Flat Panel Detectors. Proc SPIE Int Soc Opt Eng 2022; 12031:120311J. [PMID: 38223908 PMCID: PMC10788135 DOI: 10.1117/12.2613211] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2024]
Abstract
Purpose We investigated the feasibility of detection and quantification of bone marrow edema (BME) using dual-energy (DE) Cone-Beam CT (CBCT) with a dual-layer flat panel detector (FPD) and three-material decomposition. Methods A realistic CBCT system simulator was applied to study the impact of detector quantization, scatter, and spectral calibration errors on the accuracy of fat-water-bone decompositions of dual-layer projections. The CBCT system featured 975 mm source-axis distance, 1,362 mm source-detector distance and a 430 × 430 mm2 dual-layer FPD (top layer: 0.20 mm CsI:Tl, bottom layer: 0.55 mm CsI:Tl; a 1 mm Cu filter between the layers to improve spectral separation). Tube settings were 120 kV (+2 mm Al, +0.2 mm Cu) and 10 mAs per exposure. The digital phantom consisted of a 160 mm water cylinder with inserts containing mixtures of water (volume fraction ranging 0.18 to 0.46) - fat (0.5 to 0.7) - Ca (0.04 to 0.12); decreasing fractions of fat indicated increasing degrees of BME. A two-stage three-material DE decomposition was applied to DE CBCT projections: first, projection-domain decomposition (PDD) into fat-aluminum basis, followed by CBCT reconstruction of intermediate base images, followed by image-domain change of basis into fat, water and bone. Sensitivity to scatter was evaluated by i) adjusting source collimation (12 to 400 mm width) and ii) subtracting various fractions of the true scatter from the projections at 400 mm collimation. The impact of spectral calibration was studied by shifting the effective beam energy (± 2 keV) when creating the PDD lookup table. We further simulated a realistic BME imaging framework, where the scatter was estimated using a fast Monte Carlo (MC) simulation from a preliminary decomposition of the object; the object was a realistic wrist phantom with an 0.85 mL BME stimulus in the radius. Results The decomposition is sensitive to scatter: approx. <20 mm collimation width or <10% error of scatter correction in a full field-of-view setting is needed to resolve BME. A mismatch in PDD decomposition calibration of ± 1 keV results in ~25% error in fat fraction estimates. In the wrist phantom study with MC scatter corrections, we were able to achieve ~0.79 mL true positive and ~0.06 mL false positive BME detection (compared to 0.85 mL true BME volume). Conclusions Detection of BME using DE CBCT with dual-layer FPD is feasible, but requires scatter mitigation, accurate scatter estimation, and robust spectral calibration.
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Affiliation(s)
- Stephen Z. Liu
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD 21205
| | - Chumin Zhao
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD 21205
| | | | | | | | | | | | | | - Wojciech Zbijewski
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD 21205
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50
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Sisniega A, Lu A, Huang H, Zbijewski W, Unberath M, Siewerdsen JH, Weiss CR. Targeted Deformable Motion Compensation for Vascular Interventional Cone-Beam CT Imaging. Proc SPIE Int Soc Opt Eng 2022; 12031:120311H. [PMID: 36381563 PMCID: PMC9654751 DOI: 10.1117/12.2613232] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Purpose Cone-beam CT has become commonplace for 3D guidance in interventional radiology (IR), especially for vascular procedures in which identification of small vascular structures is crucial. However, its long image acquisition time poses a limit to image quality due to soft-tissue deformable motion that hampers visibility of small vessels. Autofocus motion compensation has shown promising potential for soft-tissue deformable motion compensation, but it lacks specific target to the imaging task. This work presents an approach for deformable motion compensation targeted at imaging of vascular structures. Methods The proposed method consists on a two-stage framework for: i) identification of contrast-enhanced blood vessels in 2D projection data and delineation of an approximate region covering the vascular target in the volume space, and, ii) a novel autofocus approach including a metric designed to promote the presence of vascular structures acting solely in the region of interest. The vesselness of the image is quantified via evaluation of the properties of the 3D image Hessian, yielding a vesselness filter that gives larger values to voxels candidate to be part of a tubular structure. A cost metric is designed to promote large vesselness values and spatial sparsity, as expected in regions of fine vascularity. A targeted autofocus method was designed by combining the presented metric with a conventional autofocus term acting outside of the region of interest. The resulting method was evaluated on simulated data including synthetic vascularity merged with real anatomical features obtained from MDCT data. Further evaluation was obtained in two clinical datasets obtained during TACE procedures with a robotic C-arm (Artis Zeego, Siemens Healthineers). Results The targeted vascular autofocus effectively restored the shape and contrast of the contrast-enhanced vascularity in the simulation cases, resulting in improved visibility and reduced artifacts. Segmentations performed with a single threshold value on the target vascular regions yielded a net increase of up to 42% in DICE coefficient computed against the static reference. Motion compensation in clinical datasets resulted in improved visibility of vascular structures, observed in maximum intensity projections of the contrast-enhanced liver vessel tree. Conclusion Targeted motion compensation for vascular imaging showed promising performance for increased identification of small vascular structures in presence of motion. The development of autofocus metrics and methods tailored to vascular imaging opens the way for reliable compensation of deformable motion while preserving the integrity of anatomical structures in the image.
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Affiliation(s)
- A Sisniega
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD USA
| | - A Lu
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD USA
| | - H Huang
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD USA
| | - W Zbijewski
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD USA
| | - M Unberath
- Department of Computer Science, Johns Hopkins University, Baltimore, MD USA
| | - J H Siewerdsen
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD USA
- Russell H. Morgan Department of Radiology, Johns Hopkins University, Baltimore, MD USA
| | - C R Weiss
- Russell H. Morgan Department of Radiology, Johns Hopkins University, Baltimore, MD USA
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