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Poimala J, Cox B, Hauptmann A. Compensating unknown speed of sound in learned fast 3D limited-view photoacoustic tomography. Photoacoustics 2024; 37:100597. [PMID: 38425677 PMCID: PMC10901832 DOI: 10.1016/j.pacs.2024.100597] [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] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 08/15/2023] [Accepted: 02/16/2024] [Indexed: 03/02/2024]
Abstract
Real-time applications in three-dimensional photoacoustic tomography from planar sensors rely on fast reconstruction algorithms that assume the speed of sound (SoS) in the tissue is homogeneous. Moreover, the reconstruction quality depends on the correct choice for the constant SoS. In this study, we discuss the possibility of ameliorating the problem of unknown or heterogeneous SoS distributions by using learned reconstruction methods. This can be done by modelling the uncertainties in the training data. In addition, a correction term can be included in the learned reconstruction method. We investigate the influence of both and while a learned correction component can improve reconstruction quality further, we show that a careful choice of uncertainties in the training data is the primary factor to overcome unknown SoS. We support our findings with simulated and in vivo measurements in 3D.
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Affiliation(s)
- Jenni Poimala
- Research Unit of Mathematical Sciences, University of Oulu, Finland
| | - Ben Cox
- Department of Medical Physics and Biomedical Engineering, University College London, UK
| | - Andreas Hauptmann
- Research Unit of Mathematical Sciences, University of Oulu, Finland
- Department of Computer Science, University College London, UK
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2
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Huang Y, Zhang X, Hu Y, Johnston AR, Jones CK, Zbijewski WB, Siewerdsen JH, Helm PA, Witham TF, Uneri A. Deformable registration of preoperative MR and intraoperative long-length tomosynthesis images for guidance of spine surgery via image synthesis. Comput Med Imaging Graph 2024; 114:102365. [PMID: 38471330 DOI: 10.1016/j.compmedimag.2024.102365] [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: 10/04/2023] [Revised: 01/31/2024] [Accepted: 02/22/2024] [Indexed: 03/14/2024]
Abstract
PURPOSE Improved integration and use of preoperative imaging during surgery hold significant potential for enhancing treatment planning and instrument guidance through surgical navigation. Despite its prevalent use in diagnostic settings, MR imaging is rarely used for navigation in spine surgery. This study aims to leverage MR imaging for intraoperative visualization of spine anatomy, particularly in cases where CT imaging is unavailable or when minimizing radiation exposure is essential, such as in pediatric surgery. METHODS This work presents a method for deformable 3D-2D registration of preoperative MR images with a novel intraoperative long-length tomosynthesis imaging modality (viz., Long-Film [LF]). A conditional generative adversarial network is used to translate MR images to an intermediate bone image suitable for registration, followed by a model-based 3D-2D registration algorithm to deformably map the synthesized images to LF images. The algorithm's performance was evaluated on cadaveric specimens with implanted markers and controlled deformation, and in clinical images of patients undergoing spine surgery as part of a large-scale clinical study on LF imaging. RESULTS The proposed method yielded a median 2D projection distance error of 2.0 mm (interquartile range [IQR]: 1.1-3.3 mm) and a 3D target registration error of 1.5 mm (IQR: 0.8-2.1 mm) in cadaver studies. Notably, the multi-scale approach exhibited significantly higher accuracy compared to rigid solutions and effectively managed the challenges posed by piecewise rigid spine deformation. The robustness and consistency of the method were evaluated on clinical images, yielding no outliers on vertebrae without surgical instrumentation and 3% outliers on vertebrae with instrumentation. CONCLUSIONS This work constitutes the first reported approach for deformable MR to LF registration based on deep image synthesis. The proposed framework provides access to the preoperative annotations and planning information during surgery and enables surgical navigation within the context of MR images and/or dual-plane LF images.
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Affiliation(s)
- Yixuan Huang
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, United States
| | - Xiaoxuan Zhang
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, United States
| | - Yicheng Hu
- Department of Computer Science, Johns Hopkins University, Baltimore, MD, United States
| | - Ashley R Johnston
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, United States
| | - Craig K Jones
- Department of Computer Science, Johns Hopkins University, Baltimore, MD, United States
| | - Wojciech B Zbijewski
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, United States
| | - Jeffrey H Siewerdsen
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, United States; Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, United States
| | | | - Timothy F Witham
- Department of Neurosurgery, Johns Hopkins Medicine, Baltimore, MD, United States
| | - Ali Uneri
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, United States.
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Franciosini G, Carlotti D, Cattani F, De Gregorio A, De Liso V, De Rosa F, Di Francesco M, Di Martino F, Felici G, Pensavalle JH, Leonardi MC, Marafini M, Muscato A, Paiar F, Patera V, Poortmans P, Sciubba A, Schiavi A, Toppi M, Traini G, Trigilio A, Sarti A. IOeRT conventional and FLASH treatment planning system implementation exploiting fast GPU Monte Carlo: The case of breast cancer. Phys Med 2024; 121:103346. [PMID: 38608421 DOI: 10.1016/j.ejmp.2024.103346] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Revised: 03/13/2024] [Accepted: 04/01/2024] [Indexed: 04/14/2024] Open
Abstract
Partial breast irradiation for the treatment of early-stage breast cancer patients can be performed by means of Intra Operative electron Radiation Therapy (IOeRT). One of the main limitations of this technique is the absence of a treatment planning system (TPS) that could greatly help in ensuring a proper coverage of the target volume during irradiation. An IOeRT TPS has been developed using a fast Monte Carlo (MC) and an ultrasound imaging system to provide the best irradiation strategy (electron beam energy, applicator position and bevel angle) and to facilitate the optimisation of dose prescription and delivery to the target volume while maximising the organs at risk sparing. The study has been performed in silico, exploiting MC simulations of a breast cancer treatment. Ultrasound-based input has been used to compute the absorbed dose maps in different irradiation strategies and a quantitative comparison between the different options was carried out using Dose Volume Histograms. The system was capable of exploring different beam energies and applicator positions in few minutes, identifying the best strategy with an overall computation time that was found to be completely compatible with clinical implementation. The systematic uncertainty related to tissue deformation during treatment delivery with respect to imaging acquisition was taken into account. The potential and feasibility of a GPU based full MC TPS implementation of IOeRT breast cancer treatments has been demonstrated in-silico. This long awaited tool will greatly improve the treatment safety and efficacy, overcoming the limits identified within the clinical trials carried out so far.
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Affiliation(s)
- G Franciosini
- Sapienza, University of Rome, Department of Scienze di Base e Applicate all'Ingegneria, Rome, Italy; National Institute of Nuclear Physics, INFN, Section of Rome I, Rome, Italy
| | - D Carlotti
- Operative Research Unit of Radiation Oncology, Fondazione Policlinico Universitatio Campus-Bio Medico, Rome, Italy
| | - F Cattani
- Unit of Medical Physics, European Institute of Oncology IRCCS, Milan, Italy
| | - A De Gregorio
- National Institute of Nuclear Physics, INFN, Section of Rome I, Rome, Italy; Sapienza, University of Rome, Department of Physics, Rome, Italy
| | - V De Liso
- S.I.T. Sordina IORT Technologies S.p.A, Aprilia, Italy
| | - F De Rosa
- Sapienza, University of Rome, Department of Scienze di Base e Applicate all'Ingegneria, Rome, Italy
| | | | - F Di Martino
- Centro Pisano Multidisciplinare sulla Ricerca e Implementazione Clinica della Flash Radiotherapy (CPFR), Pisa, Italy; University of Pisa, Department of Physics, Pisa, Italy; Azienda Ospedaliero Universitaria Pisa (AOUP), Fisica Sanitaria, Pisa, Italy; National Institute of Nuclear Physics, INFN, Section of Pisa, Pisa, Italy
| | - G Felici
- S.I.T. Sordina IORT Technologies S.p.A, Aprilia, Italy
| | - J Harold Pensavalle
- S.I.T. Sordina IORT Technologies S.p.A, Aprilia, Italy; Centro Pisano Multidisciplinare sulla Ricerca e Implementazione Clinica della Flash Radiotherapy (CPFR), Pisa, Italy; National Institute of Nuclear Physics, INFN, Section of Pisa, Pisa, Italy
| | - M C Leonardi
- Division of Radiation Oncology, European Institute of Oncology IRCCS, Milan, Italy
| | - M Marafini
- National Institute of Nuclear Physics, INFN, Section of Rome I, Rome, Italy; Museo Storico della Fisica e Centro Studi e Ricerche "E. Fermi", Rome, Italy
| | - A Muscato
- National Institute of Nuclear Physics, INFN, Section of Rome I, Rome, Italy; Specialty School of Medical Physics, La Sapienza University of Rome, Rome, Italy
| | - F Paiar
- Centro Pisano Multidisciplinare sulla Ricerca e Implementazione Clinica della Flash Radiotherapy (CPFR), Pisa, Italy; Azienda Ospedaliero Universitaria Pisa (AOUP), Fisica Sanitaria, Pisa, Italy
| | - V Patera
- Sapienza, University of Rome, Department of Scienze di Base e Applicate all'Ingegneria, Rome, Italy; National Institute of Nuclear Physics, INFN, Section of Rome I, Rome, Italy
| | - P Poortmans
- Department of Radiation Oncology, Iridium Netwerk, Antwerp, Belgium; University of Antwerp, Faculty of Medicine and Health Sciences, Antwerp, Belgium
| | - A Sciubba
- Sapienza, University of Rome, Department of Scienze di Base e Applicate all'Ingegneria, Rome, Italy; National Institute of Nuclear Physics, INFN, Frascati National Laboratories (LNF), Rome, Italy
| | - A Schiavi
- Sapienza, University of Rome, Department of Scienze di Base e Applicate all'Ingegneria, Rome, Italy; National Institute of Nuclear Physics, INFN, Section of Rome I, Rome, Italy
| | - M Toppi
- Sapienza, University of Rome, Department of Scienze di Base e Applicate all'Ingegneria, Rome, Italy; National Institute of Nuclear Physics, INFN, Section of Rome I, Rome, Italy
| | - G Traini
- National Institute of Nuclear Physics, INFN, Section of Rome I, Rome, Italy
| | - A Trigilio
- Sapienza, University of Rome, Department of Physics, Rome, Italy; National Institute of Nuclear Physics, INFN, Frascati National Laboratories (LNF), Rome, Italy
| | - A Sarti
- Sapienza, University of Rome, Department of Scienze di Base e Applicate all'Ingegneria, Rome, Italy; National Institute of Nuclear Physics, INFN, Section of Rome I, Rome, Italy.
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Issa ASM, Scheins J, Tellmann L, Brambilla CR, Lohmann P, Rota-Kops E, Herzog H, Neuner I, Shah NJ, Lerche C. Impact of improved dead time correction on the quantification accuracy of a dedicated BrainPET scanner. PLoS One 2024; 19:e0296357. [PMID: 38578749 PMCID: PMC10997125 DOI: 10.1371/journal.pone.0296357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Accepted: 12/11/2023] [Indexed: 04/07/2024] Open
Abstract
OBJECTIVE Quantitative values derived from PET brain images are of high interest for neuroscientific applications. Insufficient DT correction (DTC) can lead to a systematic bias of the output parameters obtained by a detailed analysis of the time activity curves (TACs). The DTC method currently used for the Siemens 3T MR BrainPET insert is global, i.e., differences in DT losses between detector blocks are not considered, leading to inaccurate DTC and, consequently, to inaccurate measurements masked by a bias. However, following careful evaluation with phantom measurements, a new block-pairwise DTC method has demonstrated a higher degree of accuracy compared to the global DTC method. APPROACH Differences between the global and the block-pairwise DTC method were studied in this work by applying several radioactive tracers. We evaluated the impact on [11C]ABP688, O-(2-[18F]fluoroethyl)-L-tyrosine (FET), and [15O]H2O TACs. RESULTS For [11C]ABP688, a relevant bias of between -0.0034 and -0.0053 ml/ (cm3 • min) was found in all studied brain regions for the volume of distribution (VT) when using the current global DTC method. For [18F]FET-PET, differences of up to 10% were observed in the tumor-to-brain ratio (TBRmax), these differences depend on the radial distance of the maximum from the PET isocenter. For [15O]H2O, differences between +4% and -7% were observed in the GM region. Average biases of -4.58%, -3.2%, and -1.2% for the regional cerebral blood flow (CBF (K1)), the rate constant k2, and the volume of distribution VT were observed, respectively. Conversely, in the white matter region, average biases of -4.9%, -7.0%, and 3.8% were observed for CBF (K1), k2, and VT, respectively. CONCLUSION The bias introduced by the global DTC method leads to an overestimation in the studied quantitative parameters for all applications compared to the block-pairwise method. SIGNIFICANCE The observed differences between the two DTC methods are particularly relevant for research applications in neuroscientific studies as they affect the accuracy of quantitative Brain PET images.
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Affiliation(s)
- Ahlam Said Mohamad Issa
- Institute of Neuroscience and Medicine 4, INM-4, Forschungszentrum Jülich, Jülich, Germany
- JARA, BRAIN, Translational Medicine, Aachen, Germany
- Department of Neurology, Faculty of Medicine, RWTH Aachen University, Aachen, Germany
| | - Jürgen Scheins
- Institute of Neuroscience and Medicine 4, INM-4, Forschungszentrum Jülich, Jülich, Germany
| | - Lutz Tellmann
- Institute of Neuroscience and Medicine 4, INM-4, Forschungszentrum Jülich, Jülich, Germany
| | | | - Philipp Lohmann
- Institute of Neuroscience and Medicine 4, INM-4, Forschungszentrum Jülich, Jülich, Germany
| | - Elena Rota-Kops
- Institute of Neuroscience and Medicine 4, INM-4, Forschungszentrum Jülich, Jülich, Germany
| | - Hans Herzog
- Institute of Neuroscience and Medicine 4, INM-4, Forschungszentrum Jülich, Jülich, Germany
| | - Irene Neuner
- Institute of Neuroscience and Medicine 4, INM-4, Forschungszentrum Jülich, Jülich, Germany
- JARA, BRAIN, Translational Medicine, Aachen, Germany
- Department of Psychiatry, Psychotherapy and Psychosomatics, RWTH Aachen University, Aachen, Germany
| | - N. Jon Shah
- Institute of Neuroscience and Medicine 4, INM-4, Forschungszentrum Jülich, Jülich, Germany
- JARA, BRAIN, Translational Medicine, Aachen, Germany
- Department of Neurology, Faculty of Medicine, RWTH Aachen University, Aachen, Germany
- Institute of Neuroscience and Medicine 11, INM-11, JARA, Forschungszentrum Jülich, Jülich, Germany
| | - Christoph Lerche
- Institute of Neuroscience and Medicine 4, INM-4, Forschungszentrum Jülich, Jülich, Germany
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Jia Y, Zhang S, Zhang X, Long H, Xu C, Bai Y, Cheng Y, Wu D, Deng M, Qiu CW, Liu X. Compact meta-differentiator for achieving isotropically high-contrast ultrasonic imaging. Nat Commun 2024; 15:2934. [PMID: 38575561 PMCID: PMC10995138 DOI: 10.1038/s41467-024-47303-7] [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: 07/27/2023] [Accepted: 03/25/2024] [Indexed: 04/06/2024] Open
Abstract
Ultrasonic imaging is crucial in the fields of biomedical engineering for its deep penetration capabilities and non-ionizing nature. However, traditional techniques heavily rely on impedance differences within objects, resulting in poor contrast when imaging acoustically transparent targets. Here, we propose a compact spatial differentiator for underwater isotropic edge-enhanced imaging, which enhances the imaging contrast without the need for contrast agents or external physical fields. This design incorporates an amplitude meta-grating for linear transmission along the radial direction, combined with a phase meta-grating that utilizes focus and spiral phases with a first-order topological charge. Through theoretical analysis, numerical simulations, and experimental validation, we substantiate the effectiveness of our technique in distinguishing amplitude objects with isotropic edge enhancements. Importantly, this method also enables the accurate detection of both phase objects and artificial biological models. This breakthrough creates new opportunities for applications in medical diagnosis and nondestructive testing.
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Affiliation(s)
- Yurou Jia
- Department of Physics, MOE Key Laboratory of Modern Acoustics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore, 117583, Singapore
| | - Suying Zhang
- Department of Physics, MOE Key Laboratory of Modern Acoustics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Xuan Zhang
- Department of Physics, MOE Key Laboratory of Modern Acoustics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Houyou Long
- Department of Physics, MOE Key Laboratory of Modern Acoustics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China.
| | - Caibin Xu
- College of Aerospace Engineering, Chongqing University, Chongqing, 400044, China
| | - Yechao Bai
- School of Electronic Science and Engineering, Nanjing University, Nanjing, 210023, China
| | - Ying Cheng
- Department of Physics, MOE Key Laboratory of Modern Acoustics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China.
- State Key Laboratory of Acoustics, Institute of Acoustics, Chinese Academy of Sciences, Beijing, 100190, China.
| | - Dajian Wu
- Jiangsu Key Lab on Opto-Electronic Technology, School of Physics and Technology, Nanjing Normal University, Nanjing, 210023, China
| | - Mingxi Deng
- College of Aerospace Engineering, Chongqing University, Chongqing, 400044, China
| | - Cheng-Wei Qiu
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore, 117583, Singapore
| | - Xiaojun Liu
- Department of Physics, MOE Key Laboratory of Modern Acoustics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China.
- State Key Laboratory of Acoustics, Institute of Acoustics, Chinese Academy of Sciences, Beijing, 100190, China.
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Lang Y, Jiang Z, Sun L, Xiang L, Ren L. Hybrid-supervised deep learning for domain transfer 3D protoacoustic image reconstruction. Phys Med Biol 2024; 69:085007. [PMID: 38471184 DOI: 10.1088/1361-6560/ad3327] [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: 07/21/2023] [Accepted: 03/12/2024] [Indexed: 03/14/2024]
Abstract
Objective. Protoacoustic imaging showed great promise in providing real-time 3D dose verification of proton therapy. However, the limited acquisition angle in protoacoustic imaging induces severe artifacts, which impairs its accuracy for dose verification. In this study, we developed a hybrid-supervised deep learning method for protoacoustic imaging to address the limited view issue.Approach. We proposed a Recon-Enhance two-stage deep learning method. In the Recon-stage, a transformer-based network was developed to reconstruct initial pressure maps from raw acoustic signals. The network is trained in a hybrid-supervised approach, where it is first trained using supervision by the iteratively reconstructed pressure map and then fine-tuned using transfer learning and self-supervision based on the data fidelity constraint. In the enhance-stage, a 3D U-net is applied to further enhance the image quality with supervision from the ground truth pressure map. The final protoacoustic images are then converted to dose for proton verification.Main results. The results evaluated on a dataset of 126 prostate cancer patients achieved an average root mean squared errors (RMSE) of 0.0292, and an average structural similarity index measure (SSIM) of 0.9618, out-performing related start-of-the-art methods. Qualitative results also demonstrated that our approach addressed the limit-view issue with more details reconstructed. Dose verification achieved an average RMSE of 0.018, and an average SSIM of 0.9891. Gamma index evaluation demonstrated a high agreement (94.7% and 95.7% for 1%/3 mm and 1%/5 mm) between the predicted and the ground truth dose maps. Notably, the processing time was reduced to 6 s, demonstrating its feasibility for online 3D dose verification for prostate proton therapy.Significance. Our study achieved start-of-the-art performance in the challenging task of direct reconstruction from radiofrequency signals, demonstrating the great promise of PA imaging as a highly efficient and accurate tool forinvivo3D proton dose verification to minimize the range uncertainties of proton therapy to improve its precision and outcomes.
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Affiliation(s)
- Yankun Lang
- Department of Radiation Oncology Physics, University of Maryland, Baltimore, Baltimore, MD 21201, United States of America
| | - Zhuoran Jiang
- Department of Radiation Oncology, Duke University, Durham, NC 27710, United States of America
| | - Leshan Sun
- Department of Biomedical Engineering and Radiology, University of California, Irvine, Irnive, CA, 92617, United States of America
| | - Liangzhong Xiang
- Department of Biomedical Engineering and Radiology, University of California, Irvine, Irnive, CA, 92617, United States of America
| | - Lei Ren
- Department of Radiation Oncology Physics, University of Maryland, Baltimore, Baltimore, MD 21201, United States of America
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Yu Y, Feng T, Qiu H, Gu Y, Chen Q, Zuo C, Ma H. Simultaneous photoacoustic and ultrasound imaging: A review. Ultrasonics 2024; 139:107277. [PMID: 38460216 DOI: 10.1016/j.ultras.2024.107277] [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] [Subscribe] [Scholar Register] [Received: 09/10/2023] [Revised: 01/09/2024] [Accepted: 02/26/2024] [Indexed: 03/11/2024]
Abstract
Photoacoustic imaging (PAI) is an emerging biomedical imaging technique that combines the advantages of optical and ultrasound imaging, enabling the generation of images with both optical resolution and acoustic penetration depth. By leveraging similar signal acquisition and processing methods, the integration of photoacoustic and ultrasound imaging has introduced a novel hybrid imaging modality suitable for clinical applications. Photoacoustic-ultrasound imaging allows for non-invasive, high-resolution, and deep-penetrating imaging, providing a wealth of image information. In recent years, with the deepening research and the expanding biomedical application scenarios of photoacoustic-ultrasound bimodal systems, the immense potential of photoacoustic-ultrasound bimodal imaging in basic research and clinical applications has been demonstrated, with some research achievements already commercialized. In this review, we introduce the principles, technical advantages, and biomedical applications of photoacoustic-ultrasound bimodal imaging techniques, specifically focusing on tomographic, microscopic, and endoscopic imaging modalities. Furthermore, we discuss the future directions of photoacoustic-ultrasound bimodal imaging technology.
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Affiliation(s)
- Yinshi Yu
- Smart Computational Imaging Laboratory (SCILab), School of Electronic and Optical Engineering, Nanjing University of Science and Technology, Nanjing, Jiangsu Province 210094, China; Smart Computational Imaging Research Institute (SCIRI) of Nanjing University of Science and Technology, Nanjing, Jiangsu Province 210019, China; Jiangsu Key Laboratory of Spectral Imaging & Intelligent Sense, Nanjing, Jiangsu Province 210094, China
| | - Ting Feng
- Academy for Engineering & Technology, Fudan University, Shanghai 200433,China.
| | - Haixia Qiu
- First Medical Center of PLA General Hospital, Beijing, China
| | - Ying Gu
- First Medical Center of PLA General Hospital, Beijing, China
| | - Qian Chen
- Smart Computational Imaging Laboratory (SCILab), School of Electronic and Optical Engineering, Nanjing University of Science and Technology, Nanjing, Jiangsu Province 210094, China; Smart Computational Imaging Research Institute (SCIRI) of Nanjing University of Science and Technology, Nanjing, Jiangsu Province 210019, China; Jiangsu Key Laboratory of Spectral Imaging & Intelligent Sense, Nanjing, Jiangsu Province 210094, China
| | - Chao Zuo
- Smart Computational Imaging Laboratory (SCILab), School of Electronic and Optical Engineering, Nanjing University of Science and Technology, Nanjing, Jiangsu Province 210094, China; Smart Computational Imaging Research Institute (SCIRI) of Nanjing University of Science and Technology, Nanjing, Jiangsu Province 210019, China; Jiangsu Key Laboratory of Spectral Imaging & Intelligent Sense, Nanjing, Jiangsu Province 210094, China.
| | - Haigang Ma
- Smart Computational Imaging Laboratory (SCILab), School of Electronic and Optical Engineering, Nanjing University of Science and Technology, Nanjing, Jiangsu Province 210094, China; Smart Computational Imaging Research Institute (SCIRI) of Nanjing University of Science and Technology, Nanjing, Jiangsu Province 210019, China; Jiangsu Key Laboratory of Spectral Imaging & Intelligent Sense, Nanjing, Jiangsu Province 210094, China.
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Petzold J, Schmitter S, Silemek B, Winter L, Speck O, Ittermann B, Seifert F. Investigation of alternative RF power limit control methods for 0.5T, 1.5T, and 3T parallel transmission cardiac imaging: A simulation study. Magn Reson Med 2024; 91:1659-1675. [PMID: 38031517 DOI: 10.1002/mrm.29932] [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: 06/27/2023] [Revised: 10/09/2023] [Accepted: 10/31/2023] [Indexed: 12/01/2023]
Abstract
PURPOSE To investigate safety and performance aspects of parallel-transmit (pTx) RF control-modes for a body coil atB 0 ≤ 3 T $$ {B}_0\le 3\mathrm{T} $$ . METHODS Electromagnetic simulations of 11 human voxel models in cardiac imaging position were conducted forB 0 = 0.5 T $$ {B}_0=0.5\mathrm{T} $$ ,1.5 T $$ 1.5\mathrm{T} $$ and3 T $$ 3\mathrm{T} $$ and a body coil with a configurable number of transmit channels (1, 2, 4, 8, 16). Three safety modes were considered: the 'SAR-controlled mode' (SCM), where specific absorption rate (SAR) is limited directly, a 'phase agnostic SAR-controlled mode' (PASCM), where phase information is neglected, and a 'power-controlled mode' (PCM), where the voltage amplitude for each channel is limited. For either mode, safety limits were established based on a set of 'anchor' simulations and then evaluated in 'target' simulations on previously unseen models. The comparison allowed to derive safety factors accounting for varying patient anatomies. All control modes were compared in terms of theB 1 + $$ {B}_1^{+} $$ amplitude and homogeneity they permit under their respective safety requirements. RESULTS Large safety factors (approximately five) are needed if only one or two anchor models are investigated but they shrink with increasing number of anchors. The achievableB 1 + $$ {B}_1^{+} $$ is highest for SCM but this advantage is reduced when the safety factor is included. PCM appears to be more robust against variations of subjects. PASCM performance is mostly in between SCM and PCM. Compared to standard circularly polarized (CP) excitation, pTx offers minorB 1 + $$ {B}_1^{+} $$ improvements if local SAR limits are always enforced. CONCLUSION PTx body coils can safely be used atB 0 ≤ 3 T $$ {B}_0\le 3\mathrm{T} $$ . Uncertainties in patient anatomy must be accounted for, however, by simulating many models.
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Affiliation(s)
- Johannes Petzold
- Physikalisch-Technische Bundesanstalt (PTB), Braunschweig and Berlin, Germany
- Biomedical Magnetic Resonance, Otto von Guericke University Magdeburg, Magdeburg, Germany
| | - Sebastian Schmitter
- Physikalisch-Technische Bundesanstalt (PTB), Braunschweig and Berlin, Germany
| | - Berk Silemek
- Physikalisch-Technische Bundesanstalt (PTB), Braunschweig and Berlin, Germany
| | - Lukas Winter
- Physikalisch-Technische Bundesanstalt (PTB), Braunschweig and Berlin, Germany
| | - Oliver Speck
- Biomedical Magnetic Resonance, Otto von Guericke University Magdeburg, Magdeburg, Germany
| | - Bernd Ittermann
- Physikalisch-Technische Bundesanstalt (PTB), Braunschweig and Berlin, Germany
| | - Frank Seifert
- Physikalisch-Technische Bundesanstalt (PTB), Braunschweig and Berlin, Germany
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Sun Y, Wang Y, Li W, Li C. Real-time dual-modal photoacoustic and fluorescence small animal imaging. Photoacoustics 2024; 36:100593. [PMID: 38352643 PMCID: PMC10862394 DOI: 10.1016/j.pacs.2024.100593] [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] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 01/30/2024] [Accepted: 01/30/2024] [Indexed: 02/16/2024]
Abstract
By combining optical absorption contrast and acoustic resolution, photoacoustic imaging (PAI) has broken the barrier in depth for high-resolution optical imaging. Meanwhile, Fluorescence imaging (FLI), owing to advantages of high sensitivity and high specificity with abundant fluorescence agents and proteins, has always been playing a key role in live animal studies. Based on different optical contrast mechanisms, PAI and FLI can provide important complementary information to each other. In this work, we uniquely designed a Photoacoustic-Fluorescence (PA-FL) imaging system that provides real-time dual modality imaging, in which a half-ring ultrasonic array is employed for high quality PA tomography and a specially designed optical window allows simultaneous whole-body fluorescence imaging. The performance of this dual modality system was demonstrated in live animal studies, including real-time monitoring of perfusion and metabolic processes of fluorescent dyes. Our study indicates that the PA-FL imaging system has unique potential for live small animal research.
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Affiliation(s)
- Yu Sun
- Department of Biomedical Engineering, School of Future Technology, Peking University, Beijing 100871, China
| | - Yibing Wang
- Department of Biomedical Engineering, School of Future Technology, Peking University, Beijing 100871, China
| | - Wenzhao Li
- Department of Biomedical Engineering, School of Future Technology, Peking University, Beijing 100871, China
| | - Changhui Li
- Department of Biomedical Engineering, School of Future Technology, Peking University, Beijing 100871, China
- National Biomedical Imaging Center, Peking University, Beijing 100871, China
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10
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Fu M, Zhang N, Huang Z, Zhou C, Zhang X, Yuan J, He Q, Yang Y, Zheng H, Liang D, Wu FX, Fan W, Hu Z. OIF-Net: An Optical Flow Registration-Based PET/MR Cross-Modal Interactive Fusion Network for Low-Count Brain PET Image Denoising. IEEE Trans Med Imaging 2024; 43:1554-1567. [PMID: 38096101 DOI: 10.1109/tmi.2023.3342809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
The short frames of low-count positron emission tomography (PET) images generally cause high levels of statistical noise. Thus, improving the quality of low-count images by using image postprocessing algorithms to achieve better clinical diagnoses has attracted widespread attention in the medical imaging community. Most existing deep learning-based low-count PET image enhancement methods have achieved satisfying results, however, few of them focus on denoising low-count PET images with the magnetic resonance (MR) image modality as guidance. The prior context features contained in MR images can provide abundant and complementary information for single low-count PET image denoising, especially in ultralow-count (2.5%) cases. To this end, we propose a novel two-stream dual PET/MR cross-modal interactive fusion network with an optical flow pre-alignment module, namely, OIF-Net. Specifically, the learnable optical flow registration module enables the spatial manipulation of MR imaging inputs within the network without any extra training supervision. Registered MR images fundamentally solve the problem of feature misalignment in the multimodal fusion stage, which greatly benefits the subsequent denoising process. In addition, we design a spatial-channel feature enhancement module (SC-FEM) that considers the interactive impacts of multiple modalities and provides additional information flexibility in both the spatial and channel dimensions. Furthermore, instead of simply concatenating two extracted features from these two modalities as an intermediate fusion method, the proposed cross-modal feature fusion module (CM-FFM) adopts cross-attention at multiple feature levels and greatly improves the two modalities' feature fusion procedure. Extensive experimental assessments conducted on real clinical datasets, as well as an independent clinical testing dataset, demonstrate that the proposed OIF-Net outperforms the state-of-the-art methods.
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Soydan DA, Top CB, Gençer NG. On the utilization of the adjoint method in microwave tomography. Int J Numer Method Biomed Eng 2024:e3818. [PMID: 38556485 DOI: 10.1002/cnm.3818] [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] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Revised: 03/14/2024] [Accepted: 03/17/2024] [Indexed: 04/02/2024]
Abstract
In microwave imaging, the adjoint method is widely used for the efficient calculation of the update direction, which is then used to update the unknown model parameter. However, the utilization and the formulation of the adjoint method differ significantly depending on the imaging scenario and the applied optimization algorithm. Because of the problem-specific nature of the adjoint formulations, the dissimilarities between the adjoint calculations may be overlooked. Here, we have classified the adjoint method formulations into two groups: the direct and indirect methods. The direct method involves calculating the derivative of the cost function, whereas, in the indirect method, the derivative of the predicted data is calculated. In this review, the direct and indirect adjoint methods are presented, compared, and discussed. The formulations are explicitly derived using the two-dimensional wave equation in frequency and time domains. Finite-difference time-domain simulations are conducted to show the different uses of the adjoint methods for both single source-multiple receiver, and multiple transceiver scenarios. This study demonstrated that an appropriate adjoint method selection is significant to achieve improved computational efficiency for the applied optimization algorithm.
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Affiliation(s)
- Damla Alptekin Soydan
- Electrical and Electronics Engineering Department, Middle East Technical University, Ankara, Turkey
- ASELSAN A.Ş, Ankara, Turkey
| | | | - Nevzat G Gençer
- Electrical and Electronics Engineering Department, Middle East Technical University, Ankara, Turkey
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12
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Zapien-Campos B, Ahmadi Ganjeh Z, Both S, Dendooven P. Measurement of the 12C(p,n) 12N reaction cross section below 150 MeV. Phys Med Biol 2024; 69:075025. [PMID: 38382103 DOI: 10.1088/1361-6560/ad2b97] [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: 10/06/2023] [Accepted: 02/21/2024] [Indexed: 02/23/2024]
Abstract
Objective. Proton therapy currently faces challenges from clinical complications on organs-at-risk due to range uncertainties. To address this issue, positron emission tomography (PET) of the proton-induced11C and15O activity has been used to provide feedback on the proton range. However, this approach is not instantaneous due to the relatively long half-lives of these nuclides. An alternative nuclide,12N (half-life 11 ms), shows promise for real-timein vivoproton range verification. Development of12N imaging requires better knowledge of its production reaction cross section.Approach. The12C(p,n)12N reaction cross section was measured by detecting positron activity of graphite targets irradiated with 66.5, 120, and 150 MeV protons. A pulsed beam delivery with 0.7-2 × 108protons per pulse was used. The positron activity was measured during the beam-off periods using a dual-head Siemens Biograph mCT PET scanner. The12N production was determined from activity time histograms.Main results. The cross section was calculated for 11 energies, ranging from 23.5 to 147 MeV, using information on the experimental setup and beam delivery. Through a comprehensive uncertainty propagation analysis, a statistical uncertainty of 2.6%-5.8% and a systematic uncertainty of 3.3%-4.6% were achieved. Additionally, a comparison between measured and simulated scanner sensitivity showed a scaling factor of 1.25 (±3%). Despite this, there was an improvement in the precision of the cross section measurement compared to values reported by the only previous study.Significance. Short-lived12N imaging is promising for real-timein vivoverification of the proton range to reduce clinical complications in proton therapy. The verification procedure requires experimental knowledge of the12N production cross section for proton energies of clinical importance, to be incorporated in a Monte Carlo framework for12N imaging prediction. This study is the first to achieve a precise measurement of the12C(p,n)12N nuclear cross section for such proton energies.
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Affiliation(s)
- Brian Zapien-Campos
- Particle Therapy Research Center (PARTREC), Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Zahra Ahmadi Ganjeh
- Particle Therapy Research Center (PARTREC), Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Stefan Both
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Peter Dendooven
- Particle Therapy Research Center (PARTREC), Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
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13
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Lin HCA, Deán-Ben XL, Ozbek A, Shao YH, Lafci B, Razansky D. Hybrid spherical array for combined volumetric optoacoustic and B-mode ultrasound imaging. Opt Lett 2024; 49:1469-1472. [PMID: 38489427 DOI: 10.1364/ol.503118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Accepted: 01/14/2024] [Indexed: 03/17/2024]
Abstract
Optoacoustic (OA) imaging has achieved tremendous progress with state-of-the-art systems providing excellent functional and molecular contrast, centimeter scale penetration into living tissues, and ultrafast imaging performance, making it highly suitable for handheld imaging in the clinics. OA can greatly benefit from efficient integration with ultrasound (US) imaging, which remains the routine method in bedside clinical diagnostics. However, such integration has not been straightforward since the two modalities typically involve different image acquisition strategies. Here, we present a new, to our knowledge, hybrid optoacoustic ultrasound (OPUS) imaging approach employing a spherical array with dedicated segments for each modality to enable volumetric OA imaging merged with conventional B-mode US. The system performance is subsequently showcased in healthy human subjects. The new OPUS approach hence represents an important step toward establishing OA in point-of-care diagnostic settings.
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14
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Kazemivalipour E, Wald LL, Guerin B. Comparison of tight-fitting 7T parallel-transmit head array designs using excitation uniformity and local specific absorption rate metrics. Magn Reson Med 2024; 91:1209-1224. [PMID: 37927216 PMCID: PMC10848211 DOI: 10.1002/mrm.29900] [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: 02/11/2023] [Revised: 09/15/2023] [Accepted: 10/06/2023] [Indexed: 11/07/2023]
Abstract
PURPOSE We model the performance of parallel transmission (pTx) arrays with 8, 16, 24, and 32 channels and varying loop sizes built on a close-fitting helmet for brain imaging at 7 T and compare their local specific absorption rate (SAR) and flip-angle performances to that of birdcage coil (used as a baseline) and cylindrical 8-channel and 16-channel pTx coils (single-row and dual-row). METHODS We use the co-simulation approach along with MATLAB scripting for batch-mode simulation of the coils. For each coil, we extracted B1 + maps and SAR matrices, which we compressed using the virtual observation points algorithm, and designed slice-selective RF shimming pTx pulses with multiple local SAR and peak power constraints to generate L-curves in the transverse, coronal, and sagittal orientations. RESULTS Helmet designs outperformed cylindrical pTx arrays at a constant number of channels in the flip-angle uniformity at a constant local SAR metric: up to 29% for 8-channel arrays, and up to 34% for 16-channel arrays, depending on the slice orientation. For all helmet arrays, increasing the loop diameter led to better local SAR versus flip-angle uniformity tradeoffs, although this effect was more pronounced for the 8-channel and 16-channel systems than the 24-channel and 32-channel systems, as the former have more limited degrees of freedom and therefore benefit more from loop-size optimization. CONCLUSION Helmet pTx arrays significantly outperformed cylindrical arrays with the same number of channels in local SAR and flip-angle uniformity metrics. This improvement was especially pronounced for non-transverse slice excitations. Loop diameter optimization for helmets appears to favor large loops, compatible with nearest-neighbor decoupling by overlap.
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Affiliation(s)
- Ehsan Kazemivalipour
- A. A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, Massachusetts, USA
- Harvard Medical School, Boston, Massachusetts, USA
| | - Lawrence L. Wald
- A. A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, Massachusetts, USA
- Harvard Medical School, Boston, Massachusetts, USA
- Harvard-MIT Division of Health Sciences Technology, Cambridge, Massachusetts, USA
| | - Bastien Guerin
- A. A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, Massachusetts, USA
- Harvard Medical School, Boston, Massachusetts, USA
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Nozdriukhin D, Kalva SK, Özsoy C, Reiss M, Li W, Razansky D, Deán‐Ben XL. Multi-Scale Volumetric Dynamic Optoacoustic and Laser Ultrasound (OPLUS) Imaging Enabled by Semi-Transparent Optical Guidance. Adv Sci (Weinh) 2024; 11:e2306087. [PMID: 38115760 PMCID: PMC10953719 DOI: 10.1002/advs.202306087] [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] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 11/05/2023] [Indexed: 12/21/2023]
Abstract
Major biological discoveries are made by interrogating living organisms with light. However, the limited penetration of un-scattered photons within biological tissues limits the depth range covered by optical methods. Deep-tissue imaging is achieved by combining light and ultrasound. Optoacoustic imaging exploits the optical generation of ultrasound to render high-resolution images at depths unattainable with optical microscopy. Recently, laser ultrasound has been suggested as a means of generating broadband acoustic waves for high-resolution pulse-echo ultrasound imaging. Herein, an approach is proposed to simultaneously interrogate biological tissues with light and ultrasound based on layer-by-layer coating of silica optical fibers with a controlled degree of transparency. The time separation between optoacoustic and ultrasound signals collected with a custom-made spherical array transducer is exploited for simultaneous 3D optoacoustic and laser ultrasound (OPLUS) imaging with a single laser pulse. OPLUS is shown to enable large-scale anatomical characterization of tissues along with functional multi-spectral imaging of chromophores and assessment of cardiac dynamics at ultrafast rates only limited by the pulse repetition frequency of the laser. The suggested approach provides a flexible and scalable means for developing a new generation of systems synergistically combining the powerful capabilities of optoacoustics and ultrasound imaging in biology and medicine.
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Affiliation(s)
- Daniil Nozdriukhin
- Institute of Pharmacology and Toxicology and Institute for Biomedical EngineeringFaculty of MedicineUniversity of ZürichWinterthurerstrasse 190Zürich8057Switzerland
- Institute for Biomedical Engineering, Department of Information Technology and Electrical EngineeringETH ZürichWolfgang‐Pauli‐Strasse 27Zürich8093Switzerland
| | - Sandeep Kumar Kalva
- Institute of Pharmacology and Toxicology and Institute for Biomedical EngineeringFaculty of MedicineUniversity of ZürichWinterthurerstrasse 190Zürich8057Switzerland
- Institute for Biomedical Engineering, Department of Information Technology and Electrical EngineeringETH ZürichWolfgang‐Pauli‐Strasse 27Zürich8093Switzerland
| | - Cagla Özsoy
- Institute of Pharmacology and Toxicology and Institute for Biomedical EngineeringFaculty of MedicineUniversity of ZürichWinterthurerstrasse 190Zürich8057Switzerland
- Institute for Biomedical Engineering, Department of Information Technology and Electrical EngineeringETH ZürichWolfgang‐Pauli‐Strasse 27Zürich8093Switzerland
| | - Michael Reiss
- Institute of Pharmacology and Toxicology and Institute for Biomedical EngineeringFaculty of MedicineUniversity of ZürichWinterthurerstrasse 190Zürich8057Switzerland
- Institute for Biomedical Engineering, Department of Information Technology and Electrical EngineeringETH ZürichWolfgang‐Pauli‐Strasse 27Zürich8093Switzerland
| | - Weiye Li
- Institute of Pharmacology and Toxicology and Institute for Biomedical EngineeringFaculty of MedicineUniversity of ZürichWinterthurerstrasse 190Zürich8057Switzerland
- Institute for Biomedical Engineering, Department of Information Technology and Electrical EngineeringETH ZürichWolfgang‐Pauli‐Strasse 27Zürich8093Switzerland
| | - Daniel Razansky
- Institute of Pharmacology and Toxicology and Institute for Biomedical EngineeringFaculty of MedicineUniversity of ZürichWinterthurerstrasse 190Zürich8057Switzerland
- Institute for Biomedical Engineering, Department of Information Technology and Electrical EngineeringETH ZürichWolfgang‐Pauli‐Strasse 27Zürich8093Switzerland
| | - Xosé Luís Deán‐Ben
- Institute of Pharmacology and Toxicology and Institute for Biomedical EngineeringFaculty of MedicineUniversity of ZürichWinterthurerstrasse 190Zürich8057Switzerland
- Institute for Biomedical Engineering, Department of Information Technology and Electrical EngineeringETH ZürichWolfgang‐Pauli‐Strasse 27Zürich8093Switzerland
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16
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Herraiz JL, Lopez-Montes A, Badal A. MCGPU-PET: An Open-Source Real-Time Monte Carlo PET Simulator. Comput Phys Commun 2024; 296:109008. [PMID: 38145286 PMCID: PMC10735232 DOI: 10.1016/j.cpc.2023.109008] [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: 12/26/2023]
Abstract
Monte Carlo (MC) simulations are commonly used to model the emission, transmission, and/or detection of radiation in Positron Emission Tomography (PET). In this work, we introduce a new open-source MC software for PET simulation, MCGPU-PET, which has been designed to fully exploit the computing capabilities of modern GPUs to simulate the acquisition of more than 100 million coincidences per second from voxelized sources and material distributions. The new simulator is an extension of the PENELOPE-based MCGPU code previously used in cone-beam CT and mammography applications. We validated the accuracy of the accelerated code by comparing it to GATE and PeneloPET simulations achieving an agreement within 10 percent approximately. As an example application of the code for fast estimation of PET coincidences, a scan of the NEMA IQ phantom was simulated. A fully 3D sinogram with 6382 million true coincidences and 731 million scatter coincidences was generated in 54 seconds in one GPU. MCGPU-PET provides an estimation of true and scatter coincidences and spurious background (for positron-gamma emitters such as 124I) at a rate 3 orders of magnitude faster than CPU-based MC simulators. This significant speed-up enables the use of the code for accurate scatter and prompt-gamma background estimations within an iterative image reconstruction process.
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Affiliation(s)
- Joaquin L. Herraiz
- Complutense University of Madrid, EMFTEL, Grupo de Física Nuclear and IPARCOS, Madrid, 28040, Spain
- Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdiSSC), Madrid,28040, Spain
| | - Alejandro Lopez-Montes
- Complutense University of Madrid, EMFTEL, Grupo de Física Nuclear and IPARCOS, Madrid, 28040, Spain
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, 21205, United States of America
| | - Andreu Badal
- DIDSR, OSEL, CDRH, US Food and Drug Administration, Silver Spring, MD, 20993, USA
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17
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Lu X, Liang X, Liu W, Miao X, Guan X. ReeGAN: MRI image edge-preserving synthesis based on GANs trained with misaligned data. Med Biol Eng Comput 2024:10.1007/s11517-024-03035-w. [PMID: 38396277 DOI: 10.1007/s11517-024-03035-w] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Accepted: 01/27/2024] [Indexed: 02/25/2024]
Abstract
As a crucial medical examination technique, different modalities of magnetic resonance imaging (MRI) complement each other, offering multi-angle and multi-dimensional insights into the body's internal information. Therefore, research on MRI cross-modality conversion is of great significance, and many innovative techniques have been explored. However, most methods are trained on well-aligned data, and the impact of misaligned data has not received sufficient attention. Additionally, many methods focus on transforming the entire image and ignore crucial edge information. To address these challenges, we propose a generative adversarial network based on multi-feature fusion, which effectively preserves edge information while training on noisy data. Notably, we consider images with limited range random transformations as noisy labels and use an additional small auxiliary registration network to help the generator adapt to the noise distribution. Moreover, we inject auxiliary edge information to improve the quality of synthesized target modality images. Our goal is to find the best solution for cross-modality conversion. Comprehensive experiments and ablation studies demonstrate the effectiveness of the proposed method.
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Affiliation(s)
- Xiangjiang Lu
- Guangxi Key Lab of Multi-Source Information Mining & Security, School of Computer Science and Engineering & School of Software, Guangxi Normal University, Guilin, 541004, China.
| | - Xiaoshuang Liang
- Guangxi Key Lab of Multi-Source Information Mining & Security, School of Computer Science and Engineering & School of Software, Guangxi Normal University, Guilin, 541004, China
| | - Wenjing Liu
- Guangxi Key Lab of Multi-Source Information Mining & Security, School of Computer Science and Engineering & School of Software, Guangxi Normal University, Guilin, 541004, China
| | - Xiuxia Miao
- Guangxi Key Lab of Multi-Source Information Mining & Security, School of Computer Science and Engineering & School of Software, Guangxi Normal University, Guilin, 541004, China
| | - Xianglong Guan
- Guangxi Key Lab of Multi-Source Information Mining & Security, School of Computer Science and Engineering & School of Software, Guangxi Normal University, Guilin, 541004, China
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18
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Peña-Acosta MM, Gallardo S, Lorduy-Alós M, Verdú G. Application of NEMA protocols to verify GATE models based on the Digital Biograph Vision and the Biograph Vision Quadra scanners. Z Med Phys 2024:S0939-3889(24)00005-9. [PMID: 38341373 DOI: 10.1016/j.zemedi.2024.01.005] [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: 04/05/2023] [Revised: 01/18/2024] [Accepted: 01/19/2024] [Indexed: 02/12/2024]
Abstract
PURPOSE The Monte Carlo method is an effective tool to simulate and verify PET systems. Furthermore, it can help in the design and optimization of new medical imaging devices and algorithms. In this framework, the goal of this work is to verify the GATE toolkit performance when applied to simulate two Siemens Healthineers PET scanners: a standard axial field-of-view Biograph Vision scanner and the new long axial field-of-view Biograph Vision Quadra scanner. METHODS The simulation toolkit GATE is based on GEANT4, comprising its main functionalities and a set of domain-specific features in the field of medical physics. To accomplish our purpose, the guidelines described in the NEMA NU 2-2018 protocol are reproduced. Then the simulated results are compared to experimental data available in the literature for both PET scanners. The assessment of the models includes different studies of sensitivity, count rate performances, spatial resolution and image quality. These tests are intended to evaluate the image quality of PET devices. RESULTS In the spatial resolution test, relative errors lower than 8% are obtained between the experiments and GATE models. The sensitivity is 17.2 cps/kBq (Vision) and 175.9 cps/kBq (Quadra), representing relative differences with the experiment of 6% and 0.3%, respectively. Deviations from peak NECR are less than 9%. In the Image Quality test, the contrast recovery coefficient for hot spheres, with 8 iterations and 5 subsets, ranges between 57-83% for Vision and 54-86% for Quadra. These values represent a maximum deviation between the simulations and the experiments of 10% for the Quadra scanner. In the case of the Vision scanner, the highest difference is observed for the 10 mm sphere (∼38%) due to the higher contrast recovery of the experiment caused by the Gibbs artifact from the use of PSF reconstruction. CONCLUSIONS The results of the simulations have provided evidence of a good agreement between the experimental data and the results obtained with GATE. Thus, this work supports the capability of this MC toolkit to accurately simulate the models of the Vision and Quadra scanners. This study has laid the basis for further research in this field and has identified several areas that could be explored.
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Affiliation(s)
- Miriam Magela Peña-Acosta
- Instituto Universitario de Seguridad Industrial, Radiofísica y Medioambiental. Universitat Politècnica de València, Camí de Vera(s/n), 46022 València, Spain
| | - Sergio Gallardo
- Instituto Universitario de Seguridad Industrial, Radiofísica y Medioambiental. Universitat Politècnica de València, Camí de Vera(s/n), 46022 València, Spain.
| | - María Lorduy-Alós
- Instituto Universitario de Seguridad Industrial, Radiofísica y Medioambiental. Universitat Politècnica de València, Camí de Vera(s/n), 46022 València, Spain
| | - Gumersindo Verdú
- Instituto Universitario de Seguridad Industrial, Radiofísica y Medioambiental. Universitat Politècnica de València, Camí de Vera(s/n), 46022 València, Spain
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Vu T, Klippel P, Canning AJ, Ma C, Zhang H, Kasatkina LA, Tang Y, Xia J, Verkhusha VV, Vo-Dinh T, Jing Y, Yao J. On the Importance of Low-Frequency Signals in Functional and Molecular Photoacoustic Computed Tomography. IEEE Trans Med Imaging 2024; 43:771-783. [PMID: 37773898 PMCID: PMC10932611 DOI: 10.1109/tmi.2023.3320668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/01/2023]
Abstract
In photoacoustic computed tomography (PACT) with short-pulsed laser excitation, wideband acoustic signals are generated in biological tissues with frequencies related to the effective shapes and sizes of the optically absorbing targets. Low-frequency photoacoustic signal components correspond to slowly varying spatial features and are often omitted during imaging due to the limited detection bandwidth of the ultrasound transducer, or during image reconstruction as undesired background that degrades image contrast. Here we demonstrate that low-frequency photoacoustic signals, in fact, contain functional and molecular information, and can be used to enhance structural visibility, improve quantitative accuracy, and reduce spare-sampling artifacts. We provide an in-depth theoretical analysis of low-frequency signals in PACT, and experimentally evaluate their impact on several representative PACT applications, such as mapping temperature in photothermal treatment, measuring blood oxygenation in a hypoxia challenge, and detecting photoswitchable molecular probes in deep organs. Our results strongly suggest that low-frequency signals are important for functional and molecular PACT.
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de Scals S, Fraile LM, Udías JM, Martínez Cortés L, Oteo M, Morcillo MÁ, Carreras-Delgado JL, Cabrera-Martín MN, España S. Feasibility study of a SiPM-fiber detector for non-invasive measurement of arterial input function for preclinical and clinical positron emission tomography. EJNMMI Phys 2024; 11:12. [PMID: 38291187 PMCID: PMC10828322 DOI: 10.1186/s40658-024-00618-2] [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: 10/18/2023] [Accepted: 01/19/2024] [Indexed: 02/01/2024] Open
Abstract
Pharmacokinetic positron emission tomography (PET) studies rely on the measurement of the arterial input function (AIF), which represents the time-activity curve of the radiotracer concentration in the blood plasma. Traditionally, obtaining the AIF requires invasive procedures, such as arterial catheterization, which can be challenging, time-consuming, and associated with potential risks. Therefore, the development of non-invasive techniques for AIF measurement is highly desirable. This study presents a detector for the non-invasive measurement of the AIF in PET studies. The detector is based on the combination of scintillation fibers and silicon photomultipliers (SiPMs) which leads to a very compact and rugged device. The feasibility of the detector was assessed through Monte Carlo simulations conducted on mouse tail and human wrist anatomies studying relevant parameters such as energy spectrum, detector efficiency and minimum detectable activity (MDA). The simulations involved the use of 18F and 68Ga isotopes, which exhibit significantly different positron ranges. In addition, several prototypes were built in order to study the different components of the detector including the scintillation fiber, the coating of the fiber, the SiPMs, and the operating configuration. Finally, the simulations were compared with experimental measurements conducted using a tube filled with both 18F and 68Ga to validate the obtained results. The MDA achieved for both anatomies (approximately 1000 kBq/mL for mice and 1 kBq/mL for humans) falls below the peak radiotracer concentrations typically found in PET studies, affirming the feasibility of conducting non-invasive AIF measurements with the fiber detector. The sensitivity for measurements with a tube filled with 18F (68Ga) was 1.2 (2.07) cps/(kBq/mL), while for simulations, it was 2.81 (6.23) cps/(kBq/mL). Further studies are needed to validate these results in pharmacokinetic PET studies.
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Affiliation(s)
- Sara de Scals
- Grupo de Física Nuclear, EMFTEL and IPARCOS, Universidad Complutense de Madrid, Madrid, Spain
- Instituto de Investigación del Hospital Clínico San Carlos (IdISSC), Madrid, Spain
| | - Luis Mario Fraile
- Grupo de Física Nuclear, EMFTEL and IPARCOS, Universidad Complutense de Madrid, Madrid, Spain
- Instituto de Investigación del Hospital Clínico San Carlos (IdISSC), Madrid, Spain
| | - José Manuel Udías
- Grupo de Física Nuclear, EMFTEL and IPARCOS, Universidad Complutense de Madrid, Madrid, Spain
- Instituto de Investigación del Hospital Clínico San Carlos (IdISSC), Madrid, Spain
| | - Laura Martínez Cortés
- Unidad de Aplicaciones Médicas de las Radiaciones Ionizantes, Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Madrid, Spain
| | - Marta Oteo
- Unidad de Aplicaciones Médicas de las Radiaciones Ionizantes, Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Madrid, Spain
| | - Miguel Ángel Morcillo
- Unidad de Aplicaciones Médicas de las Radiaciones Ionizantes, Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Madrid, Spain
| | | | | | - Samuel España
- Grupo de Física Nuclear, EMFTEL and IPARCOS, Universidad Complutense de Madrid, Madrid, Spain.
- Instituto de Investigación del Hospital Clínico San Carlos (IdISSC), Madrid, Spain.
- Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain.
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Galve P, Arias-Valcayo F, Villa-Abaunza A, Ibáñez P, Udías JM. UMC-PET: a fast and flexible Monte Carlo PET simulator. Phys Med Biol 2024; 69:035018. [PMID: 38198727 DOI: 10.1088/1361-6560/ad1cf9] [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: 03/16/2023] [Accepted: 01/10/2024] [Indexed: 01/12/2024]
Abstract
Objective.The GPU-based Ultra-fast Monte Carlo positron emission tomography simulator (UMC-PET) incorporates the physics of the emission, transport and detection of radiation in PET scanners. It includes positron range, non-colinearity, scatter and attenuation, as well as detector response. The objective of this work is to present and validate UMC-PET as a a multi-purpose, accurate, fast and flexible PET simulator.Approach.We compared UMC-PET against PeneloPET, a well-validated MC PET simulator, both in preclinical and clinical scenarios. Different phantoms for scatter fraction (SF) assessment following NEMA protocols were simulated in a 6R-SuperArgus and a Biograph mMR scanner, comparing energy histograms, NEMA SF, and sensitivity for different energy windows. A comparison with real data reported in the literature on the Biograph scanner is also shown.Main results.NEMA SF and sensitivity estimated by UMC-PET where within few percent of PeneloPET predictions. The discrepancies can be attributed to small differences in the physics modeling. Running in a 11 GB GeForce RTX 2080 Ti GPU, UMC-PET is ∼1500 to ∼2000 times faster than PeneloPET executing in a single core Intel(R) Xeon(R) CPU W-2155 @ 3.30 GHz.Significance.UMC-PET employs a voxelized scheme for the scanner, patient adjacent objects (such as shieldings or the patient bed), and the activity distribution. This makes UMC-PET extremely flexible. Its high simulation speed allows applications such as MC scatter correction, faster SRM estimation for complex scanners, or even MC iterative image reconstruction.
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Affiliation(s)
- Pablo Galve
- Grupo de Física Nuclear, EMFTEL & IPARCOS, Universidad Complutense de Madrid, CEI Moncloa, 28040 Madrid, Spain
- Université Paris Cité, Inserm, PARCC, F-75015 Paris, France
- Health Research Institute of the Hospital Clínico San Carlos (IdISSC), Madrid, Spain
| | - Fernando Arias-Valcayo
- Grupo de Física Nuclear, EMFTEL & IPARCOS, Universidad Complutense de Madrid, CEI Moncloa, 28040 Madrid, Spain
- Health Research Institute of the Hospital Clínico San Carlos (IdISSC), Madrid, Spain
| | - Amaia Villa-Abaunza
- Grupo de Física Nuclear, EMFTEL & IPARCOS, Universidad Complutense de Madrid, CEI Moncloa, 28040 Madrid, Spain
| | - Paula Ibáñez
- Grupo de Física Nuclear, EMFTEL & IPARCOS, Universidad Complutense de Madrid, CEI Moncloa, 28040 Madrid, Spain
- Health Research Institute of the Hospital Clínico San Carlos (IdISSC), Madrid, Spain
| | - José Manuel Udías
- Grupo de Física Nuclear, EMFTEL & IPARCOS, Universidad Complutense de Madrid, CEI Moncloa, 28040 Madrid, Spain
- Health Research Institute of the Hospital Clínico San Carlos (IdISSC), Madrid, Spain
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22
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Zhang C, Tan Z, Tian C. Point spread function modeling for photoacoustic tomography - I: three-dimensional detection geometries. Opt Express 2024; 32:1063-1087. [PMID: 38297668 DOI: 10.1364/oe.499039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Accepted: 11/06/2023] [Indexed: 02/02/2024]
Abstract
Photoacoustic computed tomography (PACT) has been under intensive investigation as a promising noninvasive biomedical imaging modality. Various acoustic detector arrays have been developed to achieve enhanced imaging performance. In this paper, we study the effect of the detection geometry on image quality through point spread function (PSF) modeling based on back-projection image reconstruction. Three commonly-used three-dimensional detection geometries, namely, spherical, cylindrical, and planar detector arrays, are investigated. The effect of detector bandwidth and aperture on PSF in these detection geometries is also studied. This work provides a performance evaluation tool for acoustic detector arrays used in PACT and can be helpful in the design and selection of detector arrays in practical imaging applications.
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23
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Iliaskou C, Rossi G, Sachpazidis I, Boronikolas V, Gainey M, Baltas D. Evaluation of RADIANCE Monte Carlo algorithm for treatment planning in electron based Intraoperative Radiotherapy (IOERT). Z Med Phys 2024:S0939-3889(23)00149-6. [PMID: 38182457 DOI: 10.1016/j.zemedi.2023.12.002] [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: 06/22/2023] [Revised: 12/01/2023] [Accepted: 12/04/2023] [Indexed: 01/07/2024]
Abstract
PURPOSE To perform experimental as well as independent Monte Carlo (MC) evaluation of the MC algorithm implemented in RADIANCE version 4.0.8, a dedicated treatment planning system (TPS) for 3D electron dose calculations in intraoperative radiation therapy (IOERT). METHODS AND MATERIALS The MOBETRON 2000 (IntraOp Medical Corporation, Sunnyvale, CA) IOERT accelerator was employed. PDD and profiles for five cylindrical plastic applicators with 50-90 mm diameter and 0°, 30° beveling were measured in a water phantom, at nominal energies of 6, 9 and 12 MeV. Additional PDD measurements were performed for all the energies without applicator. MC modeling of the MOBETRON was performed with the user code BEAMnrc and egs_chamber of the MC simulation toolkit EGSnrc. The generated phase space files of the two 0°-bevel applicators (50 mm, 80 mm) and three energies in both RADIANCE and BEAMnrc, were used to determine PDD and profiles in various set-ups of virtual water phantoms with air and bone inhomogeneities. 3D dose distributions were also calculated in image data sets of an anthropomorphic tissue-equivalent pelvis phantom. Image acquisitions were realized with a CT scanner (Philips Big Bore CT, Netherlands). Gamma analysis was applied to quantify the deviations of the RADIANCE calculations to the measurements and EGSnrc calculations. Gamma criteria normalized to the global maximum were investigated between 2%, 2 mm and 3%, 3 mm. RESULTS RADIANCE MC calculations satisfied the gamma criteria of 3%, 3 mm with a tolerance limit of 85% passing rate compared to in- water phantom measurements, except for the dose profiles of the 30° beveled applicators. Mismatches lay in surface doses, in umbra regions and in the beveled end of the 30° applicators. A very good agreement to the EGSnrc calculations in heterogeneous media was observed. Deviations were more pronounced for the larger applicator diameter and higher electron energy. In 3D dose comparisons in the anthropomorphic phantom, gamma passing rates were higher than 96 % for both simulated applicators. CONCLUSIONS RADIANCE MC algorithm agrees within 3%, 3 mm criteria with in-water phantom measurements and EGSnrc MC dose distributions in heterogeneous media for 0°-bevel applicators. The user should be aware of missing scattering components and the 30° beveled applicators should be used with attention.
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Affiliation(s)
- Charoula Iliaskou
- Division of Medical Physics, Department of Radiation Oncology, University Medical Center, Freiburg 79106, Germany; German Cancer Consortium (DKTK), Partner Site Freiburg, German Cancer Research Center (DKFZ), Heidelberg 69120, Germany.
| | - Giulio Rossi
- Division of Medical Physics, Department of Radiation Oncology, University Medical Center, Freiburg 79106, Germany; German Cancer Consortium (DKTK), Partner Site Freiburg, German Cancer Research Center (DKFZ), Heidelberg 69120, Germany
| | - Ilias Sachpazidis
- Division of Medical Physics, Department of Radiation Oncology, University Medical Center, Freiburg 79106, Germany; German Cancer Consortium (DKTK), Partner Site Freiburg, German Cancer Research Center (DKFZ), Heidelberg 69120, Germany
| | - Vasilios Boronikolas
- Division of Medical Physics, Department of Radiation Oncology, University Medical Center, Freiburg 79106, Germany; German Cancer Consortium (DKTK), Partner Site Freiburg, German Cancer Research Center (DKFZ), Heidelberg 69120, Germany
| | - Mark Gainey
- Division of Medical Physics, Department of Radiation Oncology, University Medical Center, Freiburg 79106, Germany; German Cancer Consortium (DKTK), Partner Site Freiburg, German Cancer Research Center (DKFZ), Heidelberg 69120, Germany
| | - Dimos Baltas
- Division of Medical Physics, Department of Radiation Oncology, University Medical Center, Freiburg 79106, Germany; German Cancer Consortium (DKTK), Partner Site Freiburg, German Cancer Research Center (DKFZ), Heidelberg 69120, Germany
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Lindemann ME, Gratz M, Grafe H, Jannusch K, Umutlu L, Quick HH. Systematic evaluation of human soft tissue attenuation correction in whole-body PET/MR: Implications from PET/CT for optimization of MR-based AC in patients with normal lung tissue. Med Phys 2024; 51:192-208. [PMID: 38060671 DOI: 10.1002/mp.16863] [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: 05/04/2023] [Revised: 11/10/2023] [Accepted: 11/16/2023] [Indexed: 01/10/2024] Open
Abstract
BACKGROUND Attenuation correction (AC) is an important methodical step in positron emission tomography/magnetic resonance imaging (PET/MRI) to correct for attenuated and scattered PET photons. PURPOSE The overall quality of magnetic resonance (MR)-based AC in whole-body PET/MRI was evaluated in direct comparison to computed tomography (CT)-based AC serving as reference. The quantitative impact of isolated tissue classes in the MR-AC was systematically investigated to identify potential optimization needs and strategies. METHODS Data of n = 60 whole-body PET/CT patients with normal lung tissue and without metal implants/prostheses were used to generate six different AC-models based on the CT data for each patient, simulating variations of MR-AC. The original continuous CT-AC (CT-org) is referred to as reference. A pseudo MR-AC (CT-mrac), generated from CT data, with four tissue classes and a bone atlas represents the MR-AC. Relative difference in linear attenuation coefficients (LAC) and standardized uptake values were calculated. From the results two improvements regarding soft tissue AC and lung AC were proposed and evaluated. RESULTS The overall performance of MR-AC is in good agreement compared to CT-AC. Lungs, heart, and bone tissue were identified as the regions with most deviation to the CT-AC (myocardium -15%, bone tissue -14%, and lungs ±20%). Using single-valued LACs for AC in the lung only provides limited accuracy. For improved soft tissue AC, splitting the combined soft tissue class into muscles and organs each with adapted LAC could reduce the deviations to the CT-AC to < ±1%. For improved lung AC, applying a gradient LAC in the lungs could remarkably reduce over- or undercorrections in PET signal compared to CT-AC (±5%). CONCLUSIONS The AC is important to ensure best PET image quality and accurate PET quantification for diagnostics and radiotherapy planning. The optimized segment-based AC proposed in this study, which was evaluated on PET/CT data, inherently reduces quantification bias in normal lung tissue and soft tissue compared to the CT-AC reference.
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Affiliation(s)
- Maike E Lindemann
- High-Field and Hybrid MR Imaging, University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | - Marcel Gratz
- High-Field and Hybrid MR Imaging, University Hospital Essen, University Duisburg-Essen, Essen, Germany
- Erwin L. Hahn Institute for Magnetic Resonance Imaging, University Duisburg-Essen, Essen, Germany
| | - Hong Grafe
- Department of Nuclear Medicine, University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | - Kai Jannusch
- Department of Diagnostic and Interventional Radiology, University Hospital Duesseldorf, University Duesseldorf, Duesseldorf, Germany
| | - Lale Umutlu
- Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Harald H Quick
- High-Field and Hybrid MR Imaging, University Hospital Essen, University Duisburg-Essen, Essen, Germany
- Erwin L. Hahn Institute for Magnetic Resonance Imaging, University Duisburg-Essen, Essen, Germany
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Susmelj AK, Lafci B, Ozdemir F, Davoudi N, Deán-Ben XL, Perez-Cruz F, Razansky D. Signal domain adaptation network for limited-view optoacoustic tomography. Med Image Anal 2024; 91:103012. [PMID: 37922769 DOI: 10.1016/j.media.2023.103012] [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: 12/21/2022] [Revised: 09/19/2023] [Accepted: 10/18/2023] [Indexed: 11/07/2023]
Abstract
Optoacoustic (OA) imaging is based on optical excitation of biological tissues with nanosecond-duration laser pulses and detection of ultrasound (US) waves generated by thermoelastic expansion following light absorption. The image quality and fidelity of OA images critically depend on the extent of tomographic coverage provided by the US detector arrays. However, full tomographic coverage is not always possible due to experimental constraints. One major challenge concerns an efficient integration between OA and pulse-echo US measurements using the same transducer array. A common approach toward the hybridization consists in using standard linear transducer arrays, which readily results in arc-type artifacts and distorted shapes in OA images due to the limited angular coverage. Deep learning methods have been proposed to mitigate limited-view artifacts in OA reconstructions by mapping artifactual to artifact-free (ground truth) images. However, acquisition of ground truth data with full angular coverage is not always possible, particularly when using handheld probes in a clinical setting. Deep learning methods operating in the image domain are then commonly based on networks trained on simulated data. This approach is yet incapable of transferring the learned features between two domains, which results in poor performance on experimental data. Here, we propose a signal domain adaptation network (SDAN) consisting of i) a domain adaptation network to reduce the domain gap between simulated and experimental signals and ii) a sides prediction network to complement the missing signals in limited-view OA datasets acquired from a human forearm by means of a handheld linear transducer array. The proposed method showed improved performance in reducing limited-view artifacts without the need for ground truth signals from full tomographic acquisitions.
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Affiliation(s)
| | - Berkan Lafci
- Institute for Biomedical Engineering, Department of Information Technology and Electrical Engineering, ETH Zurich, Switzerland; Institute of Pharmacology and Toxicology and Institute for Biomedical Engineering, Faculty of Medicine, University of Zurich, Switzerland
| | - Firat Ozdemir
- Swiss Data Science Center, ETH Zürich and EPFL, Switzerland
| | - Neda Davoudi
- Institute for Biomedical Engineering, Department of Information Technology and Electrical Engineering, ETH Zurich, Switzerland; Institute of Pharmacology and Toxicology and Institute for Biomedical Engineering, Faculty of Medicine, University of Zurich, Switzerland
| | - Xosé Luís Deán-Ben
- Institute for Biomedical Engineering, Department of Information Technology and Electrical Engineering, ETH Zurich, Switzerland; Institute of Pharmacology and Toxicology and Institute for Biomedical Engineering, Faculty of Medicine, University of Zurich, Switzerland
| | - Fernando Perez-Cruz
- Swiss Data Science Center, ETH Zürich and EPFL, Switzerland; Institute for Machine Learning, Department of Computer Science, ETH Zurich, Switzerland
| | - Daniel Razansky
- Institute for Biomedical Engineering, Department of Information Technology and Electrical Engineering, ETH Zurich, Switzerland; Institute of Pharmacology and Toxicology and Institute for Biomedical Engineering, Faculty of Medicine, University of Zurich, Switzerland.
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Silemek B, Seifert F, Petzold J, Brühl R, Ittermann B, Winter L. Wirelessly interfacing sensor-equipped implants and MR scanners for improved safety and imaging. Magn Reson Med 2023; 90:2608-2626. [PMID: 37533167 DOI: 10.1002/mrm.29818] [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: 02/07/2023] [Revised: 07/12/2023] [Accepted: 07/13/2023] [Indexed: 08/04/2023]
Abstract
PURPOSE To investigate a novel reduced RF heating method for imaging in the presence of active implanted medical devices (AIMDs) which employs a sensor-equipped implant that provides wireless feedback. METHODS The implant, consisting of a generator case and a lead, measures RF-inducedE $$ E $$ -fields at the implant tip using a simple sensor in the generator case and transmits these values wirelessly to the MR scanner. Based on the sensor signal alone, parallel transmission (pTx) excitation vectors were calculated to suppress tip heating and maintain image quality. A sensor-based imaging metric was introduced to assess the image quality. The methodology was studied at 7T in testbed experiments, and at a 3T scanner in an ASTM phantom containing AIMDs instrumented with six realistic deep brain stimulation (DBS) lead configurations adapted from patients. RESULTS The implant successfully measured RF-inducedE $$ E $$ -fields (Pearson correlation coefficient squared [R2 ] = 0.93) and temperature rises (R2 = 0.95) at the implant tip. The implant acquired the relevant data needed to calculate the pTx excitation vectors and transmitted them wirelessly to the MR scanner within a single shot RF sequence (<60 ms). Temperature rises for six realistic DBS lead configurations were reduced to 0.03-0.14 K for heating suppression modes compared to 0.52-3.33 K for the worst-case heating, while imaging quality remained comparable (five of six lead imaging scores were ≥0.80/1.00) to conventional circular polarization (CP) images. CONCLUSION Implants with sensors that can communicate with an MR scanner can substantially improve safety for patients in a fast and automated manner, easing the current burden for MR personnel.
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Affiliation(s)
- Berk Silemek
- Physikalisch-Technische Bundesanstalt (PTB), Braunschweig and Berlin, Germany
| | - Frank Seifert
- Physikalisch-Technische Bundesanstalt (PTB), Braunschweig and Berlin, Germany
| | - Johannes Petzold
- Physikalisch-Technische Bundesanstalt (PTB), Braunschweig and Berlin, Germany
| | - Rüdiger Brühl
- Physikalisch-Technische Bundesanstalt (PTB), Braunschweig and Berlin, Germany
| | - Bernd Ittermann
- Physikalisch-Technische Bundesanstalt (PTB), Braunschweig and Berlin, Germany
| | - Lukas Winter
- Physikalisch-Technische Bundesanstalt (PTB), Braunschweig and Berlin, Germany
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Hellwig D, Hellwig NC, Boehner S, Fuchs T, Fischer R, Schmidt D. Artificial Intelligence and Deep Learning for Advancing PET Image Reconstruction: State-of-the-Art and Future Directions. Nuklearmedizin 2023; 62:334-342. [PMID: 37995706 PMCID: PMC10689088 DOI: 10.1055/a-2198-0358] [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: 08/28/2023] [Accepted: 10/12/2023] [Indexed: 11/25/2023]
Abstract
Positron emission tomography (PET) is vital for diagnosing diseases and monitoring treatments. Conventional image reconstruction (IR) techniques like filtered backprojection and iterative algorithms are powerful but face limitations. PET IR can be seen as an image-to-image translation. Artificial intelligence (AI) and deep learning (DL) using multilayer neural networks enable a new approach to this computer vision task. This review aims to provide mutual understanding for nuclear medicine professionals and AI researchers. We outline fundamentals of PET imaging as well as state-of-the-art in AI-based PET IR with its typical algorithms and DL architectures. Advances improve resolution and contrast recovery, reduce noise, and remove artifacts via inferred attenuation and scatter correction, sinogram inpainting, denoising, and super-resolution refinement. Kernel-priors support list-mode reconstruction, motion correction, and parametric imaging. Hybrid approaches combine AI with conventional IR. Challenges of AI-assisted PET IR include availability of training data, cross-scanner compatibility, and the risk of hallucinated lesions. The need for rigorous evaluations, including quantitative phantom validation and visual comparison of diagnostic accuracy against conventional IR, is highlighted along with regulatory issues. First approved AI-based applications are clinically available, and its impact is foreseeable. Emerging trends, such as the integration of multimodal imaging and the use of data from previous imaging visits, highlight future potentials. Continued collaborative research promises significant improvements in image quality, quantitative accuracy, and diagnostic performance, ultimately leading to the integration of AI-based IR into routine PET imaging protocols.
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Affiliation(s)
- Dirk Hellwig
- Department of Nuclear Medicine, University Hospital Regensburg, Regensburg, Germany
- Partner Site Regensburg, Bavarian Center for Cancer Research (BZKF), Regensburg, Germany
- Medical Data Integration Center (MEDIZUKR), University Hospital Regensburg, Regensburg, Germany
| | - Nils Constantin Hellwig
- Department of Nuclear Medicine, University Hospital Regensburg, Regensburg, Germany
- Medical Data Integration Center (MEDIZUKR), University Hospital Regensburg, Regensburg, Germany
| | - Steven Boehner
- Department of Nuclear Medicine, University Hospital Regensburg, Regensburg, Germany
- Partner Site Regensburg, Bavarian Center for Cancer Research (BZKF), Regensburg, Germany
- Medical Data Integration Center (MEDIZUKR), University Hospital Regensburg, Regensburg, Germany
| | - Timo Fuchs
- Department of Nuclear Medicine, University Hospital Regensburg, Regensburg, Germany
- Partner Site Regensburg, Bavarian Center for Cancer Research (BZKF), Regensburg, Germany
- Medical Data Integration Center (MEDIZUKR), University Hospital Regensburg, Regensburg, Germany
| | - Regina Fischer
- Department of Nuclear Medicine, University Hospital Regensburg, Regensburg, Germany
- Partner Site Regensburg, Bavarian Center for Cancer Research (BZKF), Regensburg, Germany
- Medical Data Integration Center (MEDIZUKR), University Hospital Regensburg, Regensburg, Germany
| | - Daniel Schmidt
- Department of Nuclear Medicine, University Hospital Regensburg, Regensburg, Germany
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Jiang F, Bhusal B, Nguyen B, Monge M, Webster G, Kim D, Bonmassar G, Popsecu AR, Golestanirad L. Modifying the trajectory of epicardial leads can substantially reduce MRI-induced RF heating in pediatric patients with a cardiac implantable electronic device at 1.5T. Magn Reson Med 2023; 90:2510-2523. [PMID: 37526134 PMCID: PMC10863853 DOI: 10.1002/mrm.29776] [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: 07/05/2022] [Revised: 05/12/2023] [Accepted: 06/06/2023] [Indexed: 08/02/2023]
Abstract
PURPOSE After epicardial cardiac implantable electronic devices are implanted in pediatric patients, they become ineligible to receive MRI exams due to an elevated risk of RF heating. We investigated whether simple modifications in the trajectories of epicardial leads could substantially and reliably reduce RF heating during MRI at 1.5 T, with benefits extending to abandoned leads. METHODS Electromagnetic simulations were performed to assess RF heating of two common 35-cm epicardial lead trajectories exhibiting different degrees of coupling with MRI incident electric fields. Experiments in anthropomorphic phantoms implanted with commercial cardiac implantable electronic devices confirmed the findings. Both electromagnetic simulations and experimental measurements were performed using head-first and feet-first positioning and various landmarks. Transfer function approach was used to assess the performance of suggested modifications in realistic body models. RESULTS Simulations (head-first, chest landmark) of a 35-cm epicardial lead with a trajectory where the excess length of the lead was looped and placed on the inferior surface of the heart showed an 87-fold reduction in the 0.1 g-averaged specific absorption rate compared with the lead where the excess length was looped on the anterior surface. Repeated experiments with a commercial epicardial device confirmed this. For fully implanted systems following low-specific absorption rate trajectories, there was a 16-fold reduction in the average temperature rise and a 28-fold reduction for abandoned leads. The transfer function method predicted a 7-fold reduction in the RF heating in 336 realistic scenarios. CONCLUSION Surgical modification of epicardial lead trajectory can substantially reduce RF heating at 1.5 T, with benefits extending to abandoned leads.
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Affiliation(s)
- Fuchang Jiang
- Department of Biomedical Engineering, McCormick School of Engineering, Northwestern University, Evanston, Illinois, USA
| | - Bhumi Bhusal
- Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
| | - Bach Nguyen
- Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
| | - Michael Monge
- Division of Cardiovascular-Thoracic Surgery, Ann & Robert H. Lurie Children’s Hospital of Chicago, Box 22, 225 E. Chicago Ave, Chicago, Illinois, 60611, USA
| | - Gregory Webster
- Division of Cardiology, Ann and Robert H. Lurie Children’s Hospital of Chicago, Northwestern University Feinberg School of Medicine, 225 East Chicago Avenue, Box 21, Chicago, IL, 60611, USA
| | - Daniel Kim
- Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
| | - Giorgio Bonmassar
- A. A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Boston, MA, USA
| | - Andrada R. Popsecu
- Division of Medical Imaging, Ann & Robert H. Lurie Children’s Hospital of Chicago, Chicago, IL, USA
| | - Laleh Golestanirad
- Department of Biomedical Engineering, McCormick School of Engineering, Northwestern University, Evanston, Illinois, USA
- Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
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Sadeghi-Tarakameh A, DelaBarre L, Zulkarnain NIH, Harel N, Eryaman Y. Implant-friendly MRI of deep brain stimulation electrodes at 7 T. Magn Reson Med 2023; 90:2627-2642. [PMID: 37533196 PMCID: PMC10543551 DOI: 10.1002/mrm.29825] [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: 03/03/2023] [Revised: 07/18/2023] [Accepted: 07/19/2023] [Indexed: 08/04/2023]
Abstract
PURPOSE The purpose of this study is to present a strategy to calculate the implant-friendly (IF) excitation modes-which mitigate the RF heating at the contacts of deep brain stimulation (DBS) electrodes-of multichannel RF coils at 7 T. METHODS An induced RF current on an implantable electrode generates a scattered magnetic field whose left-handed circularly polarizing component (B 1 + $$ B{1}^{+} $$ ) is approximated using aB 1 + $$ B{1}^{+} $$ -mapping technique and subsequently used as a gauge for the electrode's induced current. Using this approach, the relative induced currents resulting from each channel of a multichannel RF coil on the DBS electrode were calculated. The IF modes of the corresponding multichannel coil were determined by calculating the null space of the relative induced currents. The proposed strategy was tested and validated for unilateral and bilateral commercial DBS electrodes (directional lead; Infinity DBS system, Abbott Laboratories) placed inside a uniform phantom by performing heating and imaging studies on a 7T MRI scanner using a 16-channel transceive RF coil. RESULTS Neither individual IF modes nor shim solutions obtained from IF modes induced significant temperature increase when used for a high-power turbo spin-echo sequence. In contrast, shimming with the scanner's toolbox (i.e., based on per-channelB 1 + $$ B{1}^{+} $$ fields) resulted in a more than 2°C temperature increase for the same amount of input power. CONCLUSION A strategy for calculating the IF modes of a multichannel RF coil is presented. This strategy was validated using a 16-channel RF coil at 7 T for unilateral and bilateral commercial DBS electrodes inside a uniform phantom.
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Affiliation(s)
| | - Lance DelaBarre
- Center for Magnetic Resonance Research (CMRR), University of Minnesota, Minneapolis, Minnesota, USA
| | | | - Noam Harel
- Center for Magnetic Resonance Research (CMRR), University of Minnesota, Minneapolis, Minnesota, USA
| | - Yigitcan Eryaman
- Center for Magnetic Resonance Research (CMRR), University of Minnesota, Minneapolis, Minnesota, USA
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Wang J, Ji B, Lei Y, Liu T, Mao H, Yang X. Denoising magnetic resonance spectroscopy (MRS) data using stacked autoencoder for improving signal-to-noise ratio and speed of MRS. Med Phys 2023; 50:7955-7966. [PMID: 37947479 PMCID: PMC10872746 DOI: 10.1002/mp.16831] [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: 03/30/2023] [Revised: 10/05/2023] [Accepted: 10/25/2023] [Indexed: 11/12/2023] Open
Abstract
BACKGROUND While magnetic resonance imaging (MRI) provides high resolution anatomical images with sharp soft tissue contrast, magnetic resonance spectroscopy (MRS) enables non-invasive detection and measurement of biochemicals and metabolites. However, MRS has low signal-to-noise ratio (SNR) when concentrations of metabolites are in the range of millimolar. Standard approach of using a high number of signal averaging (NSA) to achieve sufficient SNR comes at the cost of a long acquisition time. PURPOSE We propose to use deep-learning approaches to denoise MRS data without increasing NSA. This method has potential to reduce the acquisition time as well as improve SNR and quality of spectra, which could enhance the diagnostic value and broaden the clinical applications of MRS. METHODS The study was conducted using data collected from the brain spectroscopy phantom and human subjects. We utilized a stack auto-encoder (SAE) network to train deep learning models for denoising low NSA data (NSA = 1, 2, 4, 8, and 16) randomly truncated from high SNR data collected with high NSA (NSA = 192), which were also used to obtain the ground truth. We applied both self-supervised and fully-supervised training approaches and compared their performance of denoising low NSA data based on improvement in SNR. To prevent overfitting, the SAE network was trained in a patch-based manner. We then tested the denoising methods on noise-containing data collected from the phantom and human subjects, including data from brain tumor patients. We evaluated their performance by comparing the SNR levels and mean squared errors (MSEs) calculated for the whole spectra against high SNR "ground truth", as well as the value of chemical shift of N-acetyl-aspartate (NAA) before and after denoising. RESULTS With the SAE model, the SNR of low NSA data (NSA = 1) obtained from the phantom increased by 28.5% and the MSE decreased by 42.9%. For low NSA data of the human parietal and temporal lobes, the SNR increased by 32.9% and the MSE decreased by 63.1%. In all cases, the chemical shift of NAA in the denoised spectra closely matched with the high SNR spectra without significant distortion to the spectra after denoising. Furthermore, the denoising performance of the SAE model was more effective in denoising spectra with higher noise levels. CONCLUSIONS The reported SAE denoising method is a model-free approach to enhance the SNR of MRS data collected with low NSA. With the denoising capability, it is possible to acquire MRS data with a few NSA, shortening the scan time while maintaining adequate spectroscopic information for detecting and quantifying the metabolites of interest. This approach has the potential to improve the efficiency and effectiveness of clinical MRS data acquisition by reducing the scan time and increasing the quality of spectroscopic data.
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Affiliation(s)
- Jing Wang
- Department of Radiation Oncology and Winship Cancer Institute, Emory University, Atlanta, GA 30322, USA
| | - Bing Ji
- Department of Radiology and Imaging Science and Winship Cancer Institute, Emory University, Atlanta, GA 30322, USA
| | - Yang Lei
- Department of Radiation Oncology and Winship Cancer Institute, Emory University, Atlanta, GA 30322, USA
| | - Tian Liu
- Department of Radiation Oncology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Hui Mao
- Department of Radiology and Imaging Science and Winship Cancer Institute, Emory University, Atlanta, GA 30322, USA
| | - Xiaofeng Yang
- Department of Radiation Oncology and Winship Cancer Institute, Emory University, Atlanta, GA 30322, USA
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Rios NL, Gilbert KM, Papp D, Cereza G, Foias A, Rangaprakash D, May MW, Guerin B, Wald LL, Keil B, Stockmann JP, Barry RL, Cohen-Adad J. An 8-channel Tx dipole and 20-channel Rx loop coil array for MRI of the cervical spinal cord at 7 Tesla. NMR Biomed 2023; 36:e5002. [PMID: 37439129 PMCID: PMC10733907 DOI: 10.1002/nbm.5002] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 05/10/2023] [Accepted: 06/15/2023] [Indexed: 07/14/2023]
Abstract
The quality of cervical spinal cord images can be improved by the use of tailored radiofrequency (RF) coil solutions for ultrahigh field imaging; however, very few commercial and research 7-T RF coils currently exist for the spinal cord, and in particular, those with parallel transmission (pTx) capabilities. This work presents the design, testing, and validation of a pTx/Rx coil for the human neck and cervical/upper thoracic spinal cord. The pTx portion is composed of eight dipoles to ensure high homogeneity over this large region of the spinal cord. The Rx portion is made up of twenty semiadaptable overlapping loops to produce high signal-to-noise ratio (SNR) across the patient population. The coil housing is designed to facilitate patient positioning and comfort, while also being tight fitting to ensure high sensitivity. We demonstrate RF shimming capabilities to optimize B1 + uniformity, power efficiency, and/or specific absorption rate efficiency. B1 + homogeneity, SNR, and g-factor were evaluated in adult volunteers and demonstrated excellent performance from the occipital lobe down to the T4-T5 level. We compared the proposed coil with two state-of-the-art head and head/neck coils, confirming its superiority in the cervical and upper thoracic regions of the spinal cord. This coil solution therefore provides a convincing platform for producing the high image quality necessary for clinical and research scanning of the upper spinal cord.
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Affiliation(s)
- Nibardo Lopez Rios
- NeuroPoly Lab, Institute of Biomedical Engineering, Polytechnique Montréal, Montréal, QC, Canada
| | - Kyle M. Gilbert
- Centre for Functional and Metabolic Mapping, The University of Western Ontario, London, ON, Canada
| | - Daniel Papp
- NeuroPoly Lab, Institute of Biomedical Engineering, Polytechnique Montréal, Montréal, QC, Canada
| | - Gaspard Cereza
- NeuroPoly Lab, Institute of Biomedical Engineering, Polytechnique Montréal, Montréal, QC, Canada
| | - Alexandru Foias
- NeuroPoly Lab, Institute of Biomedical Engineering, Polytechnique Montréal, Montréal, QC, Canada
| | - D. Rangaprakash
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Markus W. May
- Erwin L. Hahn Institute for Magnetic Resonance Imaging, University of Duisburg-Essen, Essen, Germany
- High Field and Hybrid MR Imaging, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Bastien Guerin
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Lawrence L. Wald
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, USA
- Harvard Medical School, Boston, MA, USA
- Harvard-Massachusetts Institute of Technology Health Sciences & Technology, Cambridge, MA, USA
| | - Boris Keil
- Institute of Medical Physics and Radiation Protection, University of Applied Sciences Mittelhessen, Giessen, Germany
- Department of Diagnostic and Interventional Radiology, University Hospital Marburg, Philipps University of Marburg, Marburg, Germany
| | - Jason P. Stockmann
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Robert L. Barry
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, USA
- Harvard Medical School, Boston, MA, USA
- Harvard-Massachusetts Institute of Technology Health Sciences & Technology, Cambridge, MA, USA
| | - Julien Cohen-Adad
- NeuroPoly Lab, Institute of Biomedical Engineering, Polytechnique Montréal, Montréal, QC, Canada
- Functional Neuroimaging Unit, CRIUGM, Université de Montréal, Montreal, QC, Canada
- Mila – Quebec AI Institute, Montreal, QC, Canada
- Centre de recherche du CHU Sainte-Justine, Université de Montréal, Montréal, QC, Canada
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Kaźmierski R. Brain injury mobile diagnostic system: Applications in civilian medical service and on the battlefield-General concept and medical aspects. J Clin Ultrasound 2023; 51:1598-1606. [PMID: 37702254 DOI: 10.1002/jcu.23545] [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] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 08/07/2023] [Accepted: 08/10/2023] [Indexed: 09/14/2023]
Abstract
To present the concept of a portable ultrasound tomography device for diagnosing traumatic and vascular brain lesions. The device consisting of multiple transcranial ultrasound probes placed on the surface of the head, specifically but not exclusively in natural acoustic windows. An integral part of the mobile diagnostic system (MDS) is a decision support system based on artificial intelligence algorithms utilizing information from: head images, laboratory data, and assessment of the patient's clinical condition. The MDS can significantly reduce the time from stroke onset to rtPA therapy in civilian medical services and support therapeutic and evacuation strategies in instances of brain and skull trauma on the battlefield.
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Affiliation(s)
- Radosław Kaźmierski
- Department of Neurology, Collegium Medicum, University of Zielona Góra, Zielona Góra, Poland
- Department for Neurology, Poznan University of Medical Sciences, Poznan, Poland
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Andersen MS, Kofoed MS, Paludan-Müller AS, Pedersen CB, Mathiesen T, Mawrin C, Wirenfeldt M, Kristensen BW, Olsen BB, Halle B, Poulsen FR. Meningioma animal models: a systematic review and meta-analysis. J Transl Med 2023; 21:764. [PMID: 37898750 PMCID: PMC10612271 DOI: 10.1186/s12967-023-04620-7] [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: 07/25/2023] [Accepted: 10/11/2023] [Indexed: 10/30/2023] Open
Abstract
BACKGROUND Animal models are widely used to study pathological processes and drug (side) effects in a controlled environment. There is a wide variety of methods available for establishing animal models depending on the research question. Commonly used methods in tumor research include xenografting cells (established/commercially available or primary patient-derived) or whole tumor pieces either orthotopically or heterotopically and the more recent genetically engineered models-each type with their own advantages and disadvantages. The current systematic review aimed to investigate the meningioma model types used, perform a meta-analysis on tumor take rate (TTR), and perform critical appraisal of the included studies. The study also aimed to assess reproducibility, reliability, means of validation and verification of models, alongside pros and cons and uses of the model types. METHODS We searched Medline, Embase, and Web of Science for all in vivo meningioma models. The primary outcome was tumor take rate. Meta-analysis was performed on tumor take rate followed by subgroup analyses on the number of cells and duration of incubation. The validity of the tumor models was assessed qualitatively. We performed critical appraisal of the methodological quality and quality of reporting for all included studies. RESULTS We included 114 unique records (78 using established cell line models (ECLM), 21 using primary patient-derived tumor models (PTM), 10 using genetically engineered models (GEM), and 11 using uncategorized models). TTRs for ECLM were 94% (95% CI 92-96) for orthotopic and 95% (93-96) for heterotopic. PTM showed lower TTRs [orthotopic 53% (33-72) and heterotopic 82% (73-89)] and finally GEM revealed a TTR of 34% (26-43). CONCLUSION This systematic review shows high consistent TTRs in established cell line models and varying TTRs in primary patient-derived models and genetically engineered models. However, we identified several issues regarding the quality of reporting and the methodological approach that reduce the validity, transparency, and reproducibility of studies and suggest a high risk of publication bias. Finally, each tumor model type has specific roles in research based on their advantages (and disadvantages). SYSTEMATIC REVIEW REGISTRATION PROSPERO-ID CRD42022308833.
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Affiliation(s)
- Mikkel Schou Andersen
- Department of Neurosurgery, Odense University Hospital, Odense, Denmark.
- BRIDGE (Brain Research - Inter Disciplinary Guided Excellence), University of Southern Denmark, Odense, Denmark.
- Department of Clinical Research, University of Southern Denmark, Odense, Denmark.
| | - Mikkel Seremet Kofoed
- Department of Neurosurgery, Odense University Hospital, Odense, Denmark
- BRIDGE (Brain Research - Inter Disciplinary Guided Excellence), University of Southern Denmark, Odense, Denmark
- Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Asger Sand Paludan-Müller
- Nordic Cochrane Centre, Rigshospitalet, Copenhagen University, Copenhagen, Denmark
- Centre for Evidence-Based Medicine Odense (CEBMO) and NHTA: Market Access & Health Economics Consultancy, Copenhagen, Denmark
| | - Christian Bonde Pedersen
- Department of Neurosurgery, Odense University Hospital, Odense, Denmark
- BRIDGE (Brain Research - Inter Disciplinary Guided Excellence), University of Southern Denmark, Odense, Denmark
- Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Tiit Mathiesen
- Department of Neurosurgery, Rigshospitalet, Copenhagen University, Copenhagen, Denmark
| | - Christian Mawrin
- Department of Neuropathology, Otto-Von-Guericke University, Magdeburg, Germany
| | - Martin Wirenfeldt
- Department of Pathology and Molecular Biology, Hospital South West Jutland, Esbjerg, Denmark
- Department of Regional Health Research, University of Southern, Odense, Denmark
| | | | - Birgitte Brinkmann Olsen
- Clinical Physiology and Nuclear Medicine, Odense University Hospital, Odense, Denmark
- Department of Surgical Pathology, Zealand University Hospital, Roskilde, Denmark
| | - Bo Halle
- Department of Neurosurgery, Odense University Hospital, Odense, Denmark
- BRIDGE (Brain Research - Inter Disciplinary Guided Excellence), University of Southern Denmark, Odense, Denmark
- Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Frantz Rom Poulsen
- Department of Neurosurgery, Odense University Hospital, Odense, Denmark
- BRIDGE (Brain Research - Inter Disciplinary Guided Excellence), University of Southern Denmark, Odense, Denmark
- Department of Clinical Research, University of Southern Denmark, Odense, Denmark
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Grutman T, Ilovitsh T. Dense speed-of-sound shift imaging for ultrasonic thermometry. Phys Med Biol 2023; 68:215004. [PMID: 37774710 DOI: 10.1088/1361-6560/acfec3] [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: 06/30/2023] [Accepted: 09/29/2023] [Indexed: 10/01/2023]
Abstract
Objective. Develop a dense algorithm for calculating the speed-of-sound shift between consecutive acoustic acquisitions as a noninvasive means to evaluating temperature change during thermal ablation.Methods. An algorithm for dense speed-of-sound shift imaging (DSI) was developed to simultaneously incorporate information from the entire field of view using a combination of dense optical flow and inverse problem regularization, thus speeding up the calculation and introducing spatial agreement between pixels natively. Thermal ablation monitoring consisted of two main steps: pixel shift tracking using Farneback optical flow, and mathematical modeling of the relationship between the pixel displacement and temperature change as an inverse problem to find the speed-of-sound shift. A calibration constant translates from speed-of-sound shift to temperature change. The method performance was tested inex vivosamples and compared to standard thermal strain imaging (TSI) methods.Main results. Thermal ablation at a frequency of 2 MHz was applied to an agarose phantom that created a speed-of-sound shift measured by an L12-5 imaging transducer. A focal spot was reconstructed by solving the inverse problem. Next, a thermocouple measured the temperature rise during thermal ablation ofex vivochicken breast to calibrate the setup. Temperature changes between 3 °C and 15 °C was measured with high thermometry precision of less than 2 °C error for temperature changes as low as 8 °C. The DSI method outperformed standard TSI in both spatial coherence and runtime in high-intensity focused ultrasound-induced hyperthermia.Significance. Dense ultrasonic speed-of-sound shift imaging can successfully monitor the speed-of-sound shift introduced by thermal ablation. This technique is faster and more robust than current methods, and therefore can be used as a noninvasive, real time and cost-effective thermometry method, with high clinical applicability.
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Affiliation(s)
- Tal Grutman
- Department of Biomedical Engineering, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Tali Ilovitsh
- Department of Biomedical Engineering, Tel Aviv University, Tel Aviv 6997801, Israel
- The Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 6997801, Israel
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Arias-Valcayo F, Galve P, Herraiz JL, Vaquero JJ, Desco M, Udías JM. Reconstruction of multi-animal PET acquisitions with anisotropically variant PSF. Biomed Phys Eng Express 2023; 9:065018. [PMID: 37703847 DOI: 10.1088/2057-1976/acf936] [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: 04/19/2023] [Accepted: 09/13/2023] [Indexed: 09/15/2023]
Abstract
Among other factors such as random, attenuation and scatter corrections, uniform spatial resolution is key to performing accurate quantitative studies in Positron emission tomography (PET). Particularly in preclinical PET studies involving simultaneous acquisition of multiple animals, the degradation of image resolution due to the depth of interaction (DOI) effect far from the center of the Field of View (FOV) becomes a significant concern. In this work, we incorporated a spatially-variant resolution model into a real time iterative reconstruction code to obtain accurate images of multi-animal acquisition. We estimated the spatially variant point spread function (SV-PSF) across the FOV using measurements and Monte Carlo (MC) simulations. The SV-PSF obtained was implemented in a GPU-based Ordered subset expectation maximization (OSEM) reconstruction code, which includes scatter, attenuation and random corrections. The method was evaluated with acquisitions from two preclinical PET/CT scanners of the SEDECAL Argus family: a Derenzo phantom placed 2 cm off center in the 4R-SuperArgus, and a multi-animal study with 4 mice in the 6R-SuperArgus. The SV-PSF reconstructions showed uniform spatial resolution without significant increase in reconstruction time, with superior image quality compared to the uniform PSF model.
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Affiliation(s)
- F Arias-Valcayo
- Grupo de Física Nuclear, EMFTEL & IPARCOS, Universidad Complutense de Madrid, CEI Moncloa, Madrid, Spain
| | - P Galve
- Grupo de Física Nuclear, EMFTEL & IPARCOS, Universidad Complutense de Madrid, CEI Moncloa, Madrid, Spain
- Instituto de Investigación Del Hospital Clínico San Carlos (IdISSC), Ciudad Universitaria, Madrid, Spain
- Universite Paris Cite, PARCC, INSERM 56, rue Leblanc Paris, Île-de-France, France
| | - Joaquín L Herraiz
- Grupo de Física Nuclear, EMFTEL & IPARCOS, Universidad Complutense de Madrid, CEI Moncloa, Madrid, Spain
- Instituto de Investigación Del Hospital Clínico San Carlos (IdISSC), Ciudad Universitaria, Madrid, Spain
| | - J J Vaquero
- Departmento de Bioingeniería, Universidad Carlos III de Madrid, Madrid, Spain
- Instituto de Investigación Sanitaria Gregorio Maranón, Madrid, Spain
| | - M Desco
- Departmento de Bioingeniería, Universidad Carlos III de Madrid, Madrid, Spain
- Instituto de Investigación Sanitaria Gregorio Maranón, Madrid, Spain
- Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain
- CIBER de Salud Mental, Instituto de Salud Carlos III, Madrid, Spain
| | - J M Udías
- Grupo de Física Nuclear, EMFTEL & IPARCOS, Universidad Complutense de Madrid, CEI Moncloa, Madrid, Spain
- Instituto de Investigación Del Hospital Clínico San Carlos (IdISSC), Ciudad Universitaria, Madrid, Spain
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Huda K, Lawrence DJ, Thompson W, Lindsey SH, Bayer CL. In vivo noninvasive systemic myography of acute systemic vasoactivity in female pregnant mice. Nat Commun 2023; 14:6286. [PMID: 37813833 PMCID: PMC10562381 DOI: 10.1038/s41467-023-42041-8] [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: 02/03/2023] [Accepted: 09/28/2023] [Indexed: 10/11/2023] Open
Abstract
Altered vasoactivity is a major characteristic of cardiovascular and oncological diseases, and many therapies are therefore targeted to the vasculature. Therapeutics which are selective for the diseased vasculature are ideal, but whole-body selectivity of a therapeutic is challenging to assess in practice. Vessel myography is used to determine the functional mechanisms and evaluate pharmacological responses of vascularly-targeted therapeutics. However, myography can only be performed on ex vivo sections of individual arteries. We have developed methods for implementation of spherical-view photoacoustic tomography for non-invasive and in vivo myography. Using photoacoustic tomography, we demonstrate the measurement of acute vascular reactivity in the systemic vasculature and the placenta of female pregnant mice in response to two vasodilators. Photoacoustic tomography simultaneously captures the significant acute vasodilation of major arteries and detects selective vasoactivity of the maternal-fetal vasculature. Photoacoustic tomography has the potential to provide invaluable preclinical information on vascular response that cannot be obtained by other established methods.
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Affiliation(s)
- Kristie Huda
- Department of Biomedical Engineering, Tulane University, New Orleans, LA, USA
| | - Dylan J Lawrence
- Department of Biomedical Engineering, Tulane University, New Orleans, LA, USA
- Photosound Technologies Inc., Houston, TX, USA
| | | | - Sarah H Lindsey
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, LA, USA
| | - Carolyn L Bayer
- Department of Biomedical Engineering, Tulane University, New Orleans, LA, USA.
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Carroll L, Enger SA. M-TAG: A modular teaching-aid for Geant4. Heliyon 2023; 9:e20229. [PMID: 37810860 PMCID: PMC10556609 DOI: 10.1016/j.heliyon.2023.e20229] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 09/13/2023] [Accepted: 09/14/2023] [Indexed: 10/10/2023] Open
Abstract
Geant4 is a versatile Monte Carlo radiation transport simulation toolkit with a steep learning curve. This work introduces a user-code called M-TAG (Modular Radiation Teaching-Aid for Geant4), built on top of Geant4. M-TAG is designed to help gradually introduce the Geant4 toolkit to new users. The goal of Geant4 is to record quantities from the simulated radiation as it is transported through geometries. M-TAG simplifies the inclusion of new geometric elements and detector components in the simulation by including new classes. M-TAG also provides basic validated examples for some common detector development tasks. Geant4 intercom modules, called messenger classes, manage these classes. To validate M-TAG, simulations were performed to calculate the range of positrons in water. One hundred million decays at the center of a water-filled sphere with a radius of 1 m were allowed for fluorine-18, carbon-11, oxygen-15 and gallium-68. These results were compared to literature values. An inexperienced Geant4 user was tasked with creating a simulation model for a plastic scintillator-based detector and conducting basic tests to assess the effectiveness of M-TAG as a teaching tool. The simulation involved calculating the dose to the detector's sensitive volume using a 2x2 cm planar monoenergetic photon source spanning energies from 20 to 100 keV. One billion particles were simulated twice: once with the actual detector geometry and once with the sensitive volume replaced by water. The validity of M-TAG was also verified by computing dose ratios and comparing them with mass-attenuation ratios obtained from NIST XCOM data sets. The mean positron travel distances were within the distribution of literature values. Simulated positron energy spectra means were within 1.8% of literature means. Simulated dose ratios agreed with literature values within uncertainties. We have developed and verified a modular Geant4 teaching aid called M-TAG. It was used to introduce a new user to Geant4, who used it to perform further validation simulations.
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Affiliation(s)
- Liam Carroll
- Medical Physics Unit, Department of Oncology, Faculty of Medicine, McGill University, Montreal, Quebec, Canada
- Lady Davis Institute for Medical Research, Jewish General Hospital, Montreal, QC, H3T 1E2, Canada
| | - Shirin A. Enger
- Medical Physics Unit, Department of Oncology, Faculty of Medicine, McGill University, Montreal, Quebec, Canada
- Lady Davis Institute for Medical Research, Jewish General Hospital, Montreal, QC, H3T 1E2, Canada
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Li F, Villa U, Duric N, Anastasio MA. A Forward Model Incorporating Elevation-Focused Transducer Properties for 3-D Full-Waveform Inversion in Ultrasound Computed Tomography. IEEE Trans Ultrason Ferroelectr Freq Control 2023; 70:1339-1354. [PMID: 37682648 PMCID: PMC10775680 DOI: 10.1109/tuffc.2023.3313549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/10/2023]
Abstract
Ultrasound computed tomography (USCT) is an emerging medical imaging modality that holds great promise for improving human health. Full-waveform inversion (FWI)-based image reconstruction methods account for the relevant wave physics to produce high spatial resolution images of the acoustic properties of the breast tissues. A practical USCT design employs a circular ring-array comprised of elevation-focused ultrasonic transducers, and volumetric imaging is achieved by translating the ring-array orthogonally to the imaging plane. In commonly deployed slice-by-slice (SBS) reconstruction approaches, the 3-D volume is reconstructed by stacking together 2-D images reconstructed for each position of the ring-array. A limitation of the SBS reconstruction approach is that it does not account for 3-D wave propagation physics and the focusing properties of the transducers, which can result in significant image artifacts and inaccuracies. To perform 3-D image reconstruction when elevation-focused transducers are employed, a numerical description of the focusing properties of the transducers should be included in the forward model. To address this, a 3-D computational model of an elevation-focused transducer is developed to enable 3-D FWI-based reconstruction methods to be deployed in ring-array-based USCT. The focusing is achieved by applying a spatially varying temporal delay to the ultrasound pulse (emitter mode) and recorded signal (receiver mode). The proposed numerical transducer model is quantitatively validated and employed in computer simulation studies that demonstrate its use in image reconstruction for ring-array USCT.
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Liu Y, Li A, Cheng R, Li B, Xie Q, Wang X, Qiu B, Chen X, Xiao P. A depth-of-interaction rebinning method based on both geometric and activity weights. Comput Methods Programs Biomed 2023; 240:107703. [PMID: 37531688 DOI: 10.1016/j.cmpb.2023.107703] [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] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 06/29/2023] [Accepted: 06/30/2023] [Indexed: 08/04/2023]
Abstract
BACKGROUND AND OBJECTIVE For positron emission tomography (PET) scanners with depth-of-interaction (DOI) measurement, the DOI rebinning method that utilizes DOI information to process the projection data is critical to image quality. Current DOI rebinning methods map coincidence events onto the rebinned sinogram based on the correlation of lines of response (LOR). This study aims to incorporate prior radioactivity distribution of the imaging object into DOI rebinning to obtain better image quality. METHODS A DOI rebinning method based on both geometric and activity weights was proposed to assign coincidence events to the rebinned sinogram defined by a virtual ring. The geometric weights, representing the correlation between LORs, were calculated based on the areas of intersection. The activity weights, reflecting the activity distribution of the imaging object, were derived from the previous reconstructed image. RESULTS Monte Carlo simulation data from four phantoms, including the image quality phantom, Derenzo phantom, and two rat-like ROBY phantoms, was used to evaluate the proposed method. The recovery coefficient (RC), contrast recovery coefficient (CRC), structural similarity index measure (SSIM), and peak signal-to-noise ratio (PSNR) were used as image quality metrics. Compared to other DOI rebinning methods, the proposed method achieved the highest RC (maximum improvement of 32%) and CRC at the same noise level and was also optimal in terms of the SSIM and PSNR. Meanwhile, incorporating the prior activity distribution into DOI rebinning also improved the image reconstruction speed. CONCLUSIONS This work developed a new DOI rebinning method combining the correlation of LORs with the prior activity distribution, achieving relatively optimal image quality and reconstruction speed. Furthermore, it still needs to be evaluated on the actual equipment.
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Affiliation(s)
- Yu Liu
- School of Artificial Intelligence and Automation, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Ang Li
- College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Ran Cheng
- College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Bingxuan Li
- Institute of Artificial Intelligence, Hefei Comprehensive National Science Center, Hefei 230026, China
| | - Qingguo Xie
- College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China; Department of Electronic Engineering and Information Science, University of Science and Technology of China, Hefei 230026, China; Institute of Artificial Intelligence, Hefei Comprehensive National Science Center, Hefei 230026, China
| | - Xiaoping Wang
- School of Artificial Intelligence and Automation, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Bensheng Qiu
- Department of Electronic Engineering and Information Science, University of Science and Technology of China, Hefei 230026, China
| | - Xun Chen
- Department of Electronic Engineering and Information Science, University of Science and Technology of China, Hefei 230026, China
| | - Peng Xiao
- College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China; Department of Electronic Engineering and Information Science, University of Science and Technology of China, Hefei 230026, China; Institute of Artificial Intelligence, Hefei Comprehensive National Science Center, Hefei 230026, China.
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Ibáñez-Moragues M, Fernández-Barahona I, Santacruz R, Oteo M, Luján-Rodríguez VM, Muñoz-Hernando M, Magro N, Lagares JI, Romero E, España S, Espinosa-Rodríguez A, García-Díez M, Martínez-Nouvilas V, Sánchez-Tembleque V, Udías JM, Valladolid-Onecha V, Martín-Rey MÁ, Almeida-Cordon EI, Viñals i Onsès S, Pérez JM, Fraile LM, Herranz F, Morcillo MÁ. Zinc-Doped Iron Oxide Nanoparticles as a Proton-Activatable Agent for Dose Range Verification in Proton Therapy. Molecules 2023; 28:6874. [PMID: 37836718 PMCID: PMC10574368 DOI: 10.3390/molecules28196874] [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: 07/19/2023] [Revised: 09/13/2023] [Accepted: 09/26/2023] [Indexed: 10/15/2023] Open
Abstract
Proton therapy allows the treatment of specific areas and avoids the surrounding tissues. However, this technique has uncertainties in terms of the distal dose fall-off. A promising approach to studying the proton range is the use of nanoparticles as proton-activatable agents that produce detectable signals. For this, we developed an iron oxide nanoparticle doped with Zn (IONP@Zn-cit) with a hydrodynamic size of 10 nm and stability in serum. Cytotoxicity, defined as half of the surveillance, was 100 μg Zn/mL in the U251 cell line. The effect on clonogenic cell death was tested after X-ray irradiation, which suggested a radioprotective effect of these nanoparticles at low concentrations (1-10 μg Zn/mL). To evaluate the production of positron emitters and prompt-gamma signals, IONP@Zn-cit was irradiated with protons, obtaining prompt-gamma signals at the lowest measured concentration (10 mg Zn/mL). Finally, 67Ga-IONP@Zn-cit showed accumulation in the liver and spleen and an accumulation in the tumor tissue of 0.95% ID/g in a mouse model of U251 cells. These results suggest the possibility of using Zn nanoparticles as proton-activatable agents to verify the range by prompt gamma detection and face the challenges of prompt gamma detection in a specific biological situation, opening different avenues to go forward in this field.
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Affiliation(s)
- Marta Ibáñez-Moragues
- Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas CIEMAT, Medical Applications of Ionizing Radiation Unit, 28040 Madrid, Spain; (R.S.); (M.O.); (V.M.L.-R.); (N.M.); (J.I.L.); (E.R.); (J.M.P.)
| | - Irene Fernández-Barahona
- Facultad de Farmacia, Universidad Complutense de Madrid, 28040 Madrid, Spain;
- Instituto de Química Médica—Consejo Superior de Investigaciones Científicas IQM-CSIC, Nanomedicine and Molecular Imaging Group, 28006 Madrid, Spain; (M.M.-H.)
| | - Rocío Santacruz
- Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas CIEMAT, Medical Applications of Ionizing Radiation Unit, 28040 Madrid, Spain; (R.S.); (M.O.); (V.M.L.-R.); (N.M.); (J.I.L.); (E.R.); (J.M.P.)
| | - Marta Oteo
- Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas CIEMAT, Medical Applications of Ionizing Radiation Unit, 28040 Madrid, Spain; (R.S.); (M.O.); (V.M.L.-R.); (N.M.); (J.I.L.); (E.R.); (J.M.P.)
| | - Víctor M. Luján-Rodríguez
- Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas CIEMAT, Medical Applications of Ionizing Radiation Unit, 28040 Madrid, Spain; (R.S.); (M.O.); (V.M.L.-R.); (N.M.); (J.I.L.); (E.R.); (J.M.P.)
| | - María Muñoz-Hernando
- Instituto de Química Médica—Consejo Superior de Investigaciones Científicas IQM-CSIC, Nanomedicine and Molecular Imaging Group, 28006 Madrid, Spain; (M.M.-H.)
| | - Natalia Magro
- Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas CIEMAT, Medical Applications of Ionizing Radiation Unit, 28040 Madrid, Spain; (R.S.); (M.O.); (V.M.L.-R.); (N.M.); (J.I.L.); (E.R.); (J.M.P.)
| | - Juan I. Lagares
- Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas CIEMAT, Medical Applications of Ionizing Radiation Unit, 28040 Madrid, Spain; (R.S.); (M.O.); (V.M.L.-R.); (N.M.); (J.I.L.); (E.R.); (J.M.P.)
| | - Eduardo Romero
- Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas CIEMAT, Medical Applications of Ionizing Radiation Unit, 28040 Madrid, Spain; (R.S.); (M.O.); (V.M.L.-R.); (N.M.); (J.I.L.); (E.R.); (J.M.P.)
| | - Samuel España
- Nuclear Physics Group, Universidad Complutense de Madrid, IPARCOS &EMFTEL, CEI Moncloa, 28040 Madrid, Spain; (S.E.); (A.E.-R.); (M.G.-D.); (V.M.-N.); (V.S.-T.); (J.M.U.); (V.V.-O.); (L.M.F.)
- Instituto de Investigación del Hospital Clínico San Carlos (IdISSC), Ciudad Universitaria, 28040 Madrid, Spain
| | - Andrea Espinosa-Rodríguez
- Nuclear Physics Group, Universidad Complutense de Madrid, IPARCOS &EMFTEL, CEI Moncloa, 28040 Madrid, Spain; (S.E.); (A.E.-R.); (M.G.-D.); (V.M.-N.); (V.S.-T.); (J.M.U.); (V.V.-O.); (L.M.F.)
- Instituto de Investigación del Hospital Clínico San Carlos (IdISSC), Ciudad Universitaria, 28040 Madrid, Spain
| | - Miguel García-Díez
- Nuclear Physics Group, Universidad Complutense de Madrid, IPARCOS &EMFTEL, CEI Moncloa, 28040 Madrid, Spain; (S.E.); (A.E.-R.); (M.G.-D.); (V.M.-N.); (V.S.-T.); (J.M.U.); (V.V.-O.); (L.M.F.)
- Instituto de Investigación del Hospital Clínico San Carlos (IdISSC), Ciudad Universitaria, 28040 Madrid, Spain
| | - Víctor Martínez-Nouvilas
- Nuclear Physics Group, Universidad Complutense de Madrid, IPARCOS &EMFTEL, CEI Moncloa, 28040 Madrid, Spain; (S.E.); (A.E.-R.); (M.G.-D.); (V.M.-N.); (V.S.-T.); (J.M.U.); (V.V.-O.); (L.M.F.)
- Instituto de Investigación del Hospital Clínico San Carlos (IdISSC), Ciudad Universitaria, 28040 Madrid, Spain
| | - Víctor Sánchez-Tembleque
- Nuclear Physics Group, Universidad Complutense de Madrid, IPARCOS &EMFTEL, CEI Moncloa, 28040 Madrid, Spain; (S.E.); (A.E.-R.); (M.G.-D.); (V.M.-N.); (V.S.-T.); (J.M.U.); (V.V.-O.); (L.M.F.)
- Instituto de Investigación del Hospital Clínico San Carlos (IdISSC), Ciudad Universitaria, 28040 Madrid, Spain
| | - José Manuel Udías
- Nuclear Physics Group, Universidad Complutense de Madrid, IPARCOS &EMFTEL, CEI Moncloa, 28040 Madrid, Spain; (S.E.); (A.E.-R.); (M.G.-D.); (V.M.-N.); (V.S.-T.); (J.M.U.); (V.V.-O.); (L.M.F.)
- Instituto de Investigación del Hospital Clínico San Carlos (IdISSC), Ciudad Universitaria, 28040 Madrid, Spain
| | - Víctor Valladolid-Onecha
- Nuclear Physics Group, Universidad Complutense de Madrid, IPARCOS &EMFTEL, CEI Moncloa, 28040 Madrid, Spain; (S.E.); (A.E.-R.); (M.G.-D.); (V.M.-N.); (V.S.-T.); (J.M.U.); (V.V.-O.); (L.M.F.)
- Instituto de Investigación del Hospital Clínico San Carlos (IdISSC), Ciudad Universitaria, 28040 Madrid, Spain
| | - Miguel Á. Martín-Rey
- Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas CIEMAT, Hematopoietic Innovative Therapies Unit, 28040 Madrid, Spain;
| | - Edilia I. Almeida-Cordon
- Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas CIEMAT, Animal Facility Unit, 28040 Madrid, Spain;
| | - Sílvia Viñals i Onsès
- Center for Microanalysis of Materials (CMAM), Universidad Autónoma de Madrid, 28049 Madrid, Spain;
| | - José Manuel Pérez
- Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas CIEMAT, Medical Applications of Ionizing Radiation Unit, 28040 Madrid, Spain; (R.S.); (M.O.); (V.M.L.-R.); (N.M.); (J.I.L.); (E.R.); (J.M.P.)
| | - Luis Mario Fraile
- Nuclear Physics Group, Universidad Complutense de Madrid, IPARCOS &EMFTEL, CEI Moncloa, 28040 Madrid, Spain; (S.E.); (A.E.-R.); (M.G.-D.); (V.M.-N.); (V.S.-T.); (J.M.U.); (V.V.-O.); (L.M.F.)
- Instituto de Investigación del Hospital Clínico San Carlos (IdISSC), Ciudad Universitaria, 28040 Madrid, Spain
| | - Fernando Herranz
- Instituto de Química Médica—Consejo Superior de Investigaciones Científicas IQM-CSIC, Nanomedicine and Molecular Imaging Group, 28006 Madrid, Spain; (M.M.-H.)
| | - Miguel Ángel Morcillo
- Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas CIEMAT, Medical Applications of Ionizing Radiation Unit, 28040 Madrid, Spain; (R.S.); (M.O.); (V.M.L.-R.); (N.M.); (J.I.L.); (E.R.); (J.M.P.)
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Krokos G, MacKewn J, Dunn J, Marsden P. A review of PET attenuation correction methods for PET-MR. EJNMMI Phys 2023; 10:52. [PMID: 37695384 PMCID: PMC10495310 DOI: 10.1186/s40658-023-00569-0] [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: 04/14/2023] [Accepted: 08/07/2023] [Indexed: 09/12/2023] Open
Abstract
Despite being thirteen years since the installation of the first PET-MR system, the scanners constitute a very small proportion of the total hybrid PET systems installed. This is in stark contrast to the rapid expansion of the PET-CT scanner, which quickly established its importance in patient diagnosis within a similar timeframe. One of the main hurdles is the development of an accurate, reproducible and easy-to-use method for attenuation correction. Quantitative discrepancies in PET images between the manufacturer-provided MR methods and the more established CT- or transmission-based attenuation correction methods have led the scientific community in a continuous effort to develop a robust and accurate alternative. These can be divided into four broad categories: (i) MR-based, (ii) emission-based, (iii) atlas-based and the (iv) machine learning-based attenuation correction, which is rapidly gaining momentum. The first is based on segmenting the MR images in various tissues and allocating a predefined attenuation coefficient for each tissue. Emission-based attenuation correction methods aim in utilising the PET emission data by simultaneously reconstructing the radioactivity distribution and the attenuation image. Atlas-based attenuation correction methods aim to predict a CT or transmission image given an MR image of a new patient, by using databases containing CT or transmission images from the general population. Finally, in machine learning methods, a model that could predict the required image given the acquired MR or non-attenuation-corrected PET image is developed by exploiting the underlying features of the images. Deep learning methods are the dominant approach in this category. Compared to the more traditional machine learning, which uses structured data for building a model, deep learning makes direct use of the acquired images to identify underlying features. This up-to-date review goes through the literature of attenuation correction approaches in PET-MR after categorising them. The various approaches in each category are described and discussed. After exploring each category separately, a general overview is given of the current status and potential future approaches along with a comparison of the four outlined categories.
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Affiliation(s)
- Georgios Krokos
- School of Biomedical Engineering and Imaging Sciences, The PET Centre at St Thomas' Hospital London, King's College London, 1st Floor Lambeth Wing, Westminster Bridge Road, London, SE1 7EH, UK.
| | - Jane MacKewn
- School of Biomedical Engineering and Imaging Sciences, The PET Centre at St Thomas' Hospital London, King's College London, 1st Floor Lambeth Wing, Westminster Bridge Road, London, SE1 7EH, UK
| | - Joel Dunn
- School of Biomedical Engineering and Imaging Sciences, The PET Centre at St Thomas' Hospital London, King's College London, 1st Floor Lambeth Wing, Westminster Bridge Road, London, SE1 7EH, UK
| | - Paul Marsden
- School of Biomedical Engineering and Imaging Sciences, The PET Centre at St Thomas' Hospital London, King's College London, 1st Floor Lambeth Wing, Westminster Bridge Road, London, SE1 7EH, UK
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Petoukhova A, Snijder R, Vissers T, Ceha H, Struikmans H. In vivodosimetry in cancer patients undergoing intraoperative radiation therapy. Phys Med Biol 2023; 68:18TR01. [PMID: 37607566 DOI: 10.1088/1361-6560/acf2e4] [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: 12/17/2022] [Accepted: 08/22/2023] [Indexed: 08/24/2023]
Abstract
In vivodosimetry (IVD) is an important tool in external beam radiotherapy (EBRT) to detect major errors by assessing differences between expected and delivered dose and to record the received dose by individual patients. Also, in intraoperative radiation therapy (IORT), IVD is highly relevant to register the delivered dose. This is especially relevant in low-risk breast cancer patients since a high dose of IORT is delivered in a single fraction. In contrast to EBRT, online treatment planning based on intraoperative imaging is only under development for IORT. Up to date, two commercial treatment planning systems proposed intraoperative ultrasound or in-room cone-beam CT for real-time IORT planning. This makes IVD even more important because of the possibility for real-time treatment adaptation. Here, we summarize recent developments and applications of IVD methods for IORT in clinical practice, highlighting important contributions and identifying specific challenges such as a treatment planning system for IORT. HDR brachytherapy as a delivery technique was not considered. We add IVD for ultrahigh dose rate (FLASH) radiotherapy that promises to improve the treatment efficacy, when compared to conventional radiotherapy by limiting the rate of toxicity while maintaining similar tumour control probabilities. To date, FLASH IORT is not yet in clinical use.
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Affiliation(s)
- Anna Petoukhova
- Haaglanden Medical Centre , Department of Medical Physics, Leidschendam, The Netherlands
| | - Roland Snijder
- Haaglanden Medical Centre , Department of Medical Physics, Leidschendam, The Netherlands
| | - Thomas Vissers
- Haaglanden Medical Centre , Medical Library, Leidschendam, The Netherlands
| | - Heleen Ceha
- Haaglanden Medical Centre , Department of Radiation Oncology, Leidschendam, The Netherlands
| | - Henk Struikmans
- Haaglanden Medical Centre , Department of Radiation Oncology, Leidschendam, The Netherlands
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Long X, Chen J, Liu W, Tian C. Deep Learning Ultrasound Computed Tomography Under Sparse Sampling. IEEE Trans Ultrason Ferroelectr Freq Control 2023; 70:1084-1100. [PMID: 37523276 DOI: 10.1109/tuffc.2023.3299954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/02/2023]
Abstract
Ultrasound computed tomography (USCT) is a fast-emerging imaging modality that is expected to help detect and characterize breast tumors by quantifying the distribution of the speed of sound (SOS) and acoustic attenuation in breast tissue. High-quality quantitative SOS reconstruction in USCT requires a large number of transducers, which incurs high system costs and slow computation. In contrast, sparsely distributed arrays are low-cost and fast but significantly degrade image quality. Thus, we propose a framework to achieve high-quality SOS reconstruction under sparse sampling based on a convolutional neural network (SRSS-Net) with faster computation. We first apply the bent-ray algorithm to sparsely sampled data and then apply the SRSS-Net to efficiently improve the image quality. Experimental results on synthetic and real datasets demonstrate that the proposed SRSS-Net provides reconstructions that are superior to those of state-of-the-art methods in terms of artifact suppression, structural preservation, quantitative restoration, and computational speed. As demonstrated in our experiments, the fine-tuning training strategy is suggested when applying SRSS-Net to real-world circumstances. The imaging and computational performance of SRSS-Net on the inhomogeneous breast phantom further demonstrates that SRSS-Net has great potential in real-time breast cancer detection.
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Vu T, Klippel P, Canning AJ, Ma C, Zhang H, Kasatkina LA, Tang Y, Xia J, Verkhusha VV, Vo-Dinh T, Jing Y, Yao J. On the importance of low-frequency signals in functional and molecular photoacoustic computed tomography. ArXiv 2023:arXiv:2308.00870v1. [PMID: 37576129 PMCID: PMC10418541] [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] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
In photoacoustic computed tomography (PACT) with short-pulsed laser excitation, wideband acoustic signals are generated in biological tissues with frequencies related to the effective shapes and sizes of the optically absorbing targets. Low-frequency photoacoustic signal components correspond to slowly varying spatial features and are often omitted during imaging due to the limited detection bandwidth of the ultrasound transducer, or during image reconstruction as undesired background that degrades image contrast. Here we demonstrate that low-frequency photoacoustic signals, in fact, contain functional and molecular information, and can be used to enhance structural visibility, improve quantitative accuracy, and reduce spare-sampling artifacts. We provide an in-depth theoretical analysis of low-frequency signals in PACT, and experimentally evaluate their impact on several representative PACT applications, such as mapping temperature in photothermal treatment, measuring blood oxygenation in a hypoxia challenge, and detecting photoswitchable molecular probes in deep organs. Our results strongly suggest that low-frequency signals are important for functional and molecular PACT.
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Affiliation(s)
- Tri Vu
- Photoacoustic Imaging Laboratory, Duke University, Durham, NC 27708 USA
| | - Paul Klippel
- Graduate Program in Acoustics, Penn State University, University Park, PA 16802
| | - Aidan J Canning
- Department of Biomedical Engineering, Department of Chemistry, and Fitzpatrick Institute of Photonics, Duke University, Durham, NC 27708
| | - Chenshuo Ma
- Photoacoustic Imaging Laboratory, Duke University, Durham, NC 27708 USA
| | - Huijuan Zhang
- Department of Biomedical Engineering, State University of New York, Buffalo, NY 14260
| | - Ludmila A Kasatkina
- Department of Genetics and Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, Bronx, NY 10461
| | - Yuqi Tang
- Photoacoustic Imaging Laboratory, Duke University, Durham, NC 27708 USA
| | - Jun Xia
- Department of Biomedical Engineering, State University of New York, Buffalo, NY 14260
| | - Vladislav V Verkhusha
- Department of Genetics and Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, Bronx, NY 10461
| | - Tuan Vo-Dinh
- Department of Biomedical Engineering, Department of Chemistry, and Fitzpatrick Institute of Photonics, Duke University, Durham, NC 27708
| | - Yun Jing
- Graduate Program in Acoustics, Penn State University, University Park, PA 16802
| | - Junjie Yao
- Photoacoustic Imaging Laboratory, Duke University, Durham, NC 27708 USA
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Ni R, Straumann N, Fazio S, Dean-Ben XL, Louloudis G, Keller C, Razansky D, Ametamey S, Mu L, Nombela-Arrieta C, Klohs J. Imaging increased metabolism in the spinal cord in mice after middle cerebral artery occlusion. Photoacoustics 2023; 32:100532. [PMID: 37645255 PMCID: PMC10461215 DOI: 10.1016/j.pacs.2023.100532] [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] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 07/13/2023] [Accepted: 07/13/2023] [Indexed: 08/31/2023]
Abstract
Emerging evidence indicates crosstalk between the brain and hematopoietic system following cerebral ischemia. Here, we investigated metabolism and oxygenation in the spleen and spinal cord in a transient middle cerebral artery occlusion (tMCAO) model. Sham-operated and tMCAO mice underwent [18F]fluorodeoxyglucose (FDG)-positron emission tomography (PET) to assess glucose metabolism. Naïve, sham-operated and tMCAO mice underwent multispectral optoacoustic tomography (MSOT) assisted by quantitative model-based reconstruction and unmixing algorithms for accurate mapping of oxygenation patterns in peripheral tissues at 24 h after reperfusion. We found increased [18F]FDG uptake and reduced MSOT oxygen saturation, indicating hypoxia in the thoracic spinal cord of tMCAO mice compared with sham-operated mice but not in the spleen. Reduced spleen size was observed in tMCAO mice compared with sham-operated mice ex vivo. tMCAO led to an increase in the numbers of mature T cells in femoral bone marrow tissues, concomitant with a stark reduction in these cell subsets in the spleen and peripheral blood. The combination of quantitative PET and MSOT thus enabled observation of hypoxia and increased metabolic activity in the spinal cord of tMCAO mice at 24 h after occlusion compared to sham-operated mice.
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Affiliation(s)
- Ruiqing Ni
- Institute for Regenerative Medicine, University of Zurich, Zurich, Switzerland
- Institute for Biomedical Engineering, Department of Information Technology and Electrical Engineering, University of Zurich & ETH Zurich, Zurich, Switzerland
- Zentrum für Neurowissenschaften Zurich, Zurich, Switzerland
| | - Nadja Straumann
- Institute for Regenerative Medicine, University of Zurich, Zurich, Switzerland
| | - Serana Fazio
- Department of Medical Oncology and Hematology, University and University Hospital Zurich, Zurich, Switzerland
| | - Xose Luis Dean-Ben
- Institute for Biomedical Engineering, Department of Information Technology and Electrical Engineering, University of Zurich & ETH Zurich, Zurich, Switzerland
| | - Georgios Louloudis
- Institute for Biomedical Engineering, Department of Information Technology and Electrical Engineering, University of Zurich & ETH Zurich, Zurich, Switzerland
| | - Claudia Keller
- Center for Radiopharmaceutical Sciences ETH, PSI and USZ, Institute of Pharmaceutical Sciences, Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich, Switzerland
| | - Daniel Razansky
- Institute for Biomedical Engineering, Department of Information Technology and Electrical Engineering, University of Zurich & ETH Zurich, Zurich, Switzerland
- Zentrum für Neurowissenschaften Zurich, Zurich, Switzerland
| | - Simon Ametamey
- Center for Radiopharmaceutical Sciences ETH, PSI and USZ, Institute of Pharmaceutical Sciences, Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich, Switzerland
| | - Linjing Mu
- Center for Radiopharmaceutical Sciences ETH, PSI and USZ, Institute of Pharmaceutical Sciences, Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich, Switzerland
| | - César Nombela-Arrieta
- Department of Medical Oncology and Hematology, University and University Hospital Zurich, Zurich, Switzerland
| | - Jan Klohs
- Institute for Biomedical Engineering, Department of Information Technology and Electrical Engineering, University of Zurich & ETH Zurich, Zurich, Switzerland
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Drainville RA, Chatillon S, Moore D, Snell J, Padilla F, Lafon C. A simulation study on the sensitivity of transcranial ray-tracing ultrasound modeling to skull properties. J Acoust Soc Am 2023; 154:1211-1225. [PMID: 37610718 DOI: 10.1121/10.0020761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Accepted: 08/08/2023] [Indexed: 08/24/2023]
Abstract
In transcranial focused ultrasound therapies, such as treating essential tremor via thermal ablation in the thalamus, acoustic energy is focused through the skull using a phased-array transducer. Ray tracing is a computationally efficient method that can correct skull-induced phase aberrations via per-element phase delay calculations using patient-specific computed tomography (CT) data. However, recent studies show that variations in CT-derived Hounsfield unit may account for only 50% of the speed of sound variability in human skull specimens, potentially limiting clinical transcranial ultrasound applications. Therefore, understanding the sensitivity of treatment planning methods to material parameter variations is essential. The present work uses a ray-tracing simulation model to explore how imprecision in model inputs, arising from clinically significant uncertainties in skull properties or considerations of acoustic phenomena, affects acoustic focusing quality through the skull. We propose and validate new methods to optimize ray-tracing skull simulations for clinical treatment planning, relevant for predicting intracranial target's thermal rise, using experimental data from ex-vivo human skulls.
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Affiliation(s)
| | | | - David Moore
- Focused Ultrasound Foundation, Charlottesville, Virginia 22903, USA
| | - John Snell
- Histosonics, Ann Arbor, Michigan 48103, USA
| | - Frederic Padilla
- Focused Ultrasound Foundation, Charlottesville, Virginia 22903, USA
| | - Cyril Lafon
- LabTAU, INSERM, Centre Léon Bérard, Université Lyon 1, Univ Lyon, F-69003, Lyon, France
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Zhang Y, Chen J, Zhang J, Zhu J, Liu C, Sun H, Wang L. Super-Low-Dose Functional and Molecular Photoacoustic Microscopy. Adv Sci (Weinh) 2023; 10:e2302486. [PMID: 37310419 PMCID: PMC10427362 DOI: 10.1002/advs.202302486] [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] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 05/21/2023] [Indexed: 06/14/2023]
Abstract
Photoacoustic microscopy can image many biological molecules and nano-agents in vivo via low-scattering ultrasonic sensing. Insufficient sensitivity is a long-standing obstacle for imaging low-absorbing chromophores with less photobleaching or toxicity, reduced perturbation to delicate organs, and more choices of low-power lasers. Here, the photoacoustic probe design is collaboratively optimized and a spectral-spatial filter is implemented. A multi-spectral super-low-dose photoacoustic microscopy (SLD-PAM) is presented that improves the sensitivity by ≈33 times. SLD-PAM can visualize microvessels and quantify oxygen saturation in vivo with ≈1% of the maximum permissible exposure, dramatically reducing potential phototoxicity or perturbation to normal tissue function, especially in imaging of delicate tissues, such as the eye and the brain. Capitalizing on the high sensitivity, direct imaging of deoxyhemoglobin concentration is achieved without spectral unmixing, avoiding wavelength-dependent errors and computational noises. With reduced laser power, SLD-PAM can reduce photobleaching by ≈85%. It is also demonstrated that SLD-PAM achieves similar molecular imaging quality using 80% fewer contrast agents. Therefore, SLD-PAM enables the use of a broader range of low-absorbing nano-agents, small molecules, and genetically encoded biomarkers, as well as more types of low-power light sources in wide spectra. It is believed that SLD-PAM offers a powerful tool for anatomical, functional, and molecular imaging.
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Affiliation(s)
- Yachao Zhang
- Department of Biomedical EngineeringCity University of Hong KongHong KongSAR999077China
| | - Jiangbo Chen
- Department of Biomedical EngineeringCity University of Hong KongHong KongSAR999077China
| | - Jie Zhang
- Department of Chemistry and COSADAF (Centre of Super‐Diamond and Advanced Films)City University of Hong KongHong KongSAR999077China
| | - Jingyi Zhu
- Department of Biomedical EngineeringCity University of Hong KongHong KongSAR999077China
| | - Chao Liu
- Department of Biomedical EngineeringCity University of Hong KongHong KongSAR999077China
| | - Hongyan Sun
- Department of Chemistry and COSADAF (Centre of Super‐Diamond and Advanced Films)City University of Hong KongHong KongSAR999077China
| | - Lidai Wang
- Department of Biomedical EngineeringCity University of Hong KongHong KongSAR999077China
- City University of Hong Kong Shenzhen Research InstituteShenzhenChina518057
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48
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Pratt EC, Lopez-Montes A, Volpe A, Crowley MJ, Carter LM, Mittal V, Pillarsetty N, Ponomarev V, Udías JM, Grimm J, Herraiz JL. Simultaneous quantitative imaging of two PET radiotracers via the detection of positron-electron annihilation and prompt gamma emissions. Nat Biomed Eng 2023; 7:1028-1039. [PMID: 37400715 PMCID: PMC10810307 DOI: 10.1038/s41551-023-01060-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Accepted: 05/23/2023] [Indexed: 07/05/2023]
Abstract
In conventional positron emission tomography (PET), only one radiotracer can be imaged at a time, because all PET isotopes produce the same two 511 keV annihilation photons. Here we describe an image reconstruction method for the simultaneous in vivo imaging of two PET tracers and thereby the independent quantification of two molecular signals. This method of multiplexed PET imaging leverages the 350-700 keV range to maximize the capture of 511 keV annihilation photons and prompt γ-ray emission in the same energy window, hence eliminating the need for energy discrimination during reconstruction or for signal separation beforehand. We used multiplexed PET to track, in mice with subcutaneous tumours, the biodistributions of intravenously injected [124I]I-trametinib and 2-deoxy-2-[18F]fluoro-D-glucose, [124I]I-trametinib and its nanoparticle carrier [89Zr]Zr-ferumoxytol, and the prostate-specific membrane antigen (PSMA) and infused PSMA-targeted chimaeric antigen receptor T cells after the systemic administration of [68Ga]Ga-PSMA-11 and [124I]I. Multiplexed PET provides more information depth, gives new uses to prompt γ-ray-emitting isotopes, reduces radiation burden by omitting the need for an additional computed-tomography scan and can be implemented on preclinical and clinical systems without any modifications in hardware or image acquisition software.
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Affiliation(s)
- Edwin C Pratt
- Department of Pharmacology, Weill Cornell Graduate School, New York, NY, USA
- Molecular Pharmacology, Memorial Sloan Kettering Cancer Center, New York, NY, USA
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Alejandro Lopez-Montes
- Nuclear Physics Group, EMFTEL and IPARCOS, Complutense University of Madrid, Madrid, Spain
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Alessia Volpe
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Michael J Crowley
- Department of Cell and Developmental Biology, Weill Cornell Graduate School, New York, NY, USA
| | - Lukas M Carter
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Vivek Mittal
- Department of Cell and Developmental Biology, Weill Cornell Graduate School, New York, NY, USA
- Department of Cardiothoracic Surgery, Weill Cornell Medicine, New York, USA
- Neuberger Berman Lung Cancer Center, Weill Cornell Medicine, New York, USA
- Sandra and Edward Meyer Cancer Center, Weill Cornell Medicine, New York, USA
| | | | - Vladimir Ponomarev
- Molecular Pharmacology, Memorial Sloan Kettering Cancer Center, New York, NY, USA
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Jose M Udías
- Nuclear Physics Group, EMFTEL and IPARCOS, Complutense University of Madrid, Madrid, Spain
- Instituto de Investigación Sanitaria Hospital Clínico San Carlos, Madrid, Spain
| | - Jan Grimm
- Department of Pharmacology, Weill Cornell Graduate School, New York, NY, USA.
- Molecular Pharmacology, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
| | - Joaquin L Herraiz
- Nuclear Physics Group, EMFTEL and IPARCOS, Complutense University of Madrid, Madrid, Spain.
- Instituto de Investigación Sanitaria Hospital Clínico San Carlos, Madrid, Spain.
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49
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Kraft M, Ryger S, Berman BP, Downs ME, Jordanova KV, Poorman ME, Oberdick SD, Ogier SE, Russek SE, Dagher J, Keenan KE. Towards a barrier-free anthropomorphic brain phantom for quantitative magnetic resonance imaging: Design, first construction attempt, and challenges. PLoS One 2023; 18:e0285432. [PMID: 37437022 DOI: 10.1371/journal.pone.0285432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Accepted: 04/21/2023] [Indexed: 07/14/2023] Open
Abstract
Existing magnetic resonance imaging (MRI) reference objects, or phantoms, are typically constructed from simple liquid or gel solutions in containers with specific geometric configurations to enable multi-year stability. However, there is a need for phantoms that better mimic the human anatomy without barriers between the tissues. Barriers result in regions without MRI signal between the different tissue mimics, which is an artificial image artifact. We created an anatomically representative 3D structure of the brain that mimicked the T1 and T2 relaxation properties of white and gray matter at 3 T. While the goal was to avoid barriers between tissues, the 3D printed barrier between white and gray matter and other flaws in the construction were visible at 3 T. Stability measurements were made using a portable MRI system operating at 64 mT, and T2 relaxation time was stable from 0 to 22 weeks. The phantom T1 relaxation properties did change from 0 to 10 weeks; however, they did not substantially change between 10 weeks and 22 weeks. The anthropomorphic phantom used a dissolvable mold construction method to better mimic anatomy, which worked in small test objects. The construction process, though, had many challenges. We share this work with the hope that the community can build on our experience.
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Affiliation(s)
- Mikail Kraft
- National Institute of Standards and Technology, Physical Measurement Laboratory, Boulder, Colorado, United States of America
| | - Slavka Ryger
- National Institute of Standards and Technology, Physical Measurement Laboratory, Boulder, Colorado, United States of America
| | - Ben P Berman
- The MITRE Corporation, McLean, Virginia, United States of America
| | - Matthew E Downs
- The MITRE Corporation, McLean, Virginia, United States of America
| | - Kalina V Jordanova
- National Institute of Standards and Technology, Physical Measurement Laboratory, Boulder, Colorado, United States of America
| | - Megan E Poorman
- Hyperfine, Inc, Guilford, Connecticut, United States of America
| | - Samuel D Oberdick
- National Institute of Standards and Technology, Physical Measurement Laboratory, Boulder, Colorado, United States of America
- Department of Physics, University of Colorado, Boulder, Colorado, United States of America
| | - Stephen E Ogier
- National Institute of Standards and Technology, Physical Measurement Laboratory, Boulder, Colorado, United States of America
- Department of Physics, University of Colorado, Boulder, Colorado, United States of America
| | - Stephen E Russek
- National Institute of Standards and Technology, Physical Measurement Laboratory, Boulder, Colorado, United States of America
| | - Joseph Dagher
- The MITRE Corporation, McLean, Virginia, United States of America
| | - Kathryn E Keenan
- National Institute of Standards and Technology, Physical Measurement Laboratory, Boulder, Colorado, United States of America
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50
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Titov SA, Burlakov AB, Zinin PV, Bogachenkov AN. Measurement of ultrasound velocity in yolk and blastula of fish embryo in vivo. Ultrasonics 2023; 132:106963. [PMID: 36863133 DOI: 10.1016/j.ultras.2023.106963] [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] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 11/24/2022] [Accepted: 02/13/2023] [Indexed: 05/29/2023]
Abstract
An acoustic microscopy method for measuring the velocity of ultrasound in the yolk and blastula of bony fish embryos at early stages of development was proposed. The yolk and blastula were approximated as a sphere and a spherical dome, respectively, consisting of a homogeneous liquid. A theoretical model of ultrasonic wave propagation through a spherical liquid drop located on a solid substrate was developed in the ray approximation. The dependence of the wave propagation time on the speed of sound in the drop, its diameter, and the position of the focus of the ultrasonic transducer has been determined. It was shown that the velocity in the drop can be found by solving the inverse problem by minimizing the discrepancy between the experimental and model spatial distributions of the propagation time, assuming that the velocity in the immersion liquid and the radius of the drop are known. The velocities in the yolk and blastula of the loach (Misgurnus fossilis) embryo at the stage of development of the middle blastula were measured in vivo using a pulsed scanning acoustic microscope operating at a central frequency of 50 MHz. The yolk and blastula radii were determined from ultrasound images of the embryo. Acoustic microscopy measurements conducted with four embryos provide velocities of the acoustic longitudinal wave in the yolk and blastula. They were measured to be 1581 ± 5 m/s and 1525 ± 4 m/s when the temperature of the liquid in the water tank was kept at 22 ± 2 °C.
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Affiliation(s)
- S A Titov
- Scientific and Technological Center for Unique Instrumentation of the Russian Academy of Sciences(STC UP RAS), 15 Butlerova str, Moscow 117342, Russia.
| | - A B Burlakov
- Lomonosov Moscow state University, 1 Leninskie Gory, Moscow 119991, Russia
| | - P V Zinin
- Scientific and Technological Center for Unique Instrumentation of the Russian Academy of Sciences(STC UP RAS), 15 Butlerova str, Moscow 117342, Russia
| | - A N Bogachenkov
- Institute of Biochemical Physics of the Russian Academy of Sciences, 4 Kosygina str, Moscow 119334, Russia
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