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Zhang X, Li H, Wang H, Liu X, Deng W, Zhong J, Fan L, Ling Q, Hu D, Qi H, Chen H. Iodine concentration, HU accuracy, and metal artifacts evaluation on second-generation dual-layer spectral detector CT images with metal implants: a phantom study. Acta Radiol 2024:2841851241269853. [PMID: 39140845 DOI: 10.1177/02841851241269853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/15/2024]
Abstract
BACKGROUND Metal implants may affect the image quality, iodine concentration (IC), and CT Hounsfield unit (HU) quantification accuracy. PURPOSE To investigate the quantitative accuracy of IC and HU from dual-layer spectral detector (DLCT) in the presence of metal artifacts. MATERIAL AND METHODS An experimental cylindrical phantom containing eight iodine inserts and two metal inserts was designed. The phantom underwent scanning at three radiation dose levels and two tube voltage settings. A set of conventional images (CIs), virtual monoenergetic images (VMIs), and iodine concentration maps (ICMs) were generated and measured for all the eight iodine inserts. Quantitative indicators of mean absolute percentage error (MAPE), artifact index (AI), contrast-to-noise ratio (CNR), signal-to-noise ratio (SNR), and standard deviation (SD) on CIs and VMIs were calculated for IC and HU. Subjective score evaluation was also conducted. RESULTS The MAPEiodine values of all regions of interest across different scanning configurations were all <5%. Almost all APEiodine values were <5%, indicating that metal artifacts had little impact on IC measurements. When the tube voltage was fixed, the SD value of attenuation decreased with the increase of the tube current; this is also true when the tube current was fixed. The middle energy reconstructions seemed to give a good balance between reducing artifacts and improving contrast. CONCLUSION VMIs from DLCT can reduce metal artifacts, the accuracy of IC quantification is not sensitive to imaging parameters. In summary, metal implants exhibit minimal impact on image quality and IC quantification accuracy in reconstructed images from DLCT.
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Affiliation(s)
- Xinming Zhang
- Department of Clinical Engineering, Nanfang Hospital, Southern Medical University, Guangzhou, PR China
- School of Biomedical Engineering, Southern Medical University, Guangzhou, PR China
| | - Hanwei Li
- Department of Clinical Engineering, Nanfang Hospital, Southern Medical University, Guangzhou, PR China
| | - Haowen Wang
- Department of Clinical Engineering, Nanfang Hospital, Southern Medical University, Guangzhou, PR China
| | - Xiaomin Liu
- Clinical and Technical Support, Philips Healthcare, Shanghai, PR China
| | - Weiwei Deng
- Clinical and Technical Support, Philips Healthcare, Shanghai, PR China
| | - Jianqiu Zhong
- Clinical and Technical Support, Philips Healthcare, Shanghai, PR China
| | - Litian Fan
- Department of Clinical Engineering, Nanfang Hospital, Southern Medical University, Guangzhou, PR China
| | - Qingqing Ling
- Department of Clinical Engineering, Nanfang Hospital, Southern Medical University, Guangzhou, PR China
| | - Debin Hu
- Department of Clinical Engineering, Nanfang Hospital, Southern Medical University, Guangzhou, PR China
| | - Hongliang Qi
- Department of Clinical Engineering, Nanfang Hospital, Southern Medical University, Guangzhou, PR China
| | - Hongwen Chen
- Department of Clinical Engineering, Nanfang Hospital, Southern Medical University, Guangzhou, PR China
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Shin DJ, Choi YH, Lee SB, Cho YJ, Lee S, Cheon JE. Low-iodine-dose computed tomography coupled with an artificial intelligence-based contrast-boosting technique in children: a retrospective study on comparison with conventional-iodine-dose computed tomography. Pediatr Radiol 2024; 54:1315-1324. [PMID: 38839610 PMCID: PMC11254996 DOI: 10.1007/s00247-024-05953-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Revised: 05/12/2024] [Accepted: 05/13/2024] [Indexed: 06/07/2024]
Abstract
BACKGROUND Low-iodine-dose computed tomography (CT) protocols have emerged to mitigate the risks associated with contrast injection, often resulting in decreased image quality. OBJECTIVE To evaluate the image quality of low-iodine-dose CT combined with an artificial intelligence (AI)-based contrast-boosting technique in abdominal CT, compared to a standard-iodine-dose protocol in children. MATERIALS AND METHODS This single-center retrospective study included 35 pediatric patients (mean age 9.2 years, range 1-17 years) who underwent sequential abdominal CT scans-one with a standard-iodine-dose protocol (standard-dose group, Iobitridol 350 mgI/mL) and another with a low-iodine-dose protocol (low-dose group, Iohexol 240 mgI/mL)-within a 4-month interval from January 2022 to July 2022. The low-iodine CT protocol was reconstructed using an AI-based contrast-boosting technique (contrast-boosted group). Quantitative and qualitative parameters were measured in the three groups. For qualitative parameters, interobserver agreement was assessed using the intraclass correlation coefficient, and mean values were employed for subsequent analyses. For quantitative analysis of the three groups, repeated measures one-way analysis of variance with post hoc pairwise analysis was used. For qualitative analysis, the Friedman test followed by post hoc pairwise analysis was used. Paired t-tests were employed to compare radiation dose and iodine uptake between the standard- and low-dose groups. RESULTS The standard-dose group exhibited higher attenuation, contrast-to-noise ratio (CNR), and signal-to-noise ratio (SNR) of organs and vessels compared to the low-dose group (all P-values < 0.05 except for liver SNR, P = 0.12). However, noise levels did not differ between the standard- and low-dose groups (P = 0.86). The contrast-boosted group had increased attenuation, CNR, and SNR of organs and vessels, and reduced noise compared with the low-dose group (all P < 0.05). The contrast-boosted group showed no differences in attenuation, CNR, and SNR of organs and vessels (all P > 0.05), and lower noise (P = 0.002), than the standard-dose group. In qualitative analysis, the contrast-boosted group did not differ regarding vessel enhancement and lesion conspicuity (P > 0.05) but had lower noise (P < 0.05) and higher organ enhancement and artifacts (all P < 0.05) than the standard-dose group. While iodine uptake was significantly reduced in low-iodine-dose CT (P < 0.001), there was no difference in radiation dose between standard- and low-iodine-dose CT (all P > 0.05). CONCLUSION Low-iodine-dose abdominal CT, combined with an AI-based contrast-boosting technique exhibited comparable organ and vessel enhancement, as well as lesion conspicuity compared to standard-iodine-dose CT in children. Moreover, image noise decreased in the contrast-boosted group, albeit with an increase in artifacts.
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Affiliation(s)
- Dong-Joo Shin
- Department of Radiology, Seoul National University Hospital, 101 Daehak-Ro, Jongno-Gu, Seoul, 03080, Republic of Korea
| | - Young Hun Choi
- Department of Radiology, Seoul National University Hospital, 101 Daehak-Ro, Jongno-Gu, Seoul, 03080, Republic of Korea.
- Department of Radiology, Seoul National University College of Medicine, Jongno-Gu, Seoul, Republic of Korea.
| | - Seul Bi Lee
- Department of Radiology, Seoul National University Hospital, 101 Daehak-Ro, Jongno-Gu, Seoul, 03080, Republic of Korea
- Department of Radiology, Seoul National University College of Medicine, Jongno-Gu, Seoul, Republic of Korea
| | - Yeon Jin Cho
- Department of Radiology, Seoul National University Hospital, 101 Daehak-Ro, Jongno-Gu, Seoul, 03080, Republic of Korea
- Department of Radiology, Seoul National University College of Medicine, Jongno-Gu, Seoul, Republic of Korea
| | - Seunghyun Lee
- Department of Radiology, Seoul National University Hospital, 101 Daehak-Ro, Jongno-Gu, Seoul, 03080, Republic of Korea
- Department of Radiology, Seoul National University College of Medicine, Jongno-Gu, Seoul, Republic of Korea
| | - Jung-Eun Cheon
- Department of Radiology, Seoul National University Hospital, 101 Daehak-Ro, Jongno-Gu, Seoul, 03080, Republic of Korea
- Department of Radiology, Seoul National University College of Medicine, Jongno-Gu, Seoul, Republic of Korea
- Institute of Radiation Medicine, Seoul National University Medical Research Center, Jongno-Gu, Seoul, Republic of Korea
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Neumann J, Nowak T, Schmidt B, von Zanthier J. An Image-Based Prior Knowledge-Free Approach for a Multi-Material Decomposition in Photon-Counting Computed Tomography. Diagnostics (Basel) 2024; 14:1262. [PMID: 38928677 PMCID: PMC11203122 DOI: 10.3390/diagnostics14121262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2024] [Revised: 06/07/2024] [Accepted: 06/13/2024] [Indexed: 06/28/2024] Open
Abstract
Photon-counting CT systems generally allow for acquiring multiple spectral datasets and thus for decomposing CT images into multiple materials. We introduce a prior knowledge-free deterministic material decomposition approach for quantifying three material concentrations on a commercial photon-counting CT system based on a single CT scan. We acquired two phantom measurement series: one to calibrate and one to test the algorithm. For evaluation, we used an anthropomorphic abdominal phantom with inserts of either aqueous iodine solution, aqueous tungsten solution, or water. Material CT numbers were predicted based on a polynomial in the following parameters: Water-equivalent object diameter, object center-to-isocenter distance, voxel-to-isocenter distance, voxel-to-object center distance, and X-ray tube current. The material decomposition was performed as a generalized least-squares estimation. The algorithm provided material maps of iodine, tungsten, and water with average estimation errors of 4% in the contrast agent maps and 1% in the water map with respect to the material concentrations in the inserts. The contrast-to-noise ratio in the iodine and tungsten map was 36% and 16% compared to the noise-minimal threshold image. We were able to decompose four spectral images into iodine, tungsten, and water.
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Affiliation(s)
- Jonas Neumann
- Quantum Optics and Quantum Information Group (QOQI), Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstr. 1, 91058 Erlangen, Germany
- Siemens Healthineers AG, Siemensstr. 3, 91301 Forchheim, Germany
| | - Tristan Nowak
- Siemens Healthineers AG, Siemensstr. 3, 91301 Forchheim, Germany
| | - Bernhard Schmidt
- Siemens Healthineers AG, Siemensstr. 3, 91301 Forchheim, Germany
| | - Joachim von Zanthier
- Quantum Optics and Quantum Information Group (QOQI), Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstr. 1, 91058 Erlangen, Germany
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Landsmann A, Sartoretti T, Mergen V, Jungblut L, Eberhard M, Kobe A, Alkadhi H, Euler A. Multi-Energy Low-Kiloelectron Volt versus Single-Energy Low-Kilovolt Images for Endoleak Detection at CT Angiography of the Aorta. Radiol Cardiothorac Imaging 2024; 6:e230217. [PMID: 38451189 PMCID: PMC11056760 DOI: 10.1148/ryct.230217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 01/14/2024] [Accepted: 01/23/2024] [Indexed: 03/08/2024]
Abstract
Purpose To compare image quality, diagnostic performance, and conspicuity between single-energy and multi-energy images for endoleak detection at CT angiography (CTA) after endovascular aortic repair (EVAR). Materials and Methods In this single-center prospective randomized controlled trial, individuals undergoing CTA after EVAR between August 2020 and May 2022 were allocated to imaging using either low-kilovolt single-energy images (SEI; 80 kV, group A) or low-kiloelectron volt virtual monoenergetic images (VMI) at 40 and 50 keV from multi-energy CT (80/Sn150 kV, group B). Scan protocols were dose matched (volume CT dose index: mean, 4.5 mGy ± 1.8 [SD] vs 4.7 mGy ± 1.3, P = .41). Contrast-to-noise ratio (CNR) was measured. Two expert radiologists established the reference standard for the presence of endoleaks. Detection and conspicuity of endoleaks and subjective image quality were assessed by two different blinded radiologists. Interreader agreement was calculated. Nonparametric statistical tests were used. Results A total of 125 participants (mean age, 76 years ± 8; 103 men) were allocated to groups A (n = 64) and B (n = 61). CNR was significantly lower for 40-keV VMI (mean, 19.1; P = .048) and 50-keV VMI (mean, 16.8; P < .001) as compared with SEI (mean, 22.2). In total, 45 endoleaks were present (A: 23 vs B: 22). Sensitivity for endoleak detection was higher for SEI (82.6%, 19 of 23; P = .88) and 50-keV VMI (81.8%, 18 of 22; P = .90) as compared with 40-keV VMI (77.3%, 17 of 22). Specificity was comparable among groups (SEI: 92.7%, 38 of 41; both VMI energies: 92.3%, 35 of 38; P = .99), with an interreader agreement of 1. Conspicuity of endoleaks was comparable between SEI (median, 2.99) and VMI (both energies: median, 2.87; P = .04). Overall subjective image quality was rated significantly higher for SEI (median, 4 [IQR, 4-4) as compared with 40 and 50 keV (both energies: median, 4 [IQR, 3-4]; P < .001). Conclusion SEI demonstrated higher image quality and comparable diagnostic accuracy as compared with 50-keV VMI for endoleak detection at CTA after EVAR. Keywords: Aneurysms, CT, CT Angiography, Vascular, Aorta, Technology Assessment, Multidetector CT, Abdominal Aortic Aneurysms, Endoleaks, Perigraft Leak Supplemental material is available for this article. © RSNA, 2024.
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Affiliation(s)
- Anna Landsmann
- From the Department of Diagnostic and Interventional Radiology,
University Hospital Zurich, University of Zurich, Rämistrasse 100, 8091
Zurich, Switzerland (A.L., T.S., V.M., L.J., M.E., A.K., H.A., A.E.); Department
of Radiology, Spital Interlaken, Spitäler fmi AG, Unterseen, Switzerland
(M.E.); and Department of Radiology, Kantonsspital Baden, Baden, Switzerland
(A.E.)
| | - Thomas Sartoretti
- From the Department of Diagnostic and Interventional Radiology,
University Hospital Zurich, University of Zurich, Rämistrasse 100, 8091
Zurich, Switzerland (A.L., T.S., V.M., L.J., M.E., A.K., H.A., A.E.); Department
of Radiology, Spital Interlaken, Spitäler fmi AG, Unterseen, Switzerland
(M.E.); and Department of Radiology, Kantonsspital Baden, Baden, Switzerland
(A.E.)
| | - Victor Mergen
- From the Department of Diagnostic and Interventional Radiology,
University Hospital Zurich, University of Zurich, Rämistrasse 100, 8091
Zurich, Switzerland (A.L., T.S., V.M., L.J., M.E., A.K., H.A., A.E.); Department
of Radiology, Spital Interlaken, Spitäler fmi AG, Unterseen, Switzerland
(M.E.); and Department of Radiology, Kantonsspital Baden, Baden, Switzerland
(A.E.)
| | - Lisa Jungblut
- From the Department of Diagnostic and Interventional Radiology,
University Hospital Zurich, University of Zurich, Rämistrasse 100, 8091
Zurich, Switzerland (A.L., T.S., V.M., L.J., M.E., A.K., H.A., A.E.); Department
of Radiology, Spital Interlaken, Spitäler fmi AG, Unterseen, Switzerland
(M.E.); and Department of Radiology, Kantonsspital Baden, Baden, Switzerland
(A.E.)
| | - Matthias Eberhard
- From the Department of Diagnostic and Interventional Radiology,
University Hospital Zurich, University of Zurich, Rämistrasse 100, 8091
Zurich, Switzerland (A.L., T.S., V.M., L.J., M.E., A.K., H.A., A.E.); Department
of Radiology, Spital Interlaken, Spitäler fmi AG, Unterseen, Switzerland
(M.E.); and Department of Radiology, Kantonsspital Baden, Baden, Switzerland
(A.E.)
| | - Adrian Kobe
- From the Department of Diagnostic and Interventional Radiology,
University Hospital Zurich, University of Zurich, Rämistrasse 100, 8091
Zurich, Switzerland (A.L., T.S., V.M., L.J., M.E., A.K., H.A., A.E.); Department
of Radiology, Spital Interlaken, Spitäler fmi AG, Unterseen, Switzerland
(M.E.); and Department of Radiology, Kantonsspital Baden, Baden, Switzerland
(A.E.)
| | - Hatem Alkadhi
- From the Department of Diagnostic and Interventional Radiology,
University Hospital Zurich, University of Zurich, Rämistrasse 100, 8091
Zurich, Switzerland (A.L., T.S., V.M., L.J., M.E., A.K., H.A., A.E.); Department
of Radiology, Spital Interlaken, Spitäler fmi AG, Unterseen, Switzerland
(M.E.); and Department of Radiology, Kantonsspital Baden, Baden, Switzerland
(A.E.)
| | - André Euler
- From the Department of Diagnostic and Interventional Radiology,
University Hospital Zurich, University of Zurich, Rämistrasse 100, 8091
Zurich, Switzerland (A.L., T.S., V.M., L.J., M.E., A.K., H.A., A.E.); Department
of Radiology, Spital Interlaken, Spitäler fmi AG, Unterseen, Switzerland
(M.E.); and Department of Radiology, Kantonsspital Baden, Baden, Switzerland
(A.E.)
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Monnin P, Rotzinger D, Viry A, Vitzthum V, Racine D. Assessment of temporal resolution and detectability of moving objects in CT: A task-based image quality study. Phys Med 2024; 120:103337. [PMID: 38552274 DOI: 10.1016/j.ejmp.2024.103337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 03/12/2024] [Accepted: 03/25/2024] [Indexed: 04/19/2024] Open
Abstract
The metrics used for assessing image quality in computed tomography (CT) do not integrate the influence of temporal resolution. A shortcoming in the assessment of image quality for imaging protocols where motion blur can therefore occur. We developed a method to calculate the temporal resolution of standard CT protocols and introduced a specific spatiotemporal formulation of the non-prewhitening with eye filter (NPWE) model observer to assess the detectability of moving objects as a function of their speed. We scanned a cubic water phantom with a plexiglass cylindrical insert (120 HU) using a large panel of acquisition parameters (rotation times, pitch factors and collimation widths) on two systems (GE Revolution Apex and Siemens SOMATOM Force) to determine the in-plane task-based transfer functions (TTF) and noise power spectra (NPS). The phantom set in a uniform rectilinear motion in the transverse plane allowed the temporal modulation transfer function (MTF) calculation. The temporal MTF appropriately compared the temporal resolution of the various acquisition protocols. The longitudinal TTF was measured using a thin tungsten wire. The detectability index showed the advantage of applying high rotation speed, wide collimations and high pitch for object detection in the presence of motion. No counterpart to the increase in these three parameters was found in the in-plane and longitudinal image quality.
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Affiliation(s)
- P Monnin
- Institute of Radiation Physics (IRA), Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Rue du Grand-Pré 1, 1007 Lausanne, Switzerland.
| | - D Rotzinger
- Department of Diagnostic and Interventional Radiology, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Rue du Bugnon 46, 1011 Lausanne, Switzerland
| | - A Viry
- Institute of Radiation Physics (IRA), Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Rue du Grand-Pré 1, 1007 Lausanne, Switzerland
| | - V Vitzthum
- Institute of Radiation Physics (IRA), Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Rue du Grand-Pré 1, 1007 Lausanne, Switzerland
| | - D Racine
- Institute of Radiation Physics (IRA), Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Rue du Grand-Pré 1, 1007 Lausanne, Switzerland
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Song Q, Wang X, Zhu J, Shi H. Diagnostic value of dual-source, dual-energy computed tomography combined with the neutrophil-lymphocyte ratio for discriminating gastric signet ring cell from mixed signet ring cell and non-signet ring cell carcinomas. Abdom Radiol (NY) 2024:10.1007/s00261-024-04286-9. [PMID: 38526596 DOI: 10.1007/s00261-024-04286-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2024] [Revised: 03/08/2024] [Accepted: 03/08/2024] [Indexed: 03/26/2024]
Abstract
PURPOSE To explore the diagnostic value of dual-source computed tomography (DSCT) and neutrophil to lymphocyte ratio (NLR) for differentiating gastric signet ring cell carcinoma (SRC) from mixed SRC (mSRC) and non-SRC (nSRC). METHODS This retrospective study included patients with gastric adenocarcinoma who underwent DSCT between August 2019 and June 2021 at our Hospital. The iodine concentration in the venous phase (ICvp), standardized iodine concentration (NICVP), and the slope of the energy spectrum curve (kVP) were extracted from DSCT data. NLR was determined from laboratory results. DSCT (including ICVP, NICVP, and kVP) and combination (including DSCT model and NLR) models were established based on the multinomial logistic regression analysis. The receiver operator characteristic (ROC) curve and area under the curve (AUC) were used to evaluate the diagnostic value. RESULTS A total of 155 patients (SRC [n = 45, aged 61.22 ± 11.4 years], mSRC [n = 60, aged 61.09 ± 12.7 years], and nSRC [n = 50, aged 67.66 ± 8.76 years]) were included. There were significant differences in NLR, ICVP, NICVP, and kVP among the SRC, mSRC, and nSRC groups (all P < 0.001). The AUC of the combination model for SRC vs. mSRC + nSRC was 0.964 (95% CI: 0.923-1.000), with a sensitivity of 98.3% and a specificity of 86.7%, higher than with DSCT (AUC: 0.959, 95% CI: 0.919-0.998, sensitivity: 90.0%, specificity: 89.9%) or NLR (AUC: 0.670, 95% CI: 0.577-0.768, sensitivity: 62.2%, specificity: 61.8%). CONCLUSION DSCT combined with NLR showed high diagnostic efficacy in differentiating SRC from mSRC and nSRC.
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Affiliation(s)
- Qinxia Song
- Department of radiology, Anqing Municipal Hospital, Anqing, 246000, Anhui province, China
| | - Xiangfa Wang
- Department of radiology, Anqing Municipal Hospital, Anqing, 246000, Anhui province, China.
| | - Juan Zhu
- Department of radiology, Anqing Municipal Hospital, Anqing, 246000, Anhui province, China
| | - Hengfeng Shi
- Department of radiology, Anqing Municipal Hospital, Anqing, 246000, Anhui province, China
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Tian X, Chen Y, Pan S, Lan H, Cheng L. Enhanced in-stent luminal visualization and restenosis diagnosis in coronary computed tomography angiography via coronary stent decomposition algorithm from dual-energy image. Comput Biol Med 2024; 171:108128. [PMID: 38342047 DOI: 10.1016/j.compbiomed.2024.108128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 01/17/2024] [Accepted: 02/06/2024] [Indexed: 02/13/2024]
Abstract
Stent implantation is a principal therapeutic approach for coronary artery diseases. Nonetheless, the presence of stents significantly interferes with in-stent luminal (ISL) visualization and complicates the diagnosis of in-stent restenosis (ISR), thereby increasing the risk of misdiagnoses and underdiagnoses in coronary computed tomography angiography (CCTA). Dual-energy (DE) CT could calculate the volume fraction for voxels from low- and high-energy images (LHEI) and provide information on specific three basic materials. In this study, the innovative coronary stent decomposition algorithm (CSDA) was developed from the DECT three materials decomposition (TMD), through spectral simulation to determine the scan and attenuation coefficient for the stent, and preliminary execution for an in vitro sophisticated polyether ether ketone (PEEK) 3D-printed right coronary artery (RCA) replica. Furthermore, the whole-coronary-artery replica with multi-stent implantation, the RCA replica with mimetic plaque embedded, and two patients with stent further validated the effectiveness of CSDA. Post-CSDA images manifested no weakened attenuation values, no elevated noise values, and maintained anatomical integrity in the coronary lumen. The stents were effectively removed, allowing for the ISL and ISR to be clearly visualized with a discrepancy in diameters within 10%. We believe that CSDA presents a promising solution for enhancing CCTA diagnostic accuracy post-stent implantation.
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Affiliation(s)
- Xin Tian
- Department of Medical Imaging, Jincheng People's Hospital, Jincheng, 048000, China.
| | - Yunbing Chen
- Department of Medical Imaging, Jincheng People's Hospital, Jincheng, 048000, China
| | - Sancong Pan
- Department of Cardiovascular Medicine, Jincheng People's Hospital, Jincheng, 048000, China
| | - Honglin Lan
- Department of Medical Imaging, Jincheng People's Hospital, Jincheng, 048000, China
| | - Lei Cheng
- The First Affiliated Hospital of Anhui Medical University, Hefei, 230022, China.
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Ma C, Su T, Zhu J, Zhang X, Zheng H, Liang D, Wang N, Zhang Y, Ge Y. Performance evaluation of quantitative material decomposition in slow kVp switching dual-energy CT. JOURNAL OF X-RAY SCIENCE AND TECHNOLOGY 2024; 32:69-85. [PMID: 38189729 DOI: 10.3233/xst-230201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
BACKGROUND Slow kVp switching technique is an important approach to realize dual-energy CT (DECT) imaging, but its performance has not been thoroughly investigated yet. OBJECTIVE This study aims at comparing and evaluating the DECT imaging performance of different slow kVp switching protocols, and thus helps determining the optimal system settings. METHODS To investigate the impact of energy separation, two different beam filtration schemes are compared: the stationary beam filtration and dynamic beam filtration. Moreover, uniform tube voltage modulation and weighted tube voltage modulation are compared along with various modulation frequencies. A model-based direct decomposition algorithm is employed to generate the water and iodine material bases. Both numerical and physical experiments are conducted to verify the slow kVp switching DECT imaging performance. RESULTS Numerical and experimental results demonstrate that the material decomposition is less sensitive to beam filtration, voltage modulation type and modulation frequency. As a result, robust material-specific quantitative decomposition can be achieved in slow kVp switching DECT imaging. CONCLUSIONS Quantitative DECT imaging can be implemented with slow kVp switching under a variety of system settings.
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Affiliation(s)
- Chenchen Ma
- School of Mechanical Engineering and Automation, Northeastern University, Shenyang, China
| | - Ting Su
- Research Center for Medical Artificial Intelligence, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China
| | - Jiongtao Zhu
- Research Center for Medical Artificial Intelligence, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China
| | - Xin Zhang
- Research Center for Medical Artificial Intelligence, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China
| | - Hairong Zheng
- Paul C Lauterbur Research Center for Biomedical Imaging, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China
- National Innovation Center for Advanced Medical Devices, Shenzhen, Guangdong, China
- Key Laboratory of Biomedical Imaging Science and System, Chinese Academy of Sciences, Shenzhen, Guangdong, China
| | - Dong Liang
- Research Center for Medical Artificial Intelligence, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China
- Paul C Lauterbur Research Center for Biomedical Imaging, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China
- Key Laboratory of Biomedical Imaging Science and System, Chinese Academy of Sciences, Shenzhen, Guangdong, China
| | - Na Wang
- School of Mechanical Engineering and Automation, Northeastern University, Shenyang, China
| | - Yunxin Zhang
- Department of Vascular Surgery, Beijing Jishuitan Hospital, Beijing, China
| | - Yongshuai Ge
- Research Center for Medical Artificial Intelligence, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China
- Paul C Lauterbur Research Center for Biomedical Imaging, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China
- National Innovation Center for Advanced Medical Devices, Shenzhen, Guangdong, China
- Key Laboratory of Biomedical Imaging Science and System, Chinese Academy of Sciences, Shenzhen, Guangdong, China
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Mergen V, Sartoretti T, Cundari G, Serifovic M, Higashigaito K, Allmendinger T, Schmidt B, Flohr T, Manka R, Eberhard M, Alkadhi H. The Importance of Temporal Resolution for Ultra-High-Resolution Coronary Angiography: Evidence From Photon-Counting Detector CT. Invest Radiol 2023; 58:767-774. [PMID: 37222522 DOI: 10.1097/rli.0000000000000987] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
PURPOSE The aim of this study was to assess the effect of temporal resolution on subjective and objective image quality of coronary computed tomography angiography (CCTA) in the ultra-high-resolution (UHR) mode with dual-source photon-counting detector (PCD) CT. MATERIALS AND METHODS This retrospective, institutional review board-approved study evaluated 30 patients (9 women; mean age, 80 ± 10 years) undergoing UHR CCTA with a clinical dual-source PCD-CT scanner. Images were acquired with a tube voltage of 120 kV and using a collimation of 120 × 0.2 mm. Gantry rotation time was 0.25 seconds. Each scan was reconstructed using both single-source and dual-source data resulting in an image temporal resolution of 125 milliseconds and 66 milliseconds, respectively. The average heart rate and the heart rate variability were recorded. Images were reconstructed with a slice thickness of 0.2 mm, quantum iterative reconstruction strength level 4, and using the Bv64 and Bv72 kernel for patients without and with coronary stents, respectively. For subjective image quality, 2 experienced readers rated motion artifacts and vessel delineation, or in-stent lumen visualization using 5-point discrete visual scales. For objective image quality, signal-to-noise ratio, contrast-to-noise ratio, stent blooming artifacts, and vessel and stent sharpness were quantified. RESULTS Fifteen patients had coronary stents, and 15 patients had no coronary stents. The mean heart rate and heart rate variability during data acquisition were 72 ± 10 beats per minute and 5 ± 6 beats per minute, respectively. Subjective image quality in the right coronary artery, left anterior descending, and circumflex artery was significantly superior in 66 milliseconds reconstructions compared with 125 milliseconds reconstructions for both readers (all P 's < 0.01; interreader agreement, Krippendorff α = 0.84-1.00). Subjective image quality deteriorated significantly at higher heart rates for 125 milliseconds (ρ = 0.21, P < 0.05) but not for 66 milliseconds reconstructions (ρ = 0.11, P = 0.22). No association was found between heart rate variability and image quality for both 125 milliseconds (ρ = 0.09, P = 0.33) and 66 milliseconds reconstructions (ρ = 0.13, P = 0.17), respectively. Signal-to-noise ratio and contrast-to-noise ratio were similar between 66 milliseconds and 125 milliseconds reconstructions (both P 's > 0.05), respectively. Stent blooming artifacts were significantly lower on 66 milliseconds than on 125 milliseconds reconstructions (46.7% ± 10% vs 52.9% ± 8.9%, P < 0.001). Higher sharpness was found in 66 milliseconds than in 125 milliseconds reconstructions both in native coronary arteries (left anterior descending artery: 1031 ± 265 ∆HU/mm vs 819 ± 253 ∆HU/mm, P < 0.01; right coronary artery: 884 ± 352 ∆HU/mm vs 654 ± 377 ∆HU/mm, P < 0.001) and stents (5318 ± 3874 ∆HU/mm vs 4267 ± 3521 ∆HU/mm, P < 0.001). CONCLUSIONS Coronary angiography with PCD-CT in the UHR mode profits considerably from a high temporal resolution, resulting in less motion artifacts, superior vessel delineation and in-stent lumen visualization, less stent blooming artifacts, and superior vessel and stent sharpness.
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Affiliation(s)
- Victor Mergen
- From the Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland (V.M., T.S., G.C., M.S., K.H., R.M., M.E., H.A.); Department of Radiological, Oncological, and Anatomopathological Sciences, Sapienza University of Rome, Rome, Italy (G.C.); Siemens Healthcare GmbH, Computed Tomography, Forchheim, Germany (T.A., B.S., T.F.); and Institute of Radiology, Spitäler fmi AG, Spital Interlaken, Unterseen, Switzerland (M.E.)
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10
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Liang H, Du S, Yan G, Zhou Y, Yang T, Zhang Z, Luo C, Liao H, Li Y. Dual-energy CT of the pancreas: comparison between virtual non-contrast images and true non-contrast images in the detection of pancreatic lesion. Abdom Radiol (NY) 2023; 48:2596-2603. [PMID: 37210407 DOI: 10.1007/s00261-023-03914-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 04/07/2023] [Accepted: 04/10/2023] [Indexed: 05/22/2023]
Abstract
PURPOSE To evaluate the image quality and diagnostic performance for pancreatic lesion between true non-contrast (TNC) and virtual non-contrast (VNC) images obtained from the dual-energy computed tomography (DECT). METHODS One hundred six patients with pancreatic mass underwent contrast-enhanced DECT examinations were retrospectively included in this study. VNC images of the abdomen were generated from late arterial (aVNC) and portal (pVNC) phases. For quantitative analysis, the attenuation differences and reproducibility of abdominal organs were compared between TNC and aVNC/pVNC measurements. Qualitatively image quality was assessed by two radiologists using a five-point scale, and they independently compared the detection accuracy of pancreatic lesions between TNC and aVNC/pVNC images. The volume CT dose index (CTDIvol) and size-specific dose estimates (SSDE) were recorded to evaluate the potential dose reduction when using VNC reconstruction to replace the unenhanced phase. RESULTS A total of 78.38% (765/976) of the attenuation measurement pairs were reproducible between TNC and aVNC images, and 71.0% (693/976) between TNC and pVNC images. In triphasic examinations, a total of 108 pancreatic lesions were found in 106 patients, and no significant difference in detection accuracy was found between TNC and VNC images (p = 0.587-0.957). Qualitatively, image quality was rated diagnostic (score ≥ 3) in all the VNC images. Calculated CTDIvol and SSDE reduction of about 34% could be achieved by omitting the non-contrast phase. CONCLUSION VNC images of DECT provide diagnostic image quality and accurate pancreatic lesions detection, which are a promising alternative to unenhanced phase with a substantial reduction of radiation exposure in clinical routine.
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Affiliation(s)
- Hongwei Liang
- Department of Radiology, The First Affiliated Hospital of Chongqing Medical University, No. 1 Youyi Road, Yuzhong District, Chongqing, 400016, China
| | - Silin Du
- Department of Radiology, The First Affiliated Hospital of Chongqing Medical University, No. 1 Youyi Road, Yuzhong District, Chongqing, 400016, China
| | - Gaowu Yan
- Department of Radiology, Suining Central Hospital, Suining, 629000, China
| | - Yang Zhou
- Department of Radiology, The First Affiliated Hospital of Chongqing Medical University, No. 1 Youyi Road, Yuzhong District, Chongqing, 400016, China
| | - Tianyu Yang
- Department of Nuclear Medicine, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, China
| | - Zhiwei Zhang
- Department of Radiology, The First Affiliated Hospital of Chongqing Medical University, No. 1 Youyi Road, Yuzhong District, Chongqing, 400016, China
| | - Chenyi Luo
- Department of Radiology, The First Affiliated Hospital of Chongqing Medical University, No. 1 Youyi Road, Yuzhong District, Chongqing, 400016, China
| | - Hongfan Liao
- Department of Radiology, The First Affiliated Hospital of Chongqing Medical University, No. 1 Youyi Road, Yuzhong District, Chongqing, 400016, China
| | - Yongmei Li
- Department of Radiology, The First Affiliated Hospital of Chongqing Medical University, No. 1 Youyi Road, Yuzhong District, Chongqing, 400016, China.
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Alizadeh LS, Vogl TJ, Waldeck SS, Overhoff D, D'Angelo T, Martin SS, Yel I, Gruenewald LD, Koch V, Fulisch F, Booz C. Dual-Energy CT in Cardiothoracic Imaging: Current Developments. Diagnostics (Basel) 2023; 13:2116. [PMID: 37371011 DOI: 10.3390/diagnostics13122116] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 05/31/2023] [Accepted: 06/12/2023] [Indexed: 06/29/2023] Open
Abstract
This article describes the technical principles and clinical applications of dual-energy computed tomography (DECT) in the context of cardiothoracic imaging with a focus on current developments and techniques. Since the introduction of DECT, different vendors developed distinct hard and software approaches for generating multi-energy datasets and multiple DECT applications that were developed and clinically investigated for different fields of interest. Benefits for various clinical settings, such as oncology, trauma and emergency radiology, as well as musculoskeletal and cardiovascular imaging, were recently reported in the literature. State-of-the-art applications, such as virtual monoenergetic imaging (VMI), material decomposition, perfused blood volume imaging, virtual non-contrast imaging (VNC), plaque removal, and virtual non-calcium (VNCa) imaging, can significantly improve cardiothoracic CT image workflows and have a high potential for improvement of diagnostic accuracy and patient safety.
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Affiliation(s)
- Leona S Alizadeh
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, 60590 Frankfurt, Germany
- Division of Experimental Imaging, Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, 60590 Frankfurt, Germany
- Department of Diagnostic and Interventional Radiology, Bundeswehrzentralkrankenhaus Koblenz, 56072 Koblenz, Germany
| | - Thomas J Vogl
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, 60590 Frankfurt, Germany
| | - Stephan S Waldeck
- Department of Diagnostic and Interventional Radiology, Bundeswehrzentralkrankenhaus Koblenz, 56072 Koblenz, Germany
- Department of Diagnostic and Interventional Radiology, University Hospital Mainz, 55131 Mainz, Germany
| | - Daniel Overhoff
- Department of Diagnostic and Interventional Radiology, Bundeswehrzentralkrankenhaus Koblenz, 56072 Koblenz, Germany
- Department of Diagnostic and Interventional Radiology, University Hospital Mannheim, 68167 Mannheim, Germany
| | - Tommaso D'Angelo
- Diagnostic and Interventional Radiology Unit, Department of Biomedical Sciences and Morphological and Functional Imaging, "G. Martino" University Hospital Messina, 98124 Messina, Italy
| | - Simon S Martin
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, 60590 Frankfurt, Germany
- Division of Experimental Imaging, Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, 60590 Frankfurt, Germany
| | - Ibrahim Yel
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, 60590 Frankfurt, Germany
- Division of Experimental Imaging, Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, 60590 Frankfurt, Germany
| | - Leon D Gruenewald
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, 60590 Frankfurt, Germany
- Division of Experimental Imaging, Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, 60590 Frankfurt, Germany
| | - Vitali Koch
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, 60590 Frankfurt, Germany
- Division of Experimental Imaging, Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, 60590 Frankfurt, Germany
| | - Florian Fulisch
- Department of Diagnostic and Interventional Radiology, Bundeswehrzentralkrankenhaus Koblenz, 56072 Koblenz, Germany
| | - Christian Booz
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, 60590 Frankfurt, Germany
- Division of Experimental Imaging, Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, 60590 Frankfurt, Germany
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12
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Viltužnik R, Kaučič A, Blinc A, Vidmar J, Serša I. Comparing CT and MR Properties of Artificial Thrombi According to Their Composition. Diagnostics (Basel) 2023; 13:diagnostics13101802. [PMID: 37238289 DOI: 10.3390/diagnostics13101802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2023] [Revised: 05/09/2023] [Accepted: 05/16/2023] [Indexed: 05/28/2023] Open
Abstract
This study aims to determine whether and to what extent the structure and composition of thrombi can be assessed using NMR and CT measurements. Seven different thrombus models, namely, six RBC thrombi with hematocrit levels (HTs) of 0%, 20%, 40%, 60%, 80% and 100% and one platelet thrombus model, were analyzed using proton NMR at 100 MHz and 400 MHz, with measurements of T1 and T2 NMR relaxation times and measurements of the apparent diffusion coefficient (ADC). In addition, the thrombus models were CT-scanned in a dual-energy mode (80 kV and 140 kV) and in a single-energy mode (80 kV) to measure their CT numbers. The results confirmed that RBC thrombi can be distinguished from platelet thrombi by using ADC and CT number measurements in all three settings, while they cannot be distinguished by using T1 and T2 measurements. All measured parameters allowed for the differentiation of RBC thrombi according to their HT values, but the best sensitivity to HT was obtained with ADC and single-energy CT measurements. The importance of this study also lies in the potential application of its results for the characterization of actual thrombi in vivo.
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Affiliation(s)
- Rebeka Viltužnik
- Jožef Stefan Institute, 1000 Ljubljana, Slovenia
- Institute of Physiology, Faculty of Medicine, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Aleš Kaučič
- Clinical Institute of Radiology, University Medical Centre Ljubljana, 1000 Ljubljana, Slovenia
| | - Aleš Blinc
- Department of Vascular Diseases, University Medical Centre Ljubljana, 1000 Ljubljana, Slovenia
- Division of Internal Medicine, Faculty of Medicine, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Jernej Vidmar
- Jožef Stefan Institute, 1000 Ljubljana, Slovenia
- Institute of Physiology, Faculty of Medicine, University of Ljubljana, 1000 Ljubljana, Slovenia
- Clinical Institute of Radiology, University Medical Centre Ljubljana, 1000 Ljubljana, Slovenia
| | - Igor Serša
- Jožef Stefan Institute, 1000 Ljubljana, Slovenia
- Institute of Anatomy, Faculty of Medicine, University of Ljubljana, 1000 Ljubljana, Slovenia
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Estler A, Nikolaou K, Schönberg SO, Bamberg F, Froelich MF, Tollens F, Verloh N, Weiss J, Horger M, Hagen F. Is There Still a Role for Two-Phase Contrast-Enhanced CT and Virtual Monoenergetic Images in the Era of Photon-Counting Detector CT? Diagnostics (Basel) 2023; 13:diagnostics13081454. [PMID: 37189555 DOI: 10.3390/diagnostics13081454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 04/14/2023] [Accepted: 04/16/2023] [Indexed: 05/17/2023] Open
Abstract
BACKGROUND To compare the diagnostic characteristics between arterial phase imaging versus portal venous phase imaging, applying polychromatic T3D images and low keV virtual monochromatic images using a 1st generation photon-counting CT detector, of CT in patients with hepatocellular carcinoma (HCC). METHODS Consecutive patients with HCC, with a clinical indication for CT imaging, were prospectively enrolled. Virtual monoenergetic images (VMI) were reconstructed at 40 to 70 keV for the PCD-CT. Two independent, blinded radiologists counted all hepatic lesions and quantified their size. The lesion-to-background ratio was quantified for both phases. SNR and CNR were determined for T3D and low VMI images; non-parametric statistics were used. RESULTS Among 49 oncologic patients (mean age 66.9 ± 11.2 years, eight females), HCC was detected in both arterial and portal venous scans. The signal-to-noise ratio, the CNR liver-to-muscle, the CNR tumor-to-liver, and CNR tumor-to-muscle were 6.58 ± 2.86, 1.40 ± 0.42, 1.13 ± 0.49, and 1.53 ± 0.76 in the arterial phase and 5.93 ± 2.97, 1.73 ± 0.38, 0.79 ± 0.30, and 1.36 ± 0.60 in the portal venous phase with PCD-CT, respectively. There was no significant difference in SNR between the arterial and portal venous phases, including between "T3D" and low keV images (p > 0.05). CNRtumor-to-liver differed significantly between arterial and portal venous contrast phases (p < 0.005) for both "T3D" and all reconstructed keV levels. CNRliver-to-muscle and CNRtumor-to-muscle did not differ in either the arterial or portal venous contrast phases. CNRtumor-to-liver increased in the arterial contrast phase with lower keV in addition to SD. In the portal venous contrast phase, CNRtumor-to-liver decreased with lower keV; whereas, CNRtumor-to-muscle increased with lower keV in both arterial and portal venous contrast phases. CTDI and DLP mean values for the arterial upper abdomen phase were 9.03 ± 3.59 and 275 ± 133, respectively. CTDI and DLP mean values for the abdominal portal venous phase were 8.75 ± 2.99 and 448 ± 157 with PCD-CT, respectively. No statistically significant differences were found concerning the inter-reader agreement for any of the (calculated) keV levels in either the arterial or portal-venous contrast phases. CONCLUSIONS The arterial contrast phase imaging provides higher lesion-to-background ratios of HCC lesions using a PCD-CT; especially, at 40 keV. However, the difference was not subjectively perceived as significant.
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Affiliation(s)
- Arne Estler
- Department of Diagnostic and Interventional Radiology, University of Tuebingen, Hoppe-Seyler-Str. 3, 72076 Tuebingen, Germany
| | - Konstantin Nikolaou
- Department of Diagnostic and Interventional Radiology, University of Tuebingen, Hoppe-Seyler-Str. 3, 72076 Tuebingen, Germany
| | - Stefan O Schönberg
- Department of Radiology and Nuclear Medicine, University Medical Centre Mannheim, Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany
| | - Fabian Bamberg
- Department of Diagnostic and Interventional Radiology, Medical Center University of Freiburg, 79106 Freiburg, Germany
| | - Matthias F Froelich
- Department of Radiology and Nuclear Medicine, University Medical Centre Mannheim, Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany
| | - Fabian Tollens
- Department of Radiology and Nuclear Medicine, University Medical Centre Mannheim, Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany
| | - Niklas Verloh
- Department of Diagnostic and Interventional Radiology, Medical Center University of Freiburg, 79106 Freiburg, Germany
| | - Jakob Weiss
- Department of Diagnostic and Interventional Radiology, Medical Center University of Freiburg, 79106 Freiburg, Germany
| | - Marius Horger
- Department of Diagnostic and Interventional Radiology, University of Tuebingen, Hoppe-Seyler-Str. 3, 72076 Tuebingen, Germany
| | - Florian Hagen
- Department of Diagnostic and Interventional Radiology, University of Tuebingen, Hoppe-Seyler-Str. 3, 72076 Tuebingen, Germany
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14
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Yang C, Yin J, Wu L, Zeng Q, Zhang L. Research on the Identification Mechanism of Coal Gangue Based on the Differences of Mineral Components. ACS OMEGA 2023; 8:48-55. [PMID: 36643562 PMCID: PMC9835535 DOI: 10.1021/acsomega.2c05743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Accepted: 12/05/2022] [Indexed: 06/17/2023]
Abstract
For coal and gangue, intelligent sorting processes for separation, the use of coal and gangue mineral components with different fundamental differences, and the study of different properties of minerals and coal with different scales and density regarding the gray value change law are presented. The results show that the gray value of single minerals and mixed minerals gradually decreases with the increase of their thickness and density. The greater the density of minerals, the smaller the gray value at the same thickness, and the same rule applies to different coal ranks. Via regression analysis methods, the values of the regression equation parameter a of pure minerals for graphite, quartz, kaolinite, and montmorillonite are 59.25, 65.69, 61.61, and 58.02 in the high-energy region, respectively. In the low-energy region, they are 174.95, 177.31, 186.95, and 161.81. For the regression equation parameter of mixed minerals in the form of two mixed minerals (graphite and quartz, kaolinite, or montmorillonite) and three kinds of mineral mixing (graphite-kaolinite and quartz; graphite-montmorillonite and quartz; graphite-kaolinite and montmorillonite), the gray values are 151.12, 156.00, 153.13,152.43, 152.98, and 151.98 in the high-energy region, respectively; in the low-energy region, they are 193.34, 201.34, 192.93, 191.26, 194.68, and 193.08. The phenomenon for the gray range of two kinds of single minerals locates in the range of mixed minerals that was formed from a single mineral observed after the regression equation of mixed mineral was verified by a single mineral, which agrees with the X-ray recognition pattern. In the end, as the density of coking coal, fat coal, and gas coal increases, the gray value decreases, which was in agreement with single- and mixed-mineral analyses.
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15
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Zhou Z, Gao Y, Zhang W, Bo K, Zhang N, Wang H, Wang R, Du Z, Firmin D, Yang G, Zhang H, Xu L. Artificial intelligence-based full aortic CT angiography imaging with ultra-low-dose contrast medium: a preliminary study. Eur Radiol 2023; 33:678-689. [PMID: 35788754 DOI: 10.1007/s00330-022-08975-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Revised: 05/16/2022] [Accepted: 06/20/2022] [Indexed: 11/29/2022]
Abstract
OBJECTIVES To further reduce the contrast medium (CM) dose of full aortic CT angiography (ACTA) imaging using the augmented cycle-consistent adversarial framework (Au-CycleGAN) algorithm. METHODS We prospectively enrolled 150 consecutive patients with suspected aortic disease. All received ACTA scans of ultra-low-dose CM (ULDCM) protocol and low-dose CM (LDCM) protocol. These data were randomly assigned to the training datasets (n = 100) and the validation datasets (n = 50). The ULDCM images were reconstructed by the Au-CycleGAN algorithm. Then, the AI-based ULDCM images were compared with LDCM images in terms of image quality and diagnostic accuracy. RESULTS The mean image quality score of each location in the AI-based ULDCM group was higher than that in the ULDCM group but a little lower than that in the LDCM group (all p < 0.05). All AI-based ULDCM images met the diagnostic requirements (score ≥ 3). Except for the image noise, the AI-based ULDCM images had higher attenuation value than the ULDCM and LDCM images as well as higher SNR and CNR in all locations of the aorta analyzed (all p < 0.05). Similar results were also seen in obese patients (BMI > 25, all p < 0.05). Using the findings of LDCM images as the reference, the AI-based ULDCM images showed good diagnostic parameters and no significant differences in any of the analyzed aortic disease diagnoses (all K-values > 0.80, p < 0.05). CONCLUSIONS The required dose of CM for full ACTA imaging can be reduced to one-third of the CM dose of the LDCM protocol while maintaining image quality and diagnostic accuracy using the Au-CycleGAN algorithm. KEY POINTS • The required dose of contrast medium (CM) for full ACTA imaging can be reduced to one-third of the CM dose of the low-dose contrast medium (LDCM) protocol using the Au-CycleGAN algorithm. • Except for the image noise, the AI-based ultra-low-dose contrast medium (ULDCM) images had better quantitative image quality parameters than the ULDCM and LDCM images. • No significant diagnostic differences were noted between the AI-based ULDCM and LDCM images regarding all the analyzed aortic disease diagnoses.
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Affiliation(s)
- Zhen Zhou
- Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, No. 2, Anzhen Road, Chaoyang District, Beijing, 100029, China
| | - Yifeng Gao
- Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, No. 2, Anzhen Road, Chaoyang District, Beijing, 100029, China
| | - Weiwei Zhang
- School of Biomedical Engineering, Sun Yat-Sen University, Guangzhou, China
| | - Kairui Bo
- Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, No. 2, Anzhen Road, Chaoyang District, Beijing, 100029, China
| | - Nan Zhang
- Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, No. 2, Anzhen Road, Chaoyang District, Beijing, 100029, China
| | - Hui Wang
- Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, No. 2, Anzhen Road, Chaoyang District, Beijing, 100029, China
| | - Rui Wang
- Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, No. 2, Anzhen Road, Chaoyang District, Beijing, 100029, China
| | - Zhiqiang Du
- Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, No. 2, Anzhen Road, Chaoyang District, Beijing, 100029, China
| | - David Firmin
- Cardiovascular Research Centre, Royal Brompton Hospital, London, SW3 6NP, UK.,National Heart and Lung Institute, Imperial College London, London, SW7 2AZ, UK
| | - Guang Yang
- Cardiovascular Research Centre, Royal Brompton Hospital, London, SW3 6NP, UK.,National Heart and Lung Institute, Imperial College London, London, SW7 2AZ, UK
| | - Heye Zhang
- School of Biomedical Engineering, Sun Yat-Sen University, Guangzhou, China
| | - Lei Xu
- Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, No. 2, Anzhen Road, Chaoyang District, Beijing, 100029, China.
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Meng Q, Li J, Jiang W, Hu B, Xu F, Shi X, Zhong R. Prediction of proton beam range in phantom with metals based on monochromatic energy CT images. JOURNAL OF RADIATION RESEARCH 2022; 63:828-837. [PMID: 36109316 PMCID: PMC9726739 DOI: 10.1093/jrr/rrac051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 05/30/2022] [Indexed: 06/15/2023]
Abstract
The purpose of the study was to evaluate the accuracy of monochromatic energy (MonoE) computed tomography (CT) images reconstructed by spectral CT in predicting the stopping power ratio $( SP{R}_w)$ of materials in the presence of metal. The CIRS062 phantom was scanned three times using spectral CT. In the first scan, a solid water insert was placed at the center of the phantom $(C{T}_{no\ metal})$. In the second scan, the solid water insert was replaced with a titanium alloy femoral head $(C{T}_{metal})$. The metal artifact reduction (MAR) algorithm was used in the last scan $(C{T}_{metal+ MAR})$. The MonoE-CT images of 40 keV and 80 keV were reconstructed. Finally, the single-energy CT method (SECT) and the dual-energy CT method (DECT) were used to calculate the $SP{R}_w$. The mean absolute error (MAE) of the $SP{R}_w$ of the inner layer inserts calculated by the SECT method were 3.19%, 13.88% and 2.71%, corresponding to $C{T}_{no\ metal}$, $C{T}_{metal}$ and $C{T}_{metal+ MAR}$, respectively. For the outer layer inserts, the MAE of $SP{R}_w$ were 3.43%, 5.42% and 2.99%, respectively. Using the DECT method, the MAE of the $SP{R}_w$ of the inner layer inserts was 1.30%, 3.69% and 1.46% and the MAE of the outer layer inserts- was 1.34%, 1.36% and 1.05%. The studies shows that, compared with the SECT method, the accuracy of the DECT method in predicting the $SP{R}_w$ of a material is more robust to the presence of metal. Using the MAR algorithm when performing CT scans can further improve the accuracy of predicting the SPR of materials in the presence of metal.
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Affiliation(s)
- Qianqian Meng
- Radiophysical Technology Center, Cancer Center, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Jing Li
- Radiophysical Technology Center, Cancer Center, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Wei Jiang
- Department of Radiotherapy, Yantai Yuhuangding Hospital, Yantai, 264000, China
- Academy of Medical Engineering and Translational Medicine, Department of Biomedical Engineering, School of Precision Instrument and Opto-electronics Engineering, Tianjin University, Tianjin, 300072, China
| | - Birong Hu
- Department of Radiotherapy, Chengdu Second People’s Hospital, Chengdu, 610021, China
| | - Feng Xu
- Lung Cancer Center & Institute, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Xiaomeng Shi
- CT Imaging Research Center, GE Healthcare China, Shanghai, 201203, China
| | - Renming Zhong
- Corresponding author. Department of Radiotherapy, Division of Radiation Physics, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu 610041, P.R. China. Tel: +8628-85422568, E-mail:
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Itoh T, Noguchi K. Evaluation of the quantitative performance of non-enhanced dual-energy CT X-map in detecting acute ischemic brain stroke: A model observer study using computer simulation. Phys Med 2022; 104:85-92. [PMID: 36371946 DOI: 10.1016/j.ejmp.2022.10.025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 09/02/2022] [Accepted: 10/30/2022] [Indexed: 11/11/2022] Open
Abstract
PURPOSE A simulation study was performed to evaluate the quantitative performance of X-map images-derived from non-enhanced (NE) dual-energy computed tomography (DECT)-in detecting acute ischemic stroke (AIS) compared with that of NE-DECT mixed images. METHODS A virtual phantom, 150 mm in diameter, filled with tissues comprising various gray- and white-matter proportions was used to generate pairs of NE-head images at 80 kV and Sn150 kV at three dose levels (20, 40, and 60 mGy). The phantom included an inserted low-contrast object, 15 mm in diameter, with four densities (0%, 5%, 10%, and 15%) mimicking ischemic edema. Mixed and X-map images were generated from these sets of images and compared in terms of detectability of ischemic edema using a channelized Hotelling observer (CHO). The area under the curve (AUC) of the receiver operating characteristic that generated CHO for each condition was used as a figure of merit. RESULTS The AUCs of X-map images were always significantly higher than those of mixed images (P < 0.001). The improvement in AUC for X-map images compared with that for mixed images at edema densities was 9.2%-12.6% at 20 mGy, 10.1%-17.7% at 40 mGy, and 14.0%-19.4% at 60 mGy. At any edema density, X-map images at 20 mGy resulted in higher AUCs than mixed images acquired at any other dose level (P < 0.001), which corresponded to a 66% dose reduction on X-map images. CONCLUSIONS The simulation study confirmed that NE-DECT X-map images have superior capability of detecting AIS than NE-DECT mixed images.
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Affiliation(s)
- Toshihide Itoh
- Department of CT Research and Collaboration, Siemens Healthineers, 1-11-1 Osaki, Shinagawa, Tokyo 141-8644, Japan.
| | - Kyo Noguchi
- Department of Radiology, Graduate School of Medicine and Pharmaceutical Science, University of Toyama, 2630 Sugitani, Toyama city, Toyama 930-0194, Japan
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Gao XG, Sha JF, Luan JY, Li MC, Wang JP. A triple-source CT system for micro-scale investigation of geological materials: A simulation study. Appl Radiat Isot 2022; 190:110510. [DOI: 10.1016/j.apradiso.2022.110510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 10/05/2022] [Accepted: 10/05/2022] [Indexed: 11/15/2022]
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19
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Li G, Xie Y, Xu B. Three-dimensional reconstruction with dual-source computed tomography for evaluating graft deformation and bone tunnel position following reconstruction of the anterior cruciate ligament. Med Eng Phys 2022; 110:103858. [PMID: 35909023 DOI: 10.1016/j.medengphy.2022.103858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 06/23/2022] [Accepted: 07/22/2022] [Indexed: 01/18/2023]
Abstract
OBJECTIVE Considering the limitations of MRI and X-ray and few studies on the use of dual-source computed tomography (DSCT) in anterior cruciate ligament (ACL) reconstruction are limited, this study explored the clinical application of DSCT for three-dimensional reconstruction of graft deformation and bone tunnel position images following ACL reconstruction. METHODS The data of 123 patients who underwent single-bundle ACL reconstruction under arthroscopy from January 2017 to October 2021 were retrieved. Two weeks after surgery, DSCT was used to assess graft deformation and tunnel widening. Based on the positions of ACL graft deformation and bone tunnel, the patients were divided into a collision group (n = 35), posterior group (n = 37) and satisfactory group (n = 51). The groups were compared in terms of the relative position of the central point of the femoral tunnel (FX, FY) and tibial tunnel (TX, TY), the straight-line distances of the grafts (L), the sagittal plane angle (∠α), and the coronal plane angle (∠β) between the two bone tunnels. RESULTS Tx, Ty, ∠α and ∠β were significantly different among the three groups, while no difference in Fx, Fy and L were observed. Tx, Ty and ∠α were identified as independent risk factors for collisions between the graft and intercondylar notch. Ty and ∠α were independent risk factors for posterior deviation of tibial tunnel position. CONCLUSION DSCT demonstrated promising clinical applicability to evaluate graft deformation and bone tunnel position after reconstruction of ACL and could guide preoperative positioning and postoperative evaluation.
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Affiliation(s)
- Guangzheng Li
- Department of Orthopedics, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, 230022, China; Department of Orthopedics, Maanshan People's Hospital, Ma'anshan, Anhui, 243099, China.
| | - Yang Xie
- Department of Orthopedics, Maanshan People's Hospital, Ma'anshan, Anhui, 243099, China
| | - Bin Xu
- Department of Orthopedics, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, 230022, China.
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Multivendor Comparison of Quantification Accuracy of Iodine Concentration and Attenuation Measurements by Dual-Energy CT: A Phantom Study. AJR Am J Roentgenol 2022; 219:827-839. [PMID: 35674353 DOI: 10.2214/ajr.22.27753] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND. Studies comparing accuracy of quantification by dual-energy CT (DECT) scanners have been limited by small numbers of scanners evaluated and narrow ranges of scanning conditions. OBJECTIVE. The purpose of this study was to compare DECT scanners of varying vendors, technologies, and generations in terms of the accuracy of iodine concentration and attenuation measurements. METHODS. A DECT quality-control phantom was designed to contain seven inserts of varying iodine concentrations as well as soft-tissue and fat inserts. The phantom underwent DECT using 12 different scanner configurations based on seven different DECT scanners from three vendors, with additional variation in tube voltage settings. Technologies included rapid-switching, dual-source, and dual-layer detector DECT. Scans also used three radiation dose levels (10, 20, and 30 mGy) and multiple reconstruction algorithms (filtered back projection, medium and high iterative reconstruction, and deep learning image reconstruction [DLIR]). The mean absolute percentage error (MAPE, representing the absolute ratio of measured error to nominal values on average; lower values indicate better accuracy) was calculated for iodine concentration on iodine maps (MAPEiodine) and attenuation on virtual monochromatic images (VMIs) using 40, 70, 100, and 140 keV (MAPEHU). Linear mixed models were used to explore factors affecting quantification accuracy. RESULTS. MAPEiodine and MAPEHU ranged 4.62-28.55% and 10.21-26.33%, respectively, across scanner configurations. Accuracies of iodine concentration and attenuation measurements were higher for third-generation rapid-switching and dual-source scanners in comparison with respective earlier-generation scanners and the single evaluated dual-layer detector scanner. Among all configurations, the third-generation rapid-switching scanner using DLIR had the highest quantification accuracy for iodine concentration (MAPEiodine, 4.62% ± 3.87%) and attenuation (MAPEHU, 10.21% ± 11.43%). Overall, MAPEiodine was significantly affected by scanner configuration (F = 450.0, p < .001) and iodine concentration (F = 211.0, p < .001). Overall, MAPEHU was significantly affected by scanner configuration (F = 233.5, p < .001), radiation dose (F = 14.9, p < .001), VMI energy level (F = 1959.4, p < .001), and material density (F = 411.5, p < .001); radiation dose was significantly associated with MAPEHU for five of 12 individual configurations. CONCLUSION. Quantification accuracy varied among DECT configurations of varying vendors, platforms, and generations and was affected by acquisition and reconstruction parameters. DLIR may improve quantification accuracy. CLINICAL IMPACT. The interscanner differences in DECT-based measurements should be recognized when quantitative evaluation is performed by DECT in clinical practice.
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Li Y, Younis MH, Wang H, Zhang J, Cai W, Ni D. Spectral computed tomography with inorganic nanomaterials: State-of-the-art. Adv Drug Deliv Rev 2022; 189:114524. [PMID: 36058350 PMCID: PMC9664656 DOI: 10.1016/j.addr.2022.114524] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 08/09/2022] [Accepted: 08/27/2022] [Indexed: 01/24/2023]
Abstract
Recently, spectral computed tomography (CT) technology has received great interest in the field of radiology. Spectral CT imaging utilizes the distinct, energy-dependent X-ray absorption properties of substances in order to provide additional imaging information. Dual-energy CT and multi-energy CT (Spectral CT) are capable of constructing monochromatic energy images, material separation images, energy spectrum curves, constructing effective atomic number maps, and more. However, poor contrast, due to neighboring X-ray attenuation of organs and tissues, is still a challenge to spectral CT. Hence, contrast agents (CAs) are applied for better differentiation of a given region of interest (ROI). Currently, many different kinds of inorganic nanoparticulate CAs for spectral CT have been developed due to the limitations of clinical iodine (I)-based contrast media, leading to the conclusion that inorganic nanomedicine applied to spectral CT will be a powerful collaboration both in basic research and in clinics. In this review, the underlying principles and types of spectral CT techniques are discussed, and some evolving clinical diagnosis applications of spectral CT techniques are introduced. In particular, recent developments in inorganic CAs used for spectral CT are summarized. Finally, the challenges and future developments of inorganic nanomedicine in spectral CT are briefly discussed.
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Affiliation(s)
- Yuhan Li
- School of Medicine, Shanghai University, No. 99 Shangda Rd, Shanghai 200444, PR China
| | - Muhsin H Younis
- Departments of Radiology and Medical Physics, University of Wisconsin-Madison, WI 53705, United States
| | - Han Wang
- Department of Orthopaedics, Shanghai Key Laboratory for Prevention and Treatment of Bone and Joint Diseases, Shanghai Institute of Traumatology and Orthopaedics, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, No. 197, Ruijin 2nd Rd, Shanghai 200025, PR China
| | - Jian Zhang
- School of Medicine, Shanghai University, No. 99 Shangda Rd, Shanghai 200444, PR China; Shanghai Universal Medical Imaging Diagnostic Center, Bldg 8, No. 406 Guilin Rd, Shanghai 200233, PR China.
| | - Weibo Cai
- Departments of Radiology and Medical Physics, University of Wisconsin-Madison, WI 53705, United States.
| | - Dalong Ni
- Department of Orthopaedics, Shanghai Key Laboratory for Prevention and Treatment of Bone and Joint Diseases, Shanghai Institute of Traumatology and Orthopaedics, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, No. 197, Ruijin 2nd Rd, Shanghai 200025, PR China.
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22
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Bharati A, Rani Mandal S, Gupta AK, Seth A, Sharma R, Bhalla AS, Das CJ, Chatterjee S, Kumar P. Non-Invasive characterisation of renal stones using dual energy CT: A method to differentiate calcium stones. Phys Med 2022; 101:158-164. [PMID: 36007404 DOI: 10.1016/j.ejmp.2022.08.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 06/22/2022] [Accepted: 08/17/2022] [Indexed: 10/15/2022] Open
Abstract
BACKGROUND Non-invasive DECT based characterization of renal stones using their effective atomic number (Zeff) and the electron density (ρe) in patients. AIM This paper aims to develop a method for in-vivo characterization of renal stone. Differentiation of renal stones in-vivo especially sub types of calcium stones have very important advantage for better judgement of treatment modality. MATERIALS AND METHODS 50 extracted renal stones were scanned ex-vivo using dual energy CT scanner. A method was developed to characterize these renal stones using effective atomic number and electron density obtained from dual energy CT data. The method and formulation developed in ex-vivo experiments was applied in in-vivo study of 50 randomly selected patients of renal stones who underwent dual energy CT scan. RESULTS The developed method was able to characterize Calcium Oxalate Monohydrate (COM) and the combination of COM and Calcium Oxalate Dihydrate (COD) stones non-invasively in patients with a sensitivity of 81% and 83%respectively. The method was also capable of differentiating Uric, Cystine and mixed stones with the sensitivity of 100, 100 and 85.71% respectively. CONCLUSION The developed dual energy CT based method was capable of differentiating sub types of calcium stones which is not differentiable on single energy or dual energy CT images.
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Affiliation(s)
- Avinav Bharati
- Department of Radiation Oncology, Dr. Ram Manohar Lohia Institute of Medical Sciences, Lucknow, Uttar Prades 226010, India
| | | | | | - Amlesh Seth
- Department of Urology, AIIMS, New Delhi 110029, India
| | - Raju Sharma
- Department of Radiodiagnosis, AIIMS, New Delhi 110029, India
| | - Ashu S Bhalla
- Department of Radiodiagnosis, AIIMS, New Delhi 110029, India
| | - Chandan J Das
- Department of Radiodiagnosis, AIIMS, New Delhi 110029, India
| | - Sabyasachi Chatterjee
- BGVS, Chemical Engineering Building (Old), Institute of Science, Bengaluru, Karnataka 560012,India
| | - Pratik Kumar
- Medical Physics Unit, IRCH, AIIMS, New Delhi 110029, India.
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Dual-source computed tomography protocols for the pediatric chest - scan optimization techniques. Pediatr Radiol 2022:10.1007/s00247-022-05468-7. [PMID: 35948645 PMCID: PMC9365683 DOI: 10.1007/s00247-022-05468-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 06/28/2022] [Accepted: 07/21/2022] [Indexed: 11/26/2022]
Abstract
The gold standard for pediatric chest imaging remains the CT scan. An ideal pediatric chest CT has the lowest radiation dose with the least motion degradation possible in a diagnostic scan. Because of the known inherent risks and costs of anesthesia, non-sedate options are preferred. Dual-source CTs are currently the fastest, lowest-dose CT scanners available, utilizing an ultra-high-pitch mode resulting in sub-second CTs. The dual-energy technique, available on dual-source CT scanners, gathers additional information such as pulmonary blood volume and includes relative contrast enhancement and metallic artifact reduction, features that are not available in high-pitch flash mode. In this article we discuss the benefits and tradeoffs of dual-source CT scan modes and tips on image optimization.
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Hagen F, Walder L, Fritz J, Gutjahr R, Schmidt B, Faby S, Bamberg F, Schoenberg S, Nikolaou K, Horger M. Image Quality and Radiation Dose of Contrast-Enhanced Chest-CT Acquired on a Clinical Photon-Counting Detector CT vs. Second-Generation Dual-Source CT in an Oncologic Cohort: Preliminary Results. Tomography 2022; 8:1466-1476. [PMID: 35736867 PMCID: PMC9227736 DOI: 10.3390/tomography8030119] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 05/14/2022] [Accepted: 05/30/2022] [Indexed: 11/16/2022] Open
Abstract
Our aim was to compare the image quality and patient dose of contrast-enhanced oncologic chest-CT of a first-generation photon-counting detector (PCD-CT) and a second-generation dual-source dual-energy CT (DSCT). For this reason, one hundred consecutive oncologic patients (63 male, 65 ± 11 years, BMI: 16−42 kg/m2) were prospectively enrolled and evaluated. Clinically indicated contrast-enhanced chest-CT were obtained with PCD-CT and compared to previously obtained chest-DSCT in the same individuals. The median time interval between the scans was three months. The same contrast media protocol was used for both scans. PCD-CT was performed in QuantumPlus mode (obtaining full spectral information) at 120 kVp. DSCT was performed using 100 kV for Tube A and 140 kV for Tube B. “T3D” PCD-CT images were evaluated, which emulate conventional 120 keV polychromatic images. For DSCT, the convolution algorithm was set at I31f with class 1 iterative reconstruction, whereas comparable Br40 kernel and iterative reconstruction strengths (Q1 and Q3) were applied for PCD-CT. Two radiologists assessed image quality using a five-point Likert scale and performed measurements of vessels and lung parenchyma for signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and in the case of pulmonary metastases tumor-to-lung parenchyma contrast ratio. PCD-CT CNRvessel was significantly higher than DSCT CNRvessel (all, p < 0.05). Readers rated image contrast of mediastinum, vessels, and lung parenchyma significantly higher in PCD-CT than DSCT images (p < 0.001). Q3 PCD-CT CNRlung_parenchyma was significantly higher than DSCT CNRlung_parenchyma and Q1 PCD-CT CNRlung_parenchyma (p < 0.01). The tumor-to-lung parenchyma contrast ratio was significantly higher on PCD-CT than DSCT images (0.08 ± 0.04 vs. 0.03 ± 0.02, p < 0.001). CTDI, DLP, SSDE mean values for PCD-CT and DSCT were 4.17 ± 1.29 mGy vs. 7.21 ± 0.49 mGy, 151.01 ± 48.56 mGy * cm vs. 288.64 ± 31.17 mGy * cm and 4.23 ± 0.97 vs. 7.48 ± 1.09, respectively. PCD-CT enables oncologic chest-CT with a significantly reduced dose while maintaining image quality similar to a second-generation DSCT for comparable protocol settings.
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Affiliation(s)
- Florian Hagen
- Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University, Hoppe-Seyler-Str. 3, 72070 Tübingen, Germany; (F.H.); (K.N.); (M.H.)
| | - Lukas Walder
- Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University, Hoppe-Seyler-Str. 3, 72070 Tübingen, Germany; (F.H.); (K.N.); (M.H.)
- Correspondence: ; Tel.: +49-07071-29-68622
| | - Jan Fritz
- NYU Grossman School of Medicine, Department of Radiology, New York, NY 10016, USA;
| | - Ralf Gutjahr
- Siemens Healthcare GmbH, 91052 Erlangen, Germany; (R.G.); (B.S.); (S.F.)
| | - Bernhard Schmidt
- Siemens Healthcare GmbH, 91052 Erlangen, Germany; (R.G.); (B.S.); (S.F.)
| | - Sebastian Faby
- Siemens Healthcare GmbH, 91052 Erlangen, Germany; (R.G.); (B.S.); (S.F.)
| | - Fabian Bamberg
- Department of Radiology, Albert-Ludwigs-University Freiburg, 79106 Freiburg, Germany;
| | - Stefan Schoenberg
- Department of Radiology, University of Mannheim, 68167 Mannheim, Germany;
| | - Konstantin Nikolaou
- Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University, Hoppe-Seyler-Str. 3, 72070 Tübingen, Germany; (F.H.); (K.N.); (M.H.)
| | - Marius Horger
- Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University, Hoppe-Seyler-Str. 3, 72070 Tübingen, Germany; (F.H.); (K.N.); (M.H.)
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25
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Hagen F, Hofmann J, Wrazidlo R, Gutjahr R, Schmidt B, Faby S, Nikolaou K, Horger M. Image quality and dose exposure of contrast-enhanced abdominal CT on a 1st generation clinical dual-source photon-counting detector CT in obese patients vs. a 2nd generation dual-source dual energy integrating detector CT. Eur J Radiol 2022; 151:110325. [DOI: 10.1016/j.ejrad.2022.110325] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 04/11/2022] [Accepted: 04/13/2022] [Indexed: 01/15/2023]
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Lee D, Yun S, Soh J, Lim S, Kim H, Cho S. A generalized simultaneous algebraic reconstruction technique (GSART) for dual-energy X-ray computed tomography. JOURNAL OF X-RAY SCIENCE AND TECHNOLOGY 2022; 30:549-566. [PMID: 35253722 DOI: 10.3233/xst-211054] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
BACKGROUND Dual-energy computed tomography (DECT) is a widely used and actively researched imaging modality that can estimate the physical properties of an object more accurately than single-energy CT (SECT). Recently, iterative reconstruction methods called one-step methods have received attention among various approaches since they can resolve the intermingled limitations of the conventional methods. However, the one-step methods typically have expensive computational costs, and their material decomposition performance is largely affected by the accuracy in the spectral coefficients estimation. OBJECTIVE In this study, we aim to develop an efficient one-step algorithm that can effectively decompose into the basis material maps and is less sensitive to the accuracy of the spectral coefficients. METHODS By use of a new loss function that employs the non-linear forward model and the weighted squared errors, we propose a one-step reconstruction algorithm named generalized simultaneous algebraic reconstruction technique (GSART). The proposed algorithm was compared with the image-domain material decomposition and other existing one-step reconstruction algorithm. RESULTS In both simulation and experimental studies, we demonstrated that the proposed algorithm effectively reduced the beam-hardening artifacts thereby increasing the accuracy in the material decomposition. CONCLUSIONS The proposed one-step reconstruction for material decomposition in dual-energy CT outperformed the image-domain approach and the existing one-step algorithm. We believe that the proposed method is a practically very useful addition to the material-selective image reconstruction field.
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Affiliation(s)
- Donghyeon Lee
- Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, Daejeon, Korea
| | - Sungho Yun
- Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, Daejeon, Korea
| | - Jeongtae Soh
- Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, Daejeon, Korea
| | - Sunho Lim
- Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, Daejeon, Korea
| | - Hyoyi Kim
- Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, Daejeon, Korea
| | - Seungryong Cho
- Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, Daejeon, Korea
- KAIST Institutes for ITC, AI, and HST, Korea Advanced Institute of Science and Technology, Daejeon, Korea
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Zhou Y, Hu L, Du S, Jin R, Li W, Lv F, Zhang Z. The ultrafast, high-pitch turbo FLASH mode of third-generation dual-source CT: Effect of different pitch and corresponding SFOV on image quality in a phantom study. J Appl Clin Med Phys 2021; 22:158-167. [PMID: 34752014 PMCID: PMC8664149 DOI: 10.1002/acm2.13466] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 10/13/2021] [Accepted: 10/18/2021] [Indexed: 12/15/2022] Open
Abstract
PURPOSE To investigate the effect of different pitches and corresponding scan fields of view (SFOVs) on the image quality in the ultrafast, high-pitch turbo FLASH mode of the third-generation dual-source CT using an anthropomorphic phantom. METHODS The phantom was scanned using the ultrafast, high-pitch turbo FLASH protocols of the third-generation dual-source CT with the different pitches and corresponding SFOVs (pitches: 1.55 to 3.2 with increments of 0.1, SFOVs: 50 cm to 35.4 cm). The objective parameters such as the CT number, image noises, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and artifacts index (AI), and image features from the head, chest, and abdomen were compared between the CT images with a pitch of 1.55 and SFOV of Ø 50 cm and a pitch of 3.2 and SFOV of Ø 35.4 cm. Then, the 18 series of CT images of the head, chest, and abdomen were evaluated by three radiologists independently. RESULTS The differences in the CT numbers were not statically significant between the CT images with a pitch of 1.55 and SFOV of Ø 50 cm and a pitch of 3.2 and SFOV of Ø 35.4 cm from most body parts and potential combinations (p > 0.05), Most of the image noises and the AI from the images with the pitch of 1.55 were significantly lower than those with the pitch of 3.2 (p < 0.05), and the SNR and CNR from the images with the pitch of 1.55 were higher than those with the pitch of 3.2. There were significant differences in the first-order features and texture features of the head (59.3%, 28.3%), chest (66%, 35.7%), and abdomen (71.6%, 64.7%) (p < 0.05). The subjective image quality was excellent when the pitch was less than 2.0 and gradually decreased with the increasing pitch. In addition, the image quality decreased significantly when the pitch was higher than 3.0 (all k≥0.69), especially in the head and chest. CONCLUSIONS In the ultrafast, high-pitch turbo FLASH mode of the third-generation DSCT, increasing the pitch and lowering the corresponding SFOV will change the image features and cause more artifacts degrading the image quality. Specific to the clinical needs, decreasing the pitch not only can expand the SFOV but also can improve the image quality.
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Affiliation(s)
- Yang Zhou
- Department of Radiology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Lei Hu
- Network Information Center, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Silin Du
- Department of Radiology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Rui Jin
- Department of Radiology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Wangjia Li
- Department of Radiology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Fajin Lv
- Department of Radiology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Zhiwei Zhang
- Department of Radiology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China
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Tarkowski P, Czekajska-Chehab E. Dual-Energy Heart CT: Beyond Better Angiography-Review. J Clin Med 2021; 10:jcm10215193. [PMID: 34768713 PMCID: PMC8584316 DOI: 10.3390/jcm10215193] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 11/02/2021] [Accepted: 11/04/2021] [Indexed: 12/30/2022] Open
Abstract
Heart CT has undergone substantial development from the use of calcium scores performed on electron beam CT to modern 256+-row CT scanners. The latest big step in its evolution was the invention of dual-energy scanners with much greater capabilities than just performing better ECG-gated angio-CT. In this review, we present the unique features of dual-energy CT in heart diagnostics.
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Zhang L, Li L, Feng G, Fan T, Jiang H, Wang Z. Advances in CT Techniques in Vascular Calcification. Front Cardiovasc Med 2021; 8:716822. [PMID: 34660718 PMCID: PMC8511450 DOI: 10.3389/fcvm.2021.716822] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Accepted: 08/30/2021] [Indexed: 12/17/2022] Open
Abstract
Vascular calcification, a common pathological phenomenon in atherosclerosis, diabetes, hypertension, and other diseases, increases the incidence and mortality of cardiovascular diseases. Therefore, the prevention and detection of vascular calcification play an important role. At present, various techniques have been applied to the analysis of vascular calcification, but clinical examination mainly depends on non-invasive and invasive imaging methods to detect and quantify. Computed tomography (CT), as a commonly used clinical examination method, can analyze vascular calcification. In recent years, with the development of technology, in addition to traditional CT, some emerging types of CT, such as dual-energy CT and micro CT, have emerged for vascular imaging and providing anatomical information for calcification. This review focuses on the latest application of various CT techniques in vascular calcification.
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Affiliation(s)
- Lijie Zhang
- Department of Cardiology, Affiliated Hospital of Jiangsu University, Zhenjiang, China
| | - Lihua Li
- Department of Pathology, Affiliated Hospital of Jiangsu University, Zhenjiang, China
| | - Guoquan Feng
- Department of Radiology, Affiliated Hospital of Jiangsu University, Zhenjiang, China
| | - Tingpan Fan
- Department of Cardiology, Affiliated Hospital of Jiangsu University, Zhenjiang, China
| | - Han Jiang
- Department of Cardiology, Affiliated Hospital of Jiangsu University, Zhenjiang, China
| | - Zhongqun Wang
- Department of Cardiology, Affiliated Hospital of Jiangsu University, Zhenjiang, China
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Editorial. Phys Med 2020; 79:ii-v. [DOI: 10.1016/j.ejmp.2020.11.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/20/2020] [Indexed: 11/20/2022] Open
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