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Hubbard L, Molloi S. Low-dose quantitative CT myocardial flow measurement using a single volume scan: phantom and animal validation. J Med Imaging (Bellingham) 2023; 10:056002. [PMID: 37915404 PMCID: PMC10617548 DOI: 10.1117/1.jmi.10.5.056002] [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: 03/06/2023] [Revised: 10/11/2023] [Accepted: 10/16/2023] [Indexed: 11/03/2023] Open
Abstract
Purpose To validate a low-dose, single-volume quantitative CT myocardial flow technique in a cardiovascular flow phantom and a swine animal model of coronary artery disease. Approach A cardiovascular flow phantom was imaged dynamically over different flow rates (0.97 to 2.45 mL / min / g ) using 15 mL of contrast per injection. Six swine (37 ± 8 kg ) were also imaged dynamically, with different left anterior descending coronary artery balloon stenoses assessed under intracoronary adenosine stress, using 1 mL / kg of contrast per injection. The resulting images were used to simulate dynamic bolus tracking and peak volume scan acquisition. After which, first-pass single-compartment modeling was performed to derive quantitative flow, where the pre-contrast myocardial attenuation was assumed to be spatially uniform. The accuracy of CT flow was then assessed versus ultrasound and microsphere flow in the phantom and animal models, respectively, using regression analysis. Results Single-volume quantitative CT flow measurements in the phantom (Q CT _ PHANTOM ) were related to reference ultrasound flow measurements (Q US ) by Q CT _ PHANTOM = 1.04 Q US - 0.1 (Pearson's r = 0.98 ; RMSE = 0.09 mL / min / g ). In the animal model (Q CT _ ANIMAL ), they were related to reference microsphere flow measurements (Q MICRO ) by Q CT _ ANIMAL = 1.00 Q MICRO - 0.05 (Pearson's r = 0.96 ; RMSE = 0.48 mL / min / g ). The effective dose per CT measurement was 1.21 mSv. Conclusions The single-volume quantitative CT flow technique only requires bolus tracking data, spatially uniform pre-contrast myocardial attenuation, and a single volume scan acquired near the peak aortic enhancement for accurate, low-dose, myocardial flow measurement (in mL/min/g) under rest and adenosine stress conditions.
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Affiliation(s)
- Logan Hubbard
- University of California, Irvine, Department of Radiological Sciences, Irvine, California, United States
| | - Sabee Molloi
- University of California, Irvine, Department of Radiological Sciences, Irvine, California, United States
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Vats N, Mayer P, Kortes F, Klauß M, Grenacher L, Stiller W, Kauczor HU, Skornitzke S. Evaluation and timing optimization of CT perfusion first pass analysis in comparison to maximum slope model in pancreatic adenocarcinoma. Sci Rep 2023; 13:10595. [PMID: 37391443 PMCID: PMC10313720 DOI: 10.1038/s41598-023-37381-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 06/21/2023] [Indexed: 07/02/2023] Open
Abstract
For implementation, performance evaluation and timing optimization of CT perfusion first pass analysis (FPA) by correlation with maximum slope model (MSM) in pancreatic adenocarcinoma, dynamic CT perfusion acquisitions of 34 time-points were performed in 16 pancreatic adenocarcinoma patients. Regions of interest were marked in both parenchyma and carcinoma. FPA, a low radiation exposure CT perfusion technique, was implemented. Blood flow (BF) perfusion maps were calculated using FPA and MSM. Pearson's correlation between FPA and MSM was calculated at each evaluated time-point to determine optimum timing for FPA. Differences in BF between parenchyma and carcinoma were calculated. Average BF for MSM was 106.8 ± 41.5 ml/100 ml/min in parenchyma and 42.0 ± 24.8 ml/100 ml/min in carcinoma, respectively. For FPA, values ranged from 85.6 ± 37.5 ml/100 ml/min to 117.7 ± 44.5 ml/100 ml/min in parenchyma and from 27.3 ± 18.8 ml/100 ml/min to 39.5 ± 26.6 ml/100 ml/min in carcinoma, depending on acquisition timing. A significant difference (p value < 0.0001) between carcinoma and parenchyma was observed at all acquisition times based on FPA measurements. FPA shows high correlation with MSM (r > 0.90) and 94% reduction in the radiation dose compared to MSM. CT perfusion FPA, where the first scan is obtained after the arterial input function exceeds a threshold of 120 HU, followed by a second scan after 15.5-20.0 s, could be used as a potential imaging biomarker with low radiation exposure for diagnosing and evaluating pancreatic carcinoma in clinical practice, showing high correlation with MSM and the ability to differentiate between parenchyma and carcinoma.
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Affiliation(s)
- Neha Vats
- Clinic for Diagnostic and Interventional Radiology (DIR), Heidelberg University Hospital, Im Neuenheimer Feld 130.3, 69120, Heidelberg, Germany
| | - Philipp Mayer
- Clinic for Diagnostic and Interventional Radiology (DIR), Heidelberg University Hospital, Im Neuenheimer Feld 130.3, 69120, Heidelberg, Germany
| | - Franziska Kortes
- Clinic for Diagnostic and Interventional Radiology (DIR), Heidelberg University Hospital, Im Neuenheimer Feld 130.3, 69120, Heidelberg, Germany
- Radiology Rhein-Neckar, Bodelschwinghstraße 10, 68723, Schwetzingen, Germany
| | - Miriam Klauß
- Clinic for Diagnostic and Interventional Radiology (DIR), Heidelberg University Hospital, Im Neuenheimer Feld 130.3, 69120, Heidelberg, Germany
| | - Lars Grenacher
- Clinic for Diagnostic and Interventional Radiology (DIR), Heidelberg University Hospital, Im Neuenheimer Feld 130.3, 69120, Heidelberg, Germany
- Conradia Radiology and Medical Prevention, Conradia Radiologie München, Augustenstraße 115, 80798, Munich, Germany
| | - Wolfram Stiller
- Clinic for Diagnostic and Interventional Radiology (DIR), Heidelberg University Hospital, Im Neuenheimer Feld 130.3, 69120, Heidelberg, Germany
| | - Hans-Ulrich Kauczor
- Clinic for Diagnostic and Interventional Radiology (DIR), Heidelberg University Hospital, Im Neuenheimer Feld 130.3, 69120, Heidelberg, Germany
| | - Stephan Skornitzke
- Clinic for Diagnostic and Interventional Radiology (DIR), Heidelberg University Hospital, Im Neuenheimer Feld 130.3, 69120, Heidelberg, Germany.
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Dynamic CT myocardial perfusion without image registration. Sci Rep 2022; 12:12608. [PMID: 35871187 PMCID: PMC9308794 DOI: 10.1038/s41598-022-16573-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Accepted: 07/12/2022] [Indexed: 11/26/2022] Open
Abstract
The aim of this study was to validate a motion-immune (MI) solution to dynamic CT myocardial perfusion measurement, in the presence of motion without image registration. The MI perfusion technique was retrospectively validated in six swine (37.3 ± 7.5 kg) with a motion-susceptible (MS) perfusion technique performed for comparison. In each swine, varying severities of stenoses were generated in the left anterior descending (LAD) coronary artery using a balloon under intracoronary adenosine stress, followed by contrast-enhanced imaging with 20 consecutive volume scans per stenosis. Two volume scans were then systematically selected from each acquisition for both MI and MS perfusion measurement, where the resulting LAD and left circumflex (LCx) measurements were compared to reference microsphere perfusion measurements using regression and diagnostic performance analysis. The MI (PMI) and microsphere (PMICRO) perfusion measurements were related through regression by PMI = 0.98 PMICRO + 0.03 (r = 0.97), while the MS (PMS) and microsphere (PMICRO) perfusion measurements were related by PMS = 0.62 PMICRO + 0.15 (r = 0.89). The accuracy of the MI and MS techniques in detecting functionally significant stenosis was 93% and 84%, respectively. The motion-immune (MI) perfusion technique provides accurate myocardial perfusion measurement in the presence of motion without image registration.
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Metabolic flux between organs measured by arteriovenous metabolite gradients. EXPERIMENTAL & MOLECULAR MEDICINE 2022; 54:1354-1366. [PMID: 36075951 PMCID: PMC9534916 DOI: 10.1038/s12276-022-00803-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 02/15/2022] [Accepted: 03/04/2022] [Indexed: 12/15/2022]
Abstract
Mammalian organs convert dietary nutrients into circulating metabolites and share them to maintain whole-body metabolic homeostasis. While the concentrations of circulating metabolites have been frequently measured in a variety of pathophysiological conditions, the exchange flux of circulating metabolites between organs is not easily measurable due to technical difficulties. Isotope tracing is useful for measuring such fluxes for a metabolite of interest, but the shuffling of isotopic atoms between metabolites requires mathematical modeling. Arteriovenous metabolite gradient measurements can complement isotope tracing to infer organ-specific net fluxes of many metabolites simultaneously. Here, we review the historical development of arteriovenous measurements and discuss their advantages and limitations with key example studies that have revealed metabolite exchange flux between organs in diverse pathophysiological contexts.
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Zeng D, Zeng C, Zeng Z, Li S, Deng Z, Chen S, Bian Z, Ma J. Basis and current state of computed tomography perfusion imaging: a review. Phys Med Biol 2022; 67. [PMID: 35926503 DOI: 10.1088/1361-6560/ac8717] [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: 11/17/2021] [Accepted: 08/04/2022] [Indexed: 12/30/2022]
Abstract
Computed tomography perfusion (CTP) is a functional imaging that allows for providing capillary-level hemodynamics information of the desired tissue in clinics. In this paper, we aim to offer insight into CTP imaging which covers the basics and current state of CTP imaging, then summarize the technical applications in the CTP imaging as well as the future technological potential. At first, we focus on the fundamentals of CTP imaging including systematically summarized CTP image acquisition and hemodynamic parameter map estimation techniques. A short assessment is presented to outline the clinical applications with CTP imaging, and then a review of radiation dose effect of the CTP imaging on the different applications is presented. We present a categorized methodology review on known and potential solvable challenges of radiation dose reduction in CTP imaging. To evaluate the quality of CTP images, we list various standardized performance metrics. Moreover, we present a review on the determination of infarct and penumbra. Finally, we reveal the popularity and future trend of CTP imaging.
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Affiliation(s)
- Dong Zeng
- School of Biomedical Engineering, Southern Medical University, Guangdong 510515, China; and Guangzhou Key Laboratory of Medical Radiation Imaging and Detection Technology, Southern Medical University, Guangdong 510515, People's Republic of China
| | - Cuidie Zeng
- School of Biomedical Engineering, Southern Medical University, Guangdong 510515, China; and Guangzhou Key Laboratory of Medical Radiation Imaging and Detection Technology, Southern Medical University, Guangdong 510515, People's Republic of China
| | - Zhixiong Zeng
- School of Biomedical Engineering, Southern Medical University, Guangdong 510515, China; and Guangzhou Key Laboratory of Medical Radiation Imaging and Detection Technology, Southern Medical University, Guangdong 510515, People's Republic of China
| | - Sui Li
- School of Biomedical Engineering, Southern Medical University, Guangdong 510515, China; and Guangzhou Key Laboratory of Medical Radiation Imaging and Detection Technology, Southern Medical University, Guangdong 510515, People's Republic of China
| | - Zhen Deng
- Department of Neurology, Nanfang Hospital, Southern Medical University, Guangdong 510515, People's Republic of China
| | - Sijin Chen
- Department of Medical Imaging Center, Nanfang Hospital, Southern Medical University, Guangdong 510515, People's Republic of China
| | - Zhaoying Bian
- School of Biomedical Engineering, Southern Medical University, Guangdong 510515, China; and Guangzhou Key Laboratory of Medical Radiation Imaging and Detection Technology, Southern Medical University, Guangdong 510515, People's Republic of China
| | - Jianhua Ma
- School of Biomedical Engineering, Southern Medical University, Guangdong 510515, China; and Guangzhou Key Laboratory of Medical Radiation Imaging and Detection Technology, Southern Medical University, Guangdong 510515, People's Republic of China
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Abbona P, Zhao Y, Hubbard L, Malkasian S, Flynn B, Molloi S. Absolute cerebral blood flow: Assessment with a novel low-radiation-dose dynamic CT perfusion technique in a swine model. J Neuroradiol 2021; 49:173-179. [PMID: 34634295 DOI: 10.1016/j.neurad.2021.09.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2021] [Accepted: 09/23/2021] [Indexed: 11/19/2022]
Abstract
RATIONALE AND OBJECTIVES To validate the accuracy of a novel low-dose dynamic CT perfusion technique in a swine model using fluorescent microsphere measurement as the reference standard. MATERIALS AND METHODS Contrast-enhanced dynamic CT perfusion was performed in five swine at baseline and following brain embolization. Reference microspheres and intravenous contrast (370 mg/ml iodine, 1 ml/kg) were injected (5 ml/s), followed by dynamic CT perfusion. Scan parameters were 320×0.5 mm, 100 kVp and 200 mA. On average, 47 contrast-enhanced volume scans were acquired per acquisition to capture the time attenuation curve. For each acquisition, only two systematically selected volume scans were used to quantify brain perfusion with first-pass analysis technique. The first volume scan was selected at the base, simulating bolus tracking, while the second volume at the peak of the time attenuation curve similar to a CT angiogram. Regional low-dose CT perfusion measurements were compared to the microsphere perfusion measurements with t-test, linear regression and Bland-Altman analysis. The radiation dose of the two-volume CT perfusion technique was determined. RESULTS Low-dose CT perfusion measurements (PCT) showed excellent correlation with reference microsphere perfusion measurements (PMICRO) by PCT = 1.15 PMICRO - 0.01 (r = 0.93, p ≤ 0.01). The CT dose index and dose-length product for the two-volume CT perfusion technique were 25.6 mGy and 409.6 mGy, respectively. CONCLUSIONS The accuracy and repeatability of a low-dose dynamic CT perfusion technique was validated in a swine model. This technique has the potential for accurate diagnosis and follow up of stroke and vasospasm.
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Affiliation(s)
- Pablo Abbona
- Department of Radiological Sciences(a), University of California, Irvine, Irvine, CA, 92697, United States of America
| | - Yixiao Zhao
- Department of Radiological Sciences(a), University of California, Irvine, Irvine, CA, 92697, United States of America
| | - Logan Hubbard
- Department of Radiological Sciences(a), University of California, Irvine, Irvine, CA, 92697, United States of America
| | - Shant Malkasian
- Department of Radiological Sciences(a), University of California, Irvine, Irvine, CA, 92697, United States of America
| | - Brooklynn Flynn
- Department of Radiological Sciences(a), University of California, Irvine, Irvine, CA, 92697, United States of America
| | - Sabee Molloi
- Department of Radiological Sciences(a), University of California, Irvine, Irvine, CA, 92697, United States of America.
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Bos D, König B, Blex S, Zensen S, Opitz M, Maier S, Forsting M, Zylka W, Kühl H, Wetter A, Guberina N. Experimental examination of radiation doses from cardiac and liver CT perfusion in a phantom study as a function of organ, age and sex. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2021; 41:512-525. [PMID: 34406127 DOI: 10.1088/1361-6498/abf71f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Accepted: 04/12/2021] [Indexed: 06/13/2023]
Abstract
Cardiac and liver computed tomography (CT) perfusion has not been routinely implemented in the clinic and requires high radiation doses. The purpose of this study is to examine the radiation exposure and technical settings for cardiac and liver CT perfusion scans at different CT scanners. Two cardiac and three liver CT perfusion protocols were examined with the N1 LUNGMAN phantom at three multi-slice CT scanners: a single-source (I) and second- (II) and third-generation (III) dual-source CT scanners. Radiation doses were reported for the CT dose index (CTDIvol) and dose-length product (DLP) and a standardised DLP (DLP10cm) for cardiac and liver perfusion. The effective dose (ED10cm) for a standardised scan length of 10 cm was estimated using conversion factors based on the International Commission on Radiological Protection (ICRP) 110 phantoms and tissue-weighting factors from ICRP 103. The proposed total lifetime attributable risk of developing cancer was determined as a function of organ, age and sex for adults. Radiation exposure for CTDIvol, DLP/DLP10 cmand ED10 cmduring CT perfusion was distributed as follows: for cardiac perfusion (II) 144 mGy, 1036 mGy·cm/1440 mGy·cm and 39 mSv, and (III) 28 mGy, 295 mGy·cm/279 mGy·cm and 8 mSv; for liver perfusion (I) 225 mGy, 3360 mGy·cm/2249 mGy·cm and 54 mSv, (II) 94 mGy, 1451 mGy·cm/937 mGy·cm and 22 mSv, and (III) 74 mGy, 1096 mGy·cm/739 mGy·cm and 18 mSv. The third-generation dual-source CT scanner applied the lowest doses. Proposed total lifetime attributable risk increased with decreasing age. Even though CT perfusion is a high-dose examination, we observed that new-generation CT scanners could achieve lower doses. There is a strong impact of organ, age and sex on lifetime attributable risk. Further investigations of the feasibility of these perfusion scans are required for clinical implementation.
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Affiliation(s)
- Denise Bos
- Institute of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Hufelandstrasse 55, 45147 Essen, Germany
| | - Britta König
- Faculty of Physical Engineering, Westphalian University, Campus Gelsenkirchen, Neidenburger Str. 43, Gelsenkirchen 45897, Germany
| | - Sebastian Blex
- Institute of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Hufelandstrasse 55, 45147 Essen, Germany
| | - Sebastian Zensen
- Institute of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Hufelandstrasse 55, 45147 Essen, Germany
| | - Marcel Opitz
- Institute of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Hufelandstrasse 55, 45147 Essen, Germany
| | - Sandra Maier
- Institute of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Hufelandstrasse 55, 45147 Essen, Germany
| | - Michael Forsting
- Institute of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Hufelandstrasse 55, 45147 Essen, Germany
| | - Waldemar Zylka
- Faculty of Physical Engineering, Westphalian University, Campus Gelsenkirchen, Neidenburger Str. 43, Gelsenkirchen 45897, Germany
| | - Hilmar Kühl
- Department of Radiology, St Bernhard-Hospital Kamp-Lintfort GmbH, Bürgermeister-Schmelzing-Str. 90, Kamp-Lintfort 47475, Germany
| | - Axel Wetter
- Institute of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Hufelandstrasse 55, 45147 Essen, Germany
- Department of Diagnostic and Interventional Radiology, Neuroradiology, Asklepios Klinikum Harburg, 21075 Hamburg, Germany
| | - Nika Guberina
- Department of Radiotherapy, West German Cancer Center, University Hospital Essen, Hufelandstrasse 55, 45147 Essen, Germany
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Hubbard L, Malkasian S, Zhao Y, Abbona P, Molloi S. Combining perfusion and angiography with a low-dose cardiac CT technique: a preliminary investigation in a swine model. Int J Cardiovasc Imaging 2021; 37:1767-1779. [PMID: 33506345 PMCID: PMC8105235 DOI: 10.1007/s10554-020-02130-x] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2020] [Accepted: 12/04/2020] [Indexed: 12/17/2022]
Abstract
Morphological and physiological assessment of coronary artery disease (CAD) is necessary for proper stratification of CAD risk. The objective was to evaluate a low-dose cardiac CT technique that combines morphological and physiological assessment of CAD. The low-dose technique was evaluated in twelve swine, where three of the twelve had coronary balloon stenosis. The technique consisted of rest perfusion measurement combined with angiography followed by stress perfusion measurement, where the ratio of stress to rest was used to derive coronary flow reserve (CFR). The technique only required two volume scans for perfusion measurement in mL/min/g; hence, four volume scans were acquired in total; two for rest with angiography and two for stress. All rest, stress, and CFR measurements were compared to a previously validated reference technique that employed 20 consecutive volume scans for rest perfusion measurement combined with angiography, and stress perfusion measurement, respectively. The 32 cm diameter volumetric CT dose index (\documentclass[12pt]{minimal}
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\begin{document}$${\text{CTDI}}_{\text{vol}}^{32}$$\end{document}CTDIvol32) and size-specific dose estimate (SSDE) of the low-dose technique were also recorded. All low-dose perfusion measurements (PLOW) in mL/min/g were related to reference perfusion measurements (PREF) through regression by PLOW = 1.04 PREF − 0.08 (r = 0.94, RMSE = 0.32 mL/min/g). The \documentclass[12pt]{minimal}
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\begin{document}$${\text{CTDI}}_{\text{vol}}^{32}$$\end{document}CTDIvol32 and SSDE of the low-dose cardiac CT technique were 8.05 mGy and 12.80 mGy respectively, corresponding to an estimated effective dose and size-specific effective dose of 1.8 and 2.87 mSv, respectively. Combined morphological and physiological assessment of coronary artery disease is feasible using a low-dose cardiac CT technique.
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Affiliation(s)
- Logan Hubbard
- Department of Radiological Sciences, Medical Sciences I, B-140, University of California, Irvine, CA, 92697, USA
| | - Shant Malkasian
- Department of Radiological Sciences, Medical Sciences I, B-140, University of California, Irvine, CA, 92697, USA
| | - Yixiao Zhao
- Department of Radiological Sciences, Medical Sciences I, B-140, University of California, Irvine, CA, 92697, USA
| | - Pablo Abbona
- Department of Radiological Sciences, Medical Sciences I, B-140, University of California, Irvine, CA, 92697, USA
| | - Sabee Molloi
- Department of Radiological Sciences, Medical Sciences I, B-140, University of California, Irvine, CA, 92697, USA.
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