Abstract：
INTRODUCTION:This study aimed to investigate the feasibility of generating pseudo dual-energy CT (DECT) from one 120-kVp CT by using convolutional neural network (CNN) to derive additional information for quantitative image analysis through phantom study. METHODS:Dual-energy scans (80/140 kVp) and single-energy scans (120 kVp) were performed for five calibration phantoms and two evaluation phantoms on a dual-source DECT scanner. The calibration phantoms were used to generate training dataset for CNN optimization, while the evaluation phantoms were used to generate testing dataset. A CNN model which takes 120-kVp images as input and creates 80/140-kVp images as output was built, trained, and tested by using Caffe CNN platform. An in-house software to quantify contrast enhancement and synthesize virtual monochromatic CT (VMCT) for CNN-generated pseudo DECT was implemented and evaluated. RESULTS:The CT numbers in 80-kVp pseudo images generated by CNN are differed from the truth by 11.57, 16.67, 13.92, 12.23, 10.69 HU for syringes filled with iodine concentration of 2.19, 4.38, 8.75, 17.5, 35 mg/ml, respectively. The corresponding results for 140-kVp CT are 3.09, 9.10, 7.08, 9.81, 7.59 HU. The estimates of iodine concentration calculated based on the proposed method are differed from the truth by 0.104, 0.603, 0.478, 0.698, 0.795 mg/ml for syringes filled with iodine concentration of 2.19, 4.38, 8.75, 17.5, 35 mg/ml, respectively. With regards to image quality enhancement, VMCT synthesized by using pseudo DECT shows the best contrast-to-noise ratio at 40 keV. CONCLUSION:In conclusion, the proposed method should be a practicable strategy for iodine quantification in contrast enhanced 120-kVp CT without using specific scanner or scanning procedure.
journal_name
J Appl Clin Med Physjournal_title
Journal of applied clinical medical physicsauthors
Huang WH,Jhan KJ,Yang CCdoi
10.1002/acm2.13148subject
Has Abstractpub_date
2020-10-14 00:00:00issn
1526-9914pub_type
杂志文章abstract：PURPOSE:To quantify the effects of combining layer-based repainting and respiratory gating as a strategy to mitigate the dosimetric degradation caused by the interplay effect between a moving target and dynamic spot-scanning proton delivery. METHODS:An analytic routine modeled three-dimensional dose distributions of p...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
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更新日期：2019-09-01 00:00:00
abstract：:For most computed tomography (CT) simulators, radiation therapists must remove the flat couch top to perform daily CT quality assurance (QA), and then use separate tools to perform localization-laser QA. This process wastes time and effort and creates the opportunity for accidents to occur. In this study, we tested a ...
journal_title：Journal of applied clinical medical physics
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journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
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更新日期：2012-01-05 00:00:00
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journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
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更新日期：2009-06-02 00:00:00
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journal_title：Journal of applied clinical medical physics
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journal_title：Journal of applied clinical medical physics
pub_type： 临床试验,杂志文章
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更新日期：2004-04-01 00:00:00
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journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
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journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
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journal_title：Journal of applied clinical medical physics
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pub_type： 临床试验,杂志文章
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更新日期：2001-04-01 00:00:00
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更新日期：2020-07-01 00:00:00
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更新日期：2017-09-01 00:00:00
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更新日期：2012-03-08 00:00:00
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更新日期：2013-09-06 00:00:00
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doi：10.1120/jacmp.v10i4.2911
更新日期：2009-10-15 00:00:00
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journal_title：Journal of applied clinical medical physics
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doi：
更新日期：2011-01-30 00:00:00
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更新日期：2015-11-08 00:00:00
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journal_title：Journal of applied clinical medical physics
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journal_title：Journal of applied clinical medical physics
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journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
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