Abstract：
PURPOSE:The purpose of this study was to assess the accuracy of a Monte Carlo simulation-based method for estimating radiation dose from multidetector computed tomography (MDCT) by comparing simulated doses in ten patients to in-vivo dose measurements. METHODS:MD Anderson Cancer Center Institutional Review Board approved the acquisition of in-vivo rectal dose measurements in a pilot study of ten patients undergoing virtual colonoscopy. The dose measurements were obtained by affixing TLD capsules to the inner lumen of rectal catheters. Voxelized patient models were generated from the MDCT images of the ten patients, and the dose to the TLD for all exposures was estimated using Monte Carlo based simulations. The Monte Carlo simulation results were compared to the in-vivo dose measurements to determine accuracy. RESULTS:The calculated mean percent difference between TLD measurements and Monte Carlo simulations was -4.9% with standard deviation of 8.7% and a range of -22.7% to 5.7%. CONCLUSIONS:The results of this study demonstrate very good agreement between simulated and measured doses in-vivo. Taken together with previous validation efforts, this work demonstrates that the Monte Carlo simulation methods can provide accurate estimates of radiation dose in patients undergoing CT examinations.
journal_name
Med Physjournal_title
Medical physicsauthors
Bostani M,Mueller JW,McMillan K,Cody DD,Cagnon CH,DeMarco JJ,McNitt-Gray MFdoi
10.1118/1.4906178subject
Has Abstractpub_date
2015-02-01 00:00:00pages
1080-6issue
2eissn
0094-2405issn
2473-4209journal_volume
42pub_type
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