Room: Exhibit Hall | Forum 1
Purpose: To develop viable procedures for the verification of personalized dosimetry in computed tomography (CT) using Monte Carlo-based simulations.
Methods: Mobile equipment was used for rapid, non-invasive determination of equivalent source models of CT scanners under clinical conditions. Anthropomorphic CT dose phantoms from CIRS were scanned, inside of which real-time CT dose probes were equipped at five representative positions. The accumulated dose at the five positions was simultaneously measured during the scan. ImpactMC, a Monte Carlo-based CT dose software program, was used to simulate the scan. The necessary inputs were obtained from the scan parameters, the equivalent source models and the material-segmented CT images of the phantoms. Post-scan 3D dose distributions in the phantoms were obtained and measured, and dose values calculated at the five positions inside the phantom were compared. Because anthropomorphic adult and pediatric body and head phantoms were used, the corresponding different bow tie filters implemented in the scanners were included in the procedures. Initial results were obtained by means of a GE Optima CT 660 and a Toshiba Aquilion One.
Results: In general, the measured and calculated dose values were within the relative uncertainties that had been estimated at 10%.
Conclusion: Viable, rapid procedures were developed that allow the post CT scan dose to be measured and calculated at five points inside anthropomorphic phantoms. The procedures are applicable to any scanner type under clinical conditions. Results show that the procedures are well suited for verifying the applicability of personalized CT dosimetry based on post-scan Monte Carlo calculations.
Funding Support, Disclosures, and Conflict of Interest: The work is funded by Euramet project 15HLT05 PerfusImaging. Authors state no conflict of interest.
Not Applicable / None Entered.
Not Applicable / None Entered.