Development of a computational adult brain model and applications to radiation dosimetry of brain structures during CT examinations

Date(s) - 11/18/2014
10:30 am

Nelia Sanchez Long, PhD Candidate

Current methods for dose calculations in the brain following CT examinations often involve rough estimations using CTDI measurements and average brain measurements calculated in simplified experiments. Although these methods may be sufficient to estimate risks using the current stochastic risk models they may not be adequate for future epidemiology studies that require absorbed radiation doses for a specific structure in order to identify modest risk effects and organ specificity. The goal of this project is to create a dosimetric tool that will provide the user with suborgan radiation doses in the brain for available CT head/brian protocols. These doses will be incorporated in the development of radiation risk models for glioma and meningioma incidence and its potential link to previous CT examinations. To this end, a computational model of the adult brain for use with the University of Florida reference male and female hybrid adult reference phantoms was created. These models were then used to develop a slice-specific dose library for a variety of CT exams of the head and brain which was then use to develop a dosimetry software tool for use in epidemiology. This software provides doses for different sub-organs in the brain. Furthermore, this research studied the variations in thyroid dose during CT examinations. These variations depend on thyroid size and its anatomical location.