Phantom Experimental Study on Patient Doses Obtained from 320-Multidetector-Row Computed Tomography in Whole-Brain Perfusion Scan

Abstract

This study aimed to precisely evaluate organ dose and effective dose (E) obtained from a 320-multidetector-row computed tomography (CT) scanner in brain perfusion scans and to estimate the conversion factor (k) between E and dose length product (DLP). A total of 270 thermoluminescent dosemeters were implanted in a male anthropomorphic phantom to measure air kerma. The ratios of mass-energy absorption coefficients were used to convert air kerma into organ doses. The organ doses ranged from 0.01 to 150 mGy. Doses in brain, salivary glands and red bone marrow were relatively high, and dose in eye lens reached about 110 mGy. The resulting effective dose was 5.30 mSv. The resulting conversion factor k = (0.0022 ± 0.0002) mSv·(mGy·cm)−1 was not significantly different from that of 0.0021 mSv·(mGy·cm)−1 reported for head CT scan in ICRP Publication 102.