Evaluation of contrast enhancement of HU and effective dose for adrenal MDCT

The purpose is to improve the accuracy of dose reduction and adrenal gland diagnosis by analyzing the HU and evaluating the effective dose of contrast CT scan of the adrenal gland in order to evaluate the accuracy of contrast enhancement of adrenal adenomas. We analyzed the dose information of patient DICOM fle that underwent CT scan of adrenal gland examination. CT scan of the adrenal gland performed pre contrast, portal phase, a 3 minute delay and a 15 minute delay. The HU measurement selects the largest region of adrenal lesion. And, mean, standard deviation, and area of the adrenal lesion were analyzed by ROI. Absolute percentage washout (APW) and relative percentage washout (RPW) calculated and the adrenal adenomas diagnosed by threshold value of the percentage washout rate were above APW 60% and RPW 40%. Effective dose was calculated based on DLP of DICOM dose report for adrenal CT scan. HU analyzed of the adrenal gland by calculating APW and RPW. The APW and RPW were analyzed by 52% and 41.8% at 3 minute delay, 73.5% and 59% at 15 minute delay, respectively. The diagnosis of adrenal adenomas was consistent with APW (73.5%) and RPW (59%) above the threshold at 15 minute delay. The effective dose of adrenal CT scan was 16.08 mSv. Therefore, it is necessary for radiation dose reduction