Abstract: This work aims to study the CT scan radiation dose of the human anatomical region of hospital scale and diagnostic dose level of adult CT examination. A total of 15,440 CT scan data were collected from the anatomical regions of all adults who underwent diagnostic CT examinations on GE Light Speed 16 CT equipment from February 2018 to January 2019. The volumetric dose index (CTDI_vol) and the dose length product (DLP) of the patient’s anatomical region were counted according to the anatomical region classification. The quantities of CTDI_vol and DLP in the scan data were statistically analyzed using spss19 software and the effective dose (ED) was calculated. As a result, the DRL values of CTDI_vol in each anatomical region were as follows: 87.75 mGy for the brain, 8.09 mGy for the lungs, 15.82 mGy for the upper and lower abdomen, and 15.79 mGy for the upper and lower abdominal pelvis. The DRL values of DLP in each anatomical region were as follows: for the brain was 1 053.03 mGy cm, for the lung was 245.19 mGy cm, for the upper and lower abdomen was 269.96 mGy cm, for the upper and lower abdominal pelvic was 835.20 mGy cm. The DRL values of CTDI_vol and DLP in lung anatomical region (8.09 mGy, 245.19 mGy cm) were lower than those in other regions of China and other countries. The DRL values of CTDI_vol and DLP in patients under 60 year old were lower than 8.09 mGy and 245.19 mGy cm, and the DRL values of CTDI_vol and DLP in CT scan of patients over 60 year old were higher than 8.09 mGy and 245.19 mGy cm. Taking all together, according to the analysis of the research results, the CT radiation dose and the adult CT examination dose level of each anatomical area of the hospital can be determined, which provides a basis for optimizing the CT scanning technique and monitoring the radiation dose.

Key words: radiation dose, X-ray computed tomography, dose optimization, diagnostic dose level