Abstract：Objective To compare the difference between volume CT dose index (CTDIvol) and size-specific dose estimate (SSDE)
based on water equivalent diameter (WED) (that is SSDEWED) in measuring radiation dose on head CT in children and to explore
a fast method for calculating SSDEWED. Methods The CT imaging data of 1136 children from January to December 2021 were
analyzed retrospectively, they were divided into 4 groups including A, B, C, D group according to their ages. The differences between
CTDIvol and SSDEWED in 4 groups were compared. The correlation between SSDEWED and tube current, WED, and also the correlation
between WED, conversion factor (f) and age were analyzed. Results The mean CTDIvol was (9.52±1.32) mGy and the mean
SSDEWED was (8.30±0.67) mGy in 1136 cases, and the difference was statistically significant (P<0.001). The CTDIvol was smaller
than SSDEWED in group A, the CTDIvol was larger than SSDEWED in the other groups, and the coefficient of variation, full range, and
inter quartile range of CTDIvol were larger than those of SSDEWED in all groups. There was a strong positive correlation between
SSDEWED and tube current (100 kVp: r=0.95, P<0.001; 120 kVp: r=0.91, P<0.001) . There was a strong positive correlation between
SSDEWED and WED at 100 kVp (r=0.82, P<0.001), the correlation was moderate at 120 kVp (r=0.61, P<0.001), and f decreased with
age. Conclusion SSDEWED allows a more accurate and reliable measurement of radiation dose on head CT examination in children,
allows a more rapid calculation of SSDEWED by establishing a regression model between f and age.
张见，刘鹏，张晓军. 基于管电流自动调制模式的儿童头颅
CT体型特异性剂量的快速估算[J]. 中国医疗设备, 2023, 38(10): 73-78.
ZHANG Jian, LIU Peng, ZHANG Xiaojun. Rapid Estimation of Size-Specific Dose of Head CT in Children Based on
Automatic Tube Current Modulation Mode. China Medical Devices, 2023, 38(10): 73-78.
