Effects of organ dose modulation technique on image quality and radiation dose in sinus CT scanning
10.3760/cma.j.cn112271-20211010-00407
- VernacularTitle:器官剂量调制技术对鼻窦CT图像质量和辐射剂量的影响
- Author:
Dewu YANG
1
;
Yan SUI
;
Kang LIU
;
Yantao NIU
Author Information
1. 北京卫生职业学院医学技术系，北京 102433
- Keywords:
Organ dose modulation;
Sinus;
Eye lens;
Radiation protection;
Image quality
- From:
Chinese Journal of Radiological Medicine and Protection
2022;42(3):230-234
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the effects of organ dose modulation (ODM) on image quality and radiation dose to lens during sinus CT scanning.Methods:The GE Revolution EVO CT was used to scan the anthropomorphic head with ODM turned off as the control group and ODM turned on as the observation group. With different parameter combinations of tube voltage (140, 120, 100 kV), noise index (N17, N18), pitch (0.531, 0.969 at 20 cm collimation width, 0.516, 0.984 at 40 mm collination width), 24 series of images were acquired respectively. The tube current (mA) valuesat the anterior (A), left (L), posterior (P) and right (R) positions, volume CT dose index (CTDI vol) and dose length product (DLP) were recorded. Average CT values (AV), standard deviation (SD), signal-to-noise ratio (SNR), contrast to noise ratio (CNR) and image quality factor (FOM) of ROI were calculated. Double blind method was used to evaluate the edge sharpness, soft tissue level, noise and artifact on a subjective scale of 3 points. Results:For the combinations of different scanning parameters, the radiation dose of the observation group was lower than that of the control group. The tube current attheposition A for the observation group was lower than that of the control group, and the difference was statistically significant ( t=2.28, P<0.05). The differences oftube currentsatposotions of L, P and R, CTDI vol and DLP values in twogroupswere not statistically significant ( P>0.05). There were no significant differences in SD, SNR, CNR and FOM between the two groups of images ( P>0.05). There were no significant differences in the subjective scores of edge sharpness, soft tissue gradation, noise and artifacts between the two groups ( P>0.05). Conclusions:ODM technique can effectively reduce the radiation dose of eye lens without decompromising the image quality, which could meet the requirements of diagnosis, and accord with the principle of radiological protection optimization.
