Abstract：Objective To explore the radiation dose to radiation-sensitive organs combined with unprotected, 180° and 360°
lead protection under different positioning of chest CT scanning. Methods With automatic tube current technology, the radiation
dose of lens, thyroid, mammary gland and gonad during chest CT were measured using anterior-posterior positioning image,
anterior-posterior + lateral positioning image in anthropomorphic phantom respectively. Three kinds of lateral positioning
were adopted, including anterior axillary line, mid-axillary line, and posterior axillary line, combined with unprotected, 180°
and 360° lead protection. Results When using the mid-axillary line positioning, compared with the anteroposterior positioning
images, the radiation dose of mammary gland, lens and gonad organs in anteroposterior + lateral positioning images were
significantly lower (P<0.05), but there was no significant difference in the radiation dose of thyroid. When the positioning image
was anteroposterior and lateral position, compared with the anterior axillary line, the radiation dose of mammary gland, thyroid and
gonad in the mid-axillary line were decreased; compared with the posterior axillary line, the radiation dose of lens was decreased
in the mid-axillary line (P<0.05). With the positioning image was anteroposterior and mid-axillary line position, the radiation dose
of thyroid with 180° lead protection in routine dose scanning was less than that without protection in low dose scanning, and
the difference was statistically significant (P<0.05). The radiation dose of gonads under 360° lead protection in routine dose
scanning was less than 180° lead protection and no protection in low dose scanning, the difference was statistically significant
(P<0.05); there was no significant difference in the radiation dose of gonad in the last two ways. Conclusion Conventional chest CT
scanning generally adopts automatic tube current technology, anteroposterior positioning image and mid-axillary line positioning.
Anteroposterior + lateral positioning images can be used to reduce the radiation dose of mammary gland, lens and gonad.
Mid-axillary line is still recommended for lateral location. Under this condition, there is only 180° lead protection for gonad. It is
recommended to adopt 360° lead protection with better effect, and 180° lead protection can be carried out for thyroid according to
the situation.
王杰，李信友，彭刚，孙静坤. 不同扫描定位及防护方法在胸部CT敏感器官辐射剂量的体模研究[J]. 中国医疗设备, 2022, 37(4): 78-81.
WANG Jie, LI Xinyou, PENG Gang, SUN Jingkun. Study on Radiation Dose to Sensitive Organs of Phantom in Chest CT Scanning with
Different Positioning and Protection Methods. China Medical Devices, 2022, 37(4): 78-81.
