Changes of X-ray examination mode for ophthalmic inpatients and impact on radiation dose level from 2019 to 2020 / 中华放射医学与防护杂志

ABSTRACT

Objective:To analyze and compare the X-ray procedures and radiation dose composition of ophthalmic inpatients, and to explore the changes of the X-ray examination mode in recent years and the effect of optimization in imaging technology on the radiation dose level of the patients.Methods:The simple random sampling method was used to retrospectively select the imaging data of the ophthalmic inpatients in the Second Affiliated Hospital of Zhejiang University School of Medicine from July 1st to November 31st in 2019 and from July 1st to November 31st in 2020. A total of 516 cases were selected according to the imaging time, including 258 cases in 2019 and 258 cases in 2020. Based on our previous research and the related documents of low-dose CT screening, a series of optimizations on CT scanning parameters and process were carried out in 2020, including the frequency of DR and CT scanning, the number of examinations per capita, the composition ratio of CT and DR, and X-ray dose per capita.Results:In 2020, the average effective doses of chest CT and orbital CT for ophthalmic inpatients were (2.587±1.586) mSv and (0.877±0.733) mSv, significantly lower than those in 2019 ( F=0.52, 0.72, P<0.05), and decreased by 34.82% and 37.13%, respectively. There was no significant difference in the average effective dose of chest DR and head CT between 2020 and 2019 ( F=6.01, 1.81, P>0.05). The number of X-ray examination per capita increased by 0.15 times, and the effective dose increased by 1.44 times (1.589 mSv). Chest DR was the main type of X-ray examination, accounting for 68.79% of all examinations in 2019, while chest CT was the main type, accounting for 71.05% in 2020. The composition of chest CT in 2020 increased by 63.17% compared with 2019, and the compositions of chest DR, orbital CT and cranial CT were decreased by 53.88%, 5.79% and 2.89%, respectively. Conclusions:With dose optimization measures, the single CT dose of ophthalmic inpatients in 2020 was lower than that in 2019. Chest CT increased significantly in frequency, and became main X-ray examination instead of chest DR which made the effective dose of ophthalmic inpatients increasing significantly.