Paulis Leonie E, Schnerr Roald S, Halton Jarred, Qin Zhi Zhen, Chua Arlene
Médecins Sans Frontières, International, Amsterdam, The Netherlands.
Department of Digital Health, Stop TB, Geneva, Switzerland.
PLOS Glob Public Health. 2025 Jan 24;5(1):e0003986. doi: 10.1371/journal.pgph.0003986. eCollection 2025.
Ultraportable (UP) X-ray devices are ideal to use in community-based settings, particularly for chest X-ray (CXR) screening of tuberculosis (TB). Unfortunately, there is insufficient guidance on the radiation safety of these devices. This study aims to determine the radiation dose by UP X-ray devices to both the public and radiographers compared to international dose limits. Radiation dose measurements were performed with four UP X-ray devices that met international criteria, utilizing a clinically representative CXR set-up made with a thorax phantom. Scatter and leakage radiation dose were measured at various positions surrounding the phantom and X-ray tube, respectively. These measurements were used to calculate yearly radiation doses for different scenarios based on the median of all UP X-ray devices. From the yearly scatter doses, the minimum distances from the phantom needed to stay below the international public dose limit (1 mSv/year) were calculated. This distance was longest in the direction back towards the X-ray tube and shortest to the left/right sides of the phantom, e.g., 4.5 m and 2.5 m resp. when performing 50 exams/day, at 90 kV, 2.5 mAs and source skin distance (SSD) 1 m. Additional calculations including leakage radiation were conducted at a typical radiographer position (i.e., behind the X-ray tube), with a correction factor for wearing a lead apron. At 2 m behind the X-ray tube, a radiographer wearing a lead apron could perform 106 exams/day at 2.5 mAs and 29 exams/day at 10 mAs (90 kV, SSD 1 m), while keeping his/her radiation dose below the public dose limit (1 mSv/year) and well below the radiographer dose limit (20 mSv/year). In most CXR screening scenarios, the radiation dose of UP X-ray devices can be kept below 1 mSv/year by employing basic radiation safety rules on time, distance and shielding and using appropriate CXR exposure parameters.
超便携式（UP）X射线设备非常适合在社区环境中使用，特别是用于肺结核（TB）的胸部X射线（CXR）筛查。不幸的是，关于这些设备的辐射安全方面的指导不足。本研究旨在确定与国际剂量限值相比，UP X射线设备对公众和放射技师的辐射剂量。使用符合国际标准的四台UP X射线设备进行辐射剂量测量，利用胸部模型构建具有临床代表性的CXR设置。分别在模型和X射线管周围的不同位置测量散射和泄漏辐射剂量。这些测量结果用于根据所有UP X射线设备的中位数计算不同场景下的年度辐射剂量。从年度散射剂量中，计算出为使公众辐射剂量低于国际剂量限值（每年1 mSv）所需与模型保持的最小距离。这个距离在朝向X射线管的方向上最长，在模型的左侧/右侧最短，例如，当每天进行50次检查、管电压90 kV、管电流2.5 mAs且源皮距（SSD）为1 m时，分别为4.5 m和2.5 m。在典型的放射技师位置（即X射线管后方）进行了包括泄漏辐射在内的额外计算，并考虑了佩戴铅围裙的校正因子。在X射线管后方2 m处，佩戴铅围裙的放射技师在管电流2.5 mAs时每天可进行106次检查，在管电流10 mAs时每天可进行29次检查（管电压90 kV，源皮距1 m），同时使其辐射剂量低于公众剂量限值（每年1 mSv）且远低于放射技师剂量限值（每年20 mSv）。在大多数CXR筛查场景中，通过在时间、距离和屏蔽方面采用基本的辐射安全规则并使用适当的CXR曝光参数，UP X射线设备的辐射剂量可保持在每年1 mSv以下。
