Peled Alon, Moshe Shlomo, Chodick Gabriel
Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
Occupational Health, Jerusalem and Shfela District, Maccabi Healthcare Services.
Harefuah. 2018 Oct;157(10):650-654.
The lens of the eye is among the most sensitive organs to ionizing radiation in the human body. The cataract is the earliest documented side effect of ionizing radiation, first reported in lab animals in 1897, only a year after the discovery of X-rays, and in 1906 among human radiation technicians. However, the exact mechanisms underlining this pathology have yet to be uncovered. In particular, the question as to whether radiation-induced cataract is a deterministic event, meaning a threshold dose must be exceeded in order for it to develop, still remains. Recent epidemiological studies, performed on populations exposed to lower radiation doses than those previously perceived cataractogenic, have led the International Commission on Radiological Protection (ICRP) in April 2011 to reduce its eye dose threshold for cataract induction from 2 Gy to 0.5 Gy, and the occupational annual dose limit from 150 mSv to 20 mSv/year. However, the ICRP have yet to support a stochastic effect (linear non-threshold) for radiation- induced cataract, although suggested by several studies. In this article, we review the current knowledge on radiation-induced cataract, including the speculated mechanism for its development, evidence for genetically predisposed populations, and the main recent epidemiological studies.
眼睛晶状体是人体中对电离辐射最为敏感的器官之一。白内障是最早有文献记载的电离辐射副作用，1897年在实验动物中首次报道，距离X射线发现仅一年，1906年在人类放射技术人员中也有发现。然而，这种病理现象背后的确切机制尚未被揭示。特别是，辐射诱发白内障是否是一种确定性事件，即必须超过阈值剂量才会发生，这个问题仍然存在。最近针对接触辐射剂量低于以往认为致白内障剂量人群开展的流行病学研究，促使国际放射防护委员会（ICRP）在2011年4月将诱发白内障的眼部剂量阈值从2 Gy降至0.5 Gy，并将职业年剂量限值从150 mSv降至20 mSv/年。然而，尽管有多项研究提出相关建议，但ICRP尚未支持辐射诱发白内障存在随机效应（线性无阈值）这一观点。在本文中，我们综述了目前关于辐射诱发白内障的知识，包括其发展的推测机制、遗传易感性人群的证据以及近期主要的流行病学研究。
