Ultraviolet dosimetry on the local crystalline lens utilizing a mannequin model

为了阐明白内障的发生与紫外线照射之间的关系，我们进行了以下研究：1）在气候不同的三个地方（北海道、石川和冲绳）调查了白内障的患病率和皮质混浊的定位。我们发现白内障患病率和混浊类型的差异。2)用人体模型UV剂量计和接触透镜型剂量计进行眼睛上UV暴露的剂量测定。紫外线照射对眼睛的影响小于额头的一半。最高的暴露被发现在下鼻侧。3)在活体兔眼上研究了紫外线吸收接触透镜的效果。接受紫外线照射而无接触透镜保护的眼睛有角膜上皮和内皮损伤、角膜水肿和白内障的证据。相比之下，带接触透镜的保护没有显示出这些变化。（4）为了明确瞳孔缩小和眼睑对强光照射的反应，减少眼睛的紫外线照射，我们制作了一个装置，使我们能够测量在日常生活照明条件下眼睑和瞳孔的变化。健康志愿者和白内障志愿者（老年白内障患者除外）在室内条件下的瞳孔大小约为3mm，在室外条件下约为2mm。眼睑和瞳孔大小的变化首先是瞳孔的变化，其次是上眼睑的下降和下眼睑的升高。从流行病学和基础研究来看，紫外线暴露与白内障的发生有关。

To clarify the relation between cataract development and ultraviolet exposure, we investigated following studies ; 1)Cataract prevalence and localization of cortical opacity were investigated among climatically different three places (Hokkaido, Ishikawa, and Okinawa). We find the difference of cataract prevalence and type of opacity. 2)Dosimetry of UV exposure on the eye was performed with a mannequin model UV dosimeter and contact lens type dosimeter were produced. UV exposure on the eye was less than a half of forehead. The highest exposure was found in the lower nasal side. 3)The effect of UV absorbing contact lens was studied on a living rabbit eyes. The eyes that had received UV radiation without contact lens protection had evidence of both corneal epithelium and endothelium injury, corneal edema, and cataract. In contrast, with contact lens protection did not show these changes. 4)To clarify the effects of miosis and squinting eye lids against bright light reducing UV exposure in the eye, a equipment which enable us to measure the changes of eye lids and pupillary size under the condition of daily life illumination was made. The pupillary size of healthy and cataractous volunteer (except elder cataractous patients) were around 3 mm in the indoors condition, and 2 mm in outdoors. The first changes of eye lids and pupillary size was seen pupillary changes, followed by dropping of upper eye lid and elevation of lower eye lid. It was no doubt that UV exposure related to cataract development from epidemiological and basic studies.