Department of Ophthalmology, Nagoya University Graduate School of Medicine, Nagoya, Japan.
Department of Ophthalmology, National Defense Medical College, Saitama, Japan.
Acta Ophthalmol. 2019 Aug;97(5):e742-e746. doi: 10.1111/aos.14038. Epub 2019 Jan 30.
Based on the hypothesis that silicone oil (SO) with a higher refractive index than water induces unexpected vignetting effects during surgeries, we aimed to investigate the relationship between the volume of SO and light intensity using a surgical microscope.
Using a light-sensitive paper and model eye filled with varying volumes (0%, 50%, 62.5%, 75%, 87.5% and 100%) of SO, the light intensity of intraocular lens (IOL) with various refractive powers (0, 10 and 20 dioptres) illuminated by a surgical microscope was measured.
Light exposure density with 1.0% coaxial and oblique light was approximately 22-fold higher than that with 0.1% coaxial and oblique light. Further, it was approximately 34-fold higher in eyes with +20 D IOL than in those with no IOL. The density in eyes with 75% SO was the highest among all groups followed by that with 0% SO. Light exposure densities in the eyes with 75% and 0% SO were significantly higher than those with other volumes of SO. In SO-filled eyes, a microscope set with only an oblique light and a filter successfully reduced light exposure.
Silicone oil-related vision loss (SORVL) during SO removal surgeries might be due to increased light exposure on the macular retina caused by the SO-associated vignetting effect. SORVL could be prevented by placing a filter in the microscope during SO removal surgeries.
基于硅油（SO）的折光率高于水会在手术中产生意想不到的暗角效应的假设，我们旨在使用手术显微镜研究 SO 体积与光强度之间的关系。
使用感光纸和充满不同体积（0%、50%、62.5%、75%、87.5%和 100%）SO 的模型眼，测量不同屈光力（0、10 和 20 屈光度）的人工晶状体（IOL）在手术显微镜下的光强度。
1.0%同轴和斜光的光暴露密度比 0.1%同轴和斜光高约 22 倍。此外，+20 D IOL 眼的光暴露密度比无 IOL 眼高约 34 倍。在所有组中，75%SO 眼的密度最高，其次是 0%SO 眼。75%和 0%SO 眼的光暴露密度明显高于其他 SO 体积的眼。在充满 SO 的眼中，仅使用斜光和滤光片的显微镜设置成功降低了光暴露。
在 SO 取出手术中，与 SO 相关的视力丧失（SORVL）可能是由于 SO 引起的暗角效应导致黄斑视网膜的光暴露增加所致。在 SO 取出手术中，通过在显微镜中放置滤光片可以预防 SORVL。
