在视网膜手术中清楚地看见眼底是必需的。但在巩膜摺叠手术中手术者的观察常被角膜上皮水肿所阻。角膜上皮水肿最常见的原因是对眼球的操作,引起暂时性眼内压增高。在准备手术时角膜为化学物所损伤以及原先有角膜病的眼多易发生上皮性水肿。手术者常规地冲洗角膜企图保持清楚见到眼底。有时用一片湿的凝胶海绵来保持角膜清亮, It is necessary to clearly see the fundus during retinal surgery. However, the observation of the surgeon in the scleral fold surgery is often blocked by corneal epithelial edema. Corneal epithelial edema is the most common cause of the operation of the eye, causing a temporary increase in intraocular pressure. In preparation for surgery corneal chemical damage and the original corneal eye prone to epithelial edema. Surgeons routinely rinse the cornea in an attempt to keep the fundus clearly visible. Sometimes with a wet gel sponge to keep the cornea clear,