维生素A缺乏病伴角膜溃疡或角膜软化

定义

溃疡/软化性角化表明部分或全部角膜基质永久性破坏，导致永久性结构改变。溃疡是典型的圆形到椭圆形的“穿孔”缺陷，就好像一个环钻或软木钻已经应用于眼睛。周围的角膜通常是干燥的，但在其他方面是透明的，并且通常缺乏细菌性溃疡的灰色浸润外观。可能不止一个溃疡。小溃疡几乎总是局限于角膜的周围，尤其是角膜的下部和鼻部。溃疡可能很浅，但通常很深。穿孔被虹膜堵塞，从而保留前房。在更晚期的疾病中，坏死的基质脱落，留下一个大的溃疡或后遗症。与较小的溃疡一样，这通常是周围性的，愈合时表现为致密的白色粘附性白斑。通过治疗，浅表溃疡通常愈合时很少留下疤痕；较深的溃疡，尤其是穿孔，形成密集的周围粘附性白斑。

Ulceration/keratomalacia indicates permanent destruction of part or all of the corneal stroma, resulting in permanent structural alteration. Ulcers are classically round to oval "punched-out" defects, as if a trephine or cork-borer had been applied to the eye. The surrounding cornea is generally xerotic but otherwise clear, and typically lacks the grey, infiltrated appearance of ulcers of bacterial origin. There may be more than one ulcer. Small ulcers are almost invariably confined to the periphery of the cornea, especially its inferior and nasal aspects. The ulceration may be shallow, but is commonly deep. Perforations become plugged with iris, thereby preserving the anterior chamber. In more advanced disease the necrotic stroma sloughs, leaving a large ulcer or descemetocele. As with smaller ulcers, this is usually peripheral and heals as a dense, white, adherent leukoma. With therapy, superficial ulcers often heal with surprisingly little scarring; deeper ulcers, especially perforations, form dense peripheral adherent leukomas.

索引词 可用于检索该条目的同义词与别名

• 维生素A缺乏病伴角膜溃疡或角膜软化
• 维生素A缺乏病伴角膜溃疡和干燥症
• 维生素A缺乏伴角膜软化症