Fernandes Bruno F, Logan Patrick, Zajdenweber Moyses E, Santos Leonardo N, Cheema Devinder P, Burnier Miguel N
Department of Ophthalmology and Pathology, The McGill University Health Center and Henry C. Witelson Ocular Pathology Laboratory, Montreal, Quebec, Canada.
Pathology. 2008 Oct;40(6):623-6. doi: 10.1080/00313020802320648.
Keratoconus is a bilateral and asymmetrical corneal ectasia. The pathophysiology of this disorder has yet to be fully elucidated. The purpose of our study was to document the prevalence of the most common morphological features of keratoconic corneas.
A retrospective analysis of 49 cases diagnosed as keratoconus between 2001 and 2006 was undertaken. Histopathological reports were reviewed to obtain data such as age and gender. Specimens were fixed in 10% buffered paraformaldehyde solution for 24 h, bisected through the centre of the button, and embedded in paraffin. Sections were stained with haematoxylin and eosin (H&E) and periodic acid-Schiff (PAS) for light microscopic examination.
The studied group was composed of 29 men and 20 women. Age at the time of the penetrating keratoplasty was 39 +/- 14 years (mean +/- standard deviation). Forty of the 49 specimens (82%) presented with epithelial thinning. Other common features of keratoconus included breaks in Bowman's layer in 35 (71%), compaction of the stromal collagen fibres in 31 (63%), and folds in Descemet's membrane in 31 (63%) cases. Other less common histopathological findings were: presence of superficial iron deposits in 14 (29%), deep stromal scarring in 12 (24%), epithelial scarring in 11 (22%), endothelial cell loss in 11 (22%), and breaks in Descemet's membrane in nine (18%) cases.
Some of the histopathological findings associated with keratoconus are subtle. It is important to be aware of them in order to properly confirm the clinical diagnosis.
圆锥角膜是一种双侧不对称的角膜扩张症。该疾病的病理生理学尚未完全阐明。我们研究的目的是记录圆锥角膜最常见形态特征的发生率。
对2001年至2006年间诊断为圆锥角膜的49例病例进行回顾性分析。查阅组织病理学报告以获取年龄和性别等数据。标本用10%缓冲多聚甲醛溶液固定24小时，通过纽扣中心将其切成两半，并嵌入石蜡中。切片用苏木精和伊红（H&E）以及过碘酸希夫（PAS）染色，用于光学显微镜检查。
研究组由29名男性和20名女性组成。穿透性角膜移植时的年龄为39±14岁（平均值±标准差）。49个标本中有40个（82%）出现上皮变薄。圆锥角膜的其他常见特征包括35个（71%）病例的Bowman层破裂、31个（63%）病例的基质胶原纤维致密化以及31个（63%）病例的Descemet膜褶皱。其他不太常见的组织病理学发现包括：14个（29%）病例存在浅表铁沉积、12个（24%）病例存在深层基质瘢痕形成、11个（22%）病例存在上皮瘢痕形成、11个（22%）病例存在内皮细胞丢失以及9个（18%）病例的Descemet膜破裂。
一些与圆锥角膜相关的组织病理学发现很细微。为了正确地确诊临床诊断，了解这些发现很重要。
