Abstract
Purpose: :
Stripping of Descemets membrane and the corneal epithelium (DSEK) is a newly developed surgical technique for the management of corneal opacity due to endothelial failure, which generates entirely new types of specimens consisting of a cell monolayer and basement membrane. Due to the limited amount of tissue, these specimens are frequently discarded as being of little or no diagnostic value. However, in the context of genetic studies requiring confirmation of proband phenotype, histologic corroboration of the clinical diagnosis is mandatory. This study examined the potential for accurate pathologic diagnosis of DSEK specimens using routine histologic analysis combined with a variety of methods for preparing the specimens for fixation.
Methods: :
Specimens (N=12) from patients undergoing DSEK from 2 surgeons (FWP & WJR) were prepared for processing by one of several means: 1) standard handling consisting of placement of tissue on a piece of semiabsorbent paper which was significantly larger than the specimen, 2) tissue placement on a smaller oriented piece of paper in which the specimen filled one end of the paper or 3) submission on a surgical sponge. Specimens were emedded in paraffin on the paper, sectioned, stained with hematoxylin and eosin and periodic acid–Schiff (PAS) stains then analyzed in a masked manner for pathologic diagnosis.
Results: :
In all (6/6) specimens with the clinical diagnosis of Fuchs endothelial corneal dystrophy (FECD) which were mounted on directly on small sized paper at the time of surgery, multiple guttae which were PAS positive could be identified. Endothelial attenuation was also seen. Some specimens showed partial detachment of the tissue from the paper. In a single clinically diagnosed Fuchs specimen not mounted paper, no guttae were seen. In a single specimen of presumed bullous keratopathy, attenuated epithelium was the only abnormal finding. Some (N=3) specimens mounted on larger paper could not be identified by the embedding technician.
Conclusions: :
This study shows that with proper preparation, DSEK specimens can be used to obtain an accurate pathologic diagnosis. In FECD, findings which are diagnostic of the disease can be identified in all properly prepared cases. Specimens from other conditions such as bullous keratopathy may show findings which are consistent with, but not diagnostic of, the clinically diagnosed condition.
Keywords: cornea: endothelium • pathology: human