Comparison of rabbit and human corneas stored in Optisol-GS: changes in stromal sodium

Abstract

Rabbit corneas responded differently from human corneas to storage in Optisol-GS. The hydration levels increased to a greater level in rabbit than human corneas under both storage conditions. The trends in amounts of both free and total sodium were similar between the species, although the absolute amounts differed. The largest discrepancy was observed in the amount of bound sodium, with the rabbit corneas experiencing large increases not documented in the human tissue. These results suggest that direct comparisons of stromal hydration and ionic environment between the species should be approached with caution.

The Effects of Epithelial Viability on Stromal Keratocyte Apoptosis in Porcine Corneas Stored in Optisol-GS

“…Corneal edema during preservation was even more significant when the epithelium was missing before preservation. Since stromal sodium concentration increased in the absence of corneal epithelium, 11,12 this might contribute to the more significant corneal edema as well as keratocyte apoptosis in group 1.…”

“…Since sodium content increases 11,12 and stromal proteoglycan decreases 13 in the preservation medium when the corneal epithelium is removed before storage, it is possible that various keratocyte populations react differently to the change in stromal sodium and proteoglycan content during preservation. This may thus result in more keratocyte loss in the anterior stroma when corneal epithelium is absent.…”

“…8-10 Jablonski-Stiemke et al 11,12 showed that the presence of an intact epithelium is required for maintaining hydration and sodium levels within the corneal stroma during storage. Removal of the epithelium prior to storage results in loss of stromal proteoglycans 13 as well as increased sodium content and hydration, 11,12 which may affect postkeratoplasty deturgescence. However, the effect of stromal hydration and sodium content change on the stromal keratocyte number has not been studied.…”