Optisol vs Dexsol as storage media for preservation of human corneal epithelium

To compare the efficacy of two storage media, Optisol GS and Dexsol, in preservation of donor corneal epithelium.

A total of 12 pairs of corneas not suitable for transplantation, all with intact epithelium, were used in this study, with one cornea of the pair stored in Optisol GS and its other counterpart in Dexsol. At each of three durations of storage--1, 2, and 4 days--four of these paired corneas were prepared for light microscopy and scanning and transmission electron microscopy. Another four pairs of control cornea were prepared in the same way and placed in universal fixative.

Evaluation of the corneas was made by two observers masked as to the identity of the storage medium and length of storage. Loss of epithelial cells was evaluated by light microscopy. The attachment of the epithelium to the basement membrane,cellular integrity, intercellular junctions, and intracellular organelles were evaluated and compared by electron microscopy.

The magnitude of epithelial loss correlated with the length of storage time. Control corneas maintained normal epithelium with preservation of all epithelial cell layers. Corneas stored for 1 day had minimal damage of the epithelium. Corneas stored for 2 days had a slight increase in epithelial damage, and corneas stored for up to 4 days showed a marked increase in epithelial damage. There were no significant differences between the two storage media. The basal cell layer was maintained in both the media at all time points, usually in good condition with mild-to-moderate damage in some cases.

Loss of donor epithelium is related mainly to the length of storage and is similar in both Optisol GS and Dexsol. The storage time should be less than 4 days,especially when performing penetrating keratoplasty on patients with ocular surface disorders.