Purpose:
Evaluate endothelial vitality in vitro of precut corneas after varying storage time in Optisol
Methods:
Four pairs of corneas were obtained from MidSouth Eye Bank. Visante OCT with pachymetry was performed on each cornea prior to manipulation. All test corneas were mounted on a Moria artificial anterior chamber with BSS infusion and sectioned under sterile conditions using a microkeratome with a 300-µm head to create an anterior lamellar cap. After dissection, the cap was placed over the posterior lamella and the corneas were replaced in Optisol and refrigerated for 1, 3, 5, or 7 days --mimicking normal eyebank protocol. No manipulation was performed on the control corneas. On the final day of storage, the test and control corneas were imaged with Visante OCT for post storage pachymetry. It was noted whether the anterior lamellar cap was still in place on the test cornea after storage. Each cornea underwent vital staining using Trypan Blue and Alizarin Red. After vital staining, photomicrographs were taken of three random areas of the endothelial cell layer at 4x and 10x objective strength. Vital stained cell counts were derived from the high magnification images. Results were then analyzed for statistical significance using a paired t test.
Results:
There was no statistically significant difference in pachymetry between cut and uncut corneas with increasing storage time up to one week. There was no statistically significant difference in percent devitalized cells between cut and uncut corneas with increasing storage time up to one week. There was a trend of greater loss of endothelial cells in the cut corneas that had been stored for 7 days compared to those stored for 1 day. This suggests that cutting corneas does affect the health of the endothelium, and that this damage becomes more evident with longer storage times.
Conclusions:
The implications of this study are important because if findings are confirmed, precut corneas can then be used for at least 5 days, without affecting the outcome of the DSAEK procedure. Precut corneas could be shipped/used over several days which would cut down on waste of donor tissue.
Keywords: cornea: storage • transplantation • cornea: clinical science