Purpose:
The authors are trying to identify the ideal characteristics of the corneal grafts susceptible to be used for Descemet Stripping Automated Endothelial Keratoplasty (DSAEK). According to these characteristics, they are further describing an adapted, replicable and easily transposable method of corneal removal.
Methods:
The corneas included in this laboratory study were specimens rejected by the tissue bank for low endothelial density or transmissible pathology. 30 corneas were tested according to their dimensions and followed a procedure similar to the standard surgical DSAEK protocol. There were noted, for each cornea, the corneal diameter, the minimum scleral border size and the total diameter of the complex cornea + scleral borders. The fitting on the artificial chamber (Moria laboratory, France), obtaining a pressure of 70 mm Hg, was evaluated as possible or not, accordingly to the dimensions of each graft.
Results:
For the 30 grafts tested, the average corneal diameter was 11.76 +/- 0.60 (Range between 10 and 13 mm), the average of the minimum scleral border size was 2.21+/- 0.51 (Range between 0.5 and 4 mm) and the average total corneal - scleral diameter was 16.62 +/- 1.62 (Range between 12 and 22 mm). The procedure was successfully completed in 22 cases (73.33%). All of the 8 corneas for which the procedure’s realization was not possible had a total corneal-scleral diameter inferior to 15 mm and 3 of them had a scleral border size inferior to 1 mm. The grafts’ centering on the artificial chamber turned to be more difficult in the cases with irregular margins, but a leak free sealing was nevertheless possible.
Conclusions:
The essential condition that the graft must fulfill in order to be fitted perfectly on the artificial chamber is a total diameter of at least 15 mm (complex cornea + scleral border). 73.33% of the corneas were validated according to our criteria. We consequently recommend the usage of a minimum 15 mm total diameter corneal graft, with smooth and regular scleral borders. A 15mm disposable trephine or a 15 mm disposable scleral marker could therefore provide these ideal grafts.
Keywords: cornea: clinical science • transplantation