Corneal sensation after descemet stripping and automated endothelial keratoplasty

To measure corneal sensation after Descemet stripping and automated endothelial keratoplasty (DSAEK).

Prospective comparative case series involving 52 eyes of 29 patients in the early postoperative period (<6 months) after small-incision DSAEK. Patients' contralateral eye served as a control. The sample size calculation was calculated assuming an alpha error of 0.05 and a beta error of 0.2. This determined that a sample size of 11 patients would be sufficient to detect a difference in corneal sensation of 5 mm as measured with the Cochet-Bonnet esthesiometer. The nylon filament was used to measure threshold sensation at 9 points on the operative eye and 5 points on the control. The data were analyzed using the paired samples test.

Although the results demonstrated mild hypesthesia of the corneal epithelium overlying the donor lenticule, we found no statistically significant difference in corneal sensation at the central point when comparing the DSAEK cornea with the control (57 vs 59 mm, P = 0.13.) In addition, when comparing corresponding points on the epithelium overlying the DSAEK graft and host cornea, no significant difference was found (57 vs 58 mm, P = 0.32). A difference was detected when comparing the average corneal sensation of the DSAEK eye with the control, but careful analysis of the data shows that this was driven by the slight decrease in sensitivity at the temporal incisional point (57 vs 59 mm, P = 0.002).

The results of this prospective study demonstrate the relative preservation of corneal sensitivity after DSAEK. Preservation of corneal sensation may provide another advantage of DSAEK over traditional penetrating keratoplasty.