Tandem scanning confocal microscopy of cornea after descemet stripping automated endothelial keratoplasty

PURPOSE: To evaluate the changes in the corneal stroma after Descemet stripping automated endothelial keratoplasty (DSAEK) using tandem scanning confocal microscopy (CM). METHODS: Thirteen eyes of 13 patients who underwent DSAEK without preoperative corneal haze or scar obvious at the slit lamp, any ocular disease, and postoperative complication were included in the study. All patients were examined clinically and by CM 6 months after DSAEK. RESULTS: Six months after DSAEK, none of the eyes had clinically significant interface haze (i.e., haze affecting quantity or quality of vision) at slit lamp. The mean best spectacle corrected visual acuity was 0.18 ± 0.12 (range 0-0.4) logMAR (Snellen 20/30). The CM revealed highly reflective particles in interface in six eyes, particles with mild surrounding increased reflectivity in four eyes, and no discernible interface in three eyes. The mean particles density at interface was 28.6 ± 23.4 particles/mm. No significant keratocyte activation was seen in any case at the interface. The mean anterior stromal reflectivity was 431.2 ± 269.1 confocal back scatter units (CBU) and the mean interface reflectivity was 65.9 ± 46.9 CBU. The mean anterior stromal reflectivity was significantly greater than the mean interface reflectivity (P<0.01). Significant keratocyte activation with high reflectivity was seen in superficial anterior stroma in 8 of 13 eyes. CONCLUSIONS: Tandem scanning CM shows the presence of highly reflective particles at the level of the DSAEK interface that are morphologically similar to a laser in situ keratomileusis interface. The stromal reflectivity is more prominent in subepithelial layers than that of interface 6 months after DSAEK. However, the areas under the mean reflectivity peaks (CBU) corresponding to the flap interface and superficial anterior stroma do not seem to correlate with best spectacle corrected visual acuity results after the procedure.