Prevalence and Impact of Cornea Guttata in the Graft After Penetrating Keratoplasty in Germany

Purpose: The aim of this study was to analyze the prevalence and severity of corneal guttata (CG) in grafts after penetrating keratoplasty (PKP) and to determine its clinical significance.

Methods: This retrospective study included 1758 PKP performed in 1522 patients. In total, 6662 postoperative endothelial images revealed the prevalence and severity of CG (divided into categories G0 without CG and G1-G3 with increasing severity). Origin of the graft, postoperative corneal thickness, visual acuity, pleomorphism, polymegethism, and endothelial cell density (ECD) were analyzed.

Results: CG was detected in 14.9% of the grafts within 9 months after PKP, most of them were low-grade G1 (13.6%). Grafts from Homburg/Saar showed significantly less CG cases compared with other eye banks ( P = 0.034). The mean corrected distance visual acuity (logMAR) did not differ between G1 (0.45 ± 0.31) and G0 (0.46 ± 0.31). The mean ECD was lower in G1 compared with G0 ( P < 0.001). The mean corneal thickness was higher in G3 (597 ± 101 μm) compared with G0 (541 ± 65 μm) ( P < 0.001). Pleomorphism and polymegethism were correlated with CG ( P < 0.001). A progression of CG severity was detected in 13.5% of the cases during a follow-up time of 25.0 ± 19.9 months.

Conclusions: Our study suggested that CG are transplanted in 14.9% of PKP, most of which are low-grade CG not affecting the visual acuity but already leading to an increase in corneal thickness, loss of ECD, and alteration of endothelial cell morphology. In 13.5% of the cases, a progression was demonstrated in the postoperative course.