Study: Osteo-odonto-keratoprostheses have better 10-year functional results

While osteo-odonto-keratoprostheses yielded better anatomical results than osteo-keratoprostheses at 2 years postop, the difference was not statistically significant at 10 years postop, a large chart review found. Conversely, functional results for both techniques were not significantly different at the 2-year follow-up but achieved significant differences at 10 years, the authors noted.

"However, this difference was influenced by the retinal potential and not by the technique itself," the study authors said in the August issue of Graefe's Archive for Clinical and Experimental Ophthalmology.

Rafael I. Barraquer, MD, an OSN Latin America Edition Editorial Board Member, and colleagues analyzed functional and anatomical results for 227 patients who received a keratoprosthesis using tooth and tibial autografts at the Centro de Oftalmología Barraquer in Barcelona, Spain. Specifically, 82 patients received an osteo-keratoprosthesis (group one) and 145 patients received an osteo-odonto-keratoprosthesis (group two). Functional success was defined as a best corrected visual acuity greater than 0.05; anatomical success was defined as retention of the keratoprosthesis lamina.

Mean follow-up time was 3.5 years for group one and 8.4 years for group two.

Based on Kaplan-Meier analyses, 10-year anatomical survival was 66% for patients in group two and 47% for patients in group one.

At 2 years follow-up, functional survival was 63% for patients in group two and 49% for patients in group one; at 10 years, functional survival was 38% for patients in group two and 17% for patients in group one.

Multivariate analysis demonstrated that functional survival was not significantly influenced by either of the surgical techniques, primary diagnosis or age, the authors noted.

"However, a high maximum visual acuity ever reached postop decreased the risk for functional failure," they said.

At 2 years, mean BCVA was 0.33 for patients in group two and 0.28 for patients in group one, according to the study.