Lifelong experience of modified osteo-odonto-keratoprosthesis implantation over 50 years

AIMS: The osteo-odonto-keratoprosthesis (OOKP) is a biological implant indicated for the treatment of eyes affected by corneal blindness, not amenable for keratoplasty. The purpose of the study is to report the long-term outcomes of patients undergone Falcinelli's modified OOKP (MOOKP). METHODS: In this retrospective study, anatomical and functional survival rates were evaluated using Kaplan-Meier analysis, according to eye coverage (buccal mucosa vs skin). Best-corrected visual acuity (BCVA) was recorded before and after surgery along with intraoperative and postoperative complications. RESULTS: 310 eyes of 269 patients affected by corneal blindness underwent MOOKP and were followed up for 15.9±12.0 years (up to 45 years). Anatomical survival rates for eyes covered by buccal mucosa were 85.1% at 20 years (number at risk (n)=81) and 82.3% at 45 years (n=10). Functional survival rates were 70.7% at 20 years (n=74) and 56.5% at 45 years (n=7). Anatomical and functional survival rates for eyes covered by skin were 58.9% (n=3) and 37.0% (n=3) at 20 years, respectively. Survival rates were significantly lower for eyes covered by skin (p<0.001). Postoperative BCVA at the last follow-up visit was significantly higher compared with baseline (0.88±1.08 LogMAR vs 2.49±0.38 LogMAR; p<0.001). The most threatening complications were glaucoma (n=70, 22.6%), endophthalmitis (n=24, 7.7%), retinal detachment (n=20, 6.4%), instability/tilting/expulsion of the optical cylinder and expulsion of the prosthesis (n=24, 7.7%). CONCLUSIONS: MOOKP showed excellent long-term anatomical and functional survival rates. Visual acuity significantly improved as soon as 3 months postoperatively and remained unchanged in about two-thirds of patients throughout the entire follow-up.