Twelve-Month Visual and Anatomical Outcomes of Boston Type I Keratoprosthesis in Four Patients with Multiple Graft...

To assess 12-month visual acuity, anatomic integrity, and complication rates after Boston Type I Keratoprosthesis (BKPro-I) implantation in eyes with multiple failed penetrating keratoplasties and complex anterior segment pathology.

In this prospective case series, four eyes (mean age, 32 ± 9 years) received BKPro-I between January and June 2022. All surgeries employed polymethylmethacrylate front plates, customized titanium back plates, and a standardized perioperative regimen (IV cefazolin, topical vancomycin + levofloxacin, corticosteroid taper, nightly povidone-iodine, selective antifungal prophylaxis) with early 16 mm scleral lens fitting. Follow-up occurred at 3 days, 1 week, 2 weeks, monthly to 3 months, then quarterly to 12 months postoperatively. Primary outcomes were best-corrected visual acuity (BCVA), device retention, and sight-threatening complications.

At 12 months, all devices were retained. Functional success (BCVA ≥20/200) was achieved in 100% of eyes in 6 months; at 12 months, 75% reached ≥20/100 and 50% ≥20/60 (mean gain ≥5 ETDRS lines). Two eyes (50%) developed complications - retroprosthetic membranes, vitritis/suspected endophthalmitis, stromal melting, chronic hypotony, and silicone-oil leak - all managed without device loss; one eye's vision declined to finger counting at month 7 but remained ambulatory.

BKPro-I yields excellent short-term visual rehabilitation and perfect retention in highly complex eyes. However, a 50% complication rate mandates rigorous patient selection, standardized perioperative protocols, and lifelong multidisciplinary follow-up.