Eight-years Egyptian experience of Boston type I keratoprosthesis following failed penetrating keratoplasty or ocular surface disease

PURPOSE: To evaluate the outcome and complications after implantation of the Boston type I keratoprosthesis (Kpro) in two groups of eyes. METHODS: We retrospectively reviewed records of 28 eyes with failed Penetrating keratoplasty (PKP) (Group A) and 31 eyes with severe ocular surface diseases who implanted Kpro. Follow-up was performed for a mean 37 months. Primary outcomes were Kpro retention and visual improvement, secondary outcomes included the occurrence of complications as endophthalmitis, retro-prosthesis membrane (RPM), intraocular pressure (IOP) abnormalities, posterior capsule opacification (PCO), graft thinning and extrusion. RESULTS: Visual improvement was achieved in 20 eyes in Group A, and in 19 eyes in Group B. In group A, the prosthesis was retained in 25 eyes, while prosthesis retention in Group B was in 26 eyes. Group A had higher rates of PCO, high IOP, soft IOP, and graft thinning. Group B had higher risk of RPM, and endophthalmitis. Two eyes in Group A, and Five eyes in Group B required redo procedure. CONCLUSION: The Boston Kpro type I is an effective procedure in eyes with high risk of keratoplasty failure and in severe ocular surface diseases, it has a high retention rate, higher in cases following failed PKP.