Long-term outcomes of the MICOF keratoprosthesis surgery

Purpose: To evaluate long-term anatomical and functional outcomes of the MICOF keratoprosthesis to treat endstage corneal blindness. Design: Retrospective review of consecutive clinical case series. Participants: Between October 2000 and October 2015, at the Department of Ophthalmology of Chinese PLA General Hospital (PLAGH), a total of 132 eyes of 131 patients had undergone a MICOF keratoprosthesis implantation. Of those, 91 eyes of 90 patients were included in this study. Methods: Preoperative information, surgical procedures, and postoperative data were collected for each included eye. Main outcome measures: Best-corrected visual acuity (BCVA), keratoprosthesis retention, and significant postoperative complications were reported. Results: The most common indications for surgery were chemical or thermal burns (68.1%, 62 of 91 eyes) and explosive injury (12.1%, 11 of 91 eyes), followed by Stevens-Johnson Syndrome (10.0%, 9 of 91 eyes), Sjo spacing diaeresis gren's syndrome (4.4%, 4 of 91 eyes), mucous membrane pemphigoid (3.3%, 3 of 91 eyes) and multi-penetrating keratoplasty failure (2.2%, 2 of 91 eyes). The mean follow-up duration was 8.38 +/- 3.22 years (range: 5-17.25 years, median: 7.67 years). All patbients had a preoperative visual acuity of hand motions or worse. A MICOF keratoprosthesis significantly improved patients' visual function with bilateral end-stage corneal blindness. Postoperative visual acuity improved to 20/200 or better in 41 eyes (45.1%, of 91 eyes) and to 20/100 or better in 32 eyes (35.2% of 91 eyes) at the last follow-up visit. Preexisting glaucoma was present in 17 (18.7% of 91 eyes). The most common postoperative complications were overgrowth of the surface mucosa (31.9%, 29 of 91 eyes), glaucoma (25.3%, 23 of 91 eyes), retro-prosthetic membrane (15.4%, 14 of 91 eyes), keratoprosthesis device extrusion (15.4%, 14 of 91 eyes), superficial tissue thinning (14.3%, 13 of 91 eyes), endophthalmitis (13.2%, 12 of 91 eyes), titanium frame exposure (13.2%, 12 of 91 eyes), optical cylinder ante-displacement (13.2%, 12 of 91 eyes), cornea melting (7.7%, 7 of 91 eyes), retinal detachment (6.6%, 6 of 91 eyes) and aqueous humour leakage (2.2%, 2 of 91 eyes). 84.6% (77 of 91 eyes) of the eyes retained their initial keratoprosthesis at the latest follow-up. Conclusions: A MICOF keratoprosthesis is a reliable approach to rescue vision in end-stage corneal blinded patients and has better retention than a Boston Kpro TypeII.