Incidence, Risk Factors, and Surgical Management of Boston Type 1 Keratoprothesis Corneal Melts, Leaks, and Extrusions

Purpose: To determine the rate of Boston type 1 keratoprosthesis (Kpro)-related corneal melts, leaks, and extrusions requiring surgical repair and to analyze possible risk factors and visual outcomes. Methods: Retrospective chart review of 110 patients (128 eyes) who received a Kpro between November 2004 and December 2010 (average follow-up of 29 mo). The rate of corneal complications, risk factors for melts, and postmelt repair visual outcomes were evaluated. Results: Twenty eyes from 18 patients developed Kpro-related melts requiring surgical repair. The incidence of melt-related complications was 16%. In total, there were 33 episodes of meltrelated complications. Surgical repair included lamellar patch grafts (15), Kpro removal with penetrating keratoplasty (7), reassembly of Kpro onto a new cornea (4), replacement of Kpro (3), suturing of a leak (3), and enucleation (1). The majority of eyes (18/20) did not regain their best post-Kpro vision at final follow-up (average 10 mo and range, 1-36 mo after melt repair). Significant risk factors for melt included previous infectious keratitis [P < 0.0001, odds ratio (OR) = 12.50, 95% confidence interval (CI), 4.02-38.9] and conjunctival deficiency (ie, a diagnosis of Stevens-Johnson syndrome, mucous membrane pemphigoid, or chemical injury, P = 0.043, OR = 2.66, CI, 1.01-7.02). Conclusions: Patients who undergo Kpro with severe ocular surface disease are at greater risk for corneal melts, leaks, and extrusions. Patients with infectious keratitis and conjunctival deficiency are at an increased risk of developing corneal melts. Visual outcomes are poor after surgical repair of these complications.