Results from the Multicenter Boston Type 1 Keratoprosthesis Study

Purpose: To report indications, practices, complications, and outcomes from the first multicenter study on the Boston Type 1 keratoprosthesis. Design: Prospective, noncomparative, interventional case series. Participants: We analyzed 141 Boston Type 1 keratoprosthesis surgical procedures, from 17 surgical sites, done from January 2003 through September 2005 in 136 eyes of 133 patients. Methods: Forms reporting 70 preoperative, intraoperative, and postoperative parameters were collected and analyzed at a central data collection site (Cornea Consultants of Albany, Albany Medical College, Albany, New York). Main Outcome Measures: Visual acuity (VA) and keratoprosthesis survival. Results: Common preoperative diagnoses were graft rejection, in 73 eyes (54%) (average prior grafts, 2.24); chemical injury (20 eyes [15%]); bullous keratopathy (19 eyes [14%]); and herpes simplex virus keratitis (9 eyes [7%]). Additionally, 82 eyes (60%) had preoperative glaucoma. Preoperative best-corrected VA ranged from 20/100 to light perception, and was <20/200 in 96% of eyes. At an average follow-up of 8.5 months (range, 0.03-24; standard deviation, 6.1; median, 12), postoperative vision improved to ≥20/200 in 57%. Among eyes at least 1 year after the operation (62 eyes), vision was ≥20/200 in 56% of eyes and ≥20/40 in 23%. At an average follow-up of 8.5 months, graft retention was 95%. Severe visual loss or failure to improve from keratoprosthesis was usually secondary to comorbidities such as advanced glaucoma, macular degeneration, or retinal detachment. Conclusions: The Boston Type 1 keratoprosthesis seems, based on early follow-up, to be a viable option after multiple failed corneal grafts or in some situations of a poor prognosis for primary penetrating keratoplasty.