Boston keratoprosthesis outcomes and complications

To evaluate the outcomes of the Boston Keratoprosthesis (KPro) at our institution.

A computerized database retrospectively identified all patients who received a Boston KPro from August 2005 to October 2007.

There were 37 patients, 24 (65%) were male. Mean age was 66.3 years (median 69 years, range: 24-93 years; SD = 18.1 years). Mean follow-up was 16 months (range: 6-28 months; SD = 6.0 months). There were 36 type 1 (97%) and 1 type 2 (3%) KPros. The primary indication was failed penetrating keratoplasty in 29 patients (78%)-22 (59%) from multiple failures. Preoperative comorbidities included glaucoma [27 patients (73%)] and limbal stem cell deficiency [13 patients (35%)]. No intraoperative complications occurred. Postoperative complications included retroprosthetic membrane [24 patients (65%)], increased intraocular pressure [14 patients (38%)], glaucoma progression [5 patients (13.5%)], and endophthalmitis [4 patients (11%)-3 who discontinued prophylactic antibiotics secondary to compliance]. Thirty-six KPros (97%) were retained-1 type 2 KPro (3%) in a patient with ocular cicatricial pemphigoid extruded and was replaced. Mean best-corrected visual acuities were counting fingers preoperatively (range: light perception to 20/100) and 20/90 at last follow-up (range: light perception to 20/25). At last follow-up, 31 patients (84%) improved 2 lines or greater-3 patients (8%) had worse vision.

Retention rates were excellent, and best-corrected visual acuities improved in the vast majority of patients. Complications can occur and require frequent follow-up to monitor and treat glaucoma progression, endophthalmitis, and inflammation. Patient compliance is of paramount importance. Despite the potential complications, the Boston KPro provides visual improvement in patients with an otherwise poor prognosis.