Vitritis after Boston Keratoprosthesis Type 1 Implantation

To describe the incidence, presentation, and clinical course of vitritis occurring after Boston keratoprosthesis type 1 implantation.

Retrospective chart review.

Medical records of all patients undergoing type 1 Boston keratoprosthesis implantation over a 4-year period were reviewed.

Cases of vitreous inflammation were classified as either postoperative (within 1 month after surgery without endophthalmitis), reactive (secondary to ocular surface inflammation), idiopathic, or infectious endophthalmitis. The presenting features and postoperative course of all patients were reviewed.

Postoperative inflammation.

A total of 110 eyes underwent type 1 Boston keratoprosthesis implantation with a median follow-up of 5.6 years. Overall, there were 21 episodes of vitritis occurring in 17 patients; 6 cases of vitritis were postoperative, whereas 5 were reactive, 7 were idiopathic, and 3 were infectious endophthalmitis. Patients with vitritis sought treatment a median of 10 months after surgery (range, 1 week-7 years). Compared with patients in whom vitritis did not develop, those with vitritis were younger (50.8 years of age vs. 62.2 years of age; P = 0.01), but with a similar prevalence of autoimmune disease (P = 1.00). Eyes with postoperative vitritis had a benign and short course, and were all managed with topical medications. Reactive vitritis occurred in association with infectious keratitis (4 cases) or corneal melting (1 case). Patients with idiopathic vitritis and endophthalmitis demonstrated similar symptoms of pain and severe vision loss. The mean duration of inflammation in patients of idiopathic vitritis was 3.3 months; all patients later demonstrated retroprosthetic membrane, and 2 patients (29%) demonstrated retinal detachment. Three of 7 patients with idiopathic vitritis underwent a vitreous tap, which showed negative results in all cases. The 3 cases of infectious endophthalmitis had a prolonged and severe course, with only 1 eye retaining functional vision.

Patients undergoing type 1 Boston keratoprosthesis implantation are at risk of postoperative vitreous inflammation, which may present in the immediate postoperative period or years later. Cases of idiopathic inflammation may present similarly to infectious endophthalmitis, and a low threshold should be taken for performing vitreous tap and injection of antimicrobials. Caution should be exercised using sub-Tenon corticosteroids, given the high prevalence of glaucoma and possibility of exacerbating fungal infections.