Idiopathic Vitritis after Boston Type 1 Keratoprosthesis Implantation: Incidence, Risk Factors and Outcomes in a Multicentric Cohort.

Purpose: To determine incidence, risks factors for, and outcomes of idiopathic vitritis (IV) after Boston type 1 keratoprosthesis (KPro) implantation.
Methods: Retrospective, consecutive case series. Risk factors were analyzed between IV group and No IV group.
Results: IV occurred in 32/350 procedures (9.1%), for an average incidence of 0.02 cases per procedure-year. Presumed infectious keratitis was the only risk factor identified (HR = 7.65) Corneal necrosis and retinal detachment occurred significantly more frequently in IV group (all P < .05). By last follow-up, the cumulative proportion of eyes that maintained a visual acuity >20/200 was significantly lower in IV group ( P = .01), as was the KPro retention rate (HR = 0.26).
Conclusions: IV is associated with infectious keratitis, indicating that the vitritis may not be a sterile process. The increased incidence of subsequent complications leads to significantly decreased visual acuity and KPro retention in affected eyes.