Long-term prognosis of repeat Type I Boston keratoprosthesis.

OBJECTIVE

The Boston Type I keratoprosthesis (B-KPro) is a synthetic corneal implant used to restore vision in cases of corneal blindness. While the B-KPro can achieve a visual acuity of better than 20/200, it is associated with a risk of implant failure. In cases of failure, a repeat B-KPro may offer another opportunity for vision restoration. This study aims to evaluate the long-term outcomes of patients undergoing repeat B-KPro after failure of the initial implant.

DESIGN

This is a retrospective cohort study.

PARTICIPANTS

Eighteen patients who underwent two B-KPro implantations in the same eye, with a mean follow-up period of 8.1 ± 4.6 years.

METHODS

The primary endpoints were the failure rate of the implant and visual acuity at the last follow-up.

RESULTS

The failure rate of the repeat B-KPro (11.11% at 5 years) was significantly lower than that of the first B-KPro (88.89% at 5 years) (p < 0.0001) for the repeat cohort. Visual acuity better than 20/200 was achieved in 30.09% and 24.07% of patients at 3 years and 6 years, respectively, following repeat B-KPro, similar to outcomes observed after the first B-KPro. The incidence of phthisis was higher after the repeat B-KPro, but the rates of hypotony, endophthalmitis, corneal melt, and extrusion were lower compared to the first B-KPro.

CONCLUSIONS

Repeat B-KPro can provide sustained visual acuity better than 20/200 after failure of the initial implant. Further studies with larger cohorts are needed to better understand the risks and benefits associated with repeat B-KPro.