Retinal Detachment Risk After B1KPro Surgery

Retinal detachment (RD) is a serious complication associated with the implantation of the Boston Type 1 Keratoprosthesis (B1KPro), often leading to permanent visual acuity loss in a significant number of cases.

A recent study conducted by researchers from Spain and Croatia aimed to identify risk factors for early and late-onset RDs following B1KPro surgery. The study, led by Eva Calpe, PhD, from the Centro de Oftalmología Barraquer and the Institut Universitari Barraquer, Universitat Autònoma de Barcelona, found that risk factors for RD differed between the early and late postoperative periods.

Study Overview

The research team performed a retrospective cohort study involving 94 eyes (90 patients) who underwent B1KPro implantation at the Centro de Oftalmología Barraquer between June 2006 and July 2022. All patients had a minimum follow-up period of one year.

Key Findings and Incidence of Retinal Detachment

The study revealed that the overall incidence of RD following B1KPro implantation was 29% (27/94 cases).

• Early-onset RD (within the first year) occurred in 21% of eyes.

• Late-onset RD (after one year post-surgery) was observed in 7% of eyes.

Risk Factors for Early and Late Retinal Detachment

Early-Onset Retinal Detachment (First Year Post-Surgery)

Significant risk factors for early RD development included:

• Hypotony (low intraocular pressure) – 84% of cases (16/19); odds ratio (OR) = 14.5, P < 0.0001

• Aphakia (absence of the natural lens) – 80% of cases (16/20); OR = 5.9, P = 0.004

• Intraocular lens (IOL) removal – 50% of cases (4/8); OR = 6.2, P = 0.03

• Previous choroidal detachment (CD) – 35% of cases (7/20); OR = 35.5, P = 0.001

• Pars plana vitrectomy (PPV) at any time – 75% of cases (15/20); OR = 6.6, P = 0.006

Late-Onset Retinal Detachment (After One Year Post-Surgery)

Cases of RD occurring after the first year were significantly associated with:

• Peripheral retinal changes detected a few days before vision loss and RD diagnosis – 66% of cases (4/6); OR = 65, P < 0.0001

Conclusions and Clinical Implications

Dr. Calpe and her colleagues concluded that risk factors for RD after B1KPro implantation differ between early and late postoperative periods.

• Hypotony emerged as a primary risk factor for early RD development, alongside previous choroidal detachment, PPV, aphakia, and IOL removal.

• Late-onset RD was strongly correlated with peripheral retinal changes detected shortly before vision loss.

The study underscores the importance of frequent intraocular pressure monitoring and comprehensive retinal assessments over time to mitigate the risk of RD in patients undergoing B1KPro implantation.

Reference:

Calpe E, Fernández-Engroba J, Julio G, et al. Risk factors for early and late retinal detachment after Boston Type I keratoprosthesis surgery. Graefes Arch Clin Ophthalmol.