Intraocular Light Scatter in Eyes with the Boston Type 1 Keratoprosthesis

Abstract

Purpose: The Boston keratoprosthesis (KPro) is the most commonly used artificial cornea. It has been proven to be successful for severe corneal disease not amenable to keratoplasty. We have observed our patients reporting debilitating glare despite attaining good visual acuities. This motivated us to objectively measure light scatter in eyes with a KPro. Methods: Light scatter was measured in 21 eyes with the Boston type 1 KPro with a VA of 20/150 or better and was compared with 13 healthy control eyes using the Oculus C-Quant device (Arlington, WA). Eyes were also measured using an occluder contact lens. Results: Light scatter (quantified as the logS value) was significantly higher in the KPro group than in the control (2.34 ± 0.15 vs. 1.29 ± 0.17, P , 0.001). The polymethylmethacrylate (PMMA) KPro group (16 eyes, logS 2.49 ± 0.19) but not the titanium group (5 eyes, logS 1.87 ± 0.15) had significantly higher light scattering than the control. The use of an occluder contact lens significantly decreased light scatter in eyes with a PMMA backplate (n = 11, logS 1.71 vs. 2.42, P = 0.028). Conclusion: This study confirms that intraocular light scatter is increased in KPro eyes. Possibly because of its opaque nature, the titanium backplate model seems to produce less light scatter than does the PMMA model. Occluder contact lenses reduced light scatter significantly in the PMMA KPro and could be a treatment option for symptomatic patients.