Intraocular Light Scatter in Eyes with Boston Type 1 Keratoprosthesis

Purpose: 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 complain of debilitating glare despite attaining good visual acuities. This motivated us to objectively measure light scatter in eyes with KPro. Methods: Light scatter was measured in 21 eyes with Boston KPro Type 1 with VA of 20/150 or better and was compared to 13 healthy control eyes using OCULUS C-Quant device (Arlington, WA). Eyes were also measured with the use of an occluder contact lens. Results: Light scatter (quantified as logS value) was significantly higher in the KPro group compared to the control (2.34 ± 0.15 vs. 1.29 ± 0.17, p < 0.001). PMMA KPro (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 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 due to its opaque nature, the titanium backplate model appears to produce less light scatter than PMMA model. Occluder contact lenses reduced the light scatter significantly in PMMA KPro and could be a treatment option for symptomatic patients.