Lucia and Beyond: Development of an Affordable Keratoprosthesis.

Abstract

Severe corneal disease contributes significantly to the global burden of blindness. Corneal allograft surgery remains the most commonly used treatment, but does not succeed long term in every patient, and the odds of success fall with each repeated graft. The Boston keratoprosthesis type I has emerged as an alternative to repeat corneal allograft. However, cost limits its use in resource-poor settings, where most corneal blind individuals reside. All aspects of the Boston keratoprosthesis design process were examined to determine areas of potential modification and simplification, with dual goals to reduce cost and improve the cosmetic appearance of the device in situ. Minor modifications in component design simplified keratoprosthesis manufacturing. Proportional machinist time could be further reduced by adopting a single axial length for aphakic eyes, and a single back plate diameter. The cosmetic appearance was improved by changing the shape of the back plate holes from round to radial, with a petaloid appearance, and by anodization of back plate titanium to impute a more natural color. We have developed a modified Boston keratoprosthesis type I, which we call the "Lucia." The Lucia retains the 2 piece design and ease of assembly of the predicate device, but would allow for manufacturing at a reduced cost. Its appearance should prove more acceptable to implanted patients. Successful keratoprosthesis outcomes require daily medications for the life of the patient and rigorous, frequent, postoperative care. Effective implementation of the device in resource-poor settings will require further innovations in eye care delivery.