APR 30, 2020
The authors report the short-term outcomes of the new keratoprosthesis device Lux for corneal blindness. The device combines aspects of the Boston keratoprosthesis type II and modified osteo-odonto-keratoprosthesis (MOOKP).
This is a retrospective review of 9 patients who underwent surgery with a new keratoprosthesis design between January 2017 and June 2018. All patients had severe visual impairment in both eyes and had received at least 1 previous keratoprosthesis in the affected eye. Each patient underwent a buccal mucosal membrane graft to cover the ocular surface; the graft was sutured around the PMMA cylinder of the device. Concomitant procedures included pars plana vitrectomy, lensectomy and iridectomy. Postoperative outcomes, BCVA, device retention and complications were examined.
The preoperative visual acuity was light perception in 7 patients and hand motion in 2 patients. After a mean follow-up of 18.7 months (range 7–28 months), all cases reached at least 20/200 and 2 eyes maintained 20/20 vision. There were no device extrusions, mucosal retraction or necrosis. One patient developed a retinal detachment and 3 had retroprosthetic membrane formation.
This was a limited retrospective study involving severely visually impaired patients with high risk of complications due to ocular surface disease and previously failed keratoprosthesis devices. This type of device is limited to a small group of patients with the most severe types of corneal blindness and preexisting eyelid disease. This preliminary study did not provide the long-term follow-up necessary to determine the safety of this device and how it compares to other keratoprosthesis devices.
The Lux device may be an option for patients with a unique type of corneal blindness who would not otherwise be a candidate for a Boston Keratoprosthesis type II due to eyelid pathology or have a cuspid tooth for a MOOKP. Another advantage of this technology is that it may promote cosmesis—with a more normal buccal mucosa, lack of proptosis common with MOOKP and no risk of bone resorption—while still allowing for complete lack of tear production.