Preliminary study of Boston keratoprosthesis in treatment of severe late stage ocular chemical burns

Abstract

To evaluate preliminary clinical outcome of Boston type I keratoprosthesis in ocular chemical burn patients. Six keratoprosthesis were implanted into 6 patients of bilateral blindness. Visual acuity in these patients before the operation was light perception and all of them were unsuitable for standard penetrating corneal transplantation. The causes for corneal opacity were alkali burn in 2, sulfate acid burn in 3 and ethanol injury in 1 patient. Shirmer's test revealed severe dry eye in 3 patients, only one eye had normal lacrimal secretion. All patients were male, with follow-up period ranged from 17 to 26 months (mean 24 months). The postoperative visual acuity ranged from 0.05 to 0.5, 5 of them was better than 0.1. The retention rate within the follow-up period was 100%. Intraocular pressure was in normal limit, no retinal detachment was detected by type B ultrasonic examination. Postoperatively, retro-keratoprosthestic membrane occurred in 2 cases and was treated with YAG laser membranectomy, one eye complicated with elevated intraocular pressure and treated with shunt implantation. The Boston type 1 keratoprosthesis is a viable option for patients with obsolete chemical burns.