Short-term visual outcomes of Boston keratoprosthesis type I in Saudi Arabia

Abstract

Purpose:To evaluate the visual outcomes, complications and retention of threadless type I Boston keratoprosthesis (KPro) in Saudi Arabia.Materials and Methods:Retrospective analysis of four eyes of four patients (one female and three males; age range: 48 to 72 years) who underwent Boston type I threadless KPro implantation between January and December 2009.Results:In the median follow-up of 11 months (range 6 to 14 months), visual outcomes were satisfactory. Preoperative diagnosis included two patients of post-trachoma dense vascularized corneal scarring, one patient of corneal alkali burn and one patient of repeated failed corneal grafts. All patients demonstrated significant improvement in vision; with pre-operative visual acuity of hand movements (HM), counting fingers and HM improved to best corrected visual acuity (BCVA) of 20/200, 20/60, 20/50 and 20/30 on their last follow-up visits respectively. None of the patients developed glaucoma as a result of the procedure. No retro-prosthetic membrane developed till the last follow-up visit. One of the four patients had a corneal melt (due to severe dryness associated with trachoma) 6 months after the KPro implantation and underwent a successful KPro revision. Despite the relatively poor prognosis expected in alkali burn eye, the patient attained the maximum BCVA (20/30) of the four eye series on the last follow-up visit at six months.Conclusion:In consistent with the earlier reports from other parts of the world, all the 4 eyes had a significant increase in vision after Boston type I KPro implantation. However, patients require close lifelong follow-up to manage any complications.

Boston keratoprosthesis – Clinical outcomes with wider geographic use and expanding indications – A systematic review

“…Even in the studies reporting larger dataset (136–300 eyes), retention rate of 93–95% is obtained 31,38 . Case series from Saudi Arabia and Jordan have also reported good retention rates (75–100%) 5,15,42 ; it is important to note that despite the arid climate of this region, which contributes to the ocular surface dryness, the retention rate reported in this study is consistent with the reports from other parts of the world.…”

“…While several studies reported achieving CDVA of 20/50 or better in at least some of the eyes 4 papers reported achieving CDVA of 20/50 or better in 43–60% of their dataset 10,11,17,41 . Visual acuity in case series from arid climatic conditions of Saudi Arabia and Jordan also reported good visual outcomes with 65–100% of the eyes achieving CDVA of 20/200 or better and 0–25% of the eyes achieving visual acuity of 20/50 or better 5,15,42 which are comparable to those from the US (with 20–81% of the eyes achieving CDVA of 20/200 or better and 0–48% of the eyes achieving CDVA of 20/50 or better).…”

“…Literature review also seems to suggest that indication of primary B-KPro implantation (KPro implantation performed without first attempting keratoplasty) included eyes with severe ocular surface damage due to chemical or thermal injury (percentages varying from 7% to 30.4% in different studies) (Table 1) 9,11,15–17,31–35 or autoimmune diseases such as SJS (2.5–100%) 8–11,16,34,35 or congenital anomalies such as aniridia (1–100%) 12,17,23,34–37 . While bullous keratopathy and aniridia were reported commonly in the studies from the US and Canada, post-trachomatous scarring 15 was the most common indication from Saudi Arabia (Fig. 1) and chemical injury was the common indication internationally 7,12,13,16,17,20,23,34,38 .…”

“…India, Nepal, Indonesia etc.) 5,12,15–17 . Since the causes of corneal blindness necessitating B-KPro implantation vary with different geographical locations and climatic conditions newer indications for B-KPro implantation (e.g.…”

High MMP-9 Expression May Contribute to Retroprosthetic Membrane Formation after KPro Implantation in Rabbit Corneal Alkali Burn Model

“…The Boston Type 1 keratoprosthesis (KPro), developed at the Massachusetts Eye and Ear Infirmary and approved by the US Food and Drug Administration (1993), is currently the most commonly used keratoprosthesis worldwide [ 4 ] and is used in cases at high risk for penetrating keratoplasty failure [ 5 ]. It has been successfully used to restore vision in cases of chronic corneal disease and graft failure, including corneal alkali burn [ 6 ]. However, despite multiple advances and improvements in prognosis of patients following KPro surgery, several challenges remain.…”