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

Abstract

Over 2 decades of research, several design modifications, and improvements in post-operative management have made Boston keratoprosthesis (B-KPro) a viable option for patients with corneal blindness for whom traditional keratoplasty procedure has a very low probability of success. In this systematic review, we examined the indications, visual outcomes, complications and retention rate of the literature published in the past 10 years (2005-2014). While most of the studies report smaller datasets (typically <50 eyes), some of the recent multicenter studies have reported large datasets (up to 300 eyes). Most of the literature is published from the US; however, last few years have witnessed some papers reporting the successful use of B-Kpro from developing countries or arid climatic conditions (such as the Kingdom of Saudi Arabia). Due to differences in the causes of corneal blindness in different geographic regions, newer indications for B-Kpro are emerging (e.g. trachoma). Additionally, improving clinical outcomes and increasing surgeon confidence have also expanded indications to include cases of unilateral visual impairment and paediatric age. We observed that there is growing body of evidence of successful clinical use of B-KPro; however, financial challenges, lack of trained surgeons, shortage of donor corneas must be overcome to improve accessibility of B-KPro.

Boston keratoprosthesis type 1: outcomes of the first 38 cases performed at Moorfields Eye Hospital

“…This was clearly understood by our patients and it was appreciated that any potential improvement in vision, even if temporary, was considered a worthwhile outcome. Best outcomes were seen in patients who had no posterior segment disease (i.e., glaucoma, retinal disease or detachments), where vision was maintained at 6/15, in line with the international literature [5][6][7][8][9]. The anterior segment pathology was not an independent variable; however, complex anterior segment disease often had concomitant glaucoma, which affected final outcomes.…”

Sputter Deposition of Titanium on Poly(Methyl Methacrylate) Enhances Corneal Biocompatibility

“…The Boston Keratoprosthesis (BK) is a medical device indicated for patients with corneal blindness not amendable to standard corneal transplantation. [1][2][3][4][5][6][7][8][9][10][11][12] The BK is composed of a front plate/stem (optical portion) made of poly(methyl methacrylate) (PMMA) and a back plate made of PMMA or titanium (Ti), assembled in bolt (PMMA front plate/stem) and nut (Ti back plate) fashion within a donor cornea that serves as a carrier; the donor cornea is sutured to the eye as in standard corneal transplantation. [13][14][15] The BK is globally the most commonly implanted artificial cornea.…”

Intrinsic Optical Properties of Boston Keratoprosthesis

“…The surgical and clinical outcomes of patients implanted with the B-KPro have been previously published to elucidate the clinical performance of the device, 8 , 9 and help surgeons optimize patient selection and reduce postoperative surgical complications. A few studies have detailed the optical performance of the B-KPro, 10 – 12 however, a detailed evaluation of the intrinsic optical performance of the B-KPro simulating an aqueous environment has not been performed to International Organization for Standardization (ISO) standard bench-top methods.…”