SEPTEMBER 2016 | NUMBER 12
Comparing Repeat Donor Corneal Transplantation to Boston Keratoprosthesis in Patients with Previous Graft Failure Sumayya Ahmad, MD, and Esen Akpek, MD
Proportion
95%-CI
62 36 38 82 8 49 1676 11 17
210 86 99 150 27 90 2540 53 39
0.30 0.42 0.38 0.55 0.30 0.54 0.66 0.21 0.44
[0.23; 0.36] [0.31; 0.53] [0.29; 0.49] [0.46; 0.63] [0.14; 0.50] [0.44; 0.65] [0.64; 0.68] [0.11; 0.34] [0.28; 0.60]
3294
0.60 [0.59; 0.62] 0.42 [0.30; 0.56]
Fixed effect model Random effects model Heterogeneity: l-squared=96.1% tau-squared=0.1485, p<0.0001
0.2
0.3
0.4
0.5
0.6
42%
1.00
Total
0.75
Events
0.50
Al-Mezaine 2006 Bersudsky 2001 Kirkness 1990 Patel 2000 Randleman 2003 Rapuano 1990 Williams 2008 Yalniz-Akkaya 2009 Yildiz 2010
We performed a systematic review of published literature regarding repeat PK, as well as a review of a large multicenter cohort of patients who underwent KPro for previous graft failure to compare visual outcomes and complication rates. Continued on page 3
0.25
Study
corneal surgeons to proceed with a KPro. Common practice is to perform multiple donor corneal transplantations in these patients until there is no reasonable expectation that the graft will remain clear. This likely translates into decreased likelihood of restored vision.
80%
0.00
In 2013, when we became interested in the fate of repeat corneal transplantations, more than 46,000 corneal transplantations were performed in the United States. Repeat grafts accounted for the second most common indication for penetrating keratoplasty (PK), even though long-term outcomes are often poor. The Boston Type I keratoprosthesis (KPro) provides an alternative option to repeat PK. However, there are currently no guidelines to indicate which patients would be ideal candidates for a repeat PK versus a KPro. Despite the latest multi-center publications reporting favorable outcomes, there seems to be reluctance among
0
20
40 Time in Months
60
Penetrating Keratoplasty (PK)
Type 1 Boston Keratoprosthesis (KPro)
Table and graph showing the random effects analysis evaluating the proportion of patients with repeat grafts who achieved 20/200 or better vision at 2 years. CI = confidence interval.
Graph showing the probability of maintaining 20/200 or better vision with a Boston Type I KPro after graft failure at 2 years.
Ahmad S, Mathews PM, Lindsley K, Alkharashi M, Hwang FS, Ng SM, Aldave AJ, Akpek EK. Boston type 1 keratoprosthesis versus repeat donor keratoplasty for corneal graft Failure: A systematic review and meta-analysis. Ophthalmology. 2016 Jan;123(1):165-77.
A Boston Keratoprosthesis update from Harvard Ophthalmology / Massachusetts Eye and Ear