Use of Boston Type I Keratoprosthesis as a Primary Corneal Procedure
Narrative Responses:
Purpose
To explore the possibility of using the Boston type I keratoprosthesis as a primary corneal procedure in eyes with corneal blindness, which are at high risk for failure with penetrating keratoplasty.
Methods
This was a retrospective, interventional case control study. Patients with chronic bilateral corneal blindness who underwent Boston type I keratoprosthesis between July 1, 2009 and May 15, 2013 were included in the study. 69 eyes of 67 patients underwent Boston type I keratoprosthesis in the study period. All the patients were divided into primary keratoprosthesis group or secondary keratoprosthesis group (those patients with prior limbal stem cell transplant or penetrating keratoplasty). The primary outcome measure was anatomical retention and improvement in best corrected visual acuity (BCVA). The secondary outcomes were the occurrence of complications.
Results
29 primary keratoprosthesis in 27 patients and 38 secondary keratoprosthesis in 36 patients were included for analysis. The mean age at the time of surgery was 32.24 ± 19.53 years and 39.64 ± 20.67 years in the primary and secondary keratoprosthesis group respectively. The anatomical retention rate was 73.9% ± 8.6% and 79.9% ± 6.9% one-year postoperatively in the primary and secondary keratoprosthesis group respectively, and was statistically comparable. The median logMAR (logarithm of minimal angle of resolution) BCVA (best corrected visual acuity) at 1 year postoperatively was 0.4 and 0.6 in the primary and secondary keratoprosthesis group.
Conclusion
Boston type 1 keratoprosthesis is a viable alternative to limbal stem cell transplantation and penetrating keratoplasty as a primary treatment modality in eyes with chronic bilateral end stage corneal disease.