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Comparative Outcomes of Boston Keratoprosthesis Type 1 Implantation Based on Vision in the Contralateral Eye
Swapna S Shanbhag1, Hajirah N Saeed1, Kathryn A Colby2
1Massachusetts Eye and Ear, Harvard Medical School, Boston, MA.
Purpose:
To compare the outcomes of Boston keratoprosthesis type 1 implantation after failed keratoplasty in patients who are blind or sighted in the contralateral eye.
Methods:
Retrospective comparative case series of Boston keratoprosthesis type I recipients performed for failed keratoplasty, between January 1, 2008, and June 30, 2016, at a single center. Patients were divided based on the best-corrected visual acuity in the contralateral eye at the time of surgery: group I, ≤20/200, and Group II, >20/200. Preoperative diagnoses, postoperative visual acuity, device retention, and postoperative complications were compared.
Results:
Group I (37 eyes) and group II (36 eyes) had similar demographics, median preoperative best-corrected visual acuity (count fingers) in the operated eye, and median duration of postoperative follow-up (37.4 vs. 45.2 months, respectively). Keratoprosthesis retention after the first year postimplantation was significantly better in group I versus group II (P = 0.038). Sterile vitritis and sterile keratolysis occurred more frequently in group II compared with group I (P = 0.013 and P = 0.056, respectively). At final examination, visual outcomes were not significantly different between the 2 groups.
Conclusions:
Most patients with failed keratoplasty who were implanted with a Boston keratoprosthesis type I experienced improved vision, and visual acuity of the contralateral eye did not seem to influence the visual outcome of surgery. However, patients with good vision in the contralateral eye were more likely to experience complications, possibly because of reduced vigilance when the other eye has ambulatory vision.
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