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Published on: August 25, 2023
Outcomes of Boston keratoprosthesis type 1 reimplantation: multicentre study results
Jay C Wang1, Christopher J Rudnisky2, Michael W Belin3
1Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA.
Objective:
To investigate the visual and anatomical outcomes of Boston keratoprosthesis (Kpro) type 1 reimplantation.
Design:
Subgroup analysis of multicentre prospective cohort study.
Participants:
Of 303 eyes that underwent Kpro implantation between January 2003 and July 2008 by 1 of 19 surgeons at 18 medical centres, 13 eyes of 13 patients who underwent reimplantation of Boston Kpro type 1 were compared with 13 eyes of 13 diagnosis-matched patients who underwent initial implantation.
Methods:
Forms reporting preoperative, intraoperative, and postoperative parameters were prospectively collected and analyzed. Main outcome measures were Kpro retention and logMAR visual acuity.
Results:
After a mean follow-up time of 17.1 ± 17.6 months, the retention of both initial and repeat Kpro implantation was 92.3% (12/13 in both groups), and 62% of initial implantation and 58% of repeat implantation eyes achieved visual acuity better than 20/200. Vision worse than 20/200 was often due to glaucoma or posterior segment pathology. Best-recorded logMAR visual acuity was significantly improved postoperatively in both groups (p < 0.001), and there was no statistically significant difference in final logMAR visual acuity between the 2 groups (p = 0.89). Sterile keratolysis (n = 4) and fungal infection (n = 5) were the most common causes of initial Kpro failure in the repeat Kpro group. The single failure in the repeat Kpro implantation group was due to fungal keratitis, and in the control group it was related to Kpro extrusion.
Conclusions:
Repeat Kpro implantation is a viable option after failed initial Kpro, with visual and anatomical outcomes comparable to those of initial procedures.
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