title: Type 1 Boston keratoprosthesis: outcomes at two Canadian centres.
abstract: OBJECTIVE
  To report the outcomes of patients who underwent Boston type 1 keratoprosthesis (Kpro) surgery at the University Health Network (Toronto, Ont.) and the University of Ottawa Eye Institute (Ottawa, Ont.) between June 2008 and July 2013.
  
  
  METHODS
  Retrospective case series.
  
  
  METHODS
  Forty-four eyes of 43 patients who underwent Kpro surgery.
  
  
  METHODS
  A retrospective review was conducted of all Kpro procedures performed by 4 attending cornea surgeons. The preoperative characteristics and postoperative course of each patient were analyzed.
  
  
  RESULTS
  In 31 eyes (70%), the primary indication for a Kpro was failed corneal transplantation. The remaining 13 eyes (30%) had Kpro as a primary procedure. In all eyes, preoperative visual acuity (VA) was 20/150 or worse, with 39 eyes (89%) having a VA of counting fingers, hand movement, or light perception. Mean follow-up time was 21 ± 12 months (range 12-57 months). The retention rate at the last follow-up was 95%. Best-achieved median VA was 20/100 (range 20/20 to no light perception [NLP]), with 37% of patients achieving a VA of >20/40 at some point during their postoperative course. At the last follow-up, median VA was 20/400 (range 20/30 to NLP). The 2 most common complications included retroprosthetic membrane formation (23 eyes, 52%) and elevated intraocular pressure (10 eyes, 23%). There were 5 cases (11%) of stromal melt and 1 case (2%) of infective keratitis.
  
  
  CONCLUSIONS
  This study demonstrates that Kpro improves VA in a majority of cases, and is a viable option in situations in which there is a poor prognosis for traditional penetrating keratoplasty.
authors.affiliation: Department of Ophthalmology, Toronto Western Hospital, University of Toronto, Toronto, Ont. Electronic address: christopher.noel@mail.utoronto.ca.
authors.forename: Christopher W
authors.initials: CW
authors.lastname: Noel
authors.affiliation: Department of Ophthalmology, Toronto Western Hospital, University of Toronto, Toronto, Ont.
authors.forename: Jordan
authors.initials: J
authors.lastname: Isenberg
authors.affiliation: Department of Ophthalmology, Toronto Western Hospital, University of Toronto, Toronto, Ont.
authors.forename: Yakov
authors.initials: Y
authors.lastname: Goldich
authors.affiliation: Ottawa Hospital Research Institute, University of Ottawa Eye Institute, Ottawa, Ont.
authors.forename: Ronan
authors.initials: R
authors.lastname: Conlon
authors.affiliation: Ottawa Hospital Research Institute, University of Ottawa Eye Institute, Ottawa, Ont.
authors.forename: Joshua
authors.initials: J
authors.lastname: Teichman
authors.affiliation: Department of Ophthalmology, Toronto Western Hospital, University of Toronto, Toronto, Ont.
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Rubinger
authors.affiliation: Department of Ophthalmology, Toronto Western Hospital, University of Toronto, Toronto, Ont.
authors.forename: Tessa A I
authors.initials: TA
authors.lastname: Weinberg
authors.affiliation: Department of Ophthalmology, Toronto Western Hospital, University of Toronto, Toronto, Ont.
authors.forename: Jaclyn
authors.initials: J
authors.lastname: Slomovic
authors.affiliation: Department of Ophthalmology, Toronto Western Hospital, University of Toronto, Toronto, Ont.
authors.forename: Clara C
authors.initials: CC
authors.lastname: Chan
authors.affiliation: Department of Ophthalmology, Toronto Western Hospital, University of Toronto, Toronto, Ont.
authors.forename: David S
authors.initials: DS
authors.lastname: Rootman
authors.affiliation: Ottawa Hospital Research Institute, University of Ottawa Eye Institute, Ottawa, Ont.
authors.forename: Kashif M
authors.initials: KM
authors.lastname: Baig
authors.affiliation: Department of Ophthalmology, Toronto Western Hospital, University of Toronto, Toronto, Ont.
authors.forename: Allan R
authors.initials: AR
authors.lastname: Slomovic
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001187:Artificial Organs; D001705:Bioprosthesis; D002648:Child; D002675:Child, Preschool; D003315:Cornea; D003316:Corneal Diseases / Q000601:surgery*; D016039:Corneal Transplantation; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D007431:Intraoperative Complications; D008297:Male; D008875:Middle Aged; D009864:Ontario; D011183:Postoperative Complications; D019919:Prosthesis Implantation; D012189:Retrospective Studies; D017211:Treatment Failure; D014792:Visual Acuity / Q000502:physiology*