title: International results with the Boston type I keratoprosthesis.
abstract: OBJECTIVE
  To determine the indications and outcomes of Boston type 1 keratoprosthesis (Massachusetts Eye and Ear Infirmary, Boston, MA) surgery performed outside of North America and to compare them with those obtained in the United States by the surgeon who trained the international surgeons.
  
  
  METHODS
  Retrospective review of consecutive clinical case series.
  
  
  METHODS
  One hundred ninety-four patients (223 keratoprosthesis procedures performed in 205 eyes) who received Boston type 1 keratoprosthesis at 11 ophthalmology centers in Armenia, India, Indonesia, Nepal, Philippines, Russia, and Saudi Arabia between May 1, 2006, and July 1, 2011 (international series), and at the Jules Stein Eye Institute between May 1, 2004, and July 1, 2011 (University of California, Los Angeles [UCLA] series).
  
  
  METHODS
  Data were collected for each procedure regarding the preoperative characteristics of each eye, the surgical procedure(s) performed, and the postoperative outcomes. Statistical analysis was performed to identify significant differences between the international and UCLA series in terms of retention and complications.
  
  
  METHODS
  Interval visual acuities, keratoprosthesis retention, and significant postoperative complications.
  
  
  RESULTS
  In the international series, 113 Boston type I keratoprostheses were implanted in 107 eyes of 100 patients. The most common indication for surgery was corneal graft failure (n = 50; 44%) followed by chemical injury (n = 30; 27%). Although only 2% of eyes had a preoperative corrected distance visual acuity (CDVA) of 20/20 to 20/200, 70%, 68%, and 59% of eyes had a postoperative CDVA of 20/20 to 20/200 at 6 months, 1 year, and 2 years after surgery, respectively. Ninety-one of the 113 keratoprostheses implanted (80.5%) were retained at a mean follow-up of 14.2 months, for a retention failure rate of 22 per 134.6 eye-years (0.163/eye-year). The most common postoperative complications were retroprosthetic membrane formation (27%) and sterile corneal necrosis (18%). The only postoperative complication that was more common in the international series than in the UCLA series was infectious endophthalmitis, which developed in 9% of eyes.
  
  
  CONCLUSIONS
  Boston keratoprosthesis is a viable means of managing repeat graft failure and ocular chemical injury outside of North America, with similar visual acuity outcomes, retention rates, and incidence rates of postoperative complications to those obtained by North American surgeons.
authors.affiliation: The Jules Stein Eye Institute, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California, USA. aldave@jsei.ucla.edu
authors.forename: Anthony J
authors.initials: AJ
authors.lastname: Aldave
authors.forename: Virender S
authors.initials: VS
authors.lastname: Sangwan
authors.forename: Sayan
authors.initials: S
authors.lastname: Basu
authors.forename: Samar K
authors.initials: SK
authors.lastname: Basak
authors.forename: Anna
authors.initials: A
authors.lastname: Hovakimyan
authors.forename: Ofelya
authors.initials: O
authors.lastname: Gevorgyan
authors.forename: Soliman Al
authors.initials: SA
authors.lastname: Kharashi
authors.forename: Mohanna Al
authors.initials: MA
authors.lastname: Jindan
authors.forename: Radhika
authors.initials: R
authors.lastname: Tandon
authors.forename: Jeena
authors.initials: J
authors.lastname: Mascarenhas
authors.forename: Boris
authors.initials: B
authors.lastname: Malyugin
authors.forename: Ma Dominga B
authors.initials: MD
authors.lastname: Padilla
authors.forename: Quresh
authors.initials: Q
authors.lastname: Maskati
authors.forename: Nisheeta
authors.initials: N
authors.lastname: Agarwala
authors.forename: Johan
authors.initials: J
authors.lastname: Hutauruk
authors.forename: Manoj
authors.initials: M
authors.lastname: Sharma
authors.forename: Fei
authors.initials: F
authors.lastname: Yu
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001187:Artificial Organs; D001208:Asia; D002057:Burns, Chemical / Q000503:physiopathology / Q000601:surgery*; D002648:Child; D002675:Child, Preschool; D003315:Cornea; D005126:Eye Burns / Q000139:chemically induced* / Q000503:physiopathology; D005260:Female; D006084:Graft Rejection / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D015994:Incidence; D038622:Internationality; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications; D019736:Prostheses and Implants; D019919:Prosthesis Implantation; D012008:Recurrence; D012189:Retrospective Studies; D014792:Visual Acuity / Q000502:physiology; D055815:Young Adult