International results with the Boston type I keratoprosthesis.

PURPOSE: 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. DESIGN: Retrospective review of consecutive clinical case series. PARTICIPANTS: 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. MAIN OUTCOME MEASURES: 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.

The Asia Cornea Society Infectious Keratitis Study: A Prospective Multicenter Study of Infectious Keratitis in Asia.

PURPOSE: To survey the demographics, risk factors, microbiology, and outcomes for infectious keratitis in Asia. DESIGN: Prospective, nonrandomized clinical study. METHODS: Thirteen study centers and 30 sub-centers recruited consecutive subjects over 12-18 months, and performed standardized data collection. A microbiological protocol standardized the processing and reporting of all isolates. Treatment of the infectious keratitis was decided by the managing ophthalmologist. Subjects were observed for up to 6 months. Main outcome measures were final visual acuity and the need for surgery during infection. RESULTS: A total of 6626 eyes of 6563 subjects were studied. The majority of subjects were male (n = 3992). Trauma (n = 2279, 34.7%) and contact lens wear (n = 704, 10.7%) were the commonest risk factors. Overall, bacterial keratitis was diagnosed in 2521 eyes (38.0%) and fungal keratitis in 2166 eyes (32.7%). Of the 2831 microorganisms isolated, the most common were Fusarium species (n = 518, 18.3%), Pseudomonas aeruginosa (n = 302, 10.7%), and Aspergillus flavus (n = 236, 8.3%). Cornea transplantation was performed in 628 eyes to manage ongoing infection, but 289 grafts (46%) had failed by the end of the study. Moderate visual impairment (Snellen vision less than 20/60) was documented in 3478 eyes (53.6%). CONCLUSION: Demographic and risk factors for infection vary by country, but infections occur predominantly in male subjects and are frequently related to trauma. Overall, a similar percentage of bacterial and fungal infections were diagnosed in this study. Visual recovery after infectious keratitis is guarded, and corneal transplantation for active infection is associated with a high failure rate.

International Outcomes of the Boston Type I Keratoprosthesis in Stevens-Johnson Syndrome.

PURPOSE: To determine the factors influencing outcomes of Boston type I keratoprosthesis implantation in Stevens-Johnson syndrome (SJS) and to compare the results with those of individuals without SJS. METHODS: This is a multicenter, retrospective, comparative consecutive case series of patients undergoing keratoprosthesis implantation in Los Angeles, Kolkata, and Manila. Statistical analysis was performed to identify significant differences in visual acuity, complications, and retention between SJS and non-SJS populations. RESULTS: A total of 234 keratoprosthesis procedures were performed in 209 eyes, including 40 performed in 27 eyes of 26 patients with SJS. Procedures in patients with SJS were more frequently performed as repeat keratoprostheses (33% vs. 8%, P < 0.001) but less frequently in eyes with glaucoma (26% vs. 71%, P < 0.001) or multiple previous keratoplasties (15% vs. 59%, P < 0.001). A significantly greater percentage of individuals with SJS had a corrected distance visual acuity ≥20/200 12 months after surgery compared with individuals without SJS (100% vs. 67%, P = 0.002). Several postoperative complications were more common in SJS, including corneal stromal necrosis (59% vs. 8%, P < 0.001), corneal infiltrates (30% vs. 10%, P = 0.009), and persistent corneal epithelial defects (59% vs. 24% P < 0.001), which led to a higher retention failure rate (0.306/eye-year vs. 0.068/eye-year, P < 0.001) and secondary surgical procedures. However, after repeat implantation, eyes with SJS were no less likely to ultimately retain a keratoprosthesis (82% vs. 89%, P = 0.34). CONCLUSIONS: The Boston type I keratoprosthesis is an effective means to restore vision in individuals with SJS. Although retention failure and several postoperative complications are more common in SJS, sight-threatening complications such as endophthalmitis and retinal detachment are not.

Corneal endothelial cell density and morphology in normal Filipino eyes.

OBJECTIVE: To describe the corneal endothelial cell density and morphology in normal adult Filipino eyes. METHODS: Specular microscopy was performed in 640 eyes of 320 normal Filipino volunteers aged 20 to 86 years. Of these, 163 were male, and 157 were female. Mean cell density (MCD), mean cell area (MCA), coefficient of variation (CV) in cell size (polymegathism), and hexagonality were recorded and analyzed in relation to fellow eyes, gender, and age. RESULTS: MCD was 2798 +/- 307.2 cells/mm, and MCA was 363.0 +/- 40.3 microm. Results showed that women had a MCD 7.8% greater than men (P < 0.01). Regression analysis showed a consistent decrease in MCD (r = -0.47) and increase in MCA (r = 0.45) from 20 to 60 years of age. This was followed by a marked decrease in correlation and apparent trend reversal for both variables in the groups above 60 years (MCD r = 0.18, MCA r = -0.04) accompanied by a marked increase in CV in cell size (20-60 years r = -0.04, >60 years r = 0.33). A very low negative correlation (r = -0.10) was noted between hexagonality and increasing age through all age groups. CONCLUSION: The first normative data for the endothelium of Filipino eyes are reported. There are statistically significant differences in MCD between genders, and a consistent decrease in MCD and increase in MCA with age only until 60 years old, after which correlation between age and these variables decreases. Polymegathism and correlation between CV in cell size and age markedly increase after age 60.