Abstract
Abstract: :
Purpose: Over the past decade, the use of the Dohlman–Donne Keratoprosthesis (artificial cornea) Type I (KPro I) has become increasingly popular. This prosthesis is well tolerated and can restore long–term visual functional to an otherwise blind eye. Here we report a retrospective analysis on 80 patients from 15 US sites in an effort to determine pre–operative predictors of visual outcome. Methods: A multicentered, retrospective, interventional case series review of patients receiving the KPro I between January 2003 and November 2004. All best corrected Snellen visual acuity (BCVA) measurements were converted to the logMAR scale for analyses. Multiple regression analyses of post–operative BCVA versus pre–operative patient characteristics (age, IOP, prior number of corneal transplants, BCVA) at various time points were performed. Underlying diagnoses were grouped according to similar pathophysiologic mechanism and their impact upon visual outcome was examined. In addition, the impact of comorbid glaucoma and glaucoma surgery was examined. Results: The average patient was ∼64 years old with an IOP of 15 mmHg and a history of 2 to 3 prior transplantation surgeries. Average post–op BCVA was 20/100 (n=32), 20/56 (n=27), and 20/78 (n=29) at 1, 6, and 12–months respectively, up from an average pre–operative BCVA in the counting fingers range. Patient age, pre–operative IOP, and number of previous corneal transplants were not related to visual outcome at any time point measured (1, 6, 12 months). A greater improvement in vision from baseline was observed in patients with poorer pre–operative BCVA at 1 (n=32, p<0.001), 6 (n=27, p<0.001) and 12 months (n=29, p=0.066). On average, each diagnostic group benefited from the KPro I and a history of ocular HSV did not prevent a good visual outcome. Conclusions: Although these preliminary results stem from a small database, they suggest that practitioners should consider KPro implantation irregardless of age, pre–op IOP, or the number of previous failed grafts. This review supports prior work demonstrating enduring visual restoration for many patients to at least 1 year. A history of ocular HSV does not appear to affect the success of the procedure within the first year following surgery. Further prospective research into KPro I implantation is warranted.
Keywords: keratoprostheses • cornea: clinical science