Excimer Laser Phototherapeutic Keratectomy

The objective of this study was to evaluate the safety and efficacy of excimer laser phototherapeutic keratectomy in the treatment of anterior corneal pathology in a group of 45 patients. Forty-five patients were treated with the Visx Excimer Laser System for various types of anterior corneal pathology including postinflammatory and postsurgical scars, stromal dystrophies, surface degenerations, pterygia, and epithelial basement membrane dystrophies. Excimer laser phototherapeutic keratectomy (PTK) has been used to treat anteriorly located corneal pathology since 1990; however, most published studies thus far have been composed of small numbers of patients with limited duration of follow-up. The present study is one of the largest domestic PTK series with one of the longest mean follow-ups. Forty patients were followed for > or = 6 months with a mean follow-up of just less than 1 year (11.25 months). Statistically significant improvement was achieved in irritative symptoms and visual acuity. Best spectacle corrected visual acuity (BSCVA) improved a mean of two lines (range, -3 to +7) with 20/50 or better BSCVA present in 29% of patients preoperatively improving to 60% postoperatively. Refractive changes were unpredictable. Mean spherical equivalent underwent a hyperopic shift of 2.81 diopters (D). Fifty percent of patients developed > or = 1 D of refractive astigmatism. Complications occurred in six patients with loss of BSCVA, three patients with topical corticosteroid associated increased intraocular pressure, and three patients with recurrent herpes simplex stromal keratouveitis. Excimer laser phototherapeutic keratectomy can consistently achieve a modest to a more substantial improvement in irritative ocular symptoms and/or visual acuity with significant potential for adverse results that appear to be less severe than the complications associated with alternative treatment by keratoplasty.