EXCIMER-LASER KERATECTOMY FOR ASTIGMATISM OCCURRING AFTER PENETRATINGKERATOPLASTY

Purpose: To review the results of photorefractive keratectomy used to treat astigmatism occurring after penetrating keratoplasty. Methods: S even patients who had undergone corneal transplantation previously and had significant postoperative astigmatism were included. All these pa tients were intolerant of spectacle and contact lens correction. Excim er laser keratectomy was performed to reduce the astigmatic error. Min imum follow-up of 12 months was necessary for study inclusion. Results : The average refractive cylinder decreased from 5.32 diopters (D) pre operatively to 2.79 D postoperatively. The refractive cylinder was red uced in six of the seven eyes attempted. The average preoperative kera tometric cylinder decreased from 5.54 D (range, 1.50-10.00 D) to 4.00 D (range, 1.00-7.50 D) postoperatively. The best spectacle-corrected v isual acuity was unchanged (within 1 line) in three eyes, improved in two, and decreased in two. The complications included a loss of at lea st two lines in spectacle-corrected visual acuity in two eyes and scar ring in one. Conclusions: Excimer laser keratectomy can reduce the ast igmatism after penetrating keratoplasty. The excellent results in some eyes offer promise for this technique in the future.