Pupil size irrelevant to post-LASIK complaints

THOROFARE, N.J. — Pupil size has a smaller influence on patient complaints after LASIK surgery than previously thought, said Steven C. Schallhorn, MD. Logically, “patients should have more quality of vision symptoms if their low light pupil size is larger than the optical zone after LASIK,” Dr. Schallhorn said. However, his study did not find an influence at the 6 month follow-up in eyes treated with a 6-mm optical zone.

Dr. Schallhorn and colleagues studied a consecutive series of 100 patients undergoing LASIK. Average preoperative myopia was -5 D, and a 6-mm ablation zone was used. Patients were evaluated preoperatively, intraoperatively and at 1, 3 and 6 months postoperatively.

About 80% of the patients achieved a postop uncorrected visual acuity (UCVA) of 20/20, and 98% achieved a UCVA of 20/40. At the 1 month follow-up, mean scores in the treated eye were significantly elevated for glare, haze and halos. At the 3 month follow-up, scores were elevated only for halos. At 6 months postop, mean scores had returned to preop levels, Dr. Schallhorn said.

Few of the variables looked at were significant in regression analysis, Dr. Schallhorn said. One significant term was the UCVA result, however, which was highly correlated with postop patient complaints. He did add that the “higher the preop manifest spherical equivalent (MSE), the greater the level of complaint. But there was no relationship between complaints and postop contrast acuity.”

An association does exist between glare score and preop MSE. “Patients who have higher levels of preop myopia tend to have more complaints,” Dr. Schallhorn said.

More details about Dr. Schallhorn's study can be found in the March 15 print edition of Ocular Surgery News.