LASEK, LASIK reduce corneal sensitivity, induce nerve abnormalities

Corneal sensitivity and subbasal nerve morphology can be negatively affected by both LASEK and LASIK, according to a study by researchers in the United Kingdom. Corneal sensitivity recovered at 3 months postop, but subbasal nerves remained abnormal at 6 months follow-up, the authors noted.

Taym Darwish, MD, MSc, PhD, and colleagues evaluated the recovery of the corneal subbasal nerve plexus and corneal sensitivity in 30 myopic patients treated with LASEK and 20 myopic patients treated with LASIK.

Investigators found that central corneal sensitivity had significantly decreased at 1 month postop in both patient groups, but it returned to normal by 3 months follow-up, according to the study.

Among LASIK patients, corneal subbasal nerve fiber density, nerve branch density, nerve fiber length and nerve fiber width all had decreased significantly at 1 month postop and had not returned to preoperative levels at 6 months follow-up.

In addition, nerve fiber tortuosity had decreased significantly at 1 month postop in LASEK patients. However, it returned to preoperative levels by 3 months postop.

LASIK caused no significant changes in nerve fiber tortuosity, the authors noted.

"Despite the different forms of surgical trauma to corneal nerves with LASIK and LASEK, there was no apparent difference in the time course of recovery of corneal structure and function," the authors said.

The study is published in the September issue of Journal of Cataract and Refractive Surgery.