Surgeons link nerve recovery to decrease in anterior keratocyte density after LASIK

Sub-basal nerve fiber density shows a gradual yet incomplete recovery that may be associated with a reduction in the density of the most anteriorly located keratocytes more than 2 years after LASIK, a prospective study found.

J. A. O. Moilanen, MD, and colleagues evaluated the 2-year effects of myopic LASIK on corneal thickness, keratocyte density and nerve recovery among 15 eyes of 15 patients with an average refractive error of –10.1 D at baseline. The investigators obtained visual acuity, refraction, biomicroscopy and in vivo confocal microscopy measurements for each patient at 1 and 5 days, 2 weeks, 1, 3 and 6 months and 2 years postoperatively.

At 2 years, all patients had achieved a best corrected visual acuity of 20/20, and nine patients had progressed to within ±0.5 D of intended correction.

Although the total corneal thickness had not changed, epithelial hyperplasia persisted for the duration of follow-up, investigators found.

The density of keratocytes in the anterior stroma and posterior to the flap decreased slightly over follow-up; however, the investigators observed no such reductions in mid-stromal or posterior keratocytes.

Although sub-basal nerve density had decreased 82% at 5-day postop, nerve density was only 64% of the preoperative value at 2 years, according to the study, published in the October issue of British Journal of Ophthalmology.