Two types of laser surgery — photorefractive keratectomy and laser in situ keratomileusis — are currently used to correct refractive errors such as nearsightedness. However, little is known about how these procedures affect the cornea, the transparent membrane covering the eye, on the cellular level over the long term, according to the release.
Sanjay V. Patel, MD, and William M. Bourne, MD, studied 29 eyes of 16 patients who had undergone LASIK or PRK. Photographs of the cells lining the cornea (endothelial cells) were taken and analyzed before and nine years after surgery. The annual rate of corneal endothelial cell loss in the eyes of patients who had had surgery was compared with those of 42 eyes that had not undergone either procedure.
Nine years after surgery, the density of cells lining the cornea had decreased by 5.3 percent from their preoperative state. However, the average annual rate of cell loss (0.6 percent) was the same in corneas of eyes that were operated on and those that were not.
The results support numerous short-term studies that found no significant endothelial cell loss after LASIK and PRK.
Read the JAMA/Archives release on the long-term effects of laser surgery on corneal cells.
