The human eye may be able to self-adjust and partially compensate for optical aberrations caused by LASIK eye surgery, according to a new study.
LASIK, PRK and other corneal refractive surgery have been shown to increase higher-order aberrations in the eye that can affect visual clarity. Even customized, wavefront-guided LASIK typically increases these aberrations to some extent.
Researchers in France, however, have found that within 3 months after LASIK surgery, the human eye appears to be able to compensate to some degree for aberrations in the cornea caused by LASIK, thereby reducing the total aberrations of the eye.
The investigators studied 57 eyes of 57 patients who underwent conventional LASIK surgery for the correction of myopia. All eyes were measured before and 3 months after surgery to compare corneal aberrations and total eye aberrations, using an OPD-Scan aberrometer (NIDEK Co Ltd.)
Measurements taken 3 months after LASIK surgery revealed that although total corneal higher-order aberrations (HOA) increased by a factor of 2.47 after LASIK, total eye HOA increased by a factor of 1.77.
For a specific type of HOA called spherical aberration, corneal spherical aberration (SA) increased by a factor of 2.64 after LASIK, while total eye SA increased by a factor of 1.46.
The lower magnitude of total eye aberrations compared with corneal aberrations after LASIK suggest some degree of compensation by the internal optics of the eye to reduce the affect of the corneal aberrations, according to the study authors.
The researchers concluded that the human eye appears to have an adaptive ability that enables it to partially compensate for corneal aberrations caused by LASIK performed for the correction of myopia.
A full report of the study appears in the May 2010 issue of Journal of Refractive Surgery.