THOROFARE, N.J., April 2007 — People who develop unusual vision symptoms following LASIK are more likely to be diagnosed with higher-order aberrations after a procedure, according to study results published in the March issue of Journal of Refractive Surgery.

Investigators from different study sites say blurred vision was the most common type of unexpected vision symptom associated with LASIK. Other unusual symptoms included double vision, halos, and vision fluctuation.

People experiencing these types of symptoms following LASIK also were diagnosed with significantly lower visual acuity and contrast sensitivity.

Higher-order aberrations are more complex vision errors than lower-order aberrations, which have more familiar names such as nearsightedness, farsightedness and astigmatism.

Higher-order aberrations are identified by the types of distortions acquired by a wavefront of light as it passes through your eye.  They have relatively unfamiliar names such as coma, spherical aberration, and trefoil. These types of aberrations can produce vision errors such as difficulty seeing at night, glare, halos, blurring, starburst patterns, or double vision.

 No eye is perfect, which means that all eyes have at least some degree of higher-order aberrations. If you are diagnosed with higher-order aberrations, you need not be concerned unless they are significant enough to cause vision symptoms.

Significant amounts of aberrations can pose vision problems because they interfere with the eye's ability to see clear and distinct images.