Higher Order Aberrations and LASIK

The phrase "high-order aberrations" is commonly associated with LASIK surgery, as many LASIK providers promote the theory that it is necessary to correct these aberrations to enhance the surgery. Despite the fact that this theory has failed, some doctors use it to encourage patients to undergo unnecessary treatments for higher-order aberrations. Below is an overview of higher-order aberrations.

What are Higher-Order Aberrations?
As light rays ass through the individual optical components of the eye, they are distorted by imperfections in the cornea and lens. The majority of people experience minor or "low level" aberrations such as nearsightedness, farsightedness, and astigmatism.

However, patients with severe distortions, called "higher-order aberrations", experience more pronounced symptoms, including double vision, excessive blurriness, halos, and especially poor night vision.
 
Theories about Higher-Order Aberrations
Since LASIK surgery primarily targets lower-order aberrations, some doctors theorize that it is necessary to treat higher-order aberrations with other treatments in order to maximize LASIK results. Many of these surgeons depend heavily on Wavefront™ analyses (also used in CustomVue™ and Custom LASIK) of a patient's higher-order aberrations, believing that Wavefront™ provides a detailed diagnosis of the aberration.  

The Truth about Higher-Order Aberrations and LASIK Surgery
While theoretically sound, the Wavefront™ approach has failed. While higher-order aberrations can affect a person's vision, they do not have a tremendous effect on successful LASIK surgery. This is due to the effect of surgery and the aging process on these types of aberrations. The truth is:
•    Cutting of the corneal flap alters the higher-order aberration
•    Higher-order aberrations change significantly as a person ages
•    The healing process changes the higher-order aberration
•    Refractive surgeries do not have the submicron precision necessary to correct higher-order aberrations
•    There is no consensus on the benefit to the patient of treating higher-order aberrations