An Introduction to Higher Order Aberrations

by Marin Nagelberg, OD and Helene Pippin, OD

Higher order aberrations (HOAs) are subtle optical imperfections that can cause symptoms of blurred vision, halos, glare, and shadowing. HOAs are not to be confused with lower order aberrations like nearsightedness (myopia), farsightedness (hyperopia), or regular astigmatism which can be corrected with glasses or standard contact lenses. Higher order aberrations typically result from irregularities in the parts of the eye responsible for light focusing on the back of the eye (the retina). Conditions causing an irregular cornea, like keratoconus, corneal scarring, trauma, and other diseases, as well as changes to the crystalline lens of the eye, can cause HOAs.

Symptoms caused by HOAs cannot be easily corrected with standard eyeglasses or contact lenses. Common symptoms one may experience from higher order aberrations are contrast issues, glare, halos, shadowing or ghost images, and smeared eyesight.

Scleral contact lenses are a safe and effective option for correcting higher order aberrations. Due to the stability of scleral lenses on the eye, specialized optics can be placed onto the lens to correct HOAs. This is achieved using wavefront guided technology that maps each individual eye’s aberration profile. The profile is used to build a custom optical design that is placed onto the contact lens and counteracts the aberrations. This typically results in improved visual acuity, reduced glare and halos, reduced shadowing, and enhanced contrast. Ask your eye doctor if you may benefit from HOA correction in your scleral lens.