What happens during the wavefront measurement?

Your ophthalmologist will map both of your eyes using a wavefront scanner, called an analyzer or aberrometer. This device produces a very precise, detailed map of light rays as they travel through your eye, highlighting imperfections in your vision.
With your chin on the chin rest of the aberrometer, you will be asked to stare past what is called a target light. To ensure correct measurement, be sure to stare past the target light, not directly at it. Your eye’s focus should be as relaxed as possible.
A targeted beam of light will be sent through your eye and focused on the retina. As the wave of light rays is reflected back from the retina through the eye’s vitreous, lens, pupil and cornea, a sensor will measure the irregularities in the wavefront pattern of light as it emerges from your eye.
A wavefront map of an eye with visual imperfections (aberrations) appears curved or distorted because some light rays reach the retina before others or strike different points on the retina. A wavefront diagram showing such distortions may look like anything
from a potato chip to an egg crate. In contrast, the wavefront map of an eye with no visual errors would show a flat surface, because all of the light rays would travel evenly through the eye.
Using measurements, the wavefront computer will create an accurate, three-dimensional map of your eye’s visual system, including specific imperfections in the cornea. This wavefront data will be used to program the excimer laser, allowing your ophthal- mologist to customize the reshaping of your cornea.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.