Page 46 - The UK Guide to Laser Eye Surgery
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46 Questions about technology
 Wavefront aberrometry
What is it for?
Measuring the optical imperfections of your eye that are not correctable with glasses alone (these are known as the ‘higher order aberrations’ in your visual system). These irregularities of your cornea and optical system affect the finer quality aspects of your vision (beyond the normal refractive errors of short-sightedness, long- sightedness, presbyopia and astigmatism).
A wavefront aberrometer records data from the light passing through your eye’s optical system (the lens and cornea).
A map of the imperfections in your eye is then produced, as well as a visual system analysis.
Different aberrometers measure different resolution with the number of spots (measurement points) ranging from as low as 60 to as high as 902. A low resolution aberrometer is like a watercolour painting. It provides a general impression of the landscape, measuring just a few points
and using a mathematical formula to work out an approximate image of the rest. A high resolution aberrometer is more like a photograph – it records much more data, giving a more accurate map of the number and location of imperfections. This means the surgeon can plan your treatment precisely to incorporate these irregularities.
What actually happens?
You rest your chin on a padded support and stare straight into the examining instrument. The clinician sits in front of you and aligns the instrument by having you focus on a visual target. You will be asked to open your eyes widely. The clinician
will then take one or more readings of the ‘wavefront’ of each eye.
How does it feel?
You feel nothing as the instrument does not make contact with your eye.
How does it benefit you?
The information mapped by a wavefront aberrometer can be fed into the laser to achieve better results. Using wavefront aberrometry allows your surgeon to decide if you would likely benefit from
a ‘wavefront guided’ laser eye surgery treatment (which aims to improve on the optical imperfections of your eye, beyond what glasses alone can correct). Wavefront technology can also detect certain eye conditions that would preclude you from getting an optimal laser eye surgery result.
                  


















































































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