How Laser Eye Surgery Affects Contrast Sensitivity
Contrast sensitivity is the eye’s ability to perceive the difference between an object and its background. It is often referred to as the crispness of your vision. If you complain of poor vision in certain conditions, even though your ‘normal’ (black on white) vision is good, this may be an indication that you have reduced contrast sensitivity.
In low light, poor contrast sensitivity can affect your ability to perform certain tasks and clearly see objects which are not well defined from their background (for example a light grey object on a white surface). Contrast sensitivity deteriorates with age and can also be reduced by some eye conditions, such as diabetic retinopathy and cataracts. In some cases, Laser Eye Surgery can also temporarily reduce your contrast sensitivity – although the reduction is often minimal.
At London Vision Clinic, we use the latest laser technology, allowing us to perform extremely precise treatments and to preserve contrast sensitivity. For example, studies have demonstrated the preservation of both the quality of vision (contrast sensitivity) and stereoacuity (the ability to see in 3D) with PRESBYOND® Laser Blended Vision. This is in contrast to other ways of treating presbyopia (such as multi-focal contact lenses) which are known to decrease contrast sensitivity in many patients.
We also spend a long time conducting pre-operative tests, including extensive contrast-sensitivity testing. Measuring your contrast sensitivity provides your surgeon with another measure of how well you already see at night, giving him an indication of how to best plan your treatment in order to avoid symptoms such as night vision disturbances following Laser Eye Surgery.
Our advanced technology, such as lasers with aspheric treatment profiles, aims to preserve contrast sensitivity. Not all aspheric treatment profiles are alike, but in general lasers using these will be safer with respect to night vision. Some systems are so well designed that they can even improve your contrast sensitivity and night vision.
If you have any questions about contrast sensitivity, or about other aspects of Laser Eye Surgery, please call us on 020 7224 1005, or contact us for more information.