Several studies have pointed out that a potential side effect of laser eye surgery is post-operative glare.
Researchers in Belgium have found just the opposite: LASEK eye surgery appears to reduce pre-operative retinal straylight, which is a potential source of glare. The results of their study suggests patients undergoing LASEK for the correction of myopia may have reduced glare after surgery, especially if they wore soft contact lenses prior to the procedure.
Retinal straylight is light that is scattered by defects in the optical media of the eye and therefore is not available to be focused into a clear image by the retina. This scattered light reduces the contrast of images created by the retina and contributes to glare.
To quantify the changes in retinal straylight after LASEK eye surgery, researchers at Antwerp University Hospital (Edegem, Belgium) evaluated straylight values of 86 eyes of 49 patients scheduled for LASEK surgery.
Straylight measurements were taken prior to LASEK surgery and 6 months after the procedure, using a device called the Oculus C-Quant straylight meter (Oculus Optikgeräte GmbH, Wetzlar, Germany).
Straylight values also were compared with values in a “normal” reference database.
Patients were divided into four groups, based on their habitual method of vision correction prior to surgery:
- Rigid contact lenses
- Soft contact lenses
- Spectacles after a period of contact lens wear
- Spectacles only
Analysis of the pre-operative data revealed that age-corrected straylight values were significantly elevated among patients in the study, especially if they wore soft contact lenses full-time prior to LASEK surgery.
Six months after LASEK, straylight values for all patient groups had returned to normal levels, regardless of the amount of nearsightedness and method of vision correction prior to surgery.
The researchers concluded that higher-than-normal retinal straylight values normalized after LASEK refractive surgery among this patient population.
They also said that wearing soft contact lenses causes higher pre-operative retinal straylight, which is eliminated after LASEK.
SOURCE: Straylight before and after LASEK in myopia: Changes in retinal straylight. Investigative Ophthalmology & Visual Science. Published online ahead of print December 10, 2009.
Tags: complications, glare, side-effects