A preliminary investigation into the aetiology of Meares-Irlen syndrome.
A recent double-masked placebo-controlled trial has confirmed that some children experience a reduction in symptoms of eyestrain and headache when they read through individually prescribed coloured filters and has shown that this benefit cannot be solely attributed to a placebo effect. People who are helped by coloured filters in this way have been described as having "Meares-Irlen syndrome'. We investigated the mechanism of this benefit by studying the optometric and visual perceptual characteristics of the children in the double-masked study. This population had normal refractive errors and heterophorias (none of the subjects had strabismus). They demonstrated slightly, but significantly, reduced amplitudes of accommodation and vergence and poor stereo-acuity. However, these factors seemed to be correlates of Meares-Irlen syndrome rather than the underlying cause. Pattern glare, a sensitivity to striped patterns (e.g. lines of text), was prevalent in our sample and was significantly associated with the subjects' symptoms. The spatial contrast sensitivity function was normal.
Evans
B J
BJ
Institute of Optometry, London, UK.
Wilkins
A J
AJ
Brown
J
J
Busby
A
A
Wingfield
A
A
Jeanes
R
R
Bald
J
J
D000293:Adolescent; D001248:Asthenopia / Q000517:prevention & control*; D002648:Child; D003116:Color; D004311:Double-Blind Method; D004410:Dyslexia / Q000503:physiopathology; D005133:Eye Movements; D005260:Female; D005374:Filtration; D006261:Headache / Q000517:prevention & control; D006801:Humans; D008297:Male; D010364:Pattern Recognition, Visual / Q000502:physiology; D010469:Perceptual Distortion; D011601:Psychophysics; D011932:Reading; D012030:Refractive Errors / Q000503:physiopathology; D015348:Vision, Binocular; D014792:Visual Acuity