Contrast sensitivity during provoked visual impairment in multiple sclerosis.
Many patients with multiple sclerosis have subjective visual complaints that are intensified by exercise (Uhthoff's symptom). We report a case demonstrating the utility of contrast sensitivity testing in such visual complaints. Contrast sensitivity was measured before and after exercise in a multiple sclerosis patient with Uhthoff's symptom and in two healthy control subjects. A short exercise period reduced the patient's contrast sensitivity for some target sizes, but had no effect on his visual acuity; a longer exercise period produced a greater, more uniform loss of contrast sensitivity and also reduced visual acuity. Contrast sensitivities and visual acuities of the control subjects were not affected by exercise.
D000328:Adult; D005556:Form Perception / Q000502:physiology*; D006801:Humans; D008297:Male; D009103:Multiple Sclerosis / Q000503:physiopathology*; D005082:Physical Exertion; D013997:Time Factors; D014792:Visual Acuity