title: High and Low Contrast Visual Acuity Are Not Affected in Amyotrophic Lateral Sclerosis.
abstract: The afferent visual system may be affected by neuro-degeneration in amyotrophic lateral sclerosis (ALS) based on observations of visual function impairment and retinal inclusions on histopathology in ALS patients. To test the hypothesis that visual acuity is impaired in ALS, we compared three measures of visual acuity in ALS patients (n = 25) attending a multidisciplinary ALS clinic and age matched control subjects (n = 25). Bilateral monocular and binocular visual acuities were assessed using high contrast (black letters on white background) and low contrast (2.5%, 1.25% grey letters on white background) visual acuity charts under controlled lighting conditions following refraction. Binocular summation was calculated as the difference between binocular and best monocular acuity scores. There were no associations between binocular or monocular high contrast visual acuity or low contrast visual acuity and amyotrophic lateral sclerosis diagnosis (generalized estimating equation models accounting for age). Binocular summation was similar in both amyotrophic lateral sclerosis and control subjects. There was a small magnitude association between increased duration of ALS symptoms and reduced 1.25% low contrast visual acuity. This study does not confirm prior observations of impaired visual acuity in patients with amyotrophic lateral sclerosis and does not support this particular measure of visual function for use in broad scale assessment of visual pathway involvement in ALS patients.
authors.affiliation: Department of Ophthalmology and Visual Sciences, Division of Neuro-ophthalmology, University of Illinois at Chicago, Chicago, Illinois, United States of America.|Department of Neurology and Rehabilitation, University of Illinois at Chicago, Chicago, Illinois, United States of America.
authors.forename: Heather E
authors.identifier: http://orcid.org/0000-0003-4373-447X
authors.initials: HE
authors.lastname: Moss
authors.affiliation: Department of Ophthalmology and Visual Sciences, Division of Neuro-ophthalmology, University of Illinois at Chicago, Chicago, Illinois, United States of America.
authors.forename: Monica
authors.initials: M
authors.lastname: Samelson
authors.affiliation: Department of Ophthalmology and Visual Sciences, Division of Neuro-ophthalmology, University of Illinois at Chicago, Chicago, Illinois, United States of America.
authors.forename: Girish
authors.initials: G
authors.lastname: Mohan
authors.affiliation: Department of Neurology and Rehabilitation, University of Illinois at Chicago, Chicago, Illinois, United States of America.
authors.forename: Qin Li
authors.initials: QL
authors.lastname: Jiang
mesh_terms: D000328:Adult; D000368:Aged; D000690:Amyotrophic Lateral Sclerosis / Q000503:physiopathology*; D016022:Case-Control Studies; D015350:Contrast Sensitivity; D003430:Cross-Sectional Studies; D006801:Humans; D008875:Middle Aged