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Subjective symptoms of ocular fatigue, discomfort, lacrimation, and headaches arising from use of the eyes.
[G. astheneia, weakness, + ōps, eye]
eyestrain/eye·strain/ (-strān) fatigue of the eye from overuse or from uncorrected defect in focus of the eye.
Pain and fatigue of the eyes, often accompanied by headache, resulting from prolonged use of the eyes, uncorrected defects of vision, or an imbalance of the eye muscles.
Term used to describe any symptoms associated with the use of the eyes. The causes of asthenopia are numerous: sustained near vision, either when the accommodation amplitude is low or hypermetropia is uncorrected (accommodative asthenopia), aniseikonia (aniseikonic a.), astigmatism (astigmatic a.), pain in the eye (asthenopia dolens), heterophoria (heterophoric a.), ocular inflammation (asthenopia irritans), hysteria (nervous a.), uncorrected presbyopia (presbyopic a.), improper illumination (photogenous a.) or retinal disease (retinal a.). Syn. eyestrain; near point stress (NPS) (although this term is restricted to any symptoms arising from near vision). See convergence excess; convergence insufficiency; divergence insufficiency; visual fatigue; ocular headache.