Nonaccommodative convergence excess.

G K von Noorden; C W Avilla

doi:10.1016/0002-9394(86)90466-6

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Nonaccommodative convergence excess.

G K von Noorden·C W Avilla

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Abstract

Nonaccommodative convergence excess is a condition in which a patient has orthotropia or a small-angle esophoria or esotropia at distance and a large-angle esotropia at near, not significantly reduced by the addition of spherical plus lenses. The AC/A ratio, determined with the gradient method, is normal or subnormal. Tonic convergence is suspected of causing the convergence excess in these patients. Nonaccommodative convergence excess must be distinguished from esotropia with a high AC/A ratio and from hypoaccommodative esotropia. In 24 patients treated with recession of both medial recti muscles with and without posterior fixation or by posterior fixation alone, the mean correction of esotropia was 7.4 prism diopters at distance and 17 prism diopters at near.

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Accommodation, Ocular Adolescent Adult Analysis of Variance Child Child, Preschool Convergence, Ocular Eye Movements Eyeglasses Fixation, Ocular Humans Infant Infant, Newborn Vision Disorders Visual Acuity Comparative Study Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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G K von Noorden, C W Avilla. 1986-01-15. Nonaccommodative convergence excess.. https://doi.org/10.1016/0002-9394(86)90466-6

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