heterophoria /het·ero·pho·ria/ (-for´e-ah) failure of the visual axes to remain parallel after elimination of visual fusional stimuli.heterophor´ic
het·er·o·pho·ri·a (h t  -r -fôr  -)n. A tendency of the eyes to deviate from the parallel. |
heterophoria
latent strabismus.
heterophoria
The tendency for the two visual axes of the eyes not to be directed towards the point of fixation, in the absence of an adequate stimulus to fusion. Thus, the active and passive positions do not coincide for that particular fixation distance. This tendency is characterized by a deviation that can take various forms according to its relative direction such as esophoria, exophoria, excyclophoria, incyclophoria, hyperphoria, hypophoria. Syn. phoria. See anisophoria; dextrophoria; dissociation; kataphoria; laevophoria.
associated heterophoria A term sometimes used to denote the prism power necessary to align the nonius markers of a fixation disparity test. It is not strictly speaking a heterophoria because only part of the visual field is dissociated while the rest of the field is fused (that fused area is often referred to as fusion lock or binocular lock). The dissociation of only part of the field is achieved by using either a method of cross-polarization (e.g. Mallet fixation disparity unit) or a septum (e.g. Turville infinity balance test). Syn. aligning prism; compensating prism. See retinal disparity; Disparometer; Mallett fixation disparity unit; Turville infinity balance test.
compensated heterophoria Any heterophoria that does not give rise to symptoms or to suppression.
decompensated d. See uncompensated heterophoria.
dissociated heterophoria Any heterophoria which is revealed by methods which produce complete dissociation such as the cover test, the Maddox rod test, the Thorington test, the von Graefe's test, the diplopia test, etc.
uncompensated heterophoria Any heterophoria which gives rise to symptoms or to suppression. The symptoms are associated with visual tasks, especially close work, but also occasionally, inadequate illumination. Resting the eyes will usually lessen the symptoms. Unbalanced spectacle correction, deterioration in the patient's general health, worry and anxiety can also sometimes give rise to an uncompensated heterophoria. This type of heterophoria is presumed to manifest itself as fixation disparity. Syn. decompensated heterophoria. See Disparometer; Mallett fixation disparity unit; relieving prism.
associated heterophoria A term sometimes used to denote the prism power necessary to align the nonius markers of a fixation disparity test. It is not strictly speaking a heterophoria because only part of the visual field is dissociated while the rest of the field is fused (that fused area is often referred to as fusion lock or binocular lock). The dissociation of only part of the field is achieved by using either a method of cross-polarization (e.g. Mallet fixation disparity unit) or a septum (e.g. Turville infinity balance test). Syn. aligning prism; compensating prism. See retinal disparity; Disparometer; Mallett fixation disparity unit; Turville infinity balance test.
compensated heterophoria Any heterophoria that does not give rise to symptoms or to suppression.
decompensated d. See uncompensated heterophoria.
dissociated heterophoria Any heterophoria which is revealed by methods which produce complete dissociation such as the cover test, the Maddox rod test, the Thorington test, the von Graefe's test, the diplopia test, etc.
uncompensated heterophoria Any heterophoria which gives rise to symptoms or to suppression. The symptoms are associated with visual tasks, especially close work, but also occasionally, inadequate illumination. Resting the eyes will usually lessen the symptoms. Unbalanced spectacle correction, deterioration in the patient's general health, worry and anxiety can also sometimes give rise to an uncompensated heterophoria. This type of heterophoria is presumed to manifest itself as fixation disparity. Syn. decompensated heterophoria. See Disparometer; Mallett fixation disparity unit; relieving prism.
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