Biomaterial Database

A quantitative analysis of eye movements during the cover test--a preliminary report. 1995

N A Barnard, and W D Thomson

Department of Optometry and Visual Science, London, UK.

The aim of this study was to carry out quantitative analyses of eye movements during the cover test on a group (n = 57) of asymptomatic emmetropes. Eye movements were recorded during an automated cover test while subjects fixated a distance (3.4 m) and near (0.4 m) target. There was a significant difference between the amplitude of phoria measured after 2 s of occlusion compared to 10 s (P < 0.01). The mean phoria after 10 s of occlusion was 0.1 degree (eso) for distance fixation and 1.6 degrees (exo) for near fixation. The distribution was approximately normal for both distance and near fixation but the standard deviation was greater for near (2.0 degrees) than distance fixation (1.4 degrees). The pattern of eye movements during the recovery phase was more complex than is often assumed, in many cases consisting of a variety of saccadic and vergence movements involving both the covered and 'fixing' eye. The latency of the first recovery movement was significantly shorter for exophoric than esophoric deviations (P < 0.01) and the latency of some recovery movements were very short (< 150 ms).

UI	MeSH Term	Description	Entries
D003290	Convergence, Ocular	The turning inward of the lines of sight toward each other.	Convergences, Ocular,Ocular Convergence,Ocular Convergences
D004948	Esotropia	A form of ocular misalignment characterized by an excessive convergence of the visual axes, resulting in a "cross-eye" appearance. An example of this condition occurs when paralysis of the lateral rectus muscle causes an abnormal inward deviation of one eye on attempted gaze.	Esophoria,Strabismus, Convergent,Strabismus, Internal,Convergent Strabismus,Cross-Eye,Esodeviation,Intermittent Esotropia,Internal Strabismus,Monocular Esotropia,Primary Esotropia,Secondary Esotropia,Cross Eye,Cross-Eyes,Esodeviations,Esophorias,Esotropia, Intermittent,Esotropia, Monocular,Esotropia, Primary,Esotropia, Secondary,Esotropias,Intermittent Esotropias,Monocular Esotropias,Primary Esotropias,Secondary Esotropias
D005099	Exotropia	A form of ocular misalignment where the visual axes diverge inappropriately. For example, medial rectus muscle weakness may produce this condition as the affected eye will deviate laterally upon attempted forward gaze. An exotropia occurs due to the relatively unopposed force exerted on the eye by the lateral rectus muscle, which pulls the eye in an outward direction.	Exophoria,Strabismus, Divergent,Alternating Exotropia,Divergent Strabismus,Exodeviation,Monocular Exotropia,Primary Exotropia,Secondary Exotropia,Exodeviations,Exotropia, Alternating,Exotropia, Monocular,Exotropia, Primary,Exotropia, Secondary
D005133	Eye Movements	Voluntary or reflex-controlled movements of the eye.	Eye Movement,Movement, Eye,Movements, Eye
D005403	Fixation, Ocular	Positioning and accommodation of eyes that allows the image to be brought into place on the FOVEA CENTRALIS of each eye.	Focusing, Ocular,Ocular Fixation,Eye Gaze,Eye Gazes,Gaze, Eye,Gazes, Eye,Ocular Focusing
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000293	Adolescent	A person 13 to 18 years of age.	Adolescence,Youth,Adolescents,Adolescents, Female,Adolescents, Male,Teenagers,Teens,Adolescent, Female,Adolescent, Male,Female Adolescent,Female Adolescents,Male Adolescent,Male Adolescents,Teen,Teenager,Youths
D000328	Adult	A person having attained full growth or maturity. Adults are of 19 through 44 years of age. For a person between 19 and 24 years of age, YOUNG ADULT is available.	Adults
D012438	Saccades	An abrupt voluntary shift in ocular fixation from one point to another, as occurs in reading.	Pursuit, Saccadic,Saccadic Eye Movements,Eye Movement, Saccadic,Eye Movements, Saccadic,Movement, Saccadic Eye,Movements, Saccadic Eye,Pursuits, Saccadic,Saccade,Saccadic Eye Movement,Saccadic Pursuit,Saccadic Pursuits
D013285	Strabismus	Misalignment of the visual axes of the eyes. In comitant strabismus the degree of ocular misalignment does not vary with the direction of gaze. In noncomitant strabismus the degree of misalignment varies depending on direction of gaze or which eye is fixating on the target. (Miller, Walsh & Hoyt's Clinical Neuro-Ophthalmology, 4th ed, p641)	Concomitant Strabismus,Dissociated Horizontal Deviation,Dissociated Vertical Deviation,Heterophoria,Heterotropias,Hypertropia,Non-Concomitant Strabismus,Nonconcomitant Strabismus,Phorias,Squint,Strabismus, Comitant,Strabismus, Noncomitant,Convergent Comitant Strabismus,Mechanical Strabismus,Comitant Strabismus,Comitant Strabismus, Convergent,Deviation, Dissociated Horizontal,Dissociated Horizontal Deviations,Dissociated Vertical Deviations,Heterophorias,Heterotropia,Horizontal Deviation, Dissociated,Hypertropias,Non Concomitant Strabismus,Noncomitant Strabismus,Phoria,Strabismus, Concomitant,Strabismus, Convergent Comitant,Strabismus, Mechanical,Strabismus, Non-Concomitant,Strabismus, Nonconcomitant