Dissociated Vertical Deviation
نویسندگان
چکیده
DOS Times Vol. 12, No. 3 September, 2006 Dissociated Vertical Deviation (DVD) is one of the least understood forms of strabismus. It was first described by Stevens as double vertical strabismus, other common names given to this anomaly are, Alternating hyperphoria (Crone), Anaphoria / anatropia (Stevens), Periodic vertical squint (Anderson), Strabismus sursoadductorius (Cords). The term "Dissociated Vertical Deviation" was given by Bielschowsky (1938). This anomaly is intermittent and is characterised by an upward excursion, excyclotorsion, lateral movement. Uniqueness of DVD is that it violates Herring's law of ocular motility. No movement is seen in the fixing eye when the deviated eye returns for refixation. Traditionally, the upward excursion is labelled as Dissociated Vertical Deviation; the excyclotorsion is called as Dissociated Tortional Deviation and the lateral movement is termed as Dissociated Horizontal Deviation. All these three components are labeled as dissociated strabismus complex.
منابع مشابه
Dissociated vertical deviation: evidence of abnormal visual pathway projection.
Abnormalities in visually evoked responses have been used to demonstrate abnormal optic nerve fibre projections in human albinos, who have anomalous nystagmoid movements. Using visually evoked potentials we tested the hypothesis that patients with dissociated vertical deviation (another group with anomalous nystagmoid movements) may have abnormal visual evoked responses similar to those of albi...
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Flash visually evoked cortical potentials have been recorded in three groups of age- and sex-matched subjects; one comprised of subjects with dissociated vertical deviation, one comprised of subjects with oculocutaneous albinism and one group of controls. The latency of the major positive (P2) component did not show statistically significant contralateral lateralization on monocular stimulation...
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We studied the relation between vertical eye movements and binocular torsion in five subjects with dissociated vertical deviation (DVD). During trials, subject viewed a well illuminated Snellen letter chart, with both eyes uncovered during 4 seconds, Subsequently, DVD was induced by covering one eye during 4 seconds. Finally, both eyes were uncovered during 4 seconds. Several trials were record...
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OBJECTIVES To test the previous findings of Enright that disparity-induced vertical vergence is mediated primarily by the oblique muscles, and to relate this normal eye movement pattern to the eye movement pattern seen in subjects with dissociated vertical deviation. METHODS Sixteen normal volunteers underwent 55 measurements of the cycloversion associated with prism-induced vertical vergence...
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OBJECTIVE To examine the results of reversed fixation testing in patients who develop consecutive exotropia after surgery for infantile esotropia. METHODS The reversed fixation test was performed prospectively in 28 patients who developed consecutive exotropia after surgery for infantile esotropia. All patients were assessed for adduction weakness, latent nystagmus, dissociated vertical diver...
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