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Diseases presenting nystagmus
Some of the diseases which present nystagmus as a pathological sign are:
Head trauma (the most common cause in young people)
Stroke (the most common cause in older people)
Ménière’s disease and other balance disorders
Multiple sclerosis
Brain tumors
Wernicke-Korsakoff syndrome
Encephalopathy
Lateral medullary syndrome
Aniridia
Optic nerve hypoplasia
Albinism
Noonan syndrome
Pelizaeus-Merzbacher disease
Causes
Congenital nystagmus occurs more frequently than acquired nystagmus, is not
associated with other disorders (such as refraction errors or diplopia) and is
usually mild and non-progressive. The affected persons are not aware of their
spontaneous, small-amplitude eye movements.
Congenital
Infantile:
Idiopathic
Albinism
Aniridia
Leber's congenital amaurosis
Bilateral optic nerve hypoplasia
Bilateral congenital cataracts
Rod monochromatism
Optic nerve or macular disease
Persistent hyperplastic primary vitreous
Latent nystagmus
Nystagmus blockage syndrome
Acquired
Visual loss (e.g. dense cataract, trauma, cone dystrophy)
Toxic/metabolic (e.g. alcohol intoxication, lithium, barbiturates,
phenytoin(Dilantin), salicylates, benzodiazepines, phencyclidine, other
anticonvulsants or sedatives, Methylenedioxymethamphetamine, Wernicke's
encephalopathy, thiamine deficiency)
Central nervous system disorders (e.g. thalamic hemorrhage, tumor, stroke,
trauma, multiple sclerosis)
Non-physiologic
Diagnosis
Nystagmus can be clinically investigated by using a number of non-invasive
standard tests. The simplest one is to irrigate an external auditory meatus with
warm or cold water. The temperature gradient provokes the stimulation of the
vestibulocochlear nerve and the consequent nystagmus. The resulting movement of
the eyes may be recorded and quantified by special devices called
electronystagmograph (ENG), which is a form of electrooculography (an electrical
method of measuring eye movements using external electrodes) or even less
invasive devices called videoonystagmograph (VNG), which is a form of
videooculography(VOG) (a video-based method of measuring eye movements using
external small cameras built into head masks). Special swinging chairs with
electrical controls are also used in this test to induce rotatory nystagmus.
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