Intermediate
Technical
In the Industry Vocabulary Test
nystagmus
Pronunciation: ni-STAG-muhs
Involuntary rhythmic eye movements that can indicate vestibular or neurological dysfunction.
Full Definition
Nystagmus refers to involuntary, repetitive, oscillatory movements of the eyes that can be horizontal, vertical, or rotatory. It may be physiological (such as optokinetic nystagmus) or pathological, indicating dysfunction of the vestibular system, cerebellum, or brain stem. Clinical examination focuses on the direction, amplitude, and triggering factors of nystagmus. The condition can be congenital or acquired, and its characteristics help localize neurological lesions and guide treatment decisions.
Usage
Usage note: Always specify direction and characteristics (horizontal, vertical, rotatory, pendular vs. jerk).
In Context
- "Physical examination revealed horizontal nystagmus with the fast phase to the right." — Vestibular function assessment
- "The patient's nystagmus improved following vestibular rehabilitation therapy." — Therapy progress note
Also known as
eye oscillations
Don't confuse with
saccadic intrusions
opsoclonus