EpistemisAcquired nystagmus
Specialty: Ophthalmology.
Why it occurs
- Multiple sclerosis or other demyelinating diseases affecting the brainstem or cerebellum
- Acute toxicity from anticonvulsant drugs (phenytoin, carbamazepine), lithium or benzodiazepines
- Cerebellar or pontine ischemic or hemorrhagic stroke
- Decompensated peripheral vestibular pathology or acute labyrinthitis
- Wernicke's encephalopathy secondary to chronic malnutrition or alcoholism (thiamine/B1 deficiency)
- Posterior fossa tumors
Initial workup
Computerized videonystagmography to objectively categorize the direction, amplitude, frequency and behavior of nystagmus upon visual fixation; High-resolution brain magnetic resonance imaging (MRI) focused on the posterior fossa and craniocervical junction, with administration of gadolinium contrast; Urgent analytical determination of anticonvulsant drug or lithium levels; Plasma thiamine dosage if clinically consistent.
red flags
New-onset spontaneous vertical nystagmus (up or down) or dissociated oscillatory nystagmus, associated with the presence of rapid-onset gait ataxia, dysarthria, dysphagia, constant diplopia or nuchal rigidity, indicating severe structural compromise in the brainstem, cerebellum or at the level of the craniocervical junction.
Standard management
- Gabapentin — 300 mg to 900 mg orally per day, administered under strict neurological tolerance, used as a modulator of acquired pendular nystagmus
- Memantine — 10 mg to 20 mg orally per day, NMDA receptor antagonist, indicated for the reduction of oscillopsia in patients with nystagmus of central neurological origin
- Baclofen (5 mg to 20 mg orally every 8 hours, used selectively in alternating periodic nystagmus to stabilize movements).
Educational guidance for study. It is NOT a prescription recommendation. The actual choice depends on the cause, the patient, and current guidelines.
- Area
- Ophthalmology
- Listed causes
- 6
- Treatment options
- 3