The most common causes of dizziness, vertigo, and nystagmus on the USMLE Step 2 CK exam

by / Monday, 21 February 2011 / Published in Internal Medicine

Dizziness/Vertigo

  • All pts with vertigo will have a subjective sensation of the room spinning around them.
  • Often associated with nausea and vomiting
  • All pts with vertigo will have nystagmus
  • Generally all patients wtih vertigo should have MRI of the internal auditory canal.

Following table summarizes pres of a number of vertigo-causing conditions:

Disease Characteristics Hearing Loss/ Tinnitus
BPV Changes w/ position NO
Vestibular neuritis Vertigo occurs w/o position change NO
Labyrinthitis Acute YES
Meniere’s disease Chronic YES
Acoustic neuroma Ataxia YES
Perilymph fistula Hx of traum YES

BPV

  • Vertigo alone w/ no loss of hearing,no tinnitus, no ataxia.
  • Positive dix-hallpike maneuver
  • Treat with meclizine(antivert)

Vestibular Neuronitis

  • An idiopathic inflammation of the vestibular portion of CN8.
  • No hearing loss or tinnitus because only vestibibular portion is affected.
  • Most likely to be a viral cause
  • Not related to change in position
  • Treat with meclizine

Labyrinthitis

  • Is inflammation of the cochlear portion of the inner ear.
  • There is hearing loss as well as tinnitus.
  • Is acute and self-limited
  • Treat with meclizine

Meniere’s Disease

  • Same pres as labyrinthitis (vertigo, tinnitus, hearing loss) but meniere’s is chronic with remitting and relapsing episodes.
  • Treat with salt restriction and diuretics.

Acoustic Neuroma

  • A tumor of CN8 that can be related to neurofibromatosis (von Recklinghaus’s).
  • Presents with ataxia in addition to hearing loss, tinnitus, and vertigo.

Diagnosis:

  • MRI of internal auditory canal

Treatment:

  • Surgical resection.

Perilymphatic Fistula

  • Head trauma or any form of barotraumas to the ear may rupture the tympanic membrane and lead to a perilymph fistula.

Wernicke-Korsakoff Syndrome

Presents with the following:

  1. History of chronic heavy ETOH use
  2. Confusion with confabulation
  3. Ataxia
  4. Memory loss
  5. Gaze palsy and/or ophthalmoplegia
  6. Nystagmus

Diagnosis:

  • Do a head CT
  • Vitamin B12 level
  • TSH/T4 level
  • RPR/VDRL
  • Presence of memory loss

Treatment:

  • 1st give thiamine then give glucose.

Leave a Reply

TOP