Neurology: Dizziness Flashcards
What kind of stroke or infarction leads to upbeat nystagmus and downbeat nystagmus?
Brainstem/cerebellar stroke: upbeat
Vertebrobasilar infarction: downbeat
Describe Vertigo.
False sensation of movement (spinning, swaying, tilting) due to dysfunction of the vestibular system.
Where do anomalies occur that can lead to downbeat nystagmus?
Cervico-medullary junction
-ex. Arnold Chiari malformation
What is Spasmus nutans?
A pediatric disorder characterized by:
- Ocular oscillations
- head nodding
- torticollis
It usually resolves on its own.
What are some characteristics of presyncope?
- near fainting
- lightheadedness
- warmth
- diaphoresis (excessive sweating)
- visual blurring
Describe the anatomical lesion, type of nystagmus, habituation and associated symptoms of Central Vertigo.
- brainstem or cerebellum lesion
- immediate or delayed, horizontal, vertical, rotary, and changing nystagmus
- associated cranial nerve signs
- NO habituation
Describe the anatomical lesion, type of nystagmus, habituation, and associated symptoms of Peripheral Vertigo.
- involves inner ear
- delayed, horizontal, rotary and non changing nystagmus
- fast phase to normal ear and may have hearing loss or tinnitis
- habituates
What is the Dix-Hallpike maneuver used for?
Illicit a patient’s vertigo (if the physician suspects vertigo) by alternating head positions.
Describe the findings in the Dix-Hallpike maneuver for peripheral vs. central vertigo.
- onset
- fatigue
- intensity and direction of vertigo
Peripheral:
- latent onset, lasting less than 1 minute
- fatigues with repitition
- one direction w/ severe vertigo
Central
- immediate onset of vertigo
- longer than 1 minute
- no fatigue
- changing direction w/ less severe vertigo
Describe Benign Paroxysmal Positional Vertigo and its pathophysiology.
-vertigo aggravated by head movement, lasting only seconds. Nystagmus is similar to peripheral vertigo.
Caused by canalithiasis (calcium carbonate stones in the semicircular canals)
-this explains the positional nystagmus b/c whenever the head is positioned a certain way, the stones are allowed to move and influence the hair cells in the canals
What is the main treatment for BPPV?
Epley Maneuver (canalith repositioning)
How does BPPV differ from Meniere Disease?
MD has:
- both nausea and vomiting
- vertigo lasts minutes to hours
- deafness
What is the cause of Meniere Disease?
Increase in endolymphatic volume with ballooning of the cochlear duct, utricle, and saccule.
What are 3 treatments for Meniere Disease?
- Restrict salt in diet
- Diuretics
- Surgery
How do patients present with vestibular neuritis?
Severe sudden vertigo without any hearing loss. This is because the virus that causes the inflammation only affects the vestibular portion of CN VIII.
