Lecture 13: Disorders of Equilibrium Flashcards
What are the main characteristics of sensory causes of Disequilibrium?
- Proprioceptic deficit
- Visual impairment
- Compensated vestibular disorders
- Worse in dark
- Romberg sign
A positive Romberg test indicates what?
- A somatosensory dysfunction (proprioception)
*With the eyes open, three sensory systems provide input to the cerebellum to maintain truncal stability. These are vision, proprioception, and vestibular sense. When pt closes eyes during Romberg test you remove that visual sense.
A sense of impending loss of unconsciousness often associated with pallor, sweating, visual dimming or constricted fields, is known as?
Presyncope
Etiologies of Presyncope?
What can make it worse?
- Arrythmia, hypotension, vasovagal excess, pulmonary emboli, drugs
- Aggravated by: increased temperature, prolonged standng, large meals, and deconditioning
With labyrinthine dysfunction (peripheral) leading to dysequilibrium what is the vertigo like, duration of nystagmus, direction of nystagmus, and neuro symptoms?
- Intense vertigo
- Brief nystagmus
- Horizontal/diagonal nystagmus that is fixed
- Never any neuro symptoms
With central dysfunction leading to dysequilibrium what is the vertigo like, duration of nystagmus, direction of nystagmus, and neuro symptoms?
- Mild vertigo
- Persistence of nystagmus, which can be in vertical direction
- Usually some neuro symptoms
Which 4 structures are considered peripheral/labyrinthine for the maintenance of equilibrium?
- Utricle
- Saccule
- Semicircular canals
- Vestibular nerve
Most common cause of recurrent vertigo and characteristics?
- Benign Positional Vertigo
- Brief recurrent episodes of vertigo triggered by changes in head positon
What is the most comon location for debris causing Benign Positional Vertigo?
How is this diagnosed?
Direction of Nystagmus?
- Posterior semicircular canal
- Use Dix Hallpike manuever, nystagmus provoked w/ affected ear down
- Nystagmus = torsional
Why is the direction of nystagmus provoked by the anterior type of Benign Postional Vertigo significant?
- This is a more rare form
- Dix Hallpike will causes a downbeat (vertical) nystagmus, which is usually only seen in central lesions.
- Must carefully assess to rule out brainstem or cerebellar lesions!
Treatment for Benign Postional Vertigo?
- Often resolves on its own within a few weeks
- Positional exercises helpful: Sermont manuever
- Meds such as: vestibular suppressants, antiemetics, and anxiolytics
How does Vestibular Neuronitis differ from BPV?
- Spontaneous attack of vertigo, typically lasting up to 2 weeks (findings similar to BPV
- But is NOT typically positonal
What are the characteristics of Meniere’s Disease and who is most often affected?
Hallmarks?
- Recurrent episodes of spontaneous vertigo, lasting minutes to hours
- Low frequency hearing loss = Hallmark
- Tinnitus and aural fullness
- Woman are 3x more affected
Treatment for Meniere’s Disease?
- Sodium restriction
- Diuretics: thiazdies, furosemide
- Sugery: endolymphatic sac decompression
What are the characteristics of Mal de Debarquement (“Sickness of Disembarkment”)?
Duration?
Treatment?
- Illusion of movement as an after effect of travel (sea, car, train)
- Rocking, swaying feeling after getting off a boat
- Duration = usually <24 hours; sometimes longer
- Tx: meclizine, scopolamine, benzodiazepines (dizziness meds)
