Central Vestib Disorders Flashcards
(13 cards)
What is the most common symptom of vertebrobasilar insufficiency (VBI) distribution TIA?
Vertigo
What are the associated symptoms with TIA of the posterior circulation (VBI) ?
diplopia, visual field defects
what are the risk factors of TIA
HTN, a-fib, smoking, diabetes, hyperlipidemia
What test would you use to reticulate vascular insufficiency? Describe how the test is done.
Vertebral artery compression test: supine with neck extension and full rotation near end range - this further occludes the flow in the stenotic artery
Who do you refer to if you get a positive vertebral artery compression test?
vascular neurologist, CTA/MRA, vertebral artery Doppler, Holter recommended for further investigation
Explain the presentation of a common stroke - Posterior inferior cerebellar artery (PICA) stroke (Wallenberg syndrome)
Vertigo, ptosis, miosis, nausea/vomiting, “crossed” sensory findings (psi-face and contra limb involvement)
What are the mechanisms of a PICA stroke ?
cardiac embolism, vertebral artery dissection, manipulation of cervical spine?
What can cause Cerebellar Degenerative Disorders?
- Genetic
- MSA (multiple system atrophy)
- Toxins: alcohol, lithium, amiodarone, anticonvulsants - lamotrigine (lamictal) or phenytoin (Dilantin)
Explain what a Chiari malformation is
low-lying cerebellar tonsils protruding through the foramen magnum
Jeff Walter:
Maldevelopment of the back part of the skull as it doesn’t expand as posteriorly as it should and this shoves the brain (and cerebellum) forward and it butts into the upper brain stem
So pressure goes down and causes a herniation of the midline cerebellar tissue through the foramen magnum
What are the common symptoms of a Chiari malformation?
- Exertional symtpoms (e.g., slowly progressive headache at the base of the skull, neck pain, imbalance, blurred vision/oscillopsia (downbeating nys.) dizziness
- weakness or sensory disturbances in the upper extremity
What is a hall mark feature of MS when examining oculomotor movement? Describe the eye movement
Internuclear Ophthalmoplegia (INO):
- ADDUCTION impairment noted on the AFFECTED side with lateral gaze
- nystagmus will be noted in the ABDUCTED eye only
- damage to the Medial longitudinal fascicles (MLF)
What is the difference with a partial INO?
Affect eye has a DIMINISHED ability to adduct one eye when gazing laterally. They might exhibit nystagmus in the abducted eye
What is White matter disease?
- Increased severity of white matter lesions
- present in approximately 50% of subjects over 60 YO
- more common with age, vascular risk factors, migraine, diabetes, vitamin B6 deficiency, syncope/orthostatic intolerance
- more common in patients with “unexplained dizziness”
