Clinical- 8 Flashcards
True or False: dizziness = vertigo.
False
What is dizziness?
sensations of light-headedness, faintness or giddiness. NOT associated with an illusion of movement.
ILLUSIONS, MICHAEL. TRICKS ARE WHAT WHORES DO FOR MONEY.
What is vertigo?
The illusion that you’re moving but you’re not actually moving.
“Lucille #2”
What happens in peripheral vertigo?
lesions that affect the labrynth of the inner ear, or VIII
What is central vertigo?
lesions of the brainstem vestibular nuclei or their connections, possible froma cerebral Cx lesion
QUICK FIRE: I’ll give a Sx and you tell me whether it’s peripheral or central vertigo. Ready?
Contant, less severe vertigo
Central
Nystagmus always present, unidirectional, never vertical
Peripheral
Tinnitus/heading loss often present
Peripheral
Usually has brainstem or cerebellar signs
Central
Verigo is intermittent, brief, and more severe
Peripheral
Nystagmus possible, can be uni- or bidirectional, can be vertical
Central
There are no intrinsic brainstm or cerebellar signs
Peripheral
Rarely is there tinnitus/hearing loss
Central
What is ataxia?
incoordination or clumsiness of movement that s not the result of muscular weakness
What is vestibular ataxia?
gravity-dependent (only when walking, standing), incoordination from the same central and peripheral lesions that cause vertigo
What is cerebellar ataxia?
irrgular rate, rhythm, amplitude and force of voluntary movements caused by lesions of the cerebelum or its afferent or efferent connections in the peduncle.s, red nucleus, pons, or spinal cord.
What is sensory ataxia?
impaired sensation of propriocepton and vibratory sense form disorders that affect those pathways.
True or False: There is NO vertigo, nystagmus and dysarthria in sensory ataxia.
True
Demonstrate the Dix-Hallpike technique (5 steps)
- sit pt on table with eyes forward
- quickly bring them supine with head over edge of table (30-45 deg)
- repeat with head turned 45 deg to the R
- repeat with head turned 45 deg to the L
- observe for nystagmus or vertigo
Positional nystagmus and vertigo are usually assoacited with lesions where?
peripheral vestibular lesions
What are the characteristics of peripheral nystagmus?
tends to remit spontaneously (fatigue), reduces with repetition.
Caloric testing can test disorders from where?
vestibuloocular pathway
What are the expected results from COLD water caloric testing?
Remember COWS (cold opposite, warm same)
Slow phase to irrigated ear, fast to opposite ear (side of nystagmus)
What are the expected results from WARM water caloric testing?
coWS
slow phase opposite of irrigated ear, fast to same side
What are the causes for the FAILURE of nystagmus to form fromcaloric testing?
unilateral labrynthine, vestibulocochlear n. or vestibular N dysfxn
What is the most common cause of vertigo of peripheral origin, and is caused by canalolithiasis?
Benign positional vertigo
What are the Sx of BPV?
breif episodes of severe vertigo, N/V, worse in lateral decubitus position with affected ear down,no hearing loss. can be peripheral or central Sx.
BPV- Tx
respositioning (epley) maneuvers that use gravity to move the canaloliths out of the SC canals and into the vestibule where they can be reabsorbed.
Define: disorder that has repeated episodes of vertigo lasting minutes-days and accompanied by tinnitus and progressive sensorineural hearing loss.
Meniere’s disease
Meniere’s- etiology
from endolympahtic hydrops, sporatic, men > women, 20-50 y/o, familial related to mutation in cochlin gene.
Meniere’s- Sx
tinnitus, heading loss, sense of fullness in the ears, vertigo, N/V. Recurring intervals from weeks-years.
Menieres- clinical findings
spontaneous horizontal or rotatory nystagmus, impaired vestibular fxn with caloric testing, low-freq pure-tone hearing loss.
Meniere’s- Acute Tx
symptomatic with antihistamines, benzos, other vestibule-suppressant drugs
Meniere’s- management
low-salt diet, diuretics, transtympanic insillation of gentamicin or dexamethasone.
Define: disorder of spontaneous vertigo of no apparent cause that resolves spontaneously, causes NO hearing loss, and shows no signs of CNS dysfxn.
Vestibular neuronitis
Vestibular neuronitis- Sx
vertigo, N/V up to 2 wks, recurring Sx
Vestibular neuronitis- clinical findings
pt wants to lie of side with dysfxnl ear UP, nystagmus with fast phase AWAY from affected side (always present)
Vestibular neuronitis- Tx
10-14 days of prednisone (antiinflamm) and a vestibulosupressant
What are the 3 antihistamines used for vertigo?
meclizine, promethazine, mimenhydrinate
What is the 1 anticholinergic used for vertigo?
scopolamine (remember this from pharm??)
What is the 1 benzo used for vertigo?
diazepam
What are the 2 sympathomimetrics used for vertigo?
amphetamine, ephedrine
CNS stuff
Define: the most common type of tumor is an acoustic neuroma, but meningiomas and epidermoidal cysts can cause this type of tumor too. Close to V-XII from the braimstem.
Cerebellopontine angle tumor
Which AD disorder causes bilateral acoustic neuromas?
NF2
CPAT- Sx
insiduous hearing loss, headache, vertigo, gait ataxia, facial pain, tinnitus, sensation fo fullness in the ear, facial weakness, unsteadiness.
See a trend here? V, VII, VIII affected.
What are the 5 drugs that cause toxic vestibulopathies?
- alcohol (>40mg/dL in blood)
- aminglycosides
- salicylates
- quinine and quinidine
- cisplastin (antineoplastic drug)
What is the pathogenesis of cerebellar stroke?
infarct in one of the 3 arteries that supplies the cerebellum (superior cerebellar, AICA, and PICA)
What are the clinical features of cerebellar strokes?
IPSILATERAL limb ataxia, lateroplusion and hypotonia
can also have contralateral hemiparesis
Cerebellar strokes- Dx
CT or MRI
Cerebellar strokes- Tx
brainstem compression indicates surgical decompression and resection of infarcted tissue.
Cerebellar hemorrhage- pathogenesis
hypertension; anticoagulation, arteriovenous malformation, blood dyscrasia, tumor, trauma
Cerebellar hemorrhage- Sx
sudden headache, gait ataxia, IL gaze palsy, IL peripheral facial palsy, IL corneal reflex depression
Cerebellar hemorrhage- Dx
DO NOT do an LP cuz of possible herniation. CT or MRI
Cerebellar hemorrhage- Tx
surgical evacuation
Ataxia Telangectasia- pathogenesis
autosomal recessive disorder; onset in infancy; results from loss-of-function mutation in the ataxia-telangiectasia mutated gene (ATM) which codes for a Ser/Thr protein kinase causing a defect in repair of dsDNA breaks
Ataxia telangiectasia- clinical Sx
progressive cerebellar atxia, oculocutaneous telangiectasia, sinopulmonary infections, lymphoid tumors
Friedrich ataxia- onset
autosomal recessive disorder; onset in childhood (avg age = 13); avg age at death is 40 yrs; displaces anticipation;
Friedrich ataxia- mutation
expanded GAA trinucleotide repeat in noncoding region of FXN gene → loss of function mutation in frataxin
Friedrich ataxia- defect
degeneration of dorsal root ganglia, large myelinated peripheral sensory nerve axons, corticospinal tracts, and dentate nuclei;
Friedrich ataxia- Sx
progressive gait ataxia, followed by limb ataxia, dysarthria, and sensory gait ataxia; knee and ankle areflexia, impaired dorsal column modalities; leg weakness; Babinski sign; pes cavus; kyphoscoliosis; chronic restrictive lung disease; cardiomyopathy; optic atrophy and diabetes mellitus
