Vestibular & Cerebellar Disorders Flashcards
Vestibular System Function
- Linear/rotational accelerometer of the head:
- Balance control
- Head/neck position
- Eye movement
Vestibular Syndrome Signs
- Head tilt
- Vestibular ataxia: leaning, falling, rolling
- Pathologic nystagmus: resting, positional
- Strabismus
- Nausea, vomiting
Central Vestibular Syndrome Signs
- Mentation:
- CN deficits:
- Nystagmus:
- Horner’s syndrome:
- Vestibular ataxia:
- Proprioceptive deficits:
- UMN paresis:
- Multifocal CNS signs:
- Mentation: Somnolence, stupor, coma
- CN deficits: VIII ± V-XII
- Nystagmus: Horizontal, rotary, vertical, changing
- Horner’s syndrome: Rare
- Vestibular ataxia: Present
- Proprioceptive deficits: Possible
- UMN paresis: Possible
- Multifocal CNS signs: Possible
Peripheral Vestibular Syndrome Signs
- Mentation:
- CN deficits:
- Nystagmus:
- Horner’s syndrome:
- Vestibular ataxia:
- Proprioceptive deficits:
- UMN paresis:
- Multifocal CNS signs:
- Mentation: Alert
- CN deficits: VIII ± VII
- Nystagmus: Horizontal or rotary only
- Horner’s syndrome: Possible
- Vestibular ataxia: Present
- Proprioceptive deficits: no
- UMN paresis: no
- Multifocal CNS signs: no
horner’s syndome - signs
- Miosis > minimum clinical sign
- Ptosis
- Protruding nictitans
- Enophthalmos
horners syndrome nerves pathway, sites for injury
brain > T1, T2, T3 > cervical ganglion, through tympanic bulla > eye
what nerves can be affected by damage to the tympanic bulla?
CN 7 and 8
Otitis Media/Interna
- pathogenesis
- neuro signs possible
Pathogenesis: bacterial > fungal
– Extension of otitis externa
– Foreign body
– Oral/pharyngeal cavity extension (auditory tube)
– Hematogenous
<><><><>
Clinical Signs: CN VIII
– ±CNVII
– ± Horner’s
Otitis Media/Interna
Diagnosis:
– Otoscopic exam
– Schirmer Tear Test > cranial nerve 7 innervates lacrimal glands - eye will start to dry, get KCS
– Brainstem Auditory Evoked Response (BAER)
– Bulla Radiographs
– Myringotomy
– CT/MRI
Otitis Media/Interna
Treatment:
– Caution: topical treatment/scrubs
<><>
Medical
- Systemic Antibiotics (4-6wk)
> C&S
> Clavamox, Cephalosporin, Fluoroquinolone
<><>
Surgical
- Bulla Osteotomy (drain, debride)
– Brainstem Auditory Evoked Response (BAER)
what is this test?
- put earbuds in electrodes on head, pick up brain’s response when you play a sound
> pick up classic wave pattern as various parts of the brainstem pick up this noise…
> abnormal if we see a flat line - can do right and left sides
Idiopathic Vestibular Disease
- origin / localization
- common cause?
- who gets it?
- history
- clinical signs
- Peripheral
- Dogs: most common cause, aka geriatric vestibular disease
> German Shepherd dogs - Cats: all ages
- Hx: acute/peracute, severe, non-progressive
- Clinical Signs: CN VIII, unilateral
Idiopathic Vestibular Disease Diagnosis, treatment, prognosis
Diagnosis: by exclusion
<><>
Treatment: supportive
– Anti-nauseants
– IV fluids
<><>
Prognosis: Good
– Initial improvement in 2-3 days
– Resolves in 2-4 weeks
– Usually residual head tilt
Central Vestibular: Dx Tests
Bloodwork: CBC/profile/UA/Thyroid panel
3v thoracic rads + abdominal US
Blood pressure
Otoscopic exam
BAER
Brain MRI or CT
CSF analysis
Bilateral Vestibular Syndrome
Clinical Signs:
- Wide side-to-side head excursions
- Wide-based stance
- Ataxia – staggering to both sides
- NO head tilt
- NO nystagmus
> No spontaneous
> No physiological
