Lec 38 Cerebellum Clinical Correlations Flashcards
Will a unilateral cerebellar lesion result in ipsilateral or contralateral deficit?
ipsilateral
Which outputs from cerebellum course in the superior cerebellar peduncle?
all outputs EXCEPT vestibular
What is path of non-vestibular outputs from the cerebellum?
- ascend in the ipsilateral cerebellar peduncle and decussate in the midbrain
- target red nucleus OR cerebral cortex via thalamus
- become descending motor tracts [rubrospinal and corticospinal] which then cross again as they descend ending up back on the ipsilateral side
What are cardinal features of cerebellar dysfunction?
- hypotonia
- ataxia
- dysarthria
- tremor
- ocular motor dysfunction
What are classic symptoms of cerebellar vermis syndrome?
mostly affect trunk
- wide based stance and gait
- difficulty maintaing posture/balance
- gait ataxia
- normal or slight arm coordination impairment
- nystagmus, ocular dysmetria
What is one potential effect of cerebellar vermis syndrome due to its location?
- caudal vermis is near 4th ventricle
- large mass lesion/edema of vermis can obstruct 4th ventricle
- -> obstructive hydrocephalus
What is relationship alcoholism and cerebellar vermis syndrome?
- alcohol and thiamine deficiency causes major cerebellar vermis degeneration
- can cause vermis syndrome
What are signs of hemispheric syndrome?
most affect limbs
- poor coordination ipsilateral limb movement [most noticeably speech + finger movements]
- impaired rapid alternating movement
- intention tremor [when voluntary movements performed]
- dysmetria [impaired finger-nose/heel-knee-shin tests]
- scanning or dysarthric speech
What is dysmetria?
- inability to stop a movement at proper place
- seen in impaired finger to nose or heel-kneel-shin tests
What is pancerebellar syndrome?
- combination of all other syndromes
- bilateral signs involving trunk, limbs, cranial musculature
What are possible etiologies of pancerebellar syndrome?
- usually infectious/parainfectious
- hypoglycemia
- paraneoplastic disorder
- toxic-metabolic disorder
What types of oculomotor dysfunction in cerebellar syndromes? can they help localize area of lesion?
frequently nystagmus especially in midline cerebellar lesions
- cannot help localize to specific area of cerebellum
What kind of cerebellar syndrome should you think if you see:
- wide based gait
- nystagmus
- really bad headache
think cerebellar vermis syndrome
headache = due to 4th ventricle compression
What are some possible etiologies of cerebellar vermis syndrome?
- alcoholism, thiamine deficiency
- large mass, lesion, edema
What are some possible etiologies of cerebellar hemispheric syndrome?
- infart
- neoplasm
- abscess
What kind of gait do you see in cerebellar dysfunction? mid-cerebellum vs lateral cerebellum?
- ataxic gait = walk is staggering/ lurching/ wavering
- not benefitted by pts view of his surroundings = no romberg
- mid-cerebellum –> movement in all directions
- lateral cerebellum –> staggering/falling toward side of lesion
What is position of feet in cerebellar gait?
- ataxia less when pts stand on broad base [feet wide apart]
Does coordination improve in cerebellar syndrome pts with eyes open/closed?
- not improved by visual orientation
How does cerebellar ataxia differ from posterior column disease ataxia?
posterior column disease = + romberg sign = ataxia made worse with eyes closed
cerebellar = negative romberg
Where do you see cerebellar hypotonia? which type of lesions?
- usually in acute cerebellar hemispheric lesions
- less often seen in chronic lesion
- ipsilateral to side of cerebellar lesion
- more noticeable in upper limb
What should you think if hypertonia in cerebllar disease?
- may reflect compression of brainstem/corticospinal tract
What do finger-nose and heel-shin tests tell you?
- evaluate cerebellar dysmetria
- if its jerky = sign of dysmetria
- cerebllar dysmetria usually due to cerebellar hemispheric function
What is dysdiadochokinesis?
- decreased ability to perform rapidly alternating movements
What does rapid alternating movement test tell you?
- evaluate for dysdiadochokinesis
