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Flashcards in cerebellum Deck (18):
1

vermis and floculondular lobe function

proximal limb, trunk coordination
gait, balance, VOR reflexes
coordination of eye movements in relation to posture

2

intermediate hemisphere function

distal limb coordination

3

lateral hemisphere function

motor planning for extremities
distal limb movement control

4

Crossed cerebellar diaschisis (CCD)

depression of blood flow / metabolism affecting cerebellar hemisphere as a result of a contralateral focal, supratentorial lesion (infarct, radiation necrosis, following a tumor resection, etc.)

5

CCD Pathophysiology

interruption of cortico-ponto-cerebellar connections due to the infarct which then causes deafferentation and transneuralmetabolic depression of the contralateral cerebellar hemisphere

6

ataxia

ipsilateral to the cerebellar lesion
appendicular or axial
disorganized, poorly controlled or clumsy movement due to lesions in the cerebellum and its immediate connecting pathways
may be associtaed with involuntary movements

7

pseudoataxia

Lack of proper sensory input -> need for visual system to help coordinate movements
Eyes closed -> worsening of ataxia
Positive Romberg test
May also present as pseudoathetosis
Problem with large sensory fibers / posterior colums

8

asthenia

only apperent during movements, static resistance normal
easy fatigability and/or a lack of coordination or stability
inability to maintain steady force levels (astasia)

9

dysdiadochokinesia

impaired coordination of different single-joint movement components when performing alternating multi-joint movements

10

cerebellar tremor

Action / kinetic, postural
Intention
Low frequency
Present with rest, posture and action
Typically worsens with ETOH
Tremor frequency may differ between limbs

11

2 classifications of ataxias

degenerative/sporadic
hereditary/genetic (autosomal dominant)

12

Friedreich's ataxia

frequency: 1 in 40,000
trinucleotide repeat disorder (GAA)
chromose 9 encoding frataxin
begins in childhood (5-15 years old); wheelchair-bound about 10 years after signs and symptoms appear
ataxia, dysarthria and sensory loss
hypertrophic cardiomyopathy
scoliosis, diabetes, hearing loss

13

secondary ataxias

Toxic (ETOH, heavy metals, AEDs)
Autoimmune (Yo, Hu, Ri)
Vasculatr (stroke)
Structural (mass lesion, HC)
Vasculitis (Behcet)
Infectious (HIV, prions)
Demyelinating (MS)
Metabolic (thiamine – B1, B12
or vit E deficiency)
Postanoxic

14

common finding of SCAs

all have gradual onset of balance and gait difficulty, dysarthria and clumsiness of hands +/- visual symptoms

15

SCA2 clinical

□ Onset 3rd-4th decade
□ Parkinsonism
□ Axonal sensory neuropathy
□ Dysarthria, tremor, hyporeflexia
□ Slowing of eye saccades
□ Survival- 25 years (median)

16

SCA 3 clinical

Onset 3th – 4th decade
Highly variable clinical course
Parkinsonism, Dystonia
Facial – lingual fasciculations
Axonal polyneuropathy, bulging eyes
4th ventricle enlargement
Survival – 20 years (median)

17

SCA2 pathology key

cytoplasmic inclusions/aggregates

18

SCA3 pathology key

internuclear inclusions