Transcript cerebellar hemisphere

Cerebellar dysfunction,
syndromes, signs, examination
doc. MUDr. Valja Kellerová, DrSc.
Department of Neurology
Causes od cerebellar dysfunction
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cerebrovascular disease
multiple sclerosis
alcohol, the acute intoxication
inflammatory diseases
(encephalitis)
• drugs (i.e. anticonvulsant
intoxication)
• posterior fossa tumours:
– in children - primary malignant
tumours
– in adults - acoustic neuroma,
meningeoma, metastasis
Lesion location 1
• vermis (damage to midline
structures) - paleocerebellar
syndrome - disturbance of
equilibrium
• hemisphere structures of the
cerebellum - neocerebellar
syndrome - impaired limb coordination
• cerebellar connections to other
areas
– nystagmus
– ocular dysmetria - an overshoot during
fixation of gaze
– scanning dysarthria, explosive speech
Lesion location 2
• vermis – paleocerebellar sy
disturbance of equilibrium:
– unsteadiness on standing,
walking, sitting - truncal
ataxia
– gait is broad based and
reeling
– eye closure does not
affect balance
Lesion location 3
• cerebellar hemisphere neocerebellar sy
impaired limb co-ordination
(ipsilateral to the side of the
lesion):
– ataxia
– dysmetria, overshooting
– dysdiadochokinesia
– intention tremor
– pendular reflexes
– rebound phenomenon…
Signs of cerebellar dysfunction,
examination 1
• passivity (hypotonia) during passive movements:
– resistance to passive movements is diminished
– the joints may be passively hyperextended
– pendulousness is increased
• Examination:
(head: flexion, rotation, inclination is in a greater extent)
upper limbs:
– passive shaking of the hand
• larger excursions
• larger number of swings
Signs of cerebellar dysfunction,
examination 2
• Passivity – examination:
• "ressaut" (arm bounce) – after release of the arms they
fall and rebound from the trunk
– many rebounds
– excessive swinging
• "succusion of the trunk" – passive rotation of the
trunk (by moving the standing patient´s shoulders back and
forth)
– excessive arm swings
– larger number of swings
Signs of cerebellar dysfunction,
examination 3
• Passivity: upper limbs:
• pendular reflexes, pendulousness
in the triceps reflex
(larger number of oscillations)
• lower limbs:
– passive shaking the foot (larger
excursions and number of swings)
– passive rotation of thighs (larger
extent)
– pendular reflexes in the knee jerk
(patellar reflex) in the sitting
position (larger number of
oscillations)
Signs of cerebellar dysfunction,
examination 4
• Dysmetria:
– finger-nose test (nosefinger-nose test)
• ataxia, past pointing,
overshooting
• intention tremor
– grasp of a pencil, of a glass –
fingers spread out
– hand reversal (from
supination to pronation) –
overshooting
– heel-knee (shin) test ataxia
Signs of cerebellar dysfunction,
examination 5
• rebound phenomenon (Stewart-Holmes) – flexion of the
forearm against resistance, sudden release, normal reaction – prompt
control, abnormal - insufficient control, dysmetria (striking the
head)
Signs of cerebellar dysfunction,
examination 6
• Dysdiadochokinesia:
• of the tongue
• upper limbs:
– classic (pronation-supination of the
forearms) – chaotic
– flexion-extension of the fingers or of
the forearm
– knee pat test (pat a cake) – pronation
and supination, to pat the knee with the palm
and dorsum of one hand
• lower limbs:
– heel-buttock test
Signs of cerebellar dysfunction,
examination 7
• Dyssynergia:
• combined flexion of lower limbs and the trunk
("small dyssynergia") – lifting legs during
sitting up (without hand support)
Signs of cerebellar dysfunction,
examination 8
• Dyssynergia:
• retroflexion of the trunk
(while standing)
– normal: flexion of knees
– dyssynergia: without
flexion of knees,
falling backward
"like a board"
Signs of cerebellar dysfunction,
examination 9
• Dyssynergia:
• truncal ataxia – when seated,
falling to one side or backwards
• axial dysfunction ("great
dyssynergia") – disturbance of
equilibrium with unsteadiness on
standing and walking:
– standing – broad based,
swaying (even with eyes
open)
– walking – broad based gait,
reeling, ataxic gait, irregular
Signs of cerebellar dysfunction
Signs of cerebellar dysfunction,
examination 10
• Writing and drawing:
• writing a short sentence – large, macrographia
• writing large block letters, large diameter
• writing without support of the hand – intention tremor
– hooks at the beginning of lines
Signs of cerebellar dysfunction,
examination 11
• Writing and drawing:
• zig-zag line
– horizontal
– vertical - irregular
• connecting two points
– horizontal line
– vertical line
• past pointing
• overshooting
Signs of cerebellar dysfunction,
examination 12
• Speech:
– scanning dysarthria, explosive speech, ataxic
dysarthria, staccato
– excessive loudness
• Eye movement abnormalities:
• nystagmus (a coarse nystagmus toward the side of the
lesion, involvement of cerebellar connections to the
vestibular nuclei)
• ocular dysmetria when the eyes voluntary
fixate, overshooting
Conclusion
Right or left handed patient?
Dominance of one cerebellar hemisphere !
In the right handed patient, the dominant cerebellar
hemisphere is the right (ipsilateral) !
Conclusion: (according prevalence of signs)
•
paleocerebellar syndrome
•
neocerebellar syndrome
•
mixed (global)