Lecture 11: Cerebellum disease

Question 1

On what side of the body will Cerebellar Lesions on one side affect

Answer 1

Lesions on one side will give rise to abnormalities on the same side of the body.

eg. Midline lesions cause midline problems with gait, dysarthria and swallowing

Question 2

What are the afferents to and efferents from the cerebellum

Answer 2

Afferents from: SC, vestibular nuclei via inferior olivary nucleus, pontine nuclei

Efferents to: UMN via thalamus. LMN via vestibular nuclei, reticular formation and red nucleus

Question 3

What are the 5 symptoms that make up Ataxia - a sign of cerebellar disease

Answer 3

• Eye movements: oscillopsia/blurrying
• Orobuccal: speech/swallow difficulties
• Limbs: clumsiness, slow
• Truncal: problem w balanced sitting
• Gait: unsteadiness, falls common

Question 4

What is dysphagia

Answer 4

Dysphagia is difficulty in swallowing particular tough textures or mixed textures.

Question 5

What are 4 associated symptoms of cerebellar disease - what does associated mean

Answer 5

Associated means that the cause of damage may have also affected other areas of the brain- mostly brainstem. Eg. blockage of post cerebral artery can damage

• > Occipital lobe/brain stem Visual: diplopia, hemianopia
• > Medulla connections to ear Vertigo: sensation of movement
• > Nausea and vomiting
• > Pons+ reticular formation- impaired consciousness

Question 6

What are some abnormal eye movement cerebellar disease signs

Answer 6

Nystagmus: rhythmic oscillatory eye movements with a fast and slow phase -slow phase is abnormal caused by drifting off target
Nystagmus is worse in the direction of the fast phase of the nystagmus.

Right +Left beating nystagmus on gaze to the right + left=
Gaze evoked nystagmus: regular depending on gaze.

Square wave jerks: rapid subtle movements of the eye taking it off the target down and then another to put it back on.

Question 7

How does dysarthria (tongue not moving well) present. Aka scanning speech

Answer 7

• Laboured, Slurred speech - same emphasis/monotony
• Staccato speech pattern- one syllable at a time
• Rapid tongue movements are slowed when repeating a consonant.
• difficulty making self understood.

Question 8

How does limb ataxia present - cerebellum cannot judge distance

Answer 8

• Intention tremor: tremor amplitude gets greater as endpoint reaches the visually intended target
• Past pointing : dysmetria: Go to reach for something, goes past it and then recorrects
• impaired rapid alternating movements eg flipping ones hand from back to front (dysdiadochokinesia):

Question 9

How does truncal and gait ataxia present (sometimes only sign) if vermis one affected - eg. damaged by alcohol.

Answer 9

• Broad based gait:
• Sways to either side:
• irregular steps in time/distance which can be exaggerated with heel toe walking in a straight line.

Question 10

What are the signs of a pure cerebellar disease -

Answer 10

There is no muscle weakness

• normal to reduced tone
• normal reflexes and sensation

Question 11

What are 8 causes of cerebellar disease

Answer 11

1. Metabolic toxin= alcohol/B12
2. Congenital abnormality: Arnold chiari malformation- cerebellum herniates into the foramen magnum
3. Vascular disease: stroke
4. Inflammation/ demyelination due to eg. multiple sclerosis periventricular demylination.
5. Tumours
6. Infections: cerebellitis

7: Degenerative diseases of the cerebellum: aquired or genetic
8. Head trauma