Cerebellar Syndromes

Anatomy

The cerebellum is an important structure responsible for motor planning, timing, and execution. It is composed of 3 broad structures with different roles:

  • The cerebrocerebellum: complex motor planning
  • The spinocerebellum: maintenance of posture and gait
  • The vestibulocerebellum: processing vestibular inputs to compute head position in space

Lesions to different parts of the cerebellum present differently:

  • Cerebrocerebellum >> ipsilateral limb ataxia
  • Spinocerebellum >> gait & truncal ataxia
  • Vestibulocerebellum >> vertigo & nystagmus

However there is significant overlap in these presentations and lesions often affect multiple parts of the cerebellum, producing a complex picture.

Clinical approach

The signs of cerebellar disease:

  • Ataxia
    • Gait
    • Truncal
    • Limb: dysmetria, dysdiadochokinesis
  • Eyes
    • Saccadic intrusions
    • Nystagmus: can be in any direction
  • Speech: stuttering dysarthria

Other things to look for on examination:

  • Localising signs:
    • Cranial nerve signs
    • Horner’s syndrome
    • Long tract signs
  • Evidence of a cause

Causes

  • Infective: any cause of meningo-encephalitis, esp VZV, listeria
  • Neoplastic: compressive, paraneoplastic
  • Vascular: infarction or haemorrhage
  • Inflammatory: MS
  • Toxins: alcohol, drugs (antiepileptics, chemotherapy)
  • Endo/metabolic: B1, B12, vit E, copper, hypothyroid, hypocalcaemia
  • Degenerative: Friedrich’s ataxia, SCAs…