• Clinical science

Rare neurological diseases


Rare neurological diseases may be inherited, postinfectious, iatrogenic, or of unknown etiology. They can affect the brain, spinal cord, or peripheral nerves. Symptoms range from mild tremors to significant motor and cognitive impairment. Therapy is often supportive.

Prion diseases

Diseases caused by prion infection. Prion diseases affect both animals and humans. Creutzfeldt-Jakob disease (CJD) and variant CJD are discussed in a separate card.


  • Etiology: rapidly lethal prion infection; acquired through ritualistic cannibalism → neuronal loss, gliosis, and spongiform degeneration of the brain gray matter
  • Clinical features
    • Cerebellar ataxia
    • Muscle tremors
    • Pathological laughter
  • Treatment: supportive

Gerstmann-Sträussler-Scheinker syndrome

  • Etiology: rapidly lethal prion infection → deposition of amyloid plaques, mainly in the cerebellum
  • Clinical features
    • Cerebellar ataxia
    • Dysarthria
    • Nystagmus
    • Late-onset dementia
  • Treatment: supportive




Tolosa-Hunt syndrome

  • Etiology: unknown
  • Pathophysiology: granulomatous inflammation in the area of the cavernous sinus or the superior orbital fissure
  • Clinical features
    • Severe retro-ocular pain
    • Eye muscle paresis (ophthalmoplegia)
  • Treatment: prednisone


Empty sella syndrome

  • Etiology: idiopathic
  • Pathophysiology: enlargement or malformation of the sella turcica → compression of the pituitary gland
  • Clinical features
    • Often asymptomatic
    • Some patients may experience chronic headache.
  • Treatment: symptomatic


Vertical gaze palsy


HTLV-1 associated myelopathy