Horner's Syndrome

Horner's syndrome is the classic triad of:
  • ptosis
  • miosis
  • anhydrosis

Causes include:
  • stroke
  • lateral medullary syndrome (Wallenberg syndrome)
  • syrinx
  • carotid dissection or aneurysm
  • MS
  • Pancost tumour
  • trauma


Treatment depends on the cause.


Topical cocaine can be used to confirm Horner's syndrome; normal pupils dilate in response to topical cocaine while in Horner's they do not.


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Sarah Hudson

Secret collector of interesting anonymised ECGs. Fan of the Bath Photomarathon. Lover of cream teas.

Secret collector of interesting anonymised ECGs. Fan of the Bath Photomarathon. Lover of cream teas. [Sarah Hudson] (Your Picture)