Horner Syndrome


Horner syndrome is associated with an interruption to the sympathetic nerve supply of the eye. It is characterized by the classic triad of miosis, partial ptosis, and anhidrosis +/- enophthalmos

Horner Syndrome may occur secondary to:

  • Local compression of brachial plexus and sympathetic chain by superior (pulmonary) sulcus tumors.(e.g. Pancoast tumor)
  • Brainstem stroke
  • Carotid artery aneurysm (dissection) or critical ischaemia
  • Trauma involving the brachial plexus
  • Neoplasm of the middle cranial fossa
Horner left ptosis miosis no flash

History of Horner Syndrome

1869 –  Johann Friedrich Horner (1831-1886) reported the findings of ptosismiosis, and enophthalmos in a 40-year-old peasant woman. He also observed increased skin temperature and dryness of the ipsilateral face.

He pharmacologically confirmed the impairment of sympathetic innervation to the eye after noting poor dilation of the affected pupil following instillation of atropine and preserved pupillary constriction to the parasympathomimetic agent calabar. [1869;7:193-198]

Associated Persons

Alternative names
  • Horner’s syndrome
  • Bernard-Horner syndrome (France)
  • Claude Bernard syndrome
  • Von Passow syndrome


eponymictionary CTA


the names behind the name

Emergency physician MA (Oxon) MBChB (Edin) FACEM FFSEM with a passion for rugby; medical history; medical education; and asynchronous learning #FOAMed evangelist. Co-founder and CTO of Life in the Fast lane | Eponyms | Books |

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