Horner Syndrome

Snapshot

• A 67-year-old man presents to his physician following a right-sided carotid endarterectomy. He reports mild pain at the surgical site but currently does not have any concerns. On physical exam, there is anisocoria with the right eye being miotic. There is also mild ptosis on the right eye as well.

Introduction

• Clinical definition
  • a neurologic syndrome characterized by ipsilateral
    • miosis
    • ptosis
    • anhidrosis
• Pathogenesis 
  • can be caused by a lesion anywhere on the sympathetic pathway supplying the 
    • head, eyes, and neck
      • review the sympathetic course in this illustration 
  • causes include
    • Pancoast tumor 
    • Wallenberg syndrome
    • syringomyelia and cervical cord trauma that affects the
      • intermediolateral columns
    • carotid endarterectomy and carotid artery stenting
• carotid dissection

Presentation

• Symptoms and physical exam 
  • miosis
    • resulting in anisocoria
    • secondary to unchecked parasympathetic innervation
  • ptosis
    • due to impaired sympathetic innervation to Muller’s muscle
    • generally mild
  • anhidrosis
    • suggests an central or preganglionic lesion