Horner's (Bernard-Horner's) syndrome

Etiology

• lung carcinoma (non small-cell carcinoma)
  • onset may be gradual
• internal carotid artery dissection (generally acute onset)

Pathology

• Horner's syndrome occurs secondary to a lesion in the cervical sympathetic chain
  • disruption of the sympathetic pathways to the eye
• often in association with a Pancoast tumor involving both upper & lower brachial plexus, or its central pathways

Clinical manifestations

• ipsilateral ptosis, miosis, & anhidrosis (on the side of the sympathetic palsy)
• enophthalmos may be apparent
• the affected pupil is slow to dilate (anisocoria) in dim light
• headache
• contralateral upper extremity & facial weakness (carotid artery dissection)
• shoulder pain, shoulder & arm weakness (brachial plexopathy)*

* Pancoast syndrome

Radiology

• magnetic resonance angiography needed to rule-out carotid artery dissection

More general terms

• syndrome

Additional terms

• Pancoast tumor (superior pulmonary sulcus tumor)