neurologic disorders
Horner Syndrome
Key Points
Horner syndrome causes ptosis, miosis, and anhidrosis. It results from a central or peripheral lesion (preganglionic or postganglionic) that disrupts the cervical sympathetic pathway, which runs from the hypothalamus to the eye. Instillcocaine,apraclonidine, and/or hydroxyamphetamine in both eyes to confirm the diagnosis of Horner syndrome and help locate the lesion (preganglionic or postganglionic). Do MRI or CT of the brain, spinal cord, chest, or neck, depending on clinical suspicion. Treat the cause, if identified; there is no treatment for primary Horner syndrome. 