HORNER'S SYNDROME
Richard S. Krause
BASICS
DESCRIPTION
Unilateral sympathetic denervation of the eye produces signs of Horner's syndrome:
- Relaxation of retracting muscles in upper and lower lids:
- Ptosis
(drooping of the lids)
- Loss of pupillary dilator innervation:
- Miosis
(unopposed pupillary constriction)
- Loss of sympathetic stimulation of sweat glands:
ETIOLOGY
- 40% unknown (in 1 large series)
- Tumors of lung or metastases to cervical nodes:
- May interrupt preganglionic sympathetic fibers (between thoracic sympathetic trunk and superior cervical ganglion)
- Trauma: Penetrating neck wounds directly injure sympathetic fibers
- Pneumothorax:
- Tension pneumothorax may cause traction on sympathetic fibers owing to shift of mediastinal structures.
- Infiltration or infection of cervical nodes:
- Sarcoidosis, tuberculosis
- Vascular disorders:
- Migraine or cluster headaches
- Carotid artery dissection
- Lateral medullary infarction produces Horner's syndrome as part of the Wallenberg syndrome:
- Presents with vertigo and ataxia, which may overshadow the Horner's syndrome.
- Cavernous sinus thrombosis may present with some of the features of Horner's syndrome:
- The condition typically causes headache and/or eye pain.
- Ocular signs include ocular palsies, pain, chemosis, and proptosis.
Pediatric Considerations
- Hereditary Horner's syndrome:
- Blue iris (or irregular coloration) on affected side
- Brown on unaffected side (heterochromia iridis)
- Birth trauma:
- May cause damage to sympathetic chain
- New Horner's syndrome in a child should prompt workup for tumor (neuroblastoma).
DIAGNOSIS
SIGNS AND SYMPTOMS
- Horner's syndrome is characterized by:
- Ptosis:
Drooping of eyelid on affected side, usually slight
- Miosis:
Decrease in pupillary size on involved side (pupillary asymmetry ≥1 mm)
- Anhidrosis:
Lack of sweating on involved side of face
- The importance of Horner's syndrome is its association with certain disease states.
History
Focus on pre-existing conditions that predispose to Horner's syndrome or are risk factors for these conditions:
- Tumors, vascular disease, trauma:
- Minor trauma often precedes carotid dissection.
- Cardiovascular risks
- Exposures:
- Pain:
- Suggests carotid dissection
ALERT
- Acute Horner's syndrome with neck or facial pain:
- Presume carotid dissection until proven otherwise:
- 50% of internal carotid artery dissections present with a painful Horner's syndrome.
Physical-Exam
Concentrate on a focused neurologic exam looking to confirm Horner's syndrome and exclude other neurologic deficits:
- General physical exam should focus on identifying signs of other suspected conditions, such as tumor.
ESSENTIAL WORKUP
- History and physical exam focused on neurologic findings
- CXR to screen for tumor or pneumothorax
DIAGNOSIS TESTS & NTERPRETATION
Provocative testing:
- Pharmacologic (cocaine) testing confirms diagnosis of sympathetic ocular lesion:
- 1 drop of 5% ocular cocaine solution is instilled
into each eye
.
- Failure of pupil on involved side to dilate as much as other pupil (increase in amount of anisocoria) in 1 hr is confirmatory (positive test).
Lab
Not useful for Horner per se:
- Often needed as part of the workup of causative or associated conditions.
Imaging
- CXR is usually indicated because of the association of chest pathology and Horner's syndrome.
- CT or MRI of head, neck, or chest may be indicated depending on signs and symptoms.
- For suspected carotid dissection:
- MRA or CTA of the head and neck:
- Either test is appropriate
- The lesion is expected to be ipsilateral to the Horner's syndrome.
- Choice of neuroimaging in suspected stroke depends heavily on local protocols and resources.
- At a minimum, if stroke is suspected CT of the brain is indicated to rule out hemorrhagic stroke.
- If acute stroke (<3 hr) is suspected and patient is a candidate for thrombolysis image on STAT basis
Diagnostic Procedures/Surgery
Ocular tonometry is indicated if acute glaucoma is suspected.
DIFFERENTIAL DIAGNOSIS
- Increased intracranial pressure (ICP):
- Almost always associated with altered level of consciousness (LOC), headache
- Simple anisocoria (pseudo-Horner's syndrome):
- 15–20% of the population has anisocoria and 3–4% also has miosis and ptosis.
- Cocaine test is negative (both pupils dilate equally).
- Inspect photo ID for pre-existing anisocoria.
- Topical medications or exposures are a common cause of miosis.
- Migraine or cluster headache
- Glaucoma, inflammatory ocular diseases, or ocular trauma
TREATMENT
PRE HOSPITAL
Cautions:
- The importance of Horner's syndrome is its association with more serious underlying conditions.
- Patients with increased ICP or tension pneumothorax must be recognized and treated as soon as possible.
- If acute stroke suspected transport to designated stroke center when possible
INITIAL STABILIZATION/THERAPY
- If increased ICP is suspected, initiate measures to control ICP:
- Intubation, osmotic diuretics
- Tension pneumothorax:
- Needle thoracostomy followed by chest tube
ED TREATMENT/PROCEDURES
Horner's syndrome per se requires no ED treatment:
- Causative or associated conditions may require treatment.
MEDICATION
Cocaine: 5% (adult), 2.5% (peds) ophthalmic solution: 1 drop in each eye is diagnostic.
FOLLOW-UP
DISPOSITION
Admission Criteria
Admission for isolated Horner's syndrome is not needed:
- Admission may be needed for underlying condition.
Discharge Criteria
- Stable patients with isolated Horner's syndrome may be discharged with appropriate follow-up arranged for continued workup as outpatient:
- When Horner's syndrome is suspected, emergencies such as carotid dissection or stroke should be ruled out prior to discharge.
FOLLOW-UP RECOMMENDATIONS
Neurologists and ophthalmologists must often be involved in the workup of Horner's syndrome.
PEARLS AND PITFALLS
Must consider underlying etiology
ADDITIONAL READING
- Debette S, Leys D. Cervical-artery dissections: Predisposing factors, diagnosis, and outcome.
Lancet Neurol
. 2009;8(7):668–678.
- Maloney WF, Younge BR, Moyer NJ. Evaluation of the causes and accuracy of pharmacologic localization in Horner’s syndrome.
Am J Ophthalmol
. 1980;90(3):394–402.
- Martin TJ. Horner’s syndrome, Pseudo-Horner’s syndrome, and simple anisocoria.
Curr Neurol Neurosci Rep
. 2007;7(5):397–406
- Proctor C, Chavis PS. Horner's syndrome.
J Neuroophthalmol.
2013;33(1):88–89
- Thanvi B, Munshi SK, Dawson SL, et al. Carotid and vertebral artery dissection syndromes.
Postgrad Med
. 2005;81:383–388.
- Wilheim H, Ochsner H, Kopycziok E, et al. Horner’s syndrome: A retrospective analysis of 90 cases and recommendations for clinical handling.
Ger J Ophthalmol
. 1992;1(2):96–102.
CODES