Horner's Syndrome Underlying Cause
Horner's syndrome is usually caused by irritation of nerves in the neck that supply the face.
Common causes include:
- Inflammation of structures within the neck
- Localized swelling causes pressure on a nerve
- Lung cancer
- The tumor is pressing on a nerve
- Carotid artery aneurysm
- Weak and swollen area of the carotid artery that is pressing on a nerve
- Subclavian artery aneurysm
- Weak and swollen area of the subclavian artery that is pressing on a nerve
- Carotid artery dissection
- Neck injury:
- Injury to a nerve
- Cluster headaches
- Carotid artery occlusion
- A disorder where a cyst forms within the spinal cord.
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- Patel S, Ilsen PF. Acquired Horner's syndrome: clinical review. Optometry. 2003 Apr;74(4):245-56.