sympathetic
Sympathetic Nervous System
Plain-language definition
Part of the autonomic nervous system controlling fight-or-flight responses. Disruption of the sympathetic pathway to the eye causes Horner syndrome.
Where this term comes up
“Horner syndrome is a combination of signs caused by damage to the sympathetic nerve pathway, the nerves that control pupil dilation, eyelid elevation, and facial sweating.”
Condition · Horner Syndrome
“Sympathetic nerves: dilate the pupil”
Symptom · Unequal Pupil Size (Anisocoria)
“A doctor can localize a problem to the optic nerve, brainstem, sympathetic chain, or parasympathetic pathway - all by observing how your pupils react to light and near focus.”
Test · Pupil Examination
- Category
- Clinical term
- Also written as
- No alternate forms listed.
Clinical terms are words clinicians use to describe symptoms, signs, risk factors, or patterns seen during evaluation.
Related glossary terms
- aneurysm
Vessel Bulge
- MRI
Magnetic Resonance Imaging
- apraclonidine
Alpha-Agonist Eye Drop
- ptosis
Drooping Upper Eyelid
- anisocoria
Pupils of Unequal Size
- bilaterally
On Both Sides
A note on medical context
A glossary definition can explain a word, but it cannot tell you whether a symptom or test result is serious. If this term came from an article, use the full article and your clinician's guidance for context.