anisocoria
Pronunciation: /ˌænɪsoʊˈkɔriə/
Unequal pupil sizes between the two eyes, which may be physiologic or pathologic.
Full Definition
Anisocoria refers to a difference in pupil diameter between the two eyes, with the disparity typically measured in bright and dim lighting conditions. Physiologic anisocoria (present in 10-20% of the population) shows minimal difference that remains constant in varying light conditions. Pathologic anisocoria may indicate serious neurological conditions affecting the sympathetic or parasympathetic pupillary pathways, including Horner's syndrome, third cranial nerve palsy, Adie's tonic pupil, or pharmacologic mydriasis. The pattern of anisocoria in light versus dark conditions helps determine which pupil is abnormal and guides diagnostic evaluation.
Usage
Usage note: Document measurements in both light and dark conditions; note onset timing if acute.
In Context
- "The patient presented with acute-onset anisocoria following head trauma." — Emergency department note
- "Pharmacologic testing confirmed Horner's syndrome as the cause of anisocoria." — Diagnostic workup