anisocoria
Pronunciation: an-eye-so-CORE-ee-ah
Unequal pupil sizes that may indicate neurological pathology requiring urgent evaluation.
Full Definition
Anisocoria refers to a condition where the pupils are unequal in size, which can be a critical neurological sign in neurocritical care. While mild anisocoria can be physiological in some individuals, acute or pronounced pupillary asymmetry may indicate serious intracranial pathology such as herniation syndromes, third cranial nerve compression, or expanding intracranial masses. The difference in pupil size is typically measured in millimeters, and anisocoria greater than 1mm is generally considered abnormal in acute settings. Assessment includes evaluation of pupillary light reflexes, accommodation responses, and associated neurological signs. Pharmacological causes of anisocoria must also be considered, particularly in the intensive care setting where various medications can affect pupillary responses.
Usage
Usage note: Greek-derived term; avoid confusion with other pupillary abnormalities.
In Context
- "The patient developed acute anisocoria with the right pupil becoming fixed and dilated, suggesting possible herniation." — nursing assessment
- "Anisocoria evaluation includes testing both direct and consensual pupillary light reflexes." — neurological examination guide