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Intermediate Technical IVT

anisocoria

Pronunciation: an-eye-so-KOR-ee-uh

Unequal pupil sizes, which may indicate neurological pathology or be a benign variant.

Full Definition

Anisocoria describes the condition where pupils are of unequal size, with a difference typically greater than 0.4mm being considered significant. This finding may be physiological (occurring in approximately 20% of the population) or pathological, potentially indicating cranial nerve III palsy, Horner's syndrome, or increased intracranial pressure. In neurological documentation, the degree of anisocoria and its response to light must be carefully recorded. Editorial precision is crucial as this finding often triggers urgent neurological evaluation.

Usage

Usage note: Distinguish from isocoria (equal pupils) and specify measurement differences in documentation.

In Context

  • "Physical examination revealed 2mm anisocoria with the right pupil larger than the left." — Emergency department note
  • "The anisocoria was more pronounced in bright light, suggesting a parasympathetic lesion." — Ophthalmology consultation

Also known as

pupillary asymmetry

Contrasted with

isocoria

Don't confuse with

mydriasis miosis isocoria

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