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Neuro-Ophthalmic

Physiologic Anisocoria

Also known as: physiologic anisocoria, physiological anisocoria, benign anisocoria, longstanding anisocoria, old photos anisocoria

Filed as: Routine

Source-cited from the record's own evidence list. Clinical content programme led by Dr Ankit Mathur, PhD, Grad Cert Ocu Thera, B.S. Optom. How the clinical content is governed

Overview

A benign difference in pupil size, usually under a millimetre, present in a substantial minority of people and stable across years. The difference stays proportionally similar in bright and dim light, both pupils react normally, and old photographs typically show the same pattern. That stability, and the symmetry of the light reaction, are what distinguish it from a newly acquired difference, which is assessed rather than assumed benign.

Recognition

Symptoms: what patients report

  • Usually asymptomatic incidental anisocoria.
  • Longstanding history or old photos showing the same pattern.

Signs: what the examination shows

  • Typically less than 1 mm difference.
  • Stable across time.
  • Not notably different in bright or dim lighting.
  • Normal iris appearance.
  • No ptosis, diplopia, motility restriction, pain, red eye, or neurological features.

What OptoGuide™ covers for physiologic anisocoria

  • Pattern reasoning: what this combination of findings points to, and its differentiators
  • Don't-miss risks and escalation triggers
  • Management tiers with linked Australian therapeutics
  • Referral urgency, specialty, and letter drafting

Sources

Standard texts: Kanski's Clinical Ophthalmology: A Systematic Approach, Oxford Handbook of Ophthalmology, Oxford American Handbook of Ophthalmology, Signs in Ophthalmology: Causes & Differential Diagnosis.

Full bibliography

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