Sudden vision loss — differential and referral priorities

Structured for Australian optometry practice.

Quick answer

  • Triage sudden vision loss first by onset, laterality, pain, and whether the reduction is monocular or binocular.
  • Retinal detachment, vascular occlusion, vitreous haemorrhage, optic neuritis, and acute glaucoma should be separated early.
  • Check acuity, pupils, fields, anterior segment findings, and retinal status where possible.
  • Same-day escalation is appropriate when vision loss is new, unexplained, or associated with RAPD, field loss, pain, or retinal signs.

Common causes

  • Retinal detachment or retinal tear with macular involvement.
  • Retinal vascular occlusion.
  • Vitreous haemorrhage.
  • Optic neuritis or other optic neuropathy.
  • Acute angle closure or severe anterior segment disease.

Red flags (must not miss)

  • New RAPD, marked acuity drop, or colour desaturation.
  • Curtain, field defect, or fundus signs of detachment.
  • Cherry-red spot, retinal whitening, or vascular asymmetry.
  • Painful vision loss or associated headache, nausea, or photophobia.
  • Unexplained sudden loss with limited posterior view.

Use OptoGuide™ to guide this decision during consult.

What to check

  • Clarify exact onset, progression, pain, and monocular versus binocular pattern.
  • Measure acuity, pupils, colour comparison, and confrontation fields.
  • Assess IOP and anterior chamber if angle closure is possible.
  • Dilated fundus examination for haemorrhage, detachment, oedema, or pallor.
  • Document whether the posterior view is complete or obstructed.

When to refer

  • Same day for unexplained sudden monocular vision loss.
  • Urgent ophthalmology or emergency review for retinal, vascular, or acute glaucoma suspicion.
  • Escalate immediately when the optic nerve or retina appears acutely compromised.

Initial management

  • Treat sudden vision loss as time-sensitive until a benign explanation is clear.
  • Record acuity, pupils, field findings, and key fundus observations before referral.
  • Avoid reassuring a new sudden loss without a complete explanation and exam.

Clinical basis

This guidance reflects standard optometric clinical reasoning based on:

  • Australian optometry clinical practice patterns
  • Australian medicines regulation and PBS prescribing context
  • Common ophthalmology referral standards
  • Evidence-based clinical training and practice
View full clinical basis

Use OptoGuide™ during consult for structured clinical guidance.

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