Eye Assessment & Visual Acuity
Establish a reliable visual baseline and recognise findings that need urgent eye care.
Quick revision ↓ Medical Dictionary
01Start with urgency
Ask whether visual change was sudden or gradual, painful or painless, and involved one or both eyes. Establish the last time vision was normal. Trauma, chemical exposure, severe pain, photophobia and new field loss alter urgency. Do not let a lengthy routine history delay emergency treatment or referral when sight is threatened.
02Measure each eye
Measure distance acuity separately with the usual distance correction, using the chart at its calibrated distance. Record the chart and result for each eye. If standard letters cannot be read, document progressively simpler measures such as counting fingers or light perception. Poor acuity is a finding requiring explanation rather than a diagnosis by itself.
03Use pinhole thoughtfully
Pinhole improvement suggests a refractive contribution, but does not prove the eye is otherwise healthy. Lack of improvement may reflect retinal, optic nerve or media disease, or difficulty using the test. Compare near vision where relevant. Relate measurements to previous acuity, symptoms and the rest of the examination instead of relying on one result.
04Examine systematically
Inspect lids and alignment, assess pupils before dilation, and evaluate movements, fields and the anterior eye as appropriate. Fundus examination requires adequate equipment and skill. Record when a structure could not be assessed rather than calling it normal. Avoid pressure or tonometry if an open-globe injury is suspected and obtain emergency ophthalmic assistance.
05Communicate the findings
A useful referral states onset, laterality, acuity in both eyes, pain, relevant pupil or field findings, trauma and medicines. State the clinical concern and confirm the receiving pathway. Explain urgency and practical travel needs. If follow-up is arranged, document who will review the patient and which deterioration requires immediate return.
High-Yield Revision
- Record acuity separately for each eye.
- Pinhole improvement suggests a refractive component.
- Document examination limitations explicitly.
Common Pitfalls
- Calling an unexamined fundus normal.
- Letting a routine examination delay emergency referral.
References & Further Reading
Read the relevant guideline sections alongside these original clinical teaching cases. Local pathways, available services and individual patient factors determine care.
Reference review: 28 September 2026. Consult current local protocols for prescribing, procedures and escalation.