Station 02 — Visual Acuity Examination
🎯 Candidate Task
Assess the patient’s distance visual acuity in each eye separately using the provided visual-acuity chart. Record your findings correctly and perform pinhole testing if indicated.
⚡ Model Station Answer
- I assessed each eye separately at the correct chart distance, using the patient’s usual distance correction where appropriate.
- I would record the acuity for each eye separately, for example Right eye 6/6, Left eye 6/12.
- If acuity is reduced, I would repeat testing through a pinhole.
- Improvement with pinhole suggests that a refractive component is contributing to the reduced visual acuity.
🔎 How to Perform / Approach
- Prepare: Perform hand hygiene, introduce yourself, confirm the patient, explain the test and obtain consent.
- Position correctly: Seat or stand the patient 6 metres from a well-illuminated Snellen chart positioned approximately at eye level.
- Check correction: Ask whether the patient normally wears distance glasses; test with their usual distance correction when appropriate.
- Test one eye: Ask the patient to cover one eye without pressing on it and read the smallest line they can identify accurately.
- Record the result: Record the tested eye separately as a Snellen fraction such as 6/6, 6/9 or 6/12, and note whether it was unaided or with glasses.
- Repeat: Test the opposite eye using the same method.
- Use pinhole if reduced: Repeat the reduced eye through a pinhole and document the new acuity. Improvement supports a refractive cause; absent significant improvement requires further ocular assessment.
🖼️ Visual Learning
Visual Acuity Examination — Snellen Testing and Pinhole

🎥 Practical Demonstration
Ophthalmology Department, Cairo University — practical undergraduate demonstration of visual-acuity assessment.
📝 Important Viva Questions
1. What does a visual acuity of 6/12 mean?
Answer: The patient can read at 6 metres what a person with standard visual acuity can read at 12 metres.
2. Why should each eye be tested separately?
Answer: Testing each eye independently detects unilateral or asymmetrical reduction in visual acuity that binocular testing may conceal.
3. When should a pinhole be used?
Answer: Pinhole testing is used when distance visual acuity is reduced to determine whether a refractive component is contributing.
4. What does improvement in visual acuity with a pinhole suggest?
Answer: Significant improvement suggests that the reduced acuity is at least partly due to refractive error.
5. How should visual acuity be documented?
Answer: Record each eye separately using the Snellen fraction and indicate whether testing was unaided, with spectacles or through a pinhole.
