Station 18 — Cataract Examination and Recognition
Rapid Revision • Practical Skills • Viva
🎯 Candidate Task
Perform a focused ocular assessment of this patient, paying particular attention to the red reflex and lens appearance. Describe your findings and identify the abnormality shown in the adult and paediatric clinical images provided.
⚡ Model Station Answer
- I would assess visual acuity and compare both eyes.
- The affected eye shows a reduced or absent red reflex with visible opacity of the normally transparent lens.
- A normal clear lens permits a bright, symmetrical red reflex; a cataractous lens appears grey-white or opaque and interferes with the reflex.
- These findings are consistent with cataract. Similar lens opacity or an abnormal/white pupillary reflex in a child may represent congenital cataract.
🔎 How to Perform / Approach
🖼️ Visual Learning
Clear Lens versus Adult and Congenital Cataract

📝 Important Viva Questions
1. What is a cataract?
Answer: A cataract is an opacity of the crystalline lens that reduces its transparency.
2. What happens to the red reflex in a significant cataract?
Answer: The red reflex becomes reduced, irregular or absent because the lens opacity blocks the passage of light.
3. How does a normal lens differ from a cataractous lens on examination?
Answer: A normal lens is transparent with a preserved red reflex, whereas a cataractous lens shows visible opacity and impaired red reflex.
4. Which instrument is useful for detailed examination of lens opacity?
Answer: A slit-lamp biomicroscope allows magnified examination of the lens and localization of the opacity.
5. Why is congenital cataract clinically important?
Answer: Significant congenital cataract can obstruct visual development and lead to amblyopia if not recognized early.
