Answer
Specialist examinations assess corneal crystal deposits, symptoms such as photophobia and possible corneal irritation from the preservative.
Sources for this answer
- Cystadrops 3.8mg/ml eye drops — Current selected SmPCemc · Summary of Product Characteristics
- NHSNHS · NHS medicine guidance
General medicine information. Follow the instructions for your own medicine and speak to a pharmacist or clinician about your individual circumstances.