Corneal sensitivity testing assesses how well the cornea can detect light touch or other stimuli, reflecting the function of its sensory nerves. Reduced sensitivity can occur in various ocular and systemic conditions.
Methods
Simple approaches use fine cotton strands gently touching the cornea, while specialised instruments such as the Cochet-Bonnet aesthesiometer or non-contact devices deliver calibrated mechanical or air-puff stimuli. Responses are recorded as present, reduced, or absent, and thresholds can be quantified.
- Testing is usually performed at several corneal locations
- Topical anaesthetic must not be used before assessment
- Non-contact methods improve standardisation and patient comfort
- Results can be compared with normative data where available
Clinical Importance
Corneal sensitivity testing is important in diagnosing neurotrophic keratopathy, evaluating post-surgical nerve recovery, and assessing systemic neuropathies such as diabetes. It also informs management of dry eye and contact lens wear.
- Reduced sensation increases risk of corneal injury and poor healing
- Monitoring can show gradual nerve regeneration after procedures
- Guides decisions about protective treatments and lubrication
- Findings are interpreted alongside corneal nerve imaging and surface examination
