The conjunctival sensitivity in soft contact lens wearers

Area of Science:

• Ophthalmology
• Optometry
• Corneal Physiology

Background:

• Soft contact lenses (SCLs) are widely used for vision correction.
• Some SCL users report dry eye symptoms, even without a diagnosis of dry eye disease.
• The impact of SCL wear on ocular surface sensitivity is not fully understood.

Purpose of the Study:

• To investigate the effect of SCL wear on conjunctival sensitivity.
• To determine if SCL use alters corneal touch thresholds.
• To explore the potential link between altered sensitivity and dry eye symptoms in SCL wearers.

Main Methods:

• A study involving 26 volunteers without dry eye was conducted.
• Participants were divided into SCL wearers (n=12) and non-wearers (n=14).
• Conjunctival sensitivity was measured using a Cochet-Bonnet esthesiometer, with results converted to tension (g/mm²).

Main Results:

• SCL wearers exhibited significantly lower mean touch thresholds compared to non-wearers.
• This difference was observed in both the whole conjunctiva and the upper palpebral conjunctiva (p < 0.01).
• Mean thresholds for SCL wearers were 10.7 g/mm² (whole) and 9.07 g/mm² (upper palpebral).

Conclusions:

• SCL wear is associated with enhanced conjunctival sensitivity.
• Increased sensitivity may contribute to the development of dry eye-like symptoms in individuals wearing SCLs.
• Further research is warranted to understand the clinical implications of this finding.