Rigid gas-permeable extended wear: a comparative clinical study

Area of Science:

• Ophthalmology
• Optometry
• Corneal Physiology

Background:

• Extended wear contact lenses offer convenience but pose risks to ocular health.
• Comparing rigid gas-permeable (RGP) and soft contact lenses for extended wear is crucial for patient safety and visual outcomes.
• Understanding lens-related complications and physiological changes is vital for clinical management.

Purpose of the Study:

• To compare the clinical performance of rigid gas-permeable lens extended wear (EWRGP) with daily wear RGP (DWRGP) and soft lens extended wear (SLEW).
• To evaluate adverse effects on corneal physiology and refractive error changes over a 12-month period.
• To identify factors influencing lens wear complications and inform clinical management strategies.

Main Methods:

• A 12-month prospective clinical trial involving 88 subjects.
• Comparison of EWRGP, DWRGP, and SLEW (medium water content) contact lenses.
• Monitoring of refractive error, corneal curvature, corneal distortion, edema, staining, and slit-lamp findings.

Main Results:

• EWRGP withdrawals were primarily lens-related; SLEW withdrawals were due to corneal physiological issues.
• Significant myopia increase (0.38 D) observed in 58% of SLEW wearers, unlike EWRGP.
• EWRGP group showed mean corneal flattening and increased corneal distortion (69%) compared to DWRGP (30%) and SLEW (17%), likely due to corneal edema and molding.

Conclusions:

• Rigid gas-permeable lens extended wear is associated with higher rates of corneal distortion and lens-related issues.
• Soft lens extended wear may lead to myopia progression and adverse corneal physiological effects.
• Careful patient selection and monitoring are essential for managing extended wear contact lenses, particularly RGP lenses.