Tear Dynamics During Fenestrated Scleral Lens Wear: A Pilot Study

Area of Science:

• Ophthalmology
• Biomedical Engineering
• Contact Lens Technology

Background:

• Scleral lenses create a fluid reservoir between the lens and cornea.
• Understanding tear dynamics within this reservoir is crucial for optimizing lens design and patient outcomes.
• Current methods for assessing tear exchange are limited.

Purpose of the Study:

• To develop and validate a Scheimpflug-based image analysis technique for quantifying tear exchange.
• To investigate tear fluid reservoir dynamics in fenestrated scleral lens wear.

Main Methods:

• Nine healthy participants wore a fenestrated scleral lens for 90 minutes.
• Scheimpflug images were captured after sodium fluorescein application to assess tear mixing.
• Corneal edema was measured using optical coherence tomography.

Main Results:

• The developed technique showed good repeatability for measuring fluid reservoir intensity.
• Tear fluid intensity varied spatially, being higher in the periphery.
• Two distinct tear dynamics patterns (low and high flow) were observed.
• Low flow was associated with increased corneal edema, though not statistically significant.

Conclusions:

• Tear exchange in fenestrated scleral lenses stabilizes within 10 minutes.
• The study identified two tear flow patterns, suggesting implications for corneal health.
• The developed Scheimpflug imaging technique offers a novel approach for studying tear dynamics in scleral lens wear.