Peripheral Contrast Reduction Optically Induced by Scattering Lenses Thickens Peripheral Choroid

Area of Science:

• Ophthalmology
• Optometry
• Vision Science

Background:

• Myopia control strategies, particularly those using scattering lenses, lack clear mechanistic understanding.
• Choroidal thickness and axial length are crucial biomarkers for monitoring myopia progression.

Purpose of the Study:

• To investigate the short-term effects of different scattering lens conditions on central and peripheral choroidal thickness and axial length.
• To elucidate the mechanisms underlying myopia control strategies involving scattering lenses.

Main Methods:

• Twenty-three participants were exposed to five lens conditions for 60 minutes each: medium peripheral scattering, high peripheral scattering, medium full-field scattering, high full-field scattering, and a control (clear lens).
• Central and peripheral choroidal thickness, foveal axial length, and visual acuity were measured pre- and post-lens wear.

Main Results:

• Medium peripheral scattering lenses induced significant peripheral choroidal thickening, particularly in the superior retina, compared to control lenses.
• Medium full-field scattering lenses caused significant nasal central choroidal thickening.
• High scattering conditions (peripheral and full-field) and axial length measurements showed no significant changes. Visual acuity decreased with full-field scattering lenses.

Conclusions:

• A local retinal contrast detection mechanism may signal the choroid to thicken peripherally in response to medium peripheral scattering.
• The level of contrast reduction and the involvement of the peripheral retina are critical factors in myopia research.
• Findings provide insights into the mechanisms of myopia control strategies employing peripheral scattering effects.