[Morphometric OCT parameters of the lens under accommodative stimulus. Report 1. Assessment of age-related changes].

Under accommodative stimulus, statistically significant changes occurred in multiple lens morphometric parameters across the entire cohort.

• Study included 74 healthy volunteers (123 eyes) aged 20-85 years.
• Decrease in radius of curvature of the anterior lens surface (p=0.003) and posterior lens surface (p=0.045) under accommodative stimulus.
• Increase in lens thickness (p=0.011) and nuclear thickness (p=0.007) under accommodative stimulus.
• Reduction in lens diameter (p=0.026) and anterior chamber depth (p=0.033) under accommodative stimulus.
• Accommodative stimulus was induced using a -5.0 D negative spherical lens with a radial fixation target integrated into the CASIA2 OCT optical system.

The radius of curvature of the anterior lens surface at relative accommodative rest was significantly higher in the youngest age group (20-30 years) compared to older groups.

• Three age groups were formed: 20-30 years (43 observations), 31-50 years (33 observations), and >51 years (47 observations).
• Median anterior lens surface radius of curvature values were 11.62 mm, 9.47 mm, and 9.25 mm for groups 1, 2, and 3, respectively.
• The difference between group 1 and groups 2 and 3 was statistically significant (p=0.00).
• The magnitude of changes in lens curvature radius under accommodative stimulus significantly decreased with increasing age for both anterior and posterior surfaces.

Statistically significant correlations with age were found for the radius of curvature of both lens surfaces and lens thickness.

• Radius of curvature of the anterior lens surface: r=-0.371, p=0.00 (negative correlation with age).
• Radius of curvature of the posterior lens surface: r=-0.224, p=0.013 (negative correlation with age).
• Lens thickness: r=0.268, p=0.003 (positive correlation with age).
• These correlations were derived from analysis of changes induced by accommodative stimulus across the full cohort (n=123).

Baseline lens thickness and nuclear thickness increased significantly with age and also demonstrated an increase under accommodative stimulus across all age groups.

• Both baseline lens thickness and nuclear thickness showed statistically significant age-related increases.
• Lens thickness and nuclear thickness increased under accommodative stimulus in all three age groups (20-30, 31-50, and >51 years).
• This pattern was observed regardless of age group.

The CASIA2 SS AS-OCT device was found to be a highly informative method for assessing morphometric parameters of the crystalline lens under both relative accommodative rest and lens-induced accommodative stress.

• The device enabled near-screening evaluation of lens shape and position at baseline and under accommodative stimulus.
• The integrated optical system provides lens-induced accommodative stress directly in the examined eye using a -5.0 D negative spherical lens.
• The system uses a fixation target in the form of a radial figure integrated into the optical system of the CASIA2 OCT device.