Single dispersive gradient-index profile for the aging human lens.

Area of Science:

• Ophthalmology
• Biomedical Optics
• Computational Biology

Background:

• Human eye aging affects optical properties, including crystalline lens refractive index.
• Age-related changes impact visual functions like spherical aberration and image quality.
• Existing models often lack detailed, age-dependent crystalline lens profiles.

Purpose of the Study:

• To develop an updated age-dependent emmetropic-eye model.
• To incorporate a single gradient-index (GRIN) profile for the crystalline lens.
• To account for age-related variations in refractive index, spherical aberration, and image quality.

Main Methods:

• Developed a novel age-dependent gradient-index (GRIN) profile for the crystalline lens.
• Analyzed the variation of GRIN parameters with age.
• Incorporated refractive index dispersion to model ocular optical properties.

Main Results:

• Dispersion parameters of the refractive index were found to be invariant with age.
• Parameters defining lens index distribution showed a slight decrease in lens-center-index value with age.
• The position of the lens-center-index along the lens axis changes with age.

Conclusions:

• The developed GRIN profile accurately models age-related changes in the crystalline lens.
• Findings support the lens paradox, explaining how lens properties change with aging.
• The model provides a foundation for understanding age-related visual decline and developing corrective strategies.