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Related Experiment Video

Updated: May 29, 2026

Ex Vivo OCT-Based Multimodal Imaging of Human Donor Eyes for Research into Age-Related Macular Degeneration

Ex Vivo OCT-Based Multimodal Imaging of Human Donor Eyes for Research into Age-Related Macular Degeneration

Published on: May 26, 2023

Foveal phase retardation changes associated with normal aging.

Dean A VanNasdale¹, Ann E Elsner, Timothy Hobbs

¹Indiana University, School of Optometry, Bloomington 47405,USA. dvannasd@indiana.edu

Vision Research

|September 7, 2011

Summary

This summary is machine-generated.

Normal aging causes structural changes in the central macula

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Area of Science:

Ophthalmology
Neuroscience
Biomedical Engineering

Background:

The Henle fiber layer's birefringent properties offer insights into photoreceptor axon structure.
Quantifying age-related changes in the macula is crucial for understanding vision decline.

Purpose of the Study:

To quantify normal age-related structural changes in central macular photoreceptor axons.
To investigate the relationship between age and Henle fiber layer birefringence.

Main Methods:

Used a scanning laser polarimeter to image the macula in 120 healthy individuals (ages 20-80).
Analyzed phase retardation maps using sine curve fitting and Fast Fourier Transform (FFT).
Measured macular phase retardation magnitude and FFT components at varying eccentricities.

Main Results:

Macular phase retardation magnitude (2f amplitude) decreased with age.
Normalized 2f FFT component also decreased with age.
The eccentricity of the maximum normalized 2f FFT component increased with age.

Conclusions:

Age-related changes in the central macula indicate alterations in cone photoreceptor axons.
These structural changes may involve a reduction in cone photoreceptor number or altered axon orientation.
Scanning laser polarimetry effectively demonstrates systematic age-related changes in central cone photoreceptor morphology.