Wide-field individual retinal layer thickness in healthy eyes

Area of Science:

• Ophthalmology
• Medical Imaging
• Retinal Imaging

Background:

• Accurate measurement of retinal layer thickness is crucial for diagnosing and monitoring various eye conditions.
• Wide-field optical coherence tomography (WF-OCT) offers enhanced visualization of the entire retina, including peripheral areas.

Purpose of the Study:

• To quantify individual retinal layer thicknesses in healthy subjects using WF-OCT.
• To analyze regional variations in retinal thickness across different meridians and segments.
• To identify factors, such as age, influencing retinal layer thickness.

Main Methods:

• Prospective, cross-sectional study of healthy subjects.
• Utilized a custom semi-automated segmentation algorithm for retinal layer analysis.
• Measured individual retinal layer thicknesses in horizontal and vertical meridians, analyzing variations at 1mm intervals.

Main Results:

• Analyzed 20 eyes from 20 healthy subjects (mean age 28.9 years).
• Nasal and superior segments showed maximum and minimum overall retinal thicknesses, respectively.
• Significant variations in Outer Plexiform Layer, External Limiting Membrane-Ellipsoid Zone, and Interdigitation Zone-Retinal Pigment Epithelium-Bruch's Complex were observed (p<0.05).
• The macular segment exhibited the highest coefficient of variation.
• Age was the only significant factor affecting retinal thickness (p=0.001).

Conclusions:

• WF-OCT demonstrates substantial regional variability in both overall and individual retinal layer thicknesses in healthy eyes.
• The macular segment shows the highest degree of variation in retinal thickness.
• Findings highlight the importance of considering regional differences and age in retinal imaging analysis.