Quantifying retinal size and shape distortion in different ultra-widefield imaging systems.

Area of Science:

• Ophthalmology
• Medical Imaging
• Optical Engineering

Background:

• Ultra-widefield (UWF) imaging systems are crucial for visualizing the peripheral retina.
• Accurate assessment of retinal size and shape is vital for diagnosing and monitoring various ocular conditions.
• Understanding distortion in UWF imaging is essential for reliable quantitative analysis.

Purpose of the Study:

• To quantitatively evaluate and compare retinal size and shape distortion across multiple UWF imaging devices.
• To identify factors influencing size distortion, such as eccentricity and axial length.
• To determine which UWF systems exhibit shape distortion.

Main Methods:

• Posterior segments of model eyes were imaged using six different UWF systems (Daytona, Mirante, CLARUS 500, VG2001, BMizar, TRC-NW8).
• Scale bars and ring compactness were measured to quantify size and shape distortion.
• Multivariate linear regression and quadratic polynomial equations were used to analyze relationships between distortion, eccentricity, and axial length.

Main Results:

• Retinal size distortion was positively associated with eccentricity and negatively with axial length across all systems.
• Mirante demonstrated significantly lower size distortion compared to most other systems, except TRC-NW8.
• Daytona was the only system to exhibit shape distortion, with significantly lower compactness than others.

Conclusions:

• Quantitative analysis revealed distinct patterns of size distortion related to axial length and eccentricity among UWF systems.
• These findings provide a reference for correcting size distortion in clinical practice.
• Shape distortion is a unique characteristic observed exclusively in the Daytona UWF imaging system.