Extended axial imaging range, widefield swept source optical coherence tomography angiography

Area of Science:

• Ophthalmic imaging
• Optical coherence tomography
• Angiography

Background:

• Widefield imaging is crucial for comprehensive retinal vasculature assessment.
• Previous optical coherence tomography angiography (OCTA) systems faced limitations in speed and field of view.

Purpose of the Study:

• To develop a high-speed swept source OCT system for widefield OCT angiography (OCTA).
• To achieve high-resolution OCTA imaging with extended field of view and rapid acquisition times.

Main Methods:

• Utilized a swept source OCT system with an extended axial imaging range.
• Employed an electrical lens for fast, automatic focusing.
• Implemented split-spectrum amplitude and phase-gradient angiography with two B-scan repetitions.
• Applied an improved post-processing algorithm to reduce artifacts and noise.

Main Results:

• Demonstrated high contrast 3x3 mm OCTA images (400x400 pixels) in 3 seconds.
• Acquired high-definition 8x6 mm and 12x6 mm OCTA images (850x400 pixels) in 4 seconds.
• Generated widefield (8x11 mm) and ultra-widefield (up to 22x22 mm) OCTA images through scan montaging.

Conclusions:

• The developed high-speed swept source OCT system enables efficient widefield and ultra-widefield OCTA imaging.
• The system provides high-resolution, artifact-reduced visualization of retinal vasculature.
• This technology has the potential to significantly advance ophthalmic diagnostics and research.