4D optical coherence tomography-based micro-angiography achieved by 1.6-MHz FDML swept source

Area of Science:

• Biomedical optics
• Medical imaging
• Microcirculation research

Background:

• Optical coherence tomography (OCT) is a non-invasive imaging modality.
• Visualizing microcirculatory blood flow in vivo is crucial for understanding tissue physiology and pathology.
• Existing OCT techniques may face limitations in speed and resolution for dynamic microvascular imaging.

Purpose of the Study:

• To demonstrate an ultra-high-speed swept-source OCT system for in vivo optical micro-angiography (OMAG).
• To achieve high-volume-rate imaging of microcirculatory tissue beds.
• To validate the system's capability for 4D OMAG of biological tissues.

Main Methods:

• Utilized a 1310-nm Fourier domain mode-locking (FDML) laser with a 1.6-MHz A-line rate.
• Implemented an intensity-based inter-frame subtraction algorithm for blood flow extraction.
• Achieved 4D OMAG at a volume rate of 4.7 volumes/s with a resolution of ~10 µm.

Main Results:

• Demonstrated successful in vivo OMAG of microcirculatory tissue beds.
• Achieved a high frame rate of 3.415 KHz and a volume rate of 4.7 volumes/s.
• Obtained high signal-to-noise ratio (102 dB) and axial resolution (~10 µm) for microvascular imaging.

Conclusions:

• The ultra-high-speed OCT system enables efficient 4D OMAG of in vivo microvasculature.
• The developed system offers a powerful tool for studying microcirculation dynamics.
• This technology advances non-invasive imaging of tissue perfusion.