Handheld common-path swept-source optical coherence tomography angiography.

Area of Science:

• Biomedical Optics
• Medical Imaging Technology

Background:

• Optical Coherence Tomography Angiography (OCTA) is crucial for visualizing microvasculature.
• Existing OCTA systems can be bulky and sensitive to environmental changes, limiting handheld applications.
• Developing compact, stable OCTA probes is essential for point-of-care diagnostics.

Purpose of the Study:

• To develop a handheld Optical Coherence Tomography Angiography (OCTA) system.
• To achieve stable and fast imaging for clinical skin screening.
• To demonstrate the system's capability in imaging in vivo human skin microvasculature.

Main Methods:

• Utilized a high-speed (200 kHz) swept laser.
• Employed a dual-reference common-path configuration for enhanced stability.
• Integrated a single circulator as the primary optical element for a compact design.

Main Results:

• Achieved a minimum detectable flow velocity of approximately 0.08 mm/s.
• Demonstrated sub-micrometer envelope stability and nanometer-level phase variation.
• Successfully imaged in vivo skin structures and microvasculature in human subjects.

Conclusions:

• The developed handheld OCTA system provides stable, high-sensitivity imaging.
• The common-path design ensures cost-effectiveness and compactness for handheld use.
• This technology holds significant potential for clinical skin screening and diagnostics.