Real-time phase-resolved optical coherence tomography and optical Doppler tomography.

Area of Science:

• Biomedical Optics
• Medical Imaging
• Ophthalmology

Background:

• Optical Coherence Tomography (OCT) and Optical Doppler Tomography (ODT) are crucial for in vivo imaging.
• Existing methods face limitations in real-time phase resolution and imaging speed.
• Accurate phase information is vital for quantitative blood flow measurements.

Purpose of the Study:

• To develop a novel real-time phase-resolved OCT and ODT system.
• To achieve simultaneous, high-speed imaging of tissue structure and blood flow velocity.
• To overcome limitations of current OCT/ODT systems in phase information retrieval.

Main Methods:

• Developed a system utilizing optical Hilbert transformation for phase resolution.
• Employed circularly polarized reference and linearly polarized sample signals for direct phase acquisition.
• Integrated a resonant scanner (4 kHz) for rapid axial scanning within the interferometer.
• Acquired 200 axial scans at 20 frames per second for real-time imaging.

Main Results:

• Successfully demonstrated a novel real-time phase-resolved OCT and ODT system.
• Achieved high sensitivity and large dynamic range in imaging.
• Acquired simultaneous structural and blood flow velocity images at high frame rates.
• Presented real-time videos of in vivo blood flow in chick chorioallantoic membrane.

Conclusions:

• The developed system offers a significant advancement in real-time OCT and ODT.
• The optical Hilbert transformation method enables direct and accurate phase information retrieval.
• This technology has potential for enhanced diagnosis and monitoring of vascular dynamics in vivo.