Full-range Fourier domain Doppler optical coherence tomography based on sinusoidal phase modulation.

Area of Science:

• Biomedical Optics
• Medical Imaging Technology
• Optical Physics

Background:

• Fourier domain optical coherence tomography (FD-OCT) is a powerful imaging technique.
• Doppler OCT (DOCT) enables non-invasive blood flow measurement.
• Existing FD-DOCT methods face challenges with velocity ambiguity and sensitivity.

Purpose of the Study:

• To propose and validate a novel full-range FD-DOCT system using sinusoidal phase modulation for B-M scans.
• To enhance velocity sensitivity and eliminate mirror image artifacts in FD-DOCT.
• To demonstrate the capability of the proposed system for accurate flow velocity detection.

Main Methods:

• Implementation of a full-range FD-DOCT system with sinusoidal B-M scanning.
• Utilizing phase modulation to maintain zero optical path difference (OPD) position.
• Analyzing velocity sensitivity based on OPD and scanning point intervals.
• Performing Doppler imaging on a flow phantom and an in vivo biological sample.

Main Results:

• The sinusoidal B-M scan in FD-DOCT maintains a stable zero OPD position.
• Achieved high phase sensitivity around the zero OPD position, enabling high velocity sensitivity.
• Successfully eliminated mirror image artifacts common in conventional FD-DOCT.
• Verified flow velocity detection capabilities through phantom and in vivo imaging.

Conclusions:

• The proposed full-range FD-DOCT with sinusoidal phase modulation offers superior velocity sensitivity.
• This novel approach overcomes limitations of traditional FD-DOCT, particularly mirror image artifacts.
• The system demonstrates significant potential for accurate and sensitive blood flow imaging in biological applications.