Spectral phase based k-domain interpolation for uniform sampling in swept-source optical coherence tomography.

Area of Science:

• Biomedical optics
• Medical imaging technology

Background:

• Swept-source optical coherence tomography (SS-OCT) is a powerful imaging modality.
• Accurate k-domain interpolation is crucial for high-resolution SS-OCT imaging.
• Existing methods for spectral phase calibration and interpolation have limitations.

Purpose of the Study:

• To develop an efficient direct k-domain interpolation method for SS-OCT based on spectral phase.
• To improve the imaging quality, resolution, and signal-to-noise ratio (SNR) of SS-OCT.
• To compare the proposed method with existing spectral phase and intensity-based calibration techniques.

Main Methods:

• Simultaneous detection and digitization of Mach-Zehnder interferometer (MZI) calibration signals and Michelson interferometer OCT imaging signals.
• Direct k-domain interpolation of OCT signals using spectral phase derived from MZI calibration.
• Fourier transform of interpolated k-domain data to obtain depth profiles.
• In vivo imaging of human finger skin and nail fold.

Main Results:

• The proposed spectral phase-based direct k-domain interpolation method significantly improves imaging quality.
• Enhanced resolution and signal-to-noise ratio were achieved compared to time-domain interpolation and intensity-based calibration.
• Successful in vivo imaging of human skin and nail fold demonstrates the method's efficacy.

Conclusions:

• The proposed direct k-domain interpolation method offers an efficient and effective approach for SS-OCT.
• This technique provides superior imaging performance, making it valuable for biomedical applications.
• The method overcomes limitations of previous calibration and interpolation strategies in SS-OCT.