Numerical method for axial motion artifact correction in retinal spectral-domain optical coherence tomography

Area of Science:

• Biomedical Optics
• Medical Imaging Technology
• Optical Physics

Background:

• Spectral-domain optical coherence tomography (SD OCT) is susceptible to image distortions.
• Fluctuations in the distance between the sample and the OCT system cause artifacts.
• These distortions degrade the quality and accuracy of OCT images, particularly in dynamic or in vivo applications.

Purpose of the Study:

• To propose and experimentally validate a numerical method for compensating image distortions in SD OCT.
• To address image artifacts arising from random distance fluctuations to the object.
• To enhance the robustness and reliability of SD OCT imaging.

Main Methods:

• A numerical method analyzing phase shifts between adjacent scans was developed.
• Micrometer-scale displacements were identified through phase shift analysis.
• Compensation was achieved via phase-frequency correction in the spectral space.

Main Results:

• The proposed method effectively compensated for image distortions caused by distance fluctuations.
• Experimental validation included model experiments with controlled object movements (harmonic and random).
• Successful in vivo application was demonstrated during human retinal imaging.

Conclusions:

• The developed numerical method offers an efficient solution for correcting SD OCT image distortions.
• Phase-frequency correction in spectral space is a viable strategy for handling micrometer-scale displacements.
• This technique has significant potential for improving in vivo SD OCT imaging, especially for dynamic samples.