Artifact removal in Fourier-domain OCT with a rotating probe

摘要

This paper reports the study of a Swept Source Optical Coherence Tomography (SS-OCT) setup to remove depth degeneracy for measurements performed with a rotating probe. One of the main drawbacks of SS-OCT is its inability to differentiate positive and negative depths. Some setups have already been proposed to remove this depth ambiguity by introducing a modulation by means of electro-optic or acousto-optic modulators. For cross-sectional imaging, we developed a setup that uses a piezoelectric fiber stretcher to generate a periodic phase shift between successive A-scans, thus introducing a transverse modulation. The depth ambiguity is then resolved by performing a Fourier processing in the transverse direction before processing the data in the axial direction. This approach can also be applied to a rotating probe with a cylindrical geometry by introducing phase shifts between A-scans belonging to successive rotations or between successive B-scans. In the later case, the depth degeneracy is removed by first performing a Fourier processing along the cylindrical axis. We validate this approach by processing images acquired with our catheterized probe based on a rotating fiber and fitted with a GRIN lens and a prism at the tip.