Motion correction for phase-resolved dynamic optical coherence tomography imaging of rodent cerebral cortex

Abstract

Cardiac and respiratory motions in animals are the primary source of image quality degradation in dynamic imaging studies, especially when using phase-resolved imaging modalities such as spectral-domain optical coherence tomography (SD-OCT), whose phase signal is very sensitive to movements of the sample. This study demonstrates a method with which to compensate for motion artifacts in dynamic SD-OCT imaging of the rodent cerebral cortex. We observed that respiratory and cardiac motions mainly caused, respectively, bulk image shifts (BISs) and global phase fluctuations (GPFs). A cross-correlation maximization-based shift correction algorithm was effective in suppressing BISs, while GPFs were significantly reduced by removing axial and lateral global phase variations. In addition, a non-origin-centered GPF correction algorithm was examined. Several combinations of these algorithms were tested to find an optimized approach that improved image stability from 0.5 to 0.8 in terms of the cross-correlation over 4 s of dynamic imaging, and reduced phase noise by two orders of magnitude in ~8% voxels.

Quantitative Imaging of Cerebral Blood Flow Velocity and Intracellular Motility using Dynamic Light Scattering–Optical Coherence Tomography

“…16 We used a large-bandwidth near infrared light source (1310±170 nm) for a large imaging depth (1 mm) and high axial resolution (3.5 mm in tissue). The light source with the center wavelength of 1300 nm was used as it offers a larger imaging depth than conventional 800-nm light sources.…”

“…An angiogram was obtained using the method described previously. [16][17][18] Dynamic Light Scattering-Optical Coherence Tomography Analysis Technical details of DLS-OCT theory and analysis have been described in our previous publication. 19 In brief, dynamic OCT imaging of a sample produced four-dimensional (space and time) data of the complex-valued reflectivity, R(r, t).…”

Three-dimensional motion correction using speckle and phase for in vivo computed optical interferometric tomography

“…As the oversampling decreases (dy/ω 0 increases), the RMS error increases. Here, as previously used in [19], ω 0 is the 1/e radius of the diffraction-limited spot size at the Gaussian beam focus. The RMS error was compared to a Monte Carlo simulation.…”

“…Previous work typically required either stable data at the time of imaging [17,18], or a phase reference was used, such as a coverslip placed on the sample or tissue, to compensate for optical path length fluctuations [14]. Additionally, other efforts have shown that motion could be corrected by using only the acquired OCT data for numerical defocus correction and other phase-resolved techniques [19,20]. Most of these techniques, though, are restricted to one-or two-dimensional motion correction.…”

Regression-based algorithm for bulk motion subtraction in optical coherence tomography angiography

“…Methods that iteratively maximize cross-correlation of successive B-scans prior to OCTA processing have been used to estimate displacement and compensate bulk image shifts as well as global phase variations in the axial and lateral directions [34][35][36]. However, the actual three-dimensional nature of eye motion during scanning challenges this approach, which is limited to in-plane shifts.…”