![]() This method allows the use of phase information to map the microvasculature in tissue without the correction of bulk motion and laser trigger jitter induced phase artifacts. Our results show that speckle introduces a limit to the accuracy of phase-sensitive OCT and that speckle brightness should be considered to avoid erroneous interpretation of experimental data. A phase gradient angiography (PGA) method is proposed for optical coherence tomography (OCT). Clinical investigations that used OCTA have increased exponentially in the. With the advent of high-speed OCT and efficient algorithms, practical OCTA of ocular circulation is now available to ophthalmologists. Finally, we apply these new results in compression OCE to demonstrate a ten-fold improvement in strain sensitivity, and a five-fold improvement in contrast-to-noise by incorporating independent speckle realizations. Optical coherence tomography angiography (OCTA) is a noninvasive approach that can visualize blood vessels down to the capillary level. Experimental measurements show an almost three-fold degradation in sensitivity between regions of high and low speckle brightness at a constant OCT SNR. Robust methods to compute tissue displacements in optical coherence elastography (OCE) data are paramount, as they play a significant role in the accuracy of tissue elastic properties estimation. ![]() We describe how the inaccuracy in speckle reduces phase difference sensitivity and introduce a new metric, speckle brightness, to quantify the amount of constructive interference at a given location in an OCT image. In this study, for the first time, we demonstrate, through theory and experiment that speckle significantly lowers the accuracy of phase-sensitive OCT in a manner not accounted for by the OCT signal-to-noise ratio (SNR). However, this approach is not representative of turbid samples, such as tissue, which exhibit speckle. In phase-sensitive OCT, motion is typically estimated using a model of the OCT signal derived from a single reflector. Our method can potentially be useful for applications where high-speed recording of multiple en-face images is crucial.Phase-sensitive optical coherence tomography (OCT) is used to measure motion in a range of techniques, such as Doppler OCT and optical coherence elastography (OCE). By exploiting the interaction between the polarization state of light and tissue, additional structural and functional (physiological) information can be extracted. We demonstrated the single-shot recording of 7 different depth images at 10 µm for biological tissues. Polarization-sensitive optical coherence tomography (PS-OCT) maps depth- and spatially-resolved changes in the polarization state of light induced by anisotropic tissue properties. By recording a single interference image between the reflected wave from a sample and these multiple reference beams, we reconstruct full-field images at multiple depths associated with the pathlengths of the individual reference beams. We combine a 2D diffraction grating and a custom-made echelon to prepare multiple reference beams having different pathlengths and propagating angles. Here, we present a full-field OCT system that can obtain multi-depth information at once by a single-shot recording. On the contrary, full-field OCT needs the scanning of imaging depth while it records a full lateral information at once. ![]() Point-scanning based approaches, such as swept-source OCT and spectral domain OCT, can obtain a depth information at once, but they require lateral scan for full 3D imaging. Optical coherence tomography (OCT), first proposed by David in 1991, is a novel three-dimensional (3D) imaging technology with noninvasive, high-resolution, and low-cost characteristics, which can perform high-definition cross-sectional imaging of the biological tissue in situ by measuring the reflected light signal, especially for transparent or translucent samples. Fast 3D volumetric imaging has been essential for biology, medicine and industrial inspections, and various optical coherence tomography (OCT) methods have been developed to meet such needs.
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