Motion-insensitive optical coherence tomography based micro-angiography

Abstract

An improved image processing procedure for suppressing the phase noise due to a motion artifact acquired during optical coherence tomography scanning and effectively illustrating the blood vessel distribution in a living tissue is demonstrated. This new processing procedure and the widely used procedure for micro-angiography application are based on the selection of high-frequency components in the spatial-frequency spectrum of B-mode scanning (x-space), which are contributed from the image portions of moving objects. However, by switching the processing order between the x-space and k-space, the new processing procedure shows the superior function of effectively suppressing the phase noise due to a motion artifact. After the blood vessel positions are precisely acquired based on the new processing procedure, the projected blood flow speed can be more accurately calibrated based on a previously reported method. The demonstrated new procedure is useful for clinical micro-angiography application, in which a stepping motor of generating motion artifacts is usually used in the scanning probe.

Photothermal Behaviors of Flowing Media Caused by Localized Surface Plasmon Resonance of Au Nanorings

“…The used OCT system is built based on a swept source OCT configuration, as schematically shown in Fig. 2a [21]. Here, the swept source has a sweeping wavelength range of 170 nm (Santec, HSL2100).…”

Review of speckle and phase variance optical coherence tomography to visualize microvascular networks

“…23 The power Doppler OCT and/or optical angiography/microangiography (OMAG) are other imaging techniques based on the Doppler effect that is able to isolate blood flow signals from the static tissue background. [24][25][26][27][28][29][30][31][32][33][34][35][36] This method does not allow visualization of flow velocity directly; it provides a measure of the total backscattered optical signal attributable to moving targets with higher SNR 37 compared to DOCT. Unlike phase-based approaches, OMAG directly analyzes and processes an image, which can minimize the phase instability noise.…”

Two-Level Optical Coherence Tomography Scheme for Suppressing Spectral Saturation Artifacts

“…If you take a photo of a flying ball, the blur on the picture is a demonstration of this type of motion artifacts. Since this kind of artifacts is prevailing in biomedical applications, several approaches to solving the motion artifacts have already been published [5–7]. …”