Abstract
We propose a simple and optimized method for acquiring a wide velocity range of blood flow using Doppler optical microangiography. After characterizing the behavior of the scanner in the fast scan axis, a step-scanning protocol is developed by utilizing repeated A-scans at each step. Multiple velocity range images are obtained by the high-pass filtering and Doppler processing of complex signals between A-scans within each step with different time intervals. A phase variance mask is then employed to segment meaningful Doppler flow signals from noisy phase background. The technique is demonstrated by imaging in vivo mouse brain with skull left intact to provide bidirectional images of cerebral blood flow with high quality and wide velocity range.
Highlights
Doppler optical microangiography (DOMAG)[1] is a technological extension to Doppler optical coherence tomography (DOCT),[2] in which DOCT is combined with recently developed OMAG technique[3] to provide velocity mapping of blood flows within tissue beds in vivo
The shorter T, i.e., faster imaging speed, is usually required to map the velocities of faster flow, but at an expense of slower ones and vice versa. It is currently difficult for DOMAG/DOCT to provide the read-out of blood flows within tissue beds that have wide velocity distributions
We demonstrate the utility of the mDOMAG in the imaging of 3-D cerebral blood flow (CBF) within a mouse brain in vivo
Summary
Doppler optical microangiography (DOMAG)[1] is a technological extension to Doppler optical coherence tomography (DOCT),[2] in which DOCT is combined with recently developed OMAG technique[3] to provide velocity mapping of blood flows within tissue beds in vivo. The maximal and minimal velocities that are detectable in one B-scan [or three-dimensional (3-D) scan] are determined by the time interval T, the πambiguity and the system phase noise level.[2] The shorter T, i.e., faster imaging speed, is usually required to map the velocities of faster flow, but at an expense of slower ones and vice versa. It is currently difficult for DOMAG/DOCT to provide the read-out of blood flows within tissue beds that have wide velocity distributions. We propose an optimized method in which S-scan is employed in the fast axis while a number of repeated A-scans at each step are acquired only after the scanner has been stabilized
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
