| The very small arteries of the brain, despite being implicated in CAA and Alzheimer's disease, have yet to be imaged in vivo. Improvements to the standard MRA techniques now in use might also allow MRA to close the gap with higher quality but more invasive procedures such as DSA and CTA. Using a combination of very high resolution, contrast agent, application of MT to central k-space, and an optimized acquisition order it is possible to start seeing hints of these vessels. A novel vessel segmentation algorithm that uses localized statistical thresholding and shape filtering is presented as a means of identifying and visualizing these small low contrast vessels.;While we have not yet been able to image many of these tiny vessels we show it is reasonable to assume that with a high channel head coil and one of the new high relaxivity (R1 or R2) contrast agents it will be possible. |
