Project: Research project

Project Details


DESCRIPTION (Adapted from Applicant's Abstract): The applicants propose to
further develop techniques for real-time interactive imaging of the coronary
arteries. Based on results of the previous funding cycle and the current status
of the field, the applicants propose that the principal technical challenges
facing coronary artery MRA today are improved spatial resolution, improved
technical reliability, and the need for sub-10 sec acquisition times. To
address these issues, the applicants propose to use contrast material for
improved depiction of the intraluminal signal. Further, would develop a novel
dual-flip - angle acquisition method which, when combined with complex
subtraction, is expected to allow the small acquisition time of 2D imaging and
the high sensitivity to contrast along the slab direction of 3D imaging. The
specific hypothesis of this proposal is that dual flip angle imaging can be
used to provide high contrast sub-mm spatial resolution in imaging of the
coronary arteries. Three projects will be studied: 1. Dual Flip Angle Imaging
Physics. The applicants propose to develop a technique in which the vascular
signal can be isolated by using complex subtraction of data acquired at
different flip angles. They hypothesize that this method will allow the
accurate depiction of a contrast-enhanced blood vessel whose diameter in the
slice-select (Z) direction is smaller than the slice thickness. This will be
studied by determination of optimum flip angles and consideration of various
means for complex subtraction; 2. Real-Time Implementation. They will develop
gradient echo and multi-shot EPI sequences which toggle between low and high
flip angles on consecutive repetitions. Complex subtraction will be performed
online, and acquisition and reconstruction adapted to allow for arbitrary
cardiac phases; and 3. In Vivo Evaluation. The techniques will be studied in
vivo. They hypothesize that coronary artery images formed from data obtained
using a predefined cardiac phase known to have motion within some acceptable
tolerance are less blurred than images obtained using a temporally fixed
cardiac phase. To determine the cardiac phase suitable for high resolution
imaging, lateral coronary artery motion will be measured on a vessel-specific
basis at 40 Hz realtime. The methods will be studied in a pig model of coronary
artery stenosis and compared with x-ray angiography.
StatusNot started


Explore the research topics touched on by this project. These labels are generated based on the underlying awards/grants. Together they form a unique fingerprint.