Suppressing Unencoded MRI Signal Contribution in Multi-Phase Myocardial Tagging and Phase-Contrast Based Methods
Description of Invention:
The invention is a method for obtaining clear functional magnetic resonance (MR) cardiac images without significantly increasing signal acquisition time. During functional magnetic resonance imaging (MRI) the specimen magnetization is spatially encoded by application of one or more radio frequency pulses (RF) and gradient magnetic fields. This spatially encoded magnetization is then read out to produce images that can be used to assess specimen motion. During this process the contrast decreases from the beginning of the cardiac cycle as the magnetization decays or relaxes, making the images more difficult to process and interpret over time. This is currently solved by acquiring the images twice (with a modified signal excitation phase) to suppress unwanted unencoded MRI signal contributions; therefore improving the contrast. Unfortunately, this prolongs the acquisition by a factor of two. In the invention, an RF inversion pulse is used to suppress the undesirable unencoded MRI signal contributions, thereby improving the contrast. This RF frequency drives the undesired signal to an equilibrium around zero, while preserving the desired encoded signal. The application of the RF inversion pulse doubles the resolution of the image and does not increase acquisition time. It allows for immediate evaluation of myocardial contractility throughout the whole cardiac cycle without requiring user intervention during phase-based data processing. There is also the possibility that this method could be used in other areas of the body, including the spinal cord, and the invention may be applicable to the study of brain motion. This new method speeds up the quantification of datasets, suppresses undesired signal contributions, and doubles the resolution of the images without doubling acquisition time.
For Additional Information Please Contact: Michael Shmilovich J.D.
NIH Office of Technology Transfer
6011 Executive Blvd, Suite 325
Rockville, MD 20852-3804
Phone: (301) 435-5019
Email: shmilovm@mail.nih.gov
Fax: (301) 402-0220
