Title :
Fast magnetization transfer MR imaging
Author :
Vinitski, Simon ; Mohamed, F.B. ; Faro, Scott ; Gonzalez, Carlos ; Ortega, Hector V. ; Mitchell, Donald G. ; Outwater, Eric K.
Author_Institution :
Dept. of Radiol., Thomas Jefferson Univ. Hospital, Philadelphia, PA, USA
Abstract :
We have implemented a new magnetization transfer (MT) technique, to decrease total imaging time and thus improve efficiency of MT based MRI. By judiciously rescaling different RF pulses, and utilizing maximum transmitter gain, we were able to generate very short and powerful MT pulse(s). MRI and MRA in normal and patients with MS were performed, with and without MT application. Phantom experiments indicated 1-2 kHz offset to be the optimal. MT based MRA demonstrated substantial improvement in conspicuity of small vessels with minimum increase in imaging time. MT based MRI showed 30% improvement in MT contrast as well. Importantly, both peak and average SAR values were within FDA approved safety limits
Keywords :
biomedical NMR; dosimetry; magnetisation; FDA approved safety limits; MRA; MRI; MS; MT based MRI; MT contrast; RF pulses; average SAR values; efficiency; fast magnetization transfer MR imaging; imaging time; maximum transmitter gain; multiple sclerosis; normal patients; peak SAR values; phantom experiments; specific absorption rate; total imaging time; Hospitals; Imaging phantoms; Magnetic resonance imaging; Magnetization; Power generation; Protons; Pulse generation; Radio frequency; Radiology; Safety; Transmitters; Water;
Conference_Titel :
Engineering in Medicine and Biology Society, 1994. Engineering Advances: New Opportunities for Biomedical Engineers. Proceedings of the 16th Annual International Conference of the IEEE
Conference_Location :
Baltimore, MD
Print_ISBN :
0-7803-2050-6
DOI :
10.1109/IEMBS.1994.411893