Calibrated uncoupling of tightly coupled concentric surface coils for in vivo NMR |
| |
Authors: | M R Bendall |
| |
Institution: | School of Science, Griffith University, Nathan, Queensland, Australia. |
| |
Abstract: | Three known active methods of detuning rf coils have been tested by determining the efficiency of uncoupling two concentric transmit surface coils in a double-coil probe. In a comparison at 80 MHz, the method based on the use of lambda/4 cables was found to have advantages. These methods utilize the introduction of an additional resonance at the frequency of interest to completely detune a coil. By offsetting the detuning of the coil (by offsetting the additional resonance) a calibrated fraction of the rf field of the detuned coil can be added to or substracted from the rf field of the neighboring coil. |
| |
Keywords: | |
|
|