Date of Award
Summer 1994
Document Type
Thesis - Restricted
Degree Name
Master of Science (MS)
Department
Biomedical Engineering
First Advisor
Ishii, Thomas K.
Abstract
The birdcage resonator has been used for over ten years to produce a rotating magnetic flux density for the excitation process necessary for Magnetic Resonance Imaging (MRI). Patients will load the birdcage differently which necessitates the calibration of transmit power on a per patient basis. The method to perform this power calibration currently implemented on GE SIGNA MRI systems is NMR (Nuclear Magnetic Resonance) based. The method, called auto-prescan (APS), has major drawbacks including the amount of time the method requires on a per patient basis. A real-time electronic method for power calibration, termed B1 feedback, is presented. A theoretical justification for using the b1 feedback method is developed. Experimental results are presented that show a discrepancy in NMR flip angle produced by the APS and B1 feedback methods of 1.53 degrees for a desired NMR flip angle of 90 degrees.
Recommended Citation
Katcha, Jason S., "A Magnetic Flux Density Control System for the Birdcage Resonator" (1994). Master's Theses (1922-2009) Access restricted to Marquette Campus. 4898.
https://epublications.marquette.edu/theses/4898