Title :
Advances in the Planning and Control of the MR-guided Regional Hyperthermia Applications
Author :
Nadobny, J. ; Weihrauch, M. ; Weiser, M. ; Gellermann, J. ; Wlodarczyk, W. ; Budach, V. ; Wust, P.
Author_Institution :
Clinic for Radiat. Oncology, Berlin
Abstract :
A novel method for improved planning and control of the magnetic resonance (MR)-guided hyperthermia (HT) has been developed and tested in the combined Berlin MR-HT hybrid system, consisting of the 12-channel HT applicator Sigma-Eye and of the MR tomograph Siemens MAGNETOM Symphony 1.5 T. The method is based on a step-by-step adaptation of antenna profiles (single antenna fields) using MR temperature rise measurements obtained by the proton resonance frequency shift (PRFS) method. A Gauss-Newton algorithm is applied as an iterative solver for adaptation. It is shown that, using the finite-difference time-domain (FDTD) method as initial estimate for antenna profiles, already after few adaptation steps a significant improvement of the specific absorption rate (SAR) predictability in the MR-HT hybrid system is reached.
Keywords :
antennas; biomedical MRI; hyperthermia; iterative methods; radiation therapy; Berlin MR-HT hybrid system; FDTD method; Gauss-Newton algorithm; HT applicator Sigma-Eye; MR tomograph Siemens MAGNETOM symphony; MR-guided regional hyperthermia applications; finite-difference time-domain method; iterative solver; magnetic resonance; proton resonance frequency shift method; specific absorption rate; Adaptive arrays; Applicators; Control systems; Finite difference methods; Hyperthermia; Magnetic resonance; System testing; Temperature control; Temperature measurement; Time domain analysis;
Conference_Titel :
Electromagnetics in Advanced Applications, 2007. ICEAA 2007. International Conference on
Conference_Location :
Torino
Print_ISBN :
978-1-4244-0767-5
Electronic_ISBN :
978-1-4244-0767-5
DOI :
10.1109/ICEAA.2007.4387478
