TY - GEN A1 - Lang, Jens A1 - Erdmann, Bodo A1 - Seebass, Martin T1 - Impact of Nonlinear Heat Transfer on Temperature Control in Regional Hyperthermia N2 - We describe an optimization process specially designed for regional hyperthermia of deep seated tumors in order to achieve desired steady--state temperature distributions. A nonlinear three--dimensional heat transfer model based on temperature--dependent blood perfusion is applied to predict the temperature. Using linearly implicit methods in time and adaptive multilevel finite elements in space, we are able to integrate efficiently the instationary nonlinear heat equation with high accuracy. Optimal heating is obtained by minimizing an integral object function which measures the distance between desired and model predicted temperatures. A sequence of minima is calculated from successively improved constant--rate perfusion models employing a damped Newton method in an inner iteration. We compare temperature distributions for two individual patients calculated on coarse and fine spatial grids and present numerical results of optimizations for a Sigma 60 Applicator of the BSD 2000 Hyperthermia System. T3 - ZIB-Report - SC-97-73 Y1 - 1998 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-3426 ER - TY - GEN A1 - Erdmann, Bodo A1 - Lang, Jens A1 - Seebass, Martin T1 - Optimization of Temperature Distributions for Regional Hyperthermia Based on a Nonlinear Heat Transfer Model N2 - We describe an optimization process specially designed for regional hyperthermia of deap seated tumors in order to achieve desired steady--state temperature distributions. A nonlinear three--dimensional heat--transfer model based on temperature--dependent blood perfusion is applied to predict the temperature. Optimal heating is obtained by minimizing an integral object function which measures the distance between desired and model predicted temperatures. Sequential minima are calculated from successively improved constant--rate perfusion models employing a damped Newton method in an inner iteration. Numerical results for a Sigma 60 applicator are presented. This work has been supported by Deutsche Forschungsgemeinschaft (DFG) within the Sonderforschungsbereich 273 \glqq Hyperthermie: Methodik und Klinik \grqq . T3 - ZIB-Report - SC-97-59 Y1 - 1997 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-3283 ER - TY - CHAP A1 - Beck, Rudolf A1 - Deuflhard, Peter A1 - Hege, Hans-Christian A1 - Seebass, Martin A1 - Stalling, Detlev ED - Hege, Hans-Christian ED - Polthier, Konrad T1 - Numerical Algorithms and Visualization in Medical Treament Planning T2 - Visualization and Mathematics Y1 - 1997 SP - 303 EP - 328 PB - Springer-Verlag ER - TY - CHAP A1 - Beck, Rudolf A1 - Hege, Hans-Christian A1 - Seebass, Martin A1 - Wust, Peter A1 - Deuflhard, Peter A1 - Felix, Roland ED - Franconi, Cafiero T1 - Adaptive finite element codes for numerical calculations in hyperthermia treatment planning T2 - Proc. of the 7th Int. Congress on Hyperthermic Oncology, Rome, Italy, April 1996 Y1 - 1996 VL - 2 SP - 515 EP - 517 ER - TY - CHAP A1 - Nadobny, Johanna A1 - Sullivan, Dennis A1 - Wust, Peter A1 - Seebass, Martin A1 - Deuflhard, Peter A1 - Felix, Roland T1 - A High Resolution Interpretation at Arbitrary Interfaces for the FDTD Method T2 - IEEE Transactions on Microwave Theory and Techniques Y1 - 1998 VL - 46 IS - 11 SP - 1759 EP - 1766 ER - TY - CHAP A1 - Nadobny, Johanna A1 - Wust, Peter A1 - Seebass, Martin A1 - Deuflhard, Peter A1 - Felix, Roland ED - Simunic, D. T1 - The Use of the Volume-Surface Integral Equation Method (VSIE) for Antenna Problems T2 - Proc. COST 244 meeting on Reference Models for Bioelectromagnetic Test of Mobile Communication Systems, Roma, November 1994 Y1 - 1995 SP - 67 EP - 74 ER - TY - JOUR A1 - Nadobny, Johanna A1 - Wust, Peter A1 - Seebass, Martin A1 - Deuflhard, Peter A1 - Felix, Roland T1 - A Volume-Surface Integral Method for Solving Maxwell’s Equations in Electrically Inhomogeneous Media Using Tetrahedral Grids JF - IEEE Transactions on Microwave Theory and Techniques Y1 - 1996 VL - 44 IS - 4 SP - 543 EP - 554 ER - TY - CHAP A1 - Nadobny, Johanna A1 - Wust, Peter A1 - Seebass, Martin A1 - Stalling, Detlev A1 - Hege, Hans-Christian A1 - Deuflhard, Peter A1 - Felix, Roland T1 - A Quantitative Comparison between the VSIE and the FDTD method using Electrically Equivalent Patient and Antenna Models T2 - Proc. 16th Ann. Meeting Europ. Soc. Hyperthermic Oncology (ESHO-97), Berlin, Germany, April 1997 Y1 - 1997 SP - 145 ER - TY - CHAP A1 - Nadobny, Johanna A1 - Wust, Peter A1 - Wlodarczyk, Waldemar A1 - Seebass, Martin A1 - Deuflhard, Peter A1 - Felix, Roland ED - Franconi, Cafiero T1 - Simulation Studies for Combination of Hyperthermia and Magnetic Resonance Systems T2 - Proc. of the 7th Int. Congress on Hyperthermic Oncology, Rome, Italy, April 1996 Y1 - 1996 VL - 2 SP - 549 EP - 551 ER - TY - CHAP A1 - Deuflhard, Peter A1 - Hege, Hans-Christian A1 - Seebass, Martin ED - Grönemeyer, W. T1 - Progress Towards a Combined MRI Hyperthermia System T2 - Proc. Second Int. Congress HIGH CARE 2000, Bochum Y1 - 2000 ER -