@misc{BeckDeuflhardHegeetal., author = {Beck, Rudolf and Deuflhard, Peter and Hege, Hans-Christian and Seebass, Martin and Stalling, Detlev}, title = {Numerical Algorithms and Visualization in Medical Treament Planning}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-2643}, number = {SC-96-54}, abstract = {After a short summary on therapy planning and the underlying technologies we discuss quantitative medicine by giving a short overview on medical image data, summarizing some applications of computer based treatment planning, and outlining requirements on medical planning systems. Then we continue with a description of our medical planning system {\sf HyperPlan}. It supports typical working steps in therapy planning, like data aquisition, segmentation, grid generation, numerical simulation and optimization, accompanying these with powerful visualization and interaction techniques.}, language = {en} } @inproceedings{BeckDeuflhardHegeetal.1997, author = {Beck, Rudolf and Deuflhard, Peter and Hege, Hans-Christian and Seebass, Martin and Stalling, Detlev}, title = {Numerical Algorithms and Visualization in Medical Treament Planning}, series = {Visualization and Mathematics}, booktitle = {Visualization and Mathematics}, editor = {Hege, Hans-Christian and Polthier, Konrad}, publisher = {Springer-Verlag}, pages = {303 -- 328}, year = {1997}, language = {en} } @inproceedings{BeckHegeSeebassetal.1996, author = {Beck, Rudolf and Hege, Hans-Christian and Seebass, Martin and Wust, Peter and Deuflhard, Peter and Felix, Roland}, title = {Adaptive finite element codes for numerical calculations in hyperthermia treatment planning}, series = {Proc. of the 7th Int. Congress on Hyperthermic Oncology, Rome, Italy, April 1996}, volume = {2}, booktitle = {Proc. of the 7th Int. Congress on Hyperthermic Oncology, Rome, Italy, April 1996}, editor = {Franconi, Cafiero}, pages = {515 -- 517}, year = {1996}, language = {en} } @misc{DeuflhardHegeSeebass, author = {Deuflhard, Peter and Hege, Hans-Christian and Seebass, Martin}, title = {Progress Towards a Combined MRI/Hyperthermia System}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-5755}, number = {00-07}, abstract = {Regional hyperthermia, a clinical cancer therapy, is the main topic of the Sonderforschungsbereich Hyperthermia: Scientific Methods and Clinical Applications'' at Berlin. In recent years, technological improvements towards a better concentration of heat to the desired target region have been achieved. These include a rather sophisticated integrated software environment for therapy planning and a new hyperthermia applicator. In a next step, a detailed closed loop monitoring of the actual treatment is to be developed. For this purpose the hyperthermia applicator is combined with an MRI system, which will allow to check the positioning of the patients and to measure individual blood perfusion as well as the 3D temperature distribution. The measurements will then be employed for an on-line control of the whole treatment. In this intended setting, new fast feedback control algorithms will come into play.}, language = {en} } @inproceedings{DeuflhardHegeSeebass2000, author = {Deuflhard, Peter and Hege, Hans-Christian and Seebass, Martin}, title = {Progress Towards a Combined MRI Hyperthermia System}, series = {Proc. Second Int. Congress HIGH CARE 2000, Bochum}, booktitle = {Proc. Second Int. Congress HIGH CARE 2000, Bochum}, editor = {Gr{\"o}nemeyer, W.}, year = {2000}, language = {en} } @misc{DeuflhardLouisSchlegeletal., author = {Deuflhard, Peter and Louis, Alfred and Schlegel, W. and Seebass, Martin}, title = {Workshop "Scientific Computing in der Medizin" SCMED '97}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-5474}, number = {TR-97-05}, abstract = {Die Arbeitstagung \glqq Scientific Computing in der Medizin\grqq , kurz SCMED \grq 97, findet vom 22. - 23. September 1997 im neu errichteten Geb{\"a}ude des Konrad-Zuse-Zentrums auf dem Dahlemer naturwissenschaftlichen Campus der Freien Universt{\"a}t Berlin statt.}, language = {en} } @misc{DeuflhardSeebass, author = {Deuflhard, Peter and Seebass, Martin}, title = {Adaptive Multilevel FEM as Decisive Tools in the Clinical Cancer Therapy Hyperthermia}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-3739}, number = {SC-98-30}, abstract = {The paper surveys recent progress in a joint mathematical-medical project on cancer therapy planning. Within so-called regional hyperthermia the computational task is to tune a set of coupled radiofrequency antennas such that a carefully measured tumor is locally heated, but any outside hot spots are avoided. A mathematical model of the whole clinical system -- air, applicator with antennas, water bolus, individual patient body -- involves Maxwell's equations in inhomogeneous media and a parabolic bioheat transfer equation, which represents a simplified model of heat transfer in the human body (ignoring strong blood vessel heat transport). Both PDEs need to be computed fast and to medical reliability (!) on a workstation within a clinical environment. This requirement triggered a series of new algorithmic developments to be reported here, among which is an adaptive multilevel FEM for Maxwell's equations, which dominates the numerical simulation time. In total, however, the main bulk of computation time (see Table 3 in Section 4 below) still goes into segmentation -- a necessary preprocessing step in the construction a 3D virtual patient from the input of a stack of 2D computed tomograms (left out here).}, language = {en} } @inproceedings{DeuflhardSeebass1999, author = {Deuflhard, Peter and Seebass, Martin}, title = {Adaptive Multilevel FEM as Decisive Tools in the Clinical Cancer Therapy Hyperthermia}, series = {Procs. Eleventh International Conference on Domain Decomposition Methods}, booktitle = {Procs. Eleventh International Conference on Domain Decomposition Methods}, editor = {Lai, Choi-Hong and Bj{\o}rstad, Petter E. and Cross, Mark and Widlund, Olof}, publisher = {DDM-org Press,Bergen}, pages = {403 -- 414}, year = {1999}, language = {en} } @misc{DeuflhardSeebassStallingetal., author = {Deuflhard, Peter and Seebass, Martin and Stalling, Detlev and Beck, Rudolf and Hege, Hans-Christian}, title = {Hyperthermia Treatment Planning in Clinical Cancer Therapy: Modelling, Simulation and Visualization}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-2958}, number = {SC-97-26}, abstract = {\noindent The speaker and his co-workers in Scientific Computing and Visualization have established a close cooperation with medical doctors at the Rudolf--Virchow--Klinikum of the Humboldt University in Berlin on the topic of regional hyperthermia. In order to permit a patient--specific treatment planning, a special software system ({\sf\small HyperPlan}) has been developed. \noindent A mathematical model of the clinical system ({\it radio frequency applicator with 8 antennas, water bolus, individual patient body}) involves Maxwell's equations in inhomogeneous media and a so--called bio--heat transfer PDE describing the temperature distribution in the human body. The electromagnetic field and the thermal phenomena need to be computed at a speed suitable for the clinical environment. An individual geometric patient model is generated as a quite complicated tetrahedral ``coarse'' grid (several thousands of nodes). Both Maxwell's equations and the bio--heat transfer equation are solved on that 3D--grid by means of {\em adaptive} multilevel finite element methods, which automatically refine the grid where necessary in view of the required accuracy. Finally optimal antenna parameters for the applicator are determined . \noindent All steps of the planning process are supported by powerful visualization methods. Medical images, contours, grids, simulated electromagnetic fields and temperature distributions can be displayed in combination. A number of new algorithms and techniques had to be developed and implemented. Special emphasis has been put on advanced 3D interaction methods and user interface issues.}, language = {en} } @inproceedings{DeuflhardSeebassStallingetal.1997, author = {Deuflhard, Peter and Seebass, Martin and Stalling, Detlev and Beck, Rudolf and Hege, Hans-Christian}, title = {Hyperthermia Treatment Planning in Clinical Cancer Therapy:Modelling, Simulation, and Visualization}, series = {Computational Physics, Chemistry and Biology}, volume = {3}, booktitle = {Computational Physics, Chemistry and Biology}, editor = {Sydow, Achim}, publisher = {Wissenschaft und Technik Verlag}, address = {Plenary keynote talk, 15th IMACS World Congress 1997 on Scientific Computation, Modelling and Applied Mathematics}, year = {1997}, language = {en} } @misc{DeuflhardWeiserSeebass, author = {Deuflhard, Peter and Weiser, Martin and Seebass, Martin}, title = {A New Nonlinear Elliptic Multilevel FEM Applied to Regional Hyperthermia}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-3785}, number = {SC-98-35}, abstract = {In the clinical cancer therapy of regional hyperthermia nonlinear perfusion effects inside and outside the tumor seem to play a not negligible role. A stationary model of such effects leads to a nonlinear Helmholtz term within an elliptic boundary value problem. The present paper reports about the application of a recently designed adaptive multilevel FEM to this problem. For several 3D virtual patients, nonlinear versus linear model is studied. Moreover, the numerical efficiency of the new algorithm is compared with a former application of an adaptive FEM to the corresponding instationary model PDE.}, language = {en} } @article{DeuflhardWeiserSeebass2000, author = {Deuflhard, Peter and Weiser, Martin and Seebass, Martin}, title = {A new nonlinear elliptic multilevel FEM in clinical cancer therapy planning}, series = {Comput. Vis. Sci.}, volume = {3}, journal = {Comput. Vis. Sci.}, pages = {115 -- 120}, year = {2000}, language = {en} } @misc{ErdmannLangSeebass, author = {Erdmann, Bodo and Lang, Jens and Seebass, Martin}, title = {Adaptive Solutions of Nonlinear Parabolic Equations with Application to Hyperthermia Treatments}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-3130}, number = {SC-97-44}, abstract = {We present a self-adaptive finite element method to solve nonlinear evolution problems in 3D. An implicit time integrator of Rosenbrock type is coupled with a multilevel approach in space. The proposed method is applied to hyperthermia treatments to demonstrate its potential for the solving of complicated problems.}, language = {en} } @misc{ErdmannLangSeebass, author = {Erdmann, Bodo and Lang, Jens and Seebass, Martin}, title = {Optimization of Temperature Distributions for Regional Hyperthermia Based on a Nonlinear Heat Transfer Model}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-3283}, number = {SC-97-59}, abstract = {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 .}, language = {en} } @inproceedings{ErdmannLangSeebass1997, author = {Erdmann, Bodo and Lang, Jens and Seebass, Martin}, title = {Adaptive Solutions of Nonlinear Parabolic Equations with Application to Hyperthermia Treatments}, series = {CHT'97}, booktitle = {CHT'97}, editor = {de Vahl Davis, G. and Leonardi, E.}, address = {Cesme, Turkey}, pages = {103 -- 110}, year = {1997}, language = {en} } @inproceedings{ErdmannLangSeebass1998, author = {Erdmann, Bodo and Lang, Jens and Seebass, Martin}, title = {Optimization of Temperature Distributions for Regional Hyperthermia based on a Nonlinear Heat Transfer Model}, series = {Biotransport}, volume = {858}, booktitle = {Biotransport}, editor = {Diller, K.}, pages = {36 -- 46}, year = {1998}, language = {en} } @article{ErdmannLangSeebass1999, author = {Erdmann, Bodo and Lang, Jens and Seebass, Martin}, title = {The Impact of a Nonlinear Heat Transfer Model for Temperature Control in Regional Hyperthermia}, series = {IEEE Transactions on Biomedical Engineering}, volume = {49}, journal = {IEEE Transactions on Biomedical Engineering}, number = {9}, pages = {1129 -- 1138}, year = {1999}, language = {en} } @article{GellermannWustStallingetal.2000, author = {Gellermann, Johanna and Wust, Peter and Stalling, Detlev and Seebass, Martin and Nadobny, Johanna and Beck, Rudolf and Hege, Hans-Christian and Deuflhard, Peter and Felix, Roland}, title = {Clinical evaluation and verification of the hyperthermia treatment planning system hyperplan}, series = {Int J Radiat Oncol Biol Phys}, volume = {47}, journal = {Int J Radiat Oncol Biol Phys}, number = {4}, pages = {1145 -- 1156}, year = {2000}, language = {en} } @inproceedings{GellermannWustStallingetal.1997, author = {Gellermann, Johanna and Wust, Peter and Stalling, Detlev and Tilly, Wolfgang and Nadobny, Johanna and Seebass, Martin and Deuflhard, Peter and Felix, Roland and Budach, Volker}, title = {First Clinical Experiences with the Hyperthermia Planning System HyperPlan}, series = {Proc. 16th Ann. Meeting Europ. Soc. Hyperthermic Oncology (ESHO-97), Berlin, Germany, April 1997}, booktitle = {Proc. 16th Ann. Meeting Europ. Soc. Hyperthermic Oncology (ESHO-97), Berlin, Germany, April 1997}, pages = {79}, year = {1997}, language = {en} } @misc{HegeSeebassStallingetal., author = {Hege, Hans-Christian and Seebass, Martin and Stalling, Detlev and Z{\"o}ckler, Malte}, title = {A Generalized Marching Cubes Algorithm Based on Non-Binary Classifications}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-2741}, number = {SC-97-05}, abstract = {We present a new technique for generating surface meshes from a uniform set of discrete samples. Our method extends the well-known marching cubes algorithm used for computing polygonal isosurfaces. While in marching cubes each vertex of a cubic grid cell is binary classified as lying above or below an isosurface, in our approach an arbitrary number of vertex classes can be specified. Consequently the resulting surfaces consist of patches separating volumes of two different classes each. Similar to the marching cubes algorithm all grid cells are traversed and classified according to the number of different vertex classes involved and their arrangement. The solution for each configuration is computed based on a model that assigns probabilities to the vertices and interpolates them. We introduce an automatic method to find a triangulation which approximates the boundary surfaces - implicitly given by our model - in a topological correct way. Look-up tables guarantee a high performance of the algorithm. In medical applications our method can be used to extract surfaces from a 3D segmentation of tomographic images into multiple tissue types. The resulting surfaces are well suited for subsequent volumetric mesh generation, which is needed for simulation as well as visualization tasks. The proposed algorithm provides a robust and unique solution, avoiding ambiguities occuring in other methods. The method is of great significance in modeling and animation too, where it can be used for polygonalization of non-manifold implicit surfaces.}, language = {en} }