title: Multiscale optimization of the probe placement for radiofrequency ablation.
abstract: OBJECTIVE
  We present a model for the optimal placement of mono- and bipolar probes in radiofrequency (RF) ablation. The model is based on a system of partial differential equations that describe the electric potential of the probe and the steady state of the induced heat distribution.
  
  
  METHODS
  To optimize the probe placement we minimize a temperature-based objective function under the constraining system of partial differential equations. Further, the extension of the resulting optimality system for the use of multiple coupled RF probes is discussed. We choose a multiscale gradient descent approach to solve the optimality system.
  
  
  RESULTS
  This article describes the discretization and implementation of the approach with finite elements on three-dimensional hexahedral grids.
  
  
  CONCLUSIONS
  Applications of the optimization to artificial test scenarios as well as a comparison to a real RF ablation show the usefulness of the approach.
authors.affiliation: Center of Complex Systems and Visualization, University of Bremen, Germany. inga@cevis.uni-bremen.de
authors.forename: Inga
authors.initials: I
authors.lastname: Altrogge
authors.forename: Tobias
authors.initials: T
authors.lastname: Preusser
authors.forename: Tim
authors.initials: T
authors.lastname: Kröger
authors.forename: Christof
authors.initials: C
authors.lastname: Büskens
authors.forename: Philippe L
authors.initials: PL
authors.lastname: Pereira
authors.forename: Diethard
authors.initials: D
authors.lastname: Schmidt
authors.forename: Heinz-Otto
authors.initials: HO
authors.lastname: Peitgen
mesh_terms: D001831:Body Temperature; D017115:Catheter Ablation / Q000295:instrumentation / Q000379:methods*; D003198:Computer Simulation; D006498:Hepatectomy / Q000379:methods*; D006801:Humans; D008099:Liver / Q000503:physiopathology* / Q000601:surgery*; D008954:Models, Biological; D025321:Surgery, Computer-Assisted / Q000379:methods*; D013817:Thermography / Q000379:methods