title: Parametric study of irreversible electroporation with different needle electrodes: electrical and thermal analysis.
abstract: OBJECTIVE
  Irreversible electroporation (IRE) is a new tumour ablation method used in cancer treatment procedures. In a successful IRE treatment it is crucial to impose minimum thermal damage to the tumour and its surrounding healthy tissue, while subjecting the entire tumour to a strong electric field.
  
  
  METHODS
  Here we present a 3D model of a subcutaneous tumour in a four-layer skin using a geometry-based finite element approach. Four common needle electrode configurations were studied in this paper. The study evaluated six essential factors which are important in the electrical and thermal distributions in tumour and normal tissue.
  
  
  RESULTS
  The results revealed that a hexagonal 3 × 3 geometry provides the maximum electrical coverage of the tumour, compared to other electrode configurations. However, in some cases the hexagonal 2 × 2 geometry can ablate the entire tumour with less damage to normal tissue. We found that the deeper insertion of 2- and 4-electrode geometries can lead to more damage to healthy tissue. The results also indicate that the insertion of the electrodes into tumour tissue can increase thermal damage dramatically due to existing large electrical conductivity.
  
  
  CONCLUSIONS
  These findings suggest that needle electrodes should not be placed within the tumour tissue if the goal is to prevent thermal damage. This method can be used as a trade-off between electric field coverage in tumour tissue and thermal damage to both tumour and normal tissue.
authors.affiliation: Medical Physics Department, Shahid Sadoughi University of Medical Sciences , Yazd , Iran .
authors.forename: Abolfazl
authors.initials: A
authors.lastname: Nickfarjam
authors.forename: S Mohammad P
authors.initials: SM
authors.lastname: Firoozabadi
mesh_terms: D055011:Ablation Techniques; D004553:Electric Conductivity; D004566:Electrodes; D018274:Electroporation; D020342:Finite Element Analysis; D008954:Models, Biological; D009339:Needles; D012867:Skin; D012878:Skin Neoplasms; D013814:Thermal Conductivity
keywords: Irreversible electroporation; numerical modelling; parametric study; thermal damage; tissue ablation