title: Computer modeling of electrical and thermal performance during bipolar pulsed radiofrequency for pain relief.
abstract: OBJECTIVE
  Pulsed RF (PRF) is a nonablative technique for treating neuropathic pain. Bipolar PRF application is currently aimed at creating a "strip lesion" to connect the electrode tips; however, the electrical and thermal performance during bipolar PRF is currently unknown. The objective of this paper was to study the temperature and electric field distributions during bipolar PRF.
  
  
  METHODS
  The authors developed computer models to study temperature and electric field distributions during bipolar PRF and to assess the possible ablative thermal effect caused by the accumulated temperature spikes, along with any possible electroporation effects caused by the electrical field. The authors also modeled the bipolar ablative mode, known as bipolar Continuous Radiofrequency (CRF), in order to compare both techniques.
  
  
  RESULTS
  There were important differences between CRF and PRF in terms of electrical and thermal performance. In bipolar CRF: (1) the initial temperature of the tissue impacts on temperature progress and hence on the thermal lesion dimension; and (2) at 37 °C, 6-min of bipolar CRF creates a strip thermal lesion between the electrodes when these are separated by a distance of up to 20 mm. In bipolar PRF: (1) an interelectrode distance shorter than 5 mm produces thermal damage (i.e., ablative effect) in the intervening tissue after 6 min of bipolar RF; and (2) the possible electroporation effect (electric fields higher than 150 kV m(-1)) would be exclusively circumscribed to a very small zone of tissue around the electrode tip.
  
  
  CONCLUSIONS
  The results suggest that (1) the clinical parameters considered to be suitable for bipolar CRF should not necessarily be considered valid for bipolar PRF, and vice versa; and (2) the ablative effect of the CRF mode is mainly due to its much greater level of delivered energy than is the case in PRF, and therefore at same applied energy levels, CRF, and PRF are expected to result in same outcomes in terms of thermal damage zone dimension.
authors.affiliation: Instituto de Investigación Interuniversitario en Bioingeniería y Tecnología Orientada al Ser Humano, Universitat Politècnica de València, Valencia 46022, Spain.
authors.forename: Juan J
authors.initials: JJ
authors.lastname: Pérez
authors.affiliation: Pain Unit and Department of Anesthesia and Critical Care, Clínica Universidad de Navarra, University of Navarra, Pamplona 31008, Spain.
authors.forename: Juan J
authors.initials: JJ
authors.lastname: Pérez-Cajaraville
authors.affiliation: Neurotherm Spain, Barcelona 08303, Spain.
authors.forename: Víctor
authors.initials: V
authors.lastname: Muñoz
authors.affiliation: Biomedical Synergy, Electronic Engineering Department, Universitat Politècnica de València 46022, Spain.
authors.forename: Enrique
authors.initials: E
authors.lastname: Berjano
mesh_terms: D000465:Algorithms; D003198:Computer Simulation; D004599:Electric Stimulation Therapy / Q000295:instrumentation / Q000379:methods*; D004560:Electricity; D018274:Electroporation; D008099:Liver / Q000503:physiopathology; D009437:Neuralgia / Q000628:therapy*; D059408:Pain Management / Q000295:instrumentation / Q000379:methods; D061208:Pulsed Radiofrequency Treatment / Q000295:instrumentation / Q000379:methods*; D013696:Temperature