liu.seSearch for publications in DiVA
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Comparison between a detailed and a simplified finite element model of radio-frequency lesioning in the brain
Linköping University, Department of Biomedical Engineering, Biomedical Instrumentation. Linköping University, The Institute of Technology. (MINT)
Linköping University, Department of Biomedical Engineering, Biomedical Instrumentation. Linköping University, The Institute of Technology.
Linköping University, Department of Management and Engineering, Applied Thermodynamics and Fluid Mechanics. Linköping University, The Institute of Technology.
Linköping University, Department of Management and Engineering, Applied Thermodynamics and Fluid Mechanics. Linköping University, The Institute of Technology.
Show others and affiliations
2004 (English)In: 26th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, San Fransisco, USA, 2004, Vol. 4, 2510-2513 p.Conference paper, Published paper (Refereed)
Abstract [en]

A detailed and a simplified model of a lesioning electrode was made using the finite element method. 15 simulations of the lesioning procedure were performed for each model and the resulting lesion volumes were compared in order to investigate if the simplified model is adequate. The simplified model resulted in a very slight overestimation of the volume compared to the detailed model. It was thus concluded that the simplified model is adequate for simulations.

Place, publisher, year, edition, pages
2004. Vol. 4, 2510-2513 p.
National Category
Engineering and Technology
Identifiers
URN: urn:nbn:se:liu:diva-13995DOI: 10.1109/IEMBS.2004.1403723OAI: oai:DiVA.org:liu-13995DiVA: diva2:22412
Available from: 2006-09-25 Created: 2006-09-25 Last updated: 2017-02-22Bibliographically approved
In thesis
1. Thermocoagulation in Deep Brain Structures: Modelling, simulation and experimental study of radio-frequency lesioning
Open this publication in new window or tab >>Thermocoagulation in Deep Brain Structures: Modelling, simulation and experimental study of radio-frequency lesioning
2006 (English)Licentiate thesis, comprehensive summary (Other academic)
Abstract [en]

Radio-frequency (RF) lesioning is a method utilising high frequency currents for thermal coagulation of pathological tissue or signal pathways. The current is delivered from an electrode with a temperature sensor, permitting control of the current at a desired target temperature. In the brain RF-lesioning can e.g. be used for severe chronic pain and movement disorders such as Parkinson’s disease. This thesis focuses on modelling and simulation with the aim of gaining better understanding and predictability of the lesioning process in deep brain structures. The finite element method (FEM) together with experimental comparisons was used to study the effects of electrode dimensions, electrode target temperature, electric and thermal conductivity of the brain tissue, blood perfusion and cerebrospinal fluid (CSF) filled cysts. Equations for steady current, thermal transport and incompressible flow were used together with statistical factorial design and regression analysis for this purpose.

Increased target temperature, electrode tip length and electrode diameter increased the simulated lesion size, which is in accordance with experimental results. The influence of blood perfusion, modelled as an increase in thermal conductivity in non-coagulated tissue, gave smaller simulated lesions with increasing blood perfusion as heat was more efficiently conducted from the rim of the lesion. If no consideration was taken to the coagulation the lesion became larger with increased thermal conductivity instead, as the increase in conducted heat was compensated for through an increased power output in order to maintain the target temperature. Simulated lesions corresponded well to experimental in-vivo lesions.

The electric conductivity in a homogeneous surrounding had little impact on lesion development. However this was not valid for a heterogeneous surrounding. CSF-filled cysts have a much higher electric conductivity than brain tissue focussing the current to them if the electrode tip is in contact with both. Heating of CSF can also cause considerable convective flow and as a result a very efficient heat transfer. This affected simulated as well as experimental lesion sizes and shapes resulting in both very large lesions if sufficient power compared to the cysts size was supplied and very small lesions if the power was low, mitigating the heat over a large volume.

In conclusion especially blood perfusion and CSF can greatly affect the lesioning process and appear to be important to consider when planning surgical procedures. Hopefully this thesis will help improve knowledge about and predictability of clinical lesioning.

Place, publisher, year, edition, pages
Institutionen för medicinsk teknik, 2006. 44 p.
Series
Linköping Studies in Science and Technology. Thesis, ISSN 0280-7971 ; 1267
Keyword
Neurosurgery, Radiofrequency ablation, Finite element method, Blood perfusion, Cerebrospinal fluid, Free convection
National Category
Surgery
Identifiers
urn:nbn:se:liu:diva-7406 (URN)91-85643-98-X (ISBN)
Presentation
2006-10-12, IMT 1, plan 13, Campus US, Linköpings universitet, Linköping, 00:00 (English)
Opponent
Supervisors
Available from: 2006-09-25 Created: 2006-09-25 Last updated: 2017-02-16Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textLink to Licentiate Thesis

Authority records BETA

Johansson, Johannes D.Eriksson, OlaWren, JoakimLoyd, DanWårdell, Karin

Search in DiVA

By author/editor
Johansson, Johannes D.Eriksson, OlaWren, JoakimLoyd, DanWårdell, Karin
By organisation
Biomedical InstrumentationThe Institute of TechnologyApplied Thermodynamics and Fluid Mechanics
Engineering and Technology

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 571 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf