Optimal applicator placement in hepatic radiofrequency ablation on the basis of rare data

Abstract

In this paper, a numerical procedure to determine an optimal applicator placement for hepatic radiofrequency ablation incorporating uncertain material parameters is presented. The main focus is set on the treatment of subjective and rare data-based information. For this purpose, we employ the theory of fuzzy sets and model uncertain parameters as fuzzy quantities. While fuzzy modelling has been established in structural engineering in the recent past, it is novel in biomedical engineering. Incorporating fuzzy quantities within an optimisation task is basically innovative. In our context, fuzzy modelling allows us to determine an optimal applicator placement that maximises the therapy success under the given uncertainty conditions. The applicability of our method is demonstrated by means of an example case.

Keywords:

• radiofrequency ablation
• optimisation of applicator placement
• uncertain material parameters
• fuzziness
• fuzzy optimisation

Acknowledgements

A part of this research was supported by the German Research Foundation (DFG, project Pe 199/15-2). We would like to thank Philippe L. Pereira and Diethard Schmidt from the University Hospital of Tübingen, Germany, for supplying the CT scans that were used for the presented example as well as Susanne Zentis and Claudia Hilck from MeVis Medical Solutions for preprocessing these CT scans.