Vol 22, No 1 (2018) > Mini Conference >

Coax-Fed Dipole-Type Applicator for Hepatic Cancer RF Ablation

Basari Basari 1 , Aditya Rakhmadi 1 , Kazuyuki Saito 2

Affiliations:

  1. Department of Electrical Engineering, Faculty of Engineering, Universitas Indonesia, Indonesia
  2. Center for Frontier Medical Engineering, Chiba University

 

Abstract: Up to now, cancer is the third most mortality cause in the world. Cancer is one of the health problems that is very difficult to be detected and cured as well. This allows us to study a treatment method for curing cancer cell by using RF ablation treatment method. RF ablation therapy is a cancer killing method by electromagnetically heating up the cancer cell. The treatment uses an applicator that is inserted into the body for heating the cells. The cancer cells are exposed to the temperature more than 60C in short duration (few second to few minutes) allowing to cell destruction locally. In order to have good treatment, a minimally invasive method is selected, so thus good local temperature distribution inside the cancer cells can be achieved. In this paper, a coax-fed dipole-type applicator is proposed for interstitial irradiation technique aiming at hepatic cell treatment. The applicator design is conducted by simulation in CST Microwave Studio in order to obtain appropiate size at operating frequency of 2.45 GHz. We also consider to localize the ablation area by designing the tip of applicator in such a way the main EM radiation will locally exist around the tip of the applicator. The proposed applicator is inserted into a simple phantom model representing an adult human body in which normal and cancerous liver cells. Both simulated and measured results show that the proposed applicator is able to operate at center frequency of 2.45 GHz with blood droplet-type ablation zone. The temperature around the cancer cell by 60⁰C can be achieved by simulation. Moreover, in order to increase the ablation zone for larger tumor cell, square four-array applicator is analyzed. The simulated results show a reasonable wider local ablation area can be achieved.
Keywords: Ablation zone; applicator; coax-fed dipole applicator; hepatic cancer; RF ablation
Published at: Vol 22, No 1 (2018) pages: 46-52
DOI:

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