AGAR PHANTOM DEVELOPMENT AS A TEST OBJECT ON RADIO FREQUENCY ABLATION USING BIPOLAR ELECTRODE

• Main Author: FAUZIAH AKASUM - NIM. 23815006 , GINA
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/22282
• Institution: Institut Teknologi Bandung

Radio frequency ablation is one of the thermal therapies that use heat generated by high-frequency electricity to kill cancer tissue. Therapy planning is a crucial step to obtain the dose of therapy according to the conditions of cancer tissue. Therapy planning in Indonesia is highly dependent on the experience of the surgeon. A simulation is required that can describe the condition of cancer in the test object (phantom) that resembles the biological tissue characteristics. <br /> <br /> <br /> Phantom was made with 2% agar, 0.3% NaCl and a heat-sensitive ink. The examination of the thermal conductivity (k), electrical conductivity (&#963;) and density (&#961;) are performed with instruments that have been designed at the lab scale. Fantom has a k value of 0.67 W/m.K, &#963; of 0.02129 S/m and &#961; of 998 kg/m3. The value of the phantom parameter was designed to the simulation model and the solution was calculated by the finite element method. <br /> <br /> <br /> Radio frequency ablation was performed on phantom using bipolar electrodes. The output voltage of a local generator of 160V and a frequency of 250 kHz was applied for 120 seconds. Two important parameters that can be seen in biological process was coagulation volume and temperature distribution. Experimental results indicate the dominant heat generation occurred in the area between electrodes. The measurement using K type thermocouple showed that temperature at the point between electrode reaching 50oC and temperature at 4 mm spacing point only increase up to 32oC. This temperature rising was observed on two cross sections, i.e. on a parallel cross-section of electrodes and perpendicular to electrodes. The coagulation volume is ellipsoid with changes color to white area in the phantom. This color change occurs in the range 50-58oC according to the limit of coagulation on the biological tissue (50-60oC). <br /> <br /> <br /> The experimental temperature measurement compared to simulation's result the RMSE value of 4.14 at the point between the electrode and 1.99 at the point 4 mm from the electrode. The ablation volume generated from the experiment is 1741,69 mm3 the volume of ablation of simulation result is 1218,91 mm3.