Design Development of Electrical Capacitance Volume Tomography (ECVT) Sensor for Breast Cancer Scanner
Heni Sumarti, MS Thesis, Dept. of Physics, University of Indonesia, 2014
In this study, we proposed new sensor designs for diagnosing breast cancer using capacitance measurement methods that have been developed previously called Electrical Capacitance Volume Tomography (ECVT). The technique works based on the fact that cancer tissues permittivity is greater than normal tissues’. The half-sphere sensor design which is developed consists of triangle and rectangle-shape electrodes. The sensor is able to detect the concentration of cancer. The comparison of ECVT image with ultrasound and mammography shows a correlation. However, the image resolution of the sensor is not good enough. Some of the factors that determine image resolution and accuracy from capacitance tomography sensors are the shape of capacitance electrode plate and the arrangement. We have designed three sensors using combination of electrode shapes. The electrode shapes are pentagonal, hexagonal, triangle and rectangular which are arranged on a vessel that is similar to breast geometry. The new design is compared with the old design. The simulation result showed that the best design is 20 electrodes with combined hexagonal and pentagonal shaped. The experiment used phantom which is made from silicon rubber as normal tissue in which there are cow bone as cancer tissue or water as cystic or bloods. The result was compared with micro-CT to verify that the system which was used is good to show the final result in acceptable range.