A Preliminary Study on Detecting Tumor Boundaries with an Open-Ended Coaxial Probe

Various methods are used to determine the boundaries of malignant tissues. Frozen section analysis (FSA) is the most popular technique to determine tumour boundaries during surgical operation. In this study, open-ended coaxial probe (OECP) method was used to decide tumour boundaries according to dielectric properties. Experiments were performed with OECP on a heterogeneous phantom containing breast fat and tumour-mimicking materials. In heterogeneous tissue with undefined boundaries (breast fat-tumour), since fat and tumour have markedly different dielectric properties, the tumour boundary can be approximated by measuring the dielectric property. The fat and tumour phantoms have epsilon'= 8.45 and epsilon'= 47.09 at 5 GHz, respectively. However, the measured relative permittivity of the tumour boundary is epsilon'= 23.85. These experimental results (dielectric property measurements and distance between probe and tumor centres) were implemented to MATLAB to model the heterogeneous phantom (fat and tumor).