Open-ended coaxial probe measurements for breast cancer detection

Abstract

We have simulated and experimentally tested a coaxial probe measuring system to be used in distinguishing between normal (healthy) breast tissue and cancerous (often malignant) breast tissue. The system employs commercially available components including an Agilent 8363B phase network analyzer (PNA) and an Agilent 85070D dielectric probe. Instead of the Agilent software three material calibration technique, we propose a four material calibration method across the frequency range of 3-17 GHz for more robust measurements of the complex permittivity. Experimental results on human and snake tissues show the non-homogeneous nature of biological tissues and also illuminate the dependence of complex permittivity on tissue temperature. Building upon the differences and also the variation seen in complex permittivity in literature between normal and cancerous breast tissue across this frequency range, we propose a technique which utilizes a neural network where multiple measurements are input in making the final decision on whether or not the tissue under test is cancerous. Simulation results using Ansoft HFSS are provided here and show the potential of microwave diagnosis of breast cancer.Index Terms -Open-ended coaxial probe, breast cancer detection, complex permittivity, neural networks.

Meme Kanseri Tespitinde Mikrodalgaların Önemi ve Kanserli/Sağlıklı Meme Dokularının Yapay Zeka Algoritmaları ile Tanımlanabilmesi

“…Normal meme dokusu ile kanserli doku arasındaki ayrımı kullanarak bir koaksiyel prob ölçüm sistemiyle test yapılmıştır [18]. Aynı zamanda Şekil 7'de de gösterildiği gibi çalışmalarını bir simülasyon ortamında da gerçekleştirmişlerdir.…”

“…Literatürde yer alan ve bu konuda yapılan çalışmalar, mikrodalga ile görüntülemenin, meme kanseri tespiti için diğe r yöntemlere göre daha Şekil 8. Koaksiyel prob ölçüm sisteminin blok şeması [18] ucuz, güvenli bir teknik olduğunu göstermektedir ve çalışmalar devam etmektedir.…”

Determining the Relative Permittivity of Deep Embedded Biological Tissues

“…Furthermore, they do not allow for continuous monitoring as they are not body-worn. Probe methods do provide accurate approximation of the dielectric constant [1], [2], but require direct access to the specimen. Therefore, they are only suitable for in vitro applications.…”

“…We propose to represent as a weighted sum of the scattering parameters measured from the multiprobe sensor at ports , where refers to the total number of measurement ports. That is (1) where is the port number, refers to the weights (to be calculated) at each port, and are the scattering parameters read across the th port. In effect, the weights in (1) need be "trained" to minimize the error in extracting , basically calibrating the system.…”

“…To do so, we proceeded to first collect simulated data using a known inner tissue in the presence of varying outer tissues (varying thickness and dielectric values). Concurrently, we collected the values for these different configurations and constructed a system of equations that enforces (1). Each row in this system's matrix is associated with the collected scattering parameters ( , ) for a single outer-layer condition.…”