Feasibility of Using Wideband Microwave System for Non-Invasive Detection and Monitoring of Pulmonary Oedema

Abstract

Pulmonary oedema is a common manifestation of various fatal diseases that can be caused by cardiac or non-cardiac syndromes. The accumulated fluid has a considerably higher dielectric constant compared to lungs’ tissues, and can thus be detected using microwave techniques. Therefore, a non-invasive microwave system for the early detection of pulmonary oedema is presented. It employs a platform in the form of foam-based bed that contains two linear arrays of wideband antennas covering the band 0.7–1 GHz. The platform is designed such that during the tests, the subject lays on the bed with the back of the torso facing the antenna arrays. The antennas are controlled using a switching network that is connected to a compact network analyzer. A novel frequency-based imaging algorithm is used to process the recorded signals and generate an image of the torso showing any accumulated fluids in the lungs. The system is verified on an artificial torso phantom, and animal organs. As a feasibility study, preclinical tests are conducted on healthy subjects to determinate the type of obtained images, the statistics and threshold levels of their intensity to differentiate between healthy and unhealthy subjects.

<p>A Novel Radiofrequency Device to Monitor Changes in Pulmonary Fluid in Dialysis Patients</p>

“… 3 Furthermore, measurement of lung fluid using radiofrequency (RF) measurements may serve as a viable option to remotely monitor patients with heart failure, and RF when delivered at the optimum frequency range offers fluid detection capabilities in the lungs. 4 Detection of early fluid changes in CKD and HF patients may potentially assist with remote patient management.…”

Three-Dimensional Electromagnetic Torso Scanner

“…This adds to the complexity of the design, weight of the system and its portability. Almost all existing systems rely on a priori information regarding the healthy state/profile of the imaged domain as a reference to help identify pathology in imaging [11,23,34,35]. While this can be achieved in theory, it is an impractical approach from a realistic application point of view.…”

Three-dimensional simplified electrodynamic model of the human chest

“…Every year in medicine, radio and microwave radiation is used more actively [3]. The main areas of application of microwave radiation are measuring the fluid content in human tissues, detecting breast cancer, studying the movement of the arterial wall, observing cardiac and nervous activity, as well as non-invasive therapy by heating tissues when exposed to microwave radiation [4][5][6].…”