Synthetic aperture-based UWB imaging system for detection of urine accumulation in human bladder

Abstract

This paper presents a synthetic aperture-based UWB radar imaging system. The goal is to detect the urine accumulation in the human bladder. To verify this radar concept a bladder model with various human tissues including realistic dielectric properties is simulated. Two scan configurations with different antenna positions are used to investigate the influence of the synthetic aperture length and position number in the microwave images. To generate the imaging results, Delay and Sum algorithm together with coherent weighting is applied. The achieved imaging results demonstrate the possibility of detecting the position and volume of urine in the human bladder and therefore the potential application of this radar imaging system in the clinics for diagnosis purposes.I.

Proof-of-Concept of Microwave-Based Bladder State Detection Using Realistic Pelvic Models

“…Further, as the bladder fills with urine (which has higher dielectric properties than the bulk background tissues) it provides an increasing dielectric change in the pelvic region, leading to a growing target which is expected to modify the propagation of MW signals [6] . Some very preliminary studies on using MW-based approaches for bladder state detection have investigated the feasibility of this idea and shown promise; however, they have utilized simplified models having limited realism [7] , [8] , [9] , [10] , [11] , [12] , [13] , [14] , [15] , [16] (see Fig. 1 ).…”

“… Most advanced layered models studied to date: (left) flat multi-layered structure (this one includes six tissue types, from [14] ); and (right) elliptically-shaped multi-layered structure (including four tissue types, from [13] ). The black arrows indicate variable urine volumes considered.…”

“…Further, research with these models have almost always included studies of changing the urine volume (i.e., changing the 2D or 3D dimensions of the bladder), but none to date have included the impact of uncertainty in urine properties. Additionally, no studies to date were conducted with antennas that could be practically used in a MW bladder monitor as they were focused on end-fire (e.g., Vivaldi-type) antenna designs [13] , [14] , [15] .…”