Applying a repetitive time‐reversal method to reduce input power of a wearable hyperthermia applicator for breast cancer treatment

Abstract

In this article, a hyperthermia healing system is presented for cancer treatment. To alleviate most of the microwave hyperthermia systems problems, such as high input power, complicated beamforming method, unwanted hot spots for superficial tumors, and bulky profile, a simple repetitive time‐reversal method is proposed to design a low power wearable hyperthermia applicator with low hotspots at 915 MHz. The objective of this algorithm is to obtin the desired focusing by the minimum possible number of antennas in an appropriate time and minimum required input power. In this paper, first, a symmetric 11‐element patch array is considered. Then, by applying a repetitive time‐reversal method, the number of elements decreases to 7 for deep and 4 for both superficial and intermediate tumors, respectively. The steady‐state temperature/specific absorption rate focusing and transient thermal analysis are investigated in CST MWS and COMSOL, respectively. The target temperature of 43°C is met after less than 10 minutes. The focusing diameter size varies between 1 and 2 cm depending on the number of elements and arrangements considered for different tumors. Compared to literature, this applicator needs very low input power, produces less unwanted hotspots, improves pationt comfort, reduces treatment cost which all leads to patient treatment persistency. Moreover, it does not need any complicated beamforming method.

A phased array applicator based on open ridged‐waveguide antenna for microwave hyperthermia

“…Furthermore, the optimum phase and amplitude of each element in the array need to be determined so that the focal point is steered on the target and that hot‐spot formations in the healthy tissue are suppressed. Several beamforming methods have been proposed in the literature among which we count the generalized eigenvalue problem, 8 time reversal (TR), 9,10 particle swarm optimization (PSO), 11 and focusing via constrained optimization 12 …”

Microwave Hyperthermia Application with Bioimplant Single Slot Coaxial Antenna Design for Mouse Breast Cancer Treatment

“…For instance, a related study was only conducted on the rate of cooking the egg whites by volume, and the SAR values of the antenna immersed in a bowl filled with egg white in a simple but effective method [31]. As a more effective method than egg white, few publications work on these artificial fluids by creating tissue fluid using an artificial biological tissue (phantom model) [28,29,32,33]. The study, which can be considered as a higher level one than the tissue fluid, is to work on organs such as kidneys, spleen, liver, or organ parts [34][35][36].…”