No 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.

Case reports indicate that magnets in smartphones could be a source of electromagnetic interference (EMI) for active implantable medical devices (AIMD), which could lead to device malfunction, compromising patient safety. Recognizing this challenge, we implemented a high-fidelity 3D magnetic field mapping (spatial resolution 1 mm) setup using a three-axis Hall probe and teslameter, controlled by a robot (COSI Measure). With this setup, we examined the stray magnetic field of an iPhone 13 Pro, iPhone 12, and MagSafe charger to identify sources of magnetic fields for the accurate risk assessment of potential interferences with AIMDs. Our measurements revealed that the stray fields of the annular array of magnets, the wide-angle camera, and the speaker of the smartphones exceeded the 1 mT limit defined by ISO 14117:2019. Our data-driven safety recommendation is that an iPhone 13 Pro should be kept at least 25 mm away from an AIMD to protect it from unwanted EMI interactions. Our study addresses safety concerns due to potential device–device interactions between smartphones and AIMDs and will help to define data-driven safety guidelines. We encourage vendors of electronic consumer products (ECP) to provide information on the magnetic fields of their products and advocate for the inclusion of smartphones in the risk assessment of EMI with AIMDs.