Implants, Imaging & Innovation: The Expanding Medical Use of Microwave Technology

By John Oncea, Editor

Microwave tech is revolutionizing healthcare from diagnostics to wireless implants by enabling noninvasive, connected, and efficient medical and life science solutions.

Microwaves have made their presence felt across multiple industries, perhaps none more so than the medical and life sciences fields. With frequencies ranging from 300 MHz to 300 GHz, the use of microwaves in these two fields is rapidly expanding, influenced by technological innovations and a drive toward more efficient, precise, and noninvasive solutions.

According to IEEE, current microwave applications include medical diagnostics and imaging, in which microwaves enable noninvasive detection of diseases such as breast cancer. Improvements in sensor and antenna technologies are enabling more compact, affordable diagnostic tools. In addition, microwave radiometry detects temperature variations within the body, offering functional imaging distinct from infrared thermography.

In therapeutics, IEEE writes, microwave ablation is used to treat tumors and abnormal tissues using targeted heating, and biomedical radar technologies (short-range microwave sensing) are applied in vital sign monitoring and non-contact patient sensing, important in emergency medicine and long-term health monitoring.

Finally, Royal Society Publishing adds, microwave heating is employed in sterilization and sample processing for rapid sterilization in hospitals and laboratories due to its efficiency and ability to target biological contaminants.

Here, we take a closer look at the interplay between microwaves and the devices that utilize wireless communication technologies like Bluetooth or Wi-Fi to transmit data or receive commands from external devices.

The Use Of Microwaves In The Medical And Life Sciences

As noted earlier, the use of microwaves is driving emerging applications in the medical and life sciences fields, including non-thermal biological interactions, where there is growing interest in exploiting non-thermal microwave effects, such as influencing cellular or molecular processes without significant temperature rise. Potential future applications may include precision medicine interventions at the cellular level. Other examples include:

• Machine learning and smart systems that are combined with microwave sensing technologies for rapid disease detection, personalized therapy, and health analytics
• Point-of-care and remote health monitoring through the development of compact, remote, and noninvasive diagnostic platforms based on microwave technology that will support telemedicine and home-based healthcare, expanding access and reducing healthcare costs
• Multi-physics and hybrid modalities, in which combining microwave imaging/sensing with other acoustic, thermal, and electromagnetic modalities enhances sensitivity and specificity, helping develop new algorithms for better image reconstruction and noise suppression

An additional technology benefiting from microwaves is wireless implantable devices (IMDs) that are used for a variety of applications, including monitoring vital signs, delivering therapies, and managing chronic conditions. Examples include pacemakers, implantable cardioverter defibrillators (ICDs), deep brain stimulators, insulin pumps, and glucose monitors.

What Are IMDs

IMDs represent a rapidly advancing field, leveraging wireless power transfer (WPT) and wireless communication technologies to enable minimally invasive, intelligent healthcare solutions. Key WPT techniques include inductive coupling (using coils), magnetic resonance coupling, capacitive coupling, and acoustic (ultrasound) and optical power transfer, according to MDPI.

Each approach varies in efficiency, safety, and depth of penetration within the body. For example, inductive and magnetic resonance methods are common for shallow implants, while acoustic and optical methods are being explored for deeper implants.

The use of wireless communication comes via the use of RF protocols, including Bluetooth Low Energy, to transmit data such as physiological signals or device status to external receivers (e.g., smartphones, clinical monitors) for remote patient monitoring, Nature Communications writes.

Applications of IMDs in the medical and life sciences fields include wireless pacemakers, defibrillators, neurostimulators for pain management, continuous glucose monitors and insulin pumps, drug delivery systems, and smart stents and biosensors for real-time diagnostics and feedback.

Then there are emerging innovations, starting with direct implant-to-implant networking. Recent breakthroughs include the use of metamaterial textiles that facilitate direct communication between multiple implants within the body without relaying signals through external devices. This enhances reliability and enables coordinated, closed-loop therapies such as syncronizing heart rate monitors with nerve stimulators.

Advances in wireless powering have accelerated the development of battery-free IMDs, minimizing risk and reducing device size, while progress in microelectronics is producing ever-smaller, multi-functional implants capable of complex sensing, actuation, and communication, according to Wiley Advanced. Finally, technologies like dual-band rectennas are being developed to efficiently power devices located deep within the body at medically relevant frequencies (e.g., 0.915 and 2.45 GHz).

Challenges And Considerations

As with any technology, there are challenges to overcome, including safety. WPT systems must avoid excessive tissue heating. The optimal frequency and intensity are carefully chosen to maximize efficiency and comply with safety standards.

In addition, transferring sufficient energy, especially to deep implants, is difficult and constrained by tissue properties and regulatory limits. Reliability is an issue as well, and maintaining high data rates and stable connections in the body’s complex and variable environment remains an area of active research.

Wireless IMDs are transforming healthcare by offering safe, dependable, and patient-friendly solutions for monitoring, therapy, and disease management. Continued progress in wireless energy transfer, communication, and networking technologies is driving the next generation of intelligent, interconnected IMDs.