A wearable ultrasound armband uses a focused piezoelectric transducer and acoustic hydrogel to deliver low-intensity ultrasound pulses to peripheral nerves, noninvasively reducing chronic and neuropathic pain for several hours.
Peripheral nerve stimulation has emerged as a promising field in pain management, seeking to address the growing global burden of chronic and neuropathic pain. Traditional pharmacological treatments often rely on opioids, which carry significant risks of dependency and systemic side effects. Meanwhile, non‐invasive methods such as transcutaneous electrical nerve stimulation (TENS) offer safer alternatives but suffer from limited tissue penetration and imprecise targeting of deep nerve structures. As the demand for comfortable, user‐friendly, and effective pain relief solutions increases, there is a clear need for technologies that can deliver focused, long‐lasting neuromodulation without invasive procedures or systemic medication. Existing neuromodulation approaches face several critical limitations. Implantable nerve stimulators require surgical placement and maintenance, creating barriers in cost, patient compliance, and risk of infection. Surface electrical stimulators lack the spatial precision to selectively activate specific peripheral fibers, often producing inconsistent analgesic effects. Conventional focused ultrasound platforms offer improved depth control but are bulky, stationary, and dependent on cumbersome coupling gels that degrade over time. These systems typically demand specialist operation, limiting their use outside clinical settings and hindering continuous, at‐home pain management.
The wearable armband incorporates a 25 mm concave piezoelectric transducer (650 kHz, 20 mm radius of curvature) embedded within a 3D-printed polylactic acid housing and coupled to the skin via a biocompatible acoustic hydrogel sheet. By focusing ultrasound energy at a 10–20 mm depth with a 3.5 mm axial and 18.5 mm lateral beam profile, the system delivers 136 bursts of 200 ms duration at 100 Hz (50 % duty cycle) over a five-minute session. A microcontroller triggers the stimulation protocol through a commercial ultrasound platform, precisely targeting the median nerve located 1.5–2 cm beneath the skin. This approach distinguishes itself through its integrated wearable format and sustained couplant stability, eliminating the need for repeated gel applications while ensuring efficient ultrasound transmission with minimal attenuation (~5 %). The concave transducer’s precise focus depth and beam profile allow targeted neuromodulation of peripheral nerves with millimeter accuracy, and the biocompatible hydrogel adheres securely for long-term use. Unlike traditional therapies, this system offers a non-invasive, opioid-free method for pain management with demonstrated analgesic effects lasting up to eight hours post-session. Its customizable 3D-printed housing and microcontroller-driven protocol enable easy adaptation to different nerve targets and user comfort.
• Non-invasive, drug-free chronic and neuropathic pain relief • Targeted low-intensity focused ultrasound stimulation for precise nerve modulation • Portable, wearable design enabling comfortable long-term use • Biocompatible hydrogel ensures strong skin adhesion and efficient ultrasound coupling • Demonstrated increases in pain thresholds lasting 8–9 hours post-treatment • Stable performance over weeks without repeated gel application • Reduces reliance on opioids, minimizing addiction risk • Operates within FDA safety limits for ultrasound exposure
• Chronic pain management • Neuropathic pain therapy • Postoperative pain relief • Sports injury recovery • Physical therapy adjunct
A wearable armband integrates a 25 mm‐diameter, 20 mm‐radius‐of‐curvature PZT transducer (650 kHz) in a 3D‐printed housing with biocompatible acoustic hydrogel for skin coupling. It focuses ultrasound at 10–20 mm depth (3.5 mm axial × 18.5 mm lateral beam) and delivers 136 bursts of 200 ms at 100 Hz (50% duty) over five minutes via a microcontroller‐triggered system targeting the median nerve at 1.5–2 cm depth.
U.S. Provisional application filed