By Dave DeFusco

A team of researchers at UNC-Chapel Hill has developed a wireless wearable device—the Laryngeal Health Monitor—that promises to transform how neuromuscular diseases are monitored and treated, according to the study, “AI-boosted and Motion-corrected, Wireless Near-infrared Sensing System for Continuously Monitoring Laryngeal Muscles,” published in the journal PNAS.

The device, or LaHMo, can track muscle movements in the neck, providing detailed insights into conditions such as voice problems, swallowing difficulties and even post-COVID cough. The system aims to help doctors and patients monitor disease progression, evaluate treatments and improve rehabilitation programs.

“Neuromuscular disorders, which can weaken or deteriorate muscle function, are a growing health concern worldwide,” said Dr. Wubin Bai, senior author of the paper and an assistant professor in the Department of Applied Physical Sciences. “Treating these diseases is challenging, with high healthcare costs and the need for long-term care and rehabilitation.”

Currently, most muscle-tracking technologies—such as ultrasound, electromyography or mechano-acoustic sensors—either require special adhesives, provide limited data or are uncomfortable for extended use. The LaHMo platform addresses these limitations with a non-invasive, comfortable patch placed on the neck, capable of continuously monitoring muscle activity without bulky equipment. The device uses near-infrared light to penetrate deep tissue and detect muscle movement by interacting with myoglobin—a key muscle protein. Additionally, an inertial measurement unit sensor tracks the motion of the user’s head to ensure accurate measurements, even when the person moves.

The device is powered by an AI-enhanced algorithm that helps interpret the signals from the sensors. This technology can classify activities like coughing, breathing, swallowing and exercise in real time. Unlike other systems, LaHMo uses an adaptive AI model that learns quickly from the wearer, allowing it to be tailored to individuals.

“By offering biofeedback for rehabilitation exercises, the device could assist patients recovering from muscle dysfunction and provide doctors with insights into how treatments are working,” said Yihan Liu, first author of the paper and an APS Ph.D. candidate. He was joined by researchers from the UNC departments of Biomedical Engineering; Biostatistics; Computer Science; and Physics and Astronomy.

The LaHMo system is designed to monitor both intrinsic and extrinsic muscles in the neck, which play critical roles in functions like speech and swallowing. These muscles are often affected in conditions, such as dysphagia, or difficulty swallowing, and dysphonia, or voice problems. In addition, persistent coughs following COVID-19 infection have been linked to abnormal muscle activity in the throat, and LaHMo offers a way to monitor and manage these symptoms.

“Initial tests have shown that LaHMo can accurately detect muscle activities and provide real-time feedback,” said Liu. “While it has been tested in controlled environments, future studies are needed to confirm its effectiveness in real-world settings with larger patient populations.”

In the long run, LaHMo could offer more than just diagnostics. It holds promise for sports performance monitoring, rehabilitation tracking and early screening of neuromuscular conditions. The researchers hope that the technology will be integrated with other medical tools, improving treatment outcomes for a wide range of muscle disorders.

“LaHMo represents a step forward in non-invasive healthcare technology, offering patients a user-friendly way to monitor and manage their health,” said Dr. Bai. “With further testing and development, it could become an essential tool for neurological care, rehabilitation and personalized treatment in the near future.”

January 8, 2025