Presentation Information
[B-19-22]Evaluation of Venous Thrombosis Detection System Using a Trans-nail PPG Sensor
◎△Yukino Sakurai1, Aoi Kataura1, Yuqi Duan1, Ryotaro Kawashima1, Kotaro Torazawa1, Suzuki Akihiro1, Pattaramon Thianmontri1, Takafumi Fukushima1, Koji Kiyoyama2, Tetsu Tanaka1 (1. Touhoku Univ., 2. Nagasaki Inst. of Applied Science)
Keywords:
PPG,VTE
This study proposes and evaluates a non-invasive wearable system for daily venous thromboembolism (VTE) screening in non-medical environments, combining a trans-nail photoplethysmography (PPG) sensor on the big toe nail with Reservoir Computing (RC). While conventional lower-limb PPG devices requiring calf attachment present challenges regarding wearability and long-term comfort, this study utilizes a trans-nail PPG sensor offering superior wearability and signal quality.The proposed system inputs PPG signals into a microcontroller unit (MCU) for real-time waveform classification using RC—a low-cost neural network suitable for edge devices—and transmits VTE risk alerts to a terminal. The sensor module comprises a photodiode, a measurement circuit, and an LED driving circuit. To evaluate feasibility, VTE-induced venous congestion was simulated using a pneumatic calf cuff at 0, 100, and 150 mmHg while subjects performed leg exercises. The RC successfully classified the three states, demonstrating that the trans-nail PPG and RC-based system is highly effective for continuous thrombosis risk screening in daily-life settings.