Accuracy Evaluation of an iPad Light Detection and Ranging-based Breathing Motion Measurement System Using a Breathing Motion Phantom

野寄, 修平; 二村, 昭元

doi:10.51094/jxiv.6569

##article.authors##

野寄, 修平 Department of Functional Joint Anatomy, Biomedical Engineering Laboratory, Institute of New Industry Incubation, Institute of Science Tokyo https://researchmap.jp/NoyoriShuhei
二村, 昭元 Department of Functional Joint Anatomy, Biomedical Engineering Laboratory, Institute of New Industry Incubation, Institute of Science Tokyo

DOI:

https://doi.org/10.51094/jxiv.6569

キーワード:

Breathing motion、 Non-contact measurement、 Respiratory function、 Phantom study

抄録

Objectives: We aimed to evaluate the accuracy of an iPad light detection and ranging (LiDAR)-based breathing motion measurement system using a breathing motion phantom. The system measured regional breathing motion in the chest and abdominal regions determined using body keypoints, and the measurements were compared with those obtained using an optical motion capture system.
Methods: A breathing motion phantom generated sinusoidal anterior–posterior motion under nine combinations of breathing rates (5, 10, and 15 breaths/min) and peak-to-peak motion ranges (10, 20, and 30 mm). Breathing motion was measured simultaneously using an iPad Pro with a LiDAR-based breathing motion measurement application and an optical motion capture system. Each condition was measured five times in the chest and abdominal regions. The measurement accuracy was assessed using the mean absolute error (MAE), root mean square error (RMSE), and signal-to-noise ratio (SNR).
Results: MAE was 0.39–0.69 mm and 0.33–0.79 mm and RMSE was 0.47–0.88 mm and 0.42–0.95 mm for the chest and abdomen, respectively. The largest errors were observed at 15 breaths/min with a 30-mm peak-to-peak range. SNR was 16.96–25.46 dB for the chest and 16.66–24.26 dB for the abdomen.
Conclusions: The iPad LiDAR-based breathing motion measurement system demonstrated submillimeter measurement errors under the tested breathing conditions. These findings support the feasibility of using an iPad-based LiDAR system for non-contact measurement of regional breathing motions. Further validation in human participants with more physiologically representative breathing patterns and environmental conditions is required.

利益相反に関する開示

The authors are affiliated with a joint research department established by JA Kyosai Research Institute and the Institute of Science Tokyo. AN is an unpaid director of Vitalizar Inc. The BREVI iPad application was provided free of charge by Vitalizar Inc.

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