Share Email Print

Proceedings Paper

Noncontact sphygmomanometer based on pulse-wave transit time between the face and hand
Author(s): Kazuya Nakano; Takashi Ohnishi; Izumi Nishidate; Hideaki Haneishi
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

Systolic blood pressure (SBP) is highly sensitive to various factors such as psychological stress, and hence its continuous monitoring is essential to evaluate different health conditions. However, conventional sphygmomanometers cannot continuously measure SBP given the time-consuming setup based on a pressure cuff. Moreover, continuous biological signal monitoring is more comfortable when no sensors are attached. A solution for continuous SBP estimation is based on pulse transit time (PTT), which determines the time difference between two pulse waves at different body parts. In previous studies, we successfully measured the PTT using a contactless setup composed by two digital color cameras recording the face and hand of subjects. Then, the acquired images were transformed into blood volume by combining multiple regression analysis and a Monte Carlo method. As a result, the delay among images allowed to determine the PPT from pulse waves. In this study, we simultaneously measured SBP and PTT by using a sphygmomanometer and the two cameras, respectively. We evaluated SBP increases (i.e., stressful situations) and the corresponding PPT by asking participants to either grasp a handgrip or momentarily interrupting breath. We also determined the SBP and PTT without asking for such exercises. Comparison results show that the mean PTT under stress was significantly lower than that without stress, which is consistent with an increased SBP. Finally, we related the SBP and PTT by a nonlinear formula with a coefficient of determination of 0.59, thus confirming the effectiveness of the proposed system.

Paper Details

Date Published: 20 February 2018
PDF: 8 pages
Proc. SPIE 10501, Optical Diagnostics and Sensing XVIII: Toward Point-of-Care Diagnostics, 1050110 (20 February 2018);
Show Author Affiliations
Kazuya Nakano, Chiba Univ. (Japan)
Takashi Ohnishi, Chiba Univ. (Japan)
Izumi Nishidate, Tokyo Univ. of Agriculture and Technology (Japan)
Hideaki Haneishi, Chiba Univ. (Japan)

Published in SPIE Proceedings Vol. 10501:
Optical Diagnostics and Sensing XVIII: Toward Point-of-Care Diagnostics
Gerard L. Coté, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?