As many medical technologies continue to miniaturize, the task of accurately measuring blood pressure still requires a cumbersome upper-arm cuff. Scientists at the University of Toronto and Hangzhou Normal University in China have now shown that it may be possible to use existing smartphones to measure blood pressure.
Their approach relies on noticing slight changes in the optical characteristics of the skin from a few seconds of a video of the face. Called transdermal optical imaging, the technology was about 95% accurate when compared with clinical cuff-based blood pressure measurement, both for systolic and diastolic numbers. So far, this has only been tried with healthy patients within fairly normal blood pressure ranges, so further study is needed to validate the findings on larger and more varied samples of people.
Moreover, the study was conducted under highly controlled settings with even illumination, few shadows, and a stationary camera. It will be interesting to see if it will be possible to maintain accuracy when measuring blood pressure using transdermal optical imaging in less controlled environments.
Study in journal Circulation: Cardiovascular Imaging: Smartphone-Based Blood Pressure Measurement Using Transdermal Optical Imaging Technology