A recent research published in the American Heart Association Journal Circulation: Cardiovascular Imaging, blood pressure could one day be measured using a smartphone. A team of researchers has concluded that blood pressure can be measured using a video selfie in the future.
The technology is fairly simple, a group of sensors takes imaging from the outer layer of the skin and the repeated photos or a video is used to analyze the blood flow patterns. This data obtained by the video can be compared against transdermal optical imaging models to predict blood pressure with a fair amount of accuracy.
High blood pressure (hypertension) has affected millions across the globe and is responsible for clots inside the arteries. Unchecked high blood pressure can lead to hardening and blockage of the arteries. This can have grave consequences as it may lead to dementia or even stroke.
“High blood pressure is a major contributor to cardiovascular disease—a leading cause of death and disability. To manage and prevent it, regular monitoring of one’s blood pressure is essential,” said study lead author Kang Lee. Mr. Lee serves as a professor of psychology at the University of Toronto. “Cuff-based blood pressure measuring devices, while highly accurate, are inconvenient and uncomfortable. Users tend not to follow American Heart Association guidelines and device manufacturers’ suggestion to take multiple measurements each time,” he added.
Mr. Lee who is also a research head in developmental neuroscience at the University of Toronto along with his team ran their tests on more than 1300 adults from different geographical backgrounds. A specialized software was installed on an iPhone which took 2-minute videos of the people and analyzed it using transdermal optical imaging software.
Blood flow patterns obtained from the smartphone were compared to patterns obtained from traditional blood pressure measurement devices. These patterns contained data regarding the systole, diastole and the pulse during the 2 minutes of measurement.
The data was used by the team to ‘teach’ the computers and software to accurately determine the systolic, diastolic and pulse readings. The system was configured further to obtain their readings from a facial video. The results from the system were promising as it predicted the blood pressure and pulse measurements with around 95% accuracy.
Kang Lee has high hopes for the transdermal imaging software as the accuracy with which it predicts the blood pressure is within the international standards for such blood pressure measuring devices.
The technology requires specific conditions to work effectively. A well-controlled environment with fixed lighting is a necessity for the required video to measure the blood pressure more accurately. In addition to it, varying skin tones from person to person may be troublesome in producing accurate results, as there is a lack of samples for extremely dark or fair skin tones. Struggles are being made to shorten the needed video length from 2 minutes to 30 seconds in order to make the software more convenient for its users.
People in the study all had normal blood pressure. “If future studies confirm our results and show this method can be used to measure blood pressures that are clinically high or low, we will have the option of a contactless and non-invasive method to monitor blood pressures conveniently—perhaps anytime and anywhere—for health management purposes,” Lee said.
“This study shows that facial video can contain some information about systolic blood pressure,” said Ramakrishna Mukkamala. Ramakarishna is the Circulation Imaging editorial author and professor at Michigan State University. His is a faculty member of the Department of Electrical and Computer Engineering. “If future studies could confirm this exciting result in hypertensive patients and with video camera measurements made during daily life, then obtaining blood pressure information with a click of a camera may become a reality.”
These findings from the study can prove to be a much-needed breakthrough in the control of high blood pressure. This can be used in conjunction with other health apps to provide the general public with more active and safer living.