Analysis of smartphone video motion revealed narrowing of the neck arteries, which could lead to stroke

Highlights of the study:

  • In a small study in Taiwan, motion analysis of smartphone video accurately identified narrowing of the carotid arteries, a risk factor for stroke in adults.

  • Smartphone video motion analysis technology may be an early screening tool to detect narrowed arteries in the neck, which may improve patient outcomes.

Embargo until 4pm CT/5am ET 50. 17, 2022

(NewMediaWire) – August 17, 2022 – DALLAS Motion analysis of smartphone video pinpoints narrowed arteries in the neck as a risk factor for stroke, according to a new study released today. Journal of the American Heart AssociationAn open access, peer-reviewed journal of the American Heart Association.

Fatty deposits (plaque) can build up in the arteries and cause them to narrow (stenosis). Narrowed arteries in the carotid artery (neck) can cause an ischemic stroke, which occurs when a clot forms in a vessel that supplies blood to the brain. Almost 87% of all strokes are ischemic strokes.

“Each year, 2% to 5% of strokes occur in people without symptoms, so better and earlier detection of stroke risk is needed,” said lead study author Hsien-Li Kao, MD, an interventional cardiologist at National Taiwan University Hospital in Taiwan. Taipei, Taiwan.

“It was an exciting eureka moment for us,” Cao said. “Current diagnostic methods such as ultrasound, CT, and MRI require screening with specialized medical imaging equipment and staff. Smartphone video analysis is noninvasive and easy to perform, so it may allow for increased screening. More research and development. If necessary, recording and motion analysis can be executed remotely, or a downloadable app can even be executed.”

The arteries in the neck are located beneath the surface of the skin, and changes in the speed and pattern of blood flow through them are reflected in the movement of the overlying skin, Cao explained. However, these differences are not visible to the naked eye.

This study, conducted between 2016 and 2019, used motion magnification and pixel analysis to detect minute changes in skin surface pulse characteristics captured in smartphone video recordings.

The study included a group of 202 Taiwanese adults (mean age 68 years; approximately 79% male) receiving care at a Taiwanese hospital. 54% of the participants had significant carotid artery stenosis, meaning that they had at least 50% obstruction previously detected by ultrasound, while 46% did not have significant stenosis. The recordings involved participants lying supine with their heads tilted back in a specially designed box that minimized external motion. Apple iPhone 6, 64GB, boxed to capture 30-second video recording of a person’s neck. As Cao explained, the older generation phone was used because the researchers believed it was more common for the average user.

The researchers found that the video motion analysis algorithm had an 87% accuracy in detecting stenosis in the group with carotid artery stenosis. All study participants also underwent standard Doppler ultrasound tests to measure and confirm arterial stiffness and values ​​obtained from video motion analysis.

“More research is needed to determine if video recorded on smartphones is a promising method to help speed up and increase stroke screening,” Cao said. “Carotid artery stenosis is silent until a stroke occurs. With this method, doctors can take video of the patient’s neck with a smartphone, upload the videos for analysis, and receive a report within five minutes. Early detection of carotid artery stenosis can improve patient outcomes.”

The study had several limitations, including the small number of study participants, all of whom were at high risk for a cardiovascular event. In addition, neck length and neck angle were not analyzed, which may affect the results of the video analysis. According to Kao, skin color does not preclude use in the general population because a standard lighting method was used for this evaluation.

Co-authors Cheng-Huan Tsai, MD; Ching-Chan Huang, MD; Hao-Ming Xiao, MD; Min-Ya Hung, MS; Guan-Jie Su, MS; Lee-Han Lin, MS; Ying-Xian Chen, MD; Mao-Xin Lin, Ph.D.; Chih-Fang Yeh, MD; and Chi-Shen Hung, Ph.D. Authors’ statements appear in the manuscript.

The research was funded by Taiwan’s Ministry of Science and Technology.

Research published in the American Heart Association’s scientific journals is peer-reviewed. Statements and conclusions in each manuscript are solely those of the study authors and do not necessarily reflect the policy or position of the Association. The Association makes no representations or warranties as to their accuracy or reliability. The Association receives funding primarily from individuals; foundations and corporations (including pharmaceuticals, device manufacturers, and other companies) also make charitable contributions and fund specific programs and activities of the Association. The association has a strict policy to prevent these relationships from influencing the content of science. Revenues from pharmaceutical and biotech companies, device manufacturers and health insurance companies and general financial information for the Association are available here.

Additional Resources:

About the American Heart Association

The American Heart Association is a relentless force for the world to live longer, healthier lives. We are dedicated to ensuring equitable health in all communities. Through partnerships with many organizations and millions of volunteers, we fund innovative research, protect public health, and share life-saving resources. The Dallas-based organization has been a leading source of health information for nearly a century. Join us at, Facebook, twitter or by calling 1-800-AHA-USA1.


For media inquiries and AHA/ASA expert opinion: 214-706-1173

Bridget McNeil: 214-706-1135;

For public inquiries: 1-800-AHA-USA1 (242-8721) and

Leave a Comment

Your email address will not be published.