Smartphone App Evaluated to Detect Physical Symptoms of Stroke

August 8, 2023—Investigators from the UCLA David Geffen School of Medicine in Los Angeles, California, and multiple medical institutions in Bulgaria conducted a study of a smartphone app created with the power of machine learning that reliably recognizes patients’ physical signs of stroke.

Data from 240 patients experiencing a stroke at four metropolitan stroke centers were collected. Investigators used smartphones to record videos of patients and test their arm strength in order to detect facial asymmetry, arm weakness, and speech changes within 72 hours of the start of these stroke symptoms.

The study, “Smartphone-Enabled Machine Learning Algorithms for Autonomous Stroke Detection,” was presented at SNIS 2023, the Society of NeuroInterventional Surgery’s 20th annual meeting held July 31 to August 4 in San Diego, California.

According to the SNIS press release, the investigators evaluated facial asymmetry using machine learning to analyze 68 facial landmark points. To test arm weakness, they used data from the smartphones’ standard internal three-dimensional accelerometer, gyroscope, and magnetometer. Speech changes were determined using mel-frequency cepstral coefficients, a sound recognition method that translates sound waves into images, to compare normal and slurred speech patterns.

Investigators then tested the app using neurologists’ reports and brainscan data, finding that the app was sensitive and specific enough to diagnose stroke accurately in approximately all cases.

“It’s exciting to think how this app and the emerging technology of machine learning will help more patients identify stroke symptoms upon onset,” commented Radoslav Raychev, MD, in the SNIS press release.

Dr. Raychev, who is a vascular and interventional neurologist from the Geffen School of Medicine, continued “Quickly and accurately assessing symptoms is imperative to ensure that people with stroke survive and regain independence. We hope the deployment of this app changes lives and the field of stroke care.”