A smartphone application utilizing a camera to assess blood flow in the wrist artery in patients undergoing coronary angiography was able to outperform traditional physical examination, according to a study published April 3 in Canadian Medical Association Journal.
Physicians are currently limited to the modified Allen test to measure blood flow of the wrist. In this study, researchers evaluated the feasibility and accuracy of using the Instant Heart Rate application on an iPhone in assessing wrist blood flow in patients.
"Because of the widespread availability of smartphones, they are being used increasingly as point-of-care diagnostics in clinical settings with minimal or no cost," said Benjamin Hibbert, MD, PhD, of the University of Ottawa Heart Institute. "For example, built-in cameras with dedicated software or photodiode sensors using infrared light-emitting diodes have the potential to render smartphones into functional plethysmographs [instruments that measure changes in blood flow]."
Some 438 patients were evenly split into two groups—one being assessed with the app and others by traditional physical examination. In the participants being assessed by the app, researchers measured photoplethysmography readings by placing the smartphone camera lens on the patient’s index finger. All participants were additionally given a doppler ultrasound of the wrist arteries to test diagnostic accuracy.
Results showed the smartphone app had a diagnostic accuracy of 94 percent, topping the 84 percent accuracy measured using the Allen test.
"However, while they aren't designed as medical devices—when smartphones and apps begin to be used clinically—it is important that they are evaluated in the same rigorous manner by which we assess all therapies and diagnostic tests," said lead author Pietro Di Santo. "When we designed the iRadialstudy we wanted to hold the technology to the highest scientific standards to make sure the data supporting its use was as robust as possible."
Cara joined TriMed Media in 2016 and is currently a Senior Writer for Clinical Innovation & Technology. Originating from Detroit, Michigan, she holds a Bachelors in Health Communications from Grand Valley State University.