NEW YORK — Indian American researchers from Rice University have created a touch-free system that uses a video camera to monitor the vital signs of patients just by looking at their faces.
The team of graduate student Mayank Kumar and professors Ashok Veeraraghavan and Ashutosh Sabharwal created the system that will let doctors diagnose patients from a distance with special attention paid to those in low-resource settings.
The technique, called DistancePPG, can measure a patient's pulse and breathing just by analyzing the changes in one's skin color over time.
Where other camera-based systems have been challenged by low-light conditions, dark skin tones and movement, DistancePPG relies on algorithms that correct for those variables.
"DistancePPG will be particularly helpful to monitor premature infants for whom blood pressure cuffs or wired probes can pose a threat," said Mayank Kumar, the project's lead graduate researcher.
The wires monitor babies' pulses and heart rate.
"The wires are not a problem. The problem is that the babies would roll or their mothers need to take care of them and the wires are taken off and put back on," Kumar said.
That could potentially damage the infants' delicate skin. The existing techniques worked fine in bright rooms but there were challenges.
"Our key finding was that the strength of the skin-color change signal is different in different regions of the face, so we developed a weighted-averaging algorithm," Kumar explained.
It improved the accuracy of derived vital signs, rapidly expanding the scope, viability, reach and utility of camera-based vital-sign monitoring.
According to the researchers, they expect the software to find its way to mobile phones, tablets and computers so people can reliably measure their own vital signs whenever and wherever they choose.
The research appeared in the journal Biomedical Optics Express.