Measurement of hemoglobin within blood helps to diagnose and manage a number of conditions, but this requires either blood draws or expensive pulse oximeters. At the University of Washington a team of researchers wanted to see whether a common smartphone (Nexus 5) can be used to perform the measurement at a high enough accuracy to be useful for medical practice.
They developed an app called HemaApp that uses the phone’s built-in light and camera to detect the color intensity of blood passing through a finger. The user simply places a finger over the camera lens, making a solid contact, and runs the app to do its thing. The app turns on the nearby LED light, which shines light through the finger, and uses the camera to detect specific features that point to the amount of hemoglobin.
While the built-in light is not too bad, the team also tested the app while using a nearby incandescent bulb in addition to the camera light, as well as with the help of a small accessory light attached to the phone. The amazing thing is that in their small study on 31 patients, the HemaApp with the attached light accessory was as accurate (82%) as Masimo’s Pronto (81%) in estimating hemoglobin count. The app without any accessories, and relying only on its own light, had an accuracy of 69%, which is pretty impressive as well.
Here’s a University of Washington video presenting the app:
Link: HemaApp info page…