In the developing world, anemia is a staggeringly common health problem that often goes undiagnosed. As it happens in hospitals, children and adults with leukemia and other disorders require frequent blood draws to determine if they need blood transfusions.
Doctors are interested in measuring hemoglobin a protein found in red blood cells. To obtain this basic measurement, blood has to be drawn with a needle or intravenous line, or doctors need to use a specialized machine to measure hemoglobin non-invasively.
Today, electrical engineers and computer scientists from the University of Washington www.washington.edu with funding from the Washington Research Foundation have developed HemaApp which uses a smartphone camera to estimate hemoglobin concentrations and is able to screen for anemia.
“In developing countries, community health workers have to carry so much specialized equipment to monitor different conditions”, reports Edward Wang, UW Electrical Engineering doctoral student. “We are trying to make these screening tools or devices work on one ubiquitous platform which we want to be the smartphone.”
The HemaApp bombards a patient’s finger with different wavelengths of light and infrared energy to create a series of videos. By analyzing how colors are absorbed and reflected across those wavelengths, concentrations of hemoglobin can be detected along with other blood components like plasma.
The mobile app is not intended to replace blood tests, but it has been found that in a test with patients ranging in age from 6 to 77, the HemaApp can be an effective initial screening tool to determine whether further blood testing is warranted.
In an initial trial of 31 patients, and with only one smartphone modification, HemaApp performed as well as the Masimo Pronto, the more expensive FDA approved medical device that non-invasively measures hemoglobin by clipping a sensor on to a person’s finger.
When used to screen for anemia, HemaApp correctly identified cases of low hemoglobin levels 79 percent of the time using just the phone camera, and 86 percent of the time when aided with some light sources.
The next research step includes doing more national and international testing of the device. It is important for researchers to collect more data to improve accuracy rates when using smartphones to try to detect abnormal hemoglobin properties. In the future, the App could possibly help screen for sickle cell disease and other blood disorders.
For more information, contact the UbiComp research team at hemaapp@cs.washington.edu.