Ear infections are the most common reason that parents bring their children to a pediatrician, according to the National Institutes of Health.


The app teaches parents how to use it. (Dennis Wise/UW)

Ear infections occur when fluid builds up in the middle ear behind the eardrum and becomes infected, making it painful and hard for children to hear. The smart-phone app can detect fluid behind the eardrum by simply using a piece of paper and a smartphone’s microphone and speaker. The smartphone makes a series of soft audible chirps into the ear through a small paper funnel and depending on the way the chirps are reflected back to the phone, the app determines the likelihood of fluid present with a probability of detection of 85%. This is on par with current methods used by specialists to detect fluid in the middle ear that involve specialized tools using acoustics or a puff of air. The funnel rests on the outer ear and guides sound waves in and out of the ear canal. When the phone plays a continuous 150-millisecond sound — which sounds like a bird chirping — through the funnel, the sound waves bounce off the eardrum, travel back through the funnel, and are picked up by the smartphone’s microphone along with the original chirps. Different sounds are made depending on how much liquid is in the ear.


University of Washington, Seattle


The researchers plan on commercializing this technology and making the app available to the public.


Dr. Randall Bly, an assistant professor of otolaryngology-head and neck surgery at the UW School of Medicine, uses the app to check his daughter’s ear. (Dennis Wise/UW)

Once diagnosed, ear infections can be easily treated with observation or antibiotics, and persistent fluid can be monitored or drained by a doctor to relieve symptoms of pain or hearing loss. Fluid behind the eardrum is so common in children that there is a direct need for an accessible and accurate screening tool that can be used at home or in clinical settings.