Infrared instrument lets doctors see through eardrums to spot infections
In the US, an estimated two million children are incorrectly diagnosed with ear infections every year, and unnecessarily prescribed antibiotics. A new device that switches out conventional visible light observations for shortwave infrared could help, letting doctors peer deeper into the ear than normal. It's designed to be similar to existing otoscopes, meaning doctors won't need dedicated training to use it, and should allow for much more accurate diagnoses.
A key symptom of a middle-ear infection is a build-up of fluid behind the eardrum, but conventional otoscopes – those devices that doctors use to peer into your ear – use visible light to illuminate the inside of the ear, and can't see past the eardrum.
"If there's no fluid, there's no chance of an infection," said study author Jessica Carr. "One of the limitations of the existing technology is that you can't see through the eardrum, so you can't easily see the fluid. But the eardrum basically becomes transparent to our device."
Unlike conventional devices, the MIT-developed alternative makes use of shortwave infrared light, which can easily penetrate the tissue. If there's fluid present behind the eardrum, it shows up as a dark mass when viewed through the device, making it a lot easier for doctors to make an assessment as to whether the patient requires antibiotics.
According to the researchers, there are other systems under development that provide doctors with similar data as the new MIT instrument, but they require the user to have specialized training to use. The team's device is designed to be a similar as possible to an otoscope, which doctors already use regularly.
The team believes that its device could significantly cut down the number of false positive diagnoses made by doctors. On their own, those errors may seem harmless enough, but such unnecessary prescriptions are a big factor in a much larger issue – the rise of antibiotic-resistant bacteria.
As to the new device, the researchers have already successfully tested it on 10 adult subjects, and the team is now looking to trial it on younger patients to confirm its accuracy as a diagnostic instrument.
A paper concerning the new instrument is published online in the journal PNAS.