The device uses a non-invasive imaging system called optical coherence tomography (OCT) to collect high-resolution, three-dimensional tissue images from beams of light sent into the ear canal. The system can scan through the eardrum to any biofilm behind it. The researchers, who liken the process to ultrasound imaging that uses light instead of sonic waves, described their work last week in the online Early Edition of the journal .

The light scatters and reflects from the tympanic membrane—which separates the external ear from the middle ear—as well as any biofilm that might be behind the membrane. The researchers measure this reflection to determine whether a biofilm is present as well as its thickness and position against the eardrum.

University of Illinois researchers tested a prototype of a new device that can see biofilms behind the eardrum to better diagnose and treat chronic ear infections.

The research team, led by University of Illinois electrical and computer engineering professor Stephen Boppart, tested their ear OCT device at Carle Foundation Hospital in Urbana, Ill. There they scanned patients with diagnosed chronic ear infections, as well as patients with normal ears. The device identified biofilms in all patients with chronic infections, while none of the normal ears showed evidence of biofilms, according to the researchers.

A closer study of ear infections, the most common conditions that pediatricians treat, could lead to a better understanding of the relationship between biofilms and hearing loss. Boppart and his team also plan to adapt their OCT technique to other areas of medicine with the hope that such imaging technology can be useful in diagnosing health problems originating in the eyes, mouth, nose or skin.