The device would need a power source, and researchers have found that it’s possible to draw a small amount of electricity from a source in the inner ear, the endocochlear potential. In a proof-of-principle study using a chip that can fit on the tip of your index finger, researchers powered a radio transmitter entirely with power from a guinea pig’s inner ear, although the chip was located outside the body and connected with electrodes. This was done without any damage to hearing. “This is the first demonstration that you can use an electrochemical gradient from the body to power an electronic device,” Dr. Stankovic said.
Explore This IssueDecember 2015
She emphasized that this involves only nanowatts of power, and cochlear implants use tens of milliwatts. But the location of the inner ear, which is millimeters from the temporal bone and the facial nerve, could be an important advantage, she said. “We envision that down the line this energy from the inner ear may be used to power various sensors in the inner ear and its vicinity.”
New Treatments for Vestibular Schwannomas
Through a series of discoveries beginning with an examination of all the genes that have ever been reported to be differentially regulated in vestibular schwannomas, Dr. Stankovic’s laboratory could be getting closer to addressing an unmet medical need to develop well-tolerated pharmacologic therapies for these tumors, she said. The genes have been pointing researchers in the direction of inflammation, and the researchers have submitted a grant proposal that suggests research on whether aspirin has a role in their treatment.
Down another avenue, the researchers, noting that tumor compression itself can’t be the cause for hearing loss because tumor size does not correlate with hearing loss, have turned to tumor secretions instead. They now believe that tumor necrosis factor (TNF)-alpha could be a molecule that is toxic to the inner ear and is being secreted by the tumors. “Is it possible that we could use TNF-alpha inhibitors such as the ones that are already in clinical practice … to try to prevent hearing loss in these patients?” Dr. Stankovic asked.
A Possible Role for Bisphosphonates
When researchers performed a mass spectrometry analysis of the human perilymph to study the fluids of the inner ear, doubling what is known about the protein content of the perilymph, they were intrigued by the large amount of osteoprotegerin, a protector of bone remodeling. They now believe that the bisphosphonate zoledronate, which can reverse the effects of osteoprotegerin deficiency, could have a neuroregenerative role in the inner ear, and have received a grant from the Department of Defense to study this possibility.