A recent study done by researchers at Standford University School of Medicine may give hope to veterans that have experienced hearing loss from roadside bombs or other explosions. The study used a mouse model, and shows that the loud blasts actually cause hair-cell and nerve-cell damage, rather than structural damage, to the part of the inner ear responsible for hearing.
This is good news for veterans suffering from hearing loss, because experts previously believed that the cochlea, the delicate structure of the inner ear, was shredded or ripped as the result of loud blasts. Such damage would be irreversible. For the 60 percent or more of soldiers wounded in action that have some level of hearing loss, the new information could mean new treatment options that could be done immediately following a blast to prevent permanent damage.
“When we looked inside the cochlea, we saw the hair-cell loss and auditory-nerve-cell loss,” John Oghalai, MD, associate professor of otolaryngology and senior author of the study, said.
“With one loud blast, you lose a huge number of these cells. What’s nice is that the hair cells and nerve cells are not immediately gone. The theory now is that if the ear could be treated with certain medications right after the blast, that might limit the damage.”
The body responds to the damage by creating scar tissue to help heal the injury. The scar tissue, in turn, prevents the vibrations needed to allow the hearing mechanisms to work.
“There is going to be a window where we could stop whatever the body’s inflammatory response would be right after the blast,” Oghalai said. “We might be able to stop the damage. This will determine future research.”
Ramie Tritt, M.D., President, Atlanta ENT