The loud blasts from improvised explosive devices, or IEDs, in war zones is causing an uptick in hearing loss among soldiers and has gotten the U.S. Department of Defense concerned. Twenty-eight percent of all military personnel experience some degree of hearing loss post-deployment.
But new research out of Stanford shows that much of what was believed to be permanent hearing loss from loud blasts such as these may actually be reversible.
In a press release I wrote about this DOD-sponsored study, I describe the hopeful results:
Using a mouse model, the study found that loud blasts actually cause hair-cell and nerve-cell damage, rather than structural damage, to the cochlea, which is the auditory portion of the inner ear. This could be good news for the millions of soldiers and civilians who, after surviving these often devastating bombs, suffer long-term hearing damage.
The senior author of the study, John Oghalai, MD, associate professor of otolaryngology at Stanford, said that not all of the damage occurs immediately after the explosion. More damage occurs as the body’s immune system tries to heal the injury. The creation of scar tissue to help heal the injury is a particular problem in the ear because the organ needs to vibrate to allow the hearing mechanism to work:
With one loud blast, you lose a huge number of (hearing) 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.
Oghalai said that the surprising results have determined the course of new research looking into ways of reversing or blocking further hearing loss. He told me:
There is going to be a window where we could stop whatever the body’s inflammatory response would be right after the blast. We might be able to stop the damage.
Previously: Hearing loss patient discusses why Stanford research gives her hope for an eventual cure, “What’s that?” Stanford researchers identify cells important to hearing loss, Regenerating sensory hair cells to restore hearing to noise-damaged ears, Stanford researcher comments on the use of human embryonic stem cells to restore hearing and Growing new
inner-ear cells: a step toward a cure for deafness
Photo by adamhenning