Noise Induced Hearing Loss (NIHL) from blasts may be reversible
Damage to auditory hair cells and nerve cells from exposure to loud noise such as blasts from bombs and firearms may be reversible according to a study by researchers at Stanford University of Medicine. They have found that blasts can cause damage to hair cells and nerve cells but not structural damage to the cochlear which means that medication may be developed in the future to reduce this damage.
Among soldiers and veterans with service connected disabilities, tinnitus is the most prevalent, followed by hearing loss but the study will benefit anyone who is exposed to loud blasts such as jet engines, car airbags or gunfire.
They say, the ears are extremely fragile instruments. Sound waves enter the ear, causing the eardrums to vibrate. These vibrations get sent to the cochlea in the inner ear, where fluid carries them to rows of hair cells, which in turn stimulate auditory nerve fibers. These impulses are then sent to the brain via the auditory nerve, where they get interpreted as sounds. And 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.
Much of the resulting hearing loss after such blast damage to the ear is actually caused by the body's immune response to the injured cells, Oghalai said. 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. Scar tissue damages that ability.
Read the press release: http://med.stanford.edu/ism/2013/july/blast.html