Hearing acoustic trauma

Hearing loss caused by a sudden loud noise in one ear, or by a sudden blow to the head. In most cases, hearing loss is temporary, although there may be some permanent loss. Welding sparks (to the eardrum), blows to the head, and blast noise are examples of events capable of producing acoustic trauma. 

Slowly progressive inner-ear hearing loss resulting from exposure to continuous noise over a long period of time, as contrasted with acoustic trauma or physical injury to the ear. NIHL is permanent, painless, and progressive, but is preventable if hearing protection is worn 100 percent of the time during noise exposure. See also Acoustic Trauma. 

Acoustic Trauma Loud noise from explosions, artillery guns or cannons or from similar sources of pressure waves may mpture the eardmm or damage the stmcture of the middle or inner ear. Such conductive damage has the name acoustic trauma. In some cases there is temporary damage. The injured tissue may heal, restoring hearing to full or nearfull sensitivity. In other cases, the physical injury will produce permanent hearing loss. 

There are three principal categories of NHL (1) temporary threshold shift (TTS), (2) permanent threshold shift (PTS), and (3) acoustic trauma. TTS occurs when exposure to sound damages the organ of Corti and its receptor cells. However, if the exposure is of relatively short duration, hearing sensitivity returns to preexposure levels after a recovery period (Brauer 1994). PTS, on the other... 

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