What Is Acoustic Trauma?
Acoustic trauma is an injury to the inner ear that is often caused by exposure to a high decibel noise. This injury can be related to a single very loud noise or by exposure to a lower decibel noise over a long period of time. Some injuries to the head can cause acoustic trauma if the eardrum is ruptured, or if other injuries to the inner ear occur.
The eardrum protects the middle and inner ear. It also transmits signals to the brain by way of small vibrations. Acoustic trauma can damage the way that these vibrations are handled, causing hearing loss. Sound moving into the inner ear can cause what doctors sometimes call a “threshold shift,” which can trigger hearing loss.
Types of Acoustic Trauma
If your doctor believes that your symptoms indicate acoustic trauma, he or she may try to differentiate between trauma that occurred through injury and trauma that occurred through exposure to loud noises. Different degrees of acoustic trauma can also require different treatments.
Who Is at High Risk for Acoustic Trauma?
Those who experience the following types of situations are at a higher risk for acoustic trauma:
- those who work at a job where loud industrial equipment operates for long periods of time
- those who live or work where other high-decibel sounds continue for long periods of time
- individuals who frequently attend music concerts and other events with high-decibel music
- those who use gun ranges
- people who experience gun reports or other extremely loud sounds without proper equipment, such as earplugs
In terms of specific risks, those exposed to over 85 decibels of sound continually are at a higher risk for acoustic trauma. Your doctor may provide an estimate of the decibel range of normal daily sounds, such as an estimate of around 90 decibels for a small engine, in order to help you assess whether the sounds that you encounter put you at a higher risk for acoustic trauma and hearing loss.
Symptoms of Acoustic Trauma
The main symptom of acoustic trauma is hearing loss. Experts point out that, in many cases, patients first begin to experience difficulty hearing high-frequency sounds. Trouble with sounds at lower frequencies may occur later. Doctors may test response to different frequencies of sound to assess the extent of acoustic trauma.
One of the most important symptoms that can signal the onset of acoustic trauma is called tinnitus. Tinnitus is a type of injury to the ear that causes a buzzing or ringing sound. Those with slight to moderate tinnitus will most often be aware of this symptom when they are in a silent environment. While tinnitus can be caused by drug use, changes to blood vessels, or other factors, it is often a precursor to acoustic trauma when it is caused by exposure to loud noises. Tinnitus can be persistent or chronic, where long-term tinnitus is a good reason to suspect acoustic trauma.
Diagnosing Acoustic Trauma
To diagnose acoustic trauma, your doctor will ask you what kind of noises you have been exposed to during different times of your life. Doctors may also use something called audiometry to detect signs of acoustic trauma. This kind of test involves providing sounds of various loudness and different tones in order to more carefully assess what the patient can and can’t hear.
Treating Acoustic Trauma
Technical Hearing Assistance
While hearing loss can be treated, it cannot be cured. Your doctor may recommend technological assistance for your hearing loss condition, such as a hearing aid. New types of hearing aids called cochlear implants may also be available to help you deal with hearing loss from acoustic trauma.
Your doctor will most likely recommend using earplugs and other kinds of hearing protection devices. These items, when applied to a workplace scenario, are part of the PPE (personal protective equipment) that employers should offer to workers.
In some cases, oral steroid medications may be prescribed to help with acoustic trauma. However, if you are experiencing hearing loss, your doctor will stress protection of the ear in order to prevent the problem from getting worse.
Prognosis for Acoustic Trauma
Acoustic trauma and related hearing loss cannot be reversed. Some patients are able to keep the remaining portion of their hearing capacity by protecting their ears from loud noises. In some extreme cases, doctors will recommend learning sign language in order to allow for communications if hearing loss becomes considerable.