Tinnitus and Hearing Loss After a Car Accident

Ringing in the Ears After a Crash

Tinnitus is the perception of sound that does not have an external source, so other people cannot hear it, according to the National Institute on Deafness and Other Communication Disorders (NIDCD). It is commonly described as ringing, though NIDCD notes that some people hear other sounds, such as roaring or buzzing.

Tinnitus is common: surveys estimate that 10 to 25% of adults have it, NIDCD reports, and children can have it too. The causes are unclear, but NIDCD says most people who have tinnitus have some degree of hearing loss.

Hearing loss means being partly or totally unable to hear sound in one or both ears, as MedlinePlus defines it. Ringing or buzzing in the ears sits on the MedlinePlus list of associated symptoms, next to a feeling of pressure in the ear and a feeling of being off balance or dizzy.

Head and Neck Injuries That Affect Hearing

A head or neck injury can damage structures of the ear, the nerve that carries sound signals to the brain, or areas of the brain that process sound, causing tinnitus, according to NIDCD. The same NIDCD page links tinnitus to noise exposure, hearing loss, certain medications, and earwax or ear infections.

Head injury also appears among the risk factors for tinnitus in the MedlinePlus entry on ear noises. A separate MedlinePlus entry on hearing loss lists skull fractures among the ways the ear can be injured and notes that they can damage the structures or nerves of the ear.

A head injury that results in a temporal bone fracture can lead to conductive hearing loss or mixed sensorineural hearing loss, according to the StatPearls review of sensorineural hearing loss. Otic capsule fractures cause severe sensorineural loss through several mechanisms, StatPearls explains, including disruption of the membranous labyrinth, hemorrhage into the cochlea, perilymph fistula, and avulsion or trauma of the cochlear nerve.

Head trauma is on the NIDCD list of conditions that can cause sudden sensorineural hearing loss as well. Even so, only about 10 percent of people diagnosed with sudden hearing loss have an identifiable cause, NIDCD says.

Airbag Noise and Pressure Waves

Airbags instantly inflate with a large volume of gas in a collision, creating a brief (under 100 milliseconds) and intense (150 to 170 dB) pressure wave, according to a 2012 case report in Case Reports in Otolaryngology.

Otologic injuries reported to follow airbag deployment include tympanic membrane perforation, conductive hearing loss, tinnitus, disequilibrium, and sensorineural hearing loss, the authors of that report write. They also say deployment has rarely been reported to cause otologic injuries, and that sensorineural hearing loss from an airbag is rare, with only a few reports in the English literature.

Their patient, a 38-year-old man driving at 40 km per hour when his airbag deployed, developed sensorineural hearing loss and tinnitus in the right ear without vertigo, the report describes, with thresholds of 30 dB at 4 kHz and 25 dB at 8 kHz on that side. The authors concluded that airbag deployment in car accidents is associated with the risk of sensorineural hearing loss.

Noise-induced hearing loss can follow a single exposure to an intense impulse sound, such as an explosion, according to NIDCD. Extremely loud bursts of sound can rupture the eardrum or damage the bones in the middle ear, NIDCD says, and that kind of loss can be immediate and permanent. Loud noise exposure can also cause tinnitus, NIDCD adds, and hearing loss and tinnitus can occur in one or both ears.

Symptoms That Can Accompany Tinnitus

Tinnitus symptoms vary significantly from person to person, NIDCD explains. In the NIDCD description, the phantom sound may be in one ear, both ears, or the head, and it may ring, buzz, roar, whistle, hum, click, hiss, or squeal. NIDCD adds that it can be soft or loud, low or high pitched, and may come and go or stay all the time.

Most tinnitus is subjective, according to NIDCD, meaning only the person who has it can hear the sound. In rare cases the sound pulsates rhythmically, often in time with the heartbeat, and NIDCD says a doctor may then be able to hear it with a stethoscope. That form is called objective tinnitus, and it often has an identifiable cause and is treatable, the institute notes.

Hearing loss itself has its own signs: MedlinePlus lists difficulty following conversations when two or more people are talking, difficulty hearing in noisy areas, trouble telling high-pitched sounds such as “s” or “th” from one another, and hearing voices as mumbled or slurred.

The MedlinePlus entry on ear noises advises contacting a provider when ear noises start after a head injury or come with unexplained dizziness, and the MedlinePlus hearing loss entry does the same for sudden, severe hearing loss. The warning signs below come from those two MedlinePlus pages.

Sudden Hearing Loss Is an Emergency

Sudden sensorineural hearing loss, commonly called sudden deafness, is an unexplained, rapid loss of hearing either all at once or over a few days, according to NIDCD. NIDCD notes that it frequently affects only one ear and says people often discover it on waking, notice it when they try to use the ear on a phone, or hear a loud, alarming pop just before the hearing disappears. Ear fullness, dizziness, and tinnitus can come with it, according to NIDCD.

Some people put off a visit because they think allergies, a sinus infection, or earwax is to blame, NIDCD says, but the symptoms should be considered a medical emergency. About half of people with sudden deafness recover some or all of their hearing spontaneously, usually within one to two weeks of onset, but NIDCD warns that delaying diagnosis and treatment can decrease treatment effectiveness.

The workup starts by ruling out conductive hearing loss from an obstruction such as fluid or earwax, according to NIDCD. When no obvious cause turns up on examination, NIDCD says the doctor should perform pure tone audiometry within a few days of symptom onset. In the NIDCD description, one sign of sudden deafness could be a loss of at least 30 decibels in three connected frequencies within 72 hours, a drop that would make conversational speech sound like a whisper.

Corticosteroids are the most common treatment, especially when the cause is unknown, NIDCD reports, and treatment delayed for more than two to four weeks is less likely to reverse or reduce permanent hearing loss. The StatPearls review of sensorineural hearing loss notes that spontaneous improvement in hearing is most likely to occur during the first two weeks.

Somatosensory Tinnitus and Neck Movement

Moving the head, neck, or eyes, or touching certain parts of the body, may produce tinnitus or temporarily change the quality of the sound, according to NIDCD. NIDCD calls this somatosensory tinnitus.

Twenty percent of people visiting tinnitus clinics have normal hearing, the StatPearls review of tinnitus reports, and some of them have somatosensory tinnitus. In that form, StatPearls explains, stimulation from the cervical region or a temporomandibular joint disorder activates the dorsal cochlear nucleus, which sends impulses to the auditory center. As evidence, StatPearls points to findings that stimulation similar to whiplash or a TMJ disorder has been shown to cause anatomical changes in the dorsal cochlear nucleus.

The joint that connects the lower jaw to the skull is close to the ear, NIDCD notes, and jaw clenching or tooth grinding can damage surrounding tissue, causing or worsening tinnitus. MedlinePlus also names temporomandibular joint disorder among the risk factors for tinnitus. The TMJ and jaw injury page covers that joint in more detail.

Conductive Versus Inner Ear Damage

Conductive hearing loss comes from a mechanical problem in the outer or middle ear, MedlinePlus explains. In the MedlinePlus description, sound may not be reaching the eardrum, the eardrum may not be vibrating in response to sound, or the three tiny bones of the ear may not be conducting sound properly. A hole in the eardrum and damage to those small bones are both on the MedlinePlus list of causes, and MedlinePlus says causes of conductive loss can often be treated.

Sensorineural hearing loss occurs when the tiny hair cells that detect sound in the inner ear are injured, diseased, not working correctly, or have died, and MedlinePlus says this type often cannot be reversed. The StatPearls review of sensorineural hearing loss calls it the most common type and defines it as hearing loss from a pathology of the cochlea, the auditory nerve, or the central nervous system.

The table below sets the two patterns beside tinnitus that occurs with normal hearing, using the MedlinePlus, StatPearls, and NIDCD descriptions cited on this page.

Tinnitus can be a symptom of almost any ear problem, according to the MedlinePlus entry on ear noises, including ear infections, wax in the ear, Meniere disease, and problems with the eustachian tube, and antibiotics, aspirin, or other medicines may also cause ear noises.

Audiometry and Hearing Tests

Formal hearing testing can give a more exact measure of hearing than the simple tests done in the office, MedlinePlus explains. In pure tone testing, MedlinePlus says, tones of a specific frequency and volume reach one ear at a time through earphones, the minimum volume needed to hear each tone is graphed, and a bone oscillator placed against the mastoid bone tests bone conduction.

Speech audiometry tests the ability to detect and repeat spoken words at different volumes, MedlinePlus says. Immittance audiometry, according to MedlinePlus, measures the function of the eardrum and the flow of sound through the middle ear, and tympanometry measures eardrum vibration and middle ear pressure. In detailed audiometry, MedlinePlus counts hearing as normal when tones from 250 to 8,000 Hz can be heard at 25 dB or lower.

In sensorineural loss, both air and bone conduction curves worsen with no air-bone gap, the StatPearls review of sensorineural hearing loss explains, while in conductive loss the air conduction curve shifts downward and the bone conduction curve stays the same. StatPearls calls a complete audiometric evaluation the gold standard for evaluating hearing loss.

The patient is asked to match a tone to the tinnitus and to estimate how loud it sounds, according to the StatPearls review of tinnitus, and the audiologist measures how long a masking tone relieves it. StatPearls notes that the longer the tinnitus is inhibited, the better the prognosis.

Imaging and Specialist Referral

NIDCD recommends seeing a primary care doctor first, who checks for earwax or fluid from an ear infection blocking the ear canal. A referral to an otolaryngologist, an ear, nose, and throat doctor (ENT), may follow, NIDCD says. The ENT asks the patient to describe the sounds and when they started and examines the head, neck, and ears, and an audiologist can measure hearing and evaluate the tinnitus.

X-rays and MRIs are not usually done for tinnitus unless there is an unexplained difference in hearing and balance in the ears, the StatPearls review of tinnitus says. NIDCD adds that the ENT may order MRI, CT, or ultrasound, especially when the tinnitus pulsates, to reveal whether a structural problem or underlying medical condition is responsible.

Audiometry, head CT, head MRI, and blood vessel tests such as duplex Doppler ultrasound and angiography are on the MedlinePlus list of tests that may be done for ear noises. For hearing loss, MedlinePlus reserves CT or MRI of the head for cases where a tumor or fracture is suspected.

After a sudden deafness diagnosis, NIDCD says additional tests may include blood tests, imaging, usually MRI, and balance tests to look for an underlying cause.

Treatment Options for Lasting Tinnitus

There is currently no cure for tinnitus, NIDCD says, but there are ways to reduce symptoms, including sound therapy devices such as hearing aids, behavioral therapies, and medications. When tinnitus has an underlying physiological cause such as earwax or a jaw joint problem, addressing the cause can eliminate or greatly reduce symptoms, NIDCD explains. For many people, though, NIDCD notes that symptoms can persist for months or even years.

NIDCD describes tabletop or smartphone sound generators, wearable sound generators, and combination devices, and it calls hearing aids one of the main treatment options for people with tinnitus who have hearing loss, since they amplify outside sounds while making the tinnitus less noticeable. A hearing aid is always beneficial when tinnitus is associated with hearing loss, the StatPearls review of tinnitus states, though it adds that success is variable.

Cognitive behavioral therapy teaches people to identify negative thoughts that cause distress, and NIDCD says studies have shown it can help improve the well-being of people with tinnitus. Tinnitus retraining therapy, as NIDCD describes it, pairs counseling with continuous low-level sound from a device worn in the ear so the person gets used to the presence of tinnitus.

There are no medications specifically for treating tinnitus, NIDCD says, though a doctor may prescribe antidepressants or anti-anxiety medications to improve mood or sleep. Vitamins, herbal extracts, and dietary supplements advertised as cures have not been proven effective, according to NIDCD. Many medicines are used to relieve tinnitus symptoms, MedlinePlus adds, but no medicine works for everyone.

Recovery Ranges and Long-Term Outlook

Tinnitus may improve or even go away over time, but in some cases it worsens with time, according to NIDCD. Once it lasts three months or longer, NIDCD considers it chronic.

Tinnitus from loud noise may subside over time but can sometimes continue constantly or occasionally throughout a person’s life, NIDCD says. A temporary hearing loss from impulse or continuous loud noise can disappear 16 to 48 hours later, and NIDCD adds that recent research suggests there may be residual long-term damage even when the loss seems to disappear.

For sudden deafness, about half of people recover some or all of their hearing spontaneously, usually within one to two weeks from onset, according to NIDCD. The StatPearls review of sensorineural hearing loss names four factors that help predict the outcome: time since onset, age, vertigo, and degree of hearing loss. StatPearls notes that earlier presentation carries a better prognosis, while vertigo is a poor prognostic indicator.

For sensorineural hearing loss after airbag deployment, the authors of the Case Reports in Otolaryngology report write that steroids are the usual treatment, but that the prognosis is not very good and permanent hearing loss often remains.

Effects on Sleep and Concentration

Tinnitus is only rarely associated with a serious medical problem and is usually not severe enough to interfere with daily life, according to NIDCD. Some people find that it affects their mood and their ability to sleep or concentrate, and in severe cases NIDCD says tinnitus can lead to anxiety or depression.

Patients surveyed about tinnitus reported inability to concentrate, constant awareness, effects on sleep, intrusiveness, and an overall loss of control over their lives, the StatPearls review of sensorineural hearing loss notes. Many patients with sensorineural loss often find tinnitus and dizziness harder to tolerate than the hearing loss itself, and StatPearls adds that patients also reported fear of the tinnitus itself and of living with it long term.

In hyperacusis, ordinary sounds like closing doors, moving chairs, and dropping books become extremely uncomfortable or sometimes unbearable, the StatPearls review of tinnitus explains, and the StatPearls sensorineural hearing loss review reports hyperacusis in 40% of tinnitus sufferers.

Various studies have shown a correlation between uncorrected hearing loss and cognitive decline, the same sensorineural hearing loss review reports. Many patients find hearing loss isolating, according to the same review, and activities they once enjoyed, such as going out to a restaurant or meeting family and friends, become stressful for them, and they withdraw from them.

Records That Track Hearing Changes

Establishing the hearing level before the injury is crucial to direct rehabilitation and to tell whether a hearing loss is new or a worsening of an existing picture, according to the StatPearls review of sensorineural hearing loss. The history StatPearls describes covers age of onset, which side is affected, how fast hearing declined, fluctuating symptoms, and associated tinnitus, ear fullness, imbalance, and vertigo. StatPearls also lists questions about prior ear surgery, noise exposure, head trauma, barotrauma, and ototoxic exposure to aminoglycosides.

After sudden sensorineural loss, StatPearls says a repeat audiogram should be done to assess improvement, and hearing counts as fully recovered when the follow-up pure tone average has improved to within 10 dB of the level before the loss.

Tinnitus can be a side effect of certain medications, especially at high doses, NIDCD notes, naming NSAIDs, certain antibiotics, anti-cancer drugs, anti-malaria medications, and antidepressants. MedlinePlus advises reviewing all current medicines with a provider, including over-the-counter medicines, vitamins, and supplements, to see whether one may be causing the problem.