Tinnitus – Causes, Symptoms, Diagnosis, Treatment

Tinnitus is defined as a sound a person hears that is generated by the body, rather than by outside source. Most tinnitus is subjective. This means the examiner cannot hear it, and there are no tools to measure or hear that sound. Objective tinnitus can arise from an aneurysm. This can be objectified and heard by the examiner. Other objective tinnitus investigation includes temporomandibular joint disease (TMJD) and tensor tympani muscle spasm.[rx][rx][rx][rx]

The word “tinnitus” comes from the Latin word for “ringing.” But the sounds that people with tinnitus hear also include whistling, buzzing, humming, hissing, clicking, or knocking. They may be heard in one or both ears. Some people say it feels like the sound is coming from inside their head, whereas others say it sounds like it is coming from outside. Tinnitus may be constant or it may come and go. It is sometimes very quiet and then really loud again.

Types of Tinnitus

Based on the outcomes of the doctor’s examination, he or she will determine which type of tinnitus you have. Doctors distinguish between the following types of tinnitus:

• Subjective and objective tinnitus – Subjective tinnitus can only be heard or perceived by the person who has it. Possible causes include problems with the auditory (hearing) system or the nerves that belong to it. In objective tinnitus, which is very rare, the doctor can hear the sounds too or detect the nerve signals causing the sounds. This is the case with tinnitus that is caused by blood-vessel-related problems, for instance. Here the doctor can hear a pulsing noise in the carotid artery in the neck with the help of a stethoscope.
• Primary and secondary tinnitus – If no clear cause can be found, it is referred to as primary tinnitus or idiopathic tinnitus. If there is an identifiable cause, it is known as secondary tinnitus. Possible causes include a perforated eardrum or a vascular (blood vessel) disease.
• Acute and chronic tinnitus – If the sounds last longer than three months, it is considered to be chronic tinnitus.
• Various levels of severity – Tinnitus can be mild and hardly affect your everyday life, or only occur from time to time but then be distressing when it does. Sounds that are constantly and clearly heard are more serious: They can have a big impact on your daily life and work, for instance, because it is hard to sleep and concentrate properly.

Tinnitus differs for each patient. In one person, it could be humming in the ear and for another person, it could be a ringing sound. The volume varies for each person, which is why medical practitioners divide tinnitus into four degrees of severity.

• Degree 1 – Tinnitus can be compensated for and does not disturb the impacted person.
• Degree 2 – Tinnitus is largely compensated for, but still occurs when quiet and becomes disruptive when under the stress of other taxing situations.
• Degree 3 – The tinnitus symptoms considerably impact private and professional life. It causes irritability as well as emotional and physical problems. The patients suffer from disruptions to sleep and concentration, muscle tension, headaches as well as feelings of helplessness.
• Degree 4 – The ongoing impacts of tinnitus are so great that they have an extremely negative impact on the quality of life. Patients can no longer maintain their jobs, withdraw from their social lives, and suffer from immense psychological issues, such as anxiety and depression.

Causes of Tinnitus

There are many causes of tinnitus:

• The most common cause of subjective tinnitus is noise trauma. For example, an employee who works in a noisy industry loses hearing at the 4000 Hz tone. Now the employee hears a sound which is similar to the 4000 tones.
• Metabolic diseases: Heart, hypertension, diabetes are associated with an onset of tinnitus. Various drugs are ototoxic to some individuals or at sufficient doses. For example, high doses of aspirin cause tinnitus, and the issue resolves when aspirin is stopped.
• Ear diseases cause tinnitus including Meniere disease or lesions affecting the eighth cranial nerve.
• Other possible causes of tinnitus include the following:
  • Blocked ear (auditory) canal due to a build-up of ear wax
  • Chronic middle ear infection
  • A ruptured (perforated) eardrum
  • Otosclerosis: a bone disease in the middle ear and inner ear that can lead to hearing loss
  • Ménière’s disease: a disease of the inner ear, causing symptoms such as tinnitus, vertigo and hearing loss
  • Problems affecting the muscles or joint of the jaw

Twenty percent of persons visiting tinnitus clinics have normal hearing. Some have somatosensory tinnitus. Here, stimulation from cervical or TMJD has activated the dorsal cochlear nucleus and sends impulses to the auditory center. Evidence for this is that stimulation similar to whiplash or TMJD has been shown to cause anatomical changes in the dorsal cochlear nucleus.[rx][rx][rx]

Common causes of tinnitus

In many people, tinnitus is caused by one of these conditions:

• Age-related hearing loss – For many people, hearing worsens with age, usually starting around age 60. Hearing loss can cause tinnitus. The medical term for this type of hearing loss is presbycusis.
• Exposure to loud noise – Loud noises, such as those from heavy equipment, chain saws and firearms, are common sources of noise-related hearing loss. Portable music devices, such as MP3 players or iPods, also can cause noise-related hearing loss if played loudly for long periods. Tinnitus caused by short-term exposure, such as attending a loud concert, usually goes away; both short- and long-term exposure to loud sound can cause permanent damage.
• Earwax blockage – Earwax protects your ear canal by trapping dirt and slowing the growth of bacteria. When too much earwax accumulates, it becomes too hard to wash away naturally, causing hearing loss or irritation of the eardrum, which can lead to tinnitus.
• Ear bone changes – Stiffening of the bones in your middle ear (otosclerosis) may affect your hearing and cause tinnitus. This condition, caused by abnormal bone growth, tends to run in families.

Other causes of tinnitus

Some causes of tinnitus are less common, including:

• Meniere’s disease – Tinnitus can be an early indicator of Meniere’s disease, an inner ear disorder that may be caused by abnormal inner ear fluid pressure.
• TMJ disorders – Problems with the temporomandibular joint, the joint on each side of your head in front of your ears, where your lower jawbone meets your skull, can cause tinnitus.
• Head injuries or neck injuries – Head or neck trauma can affect the inner ear, hearing nerves or brain function linked to hearing. Such injuries generally cause tinnitus in only one ear.
• Acoustic neuroma – This noncancerous (benign) tumor develops on the cranial nerve that runs from your brain to your inner ear and controls balance and hearing. Also called vestibular schwannoma, this condition generally causes tinnitus in only one ear.
• Eustachian tube dysfunction – In this condition, the tube in your ear connecting the middle ear to your upper throat remains expanded all the time, which can make your ear feel full. Loss of a significant amount of weight, pregnancy and radiation therapy can sometimes cause this type of dysfunction.
• Muscle spasms in the inner ear – Muscles in the inner ear can tense up (spasm), which can result in tinnitus, hearing loss and a feeling of fullness in the ear. This sometimes happens for no explainable reason, but can also be caused by neurologic diseases, including multiple sclerosis.

Blood vessel disorders linked to tinnitus

In rare cases, tinnitus is caused by a blood vessel disorder. This type of tinnitus is called pulsatile tinnitus. Causes include:

• Atherosclerosis – With age and buildup of cholesterol and other deposits, major blood vessels close to your middle and inner ear lose some of their elasticity — the ability to flex or expand slightly with each heartbeat. That causes blood flow to become more forceful, making it easier for your ear to detect the beats. You can generally hear this type of tinnitus in both ears.
• Head and neck tumors – A tumor that presses on blood vessels in your head or neck (vascular neoplasm) can cause tinnitus and other symptoms.
• High blood pressure – Hypertension and factors that increase blood pressure, such as stress, alcohol and caffeine, can make tinnitus more noticeable.
• Turbulent blood flow – Narrowing or kinking in a neck artery (carotid artery) or vein in your neck (jugular vein) can cause turbulent, irregular blood flow, leading to tinnitus.
• Malformation of capillaries – A condition called arteriovenous malformation (AVM), abnormal connections between arteries and veins, can result in tinnitus. This type of tinnitus generally occurs in only one ear.

Medications that can cause tinnitus

A number of medications may cause or worsen tinnitus. Generally, the higher the dose of these medications, the worse tinnitus becomes. Often the unwanted noise disappears when you stop using these drugs. Medications known to cause or worsen tinnitus include:

• Antibiotics – including polymyxin B, erythromycin, vancomycin (Vancocin HCL, Firvanq) and neomycin
• Cancer medications – including methotrexate (Trexall) and cisplatin
• Water pills (diuretics) – such as bumetanide (Bumex), ethacrynic acid (Edecrin) or furosemide (Lasix)
• Quinine medications used for malaria or other health conditions
• Aspirin and other nonsteroidal anti-inflammatory drugs – including ibuprofen (Motrin) and naproxen (Aleve, Naprosyn)
• Certain antibiotics – including ciprofloxacin (Cipro), doxycycline (Vibramycin, others), gentamicin (Garamycin), erythromycin (Ery-Tab, others), tetracycline (Sumycin), tobramycin (Nebcin), and vancomycin (Vancocin)
• Antimalarial drugs – such as chloroquine and quinine
• Certain anticonvulsants – including carbamazepine (Tegretol, others) and valproic acid (Depakote, others)
• Certain cancer drugs – including cisplatin (Platinol) and vincristine (Oncovin, Vincasar)
• Loop diuretics – (when given intravenously in high doses), including bumetanide (Bumex), furosemide (Lasix), and torsemide (Demadex)
• Tricyclic antidepressants – such as amitriptyline (Elavil, others), clomipramine (Anafranil), and imipramine (Tofranil)

Anyone can experience tinnitus, but these factors may increase your risk:

• Loud noise exposure – Prolonged exposure to loud noise can damage the tiny sensory hair cells in your ear that transmit sound to your brain. People who work in noisy environments — such as factory and construction workers, musicians, and soldiers — are particularly at risk.
• Age – As you age, the number of functioning nerve fibers in your ears declines, possibly causing hearing problems often associated with tinnitus.
• Sex – Men are more likely to experience tinnitus.
• Smoking – Smokers have a higher risk of developing tinnitus.
• Cardiovascular problems – Conditions that affect your blood flow, such as high blood pressure or narrowed arteries (atherosclerosis), can increase your risk of tinnitus.

Associated factors

Factors associated with tinnitus include:

• ear problems and hearing loss:
  • conductive hearing loss
    • acoustic shock
    • loud noise or music
    • middle ear effusion
    • otitis
    • otosclerosis
    • Eustachian tube dysfunction
  • sensorineural hearing loss
    • excessive or loud noise; e.g. acoustic trauma
    • presbycusis (age-associated hearing loss)
    • Ménière’s disease
    • endolymphatic hydrops
    • superior canal dehiscence
    • acoustic neuroma
    • mercury or lead poisoning
    • ototoxic medications
• neurologic disorders:
  • Arnold–Chiari malformation
  • multiple sclerosis
  • head injury
  • giant cell arteritis
• temporomandibular joint dysfunction
• metabolic disorders:
  • vitamin B₁₂ deficiency
  • iron deficiency anemia
• psychiatric disorders
  • depression
  • anxiety disorders
• other factors:
  • vasculitis
  • Some psychedelic drugs can produce temporary tinnitus-like symptoms as a side effect
    • 5-MeO-DET
    • diisopropyltryptamine (DiPT)
  • benzodiazepine withdrawal
  • intracranial hyper or hypotension caused by, for example, encephalitis or a cerebrospinal fluid leak

Symptoms of Tinnitus

Tinnitus involves the sensation of hearing sound when no external sound is present. Tinnitus symptoms may include these types of phantom noises in your ears:

• Ringing
• Buzzing
• Roaring
• Clicking
• Hissing
• Humming

The phantom noise may vary in pitch from a low roar to a high squeal, and you may hear it in one or both ears. In some cases, the sound can be so loud it can interfere with your ability to concentrate or hear external sound. Tinnitus may be present all the time, or it may come and go.

Diagnosis of Tinnitus

Many modern antineoplastic drugs are ototoxic including bleomycin, cis-platinum, methotrexate, and bumetanide. These cause hearing loss and tinnitus that may not be reversible.

• Ethacrynic acid, acetazolamide, are diuretics listed as ototoxic
• Aspirin in higher doses causes tinnitus. Fortunately, this is reversible. Tinnitus has been reported with other NSAID medications.

Caution must be exercised in evaluating tinnitus from a new drug because of the very high incidence of tinnitus in the population. In a double-blind study, tinnitus may be reported as occurring in the placebo group. When anti-neoplastic drugs are used, regular hearing tests are done to watch for the onset of hearing loss or tinnitus so that the drug can be stopped if possible.

History and Physical

The symptoms of tinnitus include ringing, buzzing, roaring, hissing, or whistling in the ears. The noise may be intermittent or continuous. Most of the time, only the person who has tinnitus can hear it.

A physical exam should focus on the ear and the nervous system. The ear canal should be inspected for discharge, foreign body, and cerumen. The tympanic membrane should be inspected for signs of infection and tumor (red or bluish mass). A bedside hearing test should be done. Cranial nerves, particularly vestibular function, are tested along with peripheral strength, sensation, and reflexes. A stethoscope should be used to listen for vascular noise over the course of the carotid arteries and jugular veins and over and adjacent to the ear.

Evaluation

Your doctor will examine your ears, head and neck to look for possible causes of tinnitus. Tests include:

• Hearing (audiological) exam – As part of the test, you’ll sit in a soundproof room wearing earphones through which will be played specific sounds into one ear at a time. You’ll indicate when you can hear the sound, and your results are compared with results considered normal for your age. This can help rule out or identify possible causes of tinnitus.
• Movement – Your doctor may ask you to move your eyes, clench your jaw, or move your neck, arms and legs. If your tinnitus changes or worsens, it may help identify an underlying disorder that needs treatment.
• Clicking – Muscle contractions in and around your ear can cause sharp clicking sounds that you hear in bursts. They may last from several seconds to a few minutes.
• Rushing or humming – These sound fluctuations are usually vascular in origin, and you may notice them when you exercise or change positions, such as when you lie down or stand up.
• Heartbeat – Blood vessel problems, such as high blood pressure, an aneurysm or a tumor, and blockage of the ear canal or eustachian tube can amplify the sound of your heartbeat in your ears (pulsatile tinnitus).
• Low-pitched ringing – Conditions that can cause low-pitched ringing in one ear include Meniere’s disease. Tinnitus may become very loud before an attack of vertigo — a sense that you or your surroundings are spinning or moving.
• High-pitched ringing – Exposure to a very loud noise or a blow to the ear can cause a high-pitched ringing or buzzing that usually goes away after a few hours. However, if there’s hearing loss as well, tinnitus may be permanent. Long-term noise exposure, age-related hearing loss or medications can cause a continuous, high-pitched ringing in both ears. Acoustic neuroma can cause continuous, high-pitched ringing in one ear.
• Other sounds – Stiff inner ear bones (otosclerosis) can cause low-pitched tinnitus that may be continuous or may come and go. Earwax, foreign bodies or hairs in the ear canal can rub against the eardrum, causing a variety of sounds.
• X-rays and MRI  – are not usually done for tinnitus unless there is an unexplained difference in hearing and balance in the ears.
• An audiogram – is a hearing test measuring hearing levels to determine hearing loss. The patient is asked to match which of the tones matches their tinnitus. The audiologist introduces that sound as to volume, and the patient estimates how loud they hear their tinnitus. Hearing via the bone of the ear is tested and compared with the hearing via the earphone called an air-bone test. If the patient hears better with the bone test, this suggests a condition called otosclerosis which is treatable. Patients with otosclerosis, in whom the stapes fail to move well, can have surgery that corrects the otosclerosis and restores air conduction. In some patients, the tinnitus is relieved. In others, tinnitus remains or becomes worse.

The audiologist measures how long tinnitus is relieved by masking tone. The longer the tinnitus is inhibited, the better the prognosis.[rx][rx][rx]

Treatment of Tinnitus

The American Academy of Otolaryngology has issued clinical practice guidelines for tinnitus. These include:

• Stress Reduction – This includes using biofeedback, measured breathing, etc. Although stress itself is not a cause of tinnitus, as in any condition, stress and anxiety can make the condition worse.
• Cognitive Therapy – The more the patient understands what tinnitus is and is not the less negative effect. Once the patient fully cognizes – understands that tinnitus is similar to itching, the symptoms are reduced.
• Masking – When the body hears the same sound from the cell phone or sound device, this reduces the symptoms.  There are various forms of masking. Essentially these masking sounds take the attention away from the internal tinnitus sound and replace it with relaxing sounds.
• Introduction of the same sound
• Introduction of an altered sound
• Music with the tinnitus sound removed
• White noise or pleasant sounds
• Sleep improvement – Tinnitus can affect normal sleep and therapy should be directed to better sleep hygiene.
• Massage and stretching – Massage and stretching of the neck and masticatory muscles have been associated with significant improvement in tinnitus. Patients with somatic tinnitus can have symptoms of cervical spine disorders, including head, neck, and shoulder pain as well as limitations in sideways bending and rotation. Treating jaw and neck disorders has beneficial effects on tinnitus. Injecting lidocaine into jaw muscles, such as the lateral pterygoid, also reduces tinnitus.
• Electrical suppression – Electrical stimulation of the cochlea with trains of pulses at 5,000 pulses per second can substantially or completely suppress tinnitus with either no perception or only a transient perception of the stimulus. Stimulus with electrical pulses at such a high rate restores spontaneous-like patterns of spike activity in the auditory nerve, which could explain how it suppresses tinnitus.
• Transcutaneous electrical nerve stimulation – of areas of skin close to the ear increases the activation of the DCN via the somatosensory pathway and could augment the inhibitory role played by this nucleus on the CNS, thereby ameliorating tinnitus.
• Music therapy – Music therapy is a desensitization method that utilizes music that has been spectrally modified according to the hearing characteristics of each patient to allow the masking of tinnitus and to facilitate relaxation at a comfortable listening level. Music directly affects the limbic system, bypassing the slower linguistically based processing in the auditory cortex. Hearing thresholds decline substantially above 3 kHz among many tinnitus patients, and hence the spectral modification should involve reducing the energy of lower frequency components of the music.
• Tinnitus retraining therapy – Tinnitus retraining therapy (TRT) is a form of habituation therapy designed to help tinnitus sufferers. TRT mainly targets nonauditory systems, particularly the limbic and autonomic nervous systems, and is based on the assumption that tinnitus represents a side effect of the normal compensatory mechanisms in the brain. TRT uses naturally occurring mechanisms of plasticity in the brain to achieve habituation to the physiological reactions to tinnitus and, subsequently, to achieve habituation to the very perception of tinnitus.

Cognitive and behavioral therapy

Cognitive therapy focuses on how one thinks about tinnitus and on the avoidance of negative ideation, whereas behavioral therapy uses the systematic desensitization approach that is applied to many phobias. Cognitive therapy involves teaching patients to cope with their tinnitus by replacing negative thinking with more positive thinking. Cognitive therapy includes counseling and cognitive restructuring. Counseling should include

• 1) informing patients that it is unlikely that their annoyance with tinnitus will improve dramatically,
• 2) informing patients about the usefulness of tinnitus self-help groups,
• 3) helping patients to minimize the time devoted to activities and/or conditions in which the tinnitus intensity is increased and to maximize the time devoted to activities and/or conditions in which the tinnitus intensity is decreased, and
• 4) stressing the avoidance of noise exposure, since noise-induced hearing loss and tinnitus are related.

To treat your tinnitus, your doctor will first try to identify any underlying, treatable condition that may be associated with your symptoms. If tinnitus is due to a health condition, your doctor may be able to take steps that could reduce the noise. Examples include:

• Earwax removal – Removing impacted earwax can decrease tinnitus symptoms.
• Treating a blood vessel condition – Underlying vascular conditions may require medication, surgery or another treatment to address the problem.
• Changing your medication – If a medication you’re taking appears to be the cause of tinnitus, your doctor may recommend stopping or reducing the drug, or switching to a different medication.

Noise suppression

In some cases white noise may help suppress the sound so that it’s less bothersome. Your doctor may suggest using an electronic device to suppress the noise. Devices include:

• White noise machines – These devices, which produce simulated environmental sounds such as falling rain or ocean waves, are often an effective treatment for tinnitus. You may want to try a white noise machine with pillow speakers to help you sleep. Fans, humidifiers, dehumidifiers and air conditioners in the bedroom also may help cover the internal noise at night.
• Hearing aids – These can be especially helpful if you have hearing problems as well as tinnitus.
• Masking devices – Worn in the ear and similar to hearing aids, these devices produce a continuous, low-level white noise that suppresses tinnitus symptoms.
• Tinnitus retraining – A wearable device delivers individually programmed tonal music to mask the specific frequencies of the tinnitus you experience. Over time, this technique may accustom you to the tinnitus, thereby helping you not to focus on it. Counseling is often a component of tinnitus retraining.

Medication

The official guidelines stress that no medication cures tinnitus. However various combinations of magnesium, alpha-lipoic acid, N-acetyl cysteine, and others have been tested for protection of hearing from noise.[rx][rx]