Tinnitus – a sound in the head with no external source – is not a disease; it is a symptom that can be triggered by a variety of different health conditions. So what causes tinnitus? Common sources include hearing loss, ear wax buildup, ototoxic medications, and ear bone changes. No matter what the cause, the condition interrupts the transmission of sound from the ear to the brain. Some part of the hearing system is involved as well, whether the outer, middle, or inner ear.
Pulsatile tinnitus is generally caused by abnormalities or disorders affecting the blood vessels (vascular disorders), especially the blood vessels near or around the ears. Such abnormalities or disorders can cause a change in the blood flow through the affected blood vessels. The blood vessels could be weakened from damage caused by hardening of the arteries (atherosclerosis). For example, abnormalities affecting the carotid artery, the main artery serving the brain, can be associated with pulsatile tinnitus. A rare cause of pulsatile tinnitus is a disorder known as fibromuscular dysplasia (FMD), a condition characterized by abnormal development of the arterial wall. When the carotid artery is affected by FMD, pulsatile tinnitus can develop.
Note however that tinnitus nearly always consists of fairly simple sounds -- for example, hearing someone talking that no one else can hear would not ordinarily be called tinnitus -- this would be called an auditory hallucination. Musical hallucinations in patients without psychiatric disturbance is most often described in older persons, years after hearing loss.
The most common noise is the sound of rapid or turbulent blood flow in major vessels of the neck. This abnormal blood flow may occur because of a reduced red blood cell count (anemia) or a blockage of the arteries (atherosclerosis) and may be worsened in people with poorly controlled high blood pressure (hypertension). Some small tumors of the middle ear called glomus tumors are rich in blood vessels. Although the tumors are small, they are very near the sound-receiving structures of the ear, and blood flow through them can sometimes be heard (only in one ear). Sometimes, blood vessel malformations that involve abnormal connections between arteries and veins (arteriovenous malformations) develop in the membrane covering the brain (the dura). If these malformations are near the ear, the person sometimes can hear blood flowing through them.
While tinnitus is as varied as its causes, it can be grouped into two categories: tonal and non-tonal. Tonal tinnitus is more common and describes the perception of a near-continuous sound or overlapping sounds with a well-defined frequency (e.g., whistling, ringing, buzzing). Non-tonal forms of tinnitus include humming, clicking, crackling, and rumbling.
The use of sound therapy by either hearing aids or tinnitus maskers helps the brain ignore the specific tinnitus frequency. Although these methods are poorly supported by evidence, there are no negative effects. There is some tentative evidence supporting tinnitus retraining therapy. There is little evidence supporting the use of transcranial magnetic stimulation. It is thus not recommended. As of 2017 there was limited evidence as to whether neurofeedback is or is not helpful.
Noise-induced hearing loss - Exposure to loud noises, either in a single traumatic experience or over time, can damage the auditory system and result in hearing loss and sometimes tinnitus as well. Traumatic noise exposure can happen at work (e.g. loud machinery), at play (e.g. loud sporting events, concerts, recreational activities), and/or by accident (e.g. a backfiring engine.) Noise induced hearing loss is sometimes unilateral (one ear only) and typically causes patients to lose hearing around the frequency of the triggering sound trauma.
Tinnitus is a ringing, buzzing, hissing, swishing, clicking, or other type of noise that seems to originate in the ear or head. Most of us will experience tinnitus or sounds in the ears at some time or another. According to the National Institute on Deafness and Other Communication Disorders (NIDCD), about 10% of adults in the U.S. - nearly 25 million Americans - have experienced tinnitus lasting at least five minutes in the past year. Tinnitus is identified more frequently in white individuals, and the prevalence of tinnitus in the U.S. is almost twice as frequent in the South as in the Northeast.
Avoid a too-quiet bedroom. People with tinnitus may find it easier to sleep in a less quiet bedroom, and may benefit from white noise or other sleep-friendly sounds that help mask and minimize their tinnitus. To my patients who are looking to introduce soothing sounds to their sleep environment, I recommend the iHome Zenergy Sleep System, which combines relaxing sounds with aromatherapy and sleep-promoting light therapy.
Meniere’s disease isn’t directly connected to tinnitus, but people with Meniere’s often experience it, at least temporarily. Meniere's disease is an inner ear disease that typically only affects one ear. This disease can cause pressure or pain in the ear, severe cases of dizziness or vertigo and a ringing or roaring tinnitus. While Meniere’s isn’t fully understood, it appears that several relief options for tinnitus can also help with this disease. Patients are often advised to reduce stress and lower their consumption of caffeine and sodium.