With respect to incidence (the table above is about prevalence), Martinez et al (2015) reported that there were 5.4 new cases of tinnitus per 10,000 person-years in England. We don't find this statistic much use as tinnitus is highly prevalent in otherwise normal persons. It seems to us that their study is more about how many persons with tinnitus were detected by the health care system -- and that it is more a study of England's health care system than of tinnitus.
Most tinnitus is "sensorineural," meaning that it's due to hearing loss at the cochlea or cochlear nerve level. But tinnitus may originate in other places. Our bodies normally produce sounds (called somatic sounds) that we usually don't notice because we are listening to external sounds. Anything that blocks normal hearing can bring somatic sounds to our attention. For example, you may get head noise when earwax blocks the outer ear.
It is possible that the most common cause of pulsatile tinnitus is sigmoid sinus diverticulum and dehiscence, which can be collectively referred to as sinus wall abnormalities or SSWA. The sigmoid sinus is a blood carrying channel on the side of the brain that receives blood from veins within the brain. The blood eventually exits through the internal jugular vein. Sigmoid sinus diverticulum refers to the formation of small sac-like pouches (diverticula) that protrude through the wall of the sigmoid sinus into the mastoid bone behind the ear. Dehiscence refers to absence of part of the bone that surrounds the sigmoid sinus in the mastoid. It is unknown whether these conditions represent different parts of one disease process or spectrum, or whether they are two distinct conditions. These abnormalities cause pressure, blood flow, and noise changes within the sigmoid sinus, which ultimately results in pulsatile tinnitus. Narrowing of the blood vessel that leads into the sigmoid sinus, known as the transverse sinus, has also been associated with pulsatile tinnitus.
Though the exact cause of tinnitus — as in the specific mechanism that creates these phantom sounds in some people — remains unknown, contributing factors and triggers have been identified. Excessive exposure to loud noise is often a factor because of the damage done to your auditory system. Tinnitus may also result from jaw-joint dysfunction (e.g., teeth grinding, temporomandibular joint disorder) or chronic neck muscle strain.
Prolonged exposure to loud sounds is the most common cause of tinnitus. Up to 90% of people with tinnitus have some level of noise-induced hearing loss. The noise causes permanent damage to the sound-sensitive cells of the cochlea, a spiral-shaped organ in the inner ear. Carpenters, pilots, rock musicians, street-repair workers, and landscapers are among those whose jobs put them at risk, as are people who work with chain saws, guns, or other loud devices or who repeatedly listen to loud music. A single exposure to a sudden extremely loud noise can also cause tinnitus.
Tinnitus can vary a lot between individuals; therefore you can find many different types of tinnitus. Tinnitus varies considerably in intensity and type. Some people describe tinnitus as high-frequency whistling sounds while others perceive tinnitus as a buzzing noise or a sound similar to butter sizzling in a frying pan. But some experience, instead, a thumping sound in the same rhythm as their heartbeat. This is called pulsatile tinnitus. Read more about the types of tinnitus.
Supporting the idea that central reorganization is overestimated as "the" cause of tinnitus, a recent study by Wineland et al showed no changes in central connectivity of auditory cortex or other key cortical regions (Wineland et al, 2012). Considering other parts of the brain, Ueyama et al (2013) reported that there was increased fMRI activity in the bilateral rectus gyri, as well as cingulate gyri correlating with distress. Loudness was correlated with values in the thalamus, bilateral hippocampus and left caudate. In other words, the changes in the brain associated with tinnitus seem to be associated with emotional reaction (e.g. cingulate), and input systems (e.g. thalamus). There are a few areas whose role is not so obvious (e.g. caudate). This makes a more sense than the Wineland result, but of course, they were measuring different things. MRI studies related to audition or dizziness must be interpreted with great caution as the magnetic field of the MRI stimulates the inner ear, and because MRI scanners are noisy.
Dr. Ben Wedro practices emergency medicine at Gundersen Clinic, a regional trauma center in La Crosse, Wisconsin. His background includes undergraduate and medical studies at the University of Alberta, a Family Practice internship at Queen's University in Kingston, Ontario and residency training in Emergency Medicine at the University of Oklahoma Health Sciences Center.
When tinnitus is unexpected and unwelcomed, it can lead to a negative reaction to the tinnitus. This can create a vicious cycle. When tinnitus is perceived, it can prompt emotions, including frustration, fear, unhappiness, etc. These can, in turn, cause physical reactions such as anxiety and stress. This reinforces the tinnitus and perpetuates the cycle.
Repeated loud noise exposure can be a cause of tinnitus as well as hearing loss. Loud music may cause short term symptoms, but repeated occupational exposure (for example, musicians, factory and construction workers) requires less intense sound levels to cause potential hearing damage leading to tinnitus. Minimizing sound exposure, therefore, decreases the risk of developing tinnitus. Sound protection equipment, like acoustic ear-muffs, may be appropriate at work and at home when exposed to loud noises.
Imagine you’re settling in for a night’s rest. In your quiet bedroom, you’re tune right into those tinnitus noises—and you can’t shake your focus on them. You start to wonder about how you’ll ever fall asleep with these sounds in your ears. You think about the rest you’re missing out on because you’re not already asleep, and you wonder how you’ll have the energy to make it through your day.
People with warning signs should see a doctor right away. People without warning signs in whom tinnitus recently developed should call their doctor, as should people with pulsatile tinnitus. Most people with tinnitus and no warning signs have had tinnitus for a long time. They can discuss the matter with their doctor and be seen at a mutually convenient time.
CBT could potentially help people with tinnitus deal with fears that their tinnitus might be caused by brain damage or might lead to deafness. During CBT, they might learn that the condition is common and that it is not associated with brain damage or deafness. They might also be exposed to the sound in a safe environment, so that it has less of an impact on their daily life. CBT also involves techniques such as applied relaxation and mindfulness training.
For some people, the jarring motion of brisk walking can produce what is called a seismic effect which causes movement in the small bones or contractions in the muscles of the middle ear space. You can experiment to find out if this is the cause by walking slowly and smoothly to see if the clicking is present. Then, try walking quickly and with a lot of motion to see if you hear the clicking. You can also test for the seismic effect by moving your head up and down quickly.