Although mitochondrial DNA variants are thought to predispose to hearing loss, a study of polish individuals by Lechowicz et al, reported that "there are no statistically significant differences in the prevalence of tinnitus and its characteristic features between HL patients with known HL mtDNA variants and the general Polish population." This would argue against mitochondrial DNA variants as a cause of tinnitus, but the situation might be different in other ethnic groups.
Other causes of tinnitus include middle ear infections, disorders that block the ear canal (such as an external ear infection [external otitis], excessive ear wax, or foreign bodies), problems with the eustachian tube (which connects the middle ear and the back of the nose) due to allergies or other causes of obstruction, otosclerosis (a disorder of excess bone growth in the middle ear), and temporomandibular disorders. An uncommon but serious cause is an acoustic neuroma, a noncancerous (benign) tumor of part of the nerve leading from the inner ear.
Cognitive behavioral therapy (CBT). CBT uses techniques such as cognitive restructuring and relaxation to change the way patients think about and respond to tinnitus. Patients usually keep a diary and perform "homework" to help build their coping skills. Therapy is generally short-term — for example, weekly sessions for two to six months. A 2010 review of six studies by the Cochrane Collaboration (an international group of health authorities who evaluate randomized trials) found that after CBT, the sound was no less loud, but it was significantly less bothersome, and patients' quality of life improved.
Sound-masking devices provide a pleasant or benign external noise that partially drowns out the internal sound of tinnitus. The traditional sound-masking device is a tabletop sound machine, but there are also small electronic devices that fit in the ear. These devices can play white noise, pink noise, nature noises, music, or other ambient sounds. Most people prefer a level of external sound that is just slightly louder than their tinnitus, but others prefer a masking sound that completely drowns out the ringing.
The outlook for tinnitus depends on its cause. In people with tinnitus related to earwax buildup or medications, the condition usually will go away when the earwax is removed or the medication is stopped. In people with tinnitus related to sudden, loud noise, tinnitus may improve gradually, although there may be some permanent noise-related hearing loss.
When there does not seem to be a connection with a disorder of the inner ear or auditory nerve, the tinnitus is called nonotic (i.e. not otic). In some 30% of tinnitus cases, the tinnitus is influenced by the somatosensory system, for instance people can increase or decrease their tinnitus by moving their face, head, or neck. This type is called somatic or craniocervical tinnitus, since it is only head or neck movements that have an effect.
Tinnitus remains a symptom that affects the lives of millions of people. Research is directed not only at its treatment, but also at understanding why it occurs. Research by doctors at the University at Buffalo, The State University of New York, Dalhousie University (Canada), and Southeast China University have published research using electrophysiology and functional MRI to better understand what parts of the brain are involved in hearing and the production of tinnitus. Their research has found that much larger areas of the brain are involved with the process of hearing than previously believed, which may help direct future diagnostic and therapeutic options.
Changes in the bones of the middle ear. A person’s ear is made up of several different bones: the malleus, Incus and Stapes. In some individuals, these bones may actually change shape or harden over the years. This process is known as otosclerosis and often runs in the family. This can cause ringing in the ears to begin or, if it has already started, to get worse over time.
Tinnitus is commonly accompanied by hearing loss, and roughly 90% of persons with chronic tinnitus have some form of hearing loss (Davis and Rafaie, 2000; Lockwood et al, 2002). On the other hand, only about 30-40% of persons with hearing loss develop tinnitus. According to Park and Moon (2004), hearing impairment roughly doubles the odds of having tinnitus, and triples the odds of having annoying tinnitus.
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.
Hearing loss often accompanies tinnitus, so a hearing aid can hit two birds with one stone. In addition to amplifying sound, the device can camouflage the ringing in your ears by boosting other soft sounds in your environment. If you experience hearing loss in addition to your tinnitus, discuss the potential benefits of a hearing aid that may assist with both conditions at the same time.
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.
Ringing-in-the-ears or a fullness-of-the-head sensation are the most common symptoms of tinnitus. While ringing is the most common experience, the noise can also sound like a buzzing, hissing or whizzing sound. It can range from a low pitch to a high pitch and may be soft or loud at times. For some, tinnitus seems to get louder at night, just before sleep when no other sounds are competing with it. Tinnitus can remain constant or come and go intermittently. In severe cases, the ringing in the ears is loud enough to interfere with work or daily activity, whereas those with mild tinnitus can experience soft ringing that is no more than a minor annoyance.