Hearing Page Page last modified:
January 9, 2008
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Timothy C. Hain,
MD. Hearing Page Page last modified:
January 9, 2008
Tinnitus (pronounced "tin-it-tus") is an abnormal noise in the ear (note that it is not an "itis" -- or inflammation). Tinnitus is common -- nearly 36 million Americans have constant tinnitus and more than half of the normal population has intermittent tinnitus.
About six percent of the general population has what they consider to be "severe" tinnitus. That is a gigantic number of people ! In a large study of more than 2000 adults aged 50 and above, 30.3% reported having experienced tinnitus, with 48% reporting symptoms in both ears. Tinnitus had been present for at least 6 years in 50% of cases, and most (55%) reported a gradual onset. Tinnitus was described as mildly to extremely annoying by 67%.(Sindhusake et al. 2003)
Tinnitus can come and go, or be continuous. It can sound like a low roar, or a high pitched ring. Tinnitus may be in both ears or just in one ear. Seven million Americans are so severely affected that they cannot lead normal lives.
The most common types of tinnitus are ringing or hissing ringing, whistling (high pitched hissing) and roaring (low-pitched hissing). Some persons hear chirping, screeching, or even musical sounds.
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, but they have also been reported in lesions of the dorsal pons (Schielke et al, 2000).
Tinnitus is commonly accompanied by hearing loss. Less commonly, it may be accompanied by hyperacusis (an abnormal sensitivity to sound).
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| Structures of the ear. Most tinnitus is due to damage to the cochlea (#9 above) |
Most tinnitus comes from damage to the inner ear, specifically the cochlea (the snail like thing on the right labeled '9').
Patients with Meniere's disease often describe a low pitched tinnitus resembling a hiss or a roar.
Loud noise is the leading cause of damage to the inner ear. Most patients with noise trauma describe a whistling tinnitus (Nicholas-Puel et al,. 2002). In a large study of tinnitus, avoidance of occupational noise was one of two factors most important in preventing tinnitus (Sindhusake et al. 2003). The other important factor was the rapidity of treating ear infections.
Advancing age is often accompanied by inner ear damage and tinnitus. (Sindhusake et al. 2003)
Ear wax can rarely cause tinnitus. Other causes include middle ear infection or fluid, otosclerosis, and infections such as otosyphilis or labyrinthitis,
There are small muscles in the middle ear (the tensor tympani and stapedius) that can start twitching and cause tinnitus (Golz et al. 2003), more about this later.
Patients with head or neck injury may have particularly loud and disturbing tinnitus (Folmer and Griest, 2003). Tinnitus due to neck injury is the most common type of "somatic tinnitus". Somatic tinnitus means that the tinnitus is coming from something other than the inner ear. Tinnitus from a clear cut inner ear disorder frequently changes loudness or pitch when one simply touches the area around the ear. This is thought to be due to somatic modulation of tinnitus. This link contains a good chapter on somatic tinnitus.
Some persons with severe TMJ (temporo-mandibular joint) arthritis have severe tinnitus. Generally these persons say that there is a "screeching" sound. This is another somatic tinnitus. TMJ is extremely common -- about 25% of the population. The exact prevalence of TMJ associated tinnitus is not established, but presumably it is rather high too.
It is also very common for jaw opening to change the loudness or frequency of tinnitus. This is likely a variant of somatic modulation of tinnitus (see above). The sensory input from the jaw evidently interacts with hearing pathways.
Tinnitus can also arise from damage to the nerve between the ear and brain (8th nerve, labeled 6, auditory nerve). Distinct causes are microvascular compression syndrome, viral infections of the 8th nerve, and tumors of the 8th nerve.
Tinnitus arises more rarely from injury to the brainstem (Lanska et al, 1987), and extremely rarely, to the brain itself (e.g. palinacusis).
In pulsatile tinnitus, people hear something resembling their heartbeat in their ear.
Pulsatile tinnitus is usually due to a small blood vessel that is coupled by fluid to your ear drum. It is usually nothing serious and also untreatable. Nevertheless, rarely pulsatile tinnitus can be caused by more serious problems -- aneurysms, increased pressure in the head (hydrocephalus), and hardening of the arteries. A vascular tumor such as a "glomus" may fill the middle ear, or a vein similar to a varicose vein may make enough noise to be heard.
There are some very large blood vessels -- the carotid artery and the jugular vein -- that are very close to the inner ear (see diagram above). Noise in those blood vessels can be conducted into the inner ear. Accordingly, other possibilities for vascular tinnitus include dehiscence (missing bone) of the jugular bulb -- an area in the skull which contains the jugular vein, and an aberrantly located carotid artery. An enlarged jugular bulb on the involved side is common in persons with venous type pulsatile tinnitus.
Anything that increases blood flow or turbulence such as hyperthyroidism, low blood viscosity (e.g. anemia), or tortuous blood vessels may cause pulsatile tinnitus.
In our opinion, people are very quick to blame drugs for their tinnitus, but it is rare that this is borne out.
Many medications also can cause tinnitus (see list below). Generally this is thought to arise from their effect on the cochlea (inner ear).
Drugs that commonly cause or increase tinnitus -- these are largely ototoxins.
Often people bring in very long lists of medications that have been reported, once or twice, to be associated with tinnitus. This unfortunate behavior makes it very hard to care for these patients -- as it puts one into an impossible situation where the patient is in great distress but is also unwilling to attempt any treatment. Specialists who care for patients with ear disease, usually know very well which drugs are problems (such as those noted above), and which ones are nearly always safe.
Vitamin B12 deficiency is common in tinnitus patients.
Persons with tinnitus should be seen by a physician expert in ear disease, usually an otologist or a neurotologist.
There should be an examination of the ears with an otoscope. Wax should be removed, and the examiner should note whether the ear drum is intact, inflamed, scarred, or whether it is moving.
The eyes should be examined for papilloedema (swelling of a portion of the back of the eye called the "optic disk") as increased intracerebral pressure can cause tinnitus. Because papilloedema is so rare, and tinnitus is so common, it is very unusual to find this dangerous condition.
The TMJ joints of the jaw should be checked as about 28% of persons with TMJ syndrome experience tinnitus. TMJ is very common too.
Inspection of the eardrum may sometimes demonstrate subtle movements due to contraction of the tensor tympani (Cohen and Perez, 2003). Tensor tympani myoclonus causes a thumping sound.
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| Cartoon of the middle ear showing muscles that attach to ossicles (ear bones), and ear drum. The stapedius is attached to the stapes (of course -- horseshoe object above), while the tensor tympani is attached to the ear drum. With permission, from: http://www.meddean.luc.edu/lumen/meded/grossanatomy/dissector/mml/images/stap.jpg |
The tensor tympani syndrome is fairly common. It sometimes results in visible contractions of the ear drum, and produces sounds audible to the examiner. Patients usually indicate that it makes a "thumping" noise -- like a tympani ! An impedance bridge (tympanometer) can document rhythmic changes in ear drum compliance. A and a long recording of ear drum compliance should be made with a tympanometer (a screener won't work here).
There should not be movement of the palate in the stapedius myoclonus syndrome, as the stapedius does not insert onto the eardrum but rather onto the stapes.
In our experience (see recording below), the sound can be heard from the outside -- it is a high-pitched "tic". We were unable to hear with a stethascope however, possibly due to it's high pitch. There was no visible movement of the eardrum, in this case.
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| Rhythmic changes in impedance of the middle ear. Each bump was correlated with a high-pitched "tic" that can be heard from the outside, due to stapedius myoclonus. |
Click below to play recording of stapedius myoclonus.
The audiogram sometimes shows a sensorineural deficit due to masking from the tinnitus.
Tympanograms can sometimes show a rhythmic compliance change due to a middle ear vascular mass or due to contraction of muscles in the middle ear. An ABR test may be helpful in diagnosing tinnitus due to a tumor of the 8th nerve or tinnitus due to a central process. A brain MRI is used for the same general purpose and covers more territory.
The physician may also request an OAE test (which is very sensitive to noise induced hearing damage), BAER test (clicks in ears for damage to the cochlear nerve), an ECOG (looking for Meniere's disease and hydrops, an MRI/MRA test (scan of the brain), a VEMP, and several blood tests (ANA, B12, FTA, ESR, SMA-24, HBA-IC, fasting glucose, TSH, anti-microsomal antibodies).
We occasionally recommend neuropsychological testing using a simple screening questionnaire -- depression, anxiety, and OCD (obsessive compulsive disorder) are common in persons with tinnitus. This is not surprising considering how disturbing tinnitus may be to ones life. Persons with OCD tend to "obsess" about tinnitus. Treatment of these conditions may be extremely helpful.
In persons with pulsatile tinnitus, additional tests maybe proposed to study the blood vessels and to check the pressure inside the head. Gentle pressure on the neck can be performed to block the jugular vein but not the carotid artery. The Valsalva maneuver reduces venous return by increasing intrathoracic pressure. If there is a venous hum, this usually abates or improves markedly. If the pulsation is arterial, these tests have no effects. MRI/MRA or CT is often suggested in younger patients with unilateral pulsatile tinnitus. In older patients, pulsatile tinnitus is often due to atherosclerotic disease and it is less important to get an MRI/MRA. A lumbar puncture may be considered if there is a possibility of benign intracranial hypertension. More invasive testing includes the "balloon occlusion test", where a balloon is blown up in the internal jugular vein to see if it eliminates tinnitus.
Vestibular tests such as ENG or posturography are generally not helpful in diagnosing tinnitus. Tinnitus is rarely attributable to sinus disease and even if tests suggest that you have this common condition, it is unlikely that treatment of it will affect tinnitus.
Based on these tests, tinnitus can be separated into categories of cochlear,
retrocochlear, central, and tinnitus of unknown cause.
The bottom line is that most people "get used" to tinnitus, and learn to "tune it out". It is unusual (although not impossible) for people to get substantial relief from medication, devices, or surgery. "Obsessing" about tinnitus, generally tends to make it more persistent and worse. Thus doctors tend to discourage reading of web pages like this one, or joining of support groups. The treatments that work the best for tinnitus are those that alter ones emotional state -- antidepressants and antianxiety drugs, and ones that allow you to get a full night's sleep.
The bad news in more detail : Dobie (1999) reviewed the 69 randomized controlled trials of tinnitus treatments. According to Dr. Dobie, no treatment can yet be considered "well established" in terms of providing replicable long-term reduction of tinnitus impact, in excess of placebo effects. Support and counseling are probably helpful as are tricyclic antidepressants in severe cases. Benzodiazepines, newer antidepressants and electrical stimulation deserve further study. But don't lose all hope: Dobie made the point that tinnitus is likely multifactorial, and the usual study design is likely not well chosen for this situation. A study design where initially an open-label study is performed, followed by a randomized placebo controlled trial might find patient groups that respond to a medication. This seems very logical.
If a specific cause for tinnitus is found, then your doctor may be able to eliminate the noise. Examples of specific causes include medication, tumors, infections, Meniere's disease, TMJ and otosclerosis. Tinnitus due to the tensor tympani can be treated by transection of that muscle. To find a specific cause it may require a fairly extensive workup including X-rays and blood tests. However, even after extensive workup, most causes of tinnitus go undiagnosed.
If a specific cause of tinnitus is not found, it is unlikely that the tinnitus can be gotten rid of. At best, one might get partial relief from some of the strategies to be described in the next few paragraphs. However, even though treatment may not be available, tinnitus should be checked into, as tinnitus may be a warning sign of a serious disorder such as a tumor of the 8th nerve, or other disorder which may impair hearing. Tinnitus does tend to gradually get better, but many persons with severe tinnitus still experience distress 5 years later. Tolerance of tinnitus increases with time. (Andersson et al, 2001).
Medications may occasionally help lessen the noise even though no cause can be found. In general, we are not at all enthused about medication treatment as the side effects can be substantial and the results are often unimpressive. In randomized clinical trials, for the most part, the agents under study have failed to demonstrate elimination of tinnitus more frequently than have placebos (Dobie RA, 1999). Medications to deal with the psychological fallout of tinnitus is often useful -- antidepressants and anti-anxiety medications can be very helpful.
Medications that are well accepted in treatment of Tinnitus
Comment. Benzodiazepines and tricyclics probably mainly change emotional responses to tinnitus. Any sort of relief, however, is important.
We have also had some patients get relief from other antidepressants including the SSRI family.
The anticonvulsants such as mysoline may affect some patients who have tinnitus due to 8th nerve irritation. Mysoline contains phenobarbital, which is sedating.
The effect of local anesthetics on tinnitus was discovered serendipitously by Barany in 1935. Otsuka et al (2003) recently reported administration of Lidocaine to 117 ears over a 24 year period. The method was intravenous infusion, of between 80 and 100 mg. They report a transient (several minutes) response in about 70% of treated ears. As responses are nearly always very temporary, lidocaine does not have a role as a treatment of tinnitus. The mechanism appears to be central (Baguley et al, 2005). According to Dobie (1999), the related drugs tocainamide, mexilitine and flecainamide have not been shown superior to placebo.
Atorvastatin (Lipitor). A recent trial in older people showed that atorvastatin had no effect on the rate of hearing deterioration but there was a trend toward improvement in tinnitus scores over several years. (Olzowy et al, 2007)
Campral, is a medication FDA approved for treatment of abstinent alcoholics. A paper from south america reported that it is effective for tinnitus. This is an off-label use of this medication. At this writing (4/8/07), it is too soon to know if it is effective. We have tried it in a few patients -- and are still not sure if it is helpful. Because it is easily available in the US, and has a rather benign side effect profile, we think that it is a good candidate for medication trials.
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| Homeopathic preparation for tinnitus -- contains aspirin ! Most if not all homeopathic preparations are placebos. |
Comment: Some of these drugs may be worth considering depending on ones personal situation. The ones with the least adverse effects would seem most logical. If one understands the mechanism of one's tinnitus, it seems more likely that a drug like this might work.
Hearing aids and other devices called "maskers" may also help alleviate tinnitus. This is a tricky business. If you have tinnitus associated with a hearing loss, a hearing aid is a reasonable thing to try. Be sure that you try the hearing aid before buying one, as tinnitus is not always helped by an aid. We see no reason to get 2 hearing aids at the same time, for treatment of tinnitus. Nearly all states mandate a 1-month money-back guarantee built into hearing aid dispensing.
It also seems possible that a hearing aid might exacerbate tinnitus, as many people develop "ringing" of their ears after exposure to loud noise.
Maskers are based on the idea that tinnitus is usually worst when things are very quiet. Listening to the interstation static on the FM radio, tapes of ocean surf, fans, and the like may be helpful. Pillow speakers sold by Radio Shack may be helpful in order to avoid disturbing others. This is a very cheap method.
Tinnitus maskers are fitted and sold by audiologists. Controlled studies of maskers have shown small effects (Dobie, 1999).
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| Neuromonics device -- Ipod in disguise ? |
There are many devices that have been offered as treatments for tinnitus. One of the most recent is the Neuromonics device. It is presently being sold in the US, through select audiologists, for about $5000. This device resembles a "Ipod" player, and even comes with premium headphones ! Unfortunately, you can't use the device to play anything other than preprogrammed cartridges, that we are told, sound somewhat like "new age" music.
It is too soon to say whether or not this device is effective. In our conversations with patients who use this device, they generally think (after many months of listening and counseling visits to the dispensing audiologist) that it is slightly helpful.
Davis, Paki (2007), recently published an article in Ear Hear, indicating that it is the 3rd clinical trial for this device. I was unable to find any other references containing the word Neuromonics in PubMed, so evidently the first 2 trials were not published. This study, which appears to be done by the inventors or perhaps the manufactorers of the device, is small (n=35), unblinded and uncontrolled. The claims for the device are rather amazing, and the opportunities for bias are substantial.
We hope that rigorous studies will follow as the general idea that listening to something that gives you pleasure and sounds somewhat like your tinnitus may "desensitize" you to your tinnitus, seems very reasonable. On the other hand, we are not sure why one should have to pay $5000 for an Ipod with a single song.
It would seem to us that given that this approach is slightly useful (and we suspect that it is, although proof would be nice), a do-it-yourself strategy might work equally well for a small fraction of the cost. What you would need is to have an audiologist do "tinnitus matching", to find out what you are trying to duplicate, and also have someone provide you with music that you want to listen to 24/7, selected to make sure that it overlaps with the frequency spectrum of your tinnitus.
In general, whether you are considering buying a "Neuromonics" device, a magnetic or electrical device or ultrasound generators, we advise extreme caution in situations where someone suggests to you that an extremely expensive device, with an unclear principle of action, may cure your tinnitus. There is a very long history of placebos for subjective complaints such as dizziness and tinnitus. As the Romans said, "caveat emptor" (buyer beware!).
Acupuncture. This probably a placebo treatment although acupuncture is preferred to placebo (Dobie, 1999).
Electrical stimulation. Two randomized controlled trials in the 1980's found a device ineffective compared with a placebo (Dobie, 1999). There is probably no harm other than to the pocketbook.
Electromagnetic stimulation. Again, no help for the simple devices. (Ghossaini et al, 2004). However, see the TMS entry below for the high intensity version.
Magnetic Stimulation: Of course, magnetic head-bands or the like are almost certainly placebos. Little data is available (Dobie, 1999)
TMS -- transcranial magnetic stimulation. This is an investigational approach, which presently is promising. TMS involves brain stimulation using very high intensity magnetic pulses. It is somewhat similar to a "gentle" electroshock treatment, and clearly works on the brain rather than the inner ear. TMS seems to be somewhat helpful for depression and migraine, and one would think that a modality that worked for these, would also work to some extent for tinnitus. There is presently some evidence that it is helpful (Smith et al, 2007; Kleingjung et al, 2007). This treatment is available only in persons who are in research environments.
Ultrasound: No difference from placebo (Dobie, 1999)
Again, bad news. Surgery should be considered when there is a clear structural reason for tinnitus that can be improved with surgery. It is also worth considering if hearing can be improved by surgery. Generally though, hearing aids or implantable devices are much more successful than surgery.
A very rare example of surgically treatable tinnitus is tinnitus due to a tumor.
Venous tinnitus is tinnitus due to a venous source (usually pulsatile in this situation). For venous tinnitus, possibilities include jugular vein ligation, occlusion of the sigmoid sinus, or closure of a dural fistula.
Surgery may also be an option to consider if your diagnosis is otosclerosis, fistula
Occasionally persons with Meniere's disease have relief or reduction of tinnitus from transtympanic gentamicin.
Microvascular compression syndrome, in theory, may cause tinnitus, but we have had very little success when the few patients we have seen with this syndrome have undergone surgery.
Shunt surgery for hydrocephalus, may be helpful for this very rare cause.
Rarely 8th nerve sections are done for tinnitus. They are successful in about 50%, with the price of losing hearing in 100%.
Diet: We recommend that persons with tinnitus limit salt (no added salt), and refrain from drinking caffeinated beverages, other stimulants (like tea), and chocolate. The salt restriction is intended for those who might have a subclinical form of Meniere's. Caffeine and similar substances increase tinnitus in a nonspecific fashion. Otherwise the diet should be balanced and have normal amounts of fruits and vegetables.
Alternative medicine approaches. Ginkgo-Biloba, betahistine (Serc), Zinc, and acupuncture are sometimes advocated as treatment for intractable tinnitus. There is little evidence that these agents work, but they also do not seem to be harmful. In our clinical practice, we have occasionally encountered persons with very good responses to betahistine. More discussion about alternative medications is available here.
Psychological help: Often, anxiety or depression which accompanies tinnitus may be as big a problem as the tinnitus itself. In this instance, consultation with a psychologist or psychiatrist expert in this field may be helpful. Hypnosis may be effective and increase tolerance to tinnitus, but randomized controlled trials are not encouraging (Dobie, 1999). If you can ignore tinnitus rather than obsess about it, this may be the best way to handle it. Medications that help people with obsessive compulsive disorder (such as the SSRI family) may be helpful.
Self Help: You might consider joining the American Tinnitus Association. (PO Box 5, Portland, OR 97207, 503-248-9985). However, if your tinnitus has been well "worked up", and there is nothing more to be done, it might be best to attempt to ignore it rather than focus more attention on it.
Tinnitus Retraining Therapy (TRT). This method of habituation of tinnitus is helpful for some (Wang et al, 2003). It requires a considerable commitment of time. We sometimes refer patients for this.
As of 4/2002, a visit to the National Library of Medicine's search engine, Pubmed, revealed more than 3,900 research articles concerning tinnitus published since 1966. In spite of this gigantic effort, very little is presently known about tinnitus, and often effective treatment is unavailable.
| © Copyright May 11, 2008 , Timothy C. Hain, M.D. All rights reserved. Last saved on May 11, 2008 |
