Tinnitus is itself not a disease, but rather it is a symptom that can be caused by a range of other conditions. In tinnitus the patient will suffer from sounds and particularly ‘ringing’ heard in the ear (the word tinnitus actually translates from Latin as ringing) despite there usually being no corresponding sound in reality. This is not a hallucination but rather a result of damaged hearing and most commonly noise-induced hearing loss. For some this can be a minor irritation, but in more extreme cases it can be highly distressing and cause depression, mood swings, headaches and difficulty concentrating and sleeping.
The nature of the ringing noise varies. It can be perceived in either one or both ears and is in most cases described as a ‘ringing’ though it can also take the form of whining, buzzing, hissing, humming, tingling, whistling, clicking, roaring, ticking, beeping, steady tones, scratching and more. In some rare cases it may even sound like talking or music. Tinnitus may be intermittent, or it may be continuous. Sometimes the intensity of the noise is related to physical position.
As the sounds are ‘internal’ as it were however, measuring the amplitude of tinnitus effects and the nature can be difficult as it is difficult to compare them to outside measures. Usually tinnitus is accompanied by hearing loss.
To be diagnosed with tinnitus, other potential causes for the sounds must be ruled out. This includes ‘Radio Frequency Hearing’ in which patients are found to be able to actually ‘hear’ high pitched radio transmission frequencies. Signal transmissions and electromagnetic fields must also be ruled out. While it is difficult to measure the severity of the sounds themselves, it is easier to measure the amount of distressed caused by them which can be achieved using the Tinnitus Handicap Inventory.
There are two main types of tinnitus which are ‘objective’ and ‘subjective’. Objective tinnitus is interesting in that a clinician can actually perceive the sound emanating from the subjects ears. This can be the result of muscle spasms in the ears which are most likely to cause clicks of crackling noises around the middle of the ear. Some people will also experience ‘pulsatile tinnitus’ which is usually objective and is normally in time with the pulse caused by blood flow. In some cases this can be a sign of life threatening conditions such as carotid artery aneurysm or carotid artery dissection, so it is very important to have any pulsatile tinnitus checked out as soon as possible.
Subjective tinnitus meanwhile is that which a clinician cannot detect and is most commonly caused by exposure to excessive loud noises.
There are many potential causes of subjective tinnitus, which include: ear infections, foreign objects in the ears, nasal allergies, build up of wax, withdrawal from medications (such as benzodiazepine), injury, loud noises and more. In some cases tinnitus is part and parcel of a normal hearing impairment associated with age related decline. The most common cause however is noise induced hearing loss.
There are many mechanisms for subjective tinnitus which is a result of the complex nature of our hearing. The inner ear contains thousands of microscopic hair cells which vibrate in accordance with sound. This is then converted into neural signals via a vibrating basement membrane. Sensing cells are connected to these vibratory cells via a ‘neural feedback loop’. This is adjusted so that it is just below the onset of ‘self oscillation’ which keeps it sensitive but at the same time selective. Damage however can alter this ‘basal level’ to the point where tinnitus occurs.
Studies meanwhile have shown that listening to loud music for long durations can have many negative effects on our hearing systems – causing the loss of hair cells, and the activation of different neurons. In other cases the damage may occur to the receptor cells. However while these mechanisms are relatively easy to understand, some of the other apparent causes for tinnitus – such as dental disorders – currently have no wholly accepted explanation.
As there are many causes and forms of tinnitus, treatments too are highly varied. For instance gamma knife radiosurgery, shielding of the cochlea through the implantation of teflon, botulinum toxin to prevent palatal tremor, clearing the ear canal and using a neurostimulator have all found varying success for treating objective tinnitus.
For subjective a range of medications and surgical options are available and studies are being continued in this area. Electrical stimulation of the auditory cortex through implanted electrodes for instance can help to prevent tinnitus at a neural level, meanwhile repair of the perilymph fistula through surgery has been found to be helpful. However the success of treatment will vary greatly depending on the precise nature of the tinnitus. In cases where the tinnitus is the result of another underlying condition then treatment of that condition may help to alleviate the tinnitus symptoms.
There are also many ways that tinnitus can be managed in order to help patients to cope with the noise. It is recommended for instance that patients avoid caffeine and other stimulants. Those who have difficulty sleeping might opt to use melatonin or other sleeping aids. Avoidance of other outside noise sources is also recommended.
The use of external sound has also found success in some cases. Particularly the use of low pitched sound treatment has had promising findings. Some sufferers choose also to use a ‘tinnitus masker’ which creates loud white noise in order to ‘mask’ the sound. Even just pleasant music can help to act as a distraction.
In Tinnitus Retraining Therapy patients meanwhile are taught to alter the way they respond to tinnitus and to better understand its nature.