Information AboutTinnitus |
| CATEGORIES ABOUT TINNITUS | |
| otology | |
Tinnitus ( Ear in the absence of corresponding external sound(s). Tinnitus can be perceived in one or both ears or in the head. It is usually described as a ringing noise, but in some patients it takes the form of a high pitched whining (cf. Flyback Transformer ), buzzing, hissing, humming, or whistling sound, or as ticking, clicking, roaring, "crickets" or " Locusts ", tunes, songs, or beeping. RNID.org.uk: Information and resources: Tinnitus: About tinnitus: What is tinnitus It has also been described as a "whooshing" sound, as of wind or waves. Medline Plus Medical Encyclopedia: Ear noises or buzzing Tinnitus is not itself a Disease but a Symptom resulting from a range of underlying causes, including ear infections, foreign objects or wax in the ear, and injury from loud noises. Tinnitus is also a side-effect of some oral medications, such as Aspirin , and may also result from an abnormally low level of Serotonin activity. The sound perceived may range from a quiet background noise to a signal loud enough to drown out all outside sounds. The term "tinnitus" usually refers to more severe cases. Heller and Bergman (1953) conducted a study of 80 tinnitus-free university students placed in a soundproofed room found that 93% reported hearing a buzzing, pulsing or whistling sound. Cohort studies have demonstrated that damage to hearing (among other Health Effects ) from unnatural levels of noise exposure is very widespread in industrialized countries. Noise exposure and subjective hearing symptoms among school children in Sweden Because tinnitus is often defined as a subjective Phenomenon , it is difficult to measure using objective tests, such as by comparison to noise of known frequency and intensity, as in an audiometric test. The condition is often rated clinically on a simple scale from "slight" to "catastrophic" according to the practical difficulties it imposes, such as interference with sleep, quiet activities, or normal daily activities. Guidelines for the Grading of Tinnitus Severity For research purposes, the more elaborate Tinnitus Handicap Inventory is often used. Development of the Tinnitus Handicap Inventory OBJECTIVE TINNITUS In a minority of cases, a clinician can perceive an actual sound (''e.g.'', a . Carotid Artery Dissection MEASURING TINNITUS The basis of this quantitative method, rely on the brain’s capacity of recognizing only the loudest sound. So the tinnitus amplitude is always equal or less than a sampled noise. This works very well in objective tinnitus. For example if a patient has a pulsatile Paraganglioma , in his ear, he will not be able to hear the blood flow through the tumor when the sampled noise is 5 decibel louder than the noise produced by the blood. But the objective tinnitus is quite uncommon, and even patients with pulsatile tumors complains about other coexistent sound, distinct from the pulsatile one, that will persist after tumor ablation… the subjective tinnitus. The subjective tinnitus can’t be measured by this comparative method, because if tested people are focused in the sampled noise, they can reach to comprehensible levels below 5 decibel, which means that the tinnitus is almost impossible to hear. Besides, if the same tested people are focused in tinnitus, they can hear the tinnitus even when test noise is over 70 decibel, which means that the tinnitus is louder than a messy phone ring. This quantification method suggests that subjective tinnitus relates directly with what the patient is attempting to hear. Patients complaining about tinnitus would be people obsessed with their inner sound. This is only partially true because the problem is involuntary. These patients simply can’t override the tinnitus, which is often present in quiet or noisy environments. It’s important to clarify that subjective or simply regular tinnitus is not well correlated with ear malfunction and hearing loss since it is easy to find people with healthy hearing complaining about tinnitus and people almost deaf not complaining. It is also true that tinnitus relates best with memory problems, anxiety, fatigue and a bad healthy status. CAUSES OF SUBJECTIVE TINNITUS Tinnitus can have many different causes, but most commonly results from otologic disorders - the same conditions that cause hearing loss. The most common cause is noise-induced hearing loss, resulting from exposure to excessive or loud noises. Ototoxic drugs can cause tinnitus either secondary to hearing loss or without hearing loss, and may increase the damage done by exposure to loud noise, even at doses that are not in themselves ototoxic. Ototoxic drugs and noise Causes of tinnitus include: Diagnostic approach to tinnitus
MECHANISMS OF SUBJECTIVE TINNITUS One of the possible mechanisms relies in the otoacustic emissions. The Inner Ear contains thousands of minute hairs which vibrate in response to sound waves and cells which convert neural signals back into acoustical vibrations. The sensing cells are connected with the vibratory cells through a neural feedback loop, whose gain is regulated by the brain. This loop is normally adjusted just below onset of self-oscillation, which gains the ear spectacular sensitivity and selectivity. If something changes, it's easy for the delicate adjustment to cross the barrier of oscillation and tinnitus results. This can actually be measured by a very sensitive microphone outside the ear. Other possible mechanisms of how things can change in the ear is damage to the receptor cells. Although receptor cells can be regenerated from the adjacent supporting Deiters cells after injury in birds, reptiles, and amphibians, in mammals it is believed that they can be produced only during Embryogenesis . Although mammalian Deiters cells reproduce and position themselves appropriately for regeneration, they have not been observed to Transdifferentiate into receptor cells except in tissue culture experiments. Supporting cell proliferation after hair cell injury in mature guinea pig cochlea in vivo Mammalian cochlear supporting cells can divide and trans-differentiate into hair cells Therefore, if these hairs become damaged, through prolonged exposure to excessive decibel levels, for instance, then deafness to certain frequencies occurs. In tinnitus, they may falsely relay information at a certain frequency that an externally audible sound is present, when it is not. The mechanisms of subjective tinnitus are often obscure. While it is not surprising that direct trauma to the inner ear can cause tinnitus, other apparent causes (e.g., Temporomandibular Joint Disorder (TMJ) and dental disorders) are difficult to explain. Recent research has proposed that there are two distinct categories of subjective tinnitus: otic tinnitus, caused by disorders of the inner ear or the acoustic nerve, and '''somatic''' tinnitus, caused by disorders outside the ear and nerve but still within the head or neck. It is further hypothesized that somatic tinnitus may be due to "central crosstalk" within the brain, as certain head and neck nerves enter the brain near regions known to be involved in hearing. While most discussions of tinnitus tend to stress physical mechanisms, there is strong evidence that the level of an individual's awareness of their tinnitus can be stress-related, and so should be addressed by improving the state of the nervous system generally, using gradual, unobtrusive, long-term treatments. PREVENTION Tinnitus and hearing loss can be permanent conditions, thus, precautionary measures are advisable. If a ringing in the ears is audible after exposure to a loud environment, such as a rock concert or a work place, it means that damage has been done. Prolonged exposure to noise levels as low as 70 DB can result in damage to hearing ''(see Noise Health Effects )''. If it is not possible to limit exposure, earplugs or ear defenders should be worn. For musicians and DJs, special musicians' earplugs can lower the volume of the music without distorting the sound and can prevent tinnitus from developing in later years. It is also important to check medications for potential Ototoxicity . Ototoxicity can be cumulative between medications, or can greatly increase the damage done by noise. If ototoxic medications must be administered, close attention by the physician to prescription details, such as dose and dosage interval, can reduce the damage done. IngentaConnect Drug-induced Otoxicity: Current Status TREATMENT There are many treatments that are effective for objective tinnitus. But there are no clear effective treatments for subjective tinnitus. Conversely, tinnitus may resolve without any treatment. In the subjective tinnitus the treatment of the associated problems like fatigue, anxiety and a bad healthy status is essential to achieve success. Effective treatments include: ''Objective tinnitus:''
''Subjective tinnitus:''
Although there are no specific cures for tinnitus, anything that brings the person out of the "fight or flight" stress response helps symptoms recede over a period of time. Calming body-based therapies, counseling and psychotherapy help restore well-being, which in turn allows tinnitus to settle. Chronic tinnitus can be quite stressful psychologically, as it distracts the affected individual from mental tasks and interferes with sleep, particularly when there is no external sound. Additional steps in reducing the impact of tinnitus on adverse health consequences include: a review of medications that may have tinnitus as a side effect; a physical exam to reveal possible underlying health conditions that may aggravate tinnitus; receiving adequate rest each day; and seeking a physician's advice concerning a sleep aid to allow for a better sleep pattern. NOTABLE INDIVIDUALS WITH TINNITUS Notable sufferers of tinnitus include :
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