Tinnitus (tinnitus) is a subjective symptom in which the patient perceives a sound in the ear or skull without the presence of a corresponding sound source or electrical stimulus in the surrounding environment. The mechanism of tinnitus is unclear, the cause is complex, the patient is suffering, and the cure is difficult. In a few cases, tinnitus is a symptom and a causal relationship between tinnitus and a known disease can be established. The basic principle of treatment for this type of tinnitus is to identify and treat the primary cause. The basic principle of treatment for this type of tinnitus is to identify and treat the primary cause. In most cases, tinnitus is a disease that causes insomnia, irritability, anxiety, depression and other symptoms of varying degrees due to tinnitus as the first complaint, which affects work, study, life and emotion to varying degrees, and cannot be explained by known diseases. This kind of idiopathic tinnitus is caused by multiple factors and can be accompanied by auditory hypersensitivity.
Because tinnitus can be associated with psychiatric or functional disorders, it is sometimes easily overlooked as a functional symptom, leaving patients without early examination and treatment, and even delaying the diagnosis and treatment of the disease.
It is estimated that nearly 40 to 50 million people in the United States suffer from tinnitus, with 75 percent of patients over the age of 45. Of these, 2.5 million suffer from tinnitus, and as many as 10 to 12 million patients continue to seek medical attention for their tinnitus and desire treatment. The exact cause of tinnitus is not known. Exposure to noise is by far the most likely cause. 90% of people with tinnitus have varying degrees of noise-induced hearing loss.
In China, although there are no widely recognized epidemiological statistics, it is estimated that 120 million people suffer from tinnitus, accounting for 10% of the total population; 10% to 26% of adults have varying degrees of tinnitus, with 4% to 8% v. severe tinnitus.
It is generally believed that tinnitus becomes more severe with age, and a study in the UK pointed out that increasing age is a high risk factor for the incidence of tinnitus. In comparison, the incidence of tinnitus in people under 30 years of age was 1.3%, while over 61 years of age, the incidence increased to 8.5%. The relationship between gender and tinnitus is more interesting, generally speaking, the incidence of tinnitus is higher in younger women and older men.
Overall, men suffer from tinnitus in the range of 10-17%, while women suffer from 11-18%.
If we talk about the severity, women are higher than men.
Hearing impaired people suffer from tinnitus in 10% of cases, while those with normal hearing suffer from tinnitus less than those who are deaf.
The incidence of tinnitus in both ears exceeds that of tinnitus in one ear. Most of the patients with left ear tinnitus are male.
Common types of tinnitus
Tinnitus can be divided into two categories: subjective and objective.
Objective tinnitus, also known as other-perceived tinnitus. It is a type of tinnitus that can be heard by both yourself and others. It can be a rhythmic horseshoe sound, a pendulum sound or other rhythmless murmur. Other causes of tinnitus include: abnormal arteriovenous fistulas or aneurysms in the skull and neck that produce a pulsatile tinnitus consistent with a pulse; spasms of the soft palate and auditory tuberosities; and abnormal opening of the eustachian tube that prevents sound, which is often heard in tinnitus consistent with a respiratory rhythm.
Subjective tinnitus, also known as self-conscious tinnitus. Only the patient can feel the tinnitus, and it can be unilateral or bilateral. The nature of the tinnitus is varied and can be in the form of ringing, buzzing, whistling, air horn, insects, etc. There are various causes of subjective tinnitus, and the common etiologies include: inflammation of the external ear canal, cerumen foreign bodies, tumor obstruction; various types of middle ear pathologies such as middle ear classes, intra-drum lesions, otosclerosis; Meniere’s disease, ototoxic drug poisoning, degenerative changes of the inner ear in old age, inflammation, tumors, vascular abnormalities in the inner ear canal and skull; craniocerebral trauma, skull base fractures, etc.; some internal diseases such as anemia, hypertension, In addition, mental tension can cause changes in blood circulation and affect the blood supply to the inner ear, leading to tinnitus attacks, and tension can also make tinnitus worse.
Causes of Tinnitus
The causes of tinnitus are complex and can generally be divided into two main categories.
l Otogenic diseases (i.e. related to ear diseases). It is often accompanied by hearing loss, such as caused by ototoxic drug poisoning, viral infection, and insufficient blood supply to the inner ear.
l Non-otogenic diseases, these patients often have other symptoms of corresponding diseases besides tinnitus, such as cardiovascular disease, hypertension, diabetes, traumatic brain injury, etc.
We can summarize the causes of tinnitus into the following areas.
Ear diseases.
l Blockage of the external ear canal, whether it is cerumen, foreign body, tumor, fungal disease and inflammatory swelling, can lead to tinnitus. It is caused by the inability of the internal sound transmitted from the bone conduction to the middle ear to dissipate through the external auditory canal. The severity of tinnitus is consistent with the degree of blockage of the external auditory canal.
Only a small percentage of patients with middle ear inflammation have a mild degree of tinnitus.
l Negative pressure in the tympanic chamber, adhesions or fixation of the auditory chain can lead to tinnitus.
l Abnormal opening of the eustachian tube may result in objective tinnitus, with airflow through the eustachian tube rubbing and self-hearing enhancement during breathing.
l Tinnitus due to inner ear disorders is mostly high pitched. Tinnitus is particularly pronounced in otosclerosis, but is mostly low pitched.
l Sudden deafness is often accompanied by tinnitus.
l Tinnitus is also a precursor symptom for the onset of hearing loss in the elderly with degenerative changes in the sensorineural system.
l In Meniere’s disease, unilateral low-frequency wind-like tinnitus often precedes an attack of vertigo, but it can also occur at the same time as vertigo and deafness. After several attacks or a severe attack, the tinnitus is often permanent and high-frequency.
l The tinnitus in noisy hearing loss is mostly high-tone and persistent for a longer period of time.
Cardiovascular disease.
l Tinnitus is pulsatile, often in line with the heartbeat or pulse, and is often more intense, with about 10% of them being hypertensive.
In patients with anemia, tinnitus is also pulsatile due to increased cardiac output, and may sometimes be a persistent buzzing sound.
l Pulsatile objective tinnitus can be produced by abnormal blood vessels in the head and neck area or skull base, and vascular murmurs can be heard in the head and neck area such as the temporal area, external auditory canal and neck. In addition to tinnitus, it may be accompanied by vertigo, hearing loss, mental swelling and other symptoms.
Metabolic diseases.
l hyperthyroidism, which causes pulsatile tinnitus due to increased cardiac blood output.
l Hypothyroidism, due to increased extracellular fluid or increased endolymphatic pressure, may also cause tinnitus.
The incidence of tinnitus due to diabetes mellitus is very high.
The incidence of tinnitus is higher in patients with hyperlipidemia with vascular obstruction and sensorineural deafness than in the general population.
l Vitamin deficiency may also cause tinnitus.
Myogenic disorders.
l The tinnitus is not synchronized with the pulse, the rhythm is irregular, and the intermittent “click, click” sound, mostly 1 to 2 times per second with relatively low intensity, is objective tinnitus, but compression of the neck vessels or neck movement has no effect on the tinnitus.
l It is related to spasmodic contraction of the pharyngopalatine muscle, tympanic membrane tensor muscle, and stapedius muscle. The palatal muscle clonus is the most common.
It is not only felt by the patient, but also heard by the bystanders at the opening of the external ear canal.
Neurological disorders:: l
Tinnitus has a high incidence after cranial trauma and is often accompanied by sensorineural deafness with high frequency or full frequency drop.
Tinnitus may also occur in meningitis and multiple sclerosis.
Drug toxicity reactions.
l Drugs such as aspirin, aspirin complex, quinine, and aminoglycoside antibiotics can cause ototoxicity, and tinnitus can appear earlier than deafness.
When heavy metals such as mercury, lead and arsenic are applied, tinnitus is often the main symptom of poisoning.
Aniline can cause severe tinnitus.
Coffee can increase the severity of tinnitus. Tinnitus may be significantly reduced after stopping the use of coffee, cocoa, tea and cigarettes, and it is often aggravated by cannabis leaf.
Other.
l Autoimmune deafness disease, temporomandibular joint syndrome, syphilis, and allergies can cause tinnitus.
l Mood swings, anxiety, and nervousness can also trigger tinnitus.
l Increased heart rate in high fever can often lead to pulsatile tinnitus.
Common factors that aggravate tinnitus
Mental tension: When you are under long-term mental stress and highly stressful working or living environment, or when your body is in a relatively fatigued state, it may aggravate tinnitus symptoms.
Bad habits: Excessive or inappropriate drinking of alcohol, coffee and smoking may aggravate tinnitus symptoms.
Noise: Prolonged exposure to noise or bursts of sound can lead to tinnitus and hearing loss.
Diet: Consumption of excessive fat and high salt is not conducive to tinnitus protection, and overeating is not conducive to self-healing of the inner ear environment, which can somehow aggravate tinnitus.
Tinnitus mechanism
The mechanism of tinnitus is more complex and can occur in a variety of situations, which are summarized as follows.
Physiological tinnitus: Inside the body, faint sounds occur from blood vessel pulsation, blood flow, muscle contraction, joint activity, and respiratory movements, of which those closer to the ear will feel such sounds. Normally, this faint sound is not felt because there is a strong sound from outside, which masks the faint sound. However, if you walk into a sound isolation room or in the quiet late at night, you will sometimes feel a faint ringing sound in your ear, which is physiological tinnitus.
Conductive tinnitus: This kind of tinnitus is caused by disorders in the conductive part of the auditory system, such as swelling, blockage of the external auditory canal, perforation of the eardrum, entrapment, middle ear inflammation, adhesions, and sclerosis. The conduction disorder reduces the ability to hear external sounds and diminishes its role in masking the sounds occurring in the body so that they can be felt and become tinnitus. In addition, the sound that is transmitted into the ear through the bone conduction is blocked from escaping to the outside due to the conduction disorder, and the sound sensation in the ear is increased to become a low-frequency, wind-like whirring sound. We can try it ourselves by covering our ears with one hand and feel the booming sound in our ears, which is typical of conductive tinnitus.
Neurological tinnitus: The cause is a disorder in the sensor nerve part of the auditory system. Tinnitus occurs when the auditory receptors in the inner ear are diseased, such as drug poisoning, noise trauma, Meniere’s disease, etc.; when the auditory nerve and auditory center suffer trauma or inflammation, poisoning, ischemia, tumors, etc.; and when various intracranial lesions affect the auditory nerve or auditory center. This kind of tinnitus is mostly high-frequency cicada or piercing shrill sound. Some systemic diseases can also cause tinnitus, such as hypertension, hypotension, plant nerve dysfunction which affects blood supply, the influence of toxins from certain diseases, endocrine disorders caused by mental tension and anxiety, etc. Tinnitus can also occur after poor rest and insomnia in life. There are also some cases of deafness whose causes are not clear with the current medical technology or are not clear in clinical examination, which are called tinnitus of unknown origin.
In addition, recent studies have suggested that
Cochlear tinnitus: It is generally believed that the cochlea is the main lesion site of tinnitus, and about 90% of tinnitus is related to cochlear dysfunction. The mechanism of its formation is still inconclusive, and possible mechanisms include: due to the influence of various lesions or factors, such as impaired blood supply to the inner ear, lymphatic fluid circulation inside and outside the inner ear, and changes in ion concentration (e.g. intracellular calcium ions play a role in adjusting the balance of inward and outward currents in neurons and hair cells This may lead to abnormal spontaneous firing rhythms of cochlear neurons, mechanical dysfunction of the cochlea (e.g., impulsive noise, abnormal movement of ectolymph, increased direct current of hair cells, loss of coupling or abnormal coupling of hair cell static cilia to the capsule, disruption of electrical insulation between hair cells or nerve structures, spontaneous neural locking activity that is misperceived by the center as sound and tinnitus), dysfunction of outer hair cell oscillations (tinnitus is caused by a disorder of mechanical feedback to sound waves in the cochlea, and abnormal micromechanical activity (spontaneous oscillations) in the cochlea). There are many sympathetic nerve distributions in the cochlear hair cells (mechanism of action unknown), and sympathetic activity has a significant effect on the cochlea, including cochlear blood flow. Studies have shown that the temporary threshold of excitability of cochlear hair cells is reduced after sympathectomy when exposed to loud sounds, while blocking the sympathetic nerve into the ear or cervical sympathetic ganglion removal in some patients with Ménière’s disease can reduce tinnitus. This suggests that sympathetic nerves and their activity play a role in the mechanism of cochlear tinnitus.
Central tinnitus: In recent years, research on central tinnitus has received attention abroad. Many studies have shown that the central nervous system (cerebral cortex) is involved in the production and maintenance of tinnitus. For example, tinnitus can persist after complete recovery from cochlear lesions; after vagus destruction or auditory nerve severance, tinnitus persists or instead worsens in about 1/3 to 1/2 of patients. The use of corticosteroids and other immunosuppressive drugs for rapidly progressive autoimmune vestibular cochlear disease can protect hearing and vestibular function, but is not effective for tinnitus. This suggests that the site of such tinnitus may be in the nerve center. Whether the site of tinnitus production is peripheral or central, the reception, further processing and translation of tinnitus signals occur in the central area. Recent foreign studies using functional brain imaging techniques (positron emission tomography PET, single photon emission tomography SPECT, functional magnetic resonance imaging fMRI) have shown increased neural activity in the frontal middle gyrus, middle temporal gyrus, anterior cuneus, paracentral lobule, and lateral and posterior middle part of the right cerebral hemisphere in tinnitus patients, or increased local cerebral blood flow, which may suggest that the brain is responsible for This may suggest that the brain has a “tinnitus center” that is responsible for tinnitus.
The following views on the mechanism of central tinnitus exist.
l The central hypersensitivity theory
l plastic changes in the auditory center
l Neurobiological patterns
l Involvement of the proprioceptive system
l Diminished hypothalamic inhibition by amelogenic acid
Tinnitus diagnosis
Based on the patient’s complaints. The doctor can easily determine whether the patient has tinnitus or not, but the diagnosis of the etiology of tinnitus requires a series of tests, including routine otolaryngological examinations, audiological examinations, tinnitus tests, and sometimes even some necessary neurological and systemic diseases. Early diagnosis and treatment of tinnitus, like any other disease, can help improve the condition and recovery. For example, the ototoxicity of aminoglycoside antibiotics is often preceded by tinnitus, followed by hearing loss, so when tinnitus occurs, the drug should be stopped immediately; the appearance of tinnitus or the aggravation of tinnitus in patients with anemia or hypertension indicates further deterioration of the disease and should be alerted; if tinnitus occurs in long-term workers in a noisy environment, a change of working environment should be considered. In some cases, if the cause of tinnitus is clearly identified early, such as cerumen embolism and secretory otitis media, corresponding treatment measures can be taken and the tinnitus will disappear. However, in about 40% of patients, no obvious cause can be found for the tinnitus. Doctors call it idiopathic tinnitus.
Principles of Tinnitus Diagnosis
The diagnosis of tinnitus can be based on history, audiological findings and psychological assessment to determine the cause, localization, qualitative and quantitative analysis of tinnitus.
Determining the cause.
The determination of the cause or predisposing factors of tinnitus is of great importance for the diagnosis and treatment of tinnitus. According to our observation, more than 50% of central tinnitus is related to psychosomatic disorders such as plant nerve dysfunction, sleep disorders, mental tension and mood swings. Some special conditions related to tinnitus such as before menstruation, after consuming coffee and alcohol, and a certain special head position can guide the treatment.
Localization.
There is no precise method to locate tinnitus, but the localization method of deafness can be used to locate the site of tinnitus. It can be classified as conductive (lesions located in the outer or middle ear), sensorineural (inner ear), neurological, central, or mixed tinnitus, and Eyshold proposed a general localization diagnosis of tinnitus based on the results of the masking test and lidocaine test, with a valid masking test for inner ear tinnitus, a valid lidocaine test for neurological tinnitus, and both invalid for central tinnitus.
Qualitative.
That is, to determine the nature of the tinnitus, e.g.
Tone of tinnitus ① Low tone, middle tone, high tone. Middle and inner ear lesions often cause low and mid-tone tinnitus. Neurological and central tinnitus are often high pitched. Continuous tinnitus such as cicada sound is often subjective tinnitus, while pulsating tinnitus or tinnitus with rhythmic characteristics is often objective tinnitus. Musical sounds are often musicians’ specific tinnitus. (3) Monotone, polyphony, and variable tones. Polyphony is often indicative of multiple lesions or pathologic processes. Variable tinnitus is often indicative of cervical spondylosis.
Tinnitus and cranial tinnitus Bilateral tinnitus of the same frequency and the sensation of sound diffusion in the skull is called cranial tinnitus, suggesting that the site of tinnitus may be in the hearing center.
Tinnitus can be divided into acute (a2cute), subacute (subacute) and chronic (chronic) tinnitus according to the duration of the disease: tinnitus that occurs within 3 months is acute, those with a duration of 4 months to 1 year are subacute, and those with a duration of more than 1 year are chronic. ②Intermittent, persistent, paroxysmal tinnitus. Many normal people can develop transient transient tinnitus, suggesting transient inner ear vasospasm or auditory system dysfunction. Tinnitus in Ménière’s disease is associated with fluctuations in the condition.
It can be classified as compensatory or non-compensatory tinnitus depending on the presence or absence of secondary neuropsychiatric symptoms. If the tinnitus is mild, or if there is heavy tinnitus but the patient has gradually adapted to it, it is called compensatory tinnitus. If tinnitus causes disturbance in concentration and sleep, is accompanied by irritability, depression, anxiety and other symptoms, and affects work and social activities, then it is called non-compensatory tinnitus.
Quantification.
Physician’s assessment of tinnitus: frequency of tinnitus and loudness matching examination.
Subjective assessment by the patient: The tinnitus has a low, medium or high pitch. Depending on the severity of the tinnitus and the presence or absence of accompanying symptoms, the degree of tinnitus is classified as follows: Grade 0: no tinnitus; Grade 1: occasional tinnitus, but no pain; Grade 2: persistent tinnitus, noticeable in quiet; Grade 3: persistent tinnitus even in noisy environments; Grade 4: persistent tinnitus with concentration and sleep disturbances; Grade 5: persistent severe tinnitus that prevents the patient from working; Grade 6: suicidal tendency due to severe tinnitus Grade 6: Suicidal tendency due to severe tinnitus.
The purpose and steps of tinnitus diagnosis
Tinnitus is extremely difficult to diagnose because it is a symptom of many systemic and local diseases as well as an independent disease (idiopathic tinnitus), and is closely related to the patient’s psychological state. Therefore, the diagnosis of tinnitus should aim at
1. diagnosis of the lesion site.
2. diagnosis of the etiology.
3. diagnosis of the severity of the disease, so that the diagnosis can determine the treatment method and observation of the changes in the disease. In order to achieve the purpose of tinnitus diagnosis, the following steps must be followed.
(a) History taking
(ii) General clinical examination
(iii) Audiometric testing
(iv) Vestibular function examination
(v) Tinnitus testing
The diagnosis of tinnitus may also include a minimal comprehensive audiological evaluation as well as CT of the temporal bone and MRI of the head. Identification of sensorineural deafness requires examination with the aforementioned tests to differentiate between sensorineural and neural deafness. Pulsatile tinnitus requires an angiogram of the vascular system including the carotid and vertebral arteries to rule out arterial obstruction, aneurysms and vascular tumors.
Treatment of Tinnitus
Some tinnitus is often a concomitant symptom of a systemic disease, so the fundamental treatment of tinnitus is to identify the cause and treat the primary disease. In some cases, the cause of tinnitus cannot be found, and the aim of treatment is to reduce the loudness of tinnitus and to achieve tinnitus compensation.
If the tinnitus is still present after treatment of the primary disease, or if the primary disease cannot be found, the tinnitus needs to be analyzed and treated symptomatically. Symptomatic treatments include
I. Drug treatment: 1. Western drug treatment: The treatment plan for acute tinnitus is the same as that for sudden deafness. The treatment plan for acute tinnitus is the same as that for sudden deafness. Low and medium frequency tinnitus is treated with hormone + improvement of microcirculation; high frequency tinnitus is treated with calcium ion antagonist + hormone. Sub-acute and chronic tinnitus are commonly treated with vasodilators to improve microcirculation, and also hormone injection behind the ear (for low-frequency tinnitus); for lidocaine positive, vasodilators, carbamazepine, phenytoin sodium, vitamin B1 and adenosine B12 and other nerve-nourishing drugs should be used. 2. Chinese medicine treatment: divided into five types: spleen deficiency and loss of health, liver fire disturbance, kidney essence deficiency, phlegm fire stagnation and wind-heat invasion.
II. Psychological counseling and psychotherapy: Through verbal and non-verbal communication methods, we can influence and change the psychological state and psychological barriers of tinnitus patients, so as to interrupt the vicious circle and treat tinnitus. Psychological guidance (counseling): Solving confusion is an important part of the tinnitus treatment process.
3. Masking therapy: Tinnitus masking device is used to treat tinnitus by using external acoustic stimulation to inhibit the spontaneous excitation of the inner ear or the auditory nerve, and hearing aids can also be used instead of masking devices
4. Acoustic therapy: By increasing the environmental noise, the background sound environment of the tinnitus patient’s hearing is changed. Increasing the background sound of the tinnitus patient’s environment helps to weaken the patient’s nerve center’s ability to discriminate between the tinnitus sounds and thus diminish the perception of it. The fundamental principle of sound therapy is to allow the patient to avoid being in a quiet environment, which can be done by various means such as noise generators, radios, and music players.
V. Acupuncture: Buried ear beans, acupuncture, floating needles, etc.
VI. Surgical treatment: Surgical treatment of tinnitus has been limited because surgery itself can cause tinnitus.
1.Internal jugular vein ligation
2.Neurectomy
3.Microvascular decompression
4.Vascular interventional stenting
Hearing aid therapy: For tinnitus patients with hearing loss, hearing aid is the recommended treatment method. This is because for tinnitus patients with hearing loss, the environmental noise may not be enough for them to relieve their pain. Then wearing hearing aids can amplify the background noise and alleviate the pain of tinnitus, while also improving their ability to hear and communicate.
VIII. Combination therapy: It is popular at home and abroad to adopt multiple treatment programs to combine tinnitus treatment and achieve better effect than single therapy.
Tinnitus seven-combination therapy – a method recommended in China, which combines seven clinically common methods such as Chinese and Western medicine, psychotherapy, masking, sound therapy, surgery, acupuncture points and hearing aids, has achieved good results.