Mixed hearing loss
Last reviewed: 07.06.2024
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Mixed hearing loss is a condition in which a person experiences both conductive and perceptual hearing loss at the same time. To better understand this condition, let's understand what conductive and perceptual hearing loss are:
- Conductivehearing loss: Conductive hearing loss is associated with problems in the transmission of sound waves from the outer ear through the outer ear canal, eardrum and middle ear (including the auditory ossicle) to the inner ear. This can be caused, for example, by ear wax blockage, inflammation of the middle ear, or damage to the eardrum. Conductive hearing loss can usually be eliminated or improved by medical or surgical methods.
- Perceptualhearing loss: Perceptual hearing loss is associated with problems in the perception of sound signals within the inner ear and the transmission of information to the brain. It can be caused by damage to the inner ear structures, including the sensory hairs and the auditory nerve. Perceptual hearing loss is most often associated with age or high noise levels, but can also be caused by genetic factors, infections, and other conditions.
Mixed hearing loss indicates that a person has both conductive and perceptual components of hearing loss at the same time. This means that the ear has complex problems both in transmitting sound waves and in perceiving and processing them within the brain. Treatment for mixed hearing loss may include medical, surgical and audiologic methods depending on the cause and degree of hearing loss. Treatment should be tailored to the individual characteristics and clinical presentation of each patient.
Causes of the mixed hearing loss
Mixed hearing loss can have different causes, and it is usually due to a combination of conductive and perceptual hearing loss. Here are some of the possible causes of mixed hearing loss:
- Chronic middle ear inflammation: Repeated middle ear infections can cause damage to the eardrum and middle ear, causing conductive hearing loss. If left untreated or recurrent, these infections can contribute to the development of mixed hearing loss.
- Auditory ossicles: Damage or abnormalities of the auditory ossicles in the middle ear can cause conductive hearing loss. This can be caused by trauma, inflammation, or other factors.
- Noise and toxins: Prolonged exposure of the ear to strong noises or toxins can cause both conductive and perceptual hearing loss. Occupational noises or using loud music without hearing protection can contribute to this problem.
- Genetic Factors: Some hereditary or genetic factors can make a person more susceptible to mixed hearing loss.
- Age: Hearing can deteriorate with age and this can cause perceptual hearing loss. Mixed hearing loss can occur with other hearing problems.
- Other conditions: Other conditions such as autoimmune diseases, certain infections, or trauma may also contribute to mixed hearing loss.
Symptoms of the mixed hearing loss
Mixed hearing loss is a condition in which a person experiences combined symptoms of sensorineural and conductive hearing loss. Symptoms of mixed hearing loss may include signs of both forms of hearing loss. The following are common symptoms of mixed hearing loss:
- Hearing impairment: The main symptom of mixed hearing loss is a reduced ability to hear sounds. This hearing loss can be moderate to severe and can affect both ears.
- Decreased hearing clarity: People with mixed hearing loss may experience decreased hearing clarity. This means that they may have difficulty distinguishing sounds, especially in noisy or dense listening environments.
- Weak speech comprehension: Understanding speech can be difficult, especially in situations where speech is fast or unclear.
- Tinnitus: Tinnitus is the perception of noises in the ears, which can be of various types such as noise, buzzing, whistling, etc. Tinnitus can accompany mixed hearing loss.
- Ear pain (not always): Some people with mixed hearing loss may experience pain or discomfort in the ears, especially if there is inflammation or other ear problems.
- Balance problems (not always): In rare cases, mixed hearing loss can cause balance problems because the ear plays a role in regulating balance.
Stages
Hearing loss (hypoacusis) can be of varying degrees and is categorized according to how much hearing is impaired. Commonly accepted degrees of hearing loss are:
- Mild hearing loss: In this case, the hearing loss is slight. The person may have difficulty hearing soft sounds or conversations in noisy environments.
- Moderate hearing loss: Moderate hearing loss is characterized by moderate hearing loss. The patient may have difficulty hearing conversations, even at normal volumes, and may require the use of hearing aids.
- Severe hearing loss: In severe hearing loss, the patient has severe difficulty understanding speech and communicating. Hearing aids or other hearing devices may be necessary to correct the impaired hearing.
Mixed hearing loss can include both anterior and posterior hearing loss, as well as hearing loss with varying degrees of hearing loss at different frequencies of the sound spectrum. Mixed hearing loss may combine different types of hearing loss, such as anterior hearing loss (conduction hearing loss) and posterior hearing loss (transfer hearing loss).
In order to accurately diagnose the degree and type of hearing loss and to determine treatment and corrective measures, an audiometric study should be performed by an audiologist or an otorhinolaryngologist. Depending on the results of the audiometry, hearing aids, rehabilitation measures or surgical treatment, if necessary, may be prescribed.
Mixed conductive and sensorineural hearing loss is a form of hearing loss that combines elements of both conductive and perceptual hearing loss. In this particular form of hearing loss, there are problems with both the transmission of sound waves from the outer ear to the inner ear (conductive hearing loss) and the perception and processing of sound signals within the inner ear and brain (neurosensory hearing loss).
In simple terms, this means that the patient may have problems both in the outer and middle ear structures (e.g. Eardrum, auditory ossicles) and within the inner ear and the auditory nerve. This can be caused by different factors or conditions that affect both parts of the auditory system.
Examples of causes of mixed conductive and sensorineural hearing loss include:
- Chronic middle ear inflammation: Middle ear inflammation can cause both conductive changes, such as damage to the eardrum, and perceptual changes, such as damage to the auditory nerve.
- Ear trauma: Ear trauma can affect both the outer and middle ear structures as well as internal structures such as the auditory nerve.
- Mixed ear disorders: Some people may have congenital abnormalities that affect different parts of the auditory system.
- Genetic factors: Certaingenetic disorders can affect both the external and internal structures of the ear.
- Audiologic problems: Certain conditions, such as noise trauma or long-term exposure to noise, can affect different parts of the auditory system.
Diagnostics of the mixed hearing loss
Diagnosing mixed hearing loss (when a person has a combination of different types of hearing loss, such as anterior and posterior hearing loss) involves several steps and methods. The basic steps in the diagnostic process include the following:
- Physical examination and history: The doctor will typically begin by gathering information about the patient's medical and family history, including information about the presence or absence of previously identified hearing problems and factors that could affect ear health.
- Objective Ear Exam: The doctor performs a physical examination of the ears and external ear canal using instruments such as an Oreoscope to evaluate the condition of the ears and look for signs of infections, inflammation or abnormalities.
- Audiometry: This is a key test to determine the degree and type of hearing loss. The patient is asked to listen to sounds of different frequencies and volumes through headphones or ear buds and then respond to them. This test determines at what frequencies and how much hearing loss there is.
- Impedanceometry: This test evaluates how the impedance (resistance) of the ear system changes as the pressure in the ear canal changes. It can help detect middle ear disorders such as congestion, posterior hearing loss, and other abnormalities.
- Computed tomography (CT) or magnetic resonance imaging (MRI): In some cases, more detailed educational studies may be needed to determine abnormalities of the inner ears or other structural problems.
- Specialist consultation: Depending on the results of the tests, the doctor may prescribe additional consultations with specialists such as an audiologist or an otorhinolaryngologist.
Differential diagnosis
The differential diagnosis of mixed hearing loss involves identifying and distinguishing this condition from other types of hearing loss. The following conditions and causes of hearing loss may be similar to mixed hearing loss and require differential diagnosis:
- Purely conductive hearing loss: This is a condition in which a problem with the transmission of sound waves from the outer ear to the inner ear and brain is caused by the outer or middle ear structures. Examples include inflammation of the middle ear, difficulty conducting auditory waves through the ear drum, blockage of the outer ear canal, and other problems. Ultrasound and audiometry can help in the differential diagnosis.
- Purely perceptual hearing loss: In this case, the problem is related to the internal structures of the ear rather than the transmission of sound waves. It may be caused by damage to the sensory hairs of the inner ear, disorders of the auditory nerve, or other internal causes. Examples are age-related hearing degeneration, noise trauma, inner ear infections, etc.
- Mixed hearing loss with a more pronounced conductive or perceptual component: In some cases, patients may have a combination of both forms of hearing loss, but one type may dominate. It is important to determine which component is more significant in order to choose the right treatment options.
- Sensorineural hearing loss: This condition is usually associated with damage to the auditory sensory hairs and the auditory nerve within the inner ear. It is more often a perceptual hearing loss, but can sometimes have a conductive component, especially in mixed hearing loss.
The differential diagnosis of mixed hearing loss and the selection of appropriate treatment requires audiologic testing, including audiometry, impedance testing, audiogram analysis and other hearing tests. The results of these tests will help determine the type of hearing loss and the causes, which in turn will help determine the best method of treatment or hearing correction.
Treatment of the mixed hearing loss
The treatment of mixed hearing loss depends on its type, severity, and the specific causes and characteristics of the case. Typically, treatment may include the following methods and interventions:
- Hearing aids: Hearing aids may be recommended to correct impaired hearing. They can help improve hearing by amplifying sounds and adapting to the individual needs of the patient.
- Surgery: In some cases, especially if the mixed hearing loss is associated with anatomical abnormalities of the ears or middle ear, surgical treatment may be necessary. An example would be surgical removal of the septum in the middle ear.
- Medication: If the mixed hearing loss is due to inflammation, infection or other medical problems, medication may be prescribed to treat the underlying condition. This may help improve hearing.
- Rehabilitation and Audiology Treatment: Audiologists can offer rehabilitation programs that include training to improve auditory processing and adaptation to hearing aids.
- Avoiding factors that impair hearing: It is important to avoid exposure to high-intensity noise and other factors that may impair hearing or worsen symptoms.
- Hearing and Speech Therapy: In some cases, especially in children, sessions with hearing and speech therapists may be prescribed to develop communication skills and adapt to auditory changes.
Treatment for mixed hearing loss should be individualized and the treatment plan will be tailored to the specific needs and characteristics of each patient. It is important to consult with an otolaryngologist or audiologist for a detailed diagnosis and development of an appropriate treatment plan.
Literature
Palchun, V. T. Otorhinolaryngology. National manual. Brief edition / Edited by V. V. Т. Palchun. - Moscow : GEOTAR-Media, 2012.