Otosclerosis

Otosclerosis is a pathological change characterized by abnormal bone growth in the middle ear, which leads to a disruption of the auditory system. The main mechanism underlying this disease is the fixation of the stapes, one of the auditory ossicles, which prevents the normal transmission of sound vibrations from the eardrum to the inner ear. Clinically, otosclerosis is manifested by progressive hearing loss, most often in the form of conductive hearing loss, and may also be accompanied by dizziness and tinnitus. The disease most often begins to manifest itself at a young age (from 20 to 40 years) and in most cases affects women. However, there is still no unified theory in medicine regarding the etiopathogenesis of otosclerosis, which creates certain difficulties in its diagnosis and treatment.

History of the disease and interesting historical facts

Otosclerosis was first described in the 19th century, but the oldest references to hearing disorders can be found in texts from ancient times. In 1861, the famous German otologist Hermann von Helmholtz presented his theory about the role of the stapes in the conduction of sound waves, which subsequently prompted a more in-depth study of hearing pathology. At the end of the 19th century, the German surgeon Ludwig von Tröltsch introduced the term "otosclerosis", which became generally accepted. Throughout the 20th century, many studies have been conducted that cover the mechanisms of otosclerosis development, its genetics and clinical manifestations, but there are still many questions without definitive answers.

Epidemiology

According to various sources, the incidence of otosclerosis is approximately 0.3% to 0.6% in the general population. Studies show that otosclerosis is more common in women aged 20 to 40 years, although it also occurs in men. Approximately 50% cases of the disease have a familial predisposition, which suggests a possible genetic link. In some populations, the incidence can reach 10%. An important point is that the manifestations of otosclerosis can be inherited, but do not always manifest in the same generation, which complicates family and genetic studies.

Genetic predisposition to this disease

Research suggests that otosclerosis may have a genetic predisposition. The main genes involved are thought to be:

• autosomal dominant gene associated with chromosome 15 (OTSC1),
• genes responsible for collagen synthesis, such as COL1A1 and COL1A2.
• other genetic factors, including various mutations, mechanisms of inclusion and excision, and the influence of alternative splicing in determining bone strength.

These findings highlight the multicomponent nature of the disease, the interaction of various genetic factors, and opportunities for further research to identify specific mutations that contribute to the development of otosclerosis.

Risk factors for the development of this disease

Risk factors for otosclerosis can be divided into two main groups: physical and chemical. Physical factors include:

• increased frequency of ear infections;
• previous head injuries;
• impact of acoustic trauma;
• primary or secondary osteoporosis, leading to changes in bone structure.

Chemical risk factors include:

• exposure to fluoride;
• infectious agents such as osteogenic viruses;
• exposure to certain toxic substances during work, such as benzene and arsenic.

It is also worth noting that hereditary factors can have a significant impact on predisposition to the disease.

Diagnosis of this disease

Diagnosis of otosclerosis is based on history and clinical examination. The main symptoms include:

• progressive hearing loss, usually unilateral or bilateral;
• tinnitus (noise in the ears);
• dizziness;
• inflammatory processes in the middle ear.

To clarify the diagnosis, laboratory tests such as audiometry are performed, as well as radiological examinations such as CT or MRI, which help to identify structural changes in bone tissue. Other types of diagnostics are also used, including intrinsic time credit audiometry to assess sound conduction. Differential diagnosis should be made with other forms of hearing loss, such as sensorineural hearing loss or otitis media.

Treatment

Treatment for otosclerosis may vary depending on the stage of the disease and the degree of hearing loss. The main treatment areas include:

• conservative treatment aimed at reducing the progression of the disease;
• pharmacological treatment, including the use of vasodilators and corticosteroids;
• a surgical procedure, most often a stapedectomy, in which the fixed stapes is removed and replaced with a prosthesis;
• other treatments, such as hearing aids.

An important aspect of treatment is regular monitoring of the progress of the disease.

List of medications used to treat this disease

The following groups of drugs are used to treat otosclerosis:

• steroids (corticosteroids);
• vasodilators (eg, diphenhydramine);
• calcium and vitamin supplements (eg, vitamin D);
• hypolipidemic agents, if indicated.

It is important to remember that drug treatment is not aimed at eliminating the causes of the disease, but at slowing its progression and supporting hearing.

Disease monitoring

Monitoring of otosclerosis includes regular examinations by otolaryngologists, audiometric testing and assessment of hearing function. Control stages are carried out depending on the dynamics of disease progression. The prognosis for patients varies depending on the degree of fixation of the stapes and the presence of concomitant pathology. Complications may include chronic otitis media, hearing loss up to complete deafness and impact on quality of life.

Age-related features of the disease

Otosclerosis can manifest itself at any age, but is most often diagnosed in young people. In children, the disease can manifest itself gradually, with a slight hearing loss, which is important to consider for early diagnosis. In old age, otosclerosis can be combined with degenerative changes in the auditory system, complicating diagnosis and treatment.

Questions and Answers

• What are the main symptoms of otosclerosis? Otosclerosis is characterized by progressive hearing loss, tinnitus and possible dizziness.
• How is otosclerosis diagnosed? Diagnosis includes audiometry, radiographic examinations, physical examinations and differential diagnosis.
• How is otosclerosis treated? Treatment includes conservative measures, medications and surgical intervention in the form of stagedectomy.
• What factors may increase the risk of otosclerosis? Risk factors include genetic predisposition, ear infections, and certain toxic factors.
• What is the prognosis for the disease? The prognosis depends on the degree of fixation of the stapes and the presence of concomitant diseases, but timely treatment can significantly improve the quality of hearing.