In microtia, the outer ear develops abnormally, ranging from a tiny or misshapen ear to the complete absence of the ear. The causes, symptoms, diagnosis, treatment, and prevention of microtia will be discussed in this blog post. If the ear canal or middle ear are affected, microtia can also result in hearing loss.
Causes of Microtia
Microtia occurs during the first trimester of pregnancy, when the ear structures are forming. The following factors may increase the risk:
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Pregnancy and rubella.
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Pregnancy-related abnormalities in vitamin A levels.
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Accutane (isotretinoin) use during pregnancy.
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There are some hereditary conditions, such as Treacher Collins syndrome.
Symptoms of Microtia
A microtia is characterized by an abnormal or missing outer ear. There are four types of severity:
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Type 1: All parts of the ear are deformed, but the ear is smaller than normal.
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Type 2: Missing or abnormal parts of the ear, partially formed and small.
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Type 3: There are some rudimentary structures in the ear, but no recognizable components.
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Type 4: There is no ear at all (anotia).
The degree of the ear canal or middle ear malformation can affect the degree of hearing loss. People with microtia may also have difficulty locating the source of sound.
Diagnosis of Microtia
The doctor usually diagnoses microtia at birth through a physical examination of the ear and may also look for other birth defects that may be associated with microtia, such as cleft lip and palate, or facial asymmetry. A CT scan and hearing test may be ordered by the doctor to determine the inner ear structures and hearing function.
Treatment of Microtia
Microtia can be treated in many ways, depending on the individual needs and preferences of the patient and the family. The main goals are to improve the appearance of the ear and to restore hearing function.
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Prosthetic ears: These are artificial ears that attach to the head with adhesive or magnets. They can be made to match the shape, size, color, and shape of the natural ear.
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Surgery involving regenerating an ear using cartilage from the ribs or other sources is known as ear reconstruction surgery. The surgery is usually performed in stages, starting at the age of 6 or 7, when the cartilage in the ear has matured enough. The appearance and symmetry of the ear can be improved by ear reconstruction surgery, but hearing may not be improved.
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It is possible to improve the hearing ability of the affected ear with devices such as bone conduction devices and implantable devices. Bone conduction devices are worn behind the ear and transmit sound vibrations through the skull to the inner ear. In contrast, implantable devices are surgically implanted and stimulate the inner ear directly. A hearing device can be used alone or in conjunction with ear prosthetics or ear reconstruction surgery.
Prevention of Microtia
Since microtia's cause is often unknown, there is no sure way to prevent it. However, there are some general measures that may reduce the risk:
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By getting vaccinated before conception or avoiding contact with people who are infected, you can prevent rubella infection during pregnancy.
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Eating a balanced diet or taking supplements as prescribed by your doctor can help maintain adequate vitamin A levels during pregnancy.
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When pregnant or trying to conceive, do not use Accutane (isotretinoin) as it can cause serious birth defects.
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Genetic counseling should be sought if there is a family history of microtia.
