Laryngeal malformations: causes, symptoms, diagnosis, treatment

Malformation of the larynx is rare. Some of them are completely incompatible with life, for example, with laryngotracheal pulmonary agenesis, atresia with complete obstruction of the larynx or trachea and bronchi. Other malformations are not so pronounced, but some of them can cause severe breathing disorders in the child immediately after birth, which require immediate surgical intervention to save his life. To such types of defects include the developmental defects of the epiglottis and its cysts, cysts of the anterior larynx and its diaphragm. The most frequent are the mild forms of vices that appear at different times after birth, most often when the child begins to lead an active lifestyle associated with the movement and development of the voice function. Sometimes, to these vices, the child adapts well enough, and they are found out by chance in years with a routine examination of the larynx. These defects include the cleavage of the epiglottis or vocal cords, incomplete laryngeal diaphragms, etc. Other defects of the larynx are found during their gradual development in postnatal ontogenesis (cysts, etc.) in connection with the emerging disturbances of certain functions of the larynx. Among the paralaringeal malformations, which can disrupt the functions of the larynx and cause its structural changes, it is worth noting the malformations of the thyroid gland, the laryngopharynx, etc.

Laryngoptosis. This defect is characterized by a lower location of the larynx than in the norm: the lower edge of the cricoid cartilage can be at the level of the sternum; described cases of laryngotosis, when the larynx was entirely located behind the sternum, when the upper edge of the thyroid cartilage was at the level of its handle. Laryngoptosis can be not only congenital, but also acquired defect, which develops either as a result of traction action of scars arising from lesions of the trachea and surrounding tissues, or in tumors pressing the larynx from above.

Functional disorders in congenital laryngotosis are manifested only by an unusual timbre of voice, which is assessed as an individual feature of the person, while the acquired forms cause atypical changes in the voice function, which are often accompanied by respiratory disturbances. When laryngoscopy of any structural endolaryngeal changes in the larynx in the usual laryngotosis is not detected.

Diagnosis of laryngotension does not cause difficulties, the diagnosis is easily established by palpation, in which the pomum Adami can be located in the area of the jugular notch, but in a typical place is not determined.

Treatment with congenital laryngotosis is not required, while in secondary laryngotosis, especially in combination with laryngeal obstruction, often requires a tracheotomy, which in such patients is often complicated by subcutaneous and mediastinal emphysema, pneumothorax, or stenosis of the lining space.

Defects of the development of thyroid cartilage - a very rare phenomenon. The most significant of them is the splitting of its ventral part, combined with a dystopy of the vocal folds (an increase in the distance between them and their location at different levels). More common is vice, in which there are no upper horns of the thyroid cartilage. In other cases, these formations can reach significant dimensions, reaching the hyoid bone, with which each of them can form an extra-laryngeal joint. There are also asymmetries in the development of the plates of the thyroid cartilage, which is accompanied by a change in the position and form of the vocal folds, the ventricles of the larynx, and other endolaryngeal malformations, which entail certain timbre features of the voice function. The respiratory function of the larynx does not suffer at the same time. There is no treatment for these defects.

The developmental defects of the epiglottis are observed more often than the defects noted above. They include the vices of form, volume and position. The most frequent defect is the cleavage of the epiglottis, which can occupy only its free part or spread to its base, dividing it into two halves.

Among the developmental defects of the epiglottis, changes in its shape are more common. Due to the structure of the elastic cartilage, the epiglottis in the infant of the first years of life is more flexible and soft than in adults, so that it can acquire a variety of forms, for example, with a folded front edge, which is sometimes observed in adults. However, most often there is an epiglottis in the form of a gutter with curved upward lateral margins, approaching along the middle line and narrowing the epiglottial space. In other cases, horseshoe-shaped or S-prominent epiglotti are observed, oblate in the anteroposterior direction.

Defects of development of intraarticular formations. These defects arise as a result of a disturbance in the resorption of the mesenchymal tissue that performs the laryngeal lumen in the first 2 months of embryonic development. With the delay or absence of resorption of this tissue, partial or total larynx atresia, circular cylindrical stenoses and, most often, guttural membranes - full or partial, located between the vocal folds and bearing the name of a laryngeal diaphragm - may occur.

The throat diaphragm is usually located in the anterior commissure and has the appearance of a crescent-shaped membrane, which contracts the edges of the vocal folds. The thickness of the laryngeal diaphragm varies, most often it is a whitish-grayish or grayish-reddish thin membrane that stretches out during inspiration and gathers into folds during phonation. These folds prevent the convergence of the vocal folds and give the voice a jarring character. Sometimes the laryngeal diaphragm is thick, and then the voice function is disturbed more significantly.

Diaphragms of the larynx can have different areas, occupying from 1/3 to 2/3 of the laryngeal lumen. Depending on the size of the diaphragm, respiratory failure of various degrees develops, up to asphyxia, which often occurs even with moderate stenoses against the background of colds of the larynx or its allergic edema. Small diaphragms of the larynx are found accidentally in adolescence or adulthood. Subtotal or total forms are detected immediately or in the first hours or days after birth as a result of the occurrence of respiratory disorders: in acute cases - the appearance of signs of asphyxia, with incomplete diaphragm - noisy breathing, sometimes cyanosis, a constant difficulty in feeding the baby.

Diagnosis in newborns is determined by signs of mechanical obstruction of the larynx and in direct laryngoscopy, during which the doctor should be ready for immediate perforation of the diaphragm or its removal. Therefore, direct laryngoscopy must be prepared as a microendolaringological surgical intervention.

Treatment for diaphragms of the larynx consists in dissection or excision of the membrane, followed by buoyage with a hollow buzhem to prevent stenosis of the larynx. With more severe congenital fibrosis stenoses after tracheotomy, the thyroid cartilage (thyrotomy) is dissected and, depending on the degree and location of the scar tissue, an appropriate plastic surgery is performed, analogous to those used in the acquired Rubs stenoses of the larynx. In adults, laryngostom is most often formed for more effective postoperative care of the larynx cavity, as often it is necessary to stop the appearing granulations, reposition of the cutaneous or mucosal plastic flap covering the wound surfaces, holding the toilet and treating the larynx with antiseptic agents. Plastic flaps are fixed to the underlying tissues using a dummy of elastic spongy material or an inflatable balloon, replaced daily. With a good engraftment of the flaps and the absence of granulation tissue, the laryngostomy is plasticly closed and the bulb dilator retained for 2-3 days, then it is removed with the aid of a thread attached to it, which is removed through the tracheostomy. Instead of an inflatable balloon, you can use the A. Ivanov tee.

In children, operative removal of the membrane is performed only with obvious signs of respiratory failure, which is an obstacle to normal physical development of the body and a risk factor for the occurrence of acute asphyxia in colds. In all other cases, surgical treatment is postponed until the larynx develops completely, that is, up to 20-22 years. With a full or subtotal laryngeal diaphragm, the life of a newborn can only be rescued by immediate perforation of the membrane, which can be performed by a laryngoscope with a diameter of 3 mm or, under appropriate conditions, a tracheotomy.

Congenital cysts of the larynx appear much less often than cysts acquired, arising during postnatal ontogenesis as a result of certain laryngeal diseases (retentional, lymphogenous, posttraumatic, etc.). Sometimes the congenital cysts of the larynx grow intensively during intrauterine development of the fetus and reach a considerable size, resulting in asphyxia and death immediately after the birth of the child. In other cases, these cysts develop more or less slowly, causing a breathing disorder or a swallowing disorder during feeding. The true cyst is a cavity whose walls include almost all layers of epidermoid formations: in its cavity there is a lining of multilayered planar epithelium with different degrees of keratosis, deflated epithelium and cholesterol crystals. Under the epidermis there is a connective tissue layer, and outside the cyst is covered with the mucous membrane of the larynx.

Most congenital cysts of the larynx are manifested by some signs of laryngeal function disorders between the 3rd and 15th months after birth. Among these disorders, the most characteristic is the laryngeal stridor. Respiratory disorders due to the congenital cuff of the larynx grow gradually, while the disorders resulting from the developmental defects of the epiglottis, as the ligamentous and cartilaginous apparatus consolidate, the strengthening of the inner-throat muscles gradually decrease.

Cysts arise, as a rule, in the area of the entrance to the larynx, from where they spread downwards, filling themselves with pear-shaped sinuses, ventricles of the larynx and intercostal space, penetrating the scaly folds. Often, congenital cysts are localized on the vocal fold.

A variety of the congenital cyst of the larynx is the so-called groove (a narrow notch on the surface of the vocal fold parallel to its free edge). This cyst is well detected only in stroboscopy, in which it is revealed during phonation by its rigidity and detached from the true voice fold.

The diagnosis is made with direct laryngoscopy, during which puncture of the cyst is possible, its opening, partial removal of its wall and, thus, prevention of asphyxia of the infant. With large cysts, her puncture is performed outside, through the skin, which prevents her infection.

[1], [2], [3], [4], [5], [6], [7]