Cicatrical stenosis of the larynx and trachea
Causes of disease
The main reason for the acquired stenosis of the larynx are injuries, mainly of iatrogenic nature. They include traumatic investigations of the larynx and trachea, prolonged laryngeal intubation, multiple re-intubations, the use of intratracheal tubes which are of a larger diameter. In children, even the performance of conventional endotracheal intubation can lead to the development of stenosis in the sublaryngeal area due to its extremely small diameter. Other causes include external injuries and infections. We should also mention the so-called idiopathic stenosis, the cause of which cannot be established. In most of any cases cicatrical stenosis in the vocal folds arise as a result of previous surgical treatment in this area. The most common example is the numerous surgeries for papillomatosis of the larynx, which lead to the scarification in the area of the posterior commissure.
- The diameter of the respiratory tract. Subglottic area in children is the narrowest part of the larynx. Therefore, it is much easier to injure it. Moreover, it is the only area with a submucosal layer. It causes the rapid edema formation and further narrowing of the respiratory tract.
- Gastroesophageal reflux disease. Stomach and esophagus contents rise up, so it leads to irritation of the already injured mucous membrane and causes the inflammatory process.
- Pathogenesis — the mechanism of the disease Longstanding intratracheal tubes of the wrong size exerts pressure on the mucous membrane of the larynx and the initial section trachea. It leads to edema and inflammation. Next stage is mucosal ulceration, perichondritis and formation of scar tissue.
Pathogenesis — the mechanism of the disease
Longstanding intratracheal tubes of the wrong size exerts pressure on the mucous membrane of the larynx and the initial section trachea. It leads to edema and inflammation. Next stage is mucosal ulceration, perichondritis and formation of scar tissue.
The clinical picture varies considerably depending on the stenosis intensity, the age and person’s activity, as well as on his general physical condition. The main complaint is a respiratory difficulty. With stenosis at the level of the vocal folds, a person cannot inhale, whereas stenosis at the level of the subglottis or trachea leads to difficulty in inhaling and exhaling. Scarification at the level of the vocal folds in the area of the posterior commissure is presented more by hoarseness than by respiratory difficulty.
- General clinical examination is of utmost importance in idiopathic stenosis and should be directed to the diagnosis of sarcoidosis, Wegener’s granulomatosis and other autoimmune diseases. Endoscopic examination is the main in treatment planning. The first stage is fibrolaryngoscopy. It allows to determine the mobility of the vocal folds and the condition of the upper part of the larynx during normal breathing. Next, it is recommended to conduct the transnasal fibrolaryngoscopy in terms of drug induced sleep. It allows to determine the mobility of the vocal folds in people who cannot tolerate the procedure without anesthesia.
- Direct laryngoscopy under anesthesia is a diagnostic step of utmost importance for thorough planning of surgical treatment. It allows to determine the localization of stenosis, its degree and extent.
- X-ray diagnostics. Computed tomography plays an important role in determining the extent of total stenosis when it cannot be seen endoscopically.
- Balloon dilatation. It is a sparing treatment method in which the lumen of the subglottic area expands at the expense of a balloon, gradually filling with water. To use this method, many authors designate various indications, the main place among which, of course, is not the total closure of the respiratory tract lumen and the small extent of stenosis. In case of several unsatisfactory attempts of balloon dilation, it is recommended to proceed to surgical methods of treatment.
- Laryngotracheal reconstruction. During the surgery, the stenotic area of the subglottis or trachea is incised and allografts are established. Thus, a wider lumen of the respiratory tract is formed.
- Laryngotracheal exsection with anastomosis formation involves the complete dissection of the stenotic area of the respiratory tract.
In the postoperative period, in the vast majority of cases, it is necessary to install a T-shaped tube of precisely selected size from a special material. In a recent systematic review of the literature, the authors concluded that laryngotracheal exsection with anastomosis reduces the total number of operations performed in each patient and increases the number of decannullations.