Currently, for visual examination of the larynx is widely used microlaringoscopy, a method of accurate recognition and differential diagnosis, as well as micro-laryngosurgical interventions for various diseases of the larynx. As the director of the otorhinolaryngological hospital of Marburg University im. Phillips (Germany) prof. Dr. O. Kleinsasser (O. Kleinsasser), this method has proven itself in the detection of malignant tumors of the larynx at an early stage. According to O. Kleinsasser, microlaringoscopy and microlaringosurgery presuppose that the performer has relevant knowledge and skills, as well as considerable practical experience for successful and safe use of them. These studies and operations are not carried out as easily as doctors often believe with insufficient experience and operator skills. Therefore, the number of irreversible damage to the larynx due to improper interventions is still quite large today.
Various laryngoscopes are used to perform the microlaringoscopy. So, the routine method of diagnosis is now the so-called loupe laryngoscopy, which uses a telelaringoscope with cylindrical lenses that provide not only excellent illumination of the larynx and the larynx, but also a slightly enlarged image.
More convenient for inspection of hard-to-reach areas of the larynx is the fiber optic rhinopharyngolaringoscope. This tool is recommended to be used, in particular, in disorders of the larynx. Special additional eyepieces on the operating microscope, especially when using the so-called sectional optics, allow a parallel observation of the operation and document its progress with a video camera or a camera equipped with an automatic exposure meter. Illumination of the larynx is carried out only by a halogen lamp ("cold" light) of an operating microscope or by means of a pulsed light fixture controlled by a microcomputer.
Indications for microlaryngoscopy
Indications for micro-laryngoscopy are doubtful cases in the diagnosis of premolars of the larynx and the need to take a biopsy, as well as for surgical removal of defects that violate the voice function. Mikrolaringoskopiya and especially direct laryngoscopy are contraindicated in patients with severe cardiac and circulatory disorders (bradyarrhythmia, post-infarction), in which each anesthesia is associated with increased risk. Mikrolaringoskopiya virtually impossible with significant pathological changes in the field of SHOP, not allowing contracture or trisme, preventing the opening of the mouth and the introduction of a laryngoscope into the larynx.
The use of micro-laryngoscopy requires the use of endotracheal anesthesia using a small intubation catheter. Jet IVL is indicated only in particularly cramped anatomical conditions.
The technique of conducting a micro-laryngoscopy provides for a number of stages, including the following positions.
Giving the patient the right position
O. Klensasser recommends the following method of laying the patient: the patient must lie on a horizontal table on the back; Do not use head-restraining head-restraints to prevent head movements, and the head should not hang. After intubation of the trachea and insertion of the protective lining for the teeth, tilt the head of the fully relaxed patient as far as possible in the dorsal direction. Only after making sure that the lips and tongue of the patient are not infringed, introducing a laryngoscope with a conical end forward, up to the glottis, following the intubation catheter. The intubation catheter should be located more dorsally than the laryngoscope, in the posterior commissure, when manipulated in the field of this commissure, it should be in the front commissure. The laryngoscope should be moved gently, avoiding lever movements. With the optimal laryngoscope installation, an unlimited view of the vocal folds from the anterior commissure to the vocal appendages of the arytenoid cartilages is provided. When installing a laryngoscope with a breast support, excessive pressure of the laryngoscope on the larynx should be avoided. To get a better view of her cavity, you should ask the assistant to press the larynx back. For a detailed examination of the lateral surface of the larynx, the same method can be used to shift it to the side.
With particularly difficult access, for example, long teeth, pronounced upper prognathia, stiff neck, laryngoscope is introduced into the larynx slightly obliquely from the corner of the mouth, turning the patient's head, tilted to the dorsal direction, to the left or to the right.
After fixing the laryngoscope in the desired position, remove the light guide and place the operating microscope in the working position. After sucking off mucus, examine the laryngeal cavity at different magnifications. Prior to the beginning of an operation, photodocumenting of the revealed pathological changes is made through an operating microscope.
The method of video microlaringoscopy has become more and more widespread in recent years as the most qualitative one in the diagnosis of various endolaryngeal diseases and microsurgery of the larynx. For the first time microsurgery of the larynx with the use of video microlaringoscopy was introduced into practice in 1989. The principle of this method is the use of a miniature video camera that allows you to visualize the endoscopic picture of the larynx from different angles of view on the monitor screen, guided by the "picture" enlarged form, which with known skills greatly facilitates ongoing manipulations and increases the efficiency of the operation. As Prof. J. Thomassia, one of the pioneers of microsurgery of the larynx, with video microlaringoscopy provides the best conditions for examining the front commissure of the larynx and its vestibular department, while creating opportunities for an excellent overview of this hollow organ, even in persons whose examination is difficult due to a number of insurmountable circumstances: a short neck, obesity, children's age, etc. In addition, with video microlaringoscopy, photo and video documentation of the endoscopic picture of the larynx and of the surgical intervention is possible, providing high-quality visual aids as teaching aids. Using the monitor screen during surgery allows you to guide the operation, which is extremely important for the training of young professionals.