The recurrent laryngeal nerve is a part of the X. Cranial Nerve. It is responsible for supplying the muscles of the larynx. Its very curved path in the brain is striking.
What is the laryngeal recurrent nerve?
The laryngeal recurrent nerve becomes the X. XII. Cranial Nerves. This is the vagus nerve. The laryngeal recurrent nerve, like all other cranial nerves, is part of the central nervous system and is located in the head. The vagus nerve is the only cranial nerve that innervates beyond the head and neck region of the human body. It divides into three areas in its supply function. These include the head area, the neck area as well as the chest area. In the area of the neck, the recurrent laryngeal nerve is formed. This consists of nerve fibers from the vagus nerve as well as the glossopharyngeal nerve. This is the IX cranial nerve, which is mainly responsible for processing taste stimuli. The recurrent laryngeal nerve is of particular medical interest because it has many bends in its course. This makes it very vulnerable to diseases such as the formation of metastases. Its main function is to supply the muscles of the larynx. The larynx is an important element in the swallowing process and voice production.
Anatomy and structure
The vagus nerve emerges from the medulla oblangata behind the olive. It then exits the cranial cavity through a small opening at the posterior base of the skull. This opening is called the zygomatic vein hole or foramen jugulare. Subsequently, the vagus nerve with its various branches moves into the thoracic part, the cervical part as well as the thoracic part of the human organism. The laryngeal recurrent nerve is part of the thoracic part of the vagus nerve. This descends in the vascular nerve cord of the neck with the internal carotid aorta and the internal jugular vein. Along this path, it gives off the ramus pharyngeus. This, together with the glossopharyngeal nerve, forms the pharyngeal plexus. The pharyngeal plexus innervates the pharynx. Two other branches depart from the plexus and travel to the larynx. These are the superior laryngeal nerve and the recurrent laryngeal nerve. The recurrent laryngeal nerve is the lower branch. It exits the vagus nerve at about the level of entry into the thorax. It then bends to the left below the aortic arch, and then bends upward to the right below the subclavian aorta. It continues to pass between the trachea and esophagus. It then makes its way upward to the larynx. There it passes below the vocal fold and innervates nearly all the muscles of the larynx.
Function and tasks
The main function of the recurrent laryngeal nerve is to supply the laryngeal muscles. It alone supplies all the laryngeal muscles. These are necessary to establish the functioning of the larynx. The larynx performs two important tasks. During swallowing, it closes the entrance to the trachea. In this way, it ensures that the ingested liquids or food enter the esophagus and not the trachea next to it. The entrance to the trachea is formed by the trachea. The larynx lifts the epiglottis when swallowing. It thus closes the entrance to the trachea and ensures that the path into the esophagus is paved. In addition, the larynx is responsible for the production of the voice. It is considered the actual voice generator. The laryngeal recurrent nerve supplies the mucous membrane of the larynx with its fibers. This is produced below the larynx. The mucosa is located in the glottis or subglottic space. The glottis is involved in processes in vocal fold vibration.
Diseases
The recurrent laryngeal nerve has an important function and clinical significance because of its course. It is often affected by lymph node metastases. These form in bronchial carcinoma. Since this often grows from the lung hilus into the mediastinum, the recurrent laryngeal nerve is very quickly affected. In addition, the nerve can easily become entrapped. Due to its bends, it is very susceptible to this. Once other structures in the brain shift due to various causes, the laryngeal recurrent nerve may become damaged. Shifts in the brain can be caused by brain swellings. These are triggered by tumor diseases, surgical interventions or accidents. Since the skull offers no possibility of evasion due to its solid structure, the tissue and various vessels shift into the smallest gaps in the brain.The laryngeal recurrent nerve is often pinched in the process due to its anatomy. The pinched laryngeal recurrent nerve causes a unilateral loss of function of the laryngeal muscles. This leads to hoarseness. At the same time, hoarseness is an initial symptom of life-threatening bronchial carcinoma or aortic aneurysm. The laryngeal recurrent nerve is often injured during surgical procedures in the thyroid area. It runs along the thyroid capsule and, if damaged, can also cause loss of function of the laryngeal muscles. If bilateral damage to the recurrent laryngeal nerve occurs, the result is bilateral vocal cord paralysis. This can lead to severe respiratory distress, resulting in a life-threatening condition. In this case, the glottis can no longer open wide enough, which triggers the shortness of breath. Inflammation of the nerves leads to failures or functional limitations of the larynx, thyroid gland as well as the vocal cords. Inflammation of nerves is called neuritis. Pain occurs in these regions. Causes of neuritis may include toxic influences, infection, or injury.
