Pharynx, the pharynx, represents that part of the digestive tube and the airways, which is the connecting link between the cavity of the nose and mouth, on the one hand, and the esophagus and larynx, on the other. It extends from the base of the skull to the VI-VII cervical vertebrae. The inner space of the pharynx is the pharyngeal cavity, the cavitas pharyngis.
The pharynx is located behind the nasal and oral cavity and larynx, in front of the basilar part of the occipital bone and the upper cervical vertebrae. Accordingly, the organs located anterior to the pharynx, it can be divided into three parts: pars nasalis, pars oralis and pars laryngea.
- The upper wall of the pharynx, adjacent to the base of the skull, is called the vault, fornix pharyngis.
- Pars nasalis pharyngis, the nasal part, is functionally a purely respiratory department. Unlike the other parts of the pharynx, its walls do not collapse, since they are immovable.
- The front wall of the nasal department is occupied by the hoans.
- On the lateral walls is located on the funnel-shaped pharyngeal opening of the auditory tube (part of the middle ear), ostium pharyngeum tubae. Above and behind the opening of the tube is limited by a tubular roller, torus tubarius, which is obtained due to the protrusion of the cartilage of the auditory tube here.
[caption id="attachment_644" align="aligncenter" width="750"]
Anatomy of the Human Pharynx[/caption]On the boundary between the upper and the posterior walls of the pharynx, along the middle line is the accumulation of lymphoid tissue, tonsilla pharyngea s. adenoidea (hence - adenoids) (in an adult it is not noticeable). Another accumulation of lymphoid tissue, paired, is between the pharyngeal opening of the tube and the soft palate , tonsilla tubaria.
Thus, at the entrance to the pharynx there is an almost complete ring of lymphoid formations: the tongue almond, two palatine tonsils, two tubal and pharyngeal (lymphoepithelial ring described by NI Pirogov).
Pars oralis, the oral part, is the middle section of the pharynx, which in front is communicated through the pharynx, fauces, with the oral cavity; its posterior wall corresponds to the third cervical vertebra. According to the function, the oral part is mixed, since it crosses the digestive and respiratory tract. This cross was formed during the development of respiratory organs from the wall of the primary intestine. From the primary nosorotovoy bay formed nasal and oral cavity, with the nasal was located on top or as if dorsal to the oral, and the larynx, trachea and lungs originated from the ventral wall of the anterior gut. Therefore, the head of the digestive tract was found lying between the nasal cavity (from above and dorsally) and the respiratory tract (ventral), which is responsible for the intersection of the digestive and respiratory tract in the pharynx.
Pars laryngea, the guttural part, represents the lower section of the pharynx, located behind the larynx and extending from the entrance to the larynx to the entrance to the esophagus. On the front wall is the entrance to the larynx.
The basis of the pharyngeal wall is the fibrous membrane of the pharynx, fascia pharyngobasilaris, which is attached at the top to the bones of the base of the skull, is covered from the inside by the mucous membrane, and from the outside - by the muscular. The muscular membrane is in turn covered from the outside by a more thin layer of fibrous tissue that connects the pharyngeal wall with the surrounding organs, and at the top passes to m. buccinator and is called fascia buccopharyngea.
The mucous membrane of the nasal part of the pharynx is covered by the ciliated epithelium in accordance with the respiratory function of this part of the pharynx, in the lower sections of the epithelium the lamellar is flat. Here, the mucous membrane acquires a smooth surface, which helps slip the food lump when swallowed. This is also facilitated by the secret of the mucous glands embedded in it and the pharyngeal muscles located longitudinally (dilators) and circularly (narrowers).
[caption id="attachment_645" align="aligncenter" width="424"]
Anatomy of the Human Pharynx[/caption]The circular layer is much more pronounced and decomposes into three compressors arranged in 3 floors: the upper, m. constrictor pharyngis superior, medium, m. constrictor pharyngis medius and lower, m. constrictor pharyngis inferior.
Starting at various points: on the bones of the base of the skull (tuberculum pharyngeum of the occipital bone, processus pterygoideus wedge-shaped), on the lower jaw (linea mylohyoidea), on the root of the tongue, hyoid bone and cartilage of the larynx (thyroid and cricoid), the fibers of the muscles of each side go backwards and join together, forming a seam along the middle line of the pharynx, raphe pharyngis. The lower fibers of the lower throat compressors are closely related to the muscular fibers of the esophagus.
Longitudinal muscle fibers of the pharynx are part of two muscles:
- M. stylopharyngeus, a shillopharyngeal muscle, starts from the processus styloideus, is directed downward and terminates part of the wall of the pharynx, is partly attached to the upper edge of the thyroid cartilage.
- M. palatopharyngeus, palatine-pharyngeal muscle
[caption id="attachment_646" align="aligncenter" width="504"]
Anatomy of the Human Pharynx[/caption]Swallowing act. Since there is a cross in the pharynx of the respiratory and digestive tracts, there are special devices that separate the respiratory tract from the digestive tract during the act of swallowing. By contracting the muscles of the tongue, the food lump is pressed against the hard palate by the back of the tongue and is pushed through the pharynx. In this case, the soft palate is pulled upward (by contraction of mm. Levator veli palatini and tensor veli palatini) and approaches the posterior wall of the pharynx (contraction of m. Palatopharyngeus).
Thus, the nasal part of the pharynx (respiratory) is completely separated from the oral. Simultaneously, the muscles located above the hyoid bone, pull the larynx up, and the root of the tongue with the contraction m. hyoglossus goes down; he presses on the epiglottis, lowers the latter and thereby closes the entrance to the larynx (in the respiratory tract). Then there is a sequential contraction of the pharyngeal constrictors, as a result of which the food lump is pushed towards the esophagus. Longitudinal muscles of the pharynx function as lifters: they tighten the pharynx towards the food lump.
The pharynx nutrition occurs mainly from a. pharyngea ascendens and branches a. facialis and a. maxillaris of a. corotis externa. Venous blood flows into the plexus located above the muscular membrane of the pharynx, and then - along the vv. pharyngeae into the system v. jugularis interna. Outflow of lymph occurs in the nodi lymphatici cervicales profundi et retropharyngeales.
The pharynx is innervated from the nerve plexus - the plexus pharyngeus, formed by the branches nn. glossopharyngeus, vagus et tr. sympathicus. In this case, a sensible innervation is also performed with respect to n. glossopharyngeus and n. vagus; the throat muscles are innervated by n. vagus, with the exception of m. stylopharyngeus, which is supplied by n. glossopharyngeus.
To what doctors to address for examination of Pharynx:
- ENT
- Dentist
What diseases are associated with a pharynx:
- Laryngitis
- Acute tonsillitis (tonsillitis)
- Streptococcal pharyngitis
- Pharyngitis
- Chronic pharyngitis
- Chronic tonsillitis
- Angina in infectious diseases
- Sore throat tonsillitis (adenoiditis)
- Retropharyngeal (retropharyngeal) abscess
- Paratonzillite
- Parapharyngeal (peripharyngeal) abscess
- Hypertrophy of the nasopharyngeal tonsil (adenoids)
- Hypertrophy of palatine tonsils
- Foreign bodies of pharynx
- Wounds and injuries of the pharynx
What tests and diagnostics should be done for the pharynx:
Method of examination of the pharynx
Endoscopy of the pharynx