What are the parts of the human nose called? Clinical anatomy of the nose. External nose. Superior and middle turbinates

The main components of the respiratory organ include the external nose, nasal cavity and paranasal sinuses. These departments have their own anatomical features, which should be considered in more detail.

The structure of the outer part of the nose

The anatomy of the nose, more precisely, its outer part, is represented by a skeleton consisting of bones and cartilage. Joined together, they form a pyramid with three sides. The base of this pyramid faces downwards. Top part The outer part of the nose is in contact with the frontal bone, and is the root of the nose.

Going downwards, the nose forms a back, ending at an apex. The lateral surfaces in this part of the respiratory organ have a soft structure and are called the wings of the nose.

The wings of the nose have free edges that form the nostrils. They are separated by a movable segment of the nasal septum - the bridge of the nose.

The bones of the skeleton are placed in pairs and form the back of the nose. On the sides of the back are the frontal processes of the upper part of the jaw. Grouping with them, the cartilages of the nose form the nasal slopes and ridge, which, in turn, connecting with the nasal bone, form an opening in the skeleton, reminiscent of a pear in shape. It is the outer part of the human nose.

Features of cartilage tissue

The cartilage of the nose is firmly attached to its bones. They are formed from the upper (triangular) cartilages, arranged in pairs, and the lower (large) cartilages of the organ. The wings of the nose are made up of them.

The large cartilage consists of a medial and lateral crus. Between these cartilages - the lateral and major - there are small cartilaginous processes, which are also part of the wings of the nose.

Muscles and soft tissues

The external nose consists of soft tissues. Their structure, in turn, is formed from such components as the muscles of the nose, fat cells and epidermal covers. The structure and thickness of the skin and fat layer varies for each person depending on the individual characteristics of his body.

The nasal muscles cover the lateral and major cartilages, which help retract the alar bones and compress the nostrils. Muscle tissue is also attached to the crura of the alar cartilage, which helps lower the nasal septum and raise the upper lip.

Structure of the nasal cavity

The anatomy of the nose (its internal part) is more complex. The nasal cavity consists of 4 walls:

• side;
• internal;
• top;
• bottom.

The nasal cavity is divided by the bridge of the nose (nasal septum), which can sometimes be curved in one direction or the other. If the curvature is insignificant, it does not affect the functioning of the organ.

On the inside, the bridge of the nose is covered by the nasal mucosa. This is a very sensitive layer of epithelium that is easily subject to mechanical stress. If its integrity is violated, not only nosebleeds can occur, but also a bacterial infection.

Damage to the nasal mucosa can lead to the development of an inflammatory process - rhinitis. It is accompanied by copious secretion of clear mucus. When a bacterial or viral infection is attached, it may acquire a yellowish or greenish tint.

Three structures are directly involved in the formation of the nasal cavity:

• anterior third of the bony base of the skull;
• eye sockets;
• oral cavity.

The nasal cavity in front is limited by the nostrils and nasal passages, while in the back it smoothly passes into the upper part of the pharynx. The bridge of the nose divides the nasal cavity into two parts, which contribute to the uniform division of incoming air. Each of these components consists of 4 walls.

Inner nasal wall

The bridge of the nose plays a special role in the formation of the inner wall of the nose. Due to this, the wall is divided into 2 sections:

• posterosuperior, which consists of the plate of the ethmoid bone;
• posteroinferior, formed from the vomer.

Features of the outer wall

The outer wall is one of the most complex structures of the nose. It is formed by compounds:

• nasal bones;
• frontal process and medial surface of the bone of the upper jaw;
• the lacrimal bone, which is in contact with the back of the nasal wall;
• ethmoid bone.

The bony portion of the outer nasal wall is the place to which the 3 turbinates are attached. Due to the bottom, fornix and shells, a cavity is formed, which is called the common nasal passage.

The nasal turbinates are directly involved in the formation of three nasal passages - upper, middle and lower. The nasal cavity ends with the nasopharyngeal passage.

Features of the paranasal sinuses

The sinuses, located above and on the sides of the nose, also play a huge role in the functioning of the respiratory organ. They are closely interconnected with the nasal cavity. If they are damaged by bacteria or viruses, the pathological process also affects neighboring organs, so they also become involved in it.

The sinuses consist of a large number of various passages and openings. They are an excellent environment for the proliferation of pathogenic microflora. Due to this, the pathological processes occurring in the human body are significantly intensified, resulting in a worsening of the patient’s health.

Types of paranasal sinuses

There are several types of paranasal sinuses. Let's look at each briefly:

• Maxillary sinus , which is directly related to the roots of the backmost teeth (back quadruples, or wisdom teeth). If the rules of oral hygiene are not followed, an inflammatory process can begin not only in the gums and nerves of the tooth, but also in these sinuses.
• Frontal sinus - paired formations located deep in the bone tissue of the forehead. It is this part of the sinuses that is adjacent to the ethmoid labyrinth, which is subject to aggressive attacks by pathogenic microflora. Due to this arrangement, the frontal sinuses quickly intercept the inflammatory process.
• Lattice Maze - a formation with a large number of cells, between which there are thin partitions. It is located in close proximity to important organs, which explains its enormous clinical significance. With the development of a pathological process in this part of the sinuses, a person suffers intense pain, since the ethmoid labyrinth is located close to the nasociliary branch of the ophthalmic nerve.
• Main sinus , the lower wall of which is the vault of the human nasopharynx. When this sinus becomes infected, the health consequences can be extremely dangerous.
• Pterygopalatine fossa , through which quite a lot of nerve fibers pass. It is with their inflammation that most clinical signs of various neurological pathologies are associated.

As you can see, the organs that are closely connected with it are a complex anatomical structure. If there are diseases affecting the systems of this organ, their treatment must be approached extremely responsibly and seriously.

It is important to remember that this should only be done by a doctor. The patient’s task is to promptly detect alarming symptoms and contact a doctor, since if the disease is taken to a dangerous limit, the consequences can be catastrophic.

Useful video about the nasal cavity

The nose is an important part of the human body. It has a rather complex structure and performs many functions, ensuring free breathing and. From the point of view of clinical anatomy, the nose is usually divided into external and internal parts.

Structure of the external nose

The outside of the nose is covered with skin, which contains many sebaceous glands. This section of the nose consists of cartilage and bone tissue and is shaped like a triangular pyramid. Its upper part is usually called the root of the nose, which, lengthening, passes downwards into the back and ends at the apex. The wings of the nose are located on the sides of the back, they are movable structures and form the entrance to the nasal cavity.

The bony skeleton of the nose consists of thin and flat nasal bones; they are connected to each other (along the midline), as well as to other structures of the facial skeleton. Its cartilaginous part is represented by paired lateral cartilaginous plates located above and below.

This section of the nose is abundantly supplied with blood by the branches of the external carotid artery. The outflow of venous blood from this area has certain features, which is carried out into the anterior facial vein, which communicates with the ophthalmic vein and the cavernous sinus. This structure allows for the rapid spread of pathogens. infectious diseases with blood flow into the cranial cavity.

Inner part of the nose

The nasal cavity is located between the oral cavity, the orbits and the anterior cranial fossa. It communicates with the environment (through the nostrils) and the pharynx (through the choanae).

The lower wall of the nasal cavity is formed by the palatine bones and the processes of the same name of the upper jaw. In the depths of this wall, closer to the anterior, there is an incisive canal in which nerves and vessels pass.

The roof of the inner nose is formed by the following bone structures:

• cribriform plate of the same bone;
• nasal bones;
• anterior wall of the sphenoid sinus.

The olfactory senses penetrate here through the cribriform plate. nerve fibers and arteries.

The nasal septum divides the nasal cavity into two parts - cartilaginous and bone:

• The latter is represented by the vomer, the perpendicular plate of the ethmoid bone and the nasal ridge of the upper jaw.
• The cartilaginous part is formed by the own cartilage of the nasal septum, which has the shape of a quadrangle, which participates in the formation of the dorsum of the nose and is part of the movable part of the septum.

The lateral wall of the nasal cavity is the most complex. It is formed by several bones:

• lattice,
• palatal,
• wedge-shaped
• lacrimal bone,
• upper jaw.

It has special horizontal plates - the upper, middle and lower nasal concha, which conditionally divide the internal part of the nose into 3 nasal passages.

1. Inferior (located between the nasal concha and the bottom of the nasal cavity; the nasolacrimal canal opens here).
2. Middle (limited by two nasal conchas - inferior and middle; has anastomosis with all paranasal sinuses, except the sphenoid).
3. Superior (located between the vault of the nasal cavity and the superior nasal concha; the sphenoid sinus and the posterior cells of the ethmoid bone communicate with it).

In clinical practice, the common nasal passage is distinguished. It looks like a slit-like space between the septum and the nasal turbinates.

All parts of the inside of the nose, except the vestibule, are lined with mucous membrane. Depending on its structure and functional purpose, the respiratory and olfactory zones are distinguished in the nasal cavity. The latter is located above the lower edge of the middle turbinate. In this area of ​​the nose, the mucous membrane contains a large number of olfactory cells that can distinguish more than 200 odors.

The respiratory region of the nose is located below the olfactory region. Here the mucous membrane has a different structure; it is covered with multinucleated ciliated epithelium with many cilia, which in the anterior sections of the nose make oscillatory movements towards the vestibule, and in the posterior sections, on the contrary, towards the nasopharynx. In addition, this zone contains goblet cells that produce mucus and tubulo-alveolar glands that produce serous secretions.

The medial surface of the lower part of the middle turbinate has a thickened mucous membrane due to cavernous tissue, which contains a large number of venous dilations. This is precisely what is associated with its ability to quickly swell or contract under the influence of certain stimuli.

The blood supply to the intranasal structures is carried out by vessels from the carotid artery system, both from its external and internal branches. That is why, with massive ones, it is not enough to bandage one of them to stop it.

A feature of the blood supply to the nasal septum is the presence in its anterior part of a weak spot with thinned mucous membrane and a dense vascular network. This is the so-called Kisselbach zone. There is an increased risk of bleeding in this area.

The venous network of the nasal cavity forms several plexuses in it, it is very dense and has numerous anastomoses. The outflow of blood goes in several directions. This is due to high risk development of intracranial complications in diseases of the nose.

The nose is innervated by the olfactory and trigeminal nerves. The latter is associated with possible irradiation of pain from the nose along its branches (for example, into the lower jaw).

In addition, adequate functioning of the nose is necessary for normal blood gas exchange. Chronic diseases of the nose with or narrowing of the respiratory space lead to insufficient oxygen supply to the tissues and disruption of the nervous system.

Prolonged difficulty in nasal breathing in childhood contributes to delayed mental and physical development, as well as the development of deformation of the facial skeleton (changes in bite, high “Gothic” palate).

Let us dwell in more detail on the main functions of the human nose.

1. Respiratory (regulates the speed and volume of air entering the lungs; due to the presence of reflexogenic zones in the nasal cavity, it provides broad connections with various organs and systems).
2. Protective (warms and moisturizes the inhaled air; the constant flickering of the cilia cleanses it, and the bactericidal effect of lysozyme helps prevent pathogens from entering the body).
3. Olfactory (the ability to distinguish odors protects the body from the harmful influences of the environment).
4. Resonator (together with other air cavities, it participates in the formation of the individual timbre of the voice and ensures clear pronunciation of some consonant sounds).
5. Participation in lacrimal drainage.

Conclusion

Changes in the structure of the nose (developmental anomalies, curvature of the nasal septum, etc.) inevitably lead to disruption of its normal functioning and the development of various pathological conditions.

CLINICAL ANATOMY OF THE NOSE AND PARONASAL SINUSES

The upper respiratory tract includes nose, paranasal sinuses, pharynx and larynx.

Nose (nasus) is the initial part of the respiratory apparatus, in which the peripheral section of the olfactory analyzer is located. In clinical anatomy, the nose (or nasal cavity) is usually divided into external and internal.

2.1.1. Clinical anatomy of the external nose

External nose (nasus externus) It is represented by an osteochondral skeleton and has the shape of a triangular pyramid, with the base facing downwards (Fig. 2.1). The upper part of the external nose, bordering the frontal bone, is called root of the nose (radix nasi). From below the nose goes into bridge of the nose (dorsum nasi) and ends apex of the nose (apex nasi). The lateral surfaces of the nose in the apex area are mobile and form wings of the nose (alae nasi), their free edge forms the entrance to the nose or nostrils (nares), separated from each other by a movable part of the nasal septum (septum mobilis nasi).

The bony part of the skeleton consists of paired flat nasal bones (ossa nasalia), constituting the dorsum of the nose, adjacent to the nasal bones laterally on both sides frontal processes of the maxilla(processus frontalis maxillae), forming together with the cartilaginous part

Rice. 2.1. External nose: a – frontal projection; b – lateral projection; c – vestibule of the nasal cavity: 1 – nasal bones; 2 – frontal processes of the upper jaw; 3 – lateral cartilages of the nose; 4 – large wing cartilage; 5 – medial leg; 6 – lateral leg; 7 – cartilage of the nasal septum

external nose slopes and nasal ridge. These bones, together with the anterior nasal spine in the anterior section, make up pear-shaped aperture (hole) (apertura piriformis) facial skeleton.

The cartilaginous part of the external nose is firmly fused to the bones of the nose and has paired superior lateral cartilage - cartilago nasi lateralis(triangular cartilages) – and paired lower lateral cartilages (large wing cartilages) (cartilago alaris major). The large wing cartilage has medial and lateral legs (crus mediale and laterale). Between the lateral and large cartilages of the wings of the nose there are usually unstable small cartilages of the wings of different sizes - cartilagines alares minores(sesamoid cartilages).

The skin of the external nose contains many sebaceous glands, especially in the lower third. Bending over the edge of the entrance to the nasal cavity (nostrils), the skin lines the walls of the nasal vestibule for 4-5 mm (vestibulum nasi). Here it is equipped with a large amount of hair, which creates the possibility of pustular inflammation, boils, and sycosis.

The muscles of the external nose in humans are rudimentary and large. practical significance Dont Have. They play a role in widening and narrowing the entrance to the nasal cavity.

Blood supply. The external nose, like all soft tissues of the face, has abundant blood supply(Fig. 2.2), mainly from the external carotid artery system:

- angular artery (a. angularis)- from the anterior facial artery (a. faciales anterior).

- dorsal artery of the nose (a. dorsalis nasi), which is the terminal branch of the ophthalmic artery (a. ophthalmica),- from the internal carotid artery system.

Connecting with each other in the area of ​​the root of the external nose, the angular artery and the artery of the dorsum of the nose form an anastomosis between the systems of the internal and external carotid arteries.

Rice. 2.2. Blood supply to the external nose:

1 – angular artery; 2 – facial artery; 3 – dorsal artery of the nose

Rice. 2.3. Veins of the external nose: 1 – facial vein; 2 – angular vein; 3 – superior ophthalmic vein; 4 – cavernous sinus; 5 – internal jugular vein; 6 – pterygoid plexus

Veins of the external nose(Fig. 2.3). The outflow of blood from the soft tissues of the external nose is carried out into the facial vein (v. facialis), which is formed from the angular vein (v. angularis), external nasal veins (vv. nasales externae), superior and inferior labial veins (vv. labiales superior et inferior) and deep vein of the face (v. faciei profunda). Then the facial vein flows into the internal jugular vein (v. jugularis interna).

Clinically important is the fact that the angular vein also communicates with the superior ophthalmic vein (v. ophthalmica superior), which drains into the cavernous sinus (sinus cavernosus). This makes it possible for the infection to spread from inflammatory foci of the external nose to the cavernous sinus and the development of severe orbital and intracranial complications.

Lymphatic drainage from the external nose it is carried out to the submandibular and parotid lymph nodes.

Innervation external nose:

Motor – carried out by the facial nerve (n. faciales);

Sensitive – I and P branches of the trigeminal nerve (n. trigeminus)- supra- and infraorbital nerves – nn. supraorbitalis et infraorbitalis).

2.1.2. Clinical anatomy of the nasal cavity

Nasal cavity (cavum nasi) located between the oral cavity (bottom), anterior cranial fossa (top) and orbits (lateral

But). It is divided by the nasal septum into two identical halves; in front, through the nostrils, it communicates with external environment, posteriorly through the choanae - with the nasopharynx. Each half of the nose is surrounded by four paranasal sinuses - the maxillary (maxillary), ethmoid, frontal and sphenoid (Fig. 2.4).

Rice. 2.4. Paranasal sinuses: a – frontal projection: 1 – frontal; 2 – maxillary; 3 – cells of the lattice labyrinth;

b – side view: 1 – sphenoid sinus; 2 – superior nasal concha; 3 – middle turbinate; 4 – inferior nasal concha

The nasal cavity has four walls: lower, upper, medial and lateral (Fig. 2.5).

Bottom wall(bottom of the nasal cavity) is formed anteriorly by two palatine processes of the upper jaw and posteriorly by two horizontal plates of the palatine bone. Along the midline, these bones are connected by a suture. Deviations in this connection lead to various defects (cleft palate, cleft lip). In the anterior section, the bottom of the nasal cavity has an incisive canal (canalis incisivus), through which the nasopalatine nerve (n. nosopalatinus) and nasopalatine artery (a. nosopalatina). This must be kept in mind during submucosal resection of the nasal septum and other operations in this area in order to avoid significant bleeding. In newborns, the bottom of the nasal cavity comes into contact with the tooth germs, which are located in the body of the upper jaw.

Rice. 2.5. Walls of the nasal cavity:

1 – top; 2 – lateral; 3 – medial; 4 – lower

The upper wall of the nasal cavity, or roof (vault), in the anterior section it is formed by the nasal bones, in the middle sections - by the ethmoidal (perforated, sieve-shaped) plate of the ethmoid bone (lamina cribrosa ossis ethmoidalis), in the posterior section - the anterior wall of the sphenoid sinus. The perforated plate of the ethmoid bone in the vault has a large number of holes (25-30), through which the filaments of the olfactory nerve, the anterior ethmoid artery and the vein connecting the nasal cavity with the anterior cranial fossa pass into the nasal cavity. A newborn has a cribriform plate (lamina cribrosa) It is a fibrous plate that ossifies by the age of three.

medial wall, or nasal septum (septum nasi), consists of anterior cartilaginous and posterior bone sections (Fig. 2.6). The cartilaginous section is formed by the cartilage of the nasal septum - cartilago septi nasi (quadrangular cartilage), the upper edge of which forms the anterior section of the dorsum of the nose, and the anteroinferior section participates in the formation of the movable part of the nasal septum (pars mobilis septi nasi). The bone section is formed in the posterosuperior region and in the middle section perpendicular plate of the ethmoid bone (lamina perpendicularis), and in the posteroinferior - an independent bone of the nasal septum - vomer.

Rice. 2.6. Medial wall of the nasal cavity:

1 – nasal septum; 2 – movable part of the nasal septum; 3 – perpendicular plate of the ethmoid bone; 4 – opener

In a newborn, perpendicular plasticity of the ethmoid bone is represented by a membranous formation. Between the perpendicular plate and the vomer, between the cartilage of the nasal septum and the vomer, a strip of cartilage remains - growth zone. Damage to the growth plate in children (for example, during surgery) can cause deformation of the septum and external nose. Complete formation and ossification of the nasal septum ends by the age of 10; further growth of the septum occurs due to growth zones.

In the area of ​​the growth zones, due to the different rates of development of cartilage and bone tissue, spikes and ridges of the nasal septum can form, causing disruption of nasal breathing.

Lateral(lateral, external) nasal wall- the most complex in its structure, formed by several bones. In the anterior and middle sections it is formed frontal process of the maxilla, medial wall of the maxilla, lacrimal bone, ethmoid cells. In the posterior sections, the following are involved in its formation: perpendicular plate of the palatine bone and medial plate of the pterygoid process of the sphenoid bone, which form the edges of the choanae. Joana limited medially to posterior

by the edge of the vomer, laterally by the medial plate of the pterygoid process of the sphenoid bone, above by the body of this bone, below by the posterior edge of the horizontal plate of the palatine bone.

Three nasal conchae are located on the lateral wall in the form of horizontal plates. (conchae nasales): lower, middle and upper (conchae nasalis inferior, media et superior). The inferior turbinate, the largest in size, is an independent bone; the middle and superior turbinates are formed by the ethmoid bone.

All nasal conchae, attached to the lateral wall of the nasal cavity in the form of elongated flattened formations, form under them, respectively lower, middle and upper nasal passages. Between the nasal septum and the nasal turbinates, a free space in the form of a gap is also formed; it extends from the bottom of the nasal cavity to the vault and is called common nasal passage.

In children, there is a relative narrowness of all nasal passages, the inferior concha descends to the bottom of the nasal cavity, which causes quickly onset difficulty in nasal breathing even with slight swelling of the mucous membrane during catarrhal inflammation. The latter circumstance entails a violation of breastfeeding, since without nasal breathing the child cannot suck. In addition, in young children the short and wide auditory tube is located horizontally. Under such conditions, even with minor inflammation in the nasal cavity, nasal breathing becomes significantly more difficult, which creates the possibility of infected mucus from the nasopharynx being thrown through the auditory tube into the middle ear and causing acute inflammation of the middle ear.

Lower nasal passage (meatus nasi inferior) located between the inferior turbinate and the floor of the nasal cavity. In the area of ​​its arch, at a distance of about 1 cm from the anterior end of the shell, there is outlet of the nasolacrimal duct (ductus nasolacrimalis). It forms after birth; a delay in its opening interferes with the outflow of tears, which leads to cystic dilatation of the duct and narrowing of the nasal passages. The lateral wall of the lower nasal passage in the lower sections is thick (has a spongy structure), closer to the place of attachment of the inferior nasal concha it becomes significantly thinner, and therefore it is easiest to puncture the maxillary sinus in this place, making an indentation of approximately 1.5 cm from the anterior end of the shell.

Middle nasal passage (meatus nasi medius) located between the inferior and middle nasal turbinates. The lateral wall in this area has a complex structure and is represented not only by bone tissue, but also by a duplicate of the mucous membrane, which is called "fontanella"(fontanelles). On the lateral wall of the middle nasal passage, under the nasal concha, there is a semilunar (crescent-shaped) fissure (hiatus semilunaris), which in the rear part forms a small expansion in the form funnels (infundibulum ethmoidale)(Fig. 2.7). The outlet opens into the lattice funnel anteriorly and upward frontal sinus canal, and behind and downwards - natural anastomosis of the maxillary sinus. The semilunar fissure opens anterior and middle cells of the ethmoidal labyrinth. The natural anastomosis of the maxillary sinus in the infundibulum is covered uncinate process – processus uncinatus(small crescent-shaped plate of the ethmoid bone), delimiting the semilunar fissure in front, so the outlet openings of the sinuses, as a rule, cannot be seen during rhinoscopy.

On the side wall of the nasal cavity in the region of the anterior end of the middle turbinate, one or a group of air cells can sometimes be identified - the nasal ridge (agger nasi) in the form of small protrusions of the mucous membrane, bordering below the surface of the uncinate process.

A common structural variant is the pneumatized anterior end of the middle turbinate - bulla (concha bullosa ethmoidale), which is one of the air cells of the ethmoid labyrinth. The presence of a bubble (bulla) of the middle turbinate can lead to impaired aeration of the paranasal sinuses with subsequent inflammation.

IN last years in connection with the active introduction of endoscopic methods surgical intervention it is necessary to know the details of the anatomical structure and the main “identifying” anatomical formations of the nasal cavity. First of all, the concept "ostiomeatal complex" is a system of anatomical formations in the area of ​​the anterior section of the middle turbinate. It consists of uncinate process(crescent bone plate), which is the medial wall of the infundibulum (infundibu- lum). Anterior to the uncinate process, at the level of attachment of the upper end of the middle turbinate, are located cells of the nasal ridge (agger nasi). The latter can be represented by a single

Rice. 2.7. Structure of the lateral wall of the nasal cavity:

a – bone skeleton of the lateral wall of the nasal cavity after removal of soft tissues: 1 – frontal process of the maxilla; 2 – nasal bone; 3 – superior nasal concha; 4 – middle turbinate; 5 – inferior nasal concha; 6 – perpendicular plate of the palatine bone;

7 – internal plate of the pterygoid process of the sphenoid bone;

8 – lacrimal bone; 9 – sphenopalatine foramen; 10 – horizontal plate of the palatine bone; b – lateral wall of the nasal cavity after removal of the turbinates: 1 – cleft semilunaris; 2 – lattice funnel; 3 – outlet opening of the frontal sinus canal; 4 – outlet openings of the sphenoid sinus and posterior cells of the ethmoidal labyrinth; 5 – superior nasal concha; 6 – middle turbinate; 7 – inferior nasal concha; 8 – nasal roller; 9 – anterior nasal valve; 10 – outlet openings of the maxillary sinus and anterior cells of the ethmoidal labyrinth

cavity, but more often it is a system of individual cells that open into a lattice funnel. Posterior to the uncinate process, under the anterior end of the middle turbinate, you can see a large cell of the anterior group of the ethmoid sinuses - large ethmoidal vesicle (bulla ethmoidalis). Finally, the opposite portion of the nasal septum is also included in the concept of “ostiomeatal complex” (Fig. 2.8).

Rice. 2.8. Ostiomeatal complex (endoscopy picture): 1 – uncinate process; 2 – cells of the nasal ridge; 3 – large lattice vesicle; 4 – nasal septum; 5 – base of the middle turbinate; 6 – anterior section of the middle turbinate; 7 – common nasal passage

Upper nasal passage (meatus nasi superior) extends from the middle turbinate to the vault of the nose. At the level of the posterior end of the superior concha in the superior nasal meatus there is a wedge-ethmoid recess (sphenoethmoidal space), where the sphenoid sinus opens with an opening ostium sphenoidale and posterior cells of the ethmoidal labyrinth.

The nasal cavity and paranasal sinuses are lined with mucous membrane. An exception is the vestibule of the nasal cavity, which is covered with skin containing hair and sebaceous glands. The mucous membrane of the nasal cavity does not have a submucosa, which is absent in the respiratory tract (with the exception of the subvocal

cavities). Depending on the structural features of the mucous membrane and functional purpose, the nasal cavity is divided into two sections: respiratory (respiratory) and olfactory.

Respiratory region of the nose (regio respiratoria) occupies the space from the bottom of the nasal cavity to the level of the lower edge of the middle turbinate. In this area the mucous membrane is covered multirow columnar ciliated epithelium(Fig. 2.9). On the apical surface of the ciliated cells there are about 200 thin cilia 3-5 µm long, forming an almost continuous carpet. Ciliated microvilli make a directed movement backwards towards the nasopharynx, and in the very anterior section - towards the vestibule. The frequency of cilia vibrations is about 6-8 per second. The mucous membrane also contains multiple goblet cells that secrete mucus, and tubular-alveolar branched glands that produce serous or serous-mucosal secretion, which through the excretory ducts exits to the surface of the mucous membrane of the nasal cavity. Ciliated microvilli are immersed in the secretion of the tubular-alveolar glands, the pH is normally in the range of 7.35-7.45. Shifts in the pH of nasal mucus to the alkaline or acidic side slow down the vibrations of the cilia until they completely stop and disappear from the surface of the cells. After normalization of pH, depending on the degree of damage, restoration of cilia and clearance of the nasal mucosa occurs. Long-term infusion of any medications into the nose disrupts the function of the ciliated epithelium, which must be kept in mind when treating nasal diseases. Throughout its entire length, the mucous membrane is tightly fused with the perichondrium and periosteum, so it is separated during the operation along with them.

Rice. 2.9. Micrograph of ciliated epithelium (x 2600)

On the medial surface of the inferior turbinate and in the anterior parts of the middle turbinate, the mucous membrane of the nasal cavity thickens due to cavernous (cavernous) tissue, consisting of venous vascular expansions, the walls of which are richly supplied with smooth muscles. When exposed to certain irritants (cold air, muscle stress, etc.), the mucous membrane containing cavernous tissue can instantly swell or contract, thereby narrowing or expanding the lumen of the nasal passages, exerting a regulating effect on respiratory function. Normally, both halves of the nose usually breathe unevenly during the day - first one or the other half of the nose breathes better, as if giving the other half a rest.

In children, cavernous tissue reaches full development by the age of 6 years. At a younger age, in the mucous membrane of the nasal septum, sometimes there is a rudiment of the olfactory organ - the vomeronasal organ (Jacobson), located at a distance of 2.5-3 cm from the anterior edge of the nasal septum, where cysts can form and inflammatory processes occur.

Olfactory region (regio olfactoria) located in the upper parts of the nasal cavity - from the lower edge of the middle turbinate to the vault of the nasal cavity. The space between the medial surface of the middle turbinate and the opposite portion of the nasal septum is called olfactory fissure. The epithelial cover of the mucous membrane in this area consists of olfactory bipolar cells, represented by fusiform, basal and supporting cells. In places there are ciliated epithelial cells that perform a cleansing function. Olfactory cells are a peripheral nerve receptor, have a long filamentous shape with a thickening in the middle, which contains a round nucleus. Thin filaments extend from the olfactory cells - about 20 (filae olfactoriae), which through the cribriform plate of the ethmoid bone enter olfactory bulb (bulbus olfactorius), and then into the olfactory tract (tr. olfactorius)(Fig. 2.10). The surface of the olfactory epithelium is covered with a specific secretion produced by special tubular-alveolar glands (Bowman's glands), which promotes the perception of olfactory stimulation. This secretion, being a universal solvent, absorbs odorous substances (odorivectors) from the inhaled air, dissolves them and forms complexes,

Rice. 2.10. Olfactory region of the nasal cavity:

1 – olfactory filaments; 2 – cribriform plate of the ethmoid bone; 3 – olfactory tract

which penetrate the olfactory cells and form a signal (electrical) transmitted to the olfactory zone of the brain. More than 200 natural and artificial odors can be distinguished by the human olfactory analyzer.

BLOOD SUPPLY TO THE NASAL CAVITY

Most major artery nasal cavity - sphenopalatine (a. sphenopalatine) branch of the maxillary artery from the external carotid artery system (Fig. 2.11). Passing through the sphenopalatine foramen (foramen sphenopalatina) near the posterior end of the inferior turbinate, it provides blood supply to the posterior sections of the nasal cavity and paranasal sinuses. From it into the nasal cavity extend:

posterior nasal lateral arteries (aa. nasales posteriores laterales);

septal arteries (a. nasalis septi).

The anterosuperior parts of the nasal cavity and the area of ​​the ethmoid labyrinth are supplied with blood ophthalmic artery (a. ophthalmica) from the internal carotid artery system. From it through the cribriform plate into the nasal cavity extend:

anterior ethmoidal artery (a. ethmoidalis anterior); posterior ethmoidal artery (a. ethmoidalis posterior).

Rice. 2.11. Blood supply to the nasal cavity:

1 – sphenopalatine artery; 2 – ethmoidal arteries

A feature of the vascularization of the nasal septum is the formation of a dense vascular network in the mucous membrane in its anterior third - Kisselbach's place (locus Kisselbachii). Here the mucous membrane is often thinned. In this place, more often than in other parts of the nasal septum, nosebleeds occur, which is why it got the name bleeding area of ​​the nose.

Venous vessels. A feature of the venous outflow from the nasal cavity is its connection with the veins of the pterygoid plexus (plexus pterigoideus) and beyond the cavernous sinus (sinus cavernosus), located in the anterior cranial fossa. This creates the possibility of infection spreading along these routes and the occurrence of rhinogenic and orbital intracranial complications.

Lymph drainage. From the anterior sections of the nose it is carried out to the submandibular, from the middle and posterior sections to the retropharyngeal and deep cervical lymph nodes. The occurrence of sore throat after surgery in the nasal cavity can be explained by the involvement of the deep cervical lymph nodes in the inflammatory process, which leads to stagnation of lymph in the tonsils. In addition, the lymphatic vessels of the nasal cavity communicate with the subdural and subarachnoid space. This explains the possibility of meningitis occurring during surgical interventions in the nasal cavity.

In the nasal cavity there are innervation:

Olfactory;

Sensitive;

Vegetative.

Olfactory innervation is carried out by the olfactory nerve (n. olphactorius). Olfactory filaments extending from the sensory cells of the olfactory area (I neuron) penetrate into the cranial cavity through the cribriform plate, where they form the olfactory bulb (bulbus olphactorius). Here begins the second neuron, the axons of which go as part of the olfactory tract and pass through the parahippocampal gyrus (gyrusparahippocampalis) and ends in the hippocampal cortex (hipocampus), being the cortical center of smell.

Sensitive innervation of the nasal cavity occurs first (the ophthalmic nerve is n. ophthalmicus) and the second (maxillary nerve - n. maxillaris) branches of the trigeminal nerve. The anterior and posterior ethmoidal nerves depart from the first branch, which penetrate the nasal cavity along with the vessels and innervate the lateral sections and vault of the nasal cavity. The second branch participates in the innervation of the nose directly and through an anastomosis with the pterygopalatine ganglion, from which the posterior nasal branches extend (mainly to the nasal septum). The infraorbital nerve departs from the second branch of the trigeminal nerve to the mucous membrane of the bottom of the nasal cavity and the maxillary sinus. The branches of the trigeminal nerve anastomose with each other, which explains the irradiation of pain from the nose and paranasal sinuses to the teeth, eyes, dura mater (pain in the forehead, back of the head), etc. Sympathetic and parasympathetic (vegetative) innervation of the nose and paranasal sinuses is represented by the nerve of the pterygoid canal (vidian nerve), which originates from the plexus on the internal carotid artery (superior cervical sympathetic ganglion) and from the geniculate ganglion of the facial nerve.

2.1.3. Clinical anatomy of the paranasal sinuses

To the paranasal sinuses (sinus paranasalis) include air cavities surrounding the nasal cavity and communicating with it through openings. There are four pairs of air sinuses:

Maxillary;

Ethmoid sinuses;

Wedge-shaped.

In clinical practice, the paranasal sinuses are divided into front(maxillary, frontal, anterior and middle ethmoid sinuses) and rear(sphenoid and posterior sinuses of the ethmoid bone). This division is convenient because the pathology of the anterior sinuses is somewhat different from that of the posterior sinuses. In particular, communication with the nasal cavity of the anterior sinuses is carried out through the middle, and the posterior ones - through the upper nasal passage, which is important in diagnostic terms. Diseases of the posterior sinuses (especially the sphenoid) are much less common than the anterior ones.

Maxillary sinuses (sinus maxillaris)- paired, located in the body of the upper jaw, the largest, the volume of each of them is on average 10.5-17.7 cm 3. The inner surface of the sinuses is covered with a mucous membrane about 0.1 mm thick, the latter being represented by multirow columnar ciliated epithelium. The ciliated epithelium functions in such a way that the movement of mucus is directed in a circle upward to the medial corner of the sinus, where the anastomosis with the middle meatus of the nasal cavity is located. The maxillary sinus is divided into anterior, posterior, superior, inferior and medial walls.

Medial (nasal) wall sinus from a clinical point of view is the most important. It corresponds to most of the lower and middle nasal passages. It is represented by a bone plate, which, gradually thinning, in the area of ​​the middle nasal passage can turn into a duplication of the mucous membrane. In the anterior section of the middle nasal meatus, in the semilunar fissure, a duplicate of the mucous membrane forms a funnel (infundibulum), at the bottom of which there is a hole (ostium maxillare), connecting the sinus to the nasal cavity.

In the upper part of the medial wall of the maxillary sinus there is an excretory anastomosis - ostium maxillare, therefore, outflow from it is difficult. Sometimes, when examined with endoscopes, an additional outlet of the maxillary sinus is discovered in the posterior parts of the semilunar fissure. (foramen accesorius), through which the polypically altered mucous membrane from the sinus can protrude into the nasopharynx, forming a choanal polyp.

Front, or front, wall extends from the lower edge of the orbit to the alveolar process of the upper jaw and is most dense in the maxillary sinus, covered with soft tissues of the cheek and accessible to palpation. Flat bone depression

on the anterior surface of the facial wall is called canine, or canine, fossa (fossa canina), which is the thinnest part of the front wall. Its depth may vary, but on average it is 4-7 mm. With a pronounced canine fossa, the anterior and upper walls of the maxillary sinus are in close proximity to the medial one. This must be taken into account when performing sinus puncture, because in such cases the puncture needle can penetrate the soft tissue of the cheek or the orbit, which sometimes leads to purulent complications. At the upper edge of the canine fossa there is an infraorbital foramen through which the infraorbital nerve exits (n. infraorbitalis).

Upper, or orbital wall, is the thinnest, especially in the posterior region, where there are often digiscences. The canal of the infraorbital nerve runs through its thickness; sometimes there is a direct contact of the nerve and blood vessels with the mucous membrane lining the upper wall of the maxillary sinus. This should be taken into account when scraping the mucous membrane during surgery. The posterior superior (medial) sections of the sinus directly border the group of posterior cells of the ethmoid labyrinth and the sphenoid sinus, and therefore it is convenient to surgically approach them through the maxillary sinus. The presence of a venous plexus connected to the orbit by the cavernous sinus of the dura mater can contribute to the transition of the process to these areas and the development of serious complications, such as thrombosis of the cavernous (cavernous) sinus, orbital phlegmon.

Back wall sinuses thick, corresponds to the tubercle of the upper jaw (tuber maxillae) and yours back surface facing the pterygopalatine fossa, where the maxillary nerve, pterygopalatine ganglion, maxillary artery, and pterygopalatine venous plexus are located.

Bottom wall or the bottom of the sinus, is the alveolar process of the maxilla. The bottom of the maxillary sinus, with its average size, lies approximately at the level of the bottom of the nasal cavity, but is often located below the latter. With an increase in the volume of the maxillary sinus and a lowering of its bottom towards the alveolar process, protrusion of the roots of the teeth into the sinus is often observed, which is determined radiologically or during surgery on the maxillary sinus. This anatomical feature increases the possibility of developing odontogenic sinusitis (Fig. 2.12). Sometimes on the walls

Rice. 2.12. Anatomical relationship of the maxillary sinus and tooth roots

The maxillary sinus has bony ridges and bridges that divide the sinus into bays and very rarely into separate cavities. Both sinuses often have different sizes.

Ethmoid sinuses (sinus ethmoidalis)- consist of individual communicating cells separated from each other by thin bone plates. The number, volume and location of lattice cells are subject to significant variations, but on average there are 8-10 on each side. The ethmoid labyrinth is a single ethmoid bone that borders the frontal (superior), sphenoid (posterior) and maxillary (lateral) sinuses. The cells of the ethmoidal labyrinth laterally border the paper plate of the orbit. A common variant of the location of the ethmoid cells is their extension into the orbit in the anterior or posterior sections. In this case, they border on the anterior cranial fossa, while the cribriform plate (lamina cribrosa) lies below the roof of the cells of the ethmoid labyrinth. Therefore, when opening them, you must strictly adhere to the lateral direction so as not to penetrate into the cranial cavity through cribriform plate (lam. cribrosa). The medial wall of the ethmoidal labyrinth is also the lateral wall of the nasal cavity above the inferior turbinate.

Depending on the location, the anterior, middle and posterior cells of the ethmoidal labyrinth are distinguished, with the anterior and middle ones opening into the middle nasal passage, and the posterior ones into the upper nasal passage. The optic nerve passes close to the ethmoid sinuses.

Anatomo – topographic features ethmoidal labyrinth can contribute to the transition of pathological processes to the orbit, cranial cavity, and the optic nerve.

Frontal sinuses (sinus frontalis)- paired, located in the scales of the frontal bone. Their configuration and size are variable, on average the volume of each is 4.7 cm 3; on a sagittal section of the skull, its triangular shape can be noted. The sinus has 4 walls. The lower (orbital) for the most part is the upper wall of the orbit and for a short distance borders the cells of the ethmoid labyrinth and the nasal cavity. The anterior (facial) wall is the thickest (up to 5-8 mm). The posterior (brain) wall borders the anterior cranial fossa; it is thin, but very strong, and consists of compact bone. The medial wall (septum of the frontal sinuses) in the lower section is usually located in the midline, and upward it can deviate to the sides. The front and rear walls in the upper section converge at an acute angle. On the lower wall of the sinus, anterior to the septum, there is an opening of the frontal sinus canal, through which the sinus communicates with the nasal cavity. The canal may be about 10-15 mm long and 1-4 mm wide. It ends in the anterior part of the semilunar fissure in the middle meatus. Sometimes the sinuses extend laterally, may have bays and septa, be large (more than 10 cm 3), and in some cases are absent, which is important to keep in mind in clinical diagnosis.

Sphenoid sinuses (sinus sphenoidalis)- paired, located in the body of the sphenoid bone. The size of the sinuses is very variable (3-4 cm3). Each sinus has 4 walls. The intersinus septum divides the sinuses into two separate cavities, each of which has its own outlet leading into the common nasal passage (sphenoethmoidal recess). This location of the sinus anastomosis promotes the outflow of secretions from it into the nasopharynx. The lower wall of the sinus partly forms the roof of the nasopharynx, and partly the roof of the nasal cavity. This wall usually consists of spongy tissue and is of considerable thickness. The upper wall is represented by the lower

the surface of the sella turcica; the pituitary gland and part of the frontal lobe of the brain with the olfactory convolutions are adjacent to this wall on top. The posterior wall is the thickest and passes into the basilar part of the occipital bone. The lateral wall is most often thin (1-2 mm), bordered by the internal carotid artery and cavernous sinus, where the oculomotor, first branch of the trigeminal, trochlear and abducens nerves pass.

Blood supply. The paranasal sinuses, like the nasal cavity, are supplied with blood from the maxillary (a branch of the external carotid artery) and the ophthalmic (a branch of the internal carotid) arteries. The maxillary artery provides nutrition mainly to the maxillary sinus. The frontal sinus is supplied with blood from the maxillary and ophthalmic arteries, the sphenoid - from the pterygopalatine artery and from the branches of the meningeal arteries. The cells of the ethmoidal labyrinth are fed from the ethmoidal and lacrimal arteries.

Venous system The sinuses are characterized by the presence of a wide-loop network, especially developed in the area of ​​natural anastomoses. The outflow of venous blood occurs through the veins of the nasal cavity, but the branches of the sinus veins have anastomoses with the veins of the orbit and cranial cavity.

Lymphatic drainage from the paranasal sinuses is carried out mainly through the lymphatic system of the nasal cavity and is directed to the submandibular and deep cervical lymph nodes.

Innervation paranasal sinuses is carried out by the first and second branches of the trigeminal nerve and from the pterygopalatine ganglion. From the first branch - the ophthalmic nerve - (n. ophthalmicus) originate from the anterior and posterior ethmoidal arteries - n. ethmoidales anterior posterior, innervating the upper floors of the nasal cavity and SNP. From the second branch (n. maxillaris) branches depart n. sphenopalatinus And n. infraorbitalis, innervating the middle and lower floors of the nasal cavity and the SNP.

2.2. CLINICAL PHYSIOLOGY OF THE NOSE AND PARANASAL SINUSES

The nose performs the following physiological functions: respiratory, olfactory, protective and resonator(speech).

Respiratory function. This function is the main function of the nose. Normally, all inhaled and exhaled air passes through the nose. During inhalation due to negative

pressure in the chest cavity, air rushes into both halves of the nose. The main air flow is directed from bottom to top in an arched manner along the common nasal passage along the middle nasal concha, turns posteriorly and downward, and goes towards the choanae. When you inhale, part of the air leaves the paranasal sinuses, which helps to warm and humidify the inhaled air, as well as its partial diffusion into the olfactory area. When you exhale, the bulk of the air goes at the level of the inferior turbinate, some of the air enters the paranasal sinuses. The arcuate path, complex terrain and narrowness of the intranasal passages create significant resistance to the passage of the air stream, which has physiological significance - the pressure of the air stream on the nasal mucosa is involved in the excitation of the respiratory reflex. If you breathe through your mouth, your inhalation becomes shallower, which reduces the amount of oxygen entering your body. At the same time, the negative pressure from the chest also decreases, which, in turn, leads to a decrease in the respiratory excursion of the lungs and subsequent hypoxia of the body, and this causes the development of a number of pathological processes in the nervous, vascular, hematopoietic and other systems, especially in children .

Protective function. Inhaled air passes through the nose cleanses, warms and moisturizes.

Warming air is carried out due to the irritating effect of cold air, causing reflex expansion and filling of cavernous vascular spaces with blood. The volume of the shells increases significantly, and the width of the nasal passages narrows accordingly. Under these conditions, the air in the nasal cavity passes through a thinner stream and comes into contact with a larger surface of the mucous membrane, causing warming to occur more intensely. The warming effect is more pronounced the lower the outside temperature.

Hydration air in the nasal cavity occurs due to the secretion secreted reflexively by the mucous glands, goblet cells, lymph and tear fluid. In an adult, about 300 ml of water is released from the nasal cavities in the form of steam during the day, but this volume depends on the humidity and temperature of the outside air, the condition of the nose, as well as other factors.

Cleansing air in the nose is provided by several mechanisms. Large dust particles are mechanically retained in pre-

doors and nose thick hair. The finer dust that passed through the first filter, along with microbes, is deposited on the mucous membrane, covered with mucous secretion. The mucus contains lysozyme, lactoferrin, and immunoglobulins, which have a bactericidal effect. The deposition of dust is facilitated by the narrowness and curvature of the nasal passages. About 40-60% of dust particles and microbes of inhaled air are retained in the nasal mucus and are neutralized by the mucus itself or removed along with it. The self-cleaning mechanism of the respiratory tract, called mucociliary transport (mucociliary clearance), carried out by ciliated epithelium. The surface of the ciliated cells is covered with numerous cilia that perform oscillatory movements. Each ciliated cell has on its surface 50-200 cilia with a length of 5-8 microns and a diameter of 0.15-0.3 microns. Each cilium has its own motor device - an axoneme. The beating frequency of the cilia is 6-8 strokes per second. The motor activity of the cilia of the ciliated epithelium ensures the movement of nasal secretions and dust particles and microorganisms settled on it towards the nasopharynx. Foreign particles, bacteria, chemicals that enter the nasal cavity with the flow of inhaled air stick to the mucus, are destroyed by enzymes and are swallowed. Only in the most anterior parts of the nasal cavity, at the anterior ends of the inferior turbinates, the flow of mucus is directed towards the entrance to the nose. Total time the passage of mucus from the anterior parts of the nasal cavity to the nasopharynx is 10-20 minutes. The movement of cilia is influenced various factors– inflammatory, temperature, exposure to various chemicals, changes in pH, contact between opposing surfaces of the ciliated epithelium, etc.

When treating nasal diseases, it must be taken into account that any infusion of vasoconstrictor or other drops into the nose for a long time (more than 2 weeks), along with the therapeutic effect, has a negative effect on the function of the ciliated epithelium.

Defense mechanisms also include the sneezing reflex and mucus secretion. Foreign bodies, dust particles, entering the nasal cavity, cause a sneezing reflex: air suddenly with a certain

it is forcefully expelled from the nose, thereby removing irritating substances.

Olfactory function. The olfactory analyzer belongs to the organs of the chemical sense, the adequate irritant of which is molecules of odorous substances (odorivectors). Odorous substances reach the olfactory region along with the air when inhaled through the nose. Olfactory region (regio olfactorius) starts from the olfactory fissure (rima olfactorius), which is located between the lower edge of the middle turbinate and the nasal septum, goes up to the roof of the nasal cavity, has a width of 3-4 mm. For odor perception, air must diffuse into the olfactory region. This is achieved by short forced breaths through the nose, which creates a large number of turbulences directed towards the olfactory zone (this is the kind of inhalation a person takes when sniffing).

There are various theories of smell.

Chemical theory (Zwaardemaker). Molecules of odorous substances (odorivectors) are adsorbed by the liquid covering the hairs of the olfactory cells and, coming into contact with the cilia of these cells, dissolve in the lipid substance. The resulting excitation spreads along a chain of neurons to the cortical nucleus of the olfactory analyzer.

Physical theory (Heynix). Different groups of olfactory cells are excited in response to a certain frequency of vibrations characteristic of a particular odorivector.

Physico-chemical theory (Muller). According to this theory, stimulation of the olfactory organ occurs due to the electrochemical energy of odorous substances.

In the animal world there are anosmatics (dolphins), microsmatics (humans) and macrosmatics (rodents, ungulates, etc.). The sense of smell in animals is much more developed than in humans. For example, in a dog it is 10,000 times stronger, which is due to the close connection of vital functions with the sense of smell.

Impaired sense of smell may be primary when it is associated with damage to receptor cells, pathways or central parts of the olfactory analyzer, and secondary- if there is a violation of the air flow to the olfactory area.

The sense of smell decreases sharply (hyposmia) and sometimes disappears (anosmia) with inflammatory processes, polypous changes in the mucous membrane, atrophic processes in the nasal cavity.

In addition, a perverted sense of smell - cocosmia - is rare. The paranasal sinuses play mainly resonator And protective functions.

Resonator function the nose and paranasal sinuses is that they, being air cavities, along with the pharynx, larynx and oral cavity, participate in the formation of individual timbre and other characteristics of the voice. Small cavities (ethmoidal cells, sphenoid sinuses) resonate higher tones, while large cavities (maxillary and frontal sinuses) resonate lower tones. Since the size of the sinus cavity does not normally change in an adult, the timbre of the voice remains constant throughout life. Slight changes in voice timbre occur during sinus inflammation due to thickening of the mucous membrane. The position of the soft palate regulates resonance to a certain extent, separating the nasopharynx, and therefore the nasal cavity, from the middle part of the pharynx and larynx, where the sound comes from. Paralysis or absence of the soft palate is accompanied by an open nasal voice (rhinolalia aperta), obstruction of the nasopharynx, choanae, and nasal cavity accompanied by a closed nasal tone (rhinolalia clausa).

The nose is the initial part of the respiratory tract where air enters. God not only adorned our face with it, but also endowed it with a vital function for all organs and systems. The structure of the human nose is quite complex. In this article we will look at what the human nose consists of.

The nose is a part of a person’s face located below the bridge of the nose, in the lower region of which there are nostrils that perform respiratory and olfactory functions (see photo).

Diagram of the structure of the human nose:

Structure of the outer part of the nose

The structure of the external nose is represented by:

• partition;
• back;
• wings;
• tip.

In a newborn baby, it consists entirely of cartilage. By the age of three, the nose is partially strengthened by bone, like that of an adult. At the age of 14 years, several cartilages occupy 1/5 of its part.

The nostrils are lined with short hairs and trap fine dust, preventing it from entering the lower respiratory tract. In the narrow passages of the nose, cold air has time to heat up so that it can then pass through a number of other organs without causing inflammation of the bronchi and lungs.

The nasal cavity is limited by the palate, which consists of the hard (or bony) palate in front and the soft palate in the back, which does not contain bone. The oral cavity and tongue are also located nearby. The epiglottis is the entrance to the trachea, which in turn leads to the lungs, esophagus and stomach.

Internal structure of the nose

Inner parts of the nose:

• cavity;
• paranasal sinuses.

They are connected to each other, have a common muscular wall of the throat and communicate with the inner ear. Therefore, when there is inflammation of any internal ENT organ, there is a risk of developing secondary infection of all three sections and cavities of the throat and ear, for example, purulent otitis media is caused by the leakage of pus from the maxillary sinuses or sinus.

The picture below shows a cross-section of the structure of the nasopharynx: from the inside there is a nasal cavity connected to the throat and the mouth of the auditory tube.

The anatomy of the inside of the nose is very complex. The relief-shaped mucous membrane serves to warm and humidify the air, which then enters the bronchi and lungs. The following types of walls are unified in both cavities:

• Lateral wall - it consists of individual bones, the upper cheekbone, and the hard palate;
• The upper wall is represented by the ethmoid bone. The cranial nerves responsible for smell and touch pass through its openings;
• The lower wall consists of processes of the hard palate and maxillary bones.

Paranasal sinuses and their functions

The photo shows that in the area of ​​each shell there is an opening through which the sinuses communicate with the nasal cavity. For example, the cephaloid sinus communicates with the nasal cavity in the area of ​​the superior turbinate.

The frontal sinus communicates in the area of ​​the middle concha.

The maxillary sinus, like the frontal sinus, communicates with the nasal cavity at the middle concha.

The frontal sinus is located above the orbit and has an anastomosis in the middle concha.

The sphenoid sinus is located medial (center) to the orbit and has an anastomosis in the superior and inferior turbinates.

Turkish saddle. In its center is the pituitary fossa. In weakened people, the sinuses are often clogged with purulent contents, therefore, to prevent rhinitis, you need to rinse your nose every morning with saline solution at room temperature.

The olfactory zone is represented by special neurosensory cells that contain olfactory receptors. They are contained in the olfactory membrane and in the upper wall of each nasal passage. Olfactory receptors send signals to the first cranial nerve, which transmit them to the brain to the center of smell.

Rhinitis can lead to sinusitis or sinus inflammation. To prevent this complication, you need to start treatment in a timely manner (inhalations, vasoconstrictors, nasal drops).

Attention. Vasoconstrictor nasal drops can be used for no more than three days. Since atrophy of the mucous membrane is possible in the future.

The anatomical features of the nose are adapted for best work body. The wrong one can provoke improper outflow of tear fluid, then inflammation of the maxillary sinuses and sinuses.

Rhinoplasty is an operation that involves surgically straightening the nasal septum. The incorrect section of bone is removed and a plastic prosthesis is placed in its place.

Functions of the human nose

The nose performs the following functions:

• olfactory;
• attractive;
• respiratory.

Olfactory function. In the internal cavity there are olfactory receptors, with the help of which we can smell a wide variety of smells. With atrophy of the mucous membrane, we may lose our sense of smell.

Atrophy of the nasal mucosa may occur due to steam burns after taking certain medicines, due to a strong infectious process in the ENT organs and even when inhaling chemicals of various origins.

Respiratory function. The air enters the nose, where it is cleared of pathogenic bacteria and warmed, then goes to the lungs, which ensures the supply of oxygen to the blood and the possibility of life for a person.

Cavum nasi is a space that lies in the sagittal direction from the pyriform aperture to the choanae and is divided into two halves by a septum. The nasal cavity is limited by five walls: upper, lower, lateral and medial.
Top wall formed by the frontal bone, the inner surface of the nasal bones, the lamina cribrosa of the ethmoid bone and the body of the sphenoid bone.
Bottom wall formed by the bony palate, palatinum osseum, which includes the palatine process of the upper jaw and the horizontal plate of the palatine bone.
Lateral wall formed by the body of the maxilla, the nasal bone, the frontal process of the maxilla, the lacrimal bone, the labyrinth of the ethmoid bone, the inferior nasal concha, the perpendicular plate of the palatine bone and the medial plate of the pterygoid process.
Medial wall, or nasal septum, septum nasi osseum, divides the nasal cavity into two halves. It is formed by the perpendicular plate of the ethmoid bone and the ploughshare, above by the nasal spine of the frontal bone, spina nasalis, behind by the sphenoid crest, crista sphenoidalis, of the sphenoid bone, below by the nasal crest, crista nasales, the upper jaw and palatine bone. The nasal cavity opens in front with a pear-shaped aperture, apertura piriformis, and in the back with choanae. Choanae, choanae - paired internal openings of the nasal cavity that connect it with the nasal part of the pharynx.
On the lateral wall of the nasal cavity there are three nasal conchas: superior, middle and inferior, concha nasalis superior, media et inferior. The superior and middle turbinates belong to the labyrinth of the ethmoid bone, the inferior is an independent bone. The listed shells limit three nasal passages: upper, middle and lower, meatus nasalis superior, medius et inferior.
Superior nasal passage, meatus nasalis superior, lies between the superior and middle nasal conchae. The posterior cells of the ethmoid bone open into it. At the posterior end of the superior turbinate there is a sphenopalatine opening, foramen sphenopalatinum, leading into the fossa pterygopalatina, and above the superior turbinate there is a sphenoethmoidal recess, recessus spheno-ethmoidalis, in the area of ​​which the sinus of the sphenoid bone, sinus sphenoidalis, opens.
Middle nasal passage, meatus nasalis medius, located between the middle and inferior nasal concha. Within its boundaries, after removal of the middle shell, the semilunar foramen, hiatus semilunaris, opens. The posteroinferior part of the semilunar foramen expands, at the bottom of which there is an opening, hiatus maxillaris, leading into the maxillary sinus, sinus maxillaris. In the anterior-superior part of the nasal cavity, the semilunar foramen expands and forms a ethmoidal funnel, infundibulum ethmoidale, into which the frontal sinus, sinus frontalis, opens. In addition, the anterior and some middle ethmoidal cells open into the middle meatus and the semilunar foramen.
Lower nasal passage, meatus nasalis inferior, located between the bony palate and the inferior nasal concha. The nasolacrimal duct, canalis nasolacrimal, opens in it. In clinical (otolaryngological) practice, a puncture of the maxillary sinus is performed through the lower nasal passage for diagnostic and therapeutic purposes.
The slit-like space between the posterior portions of the turbinates and the bony nasal septum is called the common nasal meatus, meatus nasi communis. The section of the nasal cavity, located behind the nasal turbinates and the bony nasal septum, forms the nasopharyngeal passage, meatus nasopharyngeus, which opens into the posterior nasal openings - choanae.
Buttresses- these are bone thickenings in certain areas of the skull, interconnected by transverse crossbars, along which the force of pressure is transmitted to the cranial vault during chewing. Buttresses balance the amount of pressure that occurs during chewing, pushing and jumping. Between these thickenings are thin bone formations called weak points. It is here that fractures most often occur during physical activity, which does not coincide with the physiological acts of chewing, swallowing and speech. In clinical practice, fractures in the cervical region are more often observed lower jaw, angle and upper jaw, as well as the zygomatic bone and its arch. The presence of holes, crevices and weak spots in the bones of the skull determine the direction of these fractures, which is important to consider in oral surgery. In the upper jaw, the following buttresses are distinguished: frontonasal, collar-zygomatic, palatine and pterygopalatine; at the bottom - cellular and ascending.