Eye auxiliary apparatus: structure and functions

The eye is considered one of the key sensory organs. He plays a crucial role in the perception of the person around the world. In the diverse activities of people, the organ of vision is of paramount importance. Eyes catch light, send it to sensitive cells. A person can recognize a color and black and white image, see objects in the volume at different distances. The organ of vision is paired and located in the cranial fossa of the facial part. It is surrounded by an auxiliary apparatus of the eye.

Structure of the retina

The inner shell has two parts: a large rear and a smaller front. The latter combines iris and ciliary department. The visual part includes internal pigment and nervous areas. In the latter there are about 10 layers of cells. They enter the inner part of the shell with processes in the form of rods and cones. Due to them, the person perceives rays in daylight and twilight. Other nerve cells play a binding role. Their axons, joining a bundle, come out of the shell.

Auxiliary eye apparatus: anatomy

This department includes several elements that perform a number of important tasks. из: The auxiliary apparatus of the eye consists of:

1. Eyebrows.
2. Century.
3. The lacrimal department.
4. Muscle.
5. Conjunctiva.

Tasks

. First of all it is necessary to note the protective functions of the eye auxiliary apparatus . It ensures the moistening of the front surface of the organ of vision, preventing its drying. In addition, this department facilitates the removal of foreign particles. входит разрушение бактерий, которые попадают на поверхность органа. In the function of the auxiliary apparatus of the eye is the destruction of bacteria that fall on the surface of the organ. The department also contributes to the elimination of substances that are formed during stress and nervous tension. They come out with tears.

Muscles

A person has a unique eye structure. – отдел, без которого нормальная работа органа была бы невозможна. The auxiliary apparatus is the department, without which the normal operation of the organ would be impossible. Of particular importance is the musculature. To the apple are attached 4 straight (medial, lateral, lower, upper), 2 oblique (lower and upper) muscles. Almost all of them come out from the depth of the eye socket, starting from the tendon ring. The exception is the lower oblique muscle. Partly the fibers move away from the edges of the orbital (upper) slit. From the tendon ring, the muscle that provides the lifting of the eyelid originates. It is located in the orbit above the straight fiber. It ends in the thickness of the century. Straight muscles are directed along the walls of the orbit. They are located on the sides of the nerve. Ahead of the equator, at a distance of 5-8 mm from the corneal margin to the back of the muscle with the help of short tendons are weaved into the sclera. Straight muscles provide the rotation of the apple around the axes that cross each other. It moves right and left vertically and up and down horizontally. The lateral muscle turns the apple outward, the medial muscle - inside the vertical axis. In the fixation site of the first, a tendon stretching is formed. Most of its beams are weaved into the sclera. Some of them go forward and out. Subsequently they are fixed on the lateral wall. The lower and upper straight fibers allow the apple to rotate relative to the horizontal axis. The first participate in the movement down and inside, the latter - up and a bit outside.

The slanting upper muscle departs from the tendon ring. It lies in the upper medial area of the orbit. Near the lateral fossa of the fiber pass into a round thin tendon, covered with the synovial vagina. It passes through a block that looks like a ring represented by fibrous cartilage. Further, the tendon deviates somewhat posteriorly and outwardly. Passing under the direct upper muscle, it is fixed on the upper-lateral part of the apple at a distance of approximately 18 mm from the edge of the cornea. Slanting upper fibers provide rotation outside and down. The lower muscle departs from the orbital surface in the upper jaw next to the opening of the nasolacrimal canal. Then it goes to the outside and back, passes between the straight fibers and the wall of the eye socket. The muscle is fixed on the lateral surface behind the equator. It provides the rotation of the apple outside and up. работают согласованно. The muscular structures of the eye auxiliary apparatus work in concert. This they provide synchronism of the movement of the left and right apples.

Fascia

The glaznica, where the apple is located, is lined with the periosteum. In the region of the upper slit and the visual canal, it fuses with the dura mater. The apple surrounds the vagina or the tenon capsule. It connects to the sclera. The gap between the vagina and the surface of the apple is called the tenon (episcleral) space. On the back surface, the first fuses with the outer cavity of the optic nerve, and in front it approaches the conjunctival vault. Nerves and vessels, tendons of oculomotor fibers pass through the vagina. Front of the eye socket and its contents partially covered by a septum. It starts from the periosteum of the lower and upper edges and is attached to the cartilages of the eyelids. In the region of the inner eye angle, it joins with the medial ligament.

Fat body

Between the periosteum and the vagina of the apple, around the oculomotor fibers and the optic nerve is a clump of tissue. It is called the fatty body. It is permeated by connective tissue lintels. The fat body performs a depreciation function. The smaller part of it is outside the cone formed by a complex of muscles of the apple. It is adjacent to the walls of the eye socket. Most of the body is inside the cone, surrounded by a nerve.

Eyelids

They are divided into upper and lower. представляют собой кожные складки, пролегающие спереди яблока. These structures of the auxiliary apparatus of the eye are skin folds that run from the front of the apple. Eyelids cover it from below and from above. When closed, they completely cover the apple. When the state of the eyelids is open, the transverse slit is limited. From the lateral and medial sides, seals are closed up - spikes. They form the eye corners. In the area of the medial adhesion there is a slight elevation. It is called a teardrop. Around it is a lake. Inside the meat is a vertical small conjunctival fold - a semilunar fold. It is considered the remainder of the third (blinking) century, which is found in vertebrates. On the free edge of the lower and upper eyelids, next to the medial angle, outwardly from the lake is an elevation - a papilla. On top of it there is a hole - the beginning of the tear duct. In the region of the eye sockets, the folds of the eyelids pass into the integument of adjacent areas of the face. On the border with the forehead is a transversely directed roller, the surface of which is covered with hair. This is an eyebrow. The anterior surface of the eyelids is convex. It is covered with a thin skin, where there is a lot of sweat and sebaceous glands. The back is facing the eyeball. It has a concave shape and is covered with conjunctiva. , фактически защищается веками. Everything that pertains to the auxiliary apparatus of the eye is actually protected for centuries.

Connecting woven plate

It is located in the thickness of the lower and upper eyelids. According to its density, the connective tissue plate is similar to cartilage. It distinguishes the front and back surfaces, as well as the 2 edges - free and orbital. The posterior surface of the plate closely fuses with the conjunctiva. This determines the smoothness of the latter in this area. The anterior part of the cartilage of the eyelids is connected to the circular muscle fibers with the help of connective tissue. From the upper and lower surfaces to the medial wall, a common ligament passes along the posterior and anterior crest. It covers the tear sack. Towards the lateral wall follows the same ligament.

Free edge

It is confined to the front and back surfaces of the century. Glazed edges are fixed at the corresponding site of the orbit with the help of muscle fibers of the lower and upper cartilage. The fibers of the latter are attached to the inner surface. They join the muscle that provides the lifting of the upper eyelid. The lower muscle connects with the corresponding straight muscle of the apple. It is attached to the same edge of the cartilage. On the free edge are hairs - eyelashes.

The glands

Close to the back of the free edge are openings. They are the exit points of the sebaceous glands. Their initial parts are located inside the cartilaginous plate. In the upper eyelid, the sebaceous glands are larger than in the lower eyelid (30-40 versus 20-30). , следует также отметить, что на свободном крае между ресницами присутствуют отверстия, открывающие протоки потовых желез. Considering the structure of the eye, the auxiliary apparatus of the eye , it should also be noted that on the free edge between the eyelashes there are openings that open the ducts of the sweat glands.

Conjunctiva

The auxiliary device includes special indentations. They are formed at the site of the transition of the conjunctiva from the lower and upper eyelids to the apple. It, in turn, covers the front part, passes to the limb of the cornea. At the site of the transition to the sclera, a ring is formed. All the space from the apple in front and limited by conjunctiva is called a bag. It is closed with closed eyes, and when open, it has a message with the external environment. In the thick are solitary conjunctival glands.

Pathologies

. There are various diseases of the eye auxiliary apparatus . All of them require thorough diagnosis and proper treatment. отдел органа, нарушение его работы скажется на состоянии зрения. In connection with the fact that the apparatus of the eye is an auxiliary department of the organ, a violation of its work will affect the state of vision. When the first symptoms appear, specialists should be contacted immediately.

Blepharitis

), как выше было сказано, включены веки. In the apparatus of the eye (auxiliary ), as mentioned above, the eyelids are included. With inflammation of their edges, blepharitis is diagnosed. The etiology of pathology is very diverse. Blepharitis, in particular, can be caused by hypovitaminosis, anemia, helminthic invasions, gastrointestinal disorders, etc. As prerequisites for the onset of the disease, lacrimal pathologies, chronic conjunctivitis, exposure to smoke, dust act. Blepharitis can be ulcerative, scaly, simple, etc. Treatment is prescribed only by a doctor. It is mandatory to maintain hygiene conditions of life and work. With simple blepharitis appoint 1% of the rr diamond green or 1% mercury yellow ointment. With ulcerative disease, a compress of fish oil or oil is first applied to the eyes. In a complex course of pathology, autohemotherapy, physiotherapy, is used.

Dacryocystitis

особенно уязвим у новорожденных. The eye auxiliary apparatus is especially vulnerable in newborns. Often in infants diagnosed with dacryocystitis. It is an inflammation in a lacrimal sac. Dacryocystitis can also be detected in adults. In this case, as a rule, it is chronic. Prerequisites are inflammatory processes in the nasal cavity, paranasal sinuses, bones that surround the sac. These processes cause the delay and development of pathogenic microbes. In newborns, dacryocystitis is associated with preservation of the embryonic membrane covering the lower part of the tear-nasal canal. Therapy is performed by surgical methods. In the acute course of the pathology, anti-inflammatory agents are prescribed. After the suppression of inflammatory processes, surgery is performed.

Conjunctivitis

Protection of the organs of vision is the main task that the eye apparatus performs . отдел постоянно подвергается внешнему воздействию. The auxiliary department is constantly exposed to external influences. Conjunctivitis is one of the most common pathologies of the organ of vision. It is an inflammation in the connective membrane. Adenoviral conjunctivitis is spread by airborne droplets. Pathology develops sporadically, in the form of epidemic outbreaks. Most often it occurs in children's groups. The beginning of the course of the pathology is acute. Before the defeat of the eye usually there are diseases of the respiratory tract, the temperature rises, pre-limonic lymph nodes increase. Conjunctivitis is accompanied by photophobia, lacrimation, reddening and edema of the eyelids, hyperemia. Often there are follicles or films. The latter are detected, as a rule, in children.

Acute phase

The causative agents of pathology are staphylo-, strepto-, gono-, pneumococci, Koch-Wicks stick, etc. Usually, exogenous conjunctival lesion develops. Probably also an autoinfection. As suppositions supercooling or an overheat of an organism, a microtrauma of a conjunctiva act. The disease caused by the Koch-Wicks rod spreads through dirty hands and contaminated objects. In summer, in countries with a hot climate, epidemics often erupt.

Chronic course

It is due to prolonged irritation of the conjunctiva. Chronic disease becomes if the organ of vision is constantly exposed to chemical impurities, smoke, dust, etc. Prerequisites can be and avitaminosis, metabolic disorders, ametropia, persistent lesions of the lacrimal system, nose. Chronic conjunctivitis is manifested by burning, sensation of sand in the eyes, hyperemia, slight swelling. There is also a meager mucopurulent discharge. In the treatment, first of all, favorable hygienic conditions are created. Eliminate all the negative factors that can cause pathology. As a rule, local preparations are prescribed in the form of drops. This can be, for example, 025-033% zinc sulfate solution, supplemented with adrenaline and dicaine. If an exacerbation occurs, 30% of sulfacil sodium is administered, 10% of sulfapiridazine sodium is administered and 0.3% of synthomycin is administered.