Age-related anatomy of the eye - eye chambers, extraocular muscles. Chambers of the eye Structure of the anterior chamber angle

In the vision system, each element has a strict purpose, even the cameras of the eye, despite the fact that they represent only empty space, of a given volume are of great importance for the reliable operation of the visual apparatus.

After all, in nature there is nothing superfluous, and even cavities and voids in the structure internal organs are not random oversights, but rather, on the contrary, the high flight of scientific thought.

What are the cameras of the eye?

- closed, but communicating with each other through cavities filled with intraocular fluid. They ensure interaction between the tissues of the organs of vision, conduct light to, and participate in the refraction of light fluxes along with.

Structure

The visual apparatus has two cameras, one of which is located in the front part eyeball, and the second is in the back.

Thanks to these sections, the human eye receives the necessary fluid to ensure mobility, and also has the opportunity to get rid of excess moisture to protect the eye tissue from swelling.

The outer edge of the anterior chamber is the inner wall of the cornea; at the back, this compartment is limited by tissues and a small area.

The depth of such a capsule is uneven; the hollow formation reaches its greatest depth in the pupillary region, and towards the edges the reserves of empty space decrease.

Behind the first chamber there is a second rear compartment, which in its anterior part is limited by the iris and is connected to the rear.

Along the entire perimeter of its borders, the posterior chamber is penetrated by special zonular ligaments. Such connecting elements provide a strong connection and lens capsule.

It is the compression and relaxation of such ligaments, together with the ciliary muscle group, that provoke a change in the size of the lens, which in turn gives a person the opportunity to see equally well at different distances.

Functions

The cameras of the eyes perform a very important and responsible function in our vision system. The work of the processes of the ciliary body caused the formation of fluid in the space of the posterior ocular chamber.

This moisture is necessary in order to protect the delicate tissues of the eyeball from drying out and ensure its free movement throughout the space of the orbit.

At the same time, the accumulation of excess fluid in the eye area can lead to swelling of some parts of the eyeball and provoke a rather serious disorder in the visual apparatus.

Here the anterior chamber comes to the rescue, in the corner part of which there is an extensive system of drainage holes through which excess fluid freely leaves the eyeball.

The main purpose of these cameras is to maintain the normal state of all tissues of the eye; these compartments are also involved in transporting the light flux to the retina and refracting light rays.

Symptoms

The cameras of the eye perform a very important function in the functioning of the entire visual apparatus, so symptoms of a violation in their harmonious interaction should not be ignored.

All alarm signals can be divided into two categories: congenital and acquired disorders over the course of life.

Congenital defects, as a rule, include a change in the angle in the anterior chamber, a violation of this angle by remnants of embryonic tissue that have not resolved at the time of birth, or improper attachment of the iris tissue.

All other changes in the operation of the eye cameras are usually acquired during life and are caused by various injuries or diseases, both of the visual system and of the entire organism as a whole.

Diagnostics

Due to the high complexity of the structure of the visual system, many disorders in its functioning cannot be noticed during an external examination, therefore, to make a correct diagnosis, the patient is prescribed a full range of diagnostic laboratory tests.

To correctly assess the degree of damage to the eye chamber, examination can be performed under transmitted light conditions or using microscopes. The specialist may also need to measure the angle of the anterior chamber during a microscopic examination with the additional use of a magnifying lens.

In addition, in this perspective, optical and ultrasonic equipment is actively used, the depth of the chamber is assessed and measured. The degree of fluid outflow from the internal space of the eyeball is also determined.

Treatment

Treatment of dysfunction of the eye chambers or their structural elements can only be carried out in a specialized clinic using the full range of necessary equipment.

Basically, therapy in this case should be aimed at relieving the causes that provoked a disturbance in the functioning of the visual mechanism.

Anti-inflammatory therapy and procedures to relieve swelling that occurs due to improper drainage of excess fluid from the eyeball area can complement the drug course.

It is a space limited by the posterior surface of the cornea, the anterior surface of the iris and the central part of the anterior lens capsule. The place where the cornea passes into the sclera, and the iris into the ciliary body, is called the anterior chamber angle.

In its outer wall there is a drainage system (for aqueous humor) of the eye, consisting of a trabecular meshwork, scleral venous sinus (Schlemm's canal) and collector tubules (graduates).

Through the pupil, the anterior chamber freely communicates with the posterior one. In this place it has the greatest depth (2.75-3.5 mm), which then gradually decreases towards the periphery. True, sometimes the depth of the anterior chamber increases, for example, after removal of the lens, or decreases, in the case of detachment of the choroid.

The intraocular fluid that fills the chambers of the eye is similar in composition to blood plasma. It contains nutrients necessary for the normal functioning of intraocular tissues and metabolic products, which are then released into the bloodstream. The production of aqueous humor is occupied by the processes of the ciliary body; this occurs by filtering blood from the capillaries. Formed in the posterior chamber, moisture flows into the anterior chamber, then flowing out through the angle of the anterior chamber due to more low pressure venous vessels into which it is ultimately absorbed.

The main function of the eye cameras is to maintain relationships between intraocular tissues and participate in the conduction of light to the retina, as well as in the refraction of light rays together with the cornea. Light rays are refracted due to the similar optical properties of the intraocular fluid and the cornea, which together act like a lens that collects light rays, resulting in a clear image of objects appearing on the retina.

The structure of the anterior chamber angle

The anterior chamber angle is the zone of the anterior chamber, corresponding to the zone of transition of the cornea into the sclera, and the iris into the ciliary body. The most important part of this area is the drainage system, which ensures a controlled outflow of intraocular fluid into the bloodstream.

The drainage system of the eyeball involves the trabecular diaphragm, scleral venous sinus, and collector tubules. The trabecular diaphragm is a dense network with a porous-layered structure, the pore size of which gradually decreases outward, which helps in regulating the outflow of intraocular moisture.

The trabecular diaphragm can be distinguished

• uveal,
• corneo-scleral, as well as
• juxtacanalicular plate.

Having overcome the trabecular meshwork, the intraocular fluid enters the slit-like narrow space of Schlemm’s canal, located at the limbus in the thickness of the sclera of the circumference of the eyeball.

There is also an additional outflow pathway, outside the trabecular meshwork, called the uveoscleral. Up to 15% of the total volume of outflowing moisture passes through it, while fluid from the angle of the anterior chamber enters the ciliary body, passes along the muscle fibers, then penetrating into the suprachoroidal space. And only from here does it flow through the veins of graduates, directly through the sclera, or through Schlemm’s canal.

The tubules of the scleral sinus are responsible for the drainage of aqueous humor into the venous vessels in three main directions: into the deep intrascleral venous plexus, as well as the superficial scleral venous plexus, into the episcleral veins, and into the network of veins of the ciliary body.

Pathologies of the anterior chamber of the eye

Congenital pathologies:

• Lack of angle in the anterior chamber.
• Blockage of the angle in the anterior chamber by remnants of embryonic tissue.
• Anterior attachment of the iris.

Acquired pathologies:

• Blockade of the anterior chamber angle with the iris root, pigment, or other.
• Small anterior chamber, bombardment of the iris - occurs when the pupil is closed or circular pupillary synechia.
• Uneven depth in the anterior chamber - observed with post-traumatic changes in the position of the lens or weakness of the zonules.
• Precipitates on the corneal endothelium.
• Goniosynechia is adhesions in the corner of the anterior chamber of the iris and trabecular diaphragm.
• Recession of the anterior chamber angle is a splitting, rupture of the anterior zone of the ciliary body along the line that separates the radial and longitudinal fibers of the ciliary muscle.

Diagnostic methods for diseases of the eye chambers

• Transmitted light imaging.
• Biomicroscopy (examination under a microscope).
• Gonioscopy (study of the anterior chamber angle using a microscope and contact lens).
• Ultrasound diagnostics, including ultrasound biomicroscopy.
• Optical coherence tomography for the anterior segment of the eye.
• Pachymetry (assessment of the depth of the anterior chamber).
• Tonometry (determination of intraocular pressure).
• Detailed assessment of the production and outflow of intraocular fluid.

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Description

Anterior chamber of the eye It is customary to call the space limited by the posterior surface of the cornea, the anterior surface of the iris and partially the anterior surface of the lens. It has a certain depth and is made of transparent liquid.

Anterior chamber depth depends on the patient’s age, eye refraction and state of accommodation. The chamber fluid consists of a crystalloid solution with very little protein. In this regard, chamber moisture is almost invisible even with detailed biomicroscopy.

Research methodology

When examining the anterior chamber, you can use various biomicroscopy angle options. The lighting slit should be as narrow as possible and as bright as possible. Among lighting methods, preference should be given to research in direct focal light.

To judge the depth of the anterior chamber it is necessary perform biomicroscopy at a low angle. The microscope should be positioned strictly along the midline, with its focus set on the image of the cornea. By moving the microscope's focal screw forward, a clear image of the iris is obtained in the field of view. By assessing the degree of distance of the cornea from the iris (by the degree of displacement of the microscope focal screw), one can to a certain extent judge the depth of the anterior chamber. A more accurate determination of the depth of the anterior chamber is carried out using special additional settings (micrometric drum).

To study the state of chamber moisture a wider (larger) biomicroscopy angle should be used, for which the illuminator must be moved to the side. The microscope remains in the middle, zero position. The larger the biomicroscopy angle, the larger the apparent distance between the cornea and the iris appears. When the illuminator is positioned on the temporal side, the internal parts of the anterior chamber are examined. on the contrary, when moving the illuminator to the nasal side - its outer sections.

The anterior chamber of the eye is normal

During biomicroscopy, the anterior chamber appears as a dark, optically empty space. However, when studying some age groups, one can see in the moisture of the anterior chamber physiological inclusions. In children, wandering blood elements (leukocytes, lymphocytes) are found, in elderly patients - inclusions of degenerative origin (pigment, elements of a split-off lens capsule).

Under normal conditions, the moisture in the anterior chamber is in continuous slow motion. This is noticeable when observing the movement of physiological inclusions, and in some cases, elements of inflammatory origin that appear in the chamber humor during iridocyclitis. Meesmann associates the movement of chamber fluid with the existing difference in temperature of the fluid layers adjacent to the surface of the richly vascularized iris and located near the avascular cornea in contact with the external environment.

Temperature difference It is most pronounced in that portion of chamber moisture that is located with the eyelids open against the palpebral fissure. According to Meesmann, it reaches 4-7°, and the speed of movement of intraocular fluid in the specified zone is 1 mm and 3 seconds.

The flow of chamber moisture has vertical direction. The heated intraocular fluid entering the anterior chamber through the pupillary opening rises upward along the anterior surface of the iris. In the upper part of the chamber angle, it changes its direction and slowly falls down, moving along the posterior surface of the cornea (Fig. 53).

Rice. 53. Thermal current of intraocular fluid (diagram).

In this case, the intraocular fluid partially gives off heat through the avascular cornea into the surrounding atmosphere, as a result of which the speed of fluid movement slows down. In the lower parts of the anterior chamber, the moisture again changes its direction, rushing towards the iris. Contact with the iris ensures heating of the next portion of the intraocular fluid, which causes its further rise along the iris upward, towards the upper corner of the anterior chamber. Changing the position of the patient's head does not affect the circulation pattern of the chamber fluid.

In experiments with immersion of the cornea in a warm physiological solution, the temperature of which approaches the temperature of the internal parts of the animal's eye, it was obtained slowing down and completely stopping the flow of intraocular fluid. Something similar can be observed during long-term biomicroscopy of chamber moisture. The bright focal light usually heats some of the fluid moving down along the surface of the cornea, causing the speed of its movement to slow down, and sometimes the fluid begins to rise, which can be judged by observing particles suspended in it.

Chamber moisture flow rate depends not only on the temperature difference. The degree of viscosity of the intraocular fluid plays an undoubted role. Thus, with an increase in the protein content and chamber moisture, its viscosity increases, which leads to a slowdown in the movement of the liquid. According to Meesmann, if there is 2% protein in the anterior chamber fluid, its flow completely stops. After the concentration of protein fractions decreases, the normal movement of the chamber fluid is restored.

Cooling of chamber moisture, flowing along the posterior surface of the cornea, and the resulting slowdown in the speed of its current creates conditions for the deposition on the cornea of ​​cellular elements suspended in moisture and making repeated movements with it along the walls of the anterior chamber. This is how physiological deposits appear on the posterior surface of the cornea. They are located in its lower parts strictly along a vertical line, reaching the level of the lower pupillary edge. These deposits are observed quite often in children and young men and are called Ehrlich-Türk drip line. It is assumed that these deposits are nothing more than wandering blood elements.

If they do not follow in transmitted light, they have the appearance of translucent elements, the number of which ranges from 10 to 30 (Fig. 54).

Rice. 54. Ehrlich-Türk line.

When viewed under direct focal light, the deposits take on the appearance of white dots and appear less transparent.

These physiological deposits on the posterior surface of the cornea should be remembered when carrying out differential diagnosis with inflammatory changes in the chamber humor. At the same time, it must be taken into account that physiological deposits have a strictly defined localization, located in the lower parts of the cornea along the midline, and that they are not constant (they disappear during observation). The endothelium of the posterior surface of the cornea in the area of ​​their location is not changed. Pathological deposits occupy a significantly larger area of ​​the cornea, located not only along the midline, but also in its circumference, and are significantly more stable and persistent. The corneal endothelium around pathological deposits is usually swollen.

In elderly patients, the posterior surface of the cornea can be seen pigment that migrates here from the back surface of the iris, as well as elements of the exfoliated lens capsule. These deposits are usually characterized by a variety of localizations.

Pathological changes in the anterior chamber

Pathological conditions of the anterior chamber are expressed in changes in its depth, the appearance in its moisture of pathological inclusions associated with inflammation or injury, as well as in the presence of elements of incomplete reverse development of the embryonic vessels of the eye (see Biomicroscopy of the iris).

The main method for judging the depth of the anterior chamber is direct focal light examination. It is of great importance in the absence or slow recovery of the anterior chamber after antiglaucomatous operations and cataract extraction surgery.

Biomicroscopic examination convinces that the complete absence of the anterior chamber is extremely rare, mainly with old irreversible changes characterized by tight fusion of the posterior surface of the cornea with the anterior surface of the iris and lens. At the same time, it is often observed secondary glaucoma. More often, the absence of the anterior chamber is only apparent. Usually, having obtained a good optical section of the cornea, you can be convinced that in the area of ​​the pupil between the section of the cornea and the lens there is a thin capillary slit of a dark color, filled with chamber moisture. An increase in the width of this gap, as well as the appearance of thin layers of intraocular fluid above the lacunae and crypts of the iris, usually indicate the beginning of restoration of the anterior chamber.

A correct understanding of the depth of the anterior chamber and the dynamics of its restoration plays a huge role in such complications of fistulizing antiglaucomatous operations as choroidal detachment. As is known, with this complication, a shallow anterior chamber is observed on the side of choroidal detachment. Timely biomicroscopic examination and analysis of the depth of the anterior chamber help diagnose (taking into account other existing symptoms) choroidal detachment. This is of particular importance if the patient has a cloudy lens, which makes ophthalmoscopy impossible. Monitoring the depth of the anterior chamber over time correctly guides the doctor regarding the location of the detached choroid, which is of great importance in choosing a treatment method. long failure to restore the anterior chamber usually dictates the need to remove the choroidal detachment surgically.

Deep or uneven depth of the anterior chamber due to trauma to the eyeball indicates lens displacement(subluxation or dislocation).

Anterior chamber examination with iridocyclitis reveals biomicroscopic changes of inflammatory origin. The moisture of the anterior chamber becomes more noticeable, opalescent as a result of the appearance of an increased amount of protein in it. The above-described Tyndall phenomenon, for the study of which it is recommended to use a very narrow illumination slit or a round diaphragm opening. Against the background of diffusely turbid chamber moisture, fibrin threads and cellular inclusions - elements of precipitates - are often visible. The occurrence of the latter is associated with inflammation of the ciliary body, as evidenced by the histological composition of these inclusions (leukocytes, lymphocytes, ciliary epithelial cells, pigment, fibrin).

A dynamic examination with a slit lamp shows that with an increase in the protein content in the chamber moisture, i.e., as the moisture becomes more distinguishable, the speed of movement of the cellular elements and fibrin suspended in it decreases. Especially the flow of liquid in the lower parts of the chamber slows down, in the place where the fluid changes its direction, rushing from the cornea to the iris. Whirlpools and even stopping of the flow of chamber moisture usually occur here. This creates conditions for deposits on the posterior surface of the cornea. cell sediment precipitates.

Favorite localization of precipitates in the lower parts of the cornea is associated not only with the thermal current of the intraocular fluid. The weight (heaviness) of the precipitates themselves and the state of the corneal endothelium undoubtedly play a role in this process.

Various localization of precipitates is possible, but more often they are located in the lower third of the cornea in the form of a triangle, facing downward with its wide base. Larger precipitates are usually located at the base of the triangle, and smaller ones at the apex. In some cases, deposits are arranged in a vertical line, forming a spindle shape. Much less often, random, atypical localization of precipitates is observed (in the center, on the periphery of the cornea, in its paracentral sections), which is usually associated with the nature of the corneal lesion. For example, with focal keratitis and the accompanying iridocyclitis, precipitates are concentrated according to the location of the corneal lesion. In cases of severe iridocyclitis, a disseminated distribution of precipitates is observed throughout the posterior surface of the cornea.

An idea of ​​the localization of precipitates can be obtained by carrying out transmitted light examination. In this case, precipitates are revealed as dark-colored deposits of various sizes and shapes. Large, disc-shaped precipitates are observed, with clear boundaries and often protruding into the anterior chamber. These precipitates are also easily detected using conventional research methods. In addition to those indicated, there are small, point-like, dust-like or unformed precipitates.

For a more detailed examination of precipitates and to identify their true color, it is necessary to study in direct focal light with a slightly wider illumination slit. In most cases, precipitates are characterized by a white-yellow or grayish color, sometimes with a brownish tint. Some authors (Coerre, 1920) consider a certain type and size of precipitates to be pathognomonic for certain forms of iridocyclitis. Without completely sharing this opinion, we can say that the study of the size, shape and color of precipitates while taking into account other clinical symptoms and data from a general examination of the patient helps to classify iridocyclitis into the category of specific or nonspecific inflammation, as well as to assess to a certain extent the duration of the process, i.e., to answer the question whether iridocyclitis is in a progressive phase or a period of its reverse development has begun.

Chronic granulomatous inflammation of the vascular tract (iridocyclitis of tuberculous, syphilitic origin) is usually characterized by the appearance large white-yellow, formed precipitates with clear boundaries, prone to fusion (Fig. 55.1).

Fig. 65. Precipitates on the posterior surface of the cornea. 1 - decorated; 2 - unformed; 3 - lens.

Due to their typical appearance and color, such deposits are called “greasy” or “greasy” precipitates. They differ in the duration of their existence and often leave behind clouding of the cornea. According to A. Ya. Samoilov (1930), with tuberculous iridocyclitis, such precipitates are carriers of a specific infection on the corneal tissue, as a result of which parenchymal tuberculous keratitis can develop in the circumference of the precipitate.

A large group of nonspecific iridocyclitis is characterized by the appearance of very tender, unformed, dusty precipitates(Fig. 55.2) of an unstable nature. Sometimes they are detected in the form of a peculiar dustiness of the edematous endothelium of the cornea.

It should be noted that precipitates acquire their peculiar appearance only As the clinical manifestations iridocyclitis. During biomicroscopic examination in the first days of the disease, no pattern in the form and location of precipitates can be noted.

Upon the onset of the regressive phase of iridocyclitis chamber moisture becomes less saturated with protein, and the speed of its movement increases. This affects the size and shape of the precipitates. Point deposits quickly disappear without a trace, and formed precipitates significantly decrease in size, become flattened, and their boundaries become jagged and uneven. These changes can be associated with the resorption of fibrin and the migration of cellular elements forming the precipitate into the surrounding chamber fluid. When examined in transmitted light, it is clear that the precipitates become translucent and translucent.

As it dissolves precipitates acquire a brown or brown tint, which is associated with the exposure of one of the elements of the precipitate - a pigment, previously masked by a mass of other cellular elements. In the chronic course of iridocyclitis, precipitates can exist for months, often leaving behind light pigmentation.

In addition to precipitates of inflammatory origin, there are precipitates, the occurrence of which is associated with trauma to the lens - the so-called lens precipitates(Fig. 55.3). They are formed during spontaneous trauma to the lens, accompanied by significant disruption of the integrity of its anterior capsule, as well as after extracapsular cataract extraction surgery with incomplete extraction of the lens substance. In some cases, deposition of lens masses (precipitates) on the posterior surface of the cornea may accompany phacogenetic iridocyclitis. The occurrence of these precipitates is associated with the washing out of turbid lens masses by chamber moisture and their transfer during its conventional movement to the posterior surface of the cornea.

When examined with a slit lamp lens precipitates look like large, shapeless gray-white deposits. As they dissolve, they become looser, fluffier, and acquire a bluish color. Lens precipitates, as a rule, resolve without tears. Detection of such precipitates should not lead to a diagnosis of infectious iridocyclitis.

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The cavity of the eye contains light-conducting and light-refracting media: aqueous humor that fills its anterior and posterior chambers, the lens and the vitreous body.

Anterior chamber of the eye (camera anterior bulbi) is a space bounded by the posterior surface of the cornea, the anterior surface of the iris and the central part of the anterior lens capsule. The place where the cornea passes into the sclera, and the iris into the ciliary body, is called the anterior chamber angle ( angulus iridocornealis). In its outer wall there is a drainage system (for aqueous humor) of the eye, consisting of a trabecular meshwork, scleral venous sinus (Schlemm's canal) and collector tubules (graduates). Through the pupil, the anterior chamber freely communicates with the posterior one. In this place it has the greatest depth (2.75-3.5 mm), which then gradually decreases towards the periphery (see Fig. 3.2).

Posterior chamber of the eye (camera posterior bulbi) is located behind the iris, which is its anterior wall, and is bounded externally by the ciliary body and posteriorly by the vitreous body. The inner wall is formed by the equator of the lens. The entire space of the posterior chamber is penetrated by ligaments of the ciliary girdle.

Normally, both chambers of the eye are filled with aqueous humor, which in its composition resembles blood plasma dialysate. Aqueous humor contains nutrients, in particular glucose, ascorbic acid and oxygen, consumed by the lens and cornea, and removes waste metabolic products from the eye - lactic acid, carbon dioxide, exfoliated pigment and other cells.

Both chambers of the eye contain 1.23-1.32 cm3 of fluid, which is 4% of the total contents of the eye. The minute volume of chamber moisture is on average 2 mm3, the daily volume is 2.9 cm3. In other words, complete exchange of chamber moisture occurs within 10 hours.

There is an equilibrium between the inflow and outflow of intraocular fluid. If for any reason it is disrupted, this leads to a change in the level of intraocular pressure, upper limit which normally does not exceed 27 mm Hg. (when measured with a Maklakov tonometer weighing 10 g). The main driving force that ensures the continuous flow of fluid from the posterior chamber to the anterior chamber, and then through the angle of the anterior chamber outside the eye, is the pressure difference in the eye cavity and the venous sinus of the sclera (about 10 mm Hg), as well as in the said sinus and anterior ciliary veins.

lens (lens) is a transparent semi-solid avascular body in the form of a biconvex lens, enclosed in a transparent capsule, with a diameter of 9-10 mm and a thickness (depending on accommodation) of 3.6-5 mm. The radius of curvature of its anterior surface at rest of accommodation is 10 mm, the posterior surface is 6 mm (with a maximum accommodation stress of 5.33 and 5.33 mm, respectively), therefore, in the first case, the refractive power of the lens averages 19.11 diters, in the second - 33.06 ditr. In newborns, the lens is almost spherical, has a soft consistency and a refractive power of up to 35.0 diters.

In the eye, the lens is located immediately behind the iris in a depression on the anterior surface of the vitreous body - in the vitreous fossa ( fossa hyaloidea). In this position it is held by numerous glassy fibers, which together form the suspensory ligament (ciliary girdle).

Posterior surface of the lens. like the anterior one, it is washed by aqueous humor, since it is separated from the vitreous body almost along its entire length by a narrow gap (retrolental space - spaiium retrolentale). However, along the outer edge of the vitreous fossa, this space is limited by the delicate annular ligament of Wieger, located between the lens and the vitreous body. The lens is nourished through exchange processes with chamber moisture.

Vitreous chamber of the eye (camera vitrea bulbi) occupies the posterior part of its cavity and is filled with the vitreous body (corpus vitreum), which is adjacent to the lens in front, forming a small depression in this place ( fossa hyaloidea), and throughout the rest of its length it is in contact with the retina. The vitreous body is a transparent gelatinous mass (gel-type) with a volume of 3.5-4 ml and a weight of approximately 4 g. It contains large quantities of hyachuronic acid and water (up to 98%). However, only 10% of water is associated with the components of the vitreous body, so fluid exchange in it occurs quite actively and, according to some data, reaches 250 ml per day.

Macroscopically, the vitreous stroma itself is isolated ( stroma vitreum), which is pierced by a vitreous (clockets) canal, and the hyaloid membrane surrounding it from the outside (Fig. 3.3).

The glassy stroma consists of a fairly loose central substance, in which there are optically empty zones filled with liquid ( humor vitreus), and collagen fibrils. The latter, becoming denser, form several vitreal tracts and a denser cortical layer.

The hyaloid membrane consists of two parts - anterior and posterior. The border between them runs along the dentate line of the retina. In turn, the anterior limiting membrane has two anatomically separate parts - lenticular and zonular. The boundary between them is the circular hyaloidocapsular ligament of Wieger. durable only in childhood.

The vitreous body is tightly connected to the retina only in the region of its so-called anterior and posterior bases. The first refers to the area where the vitreous body is simultaneously attached to the epithelium of the ciliary body at a distance of 1-2 mm anterior to the serrated edge (ora serrata) of the retina and 2-3 mm posterior to it. The posterior base of the vitreous body is the zone of its fixation around the disc optic nerve. It is believed that the vitreous body also has a connection with the retina in the area of ​​the macula.

Glassy(clockets) channel (canalis hyaloideus) of the vitreous body begins in a funnel-shaped expansion from the edges of the optic disc and passes through its stroma towards the posterior capsule of the lens. The maximum channel width is 1-2 mm. In the embryonic period, the vitreous artery passes through it, which is empty by the time the child is born.

As already noted, there is a constant flow of fluid in the vitreous body. From the posterior chamber of the eye, the fluid produced by the ciliary body enters the anterior part of the vitreous through the zonular fissure. Next, the fluid that has entered the vitreous body moves to the retina and the prepapillary opening in the hyaloid membrane and flows out of the eye both through the structures of the optic nerve and through the perivascular spaces of the retinal vessels.

The chambers of the eye are closed, interconnected spaces containing intraocular fluid. There are two chambers in the eyeball: anterior and posterior, which normally communicate with each other through the pupil.

The anterior chamber is located directly behind the cornea, bounded posteriorly by the iris. The posterior chamber lies behind the iris, extending into the vitreous. Normally, the chambers of the eye have a constant volume due to the strictly regulated formation and outflow of intraocular fluid. The formation of intraocular fluid occurs in the posterior chamber, thanks to the ciliary processes of the ciliary body, and it flows mostly through a system of drainages located in the corner of the anterior chamber - the area of ​​​​the transition of the cornea to the sclera and the ciliary body to the iris.
The main function of the eye cameras is to maintain the normal relationship of intraocular tissues, as well as participate in transmitting light to the retina and, in addition, in refracting light rays together with the cornea. The refraction of light rays is ensured by the same optical properties of the cornea and intraocular fluid, which together act as a lens collecting light rays, due to which a clear image is formed on the retina.

The structure of the chambers of the eye

The anterior chamber is limited externally by the inner surface of the cornea, that is, the endothelium, along the periphery by the outer wall of the angle of the anterior chamber, behind by the anterior surface of the iris and the anterior lens capsule. It has an uneven depth - the greatest up to 3.5 mm in the area of ​​the pupil, then towards the periphery it decreases. However, in some conditions the depth of the anterior chamber may increase, for example, after removal of the lens, or decrease, for example, with choroidal detachment.
The posterior chamber is located behind the anterior chamber and, accordingly, its anterior boundary is the posterior leaf of the iris, the outer is the inner surface of the ciliary body, the back is the anterior part of the vitreous, and the inner is the equator of the lens. The entire space of the posterior chamber of the eye is penetrated by numerous thin threads, the so-called ligaments of Zinn, connecting the lens capsule with the ciliary body. Due to tension or relaxation of the ciliary muscle, and then the ligaments, the shape of the lens changes and a person has the opportunity good vision at different distances.

The aqueous humor that fills the entire space of the chambers of the eye is similar in composition to blood plasma. It contains nutrients necessary for the functioning of intraocular tissues, as well as metabolic products, which are then released into the bloodstream.
The chambers of the eye contain only 1.23-1.32 cm3 of aqueous humor, but strict correspondence between the production and outflow of aqueous humor is extremely important for the eye. Any disturbance in this system can lead to an increase in intraocular pressure, for example, with glaucoma, or a decrease, for example, with subatrophy of the eyeball, each of these conditions is dangerous in terms of complete blindness and loss of the eye.
The production of aqueous humor occurs in the processes of the ciliary body, due to the filtration of blood from the capillary blood flow. Having formed in the posterior chamber, aqueous humor enters the anterior chamber and then flows out through the angle of the anterior chamber due to the lower pressure in the venous vessels, into which the aqueous humor is ultimately absorbed.

The structure of the anterior chamber angle

The anterior chamber angle is the area in the anterior chamber corresponding to the transition zone of the cornea to the sclera and the iris to the ciliary body. The most important part of this area is the drainage system, which ensures a controlled outflow of intraocular moisture into the bloodstream.

The drainage system of the eyeball consists of the trabecular diaphragm, scleral venous sinus and collector tubules. The trabecular diaphragm is a dense network with a porous and layered structure, and the pore sizes gradually decrease outward, regulating the outflow of intraocular moisture. The uveal, corneoscleral and juxtacanalicular plates of the trabecular diaphragm are distinguished. Having overcome the trabecular meshwork, the aqueous humor enters the narrow slit-like space or Schlemm’s canal, which is located in the thickness of the sclera at the limbus around the circumference of the eyeball.
There is also an additional outflow pathway, bypassing the trabecular meshwork, the so-called uveoscleral. It accounts for up to 15% of the total volume of outflowing aqueous humor, while moisture enters from the angle of the anterior chamber into the ciliary body, passing along the muscle fibers, and then enters the suprachoroidal space, from where it flows either through the veins of the graduates, directly through the sclera, or through Schlemm's canal.
The collector tubules of the scleral sinus drain aqueous humor into the venous vessels in three main directions: into the deep intrascleral and superficial scleral venous plexuses, into the episcleral veins, and into the venous network of the ciliary body.

Methods for diagnosing diseases of the eye chambers

• Inspection in transmitted light.
• Biomicroscopy – examination under a microscope.
• Gonioscopy is an examination of the anterior chamber angle under a microscope using a contact lens.
• Ultrasound diagnostics, including ultrasound biomicroscopy.
• Optical coherence tomography of the anterior segment of the eye.
• Pachymetry of the anterior chamber - assessment of chamber depth.
• Tonometry is a more detailed assessment of the production and outflow of intraocular fluid.
• Tonography – determination of the level of intraocular pressure.

Symptoms of pathologies of the chambers of the eye

Congenital changes:

• Absence of anterior chamber angle.
• Blockage of the anterior chamber angle by remnants of embryonic tissue that have not resolved at the time of birth.
• Anterior attachment of the iris.

Purchased changes:

• Blockage of the anterior chamber angle by the root of the iris, pigment, and so on.
• Small anterior chamber and bombardment of the iris - occurs with circular pupillary synechia or fusion of the pupil.
• Uneven depth of the anterior chamber - observed due to changes in the position of the lens after injury or weakness of the zonules of Zinn in some diseases.
• Hypopyon is an accumulation of pus in the anterior chamber of the eye.
• Precipitates on the corneal endothelium.
• Hyphema is an accumulation of blood in the anterior chamber.
• Goniosynechia is adhesions of the iris with the trabecular diaphragm in the corner of the anterior chamber.
• Recession of the anterior chamber angle is a rupture, splitting of the anterior section of the ciliary body along the line separating the longitudinal and radial fibers of the ciliary muscle.