intraocular fluid or aqueous humor is a kind of internal environment of the eye. Its main depots are the anterior and posterior chambers of the eye. It is also present in the peripheral and perineural fissures, suprachoroidal and retrolental spaces.

In its chemical composition, aqueous humor is analogous to cerebrospinal fluid. Its amount in the eye of an adult is 0.35-0.45, and in early childhood - 1.5-0.2 cm 3. The specific gravity of moisture is 1.0036, the refractive index is 1.33. Therefore, it practically does not refract rays. Moisture is 99% water.

Most of the dense residue is made up of anorganic substances: anions (chlorine, carbonate, sulfate, phosphate) and cations (sodium, potassium, calcium, magnesium). Most of all in the moisture of chlorine and sodium. A small proportion is accounted for by protein, which consists of albumins and globulins in a quantitative ratio similar to blood serum. Aqueous moisture contains glucose - 0.098%, ascorbic acid, which is 10-15 times more than in the blood, and lactic acid, because. the latter is formed in the process of lens exchange. The composition of aqueous humor includes various amino acids - 0.03% (lysine, histidine, tryptophan), enzymes (protease), oxygen and hyaluronic acid. There are almost no antibodies in it and they appear only in the secondary moisture - a new portion of the liquid formed after the suction or expiration of the primary aqueous humor. The function of aqueous humor is to provide nutrition to the avascular tissues of the eye - the lens, the vitreous body, and partially the cornea. In this regard, a constant renewal of moisture is necessary, i.e. outflow of waste fluid and inflow of freshly formed.

The fact that the intraocular fluid is constantly being exchanged in the eye was also shown in the time of T. Leber. It was found that the fluid is formed in the ciliary body. It is called primary chamber moisture. It enters mostly in the rear chamber. The posterior chamber is bounded by the posterior surface of the iris, the ciliary body, the ligaments of zon, and the extrapupillary part of the anterior lens capsule. Its depth in various departments varies from 0.01 to 1 mm. From the posterior chamber through the pupil, the fluid enters the anterior chamber - a space bounded in front by the back surface of the iris and lens. Due to the valvular action of the pupillary edge of the iris, moisture cannot return back to the posterior chamber from the anterior chamber. Further, the spent aqueous humor with tissue metabolism products, pigment particles, cell fragments is removed from the eye through the anterior and posterior outflow tracts. The anterior outflow tract is the Schlemm canal system. Fluid enters the Schlemm's canal through the anterior chamber angle (ACA), an area bounded anteriorly by trabeculae and Schlemm's canal, and posteriorly by the root of the iris and the anterior surface of the ciliary body (Fig. 5).

The first obstacle in the way of aqueous humor from the eye is trabecular apparatus.

On cross section, the trabecula has a triangular shape. Three layers are distinguished in the trabecula: uveal, corneoscleral, and porous tissue (or the inner wall of Schlemm's canal).

Uveal layer consists of one or two plates, consisting of a network of crossbars, which are a bundle of collagen fibers covered with endothelium. Between the crossbars there are slots with a diameter of 25 to 75 mu. On the one hand, the uveal plates are attached to the Descemet's membrane, and on the other hand, to the fibers of the ciliary muscle or to the iris.

Corneoscleral layer consists of 8-11 plates. Between the crossbars in this layer there are elliptical holes located perpendicular to the fibers of the ciliary muscle. With tension of the ciliary muscle, the openings of the trabeculae expand. The plates of the corneoscleral layer are attached to the Schwalbe ring, and on the other hand to the scleral spur or directly to the ciliary muscle.

The inner wall of Schlemm's canal consists of a system of argyrophilic fibers enclosed in a homogeneous substance rich in mucopolysaccharides. In this tissue, there are rather wide Sonderman canals with a width of 8 to 25 mu.

Trabecular fissures are abundantly filled with mucopolysaccharides, which disappear when treated with hyaluronidase. The origin of hyaluronic acid in the chamber angle and its role have not been fully elucidated. Obviously, it is a chemical regulator of the level of intraocular pressure. Trabecular tissue also contains ganglion cells and nerve endings.

Schlemm's channel is an oval-shaped vessel located in the sclera. The channel clearance is on average 0.28 mm. From the Schlemm's canal in the radial direction, 17-35 thin tubules depart, ranging in size from thin capillary filaments of 5 mu, to trunks up to 16r in size. Immediately at the exit, the tubules anastomose, forming a deep venous plexus, representing gaps in the sclera lined with endothelium.

Some tubules run straight through the sclera to the episcleral veins. From the deep scleral plexus, moisture also goes to the episcleral veins. Those tubules that go from Schlemm's canal directly to the episclera, bypassing the deep veins, are called water veins. In them, one can see for some distance two layers of liquid - colorless (moisture) and red (blood).

Posterior outflow tract These are the perineural spaces of the optic nerve and the perivascular spaces of the retinal vascular system. The angle of the anterior chamber and the Schlemm's canal system begin to form already in the two-month-old fetus. In a three-month-old, the angle is filled with mesoderm cells, and in the peripheral sections of the corneal stroma, the cavity of the Schlemm's canal is distinguished. After the formation of the Schlemm's canal, the scleral spur grows in the corner. In a four-month-old fetus, corneoscleral and uveal trabecular tissue differentiate from mesoderm cells in the corner.

The anterior chamber, although morphologically formed, however, its shape and size are different from those in adults, which is explained by the short sagittal axis of the eye, the peculiarity of the shape of the iris and the convexity of the anterior surface of the lens. The depth of the anterior chamber in a newborn in the center is 1.5 mm, and only by the age of 10 does it become like in adults (3.0-3.5 mm). By old age, the anterior chamber becomes smaller due to the growth of the lens and sclerosis of the fibrous capsule of the eye.

What is the mechanism for the formation of aqueous humor? It has not yet been finally resolved. It is regarded both as a result of ultrafiltration and dialysate from the blood vessels of the ciliary body, and as an actively produced secret of the blood vessels of the ciliary body. And whatever the mechanism of formation of aqueous humor, we know that it is constantly produced in the eye and flows out of the eye all the time. Moreover, the outflow is proportional to the inflow: an increase in inflow increases the outflow, respectively, and vice versa, a decrease in inflow reduces the outflow to the same extent.

The driving force that causes the continuity of the outflow is the difference - a higher intraocular pressure and a lower one in the Schlemm's canal.

Lecture number 6.

Glaucoma.

The biggest danger in glaucoma is the threat of irreversible blindness. Glaucoma in adults develops after 40-45 years in 1.0-1.5% of the population. In children, glaucoma is less common - one case per 10,000 children, but every tenth child goes blind from it.

Given the rapid loss of vision in congenital glaucoma, it should be diagnosed in maternity hospitals by obstetrician-gynecologists, neonatologists, and micropediatricians. Newborns with diagnosed glaucoma should be urgently referred to an ophthalmologist for surgical treatment.

With an acute attack of glaucoma, emergency medical care is provided, so paramedical workers constantly encounter such patients. Their timely and competent help can be decisive in preventing vision loss. There is no prevention of glaucoma, there is only prevention of blindness from it, and it consists in early detection and early treatment of patients. In the prevention of blindness from glaucoma, medical literacy of the population plays an important role. Early access to a doctor, early diagnosis, timely and adequate treatment give hope for the preservation of vision in patients with glaucoma until old age.

Hydrodynamics of the eye.

Glaucoma occurs with a violation of hydrodynamics (fluid movement) in the eye. In order to understand the causes of violations of hydrodynamics, let us recall the basics of anatomy and physiology.

All organs and tissues of the body have some turgor due to internal and extracellular pressure. The value of such pressure usually does not exceed 2-3 mm Hg. Art. The value of intraocular pressure significantly exceeds the value of tissue fluid pressure and ranges from 15 to 24 mm Hg. Art.

The measurement of intraocular pressure is called tonometry. Tonometry is carried out by applying a load on the eye - a tonometer, which, when measured, squeezes the eye and thereby increases intraocular pressure. This pressure is called tonometric pressure in contrast to the true intraocular pressure, which can be calculated from tonometry data. It is clear that the true intraocular pressure is somewhat less than the tonometric one.

In Russia, tonometric pressure is called intraocular pressure and is indicated in millimeters of mercury. The limits of the norm of tonometric intraocular pressure, obtained by measuring with a Maklakov tonometer (weighing 10 g), range from 18 to 27 mm Hg. Art., true - from 15 to 24 mm Hg. Art. Moderately elevated pressure is considered to be 28-32 mm Hg. Art., high - 33 mm Hg. Art. and more.

Intraocular pressure in children and adults is almost the same. It is 1.5 mm Hg. Art. higher in newborns and decreases after 70 years. Intraocular pressure is constantly changing. With a sharp closure of the eyelids, it rises to 50 mm Hg. Art., when blinking - by 10 mm Hg. Art. There was a daily fluctuation in the norm up to 5 mm Hg. Art. (a stronger fluctuation is a pathology), and in the morning it is higher. The difference in intraocular pressure in different eyes is also normally 4-5 mm Hg. Art. If these figures exceed 5 mm Hg. Art. (intraocular pressure in the morning is 24 mm Hg, and in the evening - 18 mm Hg), it is necessary to suspect glaucoma and examine the patient, even with formally normal intraocular pressure.

The maintenance of constancy of intraocular pressure is based on two processes: the secretion of intraocular fluid and the rate of its outflow from the eye. Changes in any of them lead to a violation of the hydrodynamics of the eye.

The secretion of intraocular fluid is carried out by the ciliary body. Chamber moisture is approximately 75% formed due to active transport and 25% - due to "passive" ultrafiltration. Aqueous moisture circulates almost exclusively in the anterior segment of the eye. It is involved in the metabolism of the lens, the cornea and maintains a certain level of intraocular pressure.

A decrease in the secretion of intraocular fluid is observed with iridocyclitis, trauma, and leads to hypotension of the eye. Increased secretion can lead to an increase in intraocular pressure. However, in 95% of cases, glaucoma is caused by obstruction of the outflow of fluid from the eye - this is the so-called retention glaucoma.

The intraocular fluid is produced by the ciliary body and immediately enters the posterior chamber of the eye, located between the lens and the iris. Fluid enters the anterior chamber through the pupil. It is delimited in front by the cornea, behind the iris and the lens (iridocrystalline membrane). At the junction of the cornea and iris is the anterior chamber angle (ACA). In the anterior chamber, the fluid cycles under the influence of temperature changes and goes into the APC, and from there through the trabecula into the venous vessels.

For the occurrence of glaucoma in the APC, signs of dysgenesis must appear. If dysgenesis is gross and the anatomy of the APC is sharply disturbed, then congenital glaucoma occurs, with less severe changes in the APC - juvenile glaucoma, with small signs of dysgenesis, which are regarded as nuances of the structure of the APC - primary adult glaucoma.

A transparent jelly-like liquid fills the chambers of the visual organ. The rotation of aqueous humor is called the hydrodynamics of the eye. This process maintains an optimal level of ophthalmotonus, and also affects blood circulation in the vessels of the eye. Violation of the hemo- and hydrodynamics of the eyes leads to a malfunction of the optical system.

Chamber fluid formation

The exact pattern of development of aqueous humor is not yet fully understood. Anatomical facts, however, indicate that it is the processes of the ciliary body that produce this fluid. Passing its way from the back to the anterior chamber, it affects the following areas:

• ciliary body;
• back of the cornea;
• iris;
• lens.

Then moisture seeps into the venous sinus of the sclera through the trabecular meshwork of the anterior chamber angle of the eye. Following this, the fluid is in the vorticose, intra- and episcleral venous plexus. It is also reabsorbed by the capillaries of the ciliary body and the iris. Thus, for the most part, chamber moisture rotates in the anterior part of the visual organ.

The composition of the aqueous liquid

Pathology disrupts the blood supply to the organs of vision.

Chamber fluid in its structure is not similar to blood plasma, although it is produced from it. The composition of moisture is adjusted as it circulates. If we compare the plasma composition with the liquid of the anterior chamber, it can be noted that the latter has a number of distinctive features:

• increased acidity;
• the predominance of sodium and potassium;
• the presence of glucose and urea;
• low dry matter mass - almost 7 times less (per 100 ml);
• low percentage of proteins - does not exceed 0.02%;
• more chlorides;
• high concentration of acids - ascorbic and lactic;
• low specific gravity - 1.005;
• the presence of hyaluronic acid.

drainage system

Trabecula

The ethmoid ligament closes the edges of the internal scleral groove. The diaphragm separates the sinus from the anterior chamber. Corneoscleral and uveal trabeculae, as well as juxtacanalicular (porous) tissue, are its constituents. Aqueous moisture passes through the cribriform ligament. The contraction of meridional and circular fibers promotes filtration. This effect is explained by the change in the size and shape of the holes, as well as the ratio of the plates to each other.

If the Brücke muscle contracts, more moisture seeps through the net. When circular fibers contract, fluid movement is reduced.

Schlemm's channel

The eye has a complex anatomical structure.

The sinus is named after the anatomist Friedrich Schlemm. The channel is located in the sclera and is a circular venous vessel. It is located on the border of the cornea and iris, and is separated from the anterior chamber of the organ of vision by the ethmoid ligament. Due to the unevenness of the inner wall of the channel, there are "pockets" in it. The main function of the sinus is to transport fluid from the anterior chamber to the anterior ciliary vein. Thin vessels emanate from it, which form the venous plexus. They are usually called graduates of the Schlemm Canal.

collector channels

The venous plexus takes place on the outside of the sinus and in the outer balls of the sclera. So, there are 4 types of plexuses:

• Narrow short collectors. They connect the canal with the intrascleral plexus.
• Single large vessels called "water veins". They store liquid - pure or with blood streaks.
• short channels. They leave the scleral sinus, stretch along it and re-enter the canal.
• Separate ducts that act as connecting channels with the venous network of the ciliary body.

Glaucomas, etiology, classification, diagnostics, clinic, conservative (ophthalmohypotensive drugs) and surgical treatment, prevention. Differential diagnosis. Congenital glaucoma, classification, clinic, treatment. Tonometry technique

1.Relevance

The term "glaucoma" originally comes from the ancient Greek word glaucos, meaning "grey-blue". Unfortunately, we do not know exactly why and when this name first appeared, but we can assume that it describes the color of an eye blind from glaucoma.

Glaucoma refers to chronic diseases of the eye. Its main symptom complex is characterized by an increase in intraocular pressure (IOP), glaucomatous optic neuropathy (GON) and a progressive deterioration in the visual functions of the eye. Every year, 1 in 1,000 people over the age of 40 develop glaucoma again. The incidence of the population in this age group is 1.5%. Despite advances in treatments, glaucoma remains one of the leading causes of reduced vision and irreversible blindness. In Russia, 14-15% of the blind have lost their sight due to glaucoma, with a total number of patients exceeding 750 thousand people.

According to many researchers, the prevalence of glaucoma is increasing every year. If in 1997 in Russia it was 698 thousand, then in 2009 it was already 1205 thousand people. Of these, 60% have advanced stages, 70 thousand patients are blind from glaucoma. According to the forecast for 2020, the number of patients with glaucoma in the world will be 80 million people, of which 11 million are blind in 2 eyes. In the world every minute 1 person goes blind from glaucoma, and every 10 minutes 1 child.

Glaucoma belongs to the category of chronically current incurable diseases. The fact of establishing the diagnosis of glaucoma determines the life-long medical examination of this group of patients. Observation and treatment is carried out even after successful hypotensive operations or normalization of IOP in other ways.

An increased level of ophthalmotonus is one of the leading, but by no means the only risk factor for the progression of the glaucoma process. Therefore, the fact of lowering IOP should in no case lull the vigilance of the attending physician. The main criteria for observation in this case will be the state of the optic nerve head (observation of the dynamics of the size and shape of excavation), as well as changes in the central and peripheral fields of vision.

Glaucoma- a chronic eye disease, accompanied by a tirade of symptoms:

Constant or periodic increase in IOP;

Characteristic changes in the field of vision;

Regional excavation of the optic nerve.

Hydrodynamics of the eye

Intraocular fluid (1.5 - 4 mm³ / min) is continuously produced by the epithelium of the processes of the ciliary body and in a smaller amount during ultrafiltration from the capillary network. Moisture first enters the posterior chamber of the eye, the volume of which is about 80 mm³, and then passes through the pupil into the anterior chamber (volume 150 - 250 mm³), which serves as its main reservoir.

The outflow of aqueous humor (AU) is carried out through the drainage system of the eye, which is located in the corner of the anterior chamber of the eye, formed by the cornea and iris.

Drainage system of the eye It consists of the trabecular apparatus, the scleral sinus (Schlemm's canal) and the collector tubules that flow into the scleral veins. At the apex of the angle of the anterior chamber is the trabecular apparatus, which is an annular crossbar thrown over the apex of the angle. The trabecula has a layered structure. Each layer (there are 10-15 in total) is a plate consisting of collagen fibrils and elastic fibers, covered on both sides with a basement membrane and endothelium. There are holes in the plates, and between the plates there are gaps filled with aqueous humor. At the apex of the angle is the juxtacanalicular layer, which separates the trabecular apparatus from the Schlemm's canal. It consists of 2-3 layers of fibrocytes and loose fibrous tissue and provides the greatest resistance to the outflow of intraocular fluid from the eye. The outer surface of the juxtacanalicular layer is covered with endothelium containing "giant" vacuoles, which are dynamic intracellular tubules through which the intraocular fluid passes from the trabecular apparatus to the Schlemm's canal.

Figure 1. Aqueous humor flows through the trabecular meshwork into the canal of Schlemm.

Schlemm's canal (scleral sinus) is a circular fissure lined with endothelium and located in the posterior part of the angle of the anterior chamber. It is separated from the anterior chamber by a trabecula; outside the canal are the sclera and episclera with venous and arterial vessels. Aqueous moisture flows from Schlemm's canal through 20-30 collector tubules into the episcleral veins (recipient veins).

Figure 2. Anterior chamber angle: a - trabecular apparatus, b - Schlemm's canal, c - aqueous humor collectors.

The pathogenesis of open-angle glaucoma The pathogenesis of glaucoma includes three main pathophysiological mechanisms: hydromechanical, hemocirculatory and metabolic.

The first of them begins with a deterioration in the outflow of intraocular fluid and an increase in IOP.

The hydromechanical mechanism implies a violation of the hydrodynamics of the eye with a subsequent increase in ophthalmotonus, which causes a decrease in perfusion blood pressure, as well as the deformation of two relatively weak structures - the trabecular diaphragm in the drainage system of the eye and the cribriform plate of the sclera.

Outward displacement of the trabecular diaphragm leads to a further deterioration in the outflow of intraocular fluid due to blockade of the scleral sinus, and the cribriform plate of the sclera to the infringement of the optic nerve fibers in the tubules of the cribriform plate.

Hemocirculatory disorders can be divided into primary and secondary. Primary ones precede an increase in IOP, secondary ones arise as a result of an increased IOP effect on the hemodynamics of the eye.

Among the causes of metabolic shifts are hemocirculatory disorders leading to ischemia and hypoxia. The age-related decrease in the activity of the ciliary muscle, the vascular network of which is involved in the nutrition of the avascular trabecular diaphragm, has a negative effect on the metabolism of the drainage system of the eye.

Classification of glaucoma

From a practical point of view, the classification signs of glaucoma that are most in demand are the following.

Origin : primary and secondary glaucoma.

In primary glaucoma, pathological processes have strictly intraocular localization - they occur in the angle of the anterior chamber, the drainage system of the eye, or in the head of the optic nerve. They precede the manifestation of clinical symptoms and represent the initial stage of the pathogenetic mechanism of glaucoma.

In secondary glaucoma, the cause of the disease can be both intra- and extraocular disorders. Secondary glaucoma is a side and optional consequence of other diseases (for example, uveitis, vascular accidents, diabetes mellitus, retinal detachment, intraocular tumors, trauma, abnormal position of the lens or changes in its structure).

According to the mechanism of increasing IOP: open-angle and closed-angle.

Figure 3 Anterior chamber angle in open-angle glaucoma (left) and angle-closure glaucoma with synechiae (right).

Open angle glaucoma characterized by the progression of the pathological triad in the presence of an open angle of the anterior chamber.

This group includes the following nosological forms.

Simple primary open-angle glaucoma (POAG) occurs over the age of 35 years, the pathogenetic mechanism of development is trabeculopathy and functional trabecular block (scleral sinus block), increased IOP, changes in the optic disc, retina, visual functions, characteristic of glaucoma.

Exfoliative open-angle glaucoma (EOAG) is associated with (pseudo)exfoliative syndrome, develops in the elderly or senile age, is characterized by the deposition of exfoliative material in the anterior segment of the eye, trabeculopathy, canalicular block, increased IOP, glaucomatous changes in the optic disc, retina, and the state of visual functions.

Pigmentary glaucoma (PG) develops at a young and middle age in individuals with pigment dispersion syndrome, often combined with a simple form of POAG, spontaneous stabilization of the glaucoma process is possible.

Normal pressure glaucoma (NPG) occurs over the age of 35 years, IOP is within the normal range, but the level of individual tolerant IOP is reduced. Changes in the optic disc, retina and visual functions characteristic of glaucoma. The disease is often combined with vascular dysfunction. In most cases, the disease can be considered as a variant of POAG with an extremely low tolerance of the optic nerve even to a normal level of ophthalmotonus.

PRIMARY GLAUCOMA.

SECONDARY GLAUCOMA.

UDC 617.7 - 007.681 - 021.5 - 07 - 08 - 089

Printed by decision of the CMS and RIS of the Kirov State Medical Academy (protocol No. ___ dated "___" __________ 2012)

primary glaucoma. Secondary glaucoma: A manual for interns and clinical residents of the second year of study / Comp. HELL. Chuprov, Yu.V. Kudryavtseva, I. A. Gavrilova, L. V. Demakova, Yu. A. Chudinovskikh - under the general. ed. HELL. Chuprova - Kirov: KSMA. - 2012. - 119 p.

In "Primary glaucoma. Secondary glaucoma” presents detailed systematized information on the pathology of ophthalmotonus. The presented material meets the modern requirements of medical science. The manual is supplied with numerous drawings, diagrams, tables, illustrations.

The manual is intended for interns and clinical residents of the second year of study.

Reviewers:

Director of the State Budgetary Institution "Ufa Research Institute of Eye Diseases of the Academy of Sciences of the Republic of Belarus", Professor M. M. Bikbov

Doctor of Medical Sciences, Head of the Department of Hospital Surgery

Kirov State Medical Academy, Professor Bakhtin V.A.

Chuprov A.D., Kudryavtseva Yu.V., Gavrilova I.A., Demakova L.V., Chudinovskikh Yu.A. - Kirov, 2012

© GBOU VPO Kirov State Medical Academy of the Ministry of Health and Social Development of Russia, 2012

List of conventional abbreviations………………………………6

Foreword…………………………………………………….7 Guidelines……...……………………………....7
1. The concept of glaucoma…………………………..……………..9
2. Anatomy of the drainage system and hydrodynamics of the eye……………………………………………………………...9 2.1. Aqueous moisture….…….…………………… ……………9 2.2. Eye chambers…………………………………………..10 2.2.1. Front camera…………………………………………………………………………………………11 2.2.2. Rear camera……………….…………………………………………………………………………………………………11 2.2.3. Anterior chamber angle. Trabecular pathway of aqueous humor outflow………………………………………………………………………………………………………………………………………………………………………………………………………………………………………11 2.2.4. Uveoscleral pathway of aqueous humor outflow…………………………………………………………….....13 3. Classification of glaucoma…………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………….13 3. Classification of glaucoma…………………………………… 14 3.1 Clinical forms………….………………………..15 3.2. Stages of glaucoma………………………………………...17 3.3. The level of intraocular pressure…………………...18 3.4. Stages of the glaucoma process………………………..18 4. Diagnosis of glaucoma………………………………………………………18 4.1. Study of intraocular pressure and eye hydrodynamics………………………………………..19 4.2. Examination of the fundus…………………………...20 4.3. Examination of the visual field……………………………....24 4.4. Gonioscopy…………………………………………..25 5. Glaucoma in children………………………………………………30 5.1. Congenital glaucoma……………………..………….30 5.2. Infantile glaucoma or delayed congenital glaucoma………………….…………………………………….33 5.3. Primary juvenile glaucoma……………………33 6. Primary open-angle glaucoma…………………34 6.1. Risk factors………………………………………...35 6.2. Etiology……………………………………………...35 6.3. Etiopathogenetic links………………………..36 6.4. Pathogenesis of glaucomatous lesions…………...38 6.5. Clinic………………………………………………..39 6.6. Hydrodynamics of the eye………………………………....45 6.7. Course of primary open-angle glaucoma…...45 6.8. Pseudoexfoliative glaucoma…………………....45 6.9. Pigmentary glaucoma………………………………...47 6.10. Normal pressure glaucoma…………………….49 7. Primary angle-closure glaucoma………………….51 7.1. Primary angle-closure glaucoma with pupillary block………………………………………………………….51 7.2. Primary angle-closure glaucoma with flat iris…………………………………………………….....52 7.3. Creeping angle-closure glaucoma……………..54 7.4. Primary angle-closure glaucoma with vitreocrystalline block………………………………...55 7.5. Acute attack of angle-closure glaucoma……….55 7.6. Subacute attack of angle-closure glaucoma…...57 8. Treatment of glaucoma…………………………………………...57 8.1. Medicamentous treatment of glaucoma…………………………………………………………………………………………………………………………………………………………………………………..57 8.1.1. General principles of therapy………………………….57 8.1.2. Characteristics of antihypertensive drugs……………………………………………………….....61 8.2. Treatment of an acute attack of glaucoma………………..70 8.3. Neuroprotection in glaucoma……………………....71 8.4. Criteria for the effectiveness of treatment…………………..74 9. Laser treatment of glaucoma………………. ……………76 10. Surgical treatment of glaucoma………….………....80 10.1. Indications for surgical treatment…………....81 10.2. Background…………………………………….....81 10.3. Basic methods of operations in primary open-angle glaucoma………………………………..…86 10.3.1. Trabeculectomy…………………………….…..86 10.3.2. Non-penetrating deep sclerectomy……....88 10.4. Surgical treatment of primary angle-closure glaucoma………………………………………………….…....91 10.4.1. Iridectomy……………………………………..91 10.4.2. Iridocycloretraction……………………..…….92 10.5. Operations for congenital glaucoma……………....95 10.5.1. Goniotomy……………………………………....95 10.5.2. Sinustrabeculectomy………………………….98 10.6. Surgical methods for reducing the secretion of aqueous humor…………………………………………………99
11. Situational tasks on the topic …………………..……101 12. Test tasks on the topic ……………………….........104 13. Answers to test tasks… ………………………...113 14. Standards for solving situational problems…………..…..114 Conclusion…………………………………..…………… ..119 List of recommended literature ..………………..…..120

LIST OF CONVENTIONAL ABBREVIATIONS

BP - blood pressure

intraocular fluid - intraocular fluid

WHO - World Health Organization

IOP - intraocular pressure

GDH - goniodysgenesis

ONH - head of the optic nerve

NPH - normal pressure glaucoma

GON - glaucomatous optic neuropathy

optic disc - optic disc

drugs - medicines

NDSE - non-penetrating deep sclerectomy

OAG - open angle glaucoma

PVG - primary congenital glaucoma

PG - pigmentary glaucoma

PDS - pigmentary retinal degeneration

PIG - primary infantile glaucoma

PACG - primary angle-closure glaucoma

LPO - lipid peroxidation

POAG - primary open-angle glaucoma

PUG - primary juvenile glaucoma

PES - pseudoexfoliative syndrome

TVGD - tolerant intraocular pressure

APC - anterior chamber angle

CVV - central retinal vein

CHO - ciliochoroidal detachment

EOAG - exfoliative open-angle glaucoma

FOREWORD

The problem of glaucoma is one of the most urgent in modern ophthalmology due to the high prevalence and severity of outcomes of this disease. According to WHO, the number of patients with glaucoma in the world is currently more than 70 million people, and by 2020 this number is expected to increase to 79.6 million people. In Russia, there is also an increase in the number of patients with glaucoma: according to Libman E.S., for the period 1994 - 2002. the frequency of glaucoma has increased from 3.1 to 4.7 per 1000 population, the number of patients with glaucoma at the moment has exceeded 1 million people.

The general prevalence of the population increases with age: it occurs in 0.1% of patients aged 40-49 years, 2.8% - at the age of 60-69 years, 14.3% - over the age of 80 years. The frequency of congenital glaucoma varies from 0.03 to 0.08% of eye diseases in children, but in the overall structure of childhood blindness, 10–12 fall to its share.

The training manual provides detailed systematized information about the pathology of ophthalmotonus. The presented material meets the modern requirements of medical science. The manual is supplied with numerous drawings, diagrams, tables, illustrations. For self-control, test tasks and situational tasks have been developed.

METHODOLOGICAL INSTRUCTIONS

Textbook “Primary glaucoma. Secondary glaucoma” for interns and clinical residents of the second year of study.

The purpose and objectives of the tutorial: To acquaint interns and clinical residents with the main nosological forms of glaucoma. To teach how to diagnose glaucoma, prescribe conservative treatment, conduct a differential diagnosis and determine the presence of indications for laser and surgical treatment. To acquaint students with modern principles of surgical treatment of glaucoma.

According to the curriculum, 4 hours of practical training and 41.5 hours of independent activity are allocated for interns to study this topic; for clinical residents - lecture 2 hours, practical training - 8 hours, independent activity 80 hours. Independent work includes preparation for practical exercises, examination of patients with glaucoma in the clinic, supervision of patients in the department, assistance in surgical operations for glaucoma.

The textbook was compiled in accordance with the state educational standard in ophthalmology for interns and clinical residents. Built according to the thematic lesson plan. The manual provides a detailed systematic presentation of information about glaucoma, clinic, diagnosis and modern methods of its treatment. The manual is equipped with numerous drawings, diagrams and tables, illustrations

must know: pathogenesis of glaucoma, its main nosological forms, their clinical symptoms, diagnostic measures, modern methods of glaucoma treatment, know the criteria for referring a patient for surgical treatment.

As a result of studying the topic, interns and clinical residents should be able to: examine patients with glaucoma, examine the anterior segment of the eye on a slit lamp, examine the fundus, measure intraocular pressure, and determine the boundaries of the field of view.

THE CONCEPT OF GLAUCOMA

Glaucoma- a large group of eye diseases characterized by a constant or periodic increase in IOP caused by a violation of the outflow of aqueous humor from the eye. The consequence of the increase in pressure is the gradual development of visual impairments characteristic of the disease and glaucomatous optic neuropathy.

ANATOMY OF THE DRAINAGE SYSTEM OF THE EYE AND HYDRODYNAMICS OF THE EYE

The eyeball contains several hydrodynamic systems associated with the circulation of aqueous humor, vitreous humor, uveal tissue fluid and blood. The circulation of intraocular fluids provides a normal level of intraocular pressure and nutrition of all tissue structures of the eye.

aqueous humor

Aqueous moisture is a transparent liquid, which is a solution of salts. It fills the anterior and posterior chambers of the eye. Aqueous moisture circulates mainly in the anterior segment of the eyeball. It is involved in the metabolism of the lens, cornea and trabecular apparatus, plays an important role in maintaining a certain level of intraocular pressure. Aqueous moisture is formed mainly by processes of the ciliary body.

Chamber moisture is formed from blood plasma by diffusion from the vessels of the ciliary body. But the composition of chamber moisture differs markedly from blood plasma. It should also be noted that the composition of the chamber moisture is constantly changing as the chamber fluid moves from the ciliary body to the Schlemm's canal. The fluid produced by the ciliary body can be called primary chamber moisture, this moisture is hypertonic and differs significantly from blood plasma. During the movement of fluid through the chambers of the eye, exchange processes occur with the vitreous body, lens, cornea, and trabecular region. Diffusion processes between chamber moisture and iris vessels slightly smooth out the differences in the composition of moisture and plasma.

In humans, the composition of the anterior chamber fluid is well studied: this fluid is more acidic than plasma, contains more chlorides, lactic and ascorbic acids. The chamber moisture contains a small amount of hyaluronic acid (it is not in the blood plasma). Hyaluronic acid is slowly depolymerized in the vitreous body by hyaluronidase and enters the aqueous humor in small aggregates.

Of the cations in moisture, Na and K predominate. The main non-electrolytes are urea and glucose. The amount of proteins does not exceed 0.02%, the specific gravity of moisture is 1005. The dry matter is 1.08 g per 100 ml.

Eye cameras

Front camera

The space, the anterior wall of which is formed by the cornea, the posterior wall by the iris, and in the pupil area by 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 angle of the anterior chamber. At the top of the angle of the anterior chamber is the supporting framework of the angle of the chamber - the corneoscleral trabecula. Trabecula, in turn, is the inner wall of the venous sinus of the sclera, or Schlemm's canal.

rear camera

It is located behind the iris, which is its anterior wall. The ciliary body serves as the outer wall, the anterior surface of the vitreous body serves as the posterior wall. The entire space of the posterior chamber is permeated with fibrils of the ciliary girdle, which support the lens in a suspended state and connect it to the ciliary body.

2.2.3. Anterior chamber angle.Trabecular outflow tract of aqueous humor

In the outer wall of the angle of the anterior chamber is the drainage system of the eyeball, consisting of the trabecular diaphragm, scleral venous sinus and collector tubules.
The trabecular diaphragm has the appearance of a porous annular mesh (reticulum trabeculare) of a triangular shape. Its apex is attached to the anterior edge of the internal scleral sulcus, which borders the edge of the Descemet's membrane of the cornea and forms the anterior boundary ring of Schwalbe (Schwalbe G., 1887). The base of the trabecular diaphragm is associated with the scleral spur and partly with the longitudinal fibers of the ciliary muscle and the root of the iris.

Structurally, the considered trabecula is not homogeneous and consists of three main parts - uveal, corneal-scleral (larger in size) and tender pericanal.
The first two trabeculae have a layered-lamellar structure. Moreover, each plate, consisting of collagen tissue, is covered on both sides with a basement membrane and endothelium, and is penetrated by very thin holes. Between the plates, which are arranged in parallel rows, there are gaps filled with aqueous humor.
The uveal trabecula, running from the anterior edge of the internal scleral sulcus to the top of the scleral spur and further, thickening, to the root of the iris, consists of 1-3 layers of the plates mentioned above and freely, as through a large sieve, passes the filtered liquid. The corneal-scleral trabecula already contains up to 14 layers of the same plates, which form slit-like spaces at each level, divided into sections by processes of endothelial cells. Here, the liquid is already moving in two different directions - transverse (along the holes in the plates) and longitudinal (along the interplate slots).

The pericanalicular part of the trabecular diaphragm has a loose fibrous structure, from the canal side it is covered with a thin membrane and endothelium. At the same time, the pericanalicular part does not contain clearly defined outflow tracts (Rohen J., 1986) and, perhaps, therefore, it has the greatest resistance. The last obstacle to the chamber fluid filtering into a narrow slit-like space called the venous sinus of the sclera (sinus venosus sclerae) or Schlemm's canal (Schlemm, 1827) is its endothelium, which contains giant vacuoles. It is believed that the latter play the role of intracellular tubules, through which aqueous humor eventually enters the Schlemm canal (Kayes J., 1967). Schlemm's canal is a narrow annular fissure within the space of the internal scleral groove. Its average width is 300-500 microns, height - 25 microns, the inner wall is often uneven, with pockets and covered with thin and long endothelial cells. The lumen of the channel can be not only single, but also multiple with sectional partitions. Graduates of the scleral sinus, of which there are from 37 to 49 (Batmanov Yu.E., 1968), are diverse and remove aqueous humor in three main directions:
1) into deep intrascleral and superficial scleral venous plexuses (through narrow and short collector tubules);
2) into the episcleral veins (by means of single large "watery veins" emerging on the surface of the sclera and described in 1942 by Asher;
3) into the venous network of the ciliary body.

Visual inspection of the angle of the anterior chamber is possible only with the help of special optical devices - gonioscopes or goniolenses. The former are based on the principle of refraction of light rays towards the studied section of the angle of the anterior chamber, and the latter are based on their reflection from the structures under consideration. With a normal open angle of the anterior chamber, the following structural elements are visible (in the direction from the cornea to the iris): the anterior border ring of Schwalbe whitish (corresponding to the anterior edge of the internal scleral groove), trabecula (rough grayish strip), scleral venous sinus, posterior border ring Schwalbe (corresponding to the scleral spur) and the ciliary body. The width of the angle of the anterior chamber corresponds to the distance between the anterior boundary ring of Schwalbe and the iris, and therefore, according to the availability of inspection of its zones listed above.