Functions and structure of the sclera of the eye. Various types of diseases. Functions of the sclera of the eyes in humans and possible pathologies What is the sclera and its function

Hello dear readers!

I present to your attention another article from the "Structure of the eye" section.

Today we will talk about the sclera - the main part of the fibrous membrane of the eyeball. This also includes the cornea, but we will talk about it in the next article.

Visually, we see the sclera as a dense white layer of the front surface of our eye, but in fact it covers 5/6 of the area of ​​the eyeball.

In my article I want to talk about the structural features of the sclera and the important functions that it performs.

What is sclera

The outer fibrous membrane of the eye is represented by the sclera, which borders the cornea in front.

But unlike the transparent cornea, the sclera is an opaque shell that has a dense composition that resembles a tendon in appearance.

Normally, the sclera is white, so we usually call its visible part "the white of the eye."

In newborns, it may have a blue tint, and in older people it may be yellowish.

On top of the sclera (albumen) is covered with a transparent layer - the conjunctiva.

The structure of the albuginea

The thickness and density of the sclera in different areas is different and varies from 0.3 to 1.0 mm.

The greatest thickness - at the base of the optic nerve - is up to 1.2 mm. In front, the shell becomes thinner, and at the border of the connection with the cornea, it does not exceed 0.3-0.4 mm.

In the center of the posterior sclera is a multilayer lattice plate through which the optic nerve and retinal vessels pass.

There are three layers in the structure of the sclera:

• episclera - is a superficial and loose layer. It is permeated with blood vessels and is characterized by an excellent blood supply;
• the sclera itself - it consists of collegue fibers and is similar in structure to the cornea. In the space between the fibers are fibrocides responsible for the production of collagen.

  Collagen fibers are arranged in a chaotic sequence, which explains the opacity of the albuginea.

• brown plate (inner layer) - got its name because of the large number of pigment-containing cells - chromatophores, which give this layer a brown color.

blood supply

The vascular supply system of the sclera is divided into deep and superficial.

The anterior (external) sections are rich in excellent blood flow. This is due to the fact that the blood vessels, passing through the entire thickness of the oculomotor muscles, exit directly to the anterior part of the eye.

Blood vessels pass through the thickness of the sclera through emissaries - special openings that are through channels.

The shell also contains its own vessels, but in minimal quantities. Basically, the sclera is nourished by transit conjunctival vessels.

Structural features

Since the structure of the sclera is a connective tissue, this membrane is subject to various pathological processes.

A thin sclera is observed in children, with age it acquires the necessary thickness.

As the body ages, the fibrous membrane becomes thinner, which is associated with a loss of elasticity and ability to stretch, as well as an increase in its water content.

In places where it becomes thinner, the appearance of protrusions or tears is possible.

Such vulnerable areas are the points of attachment of the tendons of the eye muscles, in which the thickness of the sclera is minimal. Therefore, most often with eye injuries, ruptures occur here.

The sclera has practically no nerve endings in its composition, as a result of which it is insensitive when exposed.

The purpose of the sclera

To ensure the operability of the eye apparatus, the fibrous membrane performs a number of important functions:

1. Protective
   Of all the functions performed by the sclera, the main one is protective. Its purpose is to protect all other membranes of the eye from mechanical influences (for example, shocks) or adverse external factors.
2. frame
   The sclera is a support for all the internal structures of the eye and its external components, which are located outside the eye apparatus.

   Thanks to the sclera, a constant spherical shape of the eye is maintained, vessels, ligaments, nerves, as well as six external muscles are attached to it, which are responsible for the direction of gaze and ensure synchronous rotation of the two eyes in different directions.

3. Optical
   Since the sclera is an opaque tissue, its function is to protect the retina from excessive illumination, in particular from the appearance of so-called side lights and glare, which provides a person with good vision.
4. Stabilization

   The sclera is directly involved in maintaining intraocular pressure. This ensures the normal functioning of all structures of the eye apparatus.

   With pressure, the collagen fibers that make up the sclera are stretched. Gradually stretching and thinning from that, the sclera ceases to perform its functions qualitatively.

   A circular groove runs along the sclera from the inside of the anterior margin, at the bottom of which there is an oval-shaped vessel - Shlemov Canal (Shlema), also called the venous sinus of the sclera. This channel exists to drain the intraocular fluid and maintain its optimal circulation.

These are the structural features and the main functions of the albuginea of ​​the eye. In one of the following articles, we will talk about diseases of the sclera and their treatment.
Be healthy!

The human eye is a complex natural optical device through which 90 percent of the information for the brain enters. The sclera is a functional element.

The condition of the shell indicates eye diseases, other pathologies of the body. In order to recognize the disease in time, one should understand what the sclera are.

shell structure

The sclera is the outer tunica of dense connective tissue that protects and holds the internal functional elements.

The white of the eye consists of bundle-like, randomly arranged collagen fibers. This explains the opacity, different density of the fabric. The thickness of the shell varies between 0.3 - 1 mm, it is a capsule of fibrous tissue of an unequal thickness.

The white of the eye has a complex structure.

1. The outer layer is a loose tissue with an extensive vascular system, which is subdivided into a deep and superficial vascular network.
2. Actually sclera, consists of collagen fibers and elastic tissues.
3. The deep layer (brown plate) is located between the outer layer and the choroid. Consists of connective tissue and pigment cells - chromatophores.

The posterior part of the eye capsule looks like a thin plate with a lattice structure.

Functions of the sclera

The fibers of the cover are arranged randomly, protect the eye from the penetration of sunlight, which ensures effective vision.

The sclera performs important physiological functions.

1. The eye muscles, which are responsible for the mobility of the eye, are attached to the tissues of the capsule.
2. The ethmoid arteries of the posterior part penetrate through the sclera.
3. A branch of the ophthalmic nerve approaches the eyeball through the capsule.
4. The tissue of the capsule serves as a sheath.
5. Whirlpool veins exit the eye through the protein body, which provide the outflow of venous blood.

The protein shell, due to its dense and elastic structure, protects the eyeball from mechanical injuries, negative environmental factors. Protein serves as a framework for the muscular system, ligaments of the organ of vision.

What should the sclera of a healthy person look like?

The sclera is normally white with a bluish tint.

Due to the small thickness, the child has blue sclera, through which the pigment and the vascular layer shine through.

A change in color (dullness, yellowness) indicates disturbances in the body. The presence of yellowish areas on the surface of the protein indicates eye infections. A yellow tint can be a symptom of liver disorders, hepatitis. In infants, the covering is thinner and more elastic than in adults. Slightly blue sclera is normal at this age. In elderly people, the cover thickens, becomes yellow due to the deposition of fat cells, loose.

Blue sclera syndrome in humans is caused genetically or by a violation of the formation of the eyeball in the prenatal period.

Changing the type of protein is a justified reason to visit a doctor. The condition of the cover affects the functioning of the visual system. Diseases of the sclera are classified as congenital and acquired.

Congenital pathologies

Melanosis (melanopathy)- a congenital disease, which is expressed by pigmentation of the cover with melanin. Changes appear in the first year of life. The proteins of the child have a yellowish tint, pigmentation appears in the form of spots or stripes. The color of the spots may be gray or light purple. The cause of the anomaly is a violation of carbohydrate metabolism.

blue sclera syndrome often accompanied by other eye defects, anomalies of the musculoskeletal system, hearing aid. The deviation is innate. Blue sclera may indicate an iron deficiency in the blood.

Acquired diseases

Staphyloma - refers to acquired diseases. Manifested by thinning of the shell, protrusion. It is a consequence of eye diseases associated with destructive processes.

Episcleritis is an inflammation of the surface of the integument, accompanied by nodular seals around the cornea. Often resolves without treatment, may recur.

Scleritis is an inflammatory process affecting the inner layers of the scleral body, accompanied by pain. In the focus, a rupture of the eye capsule may form. The disease is accompanied by immunodeficiency, tissue edema.

Necrotizing scleritis- develops as a result of prolonged rheumatoid arthritis. It is manifested by thinning of the membrane, the formation of staphyloma.

Diseases of inflammatory origin can occur as a result of infections, disorders of the organs of the human body.

A timely visit to the doctor helps to identify diseases of the sclera in a timely manner, determine the cause and begin treatment.

Article author: Nina Gerasimova

- This is an inflammatory process that affects the entire thickness of the outer connective tissue membrane of the eyeball. It is clinically manifested by hyperemia, vascular injection, edema, pain on palpation of the affected area or movements of the eyeball. Diagnosis of scleritis is reduced to an external examination, biomicroscopy, ophthalmoscopy, visometry, tonometry, fluorescein angiography, ultrasound (US) in B-mode, and computed tomography. Depending on the form of the disease, the treatment regimen includes local or systemic use of glucocorticoids and antibacterial agents. With purulent scleritis, an abscess opening is shown.

General information

Scleritis is an inflammatory disease of the sclera characterized by a slowly progressive course. Among all forms, the anterior scleritis is the most common (98%). The defeat of the posterior sclera is observed only in 2% of patients. Variants of the course of pathology without necrosis prevail over necrotizing ones, which is associated with a favorable prognosis. In rheumatoid and reactive chlamydial arthritis, diffuse variants of the disease are common. In 86% of cases of ankylosing spondylitis, nodular scleritis is diagnosed. In 40-50% of patients, pathological changes in the sclera are combined with joint damage of inflammatory origin, and in 5-10% of cases, arthritis is accompanied by scleritis. The disease is more common in females (73%). The peak incidence is between 34 and 56 years of age. In children, pathology is observed 2 times less often.

Causes of scleritis

The etiology of scleritis is directly related to a history of systemic diseases. The triggers for scleral lesions are rheumatoid arthritis, Wegener's granulomatosis, juvenile idiopathic, reactive chlamydial or psoriatic arthritis, polyarthritis nodosa, ankylosing spondylitis, and polychondritis, characterized by a relapsing course. Less commonly, this pathology develops in the postoperative period after surgical removal of the pterygium or traumatic injury. Clinical cases of infectious scleritis in patients with a history of vitreoretinal surgery are described.

Scleritis of infectious etiology often leads to dissemination of the process from the ulceration zone on the cornea. Also, inflammation of the paranasal sinuses can be a source of infection. The most common causative agents of the disease are Pseudomonas aeruginosa, the Varicella-Zoster virus and Staphylococcus aureus. In rare cases, scleritis is of fungal origin. Drug lesion of the sclera often develops when taking mitomycin C. Risk factors - osteoarticular forms of tuberculosis in history, systemic inflammatory diseases.

Symptoms of scleritis

From a clinical point of view, in ophthalmology, anterior (non-necrotizing, necrotizing), posterior and purulent scleritis are distinguished. Non-necrotizing lesions of the sclera are diffuse or nodular. Necrotizing may or may not be accompanied by an inflammatory process. In some cases, the course of scleritis is characterized by short-term self-terminating episodes. At the same time, the pathological process in the sclera provokes its necrosis involving the underlying structures. This disease is characterized by an acute onset, less often sluggish variants are observed. With diffuse scleritis, the entire anterior section of the outer connective tissue membrane of the eyeball is involved in the inflammatory process. Nodular lesions are accompanied by a decrease in visual acuity.

The anterior scleritis is characterized by a slowly progressive course. This form is accompanied by a binocular lesion of the organ of vision. Patients note severe pain when touching the edema projection area, photophobia. The long course of the disease leads to damage to the sclera around the circumference of the limbus (annular scleritis) and the occurrence of severe keratitis, iritis or iridocyclitis. With purulent scleritis, a rupture of the abscess membranes is possible, which leads to the development of iritis or hypopyon.

With necrotic lesions of the sclera, patients note increasing pain, which later becomes permanent, radiating to the temporal region, superciliary arch and jaw. The pain syndrome is not stopped by taking analgesics. Necrotizing scleritis is complicated by perforation of the sclera, endophthalmitis, or panophthalmitis. In the posterior form of the pathology, patients complain of pain when moving the eyeball, limiting its mobility. Postoperative scleritis develops within 6 months after surgery. In this case, a site of local inflammation is formed, which is replaced by necrosis. A decrease in visual acuity is observed only when the inflammatory process spreads to the adjacent structures of the eyeball or the development of secondary glaucoma.

Diagnosis of scleritis

Diagnosis of scleritis includes an external examination, biomicroscopy, ophthalmoscopy, visometry, tonometry, fluorescein angiography, B-mode ultrasound (US), and computed tomography. An external examination of patients with anterior scleritis reveals swelling, hyperemia, and vascular injection. The edema zone has delineated boundaries. Pain is noted on palpation. Conducting biomicroscopy with "gelatinous" scleritis allows you to identify the zone of overhang of the chemosed conjunctiva over the limbus. This area has a red-brown hue and a gelatin-like consistency. On the surface of the cornea, infiltrates with pronounced vascularization can be found. The method of biomicroscopy with a slit lamp in diffuse scleritis determines the violation of the physiological radial direction of the vascular pattern. In the nodular form, visiometry indicates a decrease in visual acuity.

With purulent scleritis, external examination reveals a purulent infiltrate and vascular injection. The defeat of the posterior sclera is accompanied by swelling of the eyelids, conjunctiva and slight exophthalmos. The method of ophthalmoscopy determines the prominence of the optic nerve head, subretinal lipid exudation, detachment of the retina and choroid caused by the accumulation of exudate. Ultrasound in B-mode indicates thickening of the posterior part of the outer connective tissue membrane of the eyeball, accumulation of exudate in Tenon's space. Changes in scleral thickness can also be confirmed by CT.

With necrotizing scleritis, using fluorescein angiography, a tortuous course, areas of vascular occlusion, and avascular zones are determined. Conducting biomicroscopy with a slit lamp allows you to visualize necrotic changes in the sclera, ulceration of the adjacent conjunctiva. In the dynamics, an expansion of the necrosis zone is detected. The method of tonometry in patients with scleritis often reveals an increase in intraocular pressure (more than 20 mm Hg).

Treatment of scleritis

The treatment regimen for scleritis includes the topical use of glucocorticoid and antibacterial instillation drops. If the disease is accompanied by increased intraocular pressure, then the therapy complex must be supplemented with topical antihypertensive drugs. The course of treatment includes taking non-steroidal anti-inflammatory drugs. If they are intolerant, it is recommended to prescribe medications from the group of glucocorticosteroids. In scleritis without necrotic lesions, glucocorticoids and antibacterial drugs should be administered as subconjunctival injections. An alternative to this method of administration is the administration of prolonged forms of glucocorticoids.

With the development of scleral necrosis, combined therapy with glucocorticosteroids and immunosuppressants is indicated. In cases of an allergic reaction, antiallergic and desensitizing drugs are used in parallel with these drugs. With a purulent form of scleritis, treatment tactics are reduced to massive antibiotic therapy. In this case, oral and subconjunctival routes of administration of drugs from the group of fluoroquinolones, aminoglycosides and semi-synthetic penicillins are used. An additional method of administration is electrophoresis. In the absence of the effect of drug therapy, surgical opening of the abscess is indicated. Also, the treatment regimen should include drugs for the treatment of the underlying pathology, against which scleritis developed. If Mycobacterium tuberculosis is the etiological factor, topical anti-tuberculosis agents are considered as auxiliary.

Forecast and prevention of scleritis

Specific prevention of scleritis has not been developed. Non-specific preventive measures are reduced to the timely treatment of the underlying pathology, the prevention of inflammation of the paranasal sinuses (sinusitis), compliance with the rules of asepsis and antisepsis during surgical interventions. Patients with a history of systemic diseases should be examined by an ophthalmologist 2 times a year. The prognosis for life and working capacity depends on the timeliness of the diagnosis, the adequacy of treatment, the type of pathogen in case of an infectious lesion, and the form of the disease. The most favorable option is diffuse forms of the disease. For scleritis caused by Pseudomonas aeruginosa, an unfavorable prognosis is more often characteristic.

The human eye is a complex natural optical device through which 90 percent of the information for the brain enters. The sclera is a functional element of the organ of vision.

The condition of the shell indicates eye diseases, other pathologies of the body. In order to recognize the disease in time, one should understand what the sclera are.

The white of the eye consists of bundle-like, randomly arranged collagen fibers. This explains the opacity, different density of the fabric. The thickness of the shell varies between 0.3 - 1 mm; it is a capsule of fibrous tissue of an unequal thickness.

The white of the eye has a complex structure.

1. The outer layer is a loose tissue with an extensive vascular system, which is subdivided into a deep and superficial vascular network.
2. The sclera itself consists of collagen fibers and elastic tissues.
3. The deep layer (brown plate) is located between the outer layer and the choroid. Consists of connective tissue and pigment cells - chromatophores.

The posterior part of the eye capsule looks like a thin plate with a lattice structure.

Functions of the sclera

The fibers of the cover are arranged randomly, protect the eye from the penetration of sunlight, which ensures effective vision.

The sclera performs important physiological functions.

1. The eye muscles, which are responsible for the mobility of the eye, are attached to the tissues of the capsule.
2. The ethmoidal arteries of the back of the eyeball penetrate through the sclera.
3. A branch of the ophthalmic nerve approaches the eyeball through the capsule.
4. The tissue of the capsule serves as a sheath for the optic nerve.
5. Whirlpool veins exit the eye through the protein body, which provide the outflow of venous blood.

The protein shell, due to its dense and elastic structure, protects the eyeball from mechanical injuries, negative environmental factors. Protein serves as a framework for the muscular system, ligaments of the organ of vision.

What should the sclera of a healthy person look like?

The sclera is normally white with a bluish tint.

Due to the small thickness, the child has blue sclera, through which the pigment and the vascular layer shine through.

A change in color (dullness, yellowness) indicates disturbances in the body. The presence of yellowish areas on the surface of the protein indicates eye infections. A yellow tint can be a symptom of liver disorders, hepatitis. In infants, the covering is thinner and more elastic than in adults. Slightly blue sclera is normal at this age. In elderly people, the cover thickens, becomes yellow due to the deposition of fat cells, loose.

Blue sclera syndrome in humans is caused genetically or by a violation of the formation of the eyeball in the prenatal period.

Changing the type of protein is a justified reason for a visit to the doctor. The condition of the cover affects the functioning of the visual system. Diseases of the sclera are classified as congenital and acquired.

Congenital pathologies

Melanosis (melanopathy) is a congenital disease that is expressed by melanin pigmentation. Changes appear in the first year of life. The proteins of the child have a yellowish tint, pigmentation appears in the form of spots or stripes. The color of the spots may be gray or light purple. The cause of the anomaly is a violation of carbohydrate metabolism.

Blue sclera syndrome is often accompanied by other eye defects, anomalies of the musculoskeletal system, and the hearing aid. The deviation is innate. Blue sclera may indicate an iron deficiency in the blood.

Acquired diseases

Staphyloma - refers to acquired diseases. Manifested by thinning of the shell, protrusion. It is a consequence of eye diseases associated with destructive processes.

Episcleritis is an inflammation of the surface of the integument, accompanied by nodular seals around the cornea. Often resolves without treatment, may recur.

Scleritis is an inflammatory process affecting the inner layers of the scleral body, accompanied by pain. In the focus, a rupture of the eye capsule may form. The disease is accompanied by immunodeficiency, tissue edema.

Necrotizing scleritis - develops as a result of prolonged rheumatoid arthritis. It is manifested by thinning of the membrane, the formation of staphyloma.

Diseases of inflammatory origin can occur as a result of infections, disorders of the organs of the human body.

A timely visit to the doctor helps to identify diseases of the sclera in a timely manner, determine the cause and begin treatment.

ZrenieMed.ru

What is the sclera: structure, functions, diseases

December 16, 2016

The human eye is a unique organ that can perform many functions. It has a peculiar structure. However, not everyone knows what the sclera is and what diseases of this part of the eye exist. To begin with, it is worth understanding the structure of the eye.

What is sclera

The sclera of the eye is the outer shell of the eyeball, which has a large area and covers 5/6 of the entire surface of the visual organ. In fact, it is a dense and opaque fibrous tissue. The thickness and density of the sclera in some places is not the same. In this case, the range of changes in the first indicator of the outer shell can be 0.3-1 mm.

The outer layer of the sclera

So what is sclera? This is a kind of fibrous tissue, which consists of several layers. Moreover, each of them has its own characteristics. The outer layer is called the episcleral layer. There are a large number of blood vessels that provide high-quality blood supply to tissues. In addition, the outer layer is securely connected to the outer part of the eye capsule. This is its main feature.

Since the main part of the blood vessels passes to the anterior part of the visual organ through the muscles, the upper part of the outer layer differs from the internal parts in intensive blood supply.

Deeper layers

The sclera itself consists mainly of fibrocytes and collagen. These components are very important for the body as a whole. The first group of substances takes an active part in the process of producing collagen itself, as well as in the separation of its fibers. The inner, very last layer of tissue is called the "brown plate". It contains a large amount of pigment, which determines the specific shade of the eye shell.

Certain cells - chromatophores - are responsible for staining such a plate. They are contained in the inner layer in large quantities. The brown plate most often consists of a thin fiber of the sclera, as well as a slight admixture of the elastic component. Outside, this layer is covered with endothelium.

All blood vessels, as well as nerve endings located in the sclera, pass through emissaries - special channels.

What functions does

The functions of the sclera are very diverse. The first of them is due to the fact that collagen fibers inside the tissue are not arranged in a strict order. Because of this, the rays of light are simply unable to penetrate the sclera. This fabric protects the retina from intense exposure to light and sunlight. Thanks to this function, a person is able to see well. This is the main purpose of the sclera.

This fabric is designed to protect the eyes not only from intense lighting, but also from all kinds of damage, including those of a physical and chronic nature. In addition, the sclera protects the organs of vision from the effects of harmful environmental factors.

It is also worth highlighting another function of this fabric. Conventionally, it can be called a frame. It is the sclera that is a high-quality support and, at the same time, a reliable fastening element for the ligaments, muscles and other components of the eye.

congenital diseases

Despite the rather simple structure, there are certain diseases and pathologies of the sclera. Do not forget that this tissue performs important functions and in the event of any violations, the work of the visual apparatus as a whole deteriorates sharply. Diseases can reduce visual acuity and lead to irreparable consequences. Scleral ailments can be not only congenital, but also caused by various irritants and have an acquired character.

A pathology such as blue sclera often occurs as a result of a genetic predisposition and improper formation of tissues that connect the eyeball, even in the womb. The unusual shade is due to the small thickness of the layers. Through the thin sclera, the pigment of the shell of the eyes shines through. It is worth noting that such a pathology often occurs with other eye anomalies, as well as with violations of the processes of formation of the hearing organs, bone tissues and joints.

Diseases of the sclera are most often congenital. Melanosis is one of these. With the development of this disease, dark spots form on the surface of the sclera. Patients with a similar diagnosis should be registered with an ophthalmologist. With the development of such an ailment, regular monitoring is required, as well as timely prevention of the development of serious complications.

Acquired ailments

Quite often there is inflammation of the sclera. Diseases that arise as a result of such a process deserve special attention. The development of such ailments can provoke not only general violations of the functioning of certain systems of the human body, but also infections. Often, pathogens penetrate the tissues of the outer ocular membrane with the flow of lymph or blood. This is the main cause of the inflammatory process.

In conclusion

Now you know what the sclera is and what diseases of this tissue exist. The treatment of her ailments begins with the diagnosis and consultation of a doctor. Only a specialist can prescribe a therapy for the disease, identifying all the symptoms. With the development of ailments of the sclera, it is recommended to consult an ophthalmologist. The specialist must conduct a series of laboratory tests. After the diagnosis is made, therapy is prescribed.

If the disease is caused by a disorder in other body systems, then the treatment will be aimed at eliminating the underlying cause. Only after that, measures to restore vision will be carried out.

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What is the sclera and its functions

The sclera covers the outside of the eyeball. It refers to the fibrous membrane of the eye, which also includes the cornea. However, unlike the cornea, the sclera is an opaque tissue because the collagen fibers that form it are arranged randomly.

This is the first function of the sclera - providing high-quality vision, due to the fact that light rays cannot penetrate the tissue of the sclera, which would cause blindness. The main functions of the sclera are to protect the inner membranes of the eye from external damage and to support the structures and tissues of the eye located outside the eyeball: oculomotor muscles, ligaments, blood vessels, and nerves. Being a dense structure, the sclera, in addition, is involved in maintaining intraocular pressure and, in particular, the outflow of intraocular moisture, due to the presence of the Schlem's canal.

The structure of the sclera

The sclera is the outer dense opaque shell, which makes up most of the entire fibrous shell of the eyeball. It is approximately 5/6 of its area and has a thickness in various areas from 0.3 to 1.0 mm. The sclera has the smallest thickness in the region of the equator of the eye - 0.3-0.5 mm and the exit point of the optic nerve, where the inner layers of the sclera form the so-called cribriform plate, through which about 400 processes of retinal ganglion cells, the so-called axons, emerge.
In places of its thinning, the sclera is prone to protrusion - the formation of so-called staphylomas, or the formation of excavation of the optic disc, which is observed in glaucoma. With blunt injuries of the eyeball, scleral ruptures are also observed in places of thinning - most often between the sites of attachment of the oculomotor muscles.
The sclera performs the following important functions: skeleton - serves as a support for the inner and outer shells of the eyeball, the place of attachment of the oculomotor muscles and ligaments of the eyeball, as well as blood vessels and nerves; protection from external adverse influences; and since the sclera is an opaque tissue, it protects the retina from excessive external illumination, that is, lateral light, providing good vision.

The sclera consists of several layers: the episclera, that is, the outer layer, the sclera itself and the inner layer - the so-called brown plate.
The episcleral layer has a very good blood supply, and is also associated with the external rather dense tenon capsule of the eye. The anterior sections of the episclera are richest in blood flow, since the blood vessels pass to the anterior section of the eyeball in the thickness of the rectus oculomotor muscles.
The sclera tissue consists of dense collagen fibers, between them there are cells, the so-called fibrocytes, which produce collagen.
The inner layer of the sclera is externally described as a brown plate, as it contains a large number of pigment-containing cells - chromatophores.
Through the thickness of the sclera there are several through channels, the so-called emissaries, which are a kind of conductors for blood vessels and nerves entering or leaving the eyeball. On the anterior margin, on the inner side of the sclera, there is a circular groove, up to 0.8 mm wide. Its posterior protruding edge, the scleral spur, serves as the site of attachment of the ciliary body. The anterior edge of the groove is in contact with the Descemet's membrane of the cornea. Most of the groove is occupied by the trabecular diaphragm, and at the bottom is the Schlemm's canal.
Due to the structure, which is a connective tissue, the sclera is prone to the development of pathological processes that occur in systemic connective tissue diseases or collagenoses.

Methods for diagnosing diseases of the sclera

• Visual inspection.
• Biomicroscopy is a study under a microscope.
• Ultrasound diagnostics.

Congenital changes:

• Melanosis of the sclera.
• Congenital disorders of the collagen structure, for example, in Van der Heve disease.

Acquired Changes:

• Staphylomas of the sclera.
• Excavation of the optic disc is observed in glaucoma.
• Episcleritis and scleritis are inflammations of the sclera tissue.
• Scleral ruptures.

Causes, symptoms and treatment of scleritis of the eye

Scleritis is an inflammatory process that occurs in the sclera. The sclera or outer shell of the eye is called a dense white tissue, the function of which is to maintain the optimal shape of the eyeball. In addition, it is involved in the protection of the organs of vision from the ingress of pathogens. Photos of the sclera can be viewed on the Internet.

The disease is characterized by a chronic course. The patient has exacerbations and remissions. Pathology can occur first in one eye, and then move to the other. This disease is more often diagnosed in the fair sex at the age of 40-50 years.

Doctors distinguish the following types of illness:

• scleritis - inflammation covers all tissues of the sclera;
• episcleritis - only the outer layer is affected, which has a loose structure and is located under the tenon tissue.

Depending on the location of the inflammatory process, the following forms of the disease are distinguished:

• posterior form (occurs in the posterior tissues of the sclera of the eye);
• anterior form (diagnosed in the anterior tissues).

In addition, experts distinguish between nodular and diffuse forms. The first is a focus of inflammation or limited swelling. In the second form, extensive areas of the sclera are affected.

What are the causes of the pathological process:

• brucellosis;
• tuberculosis;
• various rheumatic processes;
• systemic lupus erythematosus;
• syphilis;
• adenovirus, herpes virus;
• various bacterial infections are the main causes of the disease;
• postoperative period (eyeball surgery);
• ankylosing spondylitis.

Pain syndrome, which can have a different degree. Sometimes it is a slight discomfort (the most common symptom) in the eyes. Some patients experience severe pain that radiates to the jaw system and temporal regions.

1. Pain is noted when moving the eyes.
2. Sensation of the presence of a foreign body in the cavity of the eye.
3. Periodic tearing.
4. When pressure is applied to the eyes, a person experiences pain.
5. Swelling and redness of the sclera, as well as the eyelids.
6. Visible dilated blood vessels in the eyes.
7. If there is tissue necrosis, then yellowish spots may be noticeable.
8. Protrusion of the eyeball (exophthalmos).

What complications can scleritis cause?

If the inflammation spreads to the cornea, then the person's vision will decrease and keratitis will occur. Symptoms at the same time indicate the presence of an advanced form of the disease. If the iris is involved in the process, then iridocyclitis is diagnosed. With suppuration, an abscess of scleral tissues develops.

Secondary glaucoma may result from damage to the trabecula or Schlemm's canal. When the sclera becomes thinner, staphylomas or protrusions occur. When the focus heals, a scar appears that deforms the eyeball. The result is astigmatism. If there is a deformation of the cornea, then it becomes cloudy, and vision is reduced. In some cases, the pathology threatens with edema and retinal detachment. Photos of possible complications are on the medical portals.

How is the diagnosis carried out

First, the ophthalmologist examines the patient's complaints, history and clinical picture. The following studies are being carried out:

• ophthalmoscopy and biomicroscopy;
• the composition of the lacrimal fluid is examined;
• magnetic resonance, optical and computed tomography;
• Ultrasound of the eyeball.

How is the treatment performed

Scleritis is treated for quite a long time, as it usually has a chronic form and gives numerous complications. Doctors use medication, which consists of taking antibiotics. Drugs are prescribed only after examination. If the cause was tuberculosis, then a chemotherapeutic method is used. In rheumatism and other systemic diseases, cytostatics, glucocorticosteroids are used. Scleritis is also treated with desensitizing, anti-inflammatory drugs and vitamins.

Physiotherapy treatment is indicated for those patients who do not have signs of an acute inflammatory process. These methods include electrophoresis, ultrasound, UHF. If the inflammation has gone too far, then they resort to surgical intervention. It is necessary for an abscess of the sclera. If the patient's tissue is severely thinned, then he is recommended to use a donor sclera transplant operation.

2 comments on the entry “Scleritis eyes”

1. Victoria 18.05.2015 16:05

Hello! Today my 9 year old son was diagnosed with acute scleritis, without much examination! How should an examination be carried out in general? Should any devices be used to establish such a diagnosis? And they immediately prescribed a bunch of drugs, without any tests?

valentine 10.11.2015 07:06

scleritis of the left eye for the third year in a row almost at the same time (in winter) How can this be cured?

leave a comment

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EyesExpert.ru

From the face of a person, you can learn a lot about his character, mood and even habits. Some of the symptoms of existing internal pathologies are also reflected here. Often, such signs can be noticed by looking closely at the eyes of the interlocutor and, in particular, at the state of proteins.

Symptom Definition

The outer (visible) part of the eye consists of the pupil (inner black circle), around which the iris (colored part) is located. Most often, the color of the eyes is determined by its color - brown, blue, gray. We perceive most of the eyeball in white if the eyes are healthy. Therefore, most often this part is called protein, although the medical term is sclera.

In total, the eyeball is covered with 3 shells: outer, middle and inner. The main role belongs to the outer shell, which is the most durable, supports the shape of the eyeball, and it is to it that the oculomotor muscles are attached. Therefore, any change in the color of the sclera, in particular its yellowing, is a signal of functional disorders not only in the eyes, but also, often, in the internal organs and systems.

Causes

A change in the color of the sclera of the eyes can affect the entire area of ​​\u200b\u200bthe eye or appear partially, in the form of yellowish spots. Sometimes such a symptom occurs gradually, and the patient does not attach much importance to the change in the color of the protein. Meanwhile, this is a very serious symptom, and most often it indicates the onset or development of a serious pathology in the body.

The most common causes of a change in the color of the sclera to yellow are:

• Liver problems. Most often, this phenomenon is due to a violation of the conjugation reaction with glucuronic acid, as a result, the output of bilirubin (a chemical pigment compound) is disturbed;
• Zhiroviki. As a result of a failure in lipid metabolism reactions, wen (pinguecula) may appear in the eye area, which can only be removed surgically, as well as to deal with another pathological condition - the growth of the conjunctiva;

Marked on the image is a pingvencula

Yellowing of the whites of the eyes, most often a sign of Botkin's disease, or jaundice. However, in isolated cases, this symptom may signal a more serious pathology, and should not be left unattended.

Possible diseases

The yellow color of the eye sclera is the result of an increased content of the yellow pigment (bilirubin) in the blood, which must be neutralized in the liver and excreted in the bile. However, if the metabolic processes in these organs are disturbed, the toxin remains in the blood or can even return there from the bile ducts.

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Retinal detachment: what is it this article will tell.

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A change in the color of proteins may indicate the progression of a number of pathological processes of internal organs:

• Liver diseases: hepatitis, cirrhosis, cancer, etc.;
• Blood diseases: malaria, babesiosis, poisoning with hemolytic poisons, etc.;
• Diseases of the biliary tract: Viral hepatitis, opisthorchiasis, etc.;
• Metabolic disease: hemochromatosis, amyloidosis, Gilbert's and Wilson-Konovalov's diseases, etc. With the development of pathological processes, the metabolism of proteins, metals or bilirubin is disturbed;
• Pancreatitis (any form). With inflammation of the pancreas, a blockage of the common bile duct occurs, as a result of which the penetration of direct bilirubin into the blood is also observed and, as a result, yellowing of the sclera of the eyes.

To start adequate treatment, a thorough diagnosis should be carried out, and not only the eyes, but also the internal organs. The main attention should be paid to the study of the functionality of the liver and pancreas.

Diagnostic methods

Diagnosing the cause of yellowing of the sclera of the eyes is quite difficult, since there are a lot of factors influencing this phenomenon. In the process of finding out, the doctor can use the most commonly used methods to determine the causes of the disease:

• Clinical: history taking and examination of the patient. In diseases of the liver, a common symptom is an increase in the size of the liver. Depending on the direction of the process, there may be a deterioration in the general condition, a decrease in efficiency, a disorder of the stool, etc. Severe symptoms are also observed in blood diseases: general malaise, high t, fever, tachycardia, and other signs of intoxication. If a change in the color of proteins occurs as a result of a metabolic failure or pathology in the bile ducts, then in this case the general condition of the body immediately worsens, signs of poisoning appear, the color of urine and feces changes, and seizures may occur. In pancreatitis, a characteristic symptom is, among other symptoms, pain in the middle part of the abdomen, which sometimes covers a circular area of ​​the body;
• Radiation: Ultrasound and CT of the abdomen. These techniques allow you to more accurately determine the localization of the pathological process in case of possible tumors or compression of the bile ducts. Sometimes these examination methods can only make a presumptive diagnosis, and for confirmation, a biopsy is performed - taking a sample of liver tissue using a special syringe for further laboratory tests;
• Laboratory research blood, feces and urine. With liver pathologies, the following changes may appear in the blood test: a decrease in the level of erythrocytes and hemoglobin, an increase in the content of bilirubin, cholesterol, etc.

When initial symptoms appear, you should contact your local general practitioner or family doctor, who, if necessary, can refer you for a consultation with a gastroenterologist or hematologist, ophthalmologist or oncologist.

Depending on the results of the studies, the doctor can draw up a scheme of therapeutic measures that are most effective for a particular pathology.

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Yellowing of the sclera of the eyes is most often a symptom of serious internal problems, so you should consult a doctor at the very beginning of the appearance of an alarming sign.

Prevention

As measures that reduce the risk of diseases provoking yellowing of the sclera of the eyes, it is necessary to pay increased attention to the recommendations for prevention:

• Compliance with a balanced diet, excluding alcohol, smoking, pickling, fried, flour (in large quantities);
• Sleep and rest regimen (sleep for at least 8 hours);
• Breaks while working at the computer and gymnastics for the eyes;
• Taking multivitamin complexes and special eye preparations.

The main preventive measure to prevent any diseases is taking care of the level of immunity, the main point of which is maintaining a healthy lifestyle.

Yellowing of the sclera of the eyes can be either completely harmless or a symptom of an incipient serious pathology. Therefore, when this symptom appears, you should not delay the visit to the doctor and wait for it to “resolve itself”, because in case of a disease, it can be localized at a very early stage.

And if you identify the causes of the most harmless nature, you can get rid of nervous tension from the unknown, which in itself will already have a beneficial effect on the state of general health.

Also read about strabismus in newborns in this article. It will also be useful to know whether it is possible to achieve effective treatment of cataracts with drops.

The sclera of the eye is the opaque outer layer of the eye. The sclera occupies the largest area of ​​the eye and has a dense composition. In different parts of the sclera of the eye has a different density. The thickness of the sclera also varies and ranges from 0.3 to 1 mm; in children it is very thin and increases with time. Describing the structure of the sclera of the eye, three layers are distinguished. This is the outer layer, that is, the episclera, the sclera itself and the brown plate or inner layer.

The structure of the sclera of the eye

The outer layer (Episclera) is well supplied with blood, the vascular network is divided into superficial and deep. The best blood supply occurs in the anterior sections, because the vessels approach the anterior section of the eye, located in the thickness of the rectus oculomotor muscles.

The sclera itself, like the cornea of ​​the eye, consists of collagen fibers, the space between which is occupied by fibrocytes that produce collagen.

The inner layer or brown plate - consists of thinned sclera fibers and elastic tissue. The fibers contain on their surface cells containing pigment - chromatophores. These cells give the inner surface of the sclera a brown tint.

The thickness of the sclera contains several through channels, which play the role of conductors for vessels and nerves, both incoming and out of the eye. The front edge of the inner side of the sclera has a so-called groove 0.8 mm in size. The ciliary body is attached to the posterior edge of the groove, and its anterior edge is adjacent to the Descemet's membrane. The main part of the groove is occupied by the trabecular diaphragm, above which is the Schlemm's canal.

Due to the fact that the sclera of the eye is a connective tissue, it is subject to the development of pathological processes that occur in systemic connective tissue diseases or collagenoses.

In those places where the sclera is thinned, protrusions (formations) may occur - the so-called staphylos. In addition, there may be an excavation (deepening) of the optic nerve, which is observed in glaucoma. Ruptures of the sclera also occur in its thin part, most often this occurs between the sites of attachment of the oculomotor muscles.

Functions of the sclera

- Protective;
- Support.

The main function of the sclera, of course, is protective - it protects the shells of the eye located inside from various external damage. Also, the sclera does not transmit light rays, which would lead to blindness, due to this, high-quality vision is achieved.

The sclera is a support for the tissues of the eye and its internal and external structures, which are located outside the eye - these are the vessels, nerves, ligaments, oculomotor muscles.

In addition, the sclera of the eye takes part in maintaining intraocular pressure, namely in the outflow through the Schlemm's canal.

Diagnostic methods for diseases of the sclera

- Visual inspection;
– Biomicroscopy – performed using a microscope;
- Ultrasound diagnostics.

Symptoms of diseases of the sclera

With congenital changes:

- Melanosis of the sclera;
- Violations of collagen structures - Van der Heve's disease.

Acquired changes in the sclera:

- Rupture of the sclera;
- Inflammation of the tissues of the sclera - Scleritis, episcleritis;
- Occurring in glaucoma - excavation of the optic nerve.

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Sclera - a dense opaque part of the fibrous (outer) shell of the eyeball (one sixth of the outer shell is the cornea - the transparent part).

The sclera of the eye consists of randomly arranged collagen fibers, providing its strong structure. Due to the fact that this shell is opaque, light rays are not able to penetrate through it to the retina. This protects the retina from being damaged by excessive amounts of light rays.

The sclera also provides a shaping function, being a support both for the tissues of the eyeball and for extraocular structures (vessels, nerves, ligamentous and muscular apparatus of the eye). In addition, this membrane is involved in the regulation of intraocular pressure (the Schlemm canal is located in its thickness, due to which the outflow of aqueous humor from the anterior chamber occurs).

Structure

The sclera in area is five-sixths of the fibrous membrane of the eyeball. In different parts, its thickness is 0.3-1 mm. The thinnest part is located in the region of the equator of the eye, as well as at the exit of the optic nerve, the cribriform plate, where many axons of retinal ganglion cells emerge. It is in these areas that protrusions - staphylomas, as well as excavation of the optic nerve head, can form with increased intraocular pressure. Such a process is observed in glaucoma.
With blunt eye injuries, ruptures of the sclera are most often formed in the area of ​​its thinning in the area of ​​fixation of the oculomotor muscles.

The main functions of the sclera:

• frame (support for the internal and external structures of the eyeball);
• protective (protects from adverse external influences, from excessive exposure of the retina to light rays);
• regulation of intraocular pressure (provides an outflow of aqueous humor).

The sclera consists of the following layers:

• episcleral - a layer rich in blood vessels associated with the outer dense capsule of the eye (Tenon's); the largest number of vessels is in the anterior sections, where the ciliary arteries pass from the thickness of the oculomotor muscles;
• directly scleral tissue - dense collagen fibers, between which fibrocytes are located, the processes of which form a kind of network;
• inner - brown plate, consisting of thinned fibers, as well as chromatophores - pigment-containing cells that give the appropriate color. This layer has practically no nerve endings and is poor in blood vessels.

In the thickness of the sclera are emissaries - channels through which arteries, veins and nerves pass to the choroid. Around the optic nerve are emissaries of the posterior short ciliary arteries, in the equatorial region - emissaries of the vorticose veins, in the anterior region - emissaries through which the anterior ciliary arteries pass.

A circular groove runs along the inner side of the sclera in the region of its anterior edge. The ciliary (ciliary) body is attached to its posterior protruding edge - the scleral spur, and its anterior edge borders on the descement membrane of the cornea. In the region of the bottom of the groove is the venous sinus - Schlemm's canal.

Since the sclera is a connective tissue rich in collagen fibers, it is subject to pathological processes inherent in collagenoses, systemic connective tissue diseases.

Video about the structure and functions of the sclera of the eye

Diagnosis of diseases of the sclera

Diagnosis of the state of the sclera is carried out using an external examination, ultrasound, and biomicroscopy.

Symptoms of diseases

• Change in the color of the sclera of the eye.
• The appearance of tissue defects.
• Spots on the sclera.
• Stretching and protrusion of the sclera of the eye.
• Changing the shape of the eyeball.