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Neurology, Ophthalmology, Cardiology, Oncology, Obesity, Endocrinology, Vascular surgery - Causes, Symptoms, Diagnosis, Treatment, description of the disease.

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Monday, 10.08.2020, 19:35
Main » Ophthalmology » Glaucoma causes 
18:21
Glaucoma causes


Glaucoma causes

Glaucoma is a disease that occurs due to violations of hydrodynamics eye (intraocular fluid motion). When glaucoma occurs periodically or permanently increased intraocular pressure. Under the influence of elevated intraocular pressure narrowed field of vision, reduced central vision, there is atrophy of the optic nerve. Outcome of the disease is blindness. It is believed that one in five blind patient lost his vision due to glaucoma.


Glaucoma can occur immediately or shortly after birth. If the child is not in time to surgical treatment, there may be complete loss of vision for 2-3 weeks. In adult glaucoma develops after age 40. The incidence of glaucoma in adults 1-1.5 cases per 100 people.


Intraocular pressure value and a relatively constant rate in it is from 9 to 22 mm Hg. of Art. During the day the intraocular pressure can vary by 2-6 mm. Typically, the higher it is in the morning, increases during blinking is reduced during sleep. Intraocular pressure provides resistance membranes of the eyes and the development of intraocular fluid.

Intraocular fluid or aqueous humor produced by the ciliary body processes. Function of intraocular fluid except to maintain the intraocular pressure in the diet are the lens and cornea, which have no blood vessels. As part of the intraocular fluid contains chloride, lactic and ascorbic acid, a very small amount of protein.

If production of intraocular fluid is reduced, there is hypotension eyes. Cause of reduced production of aqueous humor may be inflammation of the choroid of eyes (uveitis, iridocyclitis), diabetic coma, uremic coma, with a sharp and prolonged reduction in blood pressure. Long-existing eye hypotension may reduce the size of the eye and its atrophy.

Increased production of intraocular fluid leads to an increase in intraocular pressure. However, this is rare. Increased intraocular fluid pressure occurs usually due to violations of the outflow. After the development of intraocular fluid processes of ciliary body, it goes to the rear chamber of the eye, which is located between the lens and iris. Fluid through the pupil moves into the anterior chamber, which is limited to the cornea in front, behind the iris and lens.

Outflow of intraocular fluid occurs in the anterior chamber of the eye where the cornea and sclera border is the angle of the anterior chamber. In the transition region of the cornea to the sclera is deepening - Schlemm's canal. The entrance to the canal is covered by a fold of connective tissue called trabeculae. Under pressure trabecula bend in the channel and through it into Schlemm's canal is filtered intraocular fluid. Over the channel is shlemmovym outgrowth scleral shell - spur. To spur attached iris and ciliary muscle. In a normal outflow of intraocular fluid occurs in Schlemm's canal and then into the venous system.

Glaucoma can be:
primary
the secondary one.

Primary glaucoma occur when anomalies of the angle of the anterior chamber.

When violations of intraocular fluid within the eye, often at the root of the iris, angle-closure glaucoma occurs. In this way the outflow of intraocular fluid overlain by internal structures of the eye. Typically, angle-closure glaucoma occurs in the eyes of a small size, and hyperopia (farsightedness). This creates prerequisites for anatomical closure glaucoma: a small depth of the anterior chamber, the shift of all the structures of the eye forward. With the increasing size of the lens age, anterior chamber depth decreases and the age of forty may be glaucoma.

Sometimes the inner block may be due to the condition of the pupil. If the lens is tightly pressed to the iris, the outflow from the back of the camera is broken, the pressure in it increases. The iris bulges forward under pressure and it covers the root path of the outflow, intraocular pressure increased.

Embarrassment can be caused by the outflow of the iris seal, which with age becomes less elastic. At the root of the iris folds are formed, which cover ways of intraocular fluid. In this case, the patient has complaints of pain in his eyes mist in low light. When looking at the light, the pupil narrows, the iris expands, the folds are straightened and the complaints disappeared.

At the siege of intraocular fluid in connection with the displacement of the lens and its infringement in the ring of ciliary body malignant glaucoma occurs. This gives rise to a persistent increase in intraocular pressure and eye drops rapidly. Require urgent surgery.

When the outdoor unit liquid outflow at shlemmova channel - there is a open-angle glaucoma. Violation of the outflow of fluid at the level shlemmova channel occurs at anomalies of development and attachment of the ciliary muscle, scleral spur development anomalies, anomalies of the trabeculae. Sometimes, when eating disorders eyes occurs wash the pigment of the choroid, which, falling in the intraocular fluid accumulates in the trabeculae and disrupts its function.

Moreover, in the eyes of various diseases with eating disorders and metabolic processes in the eye during intraocular fluid may contain various inclusions that close the gap and cause a violation of the trabeculae of intraocular fluid.



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