Glaucoma – the chronic pathology of eyes which is characterized by increase in intraocular pressure, development of optical neuropathy and violations of visual function. Clinically glaucoma is shown by narrowing of fields of vision, pain, gripes and heavy feeling in eyes, a sight zatumanivaniye, deterioration in twilight sight, in hard cases a blindness. Diagnosis of glaucoma includes perimetry, a tonometriya and a tonografiya, a gonioskopiya, an optical coherent tomography, a laser retinotomografiya. Treatment of glaucoma demands use of antiglaukomny drops, application of methods of laser surgery (an iridotomiya (iridektomiya) and trabekuloplastik) or carrying out antiglaukomatozny operations (a trabekulektomiya, a sklerektomiya, an iridektomiya, an iridotsikloretraktion, etc.).
Glaucoma – one of the most terrible diseases of the eyes leading to sight loss. According to the available data, about 3% of the population have glaucoma, and at 15% of blind people in the world glaucoma served in everything as the blindness reason. In risk group on development of glaucoma there are people 40 years are more senior, however in ophthalmology such forms of a disease as juvenile and congenital glaucoma meet. Disease frequency considerably increases with age: so, congenital glaucoma is diagnosed for 1 of 10-20 thousand newborns; in group of 40-45-year-old people – in 0,1% of cases; at 50-60-year-old – in 1,5% of observations; after 75 years – more than in 3% of cases.
Understand the chronic disease of eyes proceeding with periodic or continuous increase in VGD (intraocular pressure), disorders of outflow of VGZh (intraocular liquid), trophic violations in a retina and an optic nerve that DON (disk of an optic nerve) is followed by development of defects of a field of vision and regional excavation as glaucoma. The concept "glaucoma" unite about 60 various diseases having the listed features today.
Reasons of development of glaucoma
Studying of mechanisms of development of glaucoma allows to speak about the multifactorial nature of a disease and a role of threshold effect in its emergence. That is developing of glaucoma requires existence of a number of factors which in the sum cause a disease.
The pathogenetic mechanism of glaucoma is connected with violation of outflow of the intraocular liquid playing a key role in a metabolism of all structures of an eye and maintenance of the VGD normal level. Normal the watery moisture produced by a ciliary (tsiliarny) body accumulates in the back camera of an eye – slit-like space, located behind an iris. 85-95% of VGZh through a pupil flow in the forward camera of an eye – space between an iris and a cornea. Outflow of intraocular liquid is provided with the special drainage system of an eye located in a corner of the forward camera both an educated trabecula and the shlemmovy channel (a venous sine skler). Through these structures of VGZh flows in skleralny veins. An insignificant part of watery moisture (5-15%) flows in the additional uveoskleralny way, filtering through a ciliary body and to a skler into venous collectors of a vascular cover.
For maintenance of normal VGD (
Development of congenital glaucoma is usually connected with anomalies of eyes at a fruit (disgenezy a corner of the forward camera), injuries, tumors of eyes. Predisposition to development of the acquired glaucoma is available for people with the burdened heredity on this disease, the persons having atherosclerosis and diabetes, an arterial hypertension, cervical osteochondrosis. Besides, secondary glaucoma can develop owing to other diseases of eyes: far-sightednesses, occlusions of the central vein of a retina, a cataract, a sklerit, a keratit, a uveit, an iridotsiklit, the progressing atrophy of an iris, a gemoftalm, wounds and burns of eyes, tumors, surgical interventions in the eyes.
Classification of glaucoma
By origin distinguish primary glaucoma as independent pathology of the forward camera of an eye, drainage system and DZN, and the secondary glaucoma which is a complication of extra-and intraocular violations.
According to the mechanism which is the cornerstone of increase in VGD allocate closed-angle and open-angle primary glaucoma. At closed-angle glaucoma the internal block in drainage system of an eye takes place; at an open-angle form – the corner of the forward camera is open, however outflow of VGZh is broken.
Depending on the VGD level glaucoma can proceed in normotenzivny option (with tonometric
On a current glaucoma can be stabilized (in the absence of negative dynamics within 6 months) and not stabilized (at a tendency to changes of a field of vision and DZN at repeated inspections).
On expressiveness of glaukomny process distinguish 4 stages:
- I (an initial stage of glaucoma) – are defined the paracentral scotomas, there is an expansion of an optical disk, excavation of DZN does not reach its edge.
- To II (a stage of the developed glaucoma) – the field of vision is changed in partsentralny department, also more is narrowed in a lower and/or verkhnevisochny segment on 10 °; excavation of DZN has regional character.
- III (a stage of far come glaucoma) – note concentric narrowing of borders of a field of vision, existence of regional subtotal excavation of DZN comes to light.
- IV (a terminal stage of glaucoma) – full loss of the central sight or safety of a svetooshchushcheniye takes place. The condition of DZN is characterized by total excavation, destruction of a neyroretinalny corbel and shift of a vascular bunch.
Depending on age of emergence allocate glaucoma congenital (at children up to 3 years), infantile (at children from 3rd to 10 years), juvenile (at persons aged from 11 up to 35 years) and glaucoma of adults (at persons is more senior than 35 years). Except congenital glaucoma, all other forms are acquired.
Clinical course of open-angle glaucoma, as a rule, asymptomatic. Narrowing of a field of vision develops gradually, sometimes progresses within several years therefore quite often patients incidentally find out that they see only one eye. Complaints to a look zatumanivaniye, existence of iridescent circles before eyes, a headache and an ache in nadbrovny area, decrease in sight in the dark are sometimes shown. At open glaucoma both eyes usually are surprised.
During a closed-angle form of a disease allocate a phase of a preglaukoma, a bad attack of glaucoma and chronic glaucoma.
Preglaukoma is characterized by lack of symptomatology and is defined at ophthalmologic inspection when the narrow or closed corner of the forward camera of an eye comes to light. At a preglaukoma patients can see iridescent circles on light, feel visual discomfort, short-term loss of sight.
The bad attack of closed-angle glaucoma is caused by full closing of a corner of the forward camera of an eye. VGD can reach at the same time
The bad attack of closed-angle glaucoma is medical emergency and demands the fastest, during several next few hours, decrease in VGD in the medicamentous or surgical way. Otherwise total irreversible loss of sight can threaten the patient.
Over time glaucoma accepts a chronic current and is characterized by VGD progressing increase, recidivous subbad attacks, increase of blockade of a corner of the forward camera of an eye. As an outcome of chronic glaucoma serves the glaukomny atrophy of an optic nerve and loss of visual function.
Diagnosis of glaucoma
Early detection of glaucoma has the important predictive value defining efficiency of treatment and a condition of visual function. The leading value in diagnosis of glaucoma plays definition of VGD, detailed studying of an eye bottom and DZN, a research of a field of vision, inspection of a corner of the forward camera of an eye.
As the main methods of measurement of intraocular pressure serves the tonometriya, an elastotonometriya, the daily tonometriya reflecting fluctuations of VGD within a day. Indicators of intraocular hydrodynamics decide on the help of an electronic tonografiya of an eye.
Integral part of inspection at glaucoma is the perimetry – delimitation of a field of vision by means of various techniques – izoptoperimetriya, kampimetriya, computer perimetry, etc. The perimetry allows to reveal even initial changes of fields of vision which are not noticed by the patient.
By means of a gonioskopiya at glaucoma the ophthalmologist has an opportunity to estimate a structure of a corner of the forward camera of an eye and a condition of a trabecula via which there is an outflow of VGZh. Ultrasonography of an eye helps to obtain informative data.
The condition of DZN is the most important criterion for evaluation of a stage of glaucoma. Therefore the complex of ophthalmologic inspection joins carrying out an oftalmoskopiya - the procedure of survey of an eye bottom. Deepening and expansion of a vascular funnel (excavation) of DZN is characteristic of glaucoma. In a stage of far come glaucoma regional excavation and change of color of a disk of an optic nerve is noted.
More exact qualitative and quantitative analysis of structural changes of DZN and retina is carried out by means of the laser scanning oftalmoskopiya, a laser polarimetry, an optical coherent tomography or the Heidelberg laser retinotomografiya.
Treatment of glaucoma
There are three main approaches to treatment of glaucoma: conservative (medicamentous), surgical and laser. The choice of medical tactics is defined by glaucoma type. As problems of drug treatment of glaucoma serve decrease in VGD, improvement of blood supply of intraocular department of an optic nerve, normalization of metabolism in eye tissues. Antiglaukomny drops on the action are divided into three big groups:
- The medicines improving outflow of VGZh: miotik (pilocarpine, ); simpatomimetik (); F2 prostaglandins an alpha – , ).
- The means inhibiting production of VGZh: selective and not selective ß-adrenoblokatory (, , , etc.); a-and β-adrenoblokator ().
- Medicines of the combined action.
At development of a bad attack of closed-angle glaucoma immediate decrease in VGD is required. Knocking over of a bad attack of glaucoma is begun with instillation of a miotik - 1% of solution of pilocarpine according to the scheme and solution of a timolol, purpose of diuretics (a diakarb, furosemide). Along with medicinal therapy hold the distracting events – statement of cans, mustard plasters, bloodsuckers on temporal area (girudoterapiya), hot foot bathtubs. Removal of the developed block and restoration of outflow of VGZh requires carrying out a laser iridektomiya (iridotomiya) or basal iridektomiya by a surgical method.
Methods of laser surgery of glaucoma are quite numerous. They differ with type of the used laser (argon, neodymium, diode, etc.), way of influence (coagulation, destruction), object of influence (an iris, a trabecula), indications to carrying out etc. In laser surgery of glaucoma the laser iridotomiya and an iridektomiya, a laser iridoplastika, a laser trabekuloplastika, a laser goniopunktura were widely adopted. At heavy degrees of glaucoma laser cyclocoagulation can be carried out.
Did not lose the relevance in ophthalmology and antiglaukomatozny operations. Among the fistuliziruyushchy (getting) glaucoma operations, the trabekulektomiya and a trabekulotomiya are most widespread. Carry not getting deep sklerektomiya to nefistuliziruyushchy interventions. Such operations as an iridotsikloretraktion, an iridektomiya, etc. are directed to normalization of circulation of VGZh. For the purpose of decrease in production of VGZh at glaucoma cyclocryocoagulation is carried out.
Forecast and prevention of glaucoma
It is necessary to understand that completely it is impossible to recover from glaucoma, however this disease can be kept under control. At an early stage of a disease when there were no irreversible changes yet, satisfactory functional results of treatment of glaucoma can be achieved. The uncontrolled course of glaucoma leads to irreversible loss of sight.
Prevention of glaucoma consists in regular surveys by the oculist of faces of risk groups - with the burdened somatic and ophthalmologic background, heredity, 40 years are more senior. The patients having glaucoma have to be on the dispensary account at the ophthalmologist, regularly each 2-3 months visit the expert, for life receive the recommended treatment.