Occlusion of the central vein of a retina
Occlusion of the central vein of a retina – the violation of a retinalny venous blood-groove caused by thrombosis of TsVS or its branches. Occlusion of the central vein of a retina is followed by sharp deterioration in sight of the affected eye what the periodic zatumanivaniye of sight, distortion of visibility of objects, dull aches in the depth of an eye-socket sometimes precedes to. The diagnostic algorithm at occlusion of the central vein of a retina includes carrying out a vizometriya, perimetry, a tonometriya, biomicroscopy, an oftalmoskopiya, the PHAGE, electrophysiological researches, a retina tomography. Treatment of occlusion of the central vein of a retina demands system introduction of trombolitik, vazodilatator, antiagregant; performing local and general hypotensive therapy; if necessary – rendering a surgical grant.
Occlusion of the central vein of a retina
Occlusion of the central artery and vein of a retina in ophthalmology is carried to number of vascular accidents, in view of precipitancy of their development and weight of consequences for visual function. Occlusion of the central vein of a retina develops at 214 people on 100 000 population, 65 years mainly are aged more senior. In the most part of cases (67,2%) passability of branches of TsVS, most often (82,4%) – a verkhnevisochny branch of the central vein of a retina is broken. Bilateral occlusion of the central vein of a retina occurs in 10% of observations, usually at patients with system diseases (atherosclerosis, arterial hypertension, diabetes, etc.).
Clinical classification of okklyuziruyushchy defeats of TsVS considers a stage and localization of process. In it allocate:
- Pretromboz of the central vein of a retina and its branches (nizhnevisochny, verkhnevisochny, nizhnenosovy, verkhnenosovy).
- Thrombosis (incomplete and full) TsVS and its branches with hypostasis or without hypostasis of a makulyarny zone.
- Posttrombotichesky retinopathy.
On weight of thrombosis of retinalny veins differentiate:
1. Occlusion of the central vein of a retina:
- ischemic (full) with neperfuziruyemy area of a retina of 10 diameters of DZN;
- not ischemic (incomplete).
2. Occlusion of branches of the central vein of a retina:
- the main branch of TsVS with an area of damage of a retina from 5 diameters of DZN;
- branches of the second order with an area of damage of a retina of 2-5 diameters of DZN;
- branches of the third order with an area of damage of a retina less than 2 diameters of DZN.
3. Gemitsentralny retinalny occlusion (ischemic and not ischemic).
Thrombosis of the central vein of a retina or its branches acts as the leading pathogenetic link of venous occlusion. The mechanism of a tromboobrazovaniye is caused by a compression of a venous vessel the central artery of a retina (usually in the field of an arteriovenozny recross or at the level of a trellised plate skler). It is followed by the turbulent current of blood and damage an endoteliya provoking formation of venous blood clot. This process is quite often accompanied by the arterial spasm causing violation of perfusion of a retina.
Venous stagnation is resulted by sharp increase in hydrostatic pressure in capillaries and venula of a retina that leads to sweating in okolososudisty space of plasma and cellular elements of blood. In turn, hypostasis even more aggravates a compression of capillaries, venous stagnation and a hypoxia of a retina.
Local and system processes can act as the reasons contributing to occlusion of the central artery of a retina. Among local factors the leading role belongs to eye hypertensia and primary open-angle glaucoma. Also the sdavleniye of vessels an orbit tumor, existence of hypostasis and the Druze of DZN, a tireoidny ophthalmopathy, etc. matters. Increases probability of venous occlusion periflebit retinas which quite often develops against the background of a sarkoidoz and Bekhchet's disease.
Carry a giperlipidemiya, obesity, an arterial hypertension, diabetes, the congenital and acquired trombofiliya, the increased viscosity of blood etc. to the system diseases associated with the increased risk of occlusion of the central vein of a retina.
It should be noted what develops in 50% of cases of occlusion of the central vein of a retina against the background of the available arterial hypertension or an oftalmogipertenziya.
Occlusion of the central vein of a retina is followed by sharp painless decrease in sight more often than one eye. Unlike occlusion of the central artery of a retina, at venous thrombosis falling of visual acuity happens not so promptly: usually this process develops within several hours or days (is more rare - weeks). Extent of deterioration in sight at not ischemic occlusion varies from moderated to expressed; at ischemic occlusion of the central vein of a retina sight falls to a slabovideniye or zero.
Sometimes it is preceded by episodes of a periodic zatumanivaniye of sight, the distorted vision of objects, emergence of a dark stain before eyes. Dull aches in an eye-socket cavity are in certain cases noted.
At gemiretinalny thrombosis or occlusion of branches of the central vein of a retina, except decrease in the central sight, the corresponding half or the sector of a field of vision suffers.
The diagnosis of occlusion of the central vein of a retina is made by the ophthalmologist taking into account data of the anamnesis, fizikalny and tool inspection, advisory opinions of the cardiologist, endocrinologist, rheumatologist, hematologist.
Serve as methods of objective diagnostics of occlusion of the central vein of a retina: visual acuity check, perimetry, tonometriya, biomicroscopy, oftalmoskopiya, angiography of vessels of a retina, electrophysiological researches.
In a stage of a pretromboz, and also at occlusion of branches of TsVS of the second and third order visual acuity decreases slightly or at all does not change. At not ischemic occlusion of the central vein of a retina and its branches the vizometriya reveals visual acuity higher than 0,1. Ischemic thrombosis of TsVS and temporal veins is followed by decrease in visual acuity lower than 0,1. The research of fields of vision finds the central or paracentral scotomas in the retina quadrants corresponding to defeat, concentric narrowing of fields of vision.
Tonometriya allows to reveal an oftalmogipertenziya; by means of a daily tonometriya of VGD it is estimated in dynamics. The changes revealed at biomicroscopy can be various: iris neovaskulyarization; relative afferent pupillary defect; existence of a suspension of elements of blood, exudate, floating clots of blood in a vitreous body, etc.
Signs, typical for occlusion of the central vein of a retina, are found by means of an oftalmoskopiya. Hypostasis of DZN and makula, gemorragiya in the form of "tongues of flame", an izvitost and moderate expansion of veins, their uneven caliber and microaneurisms, the velvet-like centers is characteristic. The Oftalmoskopichesky picture at defeats of various branches of TsVS has the features.
The fluorescent angiography of vessels reflects overdue contrasting of a retina, unevenness of contrasting of veins, lengthening of a phase of venous perfusion, granularity of a blood-groove. By results of angiograms judge prescription of thrombosis, localization and degree of occlusion of the central vein of a retina, development of a neovaskulyarization, a condition of a makula and DZN.
Elektroretinografiya reflecting retina ischemia degree allows to trace dynamics and to build the forecast concerning visual function.
From laboratory methods at occlusion of the central vein of a retina an essential role is played by a research of sugar of blood, a koagulogramma, definition of cholesterol and lipoproteid, folding factors.
Differential diagnostics of occlusion of the central vein of a retina is carried out with secondary retinopathies (hypertensive, atherosclerotic, diabetic, etc.).
treatment should be carried out only under the supervision of a doctor. Self-treatment is unacceptable!!!
In a sharp stage treatment of occlusion of the central vein of a retina is carried out in an ophthalmologic hospital; further – it is out-patient, under control of the oculist. At the first stage by means of intensive therapy retina traffic try to obtain restoration of a venous blood-groove, a rassasyvaniye of hemorrhages, reduction of hypostasis, improvement.
At a vein thrombosis of a retina intravitrealny injections of thrombolytic medicines (the fabric activator of a plazminogen, a prourokinaza, an urokinaza) are appointed subconjunctival, parabulbarny, sometimes. Both the general hypotensive and antioxidant therapy is carried out local (instillations of drops). Reception of antiagregant (aspirin), endotelioprotektor (), diuretic medicines is shown (, furosemide); introduction of vazodilatator (, ). At occlusion of the central vein of a retina introduction of trombolitik and vasodilating medicines through a catheter directly in TsVS branch is possible.
Application of surgical tactics is shown at makulyarny hypostasis and a neovaskulyarization. For this purpose use the laser coagulation of a retina (panretinalny, sectoral, preventive, etc.) allowing to close ischemic zones and to destroy neovascular complexes. At not resolving hemorrhages the vitrektomiya is carried out to a vitreous body.
Forecast and prevention
At not ischemic thrombosis of TsVS forecast in most cases favorable; gradual improvement and restoration of sight is noted. Ischemic occlusion of the central vein of a retina, as a rule, is complicated by posttrombotichesky neovascular glaucoma, recurrent hemorrhages in a vitreous body, a traction otsloyky retina, permanent falling of visual acuity.
Dispensary observation of the ophthalmologist with periodic control inspection (an oftalmoskopiya, biomicroscopy, a gonioskopiya, control of VGD) is shown to the patients who transferred occlusion of the central vein of a retina within half a year. It is necessary to exclude the factors promoting venous thrombosis, to carry out treatment of the accompanying pathology at experts of the corresponding profile.