[Corneal extracellular matrix].

The paper analyzes the structural and functional state of the corneal extracellular matrix (ECM). It presents the currently available data on the role of connective tissue in health and during corneal pathological processes. Numerous morphological studies have provided evidence that the extracellular contact mechanisms characterized by extracellular and matrix-cell interactions are fundamental processes of corneal immunobiology.

[Morphological features of regenerative-reparative processes in the cornea exposed to synthetic analogues of endogenous peptide fragments of protein S100b in an experiment].

The effects of two 5-membered (SP5, SP6) endogenous synthetic peptide fragments of protein S100b on the course of regenerative-reparative processes in the corneas of Wistar rats were morphologically studied after making a graduated injury. Conjunctival or endonasal injection of the peptides was made at two concentrations of 10(-6) and 10(-8) M. The study peptides were found to have a modulating effect on regenerative-reparative processes regardless of the route of administration and to induce accelerated and qualitative corneal wound healing as compared with the controls. The specific feature of SP5 was the formation of a fibroblastic membrane. When SP5 was injected at a concentration of 10(-6) M, the membrane was more pronounced and occupied the whole area of keratectomy whereas when this peptide was administered at a concentration of 10(-8) M, its formation was observed in the deep and middle corneal layers. The most marked effect of SP6 revealed during the study was the formation of newly-formed vessels over the entire wound surface independently of the concentration of the injected substance. Of the two study peptide fragments, SP5 is, in the authors' opinion, promising for clinical application. Significant keratocytic proliferation noted in the use of SP5 at a concentration of 10(-6) M may be used to accelerate scarring when the sclera and cutaneous covering are damaged. The effects detected with administration of SP6 at two concentrations were regarded as negative as they did not answer the purpose set during the study performed.

[Pathomorphological changes in the photosensitized eye tissues after transscleral laser radiation: experimental studies].

The authors analyze the pathological changes occurring in the eye tissues after their prephotosensitization and transscleral laser radiation at a wavelength of 810 nm. These changes involve thrombosis of choroidal vessels, destructions of retinal photoreceptors and sclerocytes, and rupture of collagenous fibers of the deep layers of the sclera with its superficial layers being preserved. These changes were recorded just in the direct radiation area. Their magnitude, depth, and extent were directly correlated with the power of radiation and the diameter of a light splash. In the authors' opinion, the studies performed substantiate a transsceral approach for laser radiation in various abnormalities of the chorioretinal complex.

[Clinical and morphological characteristics of the scleral drainage area in normotensive glaucoma].

The ocular drainage system in normal intraocular-pressure glaucoma was studied by fluorescence lymphoangioscopy of the anterior ocular segment on 24 eyes and by histomorphological analysis of the drainage zone on 12 eyes. The study revealed the increased volumetric lymph flow in the drainage zone, which suggests the higher tissue drainage that correlates with intraocular pressure and agrees with the histomorphological findings. Patients with normotensive glaucoma were found to have ischemic and destructive changes in the drainage zone and vascular system of the anterior ocular segment. The histomorphological and lymphoangioscopic findings suggest the destruction of the drainage system, the retention of intraocular fluid, and the possible periodic unrecorded ophthalmic tone increase in normotensive glaucoma.

[Morphological rationale for autografting of musculus rectus ocularis fibers at revascular optic nerve decompression surgery].

The authors made a morphological study of the early proposed and clinically tested revascular optic nerve decompression operation developed to improve blood supply to the initial portion of the optic nerve in glaucoma-induced optic neuropathy. An experiment was carried out on 11 rabbits. The operated and control eyes were enucleated 1, 4, and 6 months after surgery. The experiment has established that muscle autografting into the retroscleral and paraneural space of the optic nerve is followed by a number of cellular reactions with the active participation of satellite cells, some of which may be associated with regenerative processes and presumably regarded as one of the cell autotherapy modalities.

[Spatial ultrasound visualization of the eye and orbit].

The paper presents data on the diagnostic use of three-dimensional (3-D) ultrasound visualization, analyzes earlier existing and new ultrasound diagnostic technologies, and shows it expedient to apply them in ophthalmologic practice. A hundred and forty-six healthy individuals and 52 patients (60 eyes) with different diseases of the eye and orbital cavity (chorioidal melanoma, facial angiomatosis, retinal detachment, vitreoretinal changes, etc.) were examined. The results of the studies and the analysis of the data available in the literature on this problem allow the authors to state that 3-D ultrasound diagnostic technologies can detect occult masses undetectable during conventional visual and ultrasound studies and define the topography of the dislocation of structurally complicated changes in the tunics of the eyeball.

[Comparative evaluation of the efficiency of transscleral diode laser cyclophotocoagulation during contact and contactless procedures: experimental morphological study].

To elucidate the extent to which contact and contactless procedures of diode laser transscleral cyclophotocoagulation (CPC) has a antihypertensive effect and a ocular tissue damaging effect, the authors have made a comparative assessment of the procedures to determine their preference. The study was conducted on an experimental material (5 Chinchilla rabbits (10 eyes)). The follow-up was 1 day to 6 months after laser interventions. The authors estimated the parameters of ocular hydrodynamics before and laser intervtntion throughout the follow-up and analyzed them with morphological changes kept in mind. The final antihypertensive effect of both contact and contactless procedures was virtually equal. However, less inflammatory changes and lower ocular damaging effect, and no additional medical manipulations for contactless diode laser CPC make it more preferable to contact CPC for clinical use.

[Results of a morphological study of the experimental use of polyglycolide fiber explants in the surgery of retinal detachment].

The paper presents the results of experimental use of a polyglycolide material-based filling for temporary episcleral filling in retinal detachment. Thorough comparative morphological and biomechanical studies of 120 experimental eyes in different periods after scleroplasty, by using an inflatable balloon catheter, homoscleral and polyglycolide fillings, have indicated that the polyglycolide filling material is completely lysed by ocular tissues within 60-90 days, which rules out a repeated surgical intervention for removal of temporary filling (for example, an inflatable balloon catheter), by preserving the constancy of the depth of scleral pressing-in. The short existence of a chemically indifferent polyglycolide filling in the ocular tissues excludes its negative effect on the surrounding structures of the eye, minimizes the likelihood of the occurrence of early postoperative complications, but thereby leading to a substantial increase in the biochemical stability of the scleral-and-chorioretinal complex in the early postoperative periods and ensuring increased resistance to dynamic loads, by forming a stable scleral-and-chorioretinal adhesion 3 months after surgery. The findings suggest that the designed polyglycolide explant has advantages and that it is expedient to introduce the new Russian resolving polyglycolide fiber explants into clinical practice (for scleroplastic operations).

[Results of a multi-year use of combined laser-surgical treatment in tumors of the epibulbar and limbocorneal localizations]. / Rezul'taty mnogoletnego opyta ispol'zovaniia kombinirovannogo lazerno-khirurgicheskogo lecheniia opukholei épibul'barnoí i limborogovichnoí lokalizatsii.

Fifty-five patients (55 eyes) were followed up. The "Romashka-2" CO2-laser plant was used for treatment of epithelial and epibulbar tumors (41 patients, 41 eyes). Microsurgical interventions with subsequent lamellar or penetrating keratoplasty were made in 14 patients (14 eyes). The experimental group of patients was followed up from 3 to 10 years. Relapses were registered in 4 eyes (4 patients). The CO2-laser treatment had a number of advantages before surgery or cryotreatment in removing the epibulbar tumors without growth in the cornea. Ablasticity, minimal trauma to tissues and evaporation of diffusive neoplasms can be named among such advantages. In cases of growth of epibulbar tumors in the cornea, there were direct indications for keratoplasty with preliminary barrage of CO2 irradiation on the sides of the mucous tunic of epibulbar tumor. Tumors were surgically removed with subsequent lamellar or penetrating keratoplasty being made with respect to a tumor type. The perfection of surgical technique consists in that one transplant of a bigger diameter is used instead of a corneoscleral transplant.

[An experimental-and-morphological substantiation of non-perforating profound sclerectomy with trabeculosuturization]. / Eksperimental'no-morfologicheskoe obosnovanie neperforiruiushchei glubokoi sklerektomii s trabekulosuturatsiei.

The causes of ineffectiveness of primary non-penetrating profound sclerectomy were analyzed on the basis of filtration-zone biopsy materials obtained in repeatedly made antiglaucomatous procedures. The authors believe that the above ineffectiveness is preconditioned by inconsistency of the drainage-zone internal wall resulting from its dystrophic changes due to tissue ischemia, cell apoptosis, collagen changes with fiber's degradation and fibers' colliquative necrosis. It was demonstrated experimentally that the monofilament suture, when applied to the filtration zone, enhances the hypotensive effect of the non-penetrating procedure due to the ability of filtration canals (shaping around sutures) to dose the outflow of lachrymal fluid through the anterior chamber into the subscleral and subconjunctival spaces as well as by activation of the uveoscleral outflow paths.

[2. Diagnostic resources and clinical indications]. / Soobshchenie 2. Diagnosticheskie vozmozhnosti i klinicheskie pokazaniia.

Preliminary investigations, dedicated to the diagnostic application of three-dimension ultrasonic angioreconstruction, confirmed the feasibility of using the above method in ophthalmologic practice in cases of suspected intraocular and orbital neoplasms. 32 patients (37 eyes) with various pathologies of the eye and orbital cavity, including choroidal melanoma, facial angiomatosis, retinal detachment, chronic uveitis etc.) were examined. The results are indicative of that the three-dimension ultrasonic angioreconstruction makes it possible to detect the latent vascular neoplasms, which cannot be defined by the standard visual and ultrasonic examinations, and the dislocation of structural elements of the eyeball tunics. Besides, it provides for evaluating their special localization and their interrelations with the neighboring anatomic elements.

[Lipid peroxidation in the pathogenesis of primary open-angle glaucoma]. / Perekisnoe okislenie lipidov v patogeneze pervichnoi otkrytougol'noi glaukomy.

19 tissue samplings of the iris and trabecula from 17 patients, aged 49 to 79, with primary open-angle glaucoma (POAG) of different stages were examined for the purpose of studying the condition of lipid membranes in the iridial and trabecular tissues by electron microscopy. The results are indicative of that the key role, in the POAG pathogenesis, belongs to lipid peroxidation of posterior and anterior leaves of the retinal pigment epithelium, which is an activator of apoptotic processes in the trabecular endothelium. Therefore, it is advisable to use the lipid- and water-soluble antioxidative drugs to correct the physiological antioxidative deficiency within a complex POAG treatment.

[Local senile ocular amyloidosis in the pathogenesis of open-angle glaucoma and pseudo-exfoliative syndrome]. / Lokal'nyi starcheskii amiloidoz glaza v patogeneze otkrytougol'noi glaukomy i psevdoéksfoliativnogo sindroma.

A total of 173 biopsy samples of the iris and drainage apparatus obtained at anti-glaucoma operations from 115 patients, aged 32 to 90, with primary open-angle glaucoma and pseudoexfoliative syndrome of different severity degrees were morphologically examined. Similar anatomofunction embryological peculiarities of the eye and brain create prerequisites for the development, in the eye, of processes analogical to Alzheimer's disease. Amyloid angiopathy of the iris is a key element of ischemia, which triggers the mechanisms of apoptosis and lipid peroxidation in the pigment epithelium membranes; this process is accompanied by an intensified synthesis and conformation of fibrous structures of tauprotein and beta-amyloid. Defradation of melanin and proteoglycans leads to the formation of neurotoxic metabolites. The above processes result in suppressing the protective antioxidant reactions as well as in blocking, by fibrous structures, the cellular cytoplasm and extracellular matrix.

[Key role of apoptosis in progressing uveal melanoma]. / Kliuchevaia rol' apoptoza v progressirovanii uveal'noi melanomy.

Apoptosis is known as a major achievement of biological world evolution aimed at eliminating "genetic waste," transformed or obsolete cells, and hence at controlling neoplastic processes. At the same time, clinical data point to an inverse effect. Thorough fundamental studies at the levels of light and electron microscopy allowed us to reveal several disturbances in physiological course of apoptosis. We discuss possible recruitment of this mechanism by tumor aimed at self-selection for a cell clone with maximum malignant potential and at elimination of less aggressive populations where the set of point mutations is abortive for further tumor progression.

[The causes of necrobiosis and apoptosis of corneal epithelial cells during primary acquired keratoconus]. / Prichiny nekrobioza i apoptoza épitelial'nykh kletok rogovitsy pri pervichnom priobretennom keratokonuse rogovitsy.

We studied 56 biopsy samples of conjunctiva and 50 corneal discs excised from 28 patients with acquired keratoconus cornea. The conjunctivas in all biopsy samples showed various stages of immune inflammation. Necrobiotic changes have been revealed in epithelium of the corneal discs going by the pathways of apoptosis--programmed cell death--and oncosis--initial edematic stage of necrobiosis. At the stage of acute inflammation they are due to cytotoxic effect of the lymphocytes, monocytes, and macrophages. Antibody-dependent cytotoxicity mediated by plasma and lymphoid cells predominates at this stage. At the reparative stage of inflammation ischemia, an inductor of apoptosis and oncosis, underlies necrobiotic changes in corneal epithelium.

[Experimental study of the effectiveness of the use of imunofan in the treatment of viral diseases of the eye]. / Eksperimental'noe issledovanie éffektivnosti primeneniia imunofana pri lechenii virusindutsirovannoi patologii glaz.

The efficiency of local therapy of ocular inflammations with a new drug immunophane was evaluated in experiments. Ophthalmological and morphological methods were used in the study. Experiments on 30 Wistar rats (60 eyes) demonstrated the absence of toxic effect on intact ocular tissues. Therapeutic efficiency of immunophane was demonstrated in 13 rabbits (26 eyes) with ophthalmic herpes. The advantages of subconjunctival injections of immunophane in comparison with instillations of leukocytic interferon are demonstrated.

[Cell-to-cell interactions between iris and trabecular meshwork in primary open-angle glaucoma]. / Kletochnye vzaimodeistviia raduzhnoi obolochki i trabekuliarnogo apparata glaza pri otkrytougol'noi glaukome.

Pathomorphological study of the ocular draining system in the presence of an ischemic iris was carried out in patients with primary open-angle glaucoma (POAG). A total of 173 biopsy specimens of the sclera and iris were collected during anti-glaucoma operations in 115 patients aged 32-90 years. The specimens were stained for amyloid with Congo red, thioflavin, and toluidine blue at pH 4.6 and 5.8 for detecting glycosaminoglycanes. The specimens were examined by histochemical and electron microscopic methods. Morphological changes in the trabecular system in POAG are due to abnormalities in the iridal microcirculatory bed. The status of the trabecular system during the initial and advanced stages of glaucoma depends on the severity of involvement of iridal arterioles, capillaries, and venules, modulating the biochemical processes in the anterior segment of the eye. Endotheliocyte and collagen matrix pathology and subsequent degradation of the trabecular system are closely related to dystrophic processes in the iris (release of plasma protein from the vessels and melanin granules into anterior chamber humor, cytotoxic effects of degradation products on adjacent tissues). The detected changes imply the use of drugs improving blood supply to the eye at the microcirculatory level and antihypoxants and antioxidants in local and total-systems therapy of patients with POAG.