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Purpose. The key to understanding the development of any vitreoretinal pathology is a presence of a clear conception to possible variants of changes in the anatomical and topographic relationships of the posterior cortical layers of the vitreous body and the retinal internal limiting membrane (ILM) in a formation of posterior vitreous detachment (PVD).An original method of macro-microscopic examinations of anatomical objects proposed by professor V.P. Vorobyov, which includes investigations of morphological objects whose dimensions lie in the boundary area between macroscopic parameters studied by anatomists and microstructures studied by histologists, discover a new boundary area for the study of anatom ical structures.However, it has not been practically used in ophthalmology until now. The study of a process for changes in the vitreoretinal interface during the PVD occurrence is difficult due to a complexity of simulation, a possibility of visualization, and an absence of approved protocols for macro-microscopic research.Purpose. To study variants of anatomical and topographical changes in the vitreoretinal interface during the formation of induced PVD in ex vivo experiments using the method of macro-microscopic examination.Material and methods. The study was performed in 24 eyeballs of cadaver donors. To assess changes in the vitreoretinal interface in the process of PVD induction, an original method of dissection was used, that allows to isolate layer-by-layer the cortical layers of the vitreous body and the retinal ILM, with a possibility of further evaluation of changes in the vitreoretinal interface by the macro-microscopic examination. Salt barium sulfate suspension Video-contrast was used with the purpose to contrast vitreous fibers. Macroscopic investigation was carried out using the Topcon OMS-800 operating microscope with an indication from x8 to x21 magnification, microscopic changes were evaluated by the light microscopy method with x50, x100, x200, x400 x630 magnification using the Leica DM LB2 microscope with the subsequent photo r egistration.Results. During the macro-microscopic study, three variants of possible changes in the vitreoretinal interface during the development of induced PVD were revealed, which were interpreted as the normal (true) PVD and abnormal PVD, which occurred both with the formation (the variant A) of vitreoschisis zones (exfoliation of the cortical layers of the vitreous body) and with the zones of retinal ILM exfoliation (the variant B).Conclusion. The proposed method of macro-microscopic investigation of the vitreoretinal interface allows to dissect isolated sequentially layerby- layer the cortical layers of the vitreous body and the retinal ILM with subsequent fixation on a special substrate according to the original method and the possibility to carry out a histological section and its evaluation by the light m icroscopy method. The application of the developed method allows to accurately assess changes in the vitreoretinal interface on any isolated site of the vitreoretinal surface. The presented work demonstrates possibilities for the application of the method to detect variants of changes in the vitreoretinal interface within the formation of i nduced PVD.

Purpose. To assess the results of a comparative internal limiting membrane (ILM) staining with vital dye ≪Membrane blue dual≫ and suspension ≪Vitreocontrast≫ in patients with idiopathic macular holes using the computer colorimetry.Material and methods. The study included 15 patients with idiopathic macular holes ≥400 μm which underwent the three-port 25 Gauge vitrectomy, ILM peeling using the ≪inverted flap≫ technique followed by air tamponade. In all cases, the macular region was divided provisionally into 2 equal parts, ILM within the first part was stained with ≪Vitreocontrast≫ suspension, the second one with Membrane Blue Dual dye. After video recording of the intervention, a comparative assessment of agents staining ability was carried out using the computer colorimetry.Results. In a comparative colorimetric analysis, the average Euclidean distance CIELAB MembraneBlue® Dual between the stained ILM and the corresponding region of ILM-free retina was 15.97±7.4, for ≪Vitreocontrast≫ suspension 22.87±6.67. The average Euclidean distance CIELAB for ≪Vitreocontrast≫ suspension was significantly higher according to t-test than the average Euclidean distance for MembraneBlue® Dual dye at p=0.012. A revealed higher Euclidan distance for ILM, stained with ≪Vitreocontrast≫ suspension, suggests that when using this agent, the surgeon’s eye perception of ILM staining intensity will be objectively higher than with MembraneBlue® Dual solution.Conclusion. ≪Vitreocontrast≫ suspension provides a more vividly perceived staining of ILM for the surgeon`s eye than MembraneBlue® Dual, effectively and instantly settling both on the membrane itself and on possible epiretinal membranes on its surface. It does not loose adhesion throughout the entire surgical procedure. Thus, the suspension ≪Vitrerocontrast≫ can be recommended as an alternative to existing agents for ILM staining.

Introduction. The vitreous body (VB) is limited by anterior cortex (AC) layers, consisting of densely interconnected collagen fibers. There is no consensus regarding the structural AC organization and its relationship with the structures of the eyeball.Purpose. To study the anatomical and topographical features of the anterior cortical layers of VB.Material and methods. We developed an original method for contrasting the VB structures using an ultra-fine Vitreokontrast suspension based on a water-insoluble inorganic salt of barium sulfate in the isotonic solution. The study was performed in 20 cadaveric donor eyes. the original technology. Dissection was carried out according to a proposed original technology. The scleral incision was made at a 4mm distance from the limbus along the circumference. Then we cut the sclera between the rectus muscles, then the petals of choroid and retina were formed, and also they were cut off. Then we cut the sclera between the rectus muscles, then the petals of choroid and retina were formed, and also cut them off. We stained the vitreous structures using the Vitreokontrast suspension with a sequential removal of the anterior cortex up to the posterior lens capsule.Results. After the cortex removal in the cadaveric donor eyes several membranous structures (on an average of four) were detected with a covering the retrolental space with an ability to exfoliate, with sites of the attachment to the Wieger ligament and fibers of ciliary zonula and pars plana. After the removal of the membranous structures and their restaining a layer of vitreous fibers was contrasted on the posterior capsule of the lens in the area of Berger space projection. Conclusion. The study revealed no case of a true full anterior cortex detachment. The anterior cortex exfoliation occurred with the formation of a multilayer membranous structure, covering the posterior surface of lens and ciliary body.The presence of vitreous fibers closely associated with the posterior capsule of the lens in the projection area of Berger space, allows to suppose a possibility of retrolental bag existence, one of walls of which is associated with the posterior lens capsule.

Purpose. To evaluate clinical morphological characteristics or iris-ciliary zone in patients with secondary posttraumatic aniridic glaucoma.Material and methods. The study included 43 patients (43 eyes) aged 18-62 years with secondary posttraumatic aniridic glaucoma: after open globe injury – 32 eyes and contusion trauma – 11 eyes; primary surgical debridement was performed at the place of residence. Associated pathology: traumatic cataract – 15 patients, aphakia – 28 patients. Time after trauma was 5-9 years. All patients underwent reconstructive surgeries, including iris-lens diaphragm implantation and deep sclerectomy with hydrogel drainage implantation. The follow-up period was 18 months. The standard ophthalmologic examination and the additional ultrasound bio-microscopy were performed in preand post-operative period. Fragments of sclera were excised intra-operatively during the opticoreconstructive surgery with deep sclerectomy in 3 patients and were studied in histological examination.Results. The performed complex morphological studies revealed the continuation of fibroplastic processes at all levels of aqueous humor outflow despite the long period after trauma (5-9 years). According to the ultrasound biomicroscopy data in vivo, there was a sclerotic deformation of ciliary body and its processes, collapse of trabecular meshwork with locuses of its occlusion with iris root. However, according to the histopathologacal data, cicatrization process was not completed, the evidence of this was a fibroplastic cell reaction with neo-vascular invasion. Probably, this contributes to the block of neo-formed intra-scleral outflow pathways. All this can explain unstable results after surgery for secondary glaucoma in eyes with aniridia.Conclusion. The found features of iris-ciliary zone should be taken into consideration during the reconstructive and glaucoma surgery in patients with secondary aniridic glaucoma. The revealed factor of uncompleted fibroplastic process with a moderate active cell and vessel proliferation needs a further study to increase the efficacy of prevention and treatment in such group of patents.

Purpose. To develop a new method of vitreous body (VB) preparation with the isolate contrasting and separation of the VB structures (canals, cisterns, and their anastomosis).Material and methods. The research was performed in 20 cadaver donor eyes. The preparation of vitreous body was performed as follows. The circle-wise cutting of sclera was carried out in a 4mm distance from the limbus. The anterior segment of the eye was intact. Then we cut sclera between the rectus muscles, forming scleral tabs except the optic nerve disk and macular area (10-11mm in diameter). The tabs were cut off. Then we formed the choroidal and retinal tabs using the blade and anatomical forceps and cut off them too. We used the Vitreocontrast suspension dyeing for a VB structures contrasting. After it we cut the VB cortex, separated the dyed vitreous body structures, and performed the light microscopy examination.Results. We developed a new method of vitreous body preparation with the intact anterior segment and the area in the posterior pole (10-11mm in diameter), equatorially (15-17mm), in the tab cisterns (8-10mm) in the 21.5-23.5mm axial length of the eye. There was not found any integrity or structural disruption, rupture of vitreous during the preparation. The Vitreokontrast suspension has a high adhesion to the structural elements of vitreous body and allows to separate and to isolate the vitreous body structures (canals, cisterns and their anastomosis). The light microscopy examination showed the presence of canals and cisterns walls. This structures are differ from the vitreous matrix.Conclusion. The new method of VB preparation with a maximum maintenance of its structures (intact anterior segment and a site of posterior pole in diameter of 10-11mm) and the new Vitreocontrast dye allow to contrast all vitreous body structures separately. The analysis of this data will allows to detect the pathological changes of the vitreous, to determine its role in developing of vitreoretinal diseases.

Purpose. To develop a new method of intraocular drug delivery to the posterior segment of the eye using a new biodegradable multilayer sustained-release implant.Material and methods. We fabricated a multilayer biodegradable intravitreal implant, which has a tube form, 4.0mm length and 0.3mm diameter, that is composed of polyvinylpyrrolidone, lactic acid and glycosaminoglycans. Implant consists of 15 layers with the thickness of each layer 10μm. Layers are connected by transverse septums. The degradation time of the implant depends on a transverse septum quantity. The intravitreal empty implant was placed in 5ml of 0.9% NaCl solution in a closed vial at 37° C (5 implants). The replacement of 3.0ml of balanced salt solution (BSS) with the maintenance of the specified temperature and volume was made once a day. Measurements of the implant time resorption were carried out from the beginning of the experiment to the full visual disappearance of the implant in the test-tube.Results. The full resorption time of the empty implant was 31 days. The presence of water leads to hydrolysis of the implant polymer matrix. The degradation rate depends on the quantity of cross-linking between the layers of the implant and can be changed variably. Scanning electron microscopy has shown the laminated structure of the implant, presence of the transverse septums between each layer. In the developed delivery system the drug is uniformly distributed in each of saturated layer. The release of drug substance from the implant occurs as a result of polymer degradation and diffusion of the substance into the surrounding fluid.Conclusion. The implant for drug delivery to the posterior segment of the eye is developed, it allows to prolong the stay of drugs in the vitreous cavity. The new fabricated biodegradable multilayer intravitreal implant provides periodical release of active agent without its therapeutic concentration overdose.