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Purpose: to compare the effectiveness of conventional preserved amnion and amnion saturated with platelet-rich (PRP) plasma lysate for the treatment of persistent corneal erosions (PCE) after high-risk keratoplasty.Materials and methods. 40 patients with persistent corneal erosions after high-risk penetrating keratoplasty, followed up for 12 months, were divided into two clinical groups of 20 people each. The main group of patients, aged 34 to 84, received Flexamer amniotic membrane + PRP lysate, while the comparison group, aged 41 to 80, received Flexamer amniotic membrane only. Amniotic membrane coating was used in persistent corneal erosions of penetrating keratoplasty after unsuccessful conservative treatment. The amnion was sewn 2 mm from the limb with a continuous suture and covered with a soft contact lens. As a source of platelets, we used the blood of healthy volunteers, from which platelet-rich plasma with platelet concentration of over 1000 thousand/µl was taken, which was then frozen at -40 °C and defrosted at 0…4 °C to obtain PRP lysate. The criteria for evaluating the effectiveness of both groups were the times of epithelialization, the number of amniotic membrane coatings, and the number of preserved transplants at the end of the follow-up.Results. Lyophilized amniotic membrane saturated with autologous PRP lysate growth factors was shown to be biocompatible. It was found to be safe for the patients, to reduce the epithelialization time, to reduce the number of operations required to cover the PÑE with the amnion, and to increase the likelihood of successful transparent and translucent engraftment of a penetrating keratograft.Conclusion. The use of a lyophilized amniotic membrane enriched with growth factors of autologous PRP lysate is a promising method for the treatment of PCE of the penetrating corneal graft after high-risk keratoplasty.

Periodontal diseases is one of the most relevant and important problem in modern dentistry due to their increasing prevalence in population, association with the occurrence of focus of chronic infection, progressive development and irreversibility which, in case of severe damage of periodontal tissues, eventually leads to a loss of the number of teeth. All of the named factors eventually lead to the development of irreversible inflammatory-dystrophic and destructive changes in periodontal tissues. During the recent years the method of guided tissue regeneration that uses membranes is being successfully used for the treatment of periodontal diseases.A comparative study on the mandibular alveolar mucosa lesion healing during application of different types of biological matrixes containing decellularized amniotic membrane, decellularized amniotic membrane in combination with platelet-rich plasma (PRP) growth factors, and decellularized amniotic membrane in combination with PRP growth factors and hyaluronic acid was performed. The study proved the acceleration of the processes of wound area reduction. Under experimental conditions, the wound healing lasted from day 3 to day 5 of the study; however, the rate of reduction of the wound area was slower, which indicates an alterative stage of the acute inflammatory process. During days 5 – 7 (stage of regeneration, the 2nd phase of wound process) the wound area reduced rapidly and by day14 a complete epithelization of the surgical wound was observed in all groups using decellularized amniotic membrane. In the group using the combination of PRP growth factors and hyaluronic acid the epithelization of wound was already observed on the day5. In the control group healing occurres with scar formation.

Diabetes and related diseases are growing problem, which negatively affect populations around the world. According to experts, these indicators are expected to reach 7.7% or 439 million people by 2030. One of the main and serious complications of diabetes mellitus is diabetic foot ulcers. The analyzed studies have shown that wounds that penetrate the bones, recurrent wounds, wounds lasting more than 30 days, and wounds associated with peripheral vascular diseases are sources of risk of infection and subsequent amputation. The main clinical purpose of treating lower limb wounds is to heal quickly and completely, but even with the best care, these wounds often heal slowly, which requires specialists to find advanced treatments to reduce the risk of amputation. A significant part of the methods requires additional new therapeutic agents to remove the wound from the chronic inflammatory phase and heal it with normal epithelialization. This article discusses modern technologies for the treatment of diabetic foot ulcers using various products of the human amniotic membrane and bioengineered skin substitutes. Currently, there are more than 60 modern cellular and / or tissue drugs for the treatment of wounds, which makes it difficult to choose a suitable, safe and effective auxiliary therapy. According to various authors, the use of amniotic membrane products has demonstrated its high clinical effectiveness in comparison with standard therapy in the treatment of neurotrophic ulcers of the lower extremities in patients with diabetes mellitus.

Nowadays the development of novel biomaterials which would promote tissue lesions regeneration is one of the crucial tasks of regenerative medicine. In the current research we developed a biological active membrane composed of decellularized, lyophilized human amniotic membrane in combination with growth factors of platelet-rich plasma (PRP) and hyaluronic acid. On the basis of histological examination, scanning electron microscopic examination and DNA content analyses it was drawn a conclusion that Sodium Dodecyl Sulfate (SDS) (Sigma) solution and 1% Triton X-100 solution completely remove all existing cells of placenta and chorionic-amniotic membrane without impairment of their structure. After the processes of decellularization and lyophilization the DNA content was less than 2%. The PRP growth factors as the components biological matrix provide faster regeneration. The latter are fixed on the surface of cellular structure of decellularized, lyophilized human amniotic membrane by the reservoir of gelatinous hyaluronic acid

Limbal epithelial stem cells are localized in the limb, which determine the regeneration of the corneal epithelium, both physiological and reparative. The aim of the study is to characterize the culture of cells isolated by different methods.Materials and methods. Limbal stem cells were isolated from the limbus region of enucleated human eyes. Cell isolation was produced by the enzymatic and explantation methods. Cell cultivation was performed on the amniotic membrane and without it, in DMEM/F12 growth media (Dullbecco’s Modified Eagle Medium/Nutrient F12 Ham) and CECBM (Corneal Epithelial Cell Basal Medium). The morphological assessment and immunophenotyping of cell cultures were performed.Results and its discussion. The obtained culture was distinguished by cell heterogeneity at the enzymatic method of isolating cells from the limbus. The presence of fibroblast-like cells was revealed in the suspension of non-adherent cells, which resembled stromal cells in appearance and growth pattern. Immunophenotyping revealed that most cells carry markers of multipotent mesenchymal stromal cells (CD90+/CD73+/CD105+/CD34–/CD45–) and a small number – markers of epithelial cells (p63α+, ABCG2 +, CK19+). Explant culture was more uniform. The cells had a rounded, epithelial-like shape, adhered well to the surface of the amniotic membrane and grew on it. The results of phenotyping indicated that cells are represented mainly by epithelial cells (p63α+, ABCG2 +, CK19+).Conclusion. The culture is represented mainly by MMSC at the enzymatic method of isolating cells from the limbal graft and cultivating them without feeder in the growth medium DMEM/F12. Isolation of limb cells by the explantation method and their cultivation in the selective medium CECBM allow us to obtain mainly the culture of epithelial stem cells.

Objectives: This paper aims to examine the efficacy, safety, and long term outcomes of amniotic membrane transplantation for corneal surface reconstruction, in cases of limbal stem cell deficiency. Material and methods: A systematic literature search was performed on PubMed, for papers published up to February 2020, using the following combined search terms: "limbal stem cell deficiency", "amniotic membrane", "limbal transplant". Only clinical trials with human subjects were selected for analysis. We collected the data on amniotic membrane properties and mechanisms of action, processing, preservation and transplantation techniques, and clinical outcomes of different treatment methods. Results: The surgical approach for treating limbal stem cell deficiency depends on the extent of the disease. Isolated amniotic membrane transplantation appears to have a limited beneficial effect on limbal stem cells, whereas amniotic membrane transplantation, combined with certain types of limbal stem cell transplantation, provides long-term biological and mechanical support for the donor tissue explants. Combined with simple limbal epithelial transplantation, the amniotic membrane has shown excellent results in the surgical management of limbal stem cell deficiency. Conclusions: Preliminary results of amniotic membrane use in limbal transplantation show quite satisfactory data, but the lack of high-level randomized controlled studies makes it difficult to assess the comparative efficacy of amniotic membrane transplantation in limbal stem cell deficiency surgical management.

In numerous pathological processes of cornea the keratoplasty is often the only method of treatment. As different types of donor material are used in keratoplasty, this literature review is devoted to the application of preserved material and autotransplantation as the most available. The preservation methods of cornea allograft are divided into physical and chemical ones [Klement A.A., 1967]. According to the shelf-life all preservation methods are relatively divided into short and long termed. For the keratoplasty in some cases auto-tissues of a patient can be used. Autoconjuctiva has substantial advantages. Suhina L.A., Perekrestov M.B., Sukhina I.V. (2008) developed a therapeutic keratoplasty with autoscleral flap under conditions of traumatic injury of cornea. For reconstructive surgery amniotic membrane is applied, that is widely used recently in native and preserved form as a bio-cover for cornea, especially, in eye burns. Amnion tissue is an effective bio-stimulant of regenerative processes. After burns a special attention in the corneal epithelization is paid to limbus stem cells. In case of limbus-cellular insufficiency, stem cells, cultured on amniotic membrane, are used. Descemet’s membrane transplantation is the most modern technique of posterior corneal layer transplantation. This technique has become very important in corneal EED. Layer-by-layer keratoplasty with the «Alloplant» biomaterial is suggested as an effective method of treatment for deep trophic corneal ulcers. In penetrating states of cornea the optimization method of temporary filling technique using corneal and scleral tissues or silicone rubber to close penetrating defects during keratoplasty. Kasparov A.A., Aladinskaya I.V., Trufanov S.V. proposed in patients with vascularized corneal spots to sew during keratoplasty an umbilical part of amniotic membrane to the limbus region around keratotransplant. Different types of keratoplasty are presented above where different types of donor material are used. The correct choice can predetermine beneficial outcomes (optic, tectonic, therapeutic, cosmetic) of surgical treatment.

Purpose. To evaluate long-term results of intrastromal amniotic membrane implantation in patients with induced endothelial epithelial dystrophy (EED) of cornea. Material and methods. The clinical study included 50 patients (50 eyes) with a diagnosis of secondary corneal EED of the far-advanced stage. All patients underwent the surgery of intrastromal implantation of amniotic membrane (IIAM) in the cornea.Results. The obtained data in the course of the study showed a slight, statistically significant increase of visual acuity in the operated patients. On admission of patients the visual acuity averaged 0.01±0.005, 24 months after the IIAM – 0.03±0.01 (p

ABSTRACT In numerous pathological processes of cornea the keratoplasty is often the only method of treatment. As different types of donor material are used in keratoplasty, this literature review is devoted to the application of preserved material and autotransplantation as the most available. The preservation methods of cornea allograft are divided into physical and chemical ones [Klement A.A., 1967]. According to the shelf-life all preservation methods are relatively divided into short and long termed. For the keratoplasty in some cases auto-tissues of a patient can be used. Autoconjuctiva has substantial advantages. Suhina L.A., Perekrestov M.B., Sukhina I.V. (2008) developed a therapeutic keratoplasty with autoscleral flap under conditions of traumatic injury of cornea. For reconstructive surgery amniotic membrane is applied, that is widely used recently in native and preserved form as a bio-cover for cornea, especially, in eye burns. Amnion tissue is an effective bio-stimulant of regenerative processes. After burns a special attention in the corneal epithelization is paid to limbus stem cells. In case of limbus-cellular insufficiency, stem cells, cultured on amniotic membrane, are used. Descemet’s membrane transplantation is the most modern technique of posterior corneal layer transplantation. This technique has become very important in corneal EED. Layer-by-layer keratoplasty with the «Alloplant» biomaterial is suggested as an effective method of treatment for deep trophic corneal ulcers. In penetrating states of cornea the optimization method of temporary filling technique using corneal and scleral tissues or silicone rubber to close penetrating defects during keratoplasty. Kasparov A.A., Aladinskaya I.V., Trufanov S.V. proposed in patients with vascularized corneal spots to sew during keratoplasty an umbilical part of amniotic membrane to the limbus region around keratotransplant. Different types of keratoplasty are presented above where different types of donor material are used. The correct choice can predetermine beneficial outcomes (optic, tectonic, therapeutic, cosmetic) of surgical treatment.

Reconstruction of the conjunctiva is required for restoration of damaged ocular surface and is an essential part of that process. Traumas, chemical and thermal burns, multiple surgical intervention can seriously damage the integrity of conjunctival tissue and promote the growth of fibrous tissue, scarring of contractures and their shortening, as well as other complications such as trichiasis, erosion and ulcers on the cornea. When a larger area is affected, there may not be enough donor tissue to replace the defect, in which case the tissue grafts are required to be large enough. Modern modifications of surgical techniques and the continued development of tissue engineering, as well as advancements in stem cell research offer promising novel alternatives for solution of those problems. This article reviews the existing surgical methods of conjunctival reconstruction.

The article reviews the main properties of the cornea and the mechanisms of its physiological regeneration and repair in response to damage and describes the most promising methods of treatment aimed at stimulating limbal stem cells and based on the use of native tissues of perinatal origin, umbilical cord mesenchymal stromal cells, and cell-free therapeutic products.

Infectious keratitis is one of the most common causes of blindness worldwide. Despite the existence of a wide arsenal of quite effective antimicrobial drugs, some forms of bacterial and viral keratitis are resistant. Advanced acanthamoeba and mycotic lesions of the cornea, as well as mixed forms of infection usually do not respond well to conservative treatment. In the absence of positive dynamics from the applied etiotropic therapy with observed further progression of the microbial process, there is a risk of corneal perforation and spread of infection to the sclera or deep ocular structures with a high probability of irreversible functional disorders or anatomical death of the eye. In such cases, a timely transition to surgical treatment is necessary in order to maintain structural integrity of the eyeball. For this purpose, corneal crosslinking, microdiathermocoagulation, tissue adhesive, autoconjunctival plasty, amniotic membrane, corneoscleral flap coating, various combinations of these methods, as well as therapeutic keratoplasty are used most often in clinical practice. The choice depends on the etiology, size and depth of the lesion, its localization, prognosis of visual outcomes, somatic status of the patient. Therapeutic keratoplasty is the most radical and effective method of surgical intervention that allows eradication of the infectious focus and best possible restoration of the structural integrity of the eyeball. However, in some cases due to inaccessibility of donor material or high risks of the surgery and non-transparent graft engraftment, it is advised to use alternative surgical approaches, and keratoplasty, if necessary, should be carried out for optical purposes at a further, "quiet" period.

Pterygium is one of the modern problems of ophthalmology. The exact etiology and pathogenesis of this disease has not been reliably established and, as a result, there is no universal method for its recurrence-free treatment. The literature data on various methods of pterygium surgical treatment such as 'bare sclera', conjunctival autograft, limbal stem cells transplantation techniques, amniotic membrane plasty and other methods was analyzed. The advantages and disadvantages of those surgery methods were identified. With consideration of the new data on proliferative nature of the disease, the results of adjuvant treatment of pterygium using cytostatics and anti-VEGF drugs were examined. Introduction of new technologies for the treatment of pterygium in practical health care can significantly improve the effectiveness of surgeries, reduce the incidence of postoperative complications and the number of relapses of the disease.