[Bioprinting technologies in ophthalmology]. / Tekhnologii biopechati v oftal'mologii.

Bioprinting allows additive fabrication of bioengineered constructs with defined two- or three-dimensional organization using live cells, biopolymers and other materials. This article reviews main bioprinting technologies and their capabilities in clinical and experimental ophthalmology. Analysis of literature sources helped reveal and describe the main types of bioprinting technologies: inkjet, laser-assisted, and extrusion. Extrusion bioprinting is the most widely used method, providing the ability to use various types of bioinks and a wide range of cell concentrations. The following materials can be used as the base for bioinks: alginate, collagen, gelatin, hyaluronic acid, chitosan, fibrin, as well as their different combinations. These materials can be modified for best bioprinting properties by adding various functional groups. The major directions of application of bioprinting technologies in ophthalmology are tissue engineering for regenerative medicine and fabrication of model systems for fundamental and preclinical studies. Experiments in creating a bioprinted cornea are being conducted in the field of regenerative medicine. Furthermore, there are studies on fabricating retinal tissue equivalents, although tissue engineering of this structure is a task of great complexity. Model systems, which can be fabricated by bioprinting, are represented by tissue equivalents of ocular structures and the appendages of the eye, as well as by microphysiological organ-on-a-chip systems. Another promising application of bioprinting is fabrication of biocompatible implantable electrode arrays for visual neuroprostheses.

The Chick Embryo and Its Structures as a Model System for Experimental Ophthalmology.

The possibilities of using the chick embryo and its individual structures as a model system in experimental ophthalmology are considered. Cultures of the retina and spinal ganglia from chick embryos are used in the development of new methods for the treatment of glaucomatous optic neuropathy and ischemic optic neuropathy. The chorioallantoic membrane is used for modelling vascular pathologies of the eye, screening of anti-VEGF drugs, and assessing biocompatibility of implants. Co-culturing of chick embryo nervous tissue and human corneal cells makes it possible to study the processes of corneal reinnervation. The use of chick embryo cells and tissues in the "organ-on-a-chip" system opens up wide opportunities for fundamental and applied ophthalmological studies.

[Therapeutic hygiene of eyelids in dry eye disease prior to cataract phacoemulsification]. / Terapevticheskaya gigiena vek pri sindrome «sukhogo glaza¼ pered provedeniem fakoemul'sifikatsii katarakty.

PURPOSE: The study evaluates the effectiveness of eyelid hygiene (EH) in correction of the ocular surface (OS) condition in patients with dry eye disease (DED) ahead of cataract phacoemulsification (CPE). MATERIAL AND METHODS: The study included 90 patients with cataract: the first group consisted of 45 DED patients with lipid deficiency, the second group - 45 DED patients with lipid/mucous deficiency. Prior to CPE, all patients were randomized into three subgroups of 15 people each. In subgroups 1.1 and 2.1 patients did not receive any treatment for correction of the state of ocular surface. Patients in subgroups 1.2 and 1.3 were instilled 0.18% sodium hyaluronate (SH); in subgroups 2.2 and 2.3 - fixed combination of 0.15% SH and 3% trehalose. In subgroups 1.3 and 2.3 EH was performed (with «Blefarogel cleansing¼, «Blefarolotion¼, «Blefarogel-1¼ two times a day for one month before CPE). The control points were: 1) at study inclusion; 2) after correction of the ocular surface condition; 3) 30 days after CPE. The following parameters were evaluated: OSDI, TBUT (Norn's test), severity of meibomian gland dysfunction (MGD), patient satisfaction with CPE (CPE-PS). Statistical analysis: M±SD calculation, Mann--Whitney, Kruskal-Wallis and Wilcoxon tests. RESULTS: At the second control point, a statistically significant more pronounced OSDI decrease and bigger increase in TBUT were observed in subgroups 1.3 and 2.3 compared to subgroups 1.2 and 2.2 (Mann-Whitney U-test). Apparently, this was associated with a reduction in MGD severity in patients who received EH. At the third control point, significant lower values of OSDI and MGD severity, higher TBUT values and greater CFE-PS were recorded in subgroups 1.3 and 2.3 (Kruskal-Wallis test, Wilcoxon two-sample test). CONCLUSION: Carrying out EH using the «Blefarogel cleansing¼, «Blefarolotion¼, «Blefarogel-1¼ and artificial tear in patients with DED and cataract can increase the efficiency of correction of ocular surface condition and improve patient satisfaction with the outcome of CPE.

[Application of the organ-on-a-chip technology in experimental ophthalmology]. / Primenenie tekhnologii «organ-na-chipe¼ v eksperimental'noi oftal'mologii.

Organ-on-chip is a microfluidic device that can reproduce in vitro the minimal functional unit of an organ or system of organs and model various physiological processes and body structures with high accuracy. This review covers the main approaches to the use of the organ-on-chip technology in modern experimental ophthalmology. The analysis of literature sources revealed the following main applications of the organ-on-chip technology in ophthalmology; the technology allows modeling the anterior eye surface and its diseases, such as dry eye syndrome, as well as disorders of the posterior segment of the eye such as age-related macular degeneration, diabetic macular edema, diabetic retinopathy, glaucoma. Culturing of eye tissues in microfluidic systems helps identify the toxic effects and pharmacological activity of new compounds, and provides an opportunity for deeper understanding of the normal physiology of the eye and the pathogenesis of ocular diseases. In addition, the technology can reduce the cost and duration of experiments. Thus, the organ-on-a-chip technology has a great potential in the field of experimental ophthalmology and preclinical trials of new ophthalmic drugs.

[Modern concepts of bionic vision]. / Sovremennye kontseptsii bionicheskogo zreniya.

Loss of vision is a pressing medical and social problem leading to profound disability, loss of ability to work, serious alterations in the psycho-emotional state, and a decline of the quality of life. When conservative or surgical treatment can not help restore vision, the use of visual prosthesis - bionic eye - can be an effective solution. This review covers the main modern approaches to the development of visual prosthetic systems. Analysis of publications revealed that there are several main approaches to visual prosthesis differing primarily by the anatomical structure targeted for stimulation in order to activate visual sensations. The most significant among them are retinal prostheses, optic nerve stimulation, and cortical visual prostheses. Currently, retinal prostheses such as ARGUS II demonstrate the most successful results, since the stimulation of the surviving neural structures of the retina is a relatively easy task, but their field of application is limited to diseases associated with pathological changes in photoreceptors. The development of cortical visual prostheses is more difficult, but in the future they may allow using more stimulation channels to obtain a more detailed visual perception. In addition, cortical visual prostheses are universal, as they do not require preservation of any structures of the visual organ, only the primary visual cortex.

[The impact of material and human resources on the availability of cataract treatment (simulation example)]. / Vliyanie material'nykh i kadrovykh resursov na dostupnost' lecheniya katarakty (primer modelirovaniya).

The World Health Organization recommends monitoring the trends and assessing the progress of ophthalmic care focused on the actual needs of people. To solve these problems, the authors of this paper have proposed and tested an analytical model, named «Cataract¼, which on the one hand can help evaluate the needs of the population in terms of cataract treatment, and on the other - assist with analysis of the available resources to meet these needs. The model can help identify the bottlenecks and predict the required resources, as well as assess the degree of satisfaction of the population's needs with the current and projected amount of medical care. This model allows analyzing, planning or predicting the resources of healthcare facilities needed for the treatment of cataracts while simultaneously assessing its impact in order to meet the medical needs of patients with cataracts.

[Ocular surface changes after cataract phacoemulsification]. / Izmeneniya glaznoi poverkhnosti posle fakoemul'sifikatsii.

PURPOSE: To assess the effects of phacoemulsification cataract surgery (PCS) and its pharmacological support on the prevalence of dry eye (DE) type ocular surface changes. MATERIAL AND METHODS: The study included 550 patients with age-related (369 patients) or complicated (181 patients) cataracts (247 men, 303 women; mean age 71.6±7.3 years) who were assessed using the Ocular Surface Disease Index (OSDI), tear break-up test (TBUT), Shirmer-1 test, lipid interference test, OCT meniscometry, examined for xerosis indicators and «lid vipers¼ symptom in order to detect DE before PCS, as well as on days 1, 7, 30 after PCS. Meibomian gland dysfunction (MGD) was determined by the Norn compression test, which was performed before PCS. The significance of differences was assessed using Pearson χ2 test. RESULTS: Before PCS the prevalence of DE was 51.1%, asymptomatic subclinical DE - 28.9%. MGD was detected in 79.4% of DE patients and in 50.3% subclinical DE patients. After PCS, an increase in DE prevalence was noted (due to increase in the prevalence of mild DE): on the 1st day - up to 58% (χ2=5.295; p=0.022; p<0.05), on the 7th day after surgery - up to 63.1% (χ2=16.165; p=0.001; p<0.01), on the 30th day - up to 55.6% (χ2=2.283; p=0.131; p>0.05). CONCLUSION: The study revealed a trend towards an increase in DE prevalence after PCS (due to an increase in the proportion of hypersecretory mild DE), which was statistically significant on days 1 and 7 after the operation and statistically insignificant by the 30th day after surgery. Apparently, it could be associated with aggravation of "background" asymptomatic ocular surface changes. From our point of view, the high prevalence of DE and subclinical DE in cataract patients before PCS makes it advisable to carry out preoperative preparation aimed at normalizing the condition of ocular surface. At the same time, the high prevalence of MGD in DE and subclinical DE patients determines one of the directions of preoperative treatment - eyelids hygiene.

[Eyelid hygiene in preparing dry eye patients for cataract surgical treatment]. / Gigiena vek v podgotovke patsientov s sindromom «sukhogo glaza¼ k operativnomu lecheniyu katarakty.

PURPOSE: To evaluate the effectiveness of complex treatment, including eyelid hygiene, on the condition of ocular surface in dry eye patients before cataract surgery. MATERIAL AND METHODS: The study included 56 female age-related cataract patients (64±4.3 years old) with dry eye caused by Meibomian gland dysfunction (MGD). The main group patients (n=28) underwent eyelid hygiene therapy (2 times a day, 1 month) that involved Blefarogel cleansing, Blefarolotion, Blefarogel-1. The main and control (n=28) group patients performed (during the month): «fat-water¼ type nanoemulsion instillation (3 times a day); preservative free vitamin-A application (at night). Methods included dry eye symptoms assessment (OSDI scale); TBUT; Shirmer-1 test; lissamine green vital staining with xerosis indicator calculation (van Bijsterveld scale); "lid wipers" symptom evaluation; Norn compression test. Statistical evaluation included: mean and standard deviation calculation (M±s); significance of differences assessment (Mann-Whitney U-test; Wilcoxon's T-test). RESULTS: The main group patients (artificial tear, keratoprotection, eyelid hygiene) showed a statistically significant more pronounced decrease in OSDI (from 33.2±3.1 points to 15.2±1.8 points) and a significantly more pronounced increase in TBUT (from 4.8±0.5 s to 6.9±0.4 s) than in control group patients (artificial tear, keratoprotection; respectively, from 32.7±3.2 to 20.8±3.1 points and from 4.85±0.5 to 5.8±0.4 s; p<0.05). Apparently, this was associated with a significantly more pronounced relief of the MGD signs in main group patients (from 2.1±0.1 to 1.1±0.2 points; p<0.05) as a result of eyelid hygiene. In the control group, the dynamics of MGD severity (from 2.08±0.3 to 2.11±0.5 points) was statistically insignificant. CONCLUSION: Eyelid hygiene (based on Blefarogel cleansing, Blefarolotion, Blefarogel-1) increases the effectiveness of dry eye treatment in MGD patients, compared with isolated tear substitution and keratoprotection.

[The Dynamics and Prognosis of Glaucoma and Cataract Morbidity in Urban Areas of the Krasnodar Kray].

The analysis of dynamics of glaucoma and cataract morbidity of adult population in metropolises of Krasnodar Kray in 2012-2016 established the most negative trend in glaucoma morbidity, especially in Sochi. The prognosis of glaucoma morbidity in Sochi testifies its increasing in 2017-2019. The cataract morbidity in the explored cities has more favorable dynamics. Armavir is the problematic metropolis on cataract morbidity that is also confirmed by prognosis results. The study results are to be applied in activities of ophthalmologic service specialists when developing territorial curative preventive programs.

[The diagnostic and prognostication of glaucoma.]

The glaucoma is a leading cause of irreversible blindness in all countries. In the nearest years an increasing of patients with the given pathology is prognosticated. Nowadays, development of disease is related to alteration of interleukin profile in lacrimal fluid. however, diagnostic significance of interleukins is studied insufficiently. The purpose of study. To determine diagnostic significance of interleukins on a local level for amelioration of diagnostic and prognostication of development of glaucoma. The content of interleukins in lacrimal fluid was analyzed in 80 patients with glaucoma stage II and 45 healthy individuals using technique of sandwich-linked enzyme-linked immunosorbent assay with calculation of informativeness of indices of immunity. The results. The analysis established high diagnostic significance of IL-2, IL-17, IL-8 for verification of glaucoma. They are proposed to be applied in laboratory diagnostic and prognostication of disease. The developed regression model ensures with high accuracy prognostication of development of glaucoma in case of increased level of IL-2, IL-17, IL-8.

[Eye lid hygiene in chronic allergic blepharoconjunctivitis patients before laser refractive surgery]. / Gigiena vek v podgotovke k lazernoi refraktsionnoi khirurgii.

AIM: To evaluate the effectiveness of eyelid hygiene in patients with chronic allergic blepharoconjunctivitis (ABC) as a part of their preparation for laser refractive surgery. MATERIAL AND METHODS: The study involved 32 patients (12 males and 20 females aged 25-42 years) with refractive errors, namely, compound myopic astigmatism (23 patients) and hyperopic astigmatism (9 patients) suffering from chronic ABC and secondary dry eye syndrome (DES). All the patients initially received a standard treatment for ABC and DES, that is olopatodin hydrochloride instillations - 1 mg/ml 2 times daily, preservative-free hyaluronic acid preparation - 1 mg/ml 3 times daily, and polyacrylic acid and dexpanthenol gel at night for one month. The scheme, however, appeared not effective enough. Hence, the patients were prescribed eyelid hygiene (Blepharolotion or Blepharosalfetka plus Blepharogel-1 2 times daily) to relive meibomian gland dysfunction (MGD). They also underwent a conventional ophthalmic examination, allergy tests, evaluation of ABC and DES signs and symptoms, tear film break-up time test, Schirmer's test, meibomian glands evaluation, optical coherence tomography with meniscometry, xerosis index evaluation, and lissamine green staining for lid wiper epitheliopathy. RESULTS: At the beginning of the study signs and symptoms of MGD-associated DES were predominant in all patients. Chronic ABC signs were mild. In 2-3 months, meibomian gland function and tear film break-up time improved significantly in most patients, while xerosis index decreased and lid wiper epitheliopathy resolved. Laser refractive surgery (LASIK) was performed in 81.25% of patients, all of whom were satisfied with the results. CONCLUSION: Inclusion of eyelid hygiene into preoperative management of patients with chronic ABC and DES allows to achieve optimum conditions for laser refractive surgery in most cases.

[Treatment of chronic allergic blepharoconjunctivitis].

OBJECTIVE: to evaluate the effectiveness of therapeutic eyelid hygiene in the treatment of chronic, or perennial, allergic blepharoconjunctivitis (ABC). MATERIAL AND METHODS: A total of 30 patients with chronic ABC (11 men, 19 women aged 25-41 years; disease duration 2-4 years) were examined before and after a treatment course which included instillations of olopatodine hydrochloride instillations (1 mg/ml, 2 times daily) and hyaluronic acid (2 mg/ml, 3-4 times daily). Patients from the main group (18 patients, 36 eyes) additionally practiced therapeutic eyelid hygiene using Blepharoshampoo, Blepharolotion or Blepharosalfetka, and Blepharogel-1 (2 times daily). The control group was given only anti-allergic therapy and tear substitutes. Conventional ophthalmological examination, allergy testing, ABC signs and symptoms evaluation, Schirmer's 1 and Norn's tests, tear film break-up time evaluation, assessment of meibomian gland function, optical coherence tomography (OCT) for tear meniscus, xerosis index evaluation and lissamine green staining for lid wiper epitheliopathy, and anterior segment photography with further computer morphometry were performed in all patients. RESULTS: Dry eye signs and symptoms, including combined lipid, water, and mucus tear deficiency, were found in all patients with chronic ABC. Patients from the main group demonstrated a significantly greater decrease of integral indices of subjective ocular discomfort, reduction of chronic ABC signs as well as more pronounced improvement of the meibomian gland function, appearance of the lid wiper region, tear film break-up time, results of the OCT-meniscometry, and xerosis index. CONCLUSION: Introduction of therapeutic eyelid hygiene to the complex treatment of chronic allergic blepharoconjunctivitis with the aim of resolving secondary dry eye symptoms enhances the effectiveness of the treatment.

[Natural physical factors of the Kuban' Black Sea coastal area in the rehabilitative treatment of children with psoriasis and concomitant ophthalmoherpes].

The primary objective of this study was to optimize the process of remedial treatment at health reports of Sochi, Gelendzhik, and Anapa by introducing sun, air, and sea water baths in the system of sanatorium-and-spa treatment of the children with various nosologic forms of psoriasis and concomitant ophthalmoherpes that necessitated keratoplastic surgery. The study included children at the age of 7-13 years with plaque and nummular psoriasis vulgaris who received rehabilitative treatment after keratoplasty for ophthalmoherpes. The children were randomly allocated to two groups. One comprised patients based at the specialized children's sanatoria "Yunost", "Vulan", and "Bimlyuk" (Roszdrav) (group 1, n = 278). Patients of the control group were given conventional treatment in municipal outpatient settings in compliance with the existing standards (group 2, n = 278). The study showed a 2.39-fold decrease of the psoriasis area and severity index (PASI) in the children of group 1 compared with its 1.38-fold decrease in group 2. It is concluded that a combination of natural physical factors of the Kuban' Black Sea coastal area has highly beneficial effect on the outcome of postoperative treatment of children with plaque and nummular psoriasis vulgaris and concomitant ophthalmoherpes responsible for corneal ulceration that requires corrective keratoplastic surgery.

[A new method for microdrainage using a porous titanium nickelide endoprosthesis in resurgery of uncompensated glaucoma].

Experimental (23 rabbits) and clinical (42 patients with operated glaucoma) studies were conducted to evaluate the effect of a titanium nickelide implant on ocular tissue in modified deep sclerectomy in order to normalize intraocular pressure. Scleral morphological studies in the area of implant placement revealed the formation of a capsule with "fissures" and vessels. Clinically, there was intraocular pressure compensation in 92.8% of the patients operated on.

[Eye surgical aid to patients with diabetes mellitus in the Krasnodar Branch of the state institution "Eye Microsurgery" Intersectonal Scientific-and-TechnoIogical Complex].

The setting up of a vitreoretinal surgery department "Eye Diabetes" and the introduction of the basic rates of medical officers into the structure of an anesthesiological department have increased the flow of patients referred for surgical treatment at the expense of patients with diabetes mellitus (DM). The charges for purchase of diagnostic equipment and medicines, those for additional rates of medical officers are compensated for by the increased activity. The active treatment-and-prevention tactics allows detection of DM, preoperative correction without hospitalization to a speciailized hospital, by reducing the time of preoperative preparation. By taking into account the experience in working with patients with DM and their great need for eye surgical aid, the authors consider it necessary to develop an endocrinological service in future and to set up new medical surgical centers of this specialty.