Optimum | Tangible Hydra-PEG™ – Gaining Momentum in the Industry

The issue of hydrophilicity of the surface of gas permeable contact lenses remains one of the persistent problems. Tangible Hydra-PEG™ surface coating is applied to gas permeable contact lenses to significantly improve wettability and wearing comfort. Although it is mainly used to alleviate dry eye symptoms in scleral and corneal lens users, particularly for those patients with corneal ectasia and/or Ocular Surface Disease (OSD), it can be used in other modalities. This article describes the development of the product and describes the benefits of its use in a clinical case.

A Clinical Case of Fitting Scleral Lens for Correction of Pellucid Marginal Degeneration

Background. Pellucid Marginal Degeneration (PMD) is a rare bilateral degenerative corneal disease. It causes corneal ectasia with bilateral, clear, inferior (typically 4 o’clock to 8 o’clock), peripheral corneal thinning. It usually affects about 80% of corneal stroma, which leads to the corneal ectasia above the thinning area as well as provokes the irregular astigmatism and visual impairment that are difficult to correct. Purpose. To study the possibilities of correction and social rehabilitation in a patient with PMD wearing scleral lenses. Materials and methods. The study included a patient with PMD, signs of corneal dysfunction and narrow-angle subcompensated glaucoma in the right eye, and PMD of the cornea resulted in a corneal leukoma – terminal glaucoma in the left eye. In addition to standard ophthalmic methods, we performed corneal topography and optical coherence tomography (OCT). For intraocular pressure measurement, ICARE IOP tonometer was used in several areas of the intact peripheral cornea. Results. Prior to lens fitting, UCVA in the right eye amounted to 0.06. Scleral lens helped achieve a high visual acuity of 0.9–1.0. The lens was well-tolerated by the patient. Conclusion. Scleral lenses may be a good choice for patients with irregular cornea caused by corneal dystrophy. Not only they are easy to use and have a good visual effect, but they also help patients with social rehabilitation.

Contact Lens Solutions Toxicity Evaluation by the Bioluminescence Method

Purpose. To study the possibility of using bioluminescence biotesting to evaluate the toxicity of contact lens care solutions.Methods. The examined solutions were tested both immediately upon unpacking (i.e. sterile) and after rinsing “Pure Vision 2” lenses in them (i.e. after use). As a test system, NADH:FMN oxidoreductase and luciferase bacterial bio enzyme system was used. It contained lyophilized highly purified ferments of EC 1.14.14.3 bacterial luciferase (0.4 mg/ml) from E.coli recombinant variant and EC 1.5.1.29 NADH:FMN oxidoreductase (Ph. leiognathi) (0.18 enzyme units). The bioluminescent testing was carried out with TriStar LB 941 microplate luminometer (Germany). The measurement of the luminescence intensity was carried out in two repetitions. Residual luminescence (T, %), calculated as the ratio of the average maximum luminescence intensities of the experimental measurement (solution) and the control measurement, multiplied by 100%, was used as an integral indicator. Results. The results of bioluminescent testing of sterile solutions showed that “Maxima” solution exhibited the greatest inhibition of bioluminescence, while “Optimed” (Russia) and “AVIZOR Aqua Soft Comfort” solutions demonstrated the least effect. “Bausch + Lomb Biotrue” solution did not affect the bioluminescence. The results of bioluminescence testing of the solutions after contact lenses that had previously been worn for 10 hours were stored in them, showed a strong inhibition of bioluminescence in all solutions. Conclusion. The results of the toxicity evaluation allow for a more reliable prognosis of the long-term consequences of using certain solutions by contact lens wearers from risk groups. The findings also provide more insight into the mechanisms of development of discomfort and other reasons for refusing to wear lenses, as well as to suggest more effective prevention measures.

Pathogenesis of Increased Intraocular Pressure in Primary Open‑Angle Glaucoma: Literature Review

Introduction. Despite the high socio-economic significance of primary open-angle glaucoma (POAG), the etiotropic and pathogenetic treatment of this disorder has not yet been implemented, since the mechanisms of the development of this disease are not fully known and understood. One of the topical issues is the pathogenesis of ophthalmic hypertension in POAG.Purpose. To summarize the currently known mechanisms of ophthalmic hypertension in POAG to search for potential molecular targets for pathogenetic pharmacotherapy.Materials and methods. Analysis of publications on PubMed, Medline and eLibrary.Results. Ophthalmic hypertension in POAG emerges due to increased resistance to aqueous humor (AH) outflow. It is caused by increased stiffness of Schlemm’s canal endothelium and trabecular meshwork as a result of changes in the structure and biomechanical properties of its cells and extracellular matrix. These changes are determined by the interaction of signaling molecules in the form of a pathological circle, the main links of which are TGF-β2 and its receptor, Smad 2/3/4, YAP/TAZ, sFRP-1 and CTGF.Conclusion. The cause of ophthalmic hypertension in POAG is fibrosis of the trabecular meshwork. This pathological process is based on the interaction of proteins, the main of which are TGF-β2 and its receptor, Smad 2/3/4, YAP/TAZ, sFRP-1 and CTGF. These molecules can become promising targets for the pathogenetic pharmacological therapy of POAG.

Analysis of Ocular Biometric Parameters in Patients with Cystoid Macular Edema

Relevance. Cataract surgeries are among the most frequently performed ophthalmic surgeries in the world. Despite the fact that they become less traumatic every year, such interventions are still accompanied by post-surgery complications, one of which is cystic macular edema (CME) or Irwin–Gass syndrome. Purpose. To analyze ocular biometric parameters in patients with CME. Material and Methods. The study included 40 patients (40 eyes) with post-surgery CME. All patients underwent ultrasound biometry, axial length measurement, crystalline lens thickness measurement with Bio&Pachy Meter AL-4000 (Tomey, Japan) and optical coherence tomography (OCT) with Cirrus HD-OCT 5000 (Carl Zeiss, Germany) to assess central foveal thickness. Depending on the axial length, all eyes were divided into “long” and “short” relative to the average axial length of 23.3 mm. The data was analyzed with STATISTICA 10 software (StatSoft Inc., USA). Results. The incidence of CME after uncomplicated cataract surgery in Cheboksary branch of the S. Fyodorov Eye Microsurgery Federal State Institution amounted to 0.002%. Axial length among patients with CME ranged from 20.53 mm to 25.4 mm; the average value amounted to 22.67 ± 1.05 mm. The majority of eyes were “short” – 31 eyes (77.5%), whereas 9 eyes (22.5%) were “long”. “Short” eyes exhibited a greater crystalline lens thickness (4.81 ± 0.53 mm) compared to “long” eyes (4.42 ± 0.42 mm) (рM-U = 0.014). Conclusion. The development of CME after uncomplicated cataract surgery is more often observed in eyes with axial length smaller than 23.3 mm.

Differentiated Approach to Strategies of Surgical Treatment of Idiopathic Macular Holes

Background. 25G or 27G three-port vitrectomy, followed by staining and removal of the internal limiting membrane with vitreous cavity air or gas tamponade, is one of the main modern vitreoretinal surgery principles for primary macular holes. However, not all patients manage to obtain a functional outcome when the anatomical outcome is achieved. Purpose. To present clinical cases of surgical treatment of idiopathic macular holes (IMH) exhibiting a differentiated approach.Matherials and methods. This article analyzes clinical cases of four patients with primary idiopathic macular holes, differing in terms of development, hole diameter and the presence of comorbidities. Results. The results of surgical treatment were evaluated 14 days and 1 month after surgery. In all clinical cases, surgical treatment resulted in a positive anatomical outcome by blocking a retinal defect. Best corrected visual acuity increased, on average, from 0.08 ± 0.05 to 0.4 ± 0.05.Conclusion. The analysis of the presented clinical cases clearly demonstrates the need for a timely and differentiated approach to the treatment of patients with IMH, that considers etiology of the pathological process, period of its existence as well as concomitant and general somatic pathologies.

The Hard Facts on GP Contact Lens Care

The article is designed to explain the various steps needed to be undertaken daily to keep gas permeable (GP) contact lenses clean, wettable, and free from pathogens that could cause ocular disease. It explains why the steps need to be performed and what the adverse consequences of failing to perform them might be.Translation of the article: Ruslan Tahaveev (Academy of Medical Optics and Optometry

Cosmetics and Contact Lenses: Influence on Safety

The article describes the effect of decorative cosmetics on the material of soft contact lenses and studies specific features that can be observed in SCL wearers who use cosmetics extensively. Examples of complications associated with the use of various cosmetic products that may occur in contact lens wearers are given. Conclusion: in cases when patients have complaints about discomfort and dry eyes, doctors should pay attention to the amount of decorative cosmetics used as well as study the effect it can have on the surface of the contact lenses.

Some Aspects of Prescribing Treatment for Children with Myopia and Excessive Tension of Accomodation in the Practice of the Ophthalmologist of the Outpatient Clinic

Purpose. To study the preferences of ophthalmologists in the implementation of therapeutic and diagnostic measures in children with myopia and habitually excessive tension of accommodation (HETA) as part of a routine clinical practice. Material and methods. The study was conducted based on outpatient ophthalmologists’ offices. The analysis involved 64 medical questionnaires received from 32 doctors from 23 cities of Russia (2 questionnaires of the same type were filled in, each for 20 patients) and information about 1280 clinical cases of myopia or habitually excessive tension of accommodation, documented in the medical records of children aged 5 to 17 years, diagnosed with myopia (863 children, 67.4% of the surveyed) or habitually excessive tension of accommodation (417 children, 32.6%). Data was sourced from medical treatment records and a survey of doctors’ opinions. Results. In the structure of juvenile myopia, the most commonly observed degrees are mild (49.36%) and moderate (37.31%). The recentness of myopia is proportional to its degree. Most often, for treating juvenile myopia and HETA, doctors combine a drug therapy aimed at improving accommodation (96.5%) with functional methods of treatment. Phenylephrine hydrochloride preparations such as Irifrin® and Irifrin® BK (28.44 and 33.13%, respectively), as well as the combined preparation Midrimax® (36.41%) were most often used as drug therapy. To improve accommodation, ophthalmologists of outpatient clinics more often prescribe a one-month course of drug instillations, and 50% of the respondents undergo it twice a year. However, the number of patients who rated the degree of satisfaction and adherence to therapy as high and very high turned out to be higher in cases when such courses were underwent 4 times a year, compared with the group of patients who underwent them 2 times a year. Conclusion. Convenience of use of Irifrin®, Irifrin® BK and Midrimax® drugs, combined with their availability, make it possible to recommend them for a wide clinical use – treatment of patients with myopia and habitually excessive tension of accommodation.

Symptomatic Metabolic Treatment of Ophthalmopathies in Patients with COVID-19-Associated Pneumonia

Background. The causative agent of the coronavirus infection – SARS-CoV-2 – remains active and causes new cases despite the measures taken around the world. In order to timely detect ophthalmopathies in patients with dyslipidemia who have gone through COVID-19-associated pneumonia, prospective observation during the period of convalescence is advisable, justified and relevant. The assessment of the microcirculation of the bulbar conjunctiva is simple, non-invasive, safe, and allows assessing changes in the entire microcirculatory system of the body. Purpose. To study the features of the somatic status, hemodynamics of the bulbar conjunctiva in patients with dyslipidemia who have gone through COVID[1]19-associated pneumonia, depending on gender, homocysteine and cystatin C indicators during symptomatic therapy. Methods. 55 patients (110 eyes) with a documented diagnosis of COVID-19-associated pneumonia with an increased level of homocysteine and cystatin C were prospectively examined 3 months after discharge from the hospital. After consulting with therapist, cardiologist and functional diagnostics doctor, patients were divided into two groups according to gender. Results. In both groups, the dependence of the severity of lung damage on age was noted: Spearman’s correlation coefficient (r) amounted to r = 0.4; p = 0.017 and r = 0.5; p = 0.045, respectively. A direct correlation on the stage of AH was noted in patients of Group 1 (r = 0.4; p = 0.016), however, in patients of Group 2, this dependence was not found to be significant (r = 0.2; p = 0.367). There were no statistically significant changes in lipid profile in patients of both groups. The severity of endotheliosis during the period of convalescence in the study groups was confirmed by the average values of homocysteine and cystatin C compared to the reference values (1.4/1.6 and 1.62/1.67 times higher, respectively). A month of symptomatic metabolic treatment (Rosuvastatin, 1 mg of folic acid three times a day, 1 pill of Combilipen once a day, 1 drop of Chiloparin[1]Komod solution in both eyes 3 times a day) has shown its effectiveness in the course of changes in bulbar conjunctival microcirculation and disturbed total tear secretion in patients of both groups. Conclusion. In patients who went through COVID-19-associated pneumonia, markers of endotheliosis (homocysteine and cystatin C) remain during the period of convalescence, which indicates the severity of endotheliosis and the need for symptomatic metabolic treatment.