SARS-COV-2 PANDEMIC FROM THE OPHTHALMOLOGIST`S PERSPECTIVE. A REVIEW.

In December 2019, a novel coronavirus (CoV) epidemic, caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) emerged from China. Coronaviruses belong to enveloped ssRNA viruses and are classified into four genera: Alpha coronavirus, Beta coronavirus, Gamma coronavirus and Delta coronavirus. It is assumed that SARS-CoV-2 is spread primarily during a personal contact via bigger respiratory droplets. These droplets with viruses can be directly inhaled by other people or can lend on the surfaces with the possibility of further spreading. The ocular surface has been suggested as one of possible infection entries. Human eye has its own renin-angiotensin system with present ACE2 receptors, which bind the virus through spike protein. The most common symptoms of the SARS-CoV-2 infection are fever, cough and dyspnoea. Several clinical entities, such as conjunctivitis, anterior uveitis, retinitis, and optic neuritis have been associated with this infection. The most common ophthalmologic symptom associated with COVID-19 disease is conjunctivitis. Some studies indicate that eye symptoms are commonly present in patients with severe COVID-19 pneumonia and that it is possible to detect viral RNA from the conjunctival sac of these patients. In ophthalmologic praxis, we manage not only the therapy of the eye structures` inflammation in relation with this infection, but also the overall management of the visits and the supervision of the patients who are at risk and positive for coronavirus. Ophthalmologists could potentially have a higher risk of SARS-CoV-2 infection due to personal communication with the patients, frequent exposure to tears and eye secrets and the use of devices. We would like to provide an ophthalmologist`s perspective on this topic.

PUPILLOTONIA AND ADIE SYNDROME.

The aim of the work is to approach the examination of the pupil with a focus on anisocoria, its characteristics and approach to the diagnosis of pupillotonia and Adie's syndrome and its clinical evaluation. Pupil function is important not only in neurophthalmological examination but also in general ophthalmological examination. First of all, we need to know how the reflex arc works in order to be able to exclude or confirm whether the parasympathetic or sympathetic is affected. It is also necessary to know the exact characteristics of the pupil, such as size, shape, placement, function and reaction to light and at close range. Only on this basis can we distinguish pathological features. We do not often encounter this diagnosis, but it is necessary to keep it in mind, especially in the field of neurophthalmology but also in general ophthalmology. We also present three cases of pupilotonia and Adie's syndrome, which we diagnosed at the Department of Ophthalmology, Faculty of Medicine, Comenius University, after the patient himself came by emergency admission or was sent directly to ophthalmology clinic. In the discussion, we present various other diagnoses, where the reflex arc may not be affected, but the pathological pupil is caused by intraocular tumors, general systemic diseases and, last but not least, local therapy or alkaloids.

EFFECT OF MULTIPLE VARIABLES ON THE REFRACTIVE ERROR AFTER CATARACT SURGERY.

PURPOSE: To analyze refractive results after cataract surgery in relation to used type of monofocal intraocular lens, calculation formula, to age, gender and laterality. SETTINGS: Department of Ophthalmology, Comenius University and University hospital in Bratislava, Slovakia Methods: We analyzed 173 eyes (118 patients) after uneventful cataract surgery. We calculated prediction error (PE) and mean absolute error (MAE) of postoperative refraction. RESULTS AND CONCLUSION: We found no statistically significant differences in PE and MAE in relation to types of used IOL, calculation formulas, gender, age or laterality. Key words: Optical biometry, monofocal IOL, IOL calculation, refractive error.

The optic nerve drusen and haemodynamics.

PURPOSE: The optic nerve drusen (DON) are precisely described in many papers. But fewer papers evaluate real haemodynamics parameters (HP) in DON. Clinically, it has been shown, that the development and progression of visual field changes in DON is closely related to the hemodynamics of the ocular vascular supply - the optic nerve. DON can visually overlap the excavation optic disc, making it difficult to evaluate scotomas of the visual field in glaucoma. METHODS: HP was prospectively evaluated in 54 patients with compensated intraocular pressure and DON. The drusen at the optic nerve head have been detected by fundus examination and B-scan ultrasonography (USG). DON were divided into 3 groups according to the size of the individual drusen or the drusen complex. I. Group: area size up to 1.9 mm. II. Group: area size: 1.9 - 3.9 mm. III. Group: area size: 4,0 mm. HP - maximum systolic velocity (MSV), minimal diastolic velocity (MDV) and resistance indices (IR) and index pulsatility (IP) - were recorded at the central retinal artery (CRA), at the central retinal vein (CRV), at ciliares posteriores arteries breves (CPAb) and at the ophthalmic artery (AO). The values were divided into 3 groups: 1 - Physiological: CRA: 8.7 ± 0.9 / 2.9 ± 0.6 cm/s or RI: 0.70 ± 0.05. 2 - Slightly impaired: CRA: 6.6 ± 0.8 / 2.0 ± 0.5 cm/s, or RI: 0.75 ± -0.04. 3 - Significantly impaired: CRA: 5.2 ± 1.2 / 1.9 ± 0.7 cm/sec or RI: 0.79 ± 0.03. RESULTS: There was no linear relationship between size of DON and HP. Slight worsening of HP at the CRA was in I. Group (28.6 %), II. Group (48.3 %) and III. Group (62.4 %). Significant worsening of HP at the CRA was I. group (28.6 %), II. Group (48.3 %) and in III. Group (62.4 %). HP of the CPA and of the OA were not significant due to the presence and size of drusen. The relationship between individual variables was evaluated using the Pearson correlation coefficient 0.213. I. Group P: 0.354, II. Group P: 0.073, III. Group P: 0.287. CONCLUSIONS: HP is more often impaired in „large“ DON (Group III), rarely in Group I, but this is not a rule. HP cannot be predicted according to the size of the druse formation at the optic nerve. It seems that the deterioration of HP depends not only on the DON size but also on the location (the distance from the lamella cribriformis) and also to the vascular system intrapapillary.

INTRAVITREAL THERAPY OF ENDOGENOUS ENDOPHTALMITIS DUE TO UROSEPSIS - A CASE REPORT.

A case report of 58-year-old man with endogenous endophtalmitis due to urosepsis and bronchitis. Patient was hospitalized in Department of Internal Medicine another hospital. He was sent to consiliar examination to our Ophtalmology Department with worsening vision and pain in left eye one day after onset. The diagnose endogenous endophtalmitis was set. Visual aquity was a hand movement on the first visit. Intravitreal therapy was realized promptly that day, a combination of two antibiotic drugs (ceftazidim 2mg/ 0.1 ml a vankomycin 1 mg/ 0.1 ml) and antifungal agent (amfotericin B 10 μg/ 0.1 ml). This therapy was applicated 3x totally, in two weeks. Humour from anterior chamber was taken during first intravitreal application and was negative. Blood culture was positive for staphylococcus aureus. Intravenous treatment with antibiotics (gentamycin 240 mg i.v. á 24hours a amoxicilin with clavulan acid 1.2 g i.v. á 8 hod) was set for two weeks then continued antibiotic (ciprofloxacin 500 mg á 12 hours) and antifungal therapy (itrakonazol 100 mg á 12 hod) per os two months. Visual aquity of the left eye was 20/100 after four weeks and 20/40 after two months. We would like to highlight advantage of multidisciplinary co-operation.

Combination of Intravitreal Corticosteroid with Anti-vegf in Macular Edema Secondary to Retinal Vein Occlusion.

PURPOSE: functional and anatomical results after combination of intravitreal dexamethasone implant with anti-VEGF bevacizumab in macular edema secondary to retinal vein occlusion. METHODS: Retrospective analysis of 50 patients, average age 72 years, 15 men and 35 women. Inclusion criteria for treatment were retinal vein occlusion, best corrected visual acuity (BCVA) more than 20/200 and macular edema more than 250 µm. Algorithm of treatment was dexamethason, anti-VEGF (bevacizumab), dexamethason. Application of anti-VEGF bevacizumab was in interval between two applications of dexamethasone, for the first time in every patient. If there were nonperfusion areas on fluoresceine angiography (FA), or ischemia on slit lamp, repeatedly. Patients observed for 12 months at least. This cohort included patients with branch retinal vein occlusion together with central retinal vein occlusion. This is an evaluation of nonperfusion areas based on FA, BCVA, macular edema on optical coherence tomography (OCT) and number of reapplication of anti-VEGF bevacizumab. Observed adverse effects are elevation of intraocular pressure and number of patients who underwent cataract surgery. RESULTS: The gain of 8 letters in 1st month after 1st application of dexamethasone, central retinal thickness (CRT) reduced from 512 µm to 318 µm in average. 33 patients get 1, 3 patients get 2 and 14 patients 3 injections of bevacizumab. On the day of 2nd application of dexamethasone, in 7th month in average, the CRT increased on 465 µm, and 1th month after, the gain from the baseline was 10 letters and CRT reduced on 380 µm. All the patients were phackic at the baseline, 18 (36 %) patients underwent cataract surgery with intraocular lens implantation. Transient elevation of intraocular pressure in 15 (30 %) eyes, treated by local therapy. CONCLUSION: Combination of intravitreal dexamethasone implant with anti-VEGF bevacizumab is functionally and anatomically effective. Key words: retinal vein occlusion, macular edema, dexamethasone, bevacizumab.

Prevalence of refractive errors in the Slovak population calculated using the Gullstrand schematic eye model.

PURPOSE: A substantial part of the population suffers from some kind of refractive errors. It is envisaged that their prevalence may change with the development of society. The aim of this study is to determine the prevalence of refractive errors using calculations based on the Gullstrand schematic eye model. METHODS: We used the Gullstrand schematic eye model to calculate refraction retrospectively. Refraction was presented as the need for glasses correction at a vertex distance of 12 mm. The necessary data was obtained using the optical biometer Lenstar LS900. Data which could not be obtained due to the limitations of the device was substituted by theoretical data from the Gullstrand schematic eye model. Only analyses from the right eyes were presented. The data was interpreted using descriptive statistics, Pearson correlation and t-test. The statistical tests were conducted at a level of significance of 5%. RESULTS: Our sample included 1663 patients (665 male, 998 female) within the age range of 19 to 96 years. Average age was 70.8 ± 9.53 years. Average refraction of the eye was 2.73 ± 2.13D (males 2.49 ± 2.34, females 2.90 ± 2.76). The mean absolute error from emmetropia was 3.01 ± 1.58 (males 2.83 ± 2.95, females 3.25 ± 3.35). 89.06% of the sample was hyperopic, 6.61% was myopic and 4.33% emmetropic. We did not find any correlation between refraction and age. CONCLUSION: Females were more hyperopic than males. We did not find any statistically significant hypermetopic shift of refraction with age. According to our estimation, the calculations of refractive errors using the Gullstrand schematic eye model showed a significant hypermetropic shift of more than +2D. Our results could be used in future for comparing the prevalence of refractive errors using same methods we used.Key words: refractive errors, refraction, Gullstrand schematic eye model, population, emmetropia.

The influence of HLB on the encapsulation of oils by complex coacervation.

Microcapsules are used for the formulation of drug controlled release and drug targeting dosage forms. Encapsulated hydrophobic drugs are often applied as their solutions in plant oils. The uptake of the oils in the complex coacervate microcapsules can be improved by the addition of surfactants. In this study, soybean, olive and peanut oils were chosen as the representatives of plant oils. The well characterized complex coacervation of gelatin and acacia has been used to produce the microcapsules. The amount of encapsulated oil has been determined gravimetrically. The encapsulation of the oils was high (75-80%). When the surfactants with HLB values from 1.8 to 6.7 were used, the amount of encapsulated oil was high (65-85%). A significant decrease of the oil content in the microcapsules was found when Tween 61 with HLB = 9.6 had been added into the mixture. No oil was found inside the microcapsules from the coacervate emulsion mixture containing Tween 81 (HLB = 10) and Tween 80 (HLB = 15), respectively. The results of the experiment confirm the dependence of hydrophobic substance encapsulation on the HLB published recently for Squalan.