Optical Coherence Tomography Angiography Assessment of the Optic Nerve Head in Patients Hospitalized Due to COVID-19 Bilateral Pneumonia.

Background and objectives: We aimed to investigate changes in the radial peripapillary capillary (RPC) network using optical coherence tomography angiography (OCTA) in patients who recovered from coronavirus disease 2019 (COVID-19). Materials and Methods: This was a prospective study of patients hospitalized due to COVID-19 bilateral pneumonia between March and May 2021. The control group included healthy individuals matched for age and sex. Two months after discharge, the patients underwent ophthalmological examination, including optical coherence tomography (OCT) imaging. The RPC network and retinal nerve fiber layer (RNFL) of the optic disc (RNFL optic disc) were automatically evaluated and compared between the study groups. Additionally, the RPC parameters were compared between the men and women in the COVID-19 group, and correlations between the RPC and RNFL optic disc parameters were assessed. Results: A total of 63 patients (120 eyes) with bilateral pneumonia caused by severe acute respiratory syndrome coronavirus 2 infection were examined. No ophthalmic symptoms were reported by the patients. No significant differences were observed in the RPC parameters between the patients from the COVID-19 group and the 43 healthy controls. Moreover, the RPC parameters did not differ between the men and women in the COVID-19 group. A positive correlation was found between the RPC and RNFL optic disc parameters in the COVID-19 patients (p < 0.001). Conclusions: No changes in the RPC network were observed among the patients with COVID-19 bilateral pneumonia in the early period after hospital discharge. However, a longer follow-up is needed to monitor COVID-19-related changes in the microvasculature of the optic nerve head.

The Impact of a Single Haemodialysis Session on the Retinal Thickness and Optic Nerve Morphology.

BACKGROUND: The aim of the study was to assess the influence of a single haemodialysis (HD) session on the retinal and optic nerve morphology in end-stage kidney disease (ESKD) patients. METHODS: It is a prospective study including only the right eye of 35 chronic kidney disease (CKD) patients subjected to HD. Each patient underwent a full eye examination 30 min before HD (8 a.m.) and 15 min after HD. Optical coherence tomography (OCT) was used to assess the peripapillary retinal nerve fibre layer (pRNFL) thickness, macular nerve fibre layer (mRNFL) thickness, ganglion cell layer with inner plexiform layer thickness (GCL+), GCL++ (mRNFL and GCL+) thickness, total retinal thickness (RT) and total macular volume (TMV). The correlation was tested between such systemic parameters changes as systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), body weight, plasma osmolarity and ocular perfusion pressure (OPP) and ultrafiltration volume with total RT and pRNFL thickness changes during HD. RESULTS: In the results of a single HD session, we could observe a statistically significant increase in the total RT thickness (pre-HD 270.4 ± 19.94 µm, post-HD 272.14 ± 20.11 µm; p = 0.0014), TMV (pre-HD 7.48 ± 0.53 mm3, post-HD 7.52 ± 0.55 mm3; p = 0.0006), total pRNFL thickness (pre-HD 97.46 ± 15.71 µm, post-HD 100.23 ± 14.7 µm; p = 0.0039), total GCL+ thickness (pre-HD 70.11 ± 9.24 µm, post-HD 70.6 ± 9.7 µm; p = 0.0044), and GCL++ thickness (pre-HD 97.46 ± 12.56 µm, post-HD 97.9 ± 12.94 µm; p = 0.0081). We observed a significant correlation between the change in total RT and DBP change, as well as between body weight change and the change in total pRNFL thickness. There was also a correlation between total pRNFL thickness change and the presence of diabetes mellitus. CONCLUSION: Even a single HD session affects the retinal and pRNFL thickness, which should be taken into account when interpreting the OCT results in patients subjected to HD. The impact of changes after a single HD session on selected parameters requires further assessment in subsequent studies, including long-term observation.

The Haemodialysis Session Effect on the Choroidal Thickness and Retinal and Choroidal Microcirculation-A Literature Review.

Haemodialysis (HD) is currently the most commonly used method of renal replacement therapy. The process of dialysis involves numerous changes that affect many systems, including the eye. The changes occurring in the course of HD may affect the ocular parameters, such as intraocular pressure, central corneal thickness, retinal thickness, retinal nerve fibre layer thickness, and choroidal thickness (CT). The choroid, being one of the most vascularized tissues, is characterized by the highest ratio of blood flow to tissue volume in the entire body, may be particularly susceptible to changes occurring during HD, and at the same time reflect the microcirculatory status and its response to HD. Patients with end-stage renal disease subjected to dialysis are highly susceptible to systemic microvascular dysfunction. Moreover, it is considered that the process of HD itself contributes to vascular dysfunction. Nowadays, thanks to the development of imaging techniques, the widely available optical coherence tomography (OCT) tests allow for the assessment of CT, while OCT-angiography allows for a quick, non-invasive, and repeatable assessment of the condition of retinal and choroidal microcirculation, which significantly expands our knowledge regarding the reaction of ocular microcirculation due to HD. The assessment of both retinal and choroidal circulation is even more attractive because retinal circulation is autoregulated, while choroidal circulation is mainly controlled by extrinsic autonomic innervation. Thus, assessment of the choroidal response to an HD session may provide the possibility to indirectly evaluate the functions of the autonomic system in patients subjected to HD. At a time when the importance of microcirculation in systemic and renal diseases is becoming increasingly evident, the assessment of ocular microcirculation appears to be a potential biomarker for assessing the condition of systemic microcirculation. In this work, we present a review of the literature on the effect of the HD session on CT and the retinal and choroidal microcirculation.

Long-term mortality after retinal artery occlusion - a single centre study.

INTRODUCTION AND OBJECTIVE: Retinal artery occlusion (RAO) is an ophthalmic and systemic emergency requiring urgent diagnosis and treatment. Data regarding mortality in this group, especially in the European population, are modest. The aim of this study is to assess all-cause mortality in post-RAO patients. MATERIAL AND METHODS: This is a retrospective, single-centre study involving 198 patients following RAO diagnosed in 2004-2020. The control group included 198 patients after cataract surgery matched for gender and age, with the date of cataract surgery corresponding to the date of the RAO. RESULTS: The average follow-up of the study population was 6.32±2.15 years. Post-RAO patients had significantly higher risk of all-cause mortality (Log-rank test p = 0.001), also when stratified for ages below 75 years (Log-rank test p = 0.016) and those aged 75 and over (Log-rank test p = 0.001). In the group of patients without cardiovascular events before RAO/cataract surgery, post-RAO patients were also at higher risk of all-cause mortality (Log-rank test p = 0.011), but when stratified according to age, those observations were borderline significant (Log-rank test p = 0.083 for a group of patients aged less than 75 years, and p = 0.051 for patients aged 75 and over). Cox analysis showed that in the group of post-RAO patients, the main risk factors for all-cause mortality were age (HR 1.07, 95%CI 1.04-1.1; p < 0.001), ischemic heart disease (HR 1.72; 95%CI 1.08-2.72; p = 0.022), and permanent atrial fibrillation (HR 2.18, 95%CI 1.08-4.38; p = 0.029). CONCLUSIONS: Regardless of age and previous cardiovascular events, post-RAO patients are at a higher risk of all-cause mortality than patients without a history of RAO.

Long-Term Effect of SARS-CoV-2 Infection on the Retinal and Choroidal Microvasculature.

The purpose of this study was to evaluate the persistent changes in microvascular parameters based on optical coherence tomography angiography (OCTA) in patients hospitalized due to COVID-19 bilateral pneumonia. The case-control prospective study was carried out among 49 patients with COVID-19 and 45 healthy age- and gender-matched 2 and 8 months after hospital discharge. We found a significantly decreased vessel density (VD) in superficial capillary plexus (SCP) in COVID-19 patients. Significantly decreased vessel density (VD) in the superficial capillary plexus (SCP), the deep capillary plexus (DCP), and choriocapillaris (CC), with significantly increased vessel density observed in the choriocapillaris in the foveal area (FCC). The foveal avascular zone in DCP (FAZd) was significantly increased in the COVID-19 group. We found differences between OCTA parameters according to gender. The foveal VD in SCP and DCP was significantly decreased in women compared to men. The FAZ area in SCP (FAZs) and superior VD in the choriocapillaris (SCC) were significantly increased in women. In conclusion, we noticed persistent changes in the ocular parameters of OCTA in COVID-19 patients. At the second follow-up visit, we observed a widened FAZ zone in SCP and decreased VD in some regions of the retina and choroid.

The Effect of Reduced Oxygen Saturation on Retinal Microvascularization in COVID-19 Patients with Bilateral Pneumonia Based on Optical Coherence Tomography Study.

The aim of the study was to evaluate changes in the retinal thickness and microvasculature based on optical coherence tomography (OCT) depending on baseline oxygen saturation (SpO2) in patients hospitalized due to COVID-19 bilateral pneumonia. The prospective study was carried out among 62 patients with COVID-19 pneumonia who underwent ophthalmic examination after hospital discharge. They were divided into three groups depending on the oxygen saturation (SpO2) on admission: ≤90% (group 1), >90% and ≤95% (group 2), and >95% (group 3). The following parameters were assessed in the ophthalmological examination and correlated with the baseline SpO2: ganglion cell layer (GCL), the retinal nerve fiber layer (RNFL) in the macular area, RNFL in the peripapillary area, the foveal avascular zone (FAZ) in superficial capillary plexus (SCP) and deep capillary plexus (DCP), vessel density (VD) in SCP, in DCP, and in the choriocapillaris plexus (CC). Baseline saturation ≤90% in COVID-19 patients caused a decrease of VD in some areas of SCP and DCP and an increase in FAZ area in SCP and DCP. In the group of patients with SpO2 ≤ 90% statistically significant thinning of the retina in the inner superior ring (ISR) (p = 0.029), the inner temporal ring (ITR) (p = 0.34), the outer superior ring (OSR) (p = 0.012), and the outer temporal ring (OTR) (p= 0.004)] was observed. The statistically significant thickening of RNFL optic disc and thinning of RNFL retina in some macular areas in patients with SpO2 ≤ 90% were reported. The size of FAZ area in SCP and vessel density were significantly greater in some areas of SCP, DCP, and CC in patients with SpO2 ≤ 90% (p = 0.025). Baseline oxygen saturation ≤90% has been found to influence the ocular parameters of OCT in COVID-19 patients. We noticed a widened FAZ zone in SCP and increased VD in some regions of the retina and choroid as a response to systemic hypoxia.

BNT162b2 (Pfizer/BioNTech) COVID-19 Vaccination Was Not Associated with the Progression of Activity of the Exudative Form of Age-Related Macular Degeneration during Anti-VEGF Therapy.

BACKGROUND: Evaluation of the activity of the exudative form of age-related macular degeneration (AMD) during anti-vascular endothelial growth factor (anti-VEGF) therapy before and after administration of BNT162b2 (Pfizer/BioNTech) vaccination. METHODS: The optical coherence tomography and best corrected visual acuity (BCVA) records of the two previous visits before the first dose of BNT162b2 (first pre-vaccination visit marked as "V-1", the previous pre-vaccination "V-2"), and two subsequent visits after the second dose of vaccination (first visit after the second dose marked as "V1", second visit after the second dose marked as "V2") were collected for 63 eyes of 59 patients. RESULTS: The difference in the average retinal thickness was observed between the last and each other checkpoint for the aflibercept group and in the overall outcome. The maximum thickness from the inner retinal surface to the inner border of RPE decreased during the observation; differences were observed comparing visits -2 and 1. Subretinal complex thickness decreased during follow-up, and the differences were observed between visits -2 and 2. There were no statistically significant differences in the BCVA and the occurrence of intraretinal cystoid fluid, serous PED, subretinal hyperreflective material, and retinal hemorrhage. CONCLUSION: In the present study, the activity of the exudative form of AMD did not deteriorate after the administration of the BNT162b2 vaccine.

Central Retinal Vein Occlusion After Discontinuation of Rivaroxaban Therapy in a Young Patient with COVID-19 Pulmonary Embolism: A Case Report.

BACKGROUND We present the report of the first case, to the best of our knowledge, of central retinal vein occlusion (CRVO) that occurred 3 days after anticoagulation discontinuation in a patient with a history of pulmonary embolism in the course of COVID-19. CASE REPORT A previously healthy 38-year-old man was hospitalized in April 2021 with severe COVID-19 pneumonia, complicated by segmental and subsegmental pulmonary embolism. The patient was treated with a concurrent combination of remdesivir, dexamethasone, therapeutic enoxaparin, ceftriaxone, passive oxygen therapy, and convalescent plasma therapy, which led to pulmonary improvement. The treatment with therapeutic enoxaparin (80 mg/0.8 mL twice a day) was continued for 1 month after discharge, followed by 15 mg of rivaroxaban twice a day for 3 weeks and 20 mg of rivaroxaban once a day for 11 weeks. Within 3 days after rivaroxaban discontinuation, the patient experienced a decrease in visual acuity in his right eye, to the level of 5/25. Nonischemic CRVO with cystoid macular edema was diagnosed and an intravitreal injection of ranibizumab was performed. Common identifiable factors contributing to CRVO were excluded, and the treatment with prophylactic enoxaparin was initiated. Two weeks later, macular edema decreased significantly and visual acuity improved to 20/20. The treatment with enoxaparin was discontinued. CONCLUSIONS Rebound hypercoagulability after discontinuation of rivaroxaban therapy can manifest as CRVO in a young patient with a history of COVID-19 pulmonary embolism. It was successfully treated with an intravitreal injection of ranibizumab.

Retinal Artery Occlusion and Its Impact on the Incidence of Stroke, Myocardial Infarction, and All-Cause Mortality during 12-Year Follow-Up.

The aim of the study was to evaluate the incidence of ischemic stroke, myocardial infarction, and all-cause mortality in patients with retinal artery occlusion (RAO). This single-center retrospective study included 139 patients diagnosed with RAO between 2009 and 2020. The control group included 139 age- and sex-matched patients without RAO who underwent cataract surgery. The year of the surgery corresponded to the year of RAO onset. During the 12-year follow-up, patients with RAO had a shorter time to death (49.95 vs. 15.74 months; p = 0.043), a higher all-cause mortality rate (log-rank p = 0.026, and a higher rate of the composite endpoint, including ischemic stroke, myocardial infarction, and all-cause mortality (log-rank p = 0.024), as compared with controls. Patients with RAO younger than 75 years showed a higher risk of cerebral ischemic stroke (log-rank p = 0.008), all-cause mortality (log-rank p = 0.023), and the composite endpoint (log-rank p = 0.001) than controls. However, these associations were not demonstrated for patients aged 75 years or older. Our study confirms that patients with RAO have a higher risk of all-cause mortality than those without RAO. Moreover, patients with RAO who are younger than 75 years are significantly more likely to experience ischemic stroke, death, or the composite endpoint after an occlusion event, as compared with individuals without RAO.

Retinal Microvascular Changes in COVID-19 Bilateral Pneumonia Based on Optical Coherence Tomography Angiography.

The purpose of this study was to evaluate retinal and choroidal microvascular alterations with optical coherence tomography angiography (OCTA) in COVID-19 patients hospitalized because of bilateral pneumonia caused by SARS-CoV-2. The vessel density (VD) and foveal avascular zone (FAZ) of 63 patients with SARS-CoV-2 pneumonia who had positive polymerase chain reaction (PCR) tests and who recovered after receiving treatment and 45 healthy age- and gender-matched controls were evaluated and compared using OCTA in the superficial capillary plexus (SCP) and deep capillary plexus (DCP). The VD was also estimated in both groups in the choriocapillaris (CC). In COVID-19 patients, there was a statistically significant difference between the patients and a control group in both superficial (FAZs) and deep (FAZd) avascular zone (p = 0.000). The VD was significantly lower in the foveal area in choriocapillaris (p = 0.046). There were no statistically significant changes in the VD in the superior, inferior, nasal, and temporal quadrants in superficial and deep plexus, or in the choriocapillaris. The VD was not significantly lower in the foveal area in superficial or deep plexus. COVID-19 may affect the retinal vasculature, causing ischemia, enlargement of the FAZ, and lowering of the VD in the choriocapillaris area. Routine ophthalmic examination after SARS-CoV-2 infection should be considered in the course of post-infectious rehabilitation.

Susac's syndrome - the crucial role of imaging tests for proper diagnosis.

INTRODUCTION: Susac's syndrome (SS) is a rare, autoimmune-mediated endoteliopathy characterized by a clinical triad of encephalopathy, branch retinal artery occlusion, and sensorineural hearing loss. SS is also characterized by a neuroimaging triad consisting of white matter lesions, grey matter lesions, and leptomeningeal enhancement on magnetic resonance imaging (MRI). Considering the rarity of SS, as well as certain similarity to other, more frequent neurological diseases, such as multiple sclerosis (MS), this syndrome is sometimes incorrectly diagnosed and treated. OBJECTIVE: The aim of the study is to present the current state of knowledge on SS, with particular consideration for the differential diagnostics between SS and MS, using the latest available imaging techniques, such as brain MRI, optical coherence tomography (OCT), OCT angiography (OCTA) and fluorescein angiography (FA). REVIEW METHODS: The major electronic databases (PubMed, Google Scholar) were searched manually in order to identify the relevant studies published on SS. BRIEF DESCRIPTION OF THE STATE OF KNOWLEDGE: Distinguishing SS from MS is a diagnostic challenge. In the majority of cases, patients with SS do not present the complete clinical or neuroimaging triad, and a delay in making the correct diagnosis exposes the patient to the occurrence of complications, resulting from the development of the underlying disease, or/and the application of improper treatment. In the case of SS the results of brain MRI and FA are essential for making the correct diagnosis as they may reveal pathognomonic changes. SUMMARY: Imaging examinations, such as brain MRI, FA, and OCT complement each other, due to which the diagnosis of SS may be simpler, irrespective of the stage of the disease.

Manifestation of Susac syndrome during interferon beta-1a and glatiramer acetate treatment for misdiagnosed multiple sclerosis: a case report.

BACKGROUND: Susac syndrome (SS) is characterized by the triad of encephalopathy, branch retinal artery occlusion, and sensorineural hearing loss. However, the diagnosis of SS remains difficult because the clinical triad rarely occurs at disease onset, and symptom severity varies. SS symptoms often suggest other diseases, in particular multiple sclerosis (MS), which is more common. Misdiagnosing SS as MS may cause serious complications because MS drugs, such as interferon beta-1a, can worsen the course of SS. This case report confirms previous reports that the use of interferon beta-1a in the course of misdiagnosed MS may lead to exacerbation of SS. Moreover, our case report shows that glatiramer acetate may also exacerbate the course of SS. To the best of our knowledge, this is the first reported case of exacerbation of SS by glatiramer acetate. CASE PRESENTATION: We present a case report of a patient with a primary diagnosis of MS who developed symptoms of SS during interferon beta-1a treatment for MS; these symptoms were resolved after the discontinuation of the treatment. Upon initiation of glatiramer acetate treatment, the patient developed the full clinical triad of SS. The diagnosis of MS was excluded, and glatiramer acetate therapy was discontinued. The patient's neurological state improved only after the use of a combination of corticosteroids, intravenous immunoglobulins, and azathioprine. CONCLUSIONS: The coincidence of SS signs and symptoms with treatment for MS, first with interferon beta-1a and then with glatiramer acetate, suggests that these drugs may influence the course of SS. This case report indicates that treatment with glatiramer acetate may modulate or even exacerbate the course of SS.

Central and Branch Retinal Artery Occlusion-Do They Harbor the Same Risk of Further Ischemic Events?

PURPOSE: Retinal artery occlusion (RAO) is associated with an increased risk of cardiovascular events such as ischemic stroke and myocardial infarction, but whether different RAO subtypes such as central retinal artery occlusion (CRAO) or branch retinal artery occlusion (BRAO) carry similar risk of these events is unclear. Our aim was to determine whether the risk of cardiovascular events differs between CRAO and BRAO. METHODS: This single-center, retrospective study included 131 patients hospitalized in our clinic in 2010-2020 with CRAO or BRAO confirmed by ophthalmic examination. Data on demographics, previous ischemic stroke and myocardial infarction, comorbidities, the results of echocardiographic and ultrasound carotid artery examinations and laboratory tests were assessed. Data on ischemic stroke, myocardial infarction, and all-cause mortality occurring after RAO were obtained from the Polish National Health Service, which collects data on all publicly funded hospitalizations. Using these data, Kaplan-Meier analyses and Cox proportional hazard regression were performed. RESULTS: Ischemic stroke occurred in 9.9% of patients after RAO: 10.6% in the CRAO group and 8.1% in the BRAO group (p = 0.662). Myocardial infarction occurred in 2.3% of patients after RAO: 2.1% in the CRAO group and 2.7% in the BRAO group (p = 0.843). All-cause mortality occurred in 22.9% of patients after RAO: 25.5% in the CRAO group and 16.2% in the BRAO group (p = 0.253). The composite endpoint of ischemic stroke, myocardial infarction, and all-cause mortality after RAO occurred in 28.2% of patients: 30.9% in the CRAO group and 21.6% in the BRAO group (p = 0.338). There was no difference between CRAO and BRAO in median time to ischemic stroke (32 vs. 76.4 months; p = 0.352), all-cause mortality (35.9 vs. 36.3 months; p = 0.876) or composite endpoint (37.5 vs. 41.5 months; p = 0.912) after RAO. The Kaplan-Meier analysis showed no differences between CRAO and BRAO in ischemic stroke, myocardial infarction, all-cause mortality, or the composite endpoint; similar results were obtained in analyses of patients with and without cardiovascular events before RAO. CONCLUSIONS: The prognosis for ischemic stroke, myocardial infarction, and all-cause mortality is similar in patients with CRAO and BRAO. Ischemic strokes occur with a similar frequency before and after RAO. Myocardial infarctions are observed significantly more frequently before an episode of RAO than after. The results of our study indicate that both CRAO and BRAO require expanded diagnostics to assess the risk of recurrent cardiovascular events, especially ischemic strokes, to implement appropriate prophylaxis and reduce mortality.

Comparison of 532 nm Micropulse Green Laser versus Continuous-Wave 532 nm Green Laser in Chronic Central Serous Chorioretinopathy: Long-Term Follow-Up.

The aim of this study was to analyze the efficacy of micropulse laser treatment (MLT) compared with the continuous-wave laser (CL) in treating eyes with chronic central serous chorioretinopathy (CSC) in a 12-month follow-up study. Methods: A retrospective observational study included 51 eyes with chronic CSC; 35 eyes were treated with MLT (Group A), and 16 eyes were treated with CL (Group B). We analyzed the best corrected visual acuity (BCVA) and retinal microstructural changes in spectral optical coherence tomography before the treatment, one and twelve months after the laser procedure. Results: The final mean BCVA was 0.89 ± 0.13 in Group A and 0.71 ± 0.17 in Group B. Photoreceptor length decreased significantly in both groups and amounted 61.2 µm in Group A and 42.9 µm in Group B one year after the treatment. Complete absorption of subretinal fluid twelve months after the laser procedure was noted in 74.3% eyes in Group A and in 87.5% eyes in group B. Hyper-reflective subretinal deposits were observed in 10/35 eyes in Group A but in 15/16 eyes in Group B on the final follow-up visit. Conclusion. MLT-treated patients showed better functional and microstructural results than patients treated with CL.

Choroidal Thickness in Women with Uncomplicated Pregnancy: Literature Review.

Pregnancy is a time when many changes occur in a woman's body. The goal of these changes is the provision of optimum conditions for the development of the foetus. Pregnancy also affects eye physiology. Well recognized physiological changes include a reduced corneal sensitivity, an increase in its central thickness and curvature, and a decrease in intraocular pressure. The association between choroidal thickness and pregnancy is not clear. Haemodynamic and hormonal changes taking place during pregnancy and the question of whether these changes are reflected by choroidal thickness are especially important. It is assumed that the choroid, which is one of the most highly vascularized tissues characterized by the highest blood flow to tissue volume ratio in the whole body, should respond by an increase in its thickness to an increase in blood flow and drop in the value of peripheral resistance. Measurement of choroidal thickness using enhanced depth imaging optical coherence tomography (EDI-OCT) in women with uncomplicated pregnancy provides important information concerning the effects of physiological changes in the eye.

Optical coherence tomography angiography vessel density in children with type 1 diabetes.

PURPOSE: To assess the optical coherence tomography angiography (OCTA) retinal vessel density and foveal avascular zone (FAZ) in children with type 1 diabetes (T1D) and compare potential pathologic early changes in this population to healthy age-matched controls. METHODS: This study included 130 pubescent children: 94 with T1D (188 eyes) and 36 of their age-matched control group (60 eyes). OCTA was performed using AngioVue (Avanti, Optivue). FAZ area (mm2) in superficial plexus, whole superficial capillary vessel density (wsVD), fovea superficial vessel density (fsVD), parafovea superficial vessel density (psVD), whole deep vessel density (wdVD), fovea deep vessel density (fdVD), parafovea deep vessel density (pdVD), foveal thickness (FT) (µm) and parafoveal thickness (PFT) (µm) were taken into analysis. Among the studied patients with T1D there were assessed codependences regarding the investigated foveal and parafoveal parameters and selected potential predictors, i.e. patient's age (years), diabetes duration time (years), age of onset of the disease (years), mean level of glycated hemoglobin (HbA1C) (%), and concentration of serum creatinine (mg/dL). RESULTS: None of the abovementioned OCT and OCTA parameters was statistically significantly different between the groups. The patient's age statistically significantly did not influent any of the OCT and OCTA parameters. Yet an elevated level of HbA1C tended to reduce the parafovea superficial vessel density (p = 0.039), and parafoveal thickness (p = 0.003) and an increased serum creatinine level correlated with the decreased whole deep vessel density (p < 0.001). The parafovea deep vessel density in the diabetic patients decreased when the serum creatinine level (p = 0.008), age of onset of the disease (p = 0.028), and diabetes duration time (p = 0.014) rose. CONCLUSIONS: Vessel density, both in superficial and deep plexuses, and FAZ area are normal in pubescent children with T1D comparing to healthy subjects. An elevated level of HbA1C correlated with reduced psVD and PFT. Longitudinal observation of these young patients is needed to determine if any of these OCTA measurements are predictive of future DR severity.

Potential of redox therapies in neurodegenerative disorders.

Recently significant advances have been made to understand the pathophysiological mechanisms of neurodegenerative disorders to provide real therapeutic benefits. There is evidence that persistent inflammation and oxidative stress are the crucial factors of ongoing cell damage in neurodegenerative complex etiology. The variety of reactive oxygen and nitrogen species are the cause of both axonal and neuronal destruction, which is pathological hallmark of neurodegeneration. Therefore, the reduction of oxidative stress is currently one of the main neuroprotective strategies. The World Health Organization (WHO) estimates that, by 2040, neurodegenerative diseases will be the main cause of death in industrialized countries ahead of the cancers. The redox therapeutic approch can target: degnerative component, inflammatory/autoimmune component and neurodegenerative component. Redox therapy should not be applied uniformly, and must be develop to target specific mechanisms. This review focus on the main antitoxidative therapies that are used in many countries as a supplements or even as a standart treatment. Aditionally, clinical synmptoms of most common neurodegenerative disordes and centralnervous system structures involved in oxidative/nitrosative stress are showed.

CHOROIDAL THICKNESS CHANGES AFTER VITRECTOMY WITH SILICONE OIL TAMPONADE FOR PROLIFERATIVE VITREORETINOPATHY RETINAL DETACHMENT.

PURPOSE: To access the potential effect of vitrectomy and silicone oil tamponade on the choroid. METHODS: Eighteen patients (18 eyes) who had undergone pars plana vitrectomy with 1,000-cSt silicone oil tamponade for proliferative vitreoretinopathy retinal detachment were included in this retrospective study. All patients underwent ophthalmologic examinations before treatment and 1 week and 1, 3, and 6 months after vitrectomy with silicone oil tamponade. Choroidal thickness was measured using enhanced depth imaging optical coherence tomography (Spectralis; Heidelberg Engineering) in a horizontal and vertical section beneath the fovea. RESULTS: Choroidal thickness statistically significantly decreased till 3 months after pars plana vitrectomy with silicone oil tamponade: under the center of the fovea (P = 0.014) and in the temporal (P = 0.029), superior (P = 0.046), and inferior areas, determined at 1,500 µm from the center of the fovea (P = 0.030). After 6 months, the desired effect in the form of a decrease in the choroidal thickness was even more prominent, both under the center of the fovea (P < 0.001) and in the nasal (P < 0.001), temporal (P < 0.001), superior (P < 0.001), and inferior areas at 1,500 µm from the center of the fovea (P < 0.001). CONCLUSION: Choroidal thickness is reduced in eyes receiving silicone oil intraocular tamponade. Silicone oil tamponade may have an impact on the structure and proper functioning of the choroid. The measurements of the choroidal thickness by optical coherence tomography might be a very good tool to detect early changes in choroidal thickness and impact the decision when to remove silicone oil.