Assessment of the optic nerve, macular, and retinal vascular effects of COVID-19.

OBJECTIVE: To evaluate the effects of SARS-CoV-2 infection on the optic nerve, macula, and retinal vascular structures. METHODS: This study included 129 participants recovering from COVID-19 and 130 healthy control subjects aged 18 to 55 years. The study was designed as observational and cross-sectional and was conducted between June 2020 and February 2021. The average thicknesses of the retinal nerve fibre layer (RNFL), ganglion cell complex (GCC), and macula also were measured using a spectral domain optical coherence tomography analysis. The vessel densities of the superficial and deep capillary plexuses of the macula, foveal avascular zone, and radial peripapillary capillary plexus of the optic disc were quantified by optical coherence tomography angiography. RESULTS: In all quadrants, the RNFL and GCC were thinner in patients with neurologic symptoms of COVID-19 (p < 0.05). None of the measurements of the Early Treatment Diabetic Retinopathy Study regions significantly differed between patients with and without COVID-19 symptoms (p > 0.05). The foveal avascular zone area, perimeter, circularity index, and vessel densities (%) of the global and inner and outer circles of superficial capillary plexuses and deep capillary plexus and global and superior and inferior halves of the radial peripapillary capillary plexus measurements were found to significantly differ between the symptomatic COVID-19 group and the asymptomatic COVID-19 and control groups (p < 0.05). CONCLUSION: RNFL and GCC thickness evaluation with optical coherence tomography and vessel density evaluation with optical coherence tomography angiography can be considered remarkable diagnostic methods for retinal neurovascular abnormalities and a biomarker for microvascular abnormalities after infection with SARS-CoV-2.

Changes in optical coherence tomography angiography in patients with vitamin D deficiency.

PURPOSE: 25-hydroxyvitamin D [25(OH)D] sufficiency has critical biological importance for the human body. Although there are several studies on the association between serum 25(OH)D levels and macular structure, the data in this regard are limited. This study mainly aimed to investigate macular microvascular structure using optical coherence tomography angiography (OCTA) in 25(OH)D deficiency. STUDY DESIGN: Prospective, single-center, clinical study. METHODS: The study included 82 eyes of 82 patients with 25(OH)D deficiency (Group I) and 50 eyes of 50 healthy subjects (Group II). All participants underwent OCTA examinations. The foveal avascular zone (FAZ) and superficial capillary plexus (SCP) and deep capillary plexus (DCP) vessel density (VD) measurements of the participants were statistically compared between the patients and healthy subjects. RESULTS: The mean 25(OH)D levels measured from the venous blood samples of the participants were 7.61 ± 3.27 ng/mL in Group I and 25.39 ± 4.16 ng/mL in Group II, and the difference between these values was statistically significant (p < 0.0001). The FAZ measurement was significantly higher in Group I. The VDs of the SCP and DCP measurements were significantly higher in Group II. When the central macular thickness values of the participants were compared, Group II had a significantly higher value, but there was no significant difference in the central macular volume and retinal nerve fiber layer thickness analyses. CONCLUSION: The results showed that the FAZ area was significantly higher and the VDs of SCP and DCP were significantly lower in the patients with 25(OH)D deficiency. We found that 25(OH)D deficiency affected macular microvascular architecture.

An investigation on well-to-wheel emissions of passenger cars in Turkey.

Passenger cars are responsible for a great amount of energy consumption and emissions in the world. Turkey is one of the world's twenty largest emission producers. The reason behind this study is to determine the most appropriate energy source for passenger cars particularly in Turkey in terms of main vehicle emissions. The results will be supportive for general inferences also. The impact of technological year, vehicle type, fuel type, fuel production, and electricity generation from different energy sources on well-to-wheel emissions for Turkey has been analyzed using the GREET software in this study. In the realization of emission analysis, transportation statistics of Turkey in the last 10 years have been evaluated. In addition, different scenarios have been presented for the years 2030 and 2050. It is found that average emissions emitted from passenger cars in Turkey decrease by year, and the use of LPG and CNG in plug-in hybrid cars generates lower emissions in future scenarios.

Comparison of the clinical effects of two different doses (0. 05% and 0. 1%) of topical cyclosporine A in dry eyes with meibomian gland dysfunction / Comparação de efeitos clínicos de duas doses diferentes (0, 05% e 0, 1%) de ciclosporina A tópica em olhos secos com disfunção da glândula tarsal

ABSTRACT Objective: To compare the clinical efficacy of two different doses of topical cyclosporine A used in addition to artificial tears in the treatment of patients with meibomian dysfunction and secondary dry eye. Methods: Fifty patients aged 18 to 40 years, who presented to our clinic between June 2020 and June 2021 were included in our study. Patients were divided into two groups as Group A (topical cyclosporine A 0.05%) and Group B (topical cyclosporine A 0.1%). All the patients underwent a detailed ophthalmological examination, basal Ocular Surface Disease Index measurement, and Schirmer 1 and tear break-up time tests at all visits. Results: The mean age was 32±7.1 years in Group A and 30.7±8.5 years in Group B. In Group A, there were 15 women and ten men, and Group B consisted of 14 women and 11 men. There was no difference between the groups in terms of age and gender distribution (p>0.05). Schirmer 1 and tear break-up time results and Ocular Surface Disease Index score also did not significantly differ between the groups (p>0.05). Conclusion: Cyclosporine A 0.05% and 0.1% eye drops were both seen to be effective in managing dry eye disease in patients with meibomian gland dysfunction.

RESUMO Objetivo: Comparar a eficácia clínica de duas doses diferentes de ciclosporina A tópica utilizada além da lágrima artificial no tratamento de pacientes com disfunção da glândula tarsal e olho seco secundário. Métodos: No estudo, foram incluídos 50 pacientes com idades entre 18 e 40 anos, que se apresentaram em nossa clínica entre junho de 2020 e junho de 2021. Os pacientes foram divididos em dois grupos: Grupo A (ciclosporina A 0,05% tópica) e Grupo B (ciclosporina A 0,1% tópica). Todos os pacientes foram submetidos a um exame oftalmológico detalhado, medição basal do Índice de Doença da Superfície Ocular, e testes de Schirmer 1 e de tempo de ruptura em todas as visitas. Resultados: A idade média foi de 32±7,1 anos no Grupo A e 30,7±8,5 anos no Grupo B. No Grupo A, havia 15 mulheres e dez homens, e o Grupo B consistia de 14 mulheres e 11 homens. Não havia diferença significativa entre os grupos em termos de distribuição por idade e gênero (p>0,05). Os resultados do Schirmer 1 e do tempo de ruptura e do Índice de Doenças da Superfície Ocular também não apresentaram diferença significativa entre os grupos (p>0,05). Conclusão: Observou-se que os colírios de ciclosporina A 0,05% e 0,1% são eficazes no tratamento da síndrome do olho seco em pacientes com disfunção da glândula tarsal.

Retinal Microvascular Vessel Density Differences between Adult Athletes and Nonathletes.

SIGNIFICANCE: Regular physical activity may affect the neurovascular structures. Many studies have shown the positive effects of physical activity on ocular disorders such as glaucoma, retinopathy, and macular degeneration. Athletes were expected to have a better retinal vascular structure compared with the nonathletes. PURPOSE: This study aimed to evaluate the effects of regular physical activity on the retinal microvascular structure. METHODS: This observational and cross-sectional study was conducted between January and July 2020 with participants aged 20 to 35 years who had a visual acuity of ≥20/20, axial length of 22 to 24 mm, refractive defect spherical equivalent of ≤±1 D, and IOP of ≤21 mmHg. Updated AngioScan software (Navis version 1.8.0) of Nidek's RS-3000 Advance system was used to analyze the spectral-domain optical coherence tomography and optical coherence tomography angiography images. RESULTS: A total of 60 right eyes of 60 individuals were included in the study. Thirty subjects were in the athlete group, and 30 patients were in the nonathlete group. Sixteen of the individuals in the athlete group and 15 in the nonathlete group were women (P > .05). Retinal nerve fiber layer and ganglion cell complex thicknesses in all quadrants were thinner in nonathletes (P < .05). All of the Early Treatment Diabetic Retinopathy Study regions except central foveal subfield thickness were significantly higher in the athlete group (P < .05). In the nonathlete group, significantly reduced vessel densities of the superficial and deep capillary plexus and radial peripapillary capillary plexus, and the foveal avascular zone circularity index along with an increased foveal avascular zone perimeter and area were also detected (P < .05). CONCLUSIONS: Our study revealed that optical coherence tomography angiography measurements may be used in the determination of the effects of physical activity on retinal vascular structure changes.

Logistic Regression Model Using Scheimpflug-Placido Cornea Topographer Parameters to Diagnose Keratoconus.

PURPOSE: Diagnose keratoconus by establishing an effective logistic regression model from the data obtained with a Scheimpflug-Placido cornea topographer. METHODS: Topographical parameters of 125 eyes of 70 patients diagnosed with keratoconus by clinical or topographical findings were compared with 120 eyes of 63 patients who were defined as keratorefractive surgery candidates. The receiver operating character (ROC) curve analysis was performed to determine the diagnostic ability of the topographic parameters. The data set of parameters with an AUROC (area under the ROC curve) value greater than 0.9 was analyzed with logistic regression analysis (LRA) to determine the most predictive model that could diagnose keratoconus. A logit formula of the model was built, and the logit values of every eye in the study were calculated according to this formula. Then, an ROC analysis of the logit values was done. RESULTS: Baiocchi Calossi Versaci front index (BCVf) had the highest AUROC value (0.976) in the study. The LRA model, which had the highest prediction ability, had 97.5% accuracy, 96.8% sensitivity, and 99.2% specificity. The most significant parameters were found to be BCVf (p=0.001), BCVb (Baiocchi Calossi Versaci back) (p=0.002), posterior rf (apical radius of the flattest meridian of the aspherotoric surface in 4.5 mm diameter of the cornea) (p=0.005), central corneal thickness (p=0.072), and minimum corneal thickness (p=0.494). CONCLUSIONS: The LRA model can distinguish keratoconus corneas from normal ones with high accuracy without the need for complex computer algorithms.

Protection against experimental cisplatin-induced optic nerve toxicity using resveratrol: A rat model study.

AIM: To investigate the effects of resveratrol on oxidative stress and inflammation parameters and histological alterations in cisplatin-induced optic nerve damage in a mouse model. MATERIAL AND METHOD: Thirty-six albino Wistar male rats were divided into three groups as control, 5 mg/kg cisplatin-administered (Cis) and 5 mg/kg cisplatin + 25 mg/kg resveratrol-administered (Cis + Res) animals. At the end of the experimental period, the rats were sacrificed with high-dose (50 mg/kg) thiopental sodium, and their optic nerves were dissected. Malondialdehyde (MDA), total glutathione (tGSH), total oxidant status (TOS), total antioxidant status (TAS), tumour necrosis factor alpha (TNF-α), nuclear factor kappa B (NF-KB) levels, and histopathological findings were assessed using the optic nerve tissues. RESULTS: In the Cis + Res group, the MDA, TOS, OSI, TNF-a and NFK-B levels were significantly lower and the tGSH and TAS levels were significantly higher compared with the Cis group (P = 0.001). In histological evaluations, there were dilated and congested blood vessels, destruction, oedema, degeneration, haemorrhage, and proliferating capillaries indicating the presence of inflammation and damage only in the Cis-administered group. However, in the Cis + Res group, the histological findings were very similar to the healthy controls. CONCLUSION: Resveratrol is a promising neuroprotective agent for cisplatin-induced optic nerve toxicity with its anti-oxidant and anti-inflammatory effects. Further investigations are needed to evaluate the possible therapeutic effects on other optic nerve toxicities.

Comparison of Six Methods of Central Corneal Thickness Measurement in Healthy Eyes.

OBJECTIVES: Several methods of measuring central corneal thickness (CCT) have been compared, however, the data are still limited and conflicting. The aim of this study was to determine the agreement of CCT measurements performed in healthy eyes using ultrasound pachymetry (USP), non-contact tono/pachymetry, specular microscopy, biometry, Scheimpflug-based corneal topography, and optical coherence tomography (OCT). METHODS: All of the participants underwent a complete ophthalmological examination. The CCT of all of the eyes included was measured using 6 different methods. The agreement between the methods was analyzed using the mean difference and Bland-Altman analysis based on a 95% limits of agreement. RESULTS: A total of 64 patients with a mean age of 40.96±14.52 years (range: 20-78 years) were included in the study. The mean CCT value was 552.10±35.65 µm, 550.40±35.55 µm, 554.67±35.49 µm, 545.39±34.21 µm, 546.25±35.49 µm, and 552.64±33.59 µm using USP, non-contact tono/pachymetry, non-contact specular microscopy, biometry, Scheimpflug-based corneal topography, and OCT, respectively. The bias values determined by Bland-Altman plots were -1.70, -2.56, 6.71, 5.85, and -0.53 for tono/pachymetry, specular microscopy, biometry, topography, and OCT, respectively. OCT demonstrated the lowest bias compared to USP. The overall intraclass correlation coefficient was 0.961 (range: 0.945-0.974) with a 95% confidence interval. CONCLUSION: All of the CCT measurements obtained using non-contact tono/pachymetry, non-contact specular microscopy, biometry, Scheimpflug-based corneal topography, and OCT were consistent with the USP measurements of healthy controls. Larger prospective studies to determine the interchangeability of different methods for CCT measurements in pathological conditions are warranted.

Frequency of retinopathy of prematurity (ROP) in infants screened for ROP: two years follow-up results of a single center in Turkey.

AIM: The aim of this retrospective study was to determine the incidence of retinopathy of prematurity (ROP) in infants referred to our clinic for screening ROP. MATERIAL AND METHOD: The data of 729 infants who were referred to the ROP outpatient clinic of the Ophthalmology Unit of Erzincan Binali Yildirim University, Turkey between April 2018 and March 2020 were analyzed retrospectively. The gestational age and weight of the infants, stay in the neonatal intensive care unit, duration of oxygen therapy, and detailed ophthalmologic examination findings were recorded in the study. FINDINGS AND RESULTS: Of the 729 babies screened for ROP, 122 (16.7%) of them had ROP. Infants with gestational age of ≤28 weeks constitute 3.3% of all infants and ROP rate was significantly higher than infants with older gestational age (P < 0.001). There were 39 babies born under 1000 grams and ROP was present in 28 (71.8%) of these infants and the incidence of ROP was higher than infants with higher birth weight (P < 0.001). With the result of logistic regression analysis, gestational age (OR:0.592,95% CI:0.208-0.779,P < 0.001), stay in NICU (OR:0.998,95% CI:1.022-1.421,P = 0.001), and duration of oxygen (O2) therapy (OR:34.309, 95% CI:2.043-28.235,P = 0.004) were detected the independent risk factors for ROP. CONCLUSION: Although infants with ≤1000 grams gestational weight and ≤28 weeks gestational age are more likely to have ROP, it is clear that screening for all infants at risk, regardless of gestational weight and age, is very important in preventing ROP-related vision loss. In addition, it is also recommended to control the duration of staying in neonatal intensive care unit and oxygen therapy to as little as needed.

WHAT IS THE INCIDENCE OF RETINOPATHY OF PREMATURITY (ROP) IN 'BIG' BABIES?: RESULTS OF A RETROSPECTIVE MULTICENTER STUDY.

AIM: This study aims to determine the incidence of ROP and to investigate its prognosis among premature babies with a BW of ≥2000 g. MATERIAL AND METHOD: We retrospectively analyzed the data of 1004 babies with BW≥2000 g admitted to the ROP Diagnosis and Treatment Centers of X University Hospital and X Hospital between 2018 and 2019. Examination findings were recorded according to the Classification of Retinopathy of Prematurity guideline. We recorded the following information: GA, BW, type of delivery, oxygen therapy, age at the time of diagnosis (weeks), the location of ROP, the severity of ROP, vascular characteristics of ROP, treatment status, PMA, treatment modality, and retinal vascular development. RESULTS: The 2008 eyes of 1004 subjects were included in the study. Mean GA (SD) of subjects was 34.3 (1.3) weeks (range: 31-36) and mean BW (SD) was 2377.3 (244.2) g (range: 2000-3400). The 283 eyes of 144 patients (14.1%, 95% CI: [11.7-17.3%]) had been diagnosed with ROP. We evaluated the location of ROP and found that it was in Zone II in 279 of the 283 eyes and in Zone I in 4 eyes. We found that 213 of the 283 eyes had stage 1 ROP, 53 eyes had stage 2 ROP, and 17 eyes had stage 3 ROP. According to the international ROP classification, 17 eyes of 9 patients had Type 1 ROP, and 266 eyes of 135 patients had Type 2 ROP in the study. Seventeen eyes (0.85%, 95%CI: [0.62-1.36%]) required treatment. CONCLUSION: We conclude that the incidence of ROP in babies with BW≥2000 g is higher in Turkey compared to developed countries. It is important to include these babies in the screening program as they can develop advanced ROP requiring treatment.

Influences of Hypomagnesemia on Optic Nerve and Retinal Vascular Structure Determined Using Optical Coherence Tomography (OCT) Angiography.

Purpose: To evaluate the effects of low blood magnesium levels on the optic nerve, retina, and retinal vascular structure.Methods: This observational and cross-sectional study was conducted between June 2019 and May 2020 with participants aged 20-39 years, who had a visual acuity of ≥20/20, the axial length of 22-24.5 mm, refractive defect spherical equivalent of ≤±3D, and intraocular pressure of ≤21 mm Hg. All participants had a complaint of twitching in their eyes. The participants with normal serum magnesium levels constituted the control group, and patients with hypomagnesemia constituted the patient group. Updated AngioScan software (Navis ver. 1.8.0.) of Nidek's RS-3000 Advance system was used to analyze the spectral domain-optical coherence tomography (SD-OCT) and optical coherence tomography-angiography (OCT-A) images.Results: A total of 100 right eyes of 100 individuals was included in the study. The mean retinal nerve fiber layer (RNFL) thickness was 108.52 ± 12.46 µm in the control group, and 97.3 ± 9.7 µm in the hypomagnesemia group (P < .001). In the control group, the global superficial capillary plexus (SCP) and deep capillary plexus (DCP) vessel densities (VDs) were 41.92 ± 2.29, and 37.54 ± 3.83, respectively. In the patient group, the global SCP and DCP VDs were 37.66 ± 3.14, and 32.95 ± 5.57, respectively. The SCP and DCP VD percentages were significantly lower in the patient group. The mean foveal avascular zone (FAZ) area, perimeter and circularity index (CI) were 0.32 ± 0.13 mm2, 2.89 ± 0.59 mm, and 0.52 ± 0.09, respectively, for the control group and 0.38 ± 0.11 mm2, 2.99 ± 0.64 mm, and 0.38 ± 0.1, respectively, for the patient group. The FAZ area and perimeter were significantly higher (P = .013 and P = .001) and FAZ CI was significantly lower (P < .001) in the patients with hypomagnesemia.Conclusion: Our study revealed that OCT and OCT-A measurements may be used in the determination of the optic nerve and retinal vascular structure changes in hypomagnesemia.

Evaluation of the Optic Disc and Macula in Healthy Children Using Optical Coherence Tomography Angiography

Objectives: To perform the measurements of the optic disc and macula in healthy children using optical coherence tomography angiography (OCTA) in order to determine the normative data values and compare these by age, gender, spherical equivalent (SE), and axial length (AL). Materials and Methods: A total of 146 eyes belonging to 146 healthy children (74 girls, 72 boys) aged 6 to 16 years were included in this prospective study. Refraction and biometry measurements were performed. Retinal nerve fiber layer thickness (RNFLT), central macular volume, and central macular thickness (CMT) were measured by optical coherence tomography (OCT) after dilatation. Using the OCTA device, foveal avascular zone (FAZ) area, vascular density (VD) of the superficial capillary plexus (SCP) and deep capillary plexus (DCP) of the macula, and the VD of the radial peripapillary capillary plexus (RPCP) of the optic disc were recorded. Results: The mean age of the study group was 11.27±3 years, the mean AL was 23.39±1.18 mm and the mean SE was -1.31±1.61 diopters. The mean FAZ area was 0.3±0.09 mm2, the mean SCP-VD was 43.88±3.4%, the mean DCP-VD was 39.6±3.55%, and the mean RPCP-VD was 52.47±3.42%. When the relationship between the OCTA measurements and the SE and AL values were analyzed, there was no statistical significance (p>0.05). When age and OCTA measurements were compared, only DCP-VD values were found to significantly decrease with increasing age (p=0.015). There was no significant difference in OCTA measurements based on gender (p>0.05). Similarly, no statistical age-based differences were observed in RNFLT, CMV and CMT values (p>0.05). Conclusion: With its short procedure time and no dye requirement, OCTA can be safely used in the evaluation of the optic disc and macular perfusion in children. Determination of normative values in children will be useful in detecting pathologic changes in tissue in patients with retinal diseases.

The findings of corneal specular microscopy in patients with type-2 diabetes mellitus.

BACKGROUND: We aimed to compare the morphological characteristics of corneal endothelial cells in type 2 diabetic patients and age-matched healthy subjects by specular microscopy. We also aimed to determine the association of corneal morphological features with the general characteristics and laboratory data of diabetic patients, including disease duration, haemoglobin A1c (HbA1c) levels and urine albumin creatinine ratio. METHODS: A total of 195 diabetic patients and 100 healthy controls were enrolled in the study. All participants underwent a complete ophthalmological examination. Corneal endothelial measurements were performed using a noncontact specular microscopy. Laboratory data including serum fasting glucose, haemoglobin A1c levels, creatinine levels, and the urinary albumin-to-creatinine ratio were recorded. Diabetic patients were further subdivided into 3 groups according to the presence and stage of diabetic retinopathy. Specular microscopy findings and central corneal thickness of all patients were compared. RESULTS: The ECD and hexagonal cell ratio were significantly lower, while the average cell size, CV%, and central corneal thickness were determined to be significantly higher in diabetic patients than in healthy controls (p = 0.001). With the presence and advancement of diabetic retinopathy, the ECD and hexagonal cell ratio decreased, while the average cell size, CV%, and central corneal thickness increased. When correlation analysis was performed between corneal morphological features and laboratory data of diabetic patients, ECD showed a significant negative correlation with diabetes duration (p = 0.028). HbA1c levels, urinary albumin-creatinine ratio (p = 0.041), average cell size and CV showed a positive correlation with these parameters. CONCLUSION: In conclusion, keratopathy is an important complication of type 2 diabetes. With an increase in the stage of diabetic retinopathy, alterations in corneal findings also increased. In that respect, we can suggest that keratopathy should be evaluated more cautiously in diabetic patients.

Alterations in optical coherence tomography angiography findings in patients with high myopia.

PURPOSE: The aim of this study was to determine the macular changes using optical coherence tomography (OCT) and OCT-angiography (OCT-A) in eyes with high myopia. Determining the alterations in vascular structures can provide a clearer understanding of the pathophysiological mechanisms of this disease and help define new treatment options and preventive measures. MATERIALS AND METHODS: Ninety-two patients with high myopia (axial length ≥ 26 mm) and 70 control cases without any known systemic or ocular diseases were enrolled in this prospective study. One eye of each patient was included in the statistical analyses. RESULTS: Retinal nerve fiber layer (RNFL) thickness and Early Treatment Diabetic Retinopathy Study (ETDRS) macula map values were lower in myopia compared with the controls. Both superior and inferior ganglion cell complex (GCC) thicknesses were significantly thinner in the high myopia compared with the controls (p < 0.001). Regarding the OCT-A findings, although superficial or deep foveal avascular zones (FAZ) did not significantly differ between the two groups, the density values of superficial and deep microvessels were significantly lower in the high myopia group compared with the control cases. CONCLUSIONS: In patients with high myopia, with an increase in the axial length and a decrease in RNFL and GCC thicknesses, the vascular densities of the superficial and deep retina were reduced in the macular region.

Ophthalmologic Manifestations and Retinal Findings in Children with Down Syndrome.

PURPOSE: To evaluate ocular findings in children with Down syndrome and to compare with the healthy children group. METHODS: The study patients were divided into two groups as the diagnosed Down syndrome group and the control group. The study was designed as a prospective and single-center study in Istanbul University Faculty of Medicine Department of Ophthalmology. The study included 93 patients in the age range from 7 to 18 years, who applied to the ophthalmology department of our clinic in the period from July 2017 to June 2018. The study included the patients allocated into the control group and the Down syndrome patients allocated into the patient group, containing 49 and 44 participants, respectively. All patients underwent complete ophthalmologic examination with biomicroscopy. Autorefractometer measurements were performed in all patients, and the best corrected visual acuity (BCVA) was determined with the use of the Snellen chart. All patients underwent spectral domain optical coherence tomography (SD-OCT) measurements for central foveal retinal (CRT), subfoveal choroidal (CCT), and peripapillary retinal nerve fiber layer (pRNFL) thicknesses. RESULTS: The average CRT was 241.2 ± 25.7 microns in Down syndrome group and 219.4 ± 21.1 microns in the control group. There was a statistically significant difference between the groups in regards to CRT (p < 0.001). The average pRNFL values were 123.1 ± 15.4 microns in the Down syndrome group and 102.2 ± 8.7 microns in the control group (p < 0.001). The average pRNFL values were 123.1 ± 15.4 microns in the Down syndrome group and 102.2 ± 8.7 microns in the control group (. CONCLUSIONS: In the subjects with Down syndrome, the incidence of lens opacities, strabismus, and amblyopia was higher than the control group. CRT and pRNFL were thicker in the Down syndrome group than in control group. This may represent retinal developmental changes in the patients with Down syndrome.

Effects of two different contact lenses on ocular physiological parameters and tear function tests / Efeitos de duas lentes de contacto diferentes nos parâmetros fisiológicos oculares e nos testes de função lacrimal

Abstract Objective: To investigate the effects of two types of contact lenses made of two different types of silicone hydrogel material on ocular physiological parameters and tear function tests. Methods: The contact lenses with the appropriate diopters were supplied to the volunteering patients. The patients were evaluated before wearing the contact lenses (visit0:V0), at the first month(visit1:V1) and at the thirth month(visit2:V2) following their wear. At all visits a detailed biomicroscopic examination was done, ocular physiological variables were collected, the tear function tests were performed and the tear meniscus area (TMA) was visualized and measured with anterior segment optical coherence tomography (AS-OCT). Results: The results of Schirmer 1 test were 12.07 ± 1.51 [9-16] mm for the right eyes (samfilcon A group) and 12.09 ± 1.5 [9-16] mm for the left eyes (senofilcon A group) at V0. (p=0.950) At V2, the mean Schirmer 1 test results were 11.92±1.34 [9-15] mm in the samfilcon A group and 12.2±1.41 [9-16] mm in the senofilcon A group (p=0.239). The mean TMA dimensions in the AS-OCT images were 338.42±47.1 [241-401] microns in the samfilcon A group and 338.42±47.1 [241-401]microns in the senofilcon A group at V0. (p>0.05). At V2, the mean TMA dimensions were 337.2±45.53 [241-402] microns in thesamfilcon A group and 340.31±48.22 [240-411] microns in the senofilcon A group (p=0.728). Conclusions: Our study has demonstrated that contact lenses containing samfilcon A and senofilcon A silicone hydrogel material do not cause meaningful ocular surface problems.

Resumo Objetivo: Investigar os efeitos de dois tipos de lentes de contacto feitas de dois tipos diferentes de material de hidrogel de silicone nos parâmetros fisiológicos oculares e testes de função lacrimal. Métodos: As lentes de contacto com as dioptrias apropriadas foram fornecidas aos pacientes voluntários. Os pacientes foram avaliados antes do uso das lentes de contacto (visita0: V0), no primeiro mês (visita1: V1) e no terceiro mês (visita2: V2), após o uso destas. Em todas as visitas, foi realizado um exame biomicroscópico detalhado, as variáveis fisiológicas oculares foram recolhidas, os testes de função lacrimal foram realizados e a área do menisco lacrimal (TMA) foi visualizada e medida com tomografia de coerência óptica do segmento anterior (AS-OCT). Resultados: Os resultados do teste de Schirmer 1 foram 12,07 ± 1,51 [9-16] mm para os olhos direitos (grupo samfilcon A) e 12,09 ± 1,5 [9-16] mm para os olhos esquerdos (grupo senofilcon A) em V0. (p = 0,950) Em V2, os resultados médios do teste de Schirmer 1 foram 11,92 ± 1,34 [9-15] mm no grupo samfilcon A e 12,2 ± 1,41 [9-16] mm no grupo senofilcon A (p = 0,239). As dimensões médias do TMA nas imagens AS-OCT foram 338,42 ± 47,1 [241-401] mícrons no grupo samfilcon A e 338,42 ± 47,1 [241-401] mícrons no grupo senofilcon A em V0. (p> 0,05).> Em V2, as dimensões médias do TMA foram 337,2 ± 45,53 [241-402] mícrons no grupo samfilcon A e 340,31 ± 48,22 [240-411] mícrons no grupo senofilcon A (p = 0,728). Conclusões: O nosso estudo demonstrou que as lentes de contacto que contêm material de hidrogel de silicone de samfilcon A e senofilcon A não causam problemas significativos na superfície ocular.

Normative Data Assessment of Vessel Density and Foveal Avascular Zone Metrics Using AngioScan Software.

Purpose: To establish a normative database for macular and peripapillary vessel densities (VD) and foveal avascular zone (FAZ) metrics in healthy subjects with the new version of AngioScan software of RS-3000 Advance (Nidek Co, Ltd) optical coherence tomography angiography (OCT-A) device.Methods: The study design was prospective and cross-sectional. VDs of the SCP, deep capillary plexus (DCP), retinal peripapillary capillary plexus (RPCP) and FAZ area, perimeter and circularity index (CI) along with the structural OCT measurements were scanned by using the Nidek's RS-3000 Advance OCT-A device in healthy subjects. The new version of the AngioScan software was used for analytics. The relations between the OCT-A parameters with age, gender and OCT parameters were analyzed.Results: A total of 128 right eyes of 128 subjects (50% female) were included in this study. We divided subjects into 3 groups in accordance with age; 19-39 years to Group 1, 40-59 years to Group 2, >60 y. to Group 3. The mean SCP and DCP VDs were 41.25 ± 2.51% and 36.01 ± 5.07% respectively (P < .001). The DCP VD was significantly different between groups (P = .001). The mean FAZ area, perimeter and CI were 0.33 ± 0.12 mm2, 2.68 ± 0.6 mm and 0.47 ± 0.09 respectively. Only FAZ CI significantly differed between groups (P = .003). The FAZ area was significantly greater in female subjects than males (P = .025). The SCP and DCP VDs were inversely correlated with FAZ area and perimeter (P < .05).Conclusion: Our study provided for the first time the normative data of the recently updated AngioScan software of Nidek. Additional studies are needed to define pathological vascular changes in ocular and systemic diseases with this new software.

Evaluation of Maculopathy in Patients Using Hydroxychloroquine

Objectives: To determine length of hydroxychloroquine use and cumulative dose and evaluate the ocular effects by 10-2 central visual field test, microperimetry (MP), color fundus photography, optical coherence tomography (OCT), and fundus autofluorescence (FAF) in hydroxychloroquine users. Materials and Methods: Patients who used hydroxychloroquine continuously for at least 2 years for various connective tissue diseases were included in the study. A total of 300 eyes of 150 patients aged 19-78 years who were followed due to risk of developing hydroxychloroquine maculopathy in the Istanbul University Istanbul Faculty of Medicine Ophthalmology Department between the years 1995-2017 were evaluated. Best corrected visual acuity (BCVA), biomicroscopic, and fundoscopic examination were performed at all visits. MP, FAF, OCT, fundus photography, and central 10-2 visual field examinations were performed 3 times at 6-month intervals. Results: The mean age of patients was 48.9±10.8 years; 141 (94%) patients were female and 9 (6%) were male. The mean duration of hydroxychloroquine use was 10.5±6.4 (2-30) years. Fifty-six patients had been using the drug for 5 years or less. The mean cumulative drug dose was 754.7±447.2 (146-1825) g. Mean BCVA was 0.02±0.08 LogMAR at all follow-up visits (p=0.999). Mean MP values at the first, second, and third examinations were 14.07±3.24 dB, 14.18±3.35 dB, and 14.54±2.79 dB, respectively (p>0.05). Mean central macular thickness was 221.9±19.8 µm at initial examination, 221.8±19.9 µm at the second visit, and 221.8±19.8 µm at the final visit (p=0.113). There was a weak negative correlation between age and MP values at all three visits (visit 1: p=0.003, r=- 0.170; visit 2: p=0.001, r=-0.185, visit 3: p=0.011, r=-0.146). There was statistically significant relationship between MP values and hydroxychloroquine length of use and cumulative dose (p=0.027 and p=0.049, respectively). Duration of use was not associated with changes in 10/2 visual field (p=0.124). There were significant relationships between alterations in FAF and hydroxychloroquine length of use and cumulative dose (p=0.027 and p=0.049, respectively). Conclusion: FAF alterations were significantly associated with duration of hydroxychloroquine use and cumulative dose. As objective methods are more reliable, examinations such as FAF can be recommended as auxiliary methods in the follow-up and early detection of toxic maculopathy.