Lower Retinal Nerve Fiber Layer Thickness Research Articles

Retinal and peripapillary vascular density in episodic and chronic migraine cases without aura

BackgroundMigraine is a neurovascular disease that can cause ocular and systemic ischemic damage. Despite from aura, a limited number of studies have considered the effect of the chronic migraine in cases without aura. Our aim was to evaluate the differences in the retinal and optic disk microvasculature among episodic and chronic migraine cases without aura using optical coherence tomography angiography (OCTA) imaging. Methods45 cases with migraine, and 25 control subjects were included in this prospective, cross-sectional study. OCTA was performed at 3 × 3 mm and 6 × 6 mm of the macula and at 4.5 × 4.5 mm of the optic disk. Retinal nerve fiber layer (RNFL) thickness, ganglion cell complex thickness, and vessel densities of the optic nerve and macula were compared among the three groups: a control group, an episodic migraine without aura (EMWOA) group, and a chronic migraine without aura (CMWOA) group. ResultsIn EMWOA group, circumpapillary vascular density (cpVD) was not decreased significantly in any quadrants (all, p>0.05). Compared to the control group, CMWOA group had significantly lower RNFL thickness in superior-temporal quadrants (p = 0.002 and 0.006, respectively), while cpVD differed only in the temporal quadrant and temporal inferior sector (p = 0.002 and p = 0.009, respectively). ConclusionsTemporal peripapillary perfusion is valuable in the follow-up of chronic migraine cases. Longitudinal studies are needed to determine the place of OCTA in the follow-up of migraine.

Retinal Functional and Structural Neural Indices: Potential Biomarkers for the Monitoring of Cerebral Neurodegeneration: The Maastricht Study.

If retinal indices of neurodegeneration are to be biomarkers for the monitoring of cerebral neurodegeneration, it is important to establish whether potentially modifiable risk factors for dementia are associated with retinal neurodegenerative changes. To study associations of dementia risk factors with retinal sensitivity, an index of retinal neural function, and retinal nerve fiber layer (RNFL) thickness, an index of retinal neural structure. We used cross-sectional data from The Maastricht Study (up to 5,666 participants, 50.5% men, mean age 59.7), and investigated associations with regression analyses (adjusted for potential confounders). Most risk factors under study (i.e., hyperglycemia, unhealthy diet, lower cardiorespiratory fitness, smoking, alcohol consumption, and hypertension) were significantly associated with lower retinal sensitivity and lower RNFL thickness. Findings of this population-based study support the concept that retinal neural indices may be biomarkers for the monitoring of therapeutic strategies that aim to prevent early-stage cerebral neurodegeneration and, ultimately, dementia.

Refractive status and retinal morphology in children with a history of intravitreal ranibizumab for retinopathy of prematurity.

This study investigated the characteristics of refractive status, visual acuity, and retinal morphology in children with a history of receiving intravitreal ranibizumab for retinopathy of prematurity (ROP). Children 4-6years of age were enrolled and divided into the following four groups: group 1, children with a history of ROP who had been treated with intravitreal ranibizumab; group 2, children with a history of ROP who had not received any treatment; group 3, premature children without ROP; and group 4, full-term children. Refractive status, peripapillary retinal nerve fiber layer (RNFL), and macular thickness were measured. A total of 204 children were enrolled. In group 1, myopic shift was not noted, but poorer best corrected visual acuity (BCVA) and shorter axial length were observed. Significantly lower peripapillary RNFL thickness in the average total and superior quadrant, higher central subfield thickness, lower parafoveal retinal thickness in average total, superior, and nasal and temporal quadrants were observed in group 1 than in the other groups. The poor BCVA in patients with ROP was correlated with the lower RNFL thickness in the superior quadrant. Conclusion: Children with a history of type 1 ROP treated with ranibizumab did not show a myopic shift but did show abnormal retinal morphology and the poorest BCVA among all groups. We suggest that pediatric ophthalmologists should always pay attention to visual development in patients with ROP with a history of intravitreal ranibizumab. What is Known: • Anti-VEGF is efficiently and widely used in the treatment of type 1 retinopathy of prematurity (ROP), and different anti-VEGF agents are associated with different prevalence of myopia. • Patients with ROP who receive treatment such as laser therapy or cryotherapy have abnormal macular development and retinal nerve fiber layer (RNFL) thickness. What is New: • Children with a history of ROP treated with intravitreal ranibizumab did not show a myopic shift but did show poor BCVA at 4-6years of age. • Abnormal macular morphology and lower peripapillary RNFL thickness were found in these children.

Association of Optic Nerve Head and Macular Optical Coherence Tomography Measures With Glaucoma-Related Disability.

Optical coherence tomography (OCT) estimated retinal nerve fiber layer (RNFL) thickness associated with glaucoma-related disability independent of the visual field (VF) damage and thus may provide additional patient-relevant disability information beyond what is captured by standard VF testing. To examine whether OCT metrics [peripapillary RNFL thickness and macular ganglion cell/inner plexiform layer (GCIPL) thickness] are associated with quality of life (QoL) measures and additional disability metrics, and whether these associations are independent of VF damage. In this cross-sectional study, 156 patients with glaucoma or suspected glaucoma received VF testing and OCT scans to measure RNFL and GCIPL thickness. QoL was assessed using the Glaucoma Quality-of-Life 15 and additional disability measures including fear of falling, reading speed, and steps per day were assessed. Multivariable regression models adjusting for relevant covariates tested whether RNFL or GCIPL thickness from the less-impaired eye were associated with disability measures and whether associations were independent of VF damage. Greater VF damage is associated with worse QoL (95% CI=0.4-1.4; P <0.001) and slower reading speed (CI=-0.06 to -0.02; P <0.001). Lower RNFL and GCIPL thicknesses were associated with lower QoL scores, but not with QoL scores or other disability metrics after correcting for VF damage. However, post hoc analyses in patients with better eye thicknesses between 55 and 75µm demonstrated associations between lower RNFL thickness and worse QoL (CI=-2.2 to -0.1; P =0.04) and greater fear of falling (CI=-6.1 to -0.4; P =0.03) even after accounting for VF damage. No such associations were observed for GCIPL thickness. OCT RNFL, but not GCIPL, thickness is associated with multiple disability measures independent of VF damage severity.

Retinal Blood Vessel Analysis Using Optical Coherence Tomography (OCT) in Multiple Sclerosis

Background: Both greater retinal neurodegenerative pathology and greater cardiovascular burden are seen in people with multiple sclerosis (pwMS). Studies also describe multiple extracranial and intracranial vascular changes in pwMS. However, there have been few studies examining the neuroretinal vasculature in MS. Our aim is to determine differences in retinal vasculature between pwMS and healthy controls (HCs) and to determine the relationship between retinal nerve fiber layer (RNFL) thickness and retinal vasculature characteristics. Methods: A total of 167 pwMS and 48 HCs were scanned using optical coherence tomography (OCT). Earlier OCT scans were available for 101 pwMS and 35 HCs for an additional longitudinal analysis. Segmentation of retinal vasculature was performed in a blinded manner in MATLAB's optical coherence tomography segmentation and evaluation GUI (OCTSEG) software. Results: PwMS has fewer retinal blood vessels when compared to HCs (35.1 vs. 36.8, p = 0.017). Over the 5.4 year follow up, and when compared to HCs, pwMS has a significant decrease in number of retinal vessels (average loss of -3.7 p = 0.007). Moreover, the total vessel diameter in pwMS does not change when compared to the increase in vessel diameter in the HCs (0.06 vs. 0.3, p = 0.017). Only in pwMS is there an association between lower RNFL thickness and fewer retinal vessel number and smaller diameter (r = 0.191, p = 0.018 and r = 0.216, p = 0.007). Conclusions: Over 5 years, pwMS exhibit significant retinal vascular changes that are related to greater atrophy of the retinal layers.

Retinal Vessel Density and Retinal Nerve Fiber Layer Thickness: A Prospective Study of One-Year Follow-Up of Patients with Parkinson's Disease.

This study aims to compare the superficial vascular density from the macular region and the retinal nerve fiber layer (RNFL) thickness from the optic disc region between Parkinson's disease (PD) patients and controls. We enrolled 56 idiopathic PD patients, totaling 86 eyes (PD group), and 45 sex- and age-matched healthy individuals, amounting to 90 eyes (control group). All subjects underwent examination using Zeiss wide-field vascular optical coherence tomography (OCT) (Cirrus HD-OCT 5000 Carl Zeiss, Germany), with a scanning range of 3 mm × 3 mm. We divided the images into two concentric circles with diameters of 1 mm and 3 mm at the macular fovea's center. Patients with PD were evaluated during their "off" phase using the Unified Parkinson's Disease Rating Scale III (UPDRS-III) and the Hoehn-Yahr scale (H-Y scale) to assess disease severity. The PD group exhibited significantly lower RNFL thickness (106.13±12.36 μm) compared to the control group (115.95±11.37 μm, P < 0.05). Similarly, the superficial retinal vessel length density was significantly lower in the PD group (20.7 [19.62, 22.17] mm-1) than in the control group (21.79±1.16 mm-1, P < 0.05). Correlation analysis revealed a negative correlation between RNFL thickness and UPDRS III score (rs=-0.036, P=0.037), and RNFL thickness tended to decrease with increasing severity of movement disorders. However, during the 6 and 12-month follow-up of some PD patients, we observed no progressive thinning of the RNFL or decreased superficial vascular density. PD patients show retinal structural damage characterized by RNFL thinning and reduced retinal vessel length density. However, RNFL thickness did not correlate with vascular density nor did it decrease with the disease's progression.

Characterization of Retinal Nerve Fiber Layer Thickness in a Cohort with Glutamic Acid Decarboxylase 65 and Glycine Receptor Autoimmunity

Objective To describe the retinal nerve fiber layer (RNFL) with the demographic and clinical profile in patients with glutamic acid decarboxylase 65 (GAD65) and glycine receptor (GlyR) neurological autoimmunity. Background GAD65 and GlyR autoimmunity can cause a wide range of clinical phenomena, including stiff-person spectrum disorder (SPSD) and epilepsy. Both GAD65, through γ-aminobutyric acid-ergic neurons, and GlyR interact in the retina. Optical coherence tomography (OCT) has previously been used in a variety of neurological disorders to establish baseline characteristics and monitor disease course. This presents a noninvasive opportunity to evaluate for a biomarker that may assist with the treatment of these rare but debilitating disorders. Design/Methods OCT measures of RNFL by sectors were studied in patients with GAD65 and GlyR neurological autoimmunity and compared to that of 148 healthy control eyes. Patients' baseline characteristics were also reviewed retrospectively from medical records. Results Of the 14 patients included in this study, 12 patients were female, and the mean age was 52.6 ± 16.8 (22-79) years when OCT was performed. Ten had GAD65 autoimmunity and 4 had GlyR autoimmunity. Patients with GAD or GlyR autoimmunity showed lower RNFL thickness in multiple sectors compared to the healthy control group. This result was most apparent in the anti-GAD65 antibody subgroup. Eleven patients had SPSD, one patient had epilepsy, and two had non-specific symptoms. Conclusions This study provides insight into baseline RNFL thickness in a group with GAD65 and GlyR autoimmunity, two conditions that may produce varied symptoms. While limited by sample size, RNFL thinning was seen in the GAD65 and GlyR autoimmunity groups, and it was most evident in the anti-GAD65 subgroup. This provides a baseline characterization and suggests that future studies should be conducted to determine the utility of OCT as a biomarker for these conditions.

Evaluation of retinal nerve fiber layer thickness in children with autism spectrum disorders

BackgroundThe study compared retinal nerve fiber layer (RNFL) thickness, macular thickness, and macular volume of children with autism spectrum disorder (ASD) to those of healthy control group and correlated the RNFL thickness with symptom severity in children with ASD. MethodForty children between the ages of 7 and 12 with normal intelligence levels and who were diagnosed with ASD as per DSM-5 were included in the ASD group. The control group consisted of healthy children, who were matched with subjects in the ASD group in terms of age and gender. The Autism Behavior Checklist (ABC) and Childhood Autism Rating Scale (CARS) were used to evaluate the severity of the disease in the cases diagnosed with ASD. The RNFL, macular thickness, and macular volume of all participants were measured optical coherence tomography (OCT). ResultsThe temporal, temporal superior, nasal superior, temporal inferior, and global RNFL thicknesses were significantly lower in the ASD group than in the control group. There was no correlation between the RNFL thickness and ASD symptom severity. The macular thickness and volume were not significantly different between the groups. ConclusionOur data suggest that lower RNFL thickness may relate to atypical brain development in the ASD, and this can be measured in the retina.

Peripapillary and Macular Vascular Density in Patients With Preperimetric and Early Primary Open Angle Glaucoma.

Decreased circumpapillary vascular density (cpVD) and average retinal nerve fiber layer (RNFL) thickness were detected at different locations in eyes with preperimetric glaucoma (PPG). Although RNFL loss was more prominent in preperimetric eyes, in early glaucoma, both cpVD and RNFL thickness showed comparable diagnostic ability. To evaluate changes in circumpapillary and macular vascular density and investigate correlations between vascular and structural parameters in PPG and early glaucoma. This cross-sectional study included a total of 27 patients with PPG in 1 eye and early primary open angle glaucoma in the fellow eye, as well as a control group consisting of 27 eyes of 27 healthy volunteers. All subjects underwent optical coherence tomography angiography (OCTA) imaging. RNFL and macular ganglion cell complex measurements were obtained simultaneously with vascular parameters by AngioVue OCTA using the single-scan protocol. cpVD was examined in 8 sectors. Diagnostic accuracy was evaluated using the area under the receiver operating characteristic curve. In preperimetric eyes, average RNFL thickness and whole-image vessel density had comparable diagnostic performance (area under the receiver operating characteristic curve =0.853 and 0.753, respectively). Compared with the control group, PPG eyes had significantly lower RNFL thickness in all quadrants (P<0.001-0.003) except for the temporal quadrant, whereas cpVD differed only in the nasal inferior and nasal superior sectors (P=0.001 and 0.041, respectively). In early glaucoma eyes, cpVD differed significantly from controls in all sectors except for the inferotemporal, temporal inferior, and temporal superior sectors, whereas perifoveal macular vascular parameters differed in all quadrants (all P<0.05). cpVD was strongly correlated with RNFL thickness in the superior, nasal, and temporal quadrants (r=0.664, 0.698, and 0.649, respectively, P<0.001) and moderately correlated in the inferior quadrant (r=0.450, P<0.001). Although RNFL involvement is valuable in the diagnosis and follow-up of PPG, the change in nasal cpVD has an important place in these patients. The role of macular vascular parameters and macular ganglion cell complex in glaucoma follow-up becomes important in early glaucoma. Longitudinal studies are needed to determine the place of OCTA in the diagnosis and follow-up of glaucoma.

Association of Inner Retinal Thickness with Prevalent Dementia and Brain Atrophy in a General Older Population: The Hisayama Study.

PurposeTo assess the association of inner retinal thickness with prevalent dementia and regional brain atrophy in a general older population of Japanese.DesignPopulation-based, cross-sectional study.ParticipantsA total of 1078 residents aged 65 years or older who participated in an eye examination, a comprehensive survey of dementia, and brain magnetic resonance imaging scanning in 2017.MethodsThe thicknesses of the inner retinal layers, namely, the ganglion cell-inner plexiform layer (GC-IPL) and retinal nerve fiber layer (RNFL)—were measured by swept-source OCT (SS-OCT). The association of these retinal thicknesses with the risk of the presence of dementia was estimated using restricted cubic splines and logistic regression models. Regional brain volumes were estimated separately by applying 2 different methods: voxel-based morphometry (VBM) and analysis by FreeSurfer software. The associations of GC-IPL and RNFL thickness with each brain regional volume were analyzed using multiple regression analysis.Main Outcome MeasurePrevalent dementia and regional brain atrophy.ResultsAmong the study participants, 61 participants (5.7%) were diagnosed with dementia. The likelihood of the presence of dementia significantly increased with lower GC-IPL thickness after adjusting for potential confounders (odds ratio, 1.62 [95% confidence interval, 1.30–2.01] per 1 standard deviation decrement in the GC-IPL thickness), but no significant association was observed with RNFL thickness. In the VBM analyses with the multivariable adjustment, lower GC-IPL thickness was significantly associated with lower volume of known brain regions related to cognitive functions (i.e., the hippocampus, amygdala, entorhinal area, and parahippocampal gyrus) and visual functions (i.e., the cuneus, lingual gyrus, and thalamus). Meanwhile, the volume of the thalamus significantly decreased with lower RNFL thickness, but none of the brain regions related to cognitive function exhibited a volume change in association with RNFL thickness. The sensitivity analysis using FreeSurfer analysis also showed that lower GC-IPL thickness was significantly associated with lower regional brain volume/intracranial volume of the hippocampus, amygdala, cuneus, lingual gyrus, and thalamus.ConclusionsOur findings suggest that the measurement of GC-IPL thickness by SS-OCT, which is a noninvasive, convenient, and reproducible method, might be useful for identifying high-risk individuals with dementia.

Association of Retinal Nerve Fiber Layer Thickness, an Index of Neurodegeneration, With Depressive Symptoms Over Time

Whether neurodegeneration contributes to the early pathobiology of late-life depression remains incompletely understood. To investigate whether lower retinal nerve fiber layer (RNFL) thickness, a marker of neurodegeneration, is associated with the incidence of clinically relevant depressive symptoms and depressive symptoms over time. This is a population-based cohort study from the Netherlands (The Maastricht Study) with baseline examination between 2010 and 2020 and median (IQR) follow-up of 5.0 (3.0-6.0) years. Participants were recruited from the general population. Individuals with type 2 diabetes were oversampled by design. Data analysis was performed from September 2020 to January 2021. RNFL, an index of neurodegeneration, assessed with optical coherence tomography. Depressive symptoms were assessed with the Patient Health Questionnaire (PHQ)-9 (continuous score, 0-27) at baseline and over time via annual assessments. The presence of clinically relevant depressive symptoms was defined as a PHQ-9 score of 10 or higher. We used data from 4934 participants with depressive symptoms over time (mean [SD] age, 59.7 [8.4] years; 2159 women [50.8%]; 870 had type 2 diabetes [20.5%]). Lower RNFL thickness was associated with higher incidence of clinically relevant depressive symptoms (per 1 SD, hazard ratio 1.11; 95% CI, 1.01-1.23) and more depressive symptoms over time (per 1 SD, rate ratio, 1.04; 95% CI, 1.01-1.06), after adjustment for demographic, cardiovascular, and lifestyle factors. The findings of this study suggest that lower RNFL thickness is associated with higher incidence of clinically relevant depressive symptoms and more depressive symptoms over time. Hence, neurodegeneration may be associated with the early pathobiology of late-life depression.

Evaluation of retinal nerve fiber layer thickness measured by (OCT) optical coherence tomography in patients with multiple sclerosis (MS)

Objective: The aim of this study is to evaluate the retinal nerve fiber layer (RNFL) thickness by optical coherence tomography (OCT) in Syrian patients with MS and diseases- free controls and to assess this thickness in MS-ON and MS-NON, and assess the relationship between RNFL thickness Expanded Disability Status Scale (EDSS) score. Although there are many similar studies to evaluate role of OCT at MS patients in different countries and many races,but this study is the first one of using OCT at MS patients in our country. Methods: This study (cross sectional ,case- control) was carried out at Tishreen University Hospital in Latakia. A total of 112 eyes from 56 individuals with an age range from 22 to 43 years were studied. twenty -six patients with definite MS, Diagnosis of MS was based on the MacDonald criteria.The disease-free controls were matched for age and gender (n=30; 60eyes). Retinal nerve fiber layer thickness was measured using optical coherence tomography (Spectralis OCT - Heidelberg Engineering), and gathering information about past ON history since more than 6 months and EDSS. Results: There were statistically Significant differences (p=0.0001) between both groups (case- control) were observed in OCT parameters (average, and all sectors especially temporal and superior sector) with lower RNFL thickness in the MS group (MS-ON,MS-NON).There were statistically significant differences (p=0.0001) between MS-ON (n = 20 eyes) and MS-NON (n = 32eyes) for all RNFL parameters measured by OCT, with lower RNFL thickness in (MS-ON).There were statistically significant inverse correlations was observed between average RNFL thickness and neurologic impairment (Expanded Disability Status Scale) (r=- 0.6، P=0.0001) and all sectors especially in temporal and superior quadrants (r=-7 , P=0.0001). Conclusions: OCT seems to be a reproducible test to detect axonal loss of ganglion cells in MS (RNFL). Further and larger longitudinal prospective studies would be valuable to assess the evolution over time of the RNFL measurements in Syrian MS patients.

Optical Coherence Tomography Angiography and Structural Analyses of the Pale Optic Discs: Is It Possible to Differentiate the Cause?

ABSTRACT Introduction: To compare the optic nerve head (ONH) structure and microvasculature in patients with optic atrophy due to non-arteritic anterior ischemic optic neuropathy (NAION), compressive optic neuropathy (CON), methanol-induced optic neuropathy (MION), and traumatic optic neuropathy (TON) using optical coherence tomography angiography. Methods: In this comparative, cross-sectional study, 32 eyes with NAION, 18 eyes with CON, 32 eyes with MION, 23 eyes with TON, and 55 normal eyes were enrolled. Radial peripapillary capillary (RPC) vessel density, peripapillary retinal nerve fiber layer (RNFL) thickness, disc area, cup volume, and cup/disc area ratio were obtained using the RTVue XR Avanti system (Optovue Inc., Fremont, CA, USA). Results: RPC vessel density and peripapillary RNFL thickness in all patients were significantly lower than normal subjects. A positive correlation was found between the RPC vessel density and peripapillary RNFL thickness in normal subjects and all study groups. The positive correlation between the inside and outside disc RPC vessel density was only found in the NAION (r = 0.36, P = .042) and MION (r = 0.42, P = .018) groups. No significant difference was found among the groups in terms of peripapillary and inside disc vascular densities (all P > .05). Disc area and cup volume in patients with MION was larger than the values in patients with NAION (P = .018) and TON (P = .044) and normal subjects (P = .015). The discriminating features among the study groups were the larger cup volume and cup/disc area ratio in patients with MION, and lower RNFL thickness in patients with TON. Conclusions: There was a positive correlation between the RNFL thickness and peripapillary RPC vessel density regardless of the cause of optic disc pallor. Structural evaluation of the ONH seems to be a better way to differentiate the cause of optic nerve head atrophy than the microangiographic changes.

The Relationship Between Retinal Nerve Fiber Layer Thickness and Clinical Symptoms of Alzheimer's Disease.

Background/Aim: Retinal nerve fiber layer (RNFL) thickness (RT), which can reflect the status of the retinal optic nerve cells, may be affected in patients with Alzheimer's disease (AD). There are few studies on the correlation of RT of patients with AD (AD-RT) with clinical symptoms of various cognitive domains, neuropsychiatric symptoms, and activities of daily living (ADL). This study is to investigate the relationships between RT and the abovementioned clinical symptoms of AD.Methods: A total of 96 patients with AD were included in this study. RT was measured in these patients using optical coherence tomography (OCT). Demographic variables, RT, and clinical symptoms were compared between the normal and the abnormal AD-RT groups. Clinical symptoms, including cognitive symptoms, neuropsychiatric symptoms, and ADL, were evaluated using a series of rating scales.Results: The relationships between RT and cognitive symptoms scores were analyzed in patients with AD. Reduced RT was found in 54.4% of patients with AD. The average RT, RT of the superior 1/2 quadrant, and RT of the inferior 1/2 quadrant of both eyes were all significantly decreased in the abnormal AD-RT group (p < 0.001). Overall cognitive function and performance in multiple cognitive domains, including memory, language, attention, and executive function, were also significantly impaired in the abnormal AD-RT group (p < 0.05). For lower RT value, the global cognitive function and the performance in multiple cognitive domains were worse. ADL was significantly compromised in patients with AD having lower RT values (p < 0.05).Conclusions: Lower RT value appear to be correlated with cognitive impairment, and RT may be an indicator of cognitive decline in patients with AD. Further studies are required to confirm our findings.

Study of correlation between stereopsis and retinal nerve fiber layer thickness in cases of glaucoma

BackgroundGlaucoma is an important and common optic neuropathy characterized by progressive loss of retinal ganglion cells and associated morphological changes to the optic nerve and retinal nerve fiber layer (RNFL). The most common assessment of visual function in glaucoma uses perimetric measurements of visual sensitivity. Only few studies have evaluated the binocular function in patients with glaucoma. This study was taken up to establish the correlation of RNFL thickness, in glaucoma, with near and distance stereopsis. MethodsThis pilot, cross-sectional observational study included 100 diagnosed cases of glaucoma and 100 normal participants as controls, studied over a period of one year. The records of all the participants were checked, and only established cases of glaucoma after fulfilling the inclusion and exclusion criteria were included. Analysis of the RNFL using spectral-domain optical coherence tomography was carried out. All the participants were thereafter evaluated for stereoacuity by near (at 40 inches) and distance (at 3 meter) Randot stereoacuity charts. ResultsThere was a negative correlation between the RNFL thickness and the absolute value of streoacuity (-0.303 for distance versus -0.101 for near in cases and -0.308 for distance and -0.416 for near in control group), decreasing the actual functional stereoacuity, therefore the cases with lower RNFL thickness had lower stereoacuity both for distance and near, however it was statistically significant only for distance (p=0.002). ConclusionFunctional aspects, such as stereoacuity, may also be affected in the glaucoma because of decrease in RNFL thickness. Therefore, binocular status should also be evaluated in cases of glaucoma.

Swept-source optical coherence tomography analysis in asthmatic children under inhaled corticosteroid therapy

Purpose: To evaluate retinal nerve fiber layer thickness (RNFLT), ganglion cell layer thickness (GCLT), subfoveal choroidal thickness (SFCT), and central retinal thickness (CRT) in asthmatic children who were under inhaled corticosteroid treatment by using Swept-Source Optical Coherence Tomography (SS-OCT).Material and methods: Fifty-three children were prospectively analyzed in the study. Group 1 included 31 asthmatic children and group 2 included 22 healthy children. Asthmatic children received a dose 250 μg daily of inhaled fluticasone propionate (Flexotide, GlaxoSmithKline, Middlesex, UK). Allergy parameters including, exposure to smoke, eosinophil count, percentage of eosinophils, immunoglobuline (Ig) E levels, number of asthma attacks, number of sensitivity to allergens and follow-up time were recorded. The RNFLT, GCLT, SFCT, and CRT were analyzed with SS-OCT and the data were compared between the groups.Results: There were 13 girls (41.9%) and 18 boys (58.1%) in group 1 and 13 girls (59.1%) and 9 boys (40.9%) in group 2 (p = 0.22). The mean age was 9.3 ± 2.2 years in group 1 and 9.9 ± 1.5 years in group 2 (p = 0.08). The mean CRT (239.26 ± 34.56 µm versus 226.82 ± 26.23 µm, p = 0.22) and mean SFCT (273.97 ± 40.95 µm versus 280.41 ± 32.78 µm, p = 0.54) did not significantly differ between the groups. The superior, inferior, and average RNFLT were significantly lower in group 1 than group 2 (p < 0.05). There were significant correlations between total corticosteroid dose and RNFLT (p < 0.05) and between IgE levels and GCLT (p < 0.05).Conclusions: The SS-OCT revealed that asthmatic children under inhaled corticosteroid treatment have lower RNFLT than healthy subjects.

Clinical and genetic determinants of chronic visual pathway changes after methanol - induced optic neuropathy: four-year follow-up study

Context: Methanol poisoning induces acute optic neuropathy with possible long-term visual damage.Objective: To study the dynamics and key determinants of visual pathway functional changes during 4 years after acute methanol poisoning.Methods: A total of 42 patients with confirmed methanol poisoning (mean age 45.7 ± 4.4 years) were examined 4.9 ± 0.6, 25.0 ± 0.6, and 49.9 ± 0.5 months after discharge. The following tests were performed: visual evoked potential (VEP), retinal nerve fiber layer (RNFL) measurement, brain magnetic resonance imaging (MRI), complete ocular examination, biochemical tests, and apolipoprotein E (ApoE) genotyping.Results: Abnormal VEP P1 latency was registered in 18/42 right eyes (OD) and 21/42 left eyes (OS), abnormal N1P1 amplitude in 10/42 OD and OS. Mean P1 latency shortening during the follow-up was 15.0 ± 2.0 ms for 36/42 (86%) OD and 14.9 ± 2.4 ms for 35/42 (83%) OS, with maximum shortening up to 35.0 ms. No significant change of mean N1P1 amplitude was registered during follow-up.A further decrease in N1P1 amplitude ≥1.0 mcV in at least one eye was observed in 17 of 36 patients (47%) with measurable amplitude (mean decrease −1.11 ± 0.83 (OD)/−2.37 ± 0.66 (OS) mcV versus −0.06 ± 0.56 (OD)/−0.83 ± 0.64 (OS) mcV in the study population; both p < .001).ApoE4 allele carriers had lower global and temporal RNFL thickness and longer initial P1 latency compared to the non-carriers (all p < .05). The odds ratio for abnormal visual function was 8.92 (3.00–36.50; 95%CI) for ApoE4 allele carriers (p < .001). The presence of ApoE4 allele was further associated with brain necrotic lesions (r = 0.384; p = .013) and brain hemorrhages (r = 0.395; p = .011).Conclusions: Improvement of optic nerve conductivity occurred in more than 80% of patients, but evoked potential amplitude tended to decrease during the 4 years of observation. ApoE4 allele carriers demonstrated lower RNFL thickness, longer P1 latency, and more frequent methanol-induced brain damage compared to non-carriers.

Macular Pigment and Visual Function in Patients With Glaucoma: The San Diego Macular Pigment Study.

PurposeAlthough recent studies have shown that macular pigment (MP) is significantly lower in glaucoma patients, this relationship merits further investigation.MethodsThis cross-sectional study included 85 glaucoma patients and 22 controls. All subjects had standard automated perimetry (SAP) and retinal nerve fiber layer (RNFL) thickness measurements. Intake of lutein (L) and zeaxanthin (Z) was estimated using a novel dietary screener. The Heidelberg Spectralis dual-wavelength autofluorescence (AF) technology was employed to study the relationship between MP and glaucoma. The association between MP volume and glaucoma was investigated using linear regression models accounting for potential confounding factors.ResultsGlaucoma patients had significantly worse SAP mean deviation (MD) and lower RNFL thickness in the study eye compared to control subjects (P < 0.001 for both). MP (volume) was comparable between groups (P = 0.436). In the univariable model, diagnosis of glaucoma was not associated with MP volume (R2 = 1.22%; P = 0.257). Dietary intake of L and Z was positively and significantly related to MP in the univariable (P = 0.022) and multivariable (P = 0.020) models.ConclusionsThese results challenge previous studies that reported that glaucoma is associated with low MP. Dietary habits were found to be the main predictor of MP in this sample. Further research is merited to better understand the relationship between glaucoma, MP, and visual performance in these patients.

In vivo optic nerve head mechanical response to intraocular and cerebrospinal fluid pressure: imaging protocol and quantification method

This study presents a quantification method for the assessment of the optic nerve head (ONH) deformations of the living human eye under acute intraocular pressure (IOP) elevation and change of cerebrospinal fluid pressure (CSFP) with body position. One eye from a brain-dead organ donor with open-angle glaucoma was imaged by optical coherence tomography angiography during an acute IOP and CSFP elevation test. Volumetric 3D strain was computed by digital volume correlation. With increase in IOP the shear strain consistently increased in both sitting and supine position (p < 0.001). When CSFP was increased at constant IOP by changing body position, a global reduction in the ONH strain was observed (−0.14% p = 0.0264). Strain in the vasculature was significantly higher than in the structural tissue (+0.90%, p = 0.0002). Retinal nerve fiber layer (RNFL) thickness strongly associated (ρ = −0.847, p = 0.008) with strain in the peripapillary sclera (ppScl) but not in the retina (p = 0.433) and lamina (p = 0.611). These initial results show that: CSFP independently to IOP modulates strain in the human ONH; ppScl strains are greater than strains in lamina and retina; strain in the retinal vasculature was higher than in the structural tissue; In this glaucoma eye, higher ppScl strain associated with lower RNFL thickness.

Structure and Function Relationship of Activated Retinal Glia in Primary Open-Angle Glaucoma Patients.

Purpose To evaluate clinically activated retinal astrocytes and Müller cells (ARAM) regarding retinal sensitivity and retinal nerve fiber layer (RNFL) thickness in primary open-angle glaucoma (POAG). Methods Central visual field (VF; i.e., retinal sensitivity) was measured with a custom-made macular pattern by microperimetry and correlated with the presence (ARAM+) or absence (ARAM−) of ARAM on red-free fundus photography and with the corresponding RNFL by optical coherence tomography (OCT). Results In the eyes of POAG patients, ARAM+ had overall a significantly lower retinal sensitivity (ARAM+: 7.34 dB, ARAM−: 11.9 dB; p < 0.001) and lower RNFL thickness in the inferior peripapillary quadrants compared to ARAM− (RNFL superior: ARAM+ 74.2 μm, ARAM− 77.5 μm; RNFL temporal: ARAM+ 46.8 μm, ARAM− 53.0 μm, p < 0.001; and RNFL inferior: ARAM+ 63.2 μm, ARAM− 73.1 μm, p < 0.001). Within the same eye, ARAM+ showed a lower retinal sensitivity compared to ARAM− ([ARAM− (11.13 dB)] − [ARAM+ (9.56 dB) = 1.57 dB; p = 0.25). The proportion of ARAM+ per eye correlated strongly with reduced retinal light sensitivity (p = 0.02), corresponding lower peripapillary RNFL thickness (p = 0.02), and lower RNFL temporal quadrant thickness (p < 0.01), but not with greater age (p = 0.45). Conclusion ARAM was more frequently identified in the eyes with a lower retinal sensitivity and peripapillary RNFL thickness and may be a clinical sign in the macula for an advanced stage of POAG.