Total Retinal Nerve Fiber Layer Research Articles

Retinal morphology and microvasculature density alterations in generalized anxiety disorders

Purpose This study evaluates morphological alterations in the macula and peripapillary regions of patients with Generalized Anxiety Disorder (GAD) using optical coherence tomography (OCT) and OCT angiography (OCT-A). We compared these changes with healthy controls to determine GAD’s impact on the retina. Methods An observational case-control study was conducted from January to May 2024 at the Benghazi Teaching Eye Hospital, including 40 GAD patients and 40 healthy controls aged 30–65 years. Participants underwent comprehensive ophthalmic assessments, including OCT and OCT-A. We analyzed retinal parameters such as central macular thickness (CMT), Macular volume, Ganglion cell layer thickness, and retinal nerve fiber layer (RNFL) thickness, along with vessel density in the macular and peripapillary regions. Results GAD patients exhibited significantly lower CMT (243.30±21.15 μm vs. 268.79±17.34 μm, P=0.001), Macular volume (9.48±0.62 mm3 vs. 10.17±0.39 mm3, P=0.001), Ganglion cell layer thickness (83.60±78.24 μm vs. 92.30±74.73 μm, P=0.001), and total RNFL thickness (93.90±11.05 μm vs. 97.76±8.67 μm, P=0.001) compared with controls. RNFL thinning was noted in the nasal, inferior, and temporal regions. However, OCT-A revealed no significant differences in vessel density in the peripapillary and central macular areas between GAD patients and controls. Conclusion Patients with GAD exhibit significant retinal structural changes, particularly in the macular and RNFL regions. However, no significant differences in retinal vessel density were observed. These findings suggest that GAD may impact retinal morphology but not vascular density, indicating potential biomarkers for early detection and monitoring of GAD-related neurodegeneration.

Assessment of RNFL and macular changes in the eye related to multiple substance use using OCT

Substance use is a chronic and recurrent public healthcare concern increasing in the world, causing negative outcomes. Two or more substance use is common among people who have substance use disorders and who receive treatment. For this reason, the present study aimed to measure Retinal Nerve Fiber Layer (RNFL), Mean Macular Thickness (MMT), Central Macular Thickness (CMT) in patients who have Multiple substance use disorder (MSUD) using Optical Coherence Tomography (OCT), considering that it will contribute to the literature. Among the inpatients who were rehabilitated in Elazig Mental Hospital Alcohol and Substance Addiction Treatment Center, 75 people who were diagnosed with MSUD according to DSM-5 and met the criteria, and 51 control groups were included in the study. RNFL, MMT and CMT measurements of both eyes of all participants were made by using the OCT. Total RNFL measurement were significantly thicker than the control group (p < 0.001). MMT and CMT of the eyes of the patient were thinner than the control group (p = 0.009, p < 0.001). The findings provide important contributions to the literature data and in light of these findings, it can be recommended to consider visual findings and possible neurodegeneration when evaluating patients in the addiction group and planning their treatment.

Rates of retinal nerve fiber layer loss in early-stage pseudoexfoliation and primary open-angle glaucoma patients using optical coherence tomography.

To characterize glaucoma progression in early-stage patients with retinal nerve fiber layer (RNFL) using the change analysis software (CAS), which was utilized to track RNFL thinning. We retrospectively analyzed 92 eyes of 92 patients with early-stage glaucoma. Patients were divided into two subgroups based on their diagnosis of pseudoexfoliation glaucoma (PEG) and primary open-angle glaucoma (POAG). A complete ophthalmologic examination was performed on all patients. Additionally, automated perimetry was conducted on each patient. Furthermore, Fourier-domain optical coherence tomography (OCT) was employed to measure RNFL and central corneal thickness. Using the OCT device's CAS, we computed the annual rate of total and glaucomatous RNFL thinning for each patient. A total of 44 PEG and 48 POAG patients were included in the study. The right eye measurements of these patients were analyzed and compared. The two groups were not significantly different in age, gender, and the number of visits per year (p > 0.05, for each). However, the difference between the mean RNFL thickness at baseline (91.39 ± 10.71 and 96.9 ± 8.6µm) and at the last visit (85.2 ± 15.76µm and 91.56 ± 9.58µm) was statistically significant between the two groups (p = 0.043, p = 0.039, respectively). Additionally, the difference in annual RNFL thinning rates (1.43 ± 0.81µm and 1.07 ± 0.32µm) between the two groups was statistically significant (p = 0.009). The annual rate of glaucomatous RNFL loss in early-stage PEG patients (1.23µm) was higher than in POAG patients (0.87µm). However, despite these loss rates, scotoma was not detected in the visual field tests of these patients. Therefore, using CAS in the follow-up of early-stage glaucoma patients is a useful alternative for monitoring glaucomatous progression. Furthermore, this method can be utilized in future research for the diagnosis and follow-up of glaucoma in special populations (e.g., those with pathological myopia or high hyperopia) that are not included in normative databases.

Risk factors of internal carotid artery stenosis in patients with proliferative diabetic retinopathy: an analysis using optical coherence tomography and optical coherence tomography angiography

BackgroundThis research investigates the correlation between the severity of internal carotid artery (ICA) stenosis and retinal parameters in patients with proliferative diabetic retinopathy (PDR), aiming to uncover potential risk factors.MethodsA retrospective analysis of 68 patients (136 eyes) diagnosed with bilateral PDR from January 1, 2017, to December 31, 2021, was conducted. Carotid artery stenosis (CAS) was assessed using neck computed tomography angiography (CTA) and carotid duplex ultrasound (CDUS), with stenosis classified into two groups: normal (group 1) and mild or above (group 2), based on the North American Symptomatic Carotid Endarterectomy Trial (NASCET) criteria. Optical coherence tomography (OCT) and OCT angiography (OCTA) measured several retinal parameters, including sub foveal choroidal thickness (SFCT), retinal nerve fiber layer (RNFL) thickness, ganglion cell-inner plexiform layer (GCIPL) thickness, vessel density (VD), and foveal avascular zone (FAZ) area. Statistical analyses determined correlations between ICA degrees and retinal parameters.ResultsThis study showed significant differences between groups in total VD, FAZ area, total RNFL thickness, and temporal RNFL thickness, indicating that patients with more severe ICA stenosis had noticeable retinal changes. Other parameters such as hyperlipidemia, total cholesterol levels, and intraocular pressure (IOP) also differed significantly, while no notable differences were observed in SFCT, central VD, average GCIPL, and superior, nasal, and inferior RNFL thickness.ConclusionThe study findings highlight retinal changes, such as an increased FAZ area, decreased total VD, and a total and thinner temporal RNFL, which suggest the need for carotid artery evaluation in patients. These findings have important clinical implications for the need for carotid work up in patients with PDR.

Attention flexibility is associated with retinal cup-to-disk ratio in patients with schizophrenia spectrum disorders

IntroductionIn recent years, there has been increasing interest in the potential use of retinal imaging as a non-invasive and easily accessible tool for investigating the neurobiological underpinnings of schizophrenia. Studies have suggested that patients with schizophrenia spectrum disorders (SSD) have structural abnormalities in the retina, including changes in retinal thickness and the ratio of the retinal cup-to-disk ratio.ObjectivesTo investigate the relationship between retinal cup-to-disk ratio and cognitive performance in patients with SSD using a high-definition retinal imaging device – optical coherence tomography (OCT) scanner.MethodsThe sample was comprised of twenty patients with SSD (F20-F29 according to ICD-10 criteria). All diagnoses were confirmed by a researcher using the Mini International Psychiatric Interview. All patients underwent complete ophthalmological examination, excluding any ocular pathology. Retinal thickness was measured in both eyes of all patients with a high-definition spectral-domain OCT device. Examined retinal parameters were: total retinal nerve fiber layer thickness (RNFL); RNFL thickness in all eye quadrants (nasal, temporal, superior, inferior); RNFL symmetry; average macular volume (MV); average macular thickness (MT); ganglion cell layer thickness (GC); average retinal cup-to-disk (C/D) ratio, vertical C/D ratio. Cognitive performance of all patients was tested using the Intra/Extradimensional Set Shift Task (IED). IED is a component of a state-of-the-art computerized battery for cognitive assessment – Cambridge Neuropsychological Automated Test Battery. IED is a measure of maintenance, shifting and flexibility of attention. Associations between retinal variables and IED measures were determined with Pearson correlation analyses.ResultsMean age of patients was 33 ± 7.5 years. Fifty five percent of the sample was male, illness duration was 6.2 ± 3.9 years. Daily dosage of chlorpromazine was 225.7 ± 108.8 mg. Retinal C/D ratio in the right eye was positively associated with IED total errors (r=0.50; p=0.02) and negatively with IED stage progression (r=-0.52, p=0.18). Likewise, vertical C/D ratio was positively associated with IED total errors (r=0.49; p=0.02) and negatively with IED stage progression (r=-0.52, p=0.18).ConclusionsPrevious analyses of retinal parameters in patients with schizophrenia point towards enlargement of retinal cup-to-disk ratio, irrespective of any underlying somatic comorbidities. Our data shows worsening of attention flexibility in association with the increase of cup-to-disk ratio in patients with schizophrenia spectrum disorders. The significance of cup-to-disk retinal disturbance in schizophrenia spectrum disorders and its connection with cognitive performance should be further evaluated and supplemented with measurements of functional adaptation in these patients.Disclosure of InterestNone Declared

Peripapillary retinal nerve fiber layer following vessel density correction at different IOP values.

The aim of this study was to define the thickness of the retinal nerve fiber layer (RNFL) in the peripapillary region of the retina after adjusting for the effect of vessel density (VD) in patients with pathological intraocular pressure (IOP). 69 patients (122 eyes) with IOP >21 mmHg (range 21-36 mmHg, mean 23.65±2.70 mmHg). 32 were men (average age 55±13 years) and 37 were women (average age 52±14 years). IOP was measured using the Ocular Response Analyser (ORA). VD and RNFL were measured peripapillary by OCT (Avanti RTVue XR) in eight segments: Inferior Temporal - IT (1); Temporal Inferior - TI (2); Temporal Superior -TS (3); Superior Temporal - ST (4); Superior Nasal - SN (5); Nasal Superior - NS (6); Nasal Inferior - NI (7) and Inferior Nasal - IN (8). The VD value was subtracted from the total RNFL value. A corrected value for the RNFLc nerve fiber layer thickness (RNFLc) was introduced to account for VD across the RNFL volume in each segment. Person's correlation coefficient (r) was used to assess the correlation between IOP and RNFLc. The strongest correlations in RNFLc were in segments 5 (r=-0.32, P=0.002) and 8 (r=-0.21, P=0.037). The greatest changes in RNFLc (RNFL minus VD) were in eyes with pathological IOP in segments 5 and 8, the location of the retinal ganglion cell magnocellular fibers. That is, when the thickness of the nerve fiber layer was reduced by correcting for vessel density, there was a significant correlation in segments 5 (r =-0.32, p<0.05) and 8 (r =-0.21, P<0.05) with intraocular pressure. The results suggest use of a corrected RNFL from VD value as more appropriate for detecting early changes in glaucoma.

Early detection of peripheral neuropathy in patients with diabetes mellitus type 2

BackgroundEarly diagnosis of diabetic polyneuropathy (DPN) can significantly improve the prognosis and help prevent severe complications. The aim of this work was to study clinical, radiological, laboratory and neurophysiological findings for early detection of peripheral neuropathy in T2DM.MethodsA total of 60 diabetic patients were classified according to Toronto Clinical Neuropathy Score (TCNS) into: Group 1: 20 diabetic patients with no evident neuropathy. Group 2: 20 diabetic patients with mild neuropathy. Group 3: 20 diabetic patients with moderate and severe neuropathy. All patients underwent a neurological examination, nerve conduction studies and optical coherence tomography (OCT) to assess retinal nerve fiber layer (RNFL) thickness. Additionally, ELISA technique to measure serum interleukin-6 (IL-6).ResultsThe analysis of gender and age distributions among the groups revealed no significant differences. There were statistically significant differences regarding disease duration, HBA1c, body mass index Systolic and diastolic blood pressure. Group 3 had such significant impairment that resulted in an inability to record the measurements of sural nerves. The study's statistical analysis results for OCT variables, and post hoc comparisons revealed significant differences between all three groups. The results demonstrated significant variations in Serum IL6 levels among the groups, with Group 3 having the highest IL6 levels. In groups 1, 2, and 3 the area under the curve for IL-6 and RNFL showed a good differentiation ability between groups.ConclusionWe conclude that the total thickness RNFL and serum IL-6 levels are a potential biomarker in prediction the severity of DPN.

Early effects of cardiopulmonary bypass surgery on retinal nerve fiber layer and ganglion cell layer

PurposeTo determine the effects of cardiopulmonary bypass surgery on retinal nerve fiber layer, ganglion cell layer, and macula by optic coherens tomography (OCT). MethodSixty-six eyes of 33 patients aged between 44 and 74 who were indicated for cardiopulmonary bypass surgery in the cardiovascular surgery clinic were included in the study. Routine ophthalmologic examinations of all patients were performed before and 1 week after surgery. In addition, 3D(H) Macula+5 Line Cross 12 × 9 mm mod and Peripapilar 3D Disk 6 × 6 mm mod data were analyzed with OCT (Topcon, Triton Swept Source-OKT, Tokyo, Japan) device. Peripapillary total, superior, inferior retinal nerve fiber layer (RNFL), optic disc cavity volume, cup-to-disc ratio, macular ganglion cell layer (GCL), macular thickness were compared before and after surgery. ResultsAfter cardiopulmonary bypass surgery, thickening was detected in the total RNFL (p<0.001), superior RNFL (p = 0.01) and inferior RNFL (p<0.001) layers. There was no change in the values of GCL, macular thickness, optic disc cupping volume, cup-to-disc ratio after surgery (p>0.05).There was a positive correlation (r = 0.392 p<0.05) between the patients' blood oxygen (PO2) values during bypass surgery with their post-surgical GCL+ values, and a negative correlation between optic disc cup volumes (r=-0.349 p<0.05). ConclusionRNFL thickening has been detected in patients undergoing cardiopulmonary bypass surgery. This thickening may occur secondary to ischemic edema that occurs during surgery. Considering the late complications of ischemic edema in the RNFL, oxygen levels should be kept at an optimum level during surgery and long-term ophthalmologic follow-ups should be performed.

OPTIC DISK PIT STUFFING-TO DO OR NOT TO DO.

Optic disk pit (ODP) is a subset of spectrum of congenital cavitary anomalies. Optic disk pit maculopathy causes progressive visual deterioration and is addressed with pars plana vitrectomy (PPV) with or without ODP stuffing. We report a case of progressive ODP maculopathy who was taken up for 23-G 3-port PPV, with complete vitreous removal and stuffing of the ODP with autologous sclera and sequential analysis of change in the retinal nerve fiber layer (RNFL) thickness. Spectral-domain optical coherence tomography RNFL analysis at 1 and 12 months follow-up postoperatively showed total RNFL thickness decrease from 130 µm to 103 µm respectively. Hemiquadrant analysis showed slight reduction of superior RNFL thickness from 142 µm to 139 µm. However, in the inferior hemiquadrant, the reduction in mean RNFL thickness seems to be significant from 133 µm to 100 µm at 1 and 12 months respectively. Sector-wise analysis of the RNFL thickness showed maximum reduction in the inferotemporal quadrant and other sectors seemed to be relatively preserved corresponding to the area of scleral stuffing. Retrospective or prospective analysis of RNFL health of patients undergoing surgery for ODP-M with stuffing needs to evaluated.

The Effect of Myopia on Vessel Density in Glaucomatous Patients by Optical Coherence Tomography Angiography.

Glaucoma is a degenerative optic neuropathy that causes anatomical and functional visual impairment. This investigation's primary goal was to perform a qualitative and quantitative assessment of macular and peripapillary vessels to detect the impairment of blood flow in glaucomatous patients with or without myopia which can affect the prognosis of glaucoma and visual field. This prospective, cross-sectional, observational research was performed for glaucomatous patients with and without myopia who attend the outpatient clinic at the ophthalmology department, at Benha University. The study was conducted on 50 subjects with glaucomatous eyes, divided into two groups: the first group consisted of (25 subjects) of glaucoma with myopia and the second group (25 subjects) of glaucoma with the same severity of mean deviation in the visual field of group 1 without myopia, using OCTA to measure retinal vessel density (superficial vessel density) and OCT thickness ILM-RPE, RNFL thickness, GCL and small vessel density (RADIAL PERI PAPILLARY PLEXUS). Regarding demographic data of myopia in the studied eyes, there were (9) 18% with low myopia with no significance, (32) 64% with moderate myopia, and (9) 18% with high myopia, with open-angle glaucoma patients showed a highly significant decline in total retinal nerve fiber layer thickness, superior-nasal RNFL thickness, Inferior-nasal RNFL thickness, superior-temporal RNFL and inferior-temporal RNFL thickness compared to open-angle glaucoma patients without myopia. Our results show that microvascular attenuation occurs more significantly in OAG than in myopia. When both myopia and OAG are present, there is a higher reduction in microvascular attenuation than with either disease alone. The development and progression of glaucoma in individuals with high myopia are more aggressive than in low or non-myopia, so by using OCTA detection of early microvascular changes in high myopia, individuals help the early detection and management of glaucoma.

Optic Nerve Head Parameters in Saudi Male Young Adults Using Swept-source Optical Coherence Tomography.

To assess the optic nerve head (ONH) parameters in normal male Saudi eyes using swept-source optical coherence tomography (SS-OCT). The study included 86 healthy men with a mean age of 23.6 ± 4.82 years. The metrics collected using SS-OCT from each individual was disk area (DA), rim area (RA), cup volume (CV), linear cup-disk ratio (LCDR), vertical cup-disk ratio (VCDR), and total retinal nerve fiber layer (RNFL) thickness, superior RNFL thickness, and inferior RNFL thickness. All the metrics were correlated with the DA. The right eye data were used for the correlation analysis. The mean DA in OD was 1.78 mm2 (range 1.09-2.70 mm2). The mean RA was 1.28 mm2 (range 0.72-2.47 mm2). The DA showed a significant positive correlation (p < 0.05) with RA, cup area (CA), CV, VCDR, LCDR, and total RNFL thickness. For the first time, using sweeping source OCT (DRI OCT Triton, Topcon Corporation), a normative database of ONH parameters was made accessible to the Saudi male population. While assessing the optic disk for progressive optic neuropathies like glaucoma, disk size should be taken into consideration since the optic DA affects ONH topography, especially in Saudi eyes. Challa NK. Optic Nerve Head Parameters in Saudi Male Young Adults Using Swept-source Optical Coherence Tomography. J Curr Glaucoma Pract 2023;17(2):58-62.

Retinal nerve fiber layer and ophthalmic artery blood flow parameters in pseudoexfoliation syndrome and pseudoexfoliative glaucoma

To investigate the relationship between ophthalmic artery (OA) blood flow parameters and retinal nerve fiber layer (RNFL) thickness in eyes with pseudoexfoliation (PEX). We compared PEX eyes without glaucoma (group A, n=53) and those with glaucoma (group B, n=18) with control eyes (group C, n=44). Subsequently, eyes in groups A and B were compared. Finally, OA color Doppler imaging measurements were recorded, and peripapillary RNFL analysis was performed. The total RNFL measurements differed significantly among the groups (P=0.012), being thicker in group C than in group A (P=0.010) and significantly different between group B and groups A and C (both P=0.001). The peak systolic velocity (PSV) and end diastolic velocity (EDV) measurements of groups A and B were lower than those of group C (PSV: P=0.001 and P=0.001, respectively; EDV: P=0.001 and P=0.001, respectively). No significant difference was noted in resistive index (RI) measurements (P=0.370). In group B, significant negative correlations were noted between total RNFL and PSV (r=-0.743; P=0.001) and between total RNFL and EDV (r=-0.691; P=0.001), but not between total RNFL and RI measurements (P=0.548). Pseudoexfoliation syndrome (PXS) with or without glaucoma was associated with a decrease in the PSV and EDV values of the OA. An extensive study may be needed to further explore the role of PXS in OA blood flow parameters. Total RNFL thickness values were lower in eyes with PEX than in those without.

Effect of nutritional-deficiency anemia on peripapillary retinal nerve fiber layer: A North Indian study.

The purpose of this study was to evaluate the effect of nutritional-deficiency anemia (NDA) on peripapillary retinal nerve fiber layer thickness (PPRNFLT) using spectral-domain optical coherence tomography and to determine any correlation arising thereof. This was a single-center, cross-sectional, observational study. A total 115 eyes of 115 NDA patients (50 of each with iron-deficiency anemia [IDA] and Vitamin B12-deficiency anemia [BDA], and 15 with folic acid-deficiency anemia [FDA]) aged 18-65 years were compared with a total 100 eyes of 50 age- and sex-matched healthy controls. All subjects underwent comprehensive clinical, ophthalmic, and hematological evaluation, followed by PPRNFLT assessment for the mean total, superior, inferior, nasal, and temporal quadrants. PPRNFLT for the mean total and all four quadrants in IDA patients, for the mean total, inferior, nasal, and temporal quadrants in BDA patients, and for the mean total, inferior, and nasal quadrants, in FDA patients, was significantly lower as compared to the controls (P < 0.05). The mean total PPRNFLT of all NDA patients correlated significantly (P < 0.05) with their relevant hematological parameters with Pearson's coefficient (r) value of 0.613, 0.610, 0.336, 0.295, 0.337, 0.374, and - 0.509, respectively, for serum haemoglobin (Hb), iron, ferritin, mean corpuscular volume (MCV), mean cell hemoglobin, mean corpuscular hemoglobin concentration, and total iron binding capacity in IDA; 0.310, 0.435, and - 0.386, respectively, for serum Hb%, Vitamin B12, and MCV in BDA; and 0.557, 0.358, and - 0.294 for Hb%, folate, and MCV, respectively, in FDA cases. Mean total retinal nerve fiber layer thinning of all NDA patients showed progression with the increasing severity grades of anemia, except in very severe BDA where an inverse relationship was documented. Our study revealed that PPRNFLT is significantly thinner in all NDA patients (total and all four quadrants in IDA; total, inferior, nasal, and temporal in BDA; and total, inferior, and nasal in FDA) correlating well with their relevant hematological parameters. Early detection of this may be crucial in preventing potential blinding sequelae and differentiating glaucomatous and other neuro-ophthalmic disorders.

Influence of Patient Age and Presence of Optic Disc Drusen on Fluctuations in Retinal Nerve Fiber Layer Thickness.

It is generally believed that optic disc drusen (ODD) change only over long periods of time. Because, in our experience, this does not apply to younger patients, we investigated the natural course of changes of the peripapillary retinal nerve fiber layer (RNFL) in patients with ODD. In this retrospective study, 40 eyes with and 40 eyes without ODD were examined, both cohorts were equally subdivided into younger subjects (20 years or younger) and older subjects (21 years or older). Three optical coherence tomography (OCT) scans of the peripapillary RNFL that had an interval of at least 1 month were required for each patient to be included in this study. The largest difference in total RNFL thickness (delta RNFL-t) and in RNFL thickness of the most differing sector (delta RNFL max) measured by OCT was compared. The differences in total RNFL thickness and in the most differing RNFL sector in the group of patients with ODD younger than 21 years were significantly larger than in each of the other 3 groups ( P = 0.0001). The other 3 groups did not differ significantly. Patients with ODD younger than 21 years have distinct variations in peripapillary RNFL thickness without evidence of increased intracranial pressure. In the absence of further pathological findings or neurological symptoms, an observational approach seems adequate in these patients.

Individual and Combined Effects of Diabetes and Glaucoma on Total Macular Thickness and Ganglion Cell Complex Thickness: A Cross-sectional Analysis.

Presence of diabetes in glaucoma patients may influence findings while documenting the progression of glaucoma. We conducted the study to compare individual and combined effects of diabetes and glaucoma on macular thickness and ganglion cell complex thickness. The present study is a cross-sectional analysis of 172 eyes of 114 individuals. The groups were categorized according to the following conditions: glaucoma, diabetes mellitus, both glaucoma and diabetes (`both' group), and none of these conditions (`none' group). Patients with diabetes did not have diabetic retinopathy (DR). We compared retinal nerve fiber layer (RNFL) thickness, ganglion cell complex (GCC) thickness, foveal loss of volume (FLV), and global loss of volume (GLV) among the groups. We used random effects multivariate analysis to adjust for potential confounders. The mean (SD) age of these individuals was 60.7 (10.1) years. The total average RNFL and GCC were significantly lower in the glaucoma group (RNFL: -36.27, 95% confidence intervals [CI]: -42.79 to -29.74; P 0.05, and GCC: -26.24, 95% CI: -31.49 to -20.98; P 0.05) and the `both' group (RNFL: -24.74, 95% CI: -32.84 to -16.63; P 0.05, and GCC: -17.92, 95% CI: -24.58 to -11.26; P 0.05) as compared with the `none' group. There were no significant differences in the average RNFL values and total average GCC between the diabetes group and the `none' group. The values of FLV and GLV were significantly higher in the `glaucoma' group and the `both' group as compared with the `none' group. The foveal values were not significantly different across these four groups. Among the glaucoma cases, 25% were mild, 30% were moderate, and 45% were severe; there was no significant difference in the proportion of severity of glaucoma between the `glaucoma only' and `both' groups (p=0.32). After adjusting for severity and type of glaucoma, there were no statistically significant differences in the values of average RNFL (6.6, 95% CI: -1.9 to 15.2; P=0.13), total average GCC (3.6, -95% CI: -2.4 to 9.6; P=0.24), and GLV (-3.9, 95% CI: -9.5 to 1.6; P=0.16) in the `both group' as compared with the glaucoma only group. We found that diabetes with no DR did not significantly affect the retinal parameters in patients with glaucoma. Thus, it is less likely that thickness of these parameters will be overestimated in patients with glaucoma who have concurrent diabetes without retinopathy.

Morphological and Functional Assessment of the Optic Nerve Head and Retinal Ganglion Cells in Dry vs Chronically Treated Wet Age-Related Macular Degeneration

PurposeThe aim of the study comprised the anatomical and functional assessment of the optic nerves and macular ganglion cells in the population of patients with unilateral wet age-related macular degeneration (wAMD) and comparison of its results to those obtained from the fellow eye with non-advanced dry age-related macular degeneration (dAMD). Furthermore, we aimed to determine if the number of administered injections contributed to the potential differences between the examined eyes.MethodsThe study was based on 104 eyes of 52 patients in a cross-sectional study. The eyes with chronically treated wAMD were the main subject of the study, while fellow eyes affected with non-advanced dAMD served as the control group. Primary morphological outcomes comprised differences in peripapillary retinal nerve fiber layer (RNFL) and GCC layers between the studied groups (treated and control). In turn, primary functional outcomes included differences in implicit times and amplitudes of the P100 wave of pattern visual evoked potentials (PVEP) and N95 wave of pattern electroretinogram (PERG) between treated and control groups.ResultsWe did not find any differences in total RNFL thickness between wAMD and dAMD groups. The number of injections only affected the RNFL in the nasal quadrant of the optic disc (p = 0.023). We did not find any differences regarding GCL thickness in both groups. In the study group, a longer implicit time of the P100 of PVEP (p = 0.014) and a shorter amplitude of the P50-N95 wave of PERG (p = 0.005) were detected. The total number of injections had no significant effect on these two values.ConclusionWe detected worse functional parameters of the optic nerve and retinal ganglion cells in eyes with wAMD, with lack of significant differences in anatomical (RNFL, GCL) parameters compared to the control group. However, the number of injections did not contribute to the differences found.

Comparison of the Structure-Function Relationship Between Advanced Primary Open Angle Glaucoma and Normal Tension Glaucoma.

The aim was to investigate and compare the characteristics of visual field (VF) defects in primary open angle glaucoma (POAG) and normal-tension glaucoma (NTG) with advanced glaucomatous damage and to determine whether the structure-function relationships found in advanced glaucoma differ based on their glaucoma classification. Ninety-seven eyes of 97 patients (59 eyes with POAG and 38 eyes with NTG) with advanced glaucoma were included in this cross-sectional study. Scores at each test point of the 30-2 VF total deviation map were recorded, and average values at each test point were point-wise compared between the groups. Peripapillary retinal nerve fiber layer (RNFL) and macular thickness (total, RNFL, ganglion cell layer, and inner plexiform layer thickness) were measured. The structure-function relationship based on the map of Garway-Heath was determined and compared between the 2 groups. At advanced stage of glaucoma, POAG eyes demonstrated more diffusely distributed VF defects, whereas NTG eyes had more severe VF defects at the superior nasal quadrant, showing increased asymmetry. Overall, peripapillary RNFL, macular ganglion cell layer, and macular inner plexiform layer thickness showed good relationships with 30-2 VF parameters in both groups. However, in total macula and macular RNFL thickness, the structure-function relationships tended to show different characteristics depending on the glaucoma classification; NTG eyes showed overall better relationships. In advanced glaucoma, differences in patterns of VF damage were found between POAG and NTG eyes. Conventional peripapillary RNFL and macular measurements showed generally good performance for estimating functional status, particularly in NTG eyes.

Associated Factors and Distribution of Peripapillary Retinal Nerve Fiber Layer Thickness in Children by Optical Coherence Tomography: A Population-based Study

To determine the distribution of peripapillary retinal nerve fiber layer (RNFL) thickness and its association with different demographic and ocular parameters in adolescents. The present study is part of the second phase of the Shahroud Schoolchildren Eye cohort study, which was conducted in 2018 by reinviting the participants in the first phase. First, preliminary ocular examinations were performed, including measurement of uncorrected and best-corrected visual acuity, autorefraction, and subjective refraction.All study participants underwent corneal imaging using Pentacam to measure central corneal thickness and corneal radius of curvature (keratometry), ocular biometry using Allegro Biograph to measure anterior chamber depth, crystalline lens thickness, and axial length (AL), and finally optical coherence tomography imaging to measure RNFL thickness as well as macular thickness and volume. The data of 4963 right eyes were analyzed after applying the exclusion criteria. The mean age of the study participants was 12.41±1.72 (9 to 15) years. The mean total, superior, inferior, temporal, and nasal RNFL thicknesses were 98.93 [95% confidence interval (CI): 98.61-99.25], 122.84 (95% CI: 122.31-123.37), 129.17 (95% CI: 128.63-129.7), 68.02 (95% CI: 67.65-68.38), and 75.69 (95% CI: 75.3-76.07), respectively. According to the results of the multivariable regression model, macular volume (β=9.81, P =0.001) had a significant direct association, and macular thickness (β=-0.01, P =0.046) had a significant inverse association with the average RNFL thickness. In addition, AL (β=-3.14, P <0.001), mean keratometry (β=-1.38, P <0.001), and central corneal thickness (β=-0.01, P =0.011) were significantly inversely related to the average RNFL thickness. We report the distribution of peripapillary RNFL thickness using spectral-domain optical coherence tomography and identify macular volume, AL, and mean keratometry as significantly associated factors in children. Our findings may serve as a database to interpret RNFL thickness results in children aged 9 to 15 years with suspected ocular disease.

Relationships Among Retinal Nerve Fiber Layer Thickness, Vascular Endothelial Growth Factor, and Cognitive Impairment in Patients with Schizophrenia.

BackgroundStudies have suggested retinal nerve fiber layer (RNFL) involvement in the pathogenesis of schizophrenia. Additionally, research has shown that vascular endothelial growth factor (VEGF) potentially contributes to the pathophysiology of psychiatric disorders. Therefore, this study aimed to investigate VEGF, RNFL, and correlations with cognitive impairments in schizophrenia patients.MethodsPatients with schizophrenia (n = 138) were compared to healthy controls (n = 160). RNFLs were measured with optical coherence tomography (OCT). The Stroop color and word test (SCWT) was used to evaluate neurocognition. Blood samples were collected to measure VEGF. SPSS 20.0 was used to perform analysis of covariance, t-tests, partial correlation analysis, and linear regression.ResultsThinner RNFLs were found in schizophrenia patients (p < 0.001). RNFL showed a significant correlation with SCWT scores (all p < 0.05). Serum level of VEGF was lower in patients with schizophrenia (p = 0.010). Total and inferior RNFL thicknesses of right eyes were positively correlated to VEGF level (RNFL total thickness p = 0.032, inferior thickness p = 0.014).Total RNFL thicknesses were shown to be reduced following a prolonged duration of illness (both p < 0.01).ConclusionThese findings suggest that patients with schizophrenia have degeneration with RNFL thickness following illness duration, which may contribute to neurocognitive impairments observed in schizophrenia. VEGF is speculated to play some important role on RNFL degeneration with schizophrenia patients.

Phase 1b Randomized Controlled Study of Short Course Topical Recombinant Human Nerve Growth Factor (rhNGF) for Neuroenhancement in Glaucoma: Safety, Tolerability, and Efficacy Measure Outcomes

No approved therapies directly target retinal ganglion cells (RGCs) for neuroprotection or neuroenhancement in glaucoma. Recombinant human nerve growth factor (rhNGF) has been shown to promote RGC survival and function in animal models of optic neuropathy. Here we evaluate the safety, tolerability, and efficacy of short-term, high-dose rhNGF eye drops versus placebo in a cohort of glaucoma patients. This was a prospective, phase 1b, single-center, randomized, double-masked, vehicle-controlled, parallel-group study. This study was designed to assess safety and tolerability as well as short-term neuroenhancement of structure and function (clinicaltrials.gov NCT02855450). A total of 60 open-angle glaucoma patients were randomized 40:20 to receive either 180 μg/mL rhNGF or vehicle control eye drops in both eyes, 3 times daily for 8 weeks, with a 24-week post-treatment follow-up. One eye was officially selected as the study eye, although both eyes were studied and dosed. Primary endpoints were safety, as assessed by adverse events, and tolerability, as assessed by patient-reported outcomes. Secondary outcome measures included best corrected visual acuity (BCVA), Humphrey visual field, electroretinograpy (ERG), and optical coherence tomography (OCT) of retinal nerve fiber layer (RNFL) thickness at baseline, after 8 weeks of treatment, and at 4 and 24 weeks after treatment (12 and 32 weeks total). Of the 60 randomized patients, 23 were female (38%) and the average age was 66.1 years. Through week 32, there were no treatment-related serious adverse events, including no unexpectedly severe progression of optic neuropathy, no adverse events affecting ocular function or pressure, and no drug-related systemic toxicity. Topical high-dose rhNGF was tolerated well, with a low level of symptom burden mainly eliciting periocular ache (in 52% of treated group and 5% of placebo group) and only 3 patients (7.5%) discontinuing treatment because of discomfort, of whom 1 patient (2.5%) prematurely withdrew from the study. There were no statistically significant differences in global indices of Humphrey visual field and no meaningful differences in total, quadrant, or clock-hour mean RNFL thickness between the groups, although both of these function and structure measures showed nonsignificant trends toward significance in favor of rhNGF. Real-world participant data was used to generate an estimate of cohort size needed to power subsequent studies. Use of rhNGF is safe and tolerable in a topical 180-μg/mL formulation. Although no statistically significant short-term neuroenhancement was detected in this trial, given the strong effects of NGF in preclinical models and the trends detected in this study, analysis for efficacy in a neuroprotection trial is warranted. NOTE: Publication of this article is sponsored by the American Ophthalmological Society.