Retinal Nerve Fiber Layer Thickness Research Articles

Evaluation of Visual Cortex Activity using Functional Near-Infrared Spectroscopy (fNIRS) in Primary Open Angle and Primary Angle Closure Glaucoma: A pilot study.

Functional Near Infrared Spectroscopy was used to assess visual cortical activity in patients with primary open angle and primary angle closure glaucoma. There was decreased activity in the visual cortex of glaucoma patients correlating with the severity of glaucoma. To evaluate visual cortex activity using fNIRS (Functional Near Infrared Spectroscopy) in primary open angle glaucoma (POAG) and primary angle closure glaucoma (PACG) compared to healthy controls. A total of 30 POAG, 31 PACG, and 30 healthy aged-matched controls from a single centre were recruited in this cross-sectional observational pilot study with purposive sampling. The POAG and PACG groups were age-matched but were not matched for disease severity at recruitment. All participants underwent fNIRS testing using a multi-channel continuous-wave near infra-red system NIRSport 8×7 device (NIRx Medizintechnik GmbH, Berlin, Germany). The visual cortex activity was evaluated in terms of maximum amplitude of change in oxyhemoglobin (OxyHb) concentration over 10 seconds and a comparison was done between three groups. Both POAG and PACG groups were combined (termed as glaucoma group) to assess relationship of visual cortical activity with disease severity {by visual field defect (mean deviation) and retinal nerve fiber layer (RNFL) thickness}. All participants showed the characteristic response of increased OxyHb and decreased DeoxyHb during stimulus presentation. The maximum amplitude of change in OxyHb concentration over 10 seconds was significantly lower in both POAG and PACG groups compared to control in the right and left middle occipital gyri (P<0.05). There was no significant difference between PACG and POAG. Importantly, there was a negative correlation of the visual cortex activity with the visual field defects (mean deviation) (P<0.05) and a positive correlation with RNFL thickness in the glaucoma group (P<0.05). In glaucoma patients, reduction in visual cortical activity was observed which may be indicative of neuronal degeneration occurring in the occipital cortex. Disease severity in glaucoma appears to be closely correlated with visual cortex activity. fNIRS can serve as a useful neuroimaging modality for assessing the hemodynamic and neurodegenerative changes in glaucoma.

Clinical features of patients with mutations in genes for nanophthalmos

Background/AimsTo distinguish the clinical feature of nanophthalmos (NNO) caused by mutations in protease serine 56 (PRSS56), membrane-type frizzled-related protein (MFRP), myelin regulatory factor (MYRF) and transmembrane protein 98 (TMEM98) and...

Enhancing the structure–function relationship in glaucoma using anatomical compensation of retinal nerve fibre layer

Background/aimsTo investigate whether compensating retinal nerve fibre layer (RNFL) thickness measurements for demographic and anatomical ocular factors can strengthen the structure–function relationship in patients with glaucoma.Methods600 eyes from 412 patients...

Clinical characteristics of viral-associated Fuchs uveitis syndrome and Posner-Schlossman syndrome in a Chinese population.

To identify the types of viral infection in aqueous humor (AqH) among patients diagnosed as Fuchs uveitis syndrome (FUS) or Posner-Schlossman syndrome (PSS) and investigate their relevance to clinical manifestations and visual outcome. A total of 375 patients and 171 patients were diagnosed as FUS or PSS in our department. AqH and serum samples from 68 FUS patients and 16 PSS patients were obtained during eye surgery. The viral etiologies, clinical features, auxiliary tests and visual prognosis of patients with FUS or PSS who underwent AqH analysis were analysed and compared. Among 68 FUS patients, rubella virus (RV), cytomegalovirus (CMV), herpes simplex virus (HSV) and varicella-zoster virus were identified in 17, 11, 1 and 1 patients, respectively. Seven patients with CMV and 1 with HSV were identified in 16 PSS patients. In both FUS and PSS groups, virus-associated eyes had higher proportion of secondary glaucoma and worse visual prognosis as compared with non-virus-associated eyes (all P < 0.05). In FUS group, specifically, CMV infection manifested as more obvious anterior segment inflammation and lower corneal endothelial cell density (CECD). RV infection showed a higher percentage of vitritis. In PSS group, CMV-associated PSS had a lower retinal nerve fiber layer thickness and CECD, worse visual prognosis as compared with non-virus-associated PSS (all P < 0.05). Our study identified 4 types of viral infection in FUS and 2 types of viral infection in PSS. Virus-associated patients are usually associated with more obvious clinical signs and poor visual prognosis.

Does collagen cross linking have any effect on retinal circulation in patients with keratoconus? An optical coherence tomography angiography (OCTA) study

BackgroundWe aimed to employ Optical Coherence Tomography Angiography (OCTA) to comprehensively assess changes in the optic nerve head (ONH) and macular perfusion before and after the Corneal Collagen Cross-Linking (CCL) procedure in patients with keratoconus.MethodsA total of 22 keratoconus patient’s candidate for CCL procedures were included based on specific criteria, with meticulous exclusion criteria in place to minimize potential confounders. Participants underwent OCTA assessments of the ONH and macula using the Spectralis OCT (Heidelberg) before CCL, as well as at 1- and 3-months post-CCL. MATLAB software was utilized for image analysis.ResultsThe mean age of the participants was 20.09 ± 6.11, including 59% male, and the mean intraocular pressure (IOP) before the surgery was 13.59 ± 2.85 mmHg. Peripapillary Retinal nerve fiber layer (ppRNFL) thickness and overall retinal thickness remained stable post-CCL. However, significant alterations were observed in macular vessel density, emphasizing regional variations in vascular response. For macular large vessel density (LVD), both superficial and deep vascular complex (SVC and DVC) demonstrated significant differences between before surgery and the 3 months post-surgery follow-up (p < 0.001 and p = 0.002, respectively). Optic nerve head markers demonstrated relative stability, except for changes in avascular complex density, which was 49.2 ± 2.2% before the surgery and decrease to 47.6 ± 1.7% three months after the operation (P-value = 0.005).ConclusionWhile CCL appears to maintain the integrity of certain ocular structures, alterations in macular perfusion post-CCL suggest potential effects on retinal blood supply. Long-term monitoring is crucial to understand the implications of these changes, particularly in the context of conditions such as diabetes.

Biological and Methodological Variability in Retinal Nerve Fiber Layer OCT: The Framingham Heart Study

Biological and Methodological Variability in Retinal Nerve Fiber Layer OCT: The Framingham Heart Study

Retinal Nerve Fiber Layer Damage Assessment in Glaucomatous Eyes Using Retinal Retardance Measured by Polarization-Sensitive Optical Coherence Tomography.

To assess the diagnostic performance and structure-function association of retinal retardance (RR), a customized metric measured by a prototype polarization-sensitive optical coherence tomography (PS-OCT), across various stages of glaucoma. This cross-sectional pilot study analyzed 170eyes from 49 healthy individuals and 68 patients with glaucoma. The patients underwent PS-OCT imaging and conventional spectral-domain optical coherence tomography (SD-OCT), as well as visual field (VF) tests. Parameters including RR and retinal nerve fiber layer thickness (RNFLT) were extracted from identical circumpapillary regions of the fundus. Glaucomatous eyes were categorized into early, moderate, or severe stages based on VF mean deviation (MD). The diagnostic performance of RR and RNFLT in discriminating glaucoma from controls was assessed using receiver operating characteristic (ROC) curves. Correlations among VF-MD, RR, and RNFLT were evaluated and compared within different groups of disease severity. The diagnostic performance of both RR and RNFLT was comparable for glaucoma detection (RR AUC = 0.98, RNFLT AUC = 0.97; P = 0.553). RR showed better structure-function association with VF-MD than RNFLT (RR VF-MD = 0.68, RNFLT VF-MD = 0.58; z = 1.99; P = 0.047) in glaucoma cases, especially in severe glaucoma, where the correlation between VF-MD and RR (r = 0.73) was significantly stronger than with RNFLT (r = 0.43, z = 1.96, P = 0.050). In eyes with early and moderate glaucoma, the structure-function association was similar when using RNFLT and RR. RR and RNFLT have similar performance in glaucoma diagnosis. However, in patients with glaucoma especially severe glaucoma, RR showed a stronger correlation with VF test results. Further research is needed to validate RR as an indicator for severe glaucoma evaluation and to explore the benefits of using PS-OCT in clinical practice. We demonstrated that PS-OCT has the potential to evaluate the status of RNFL structural damage in eyes with severe glaucoma, which is currently challenging in clinics.

Quantifying Putative Retinal Gliosis in Preclinical Alzheimer's Disease.

Neuroinflammation plays a significant role in the pathology of Alzheimer's disease (AD). Mouse models of AD and postmortem biopsy of patients with AD reveal retinal glial activation comparable to central nervous system immunoreactivity. We hypothesized that the surface area of putative retinal gliosis observed in vivo using en face optical coherence tomography (OCT) imaging will be larger in patients with preclinical AD versus controls. The Spectralis II instrument was used to acquire macular centered 20 × 20 and 30 × 25-degrees spectral domain OCT images of 76 participants (132 eyes). A cohort of 22 patients with preclinical AD (40 eyes, mean age = 69 years, range = 60-80 years) and 20 control participants (32 eyes, mean age = 66 years, range = 58-82 years, P = 0.11) were included for the assessment of difference in surface area of putative retinal gliosis and retinal nerve fiber layer (RNFL) thickness. The surface area of putative retinal gliosis and RNFL thickness for the nine sectors of the Early Treatment Diabetic Retinopathy Study (ETDRS) map were compared between groups using generalized linear mixed models. The surface area of putative retinal gliosis was significantly greater in the preclinical AD group (0.97 ± 0.55 mm2) compared to controls (0.68 ± 0.40 mm2); F(1,70) = 4.41, P = 0.039; Cohen's d = 0.61. There was no significant difference between groups for RNFL thickness in the 9 ETDRS sectors, P > 0.05. Our analysis shows greater putative retinal gliosis in preclinical AD compared to controls. This demonstrates putative retinal gliosis as a potential biomarker for AD-related neuroinflammation.

Fundus Tessellation and Parapapillary Atrophy, as Ocular Characteristics of Spontaneously High Myopia in Macaques: The Non-Human Primates Eye Study.

This study aimed to evaluate the ocular characteristics associated with spontaneously high myopia in adult nonhuman primates (NHPs). A total of 537 eyes of 277 macaques with an average age of 18.53 ± 3.01 years (range = 5-26 years), raised in a controlled environment, were included. We measured ocular parameters, including spherical equivalent (SE), axial length (AXL), and intraocular pressure. The 45-degree fundus images centered on the macula and the disc assessed the fundus tessellation and parapapillary atrophy (PPA). Additionally, optical coherence tomography (OCT) was used to measure the thickness of the retinal nerve fiber layer (RNFL). The mean SE was -1.58 ± 3.71 diopters (D). The mean AXL was 18.76 ± 0.86 mm. The prevalence rate of high myopia was 17.7%. As myopia aggravated, the AXL increased (r = -0.498, P < 0.001). Compared with non-high myopia, highly myopic eyes had a greater AXL (P < 0.001), less RNFL thickness (P = 0.004), a higher incidence of PPA (P < 0.001), and elevated grades of fundus tessellation (P < 0.001). The binary logistic regression was performed, which showed PPA (odds ratio [OR] = 4.924, 95% confidence interval [CI] = 2.375-10.207, P < 0.001) and higher grades of fundus tessellation (OR = 1.865, 95% CI = 1.474-2.361, P < 0.001) were independent risk characteristics for high myopia. In NHPs, a higher grade of fundus tessellation and PPA were significant biomarkers of high myopia. The study demonstrates adult NHPs raised in conditioned rooms have a similar prevalence and highly consistent fundus changes with human beings, which strengthens the foundation for utilizing macaques as an animal model in high myopic studies.

Observation on the changes of visual field and optic nerve fiber layer thickness in patients with early diabetic retinopathy

BackgroundDiabetic retinopathy (DR) is a common complication of diabetes mellitus (DM) and is a leading cause of vision loss. Early detection of DR-related neurodegenerative changes is crucial for effective management and prevention of vision loss in diabetic patients. MethodsIn this study, we employed spectral-domain polarization-sensitive optical coherence tomography (SD PS-OCT) to assess retinal nerve fiber layer (RNFL) changes in 120 eyes from 60 types 1 DM patients without clinical DR and 60 age-matched healthy controls. Visual field testing was performed to evaluate mean sensitivity (MS) and mean defect (MD) as indicators of visual function. ResultsSD PS-OCT measurements revealed significant reductions in RNFL birefringence, retardation, and thickness in type 1 DM patients compared to healthy controls. Visual field testing showed decreased MS and increased MD in DM patients, indicating functional impairment correlated with RNFL alterations. ConclusionOur findings demonstrate early neurodegenerative changes in the RNFL of type 1 DM patients without clinical DR, highlighting the potential of SD PS-OCT as a sensitive tool for early detection of subclinical DR-related neurodegeneration. These results underscore the importance of regular ophthalmic screenings in diabetic patients to enable timely intervention and prevent vision-threatening complications.

Progression or Aging? A Deep Learning Approach for Distinguishing Glaucoma Progression from Age-Related Changes in OCT scans

To develop deep learning (DL) algorithm to detect glaucoma progression using optical coherence tomography (OCT) images, in the absence of a reference standard. Retrospective cohort study. Glaucomatous and healthy eyes with ≥5 reliable peripapillary OCT (Spectralis, Heidelberg Engineering) circle scans were included. A weakly supervised time-series learning model, called Noise Positive-Unlabeled (Noise-PU) DL was developed to classify whether sequences of OCT B-scans showed glaucoma progression. The model used two learning schemes, one to identify age-related changes by differentiating test sequences from glaucoma vs. healthy eyes, and the other to identify test-retest variability based on scrambled OCTs of glaucoma eyes. Both models' bases were convolutional neural networks (CNN) and long short-term memory (LSTM) networks which were combined to form a CNN-LSTM model. Model features were combined and jointly trained to identify glaucoma progression, accounting for age-related loss. The DL model's outcomes were compared with ordinary least squares (OLS) regression of retinal nerve fiber layer (RNFL) thickness over time, matched for specificity. The hit ratio was used as a proxy for sensitivity. 8,785 follow-up sequences of 5 consecutive OCT tests from 3253 eyes (1859 subjects) were included in the study. Mean follow-up time was 3.5±1.6 years. In the test sample, the hit ratios of the DL and OLS methods were 0.498 (95%CI:0.470-0.526) and 0.284 (95%CI:0.258-0.309) respectively (P<0.001) when the specificities were equalized to 95%. A DL model was able to identify longitudinal glaucomatous structural changes in OCT B-scans using a surrogate reference standard for progression.

Clinical efficacy of dexamethasone parabulbar injection in patients with Nonarteritic anterior ischemic optic neuropathy

BackgroundNonarteritic anterior ischemic optic neuropathy (NAAION) is a common optic neuropathy that often leads to significant visual acuity loss in patients. The present study evaluated the effects of parabulbar dexamethasone injection on visual outcomes in patients with NAAION. MethodsThis retrospective case-control study included patients diagnosed with NAAION between January 2019 and December 2022. Thirty-four patients with NAAION (34 eyes) received dexamethasone parabulbar injections, while 39 patients with NAAION (39 eyes) received oral corticosteroid treatment (control group). Best-corrected visual acuity (BCVA), visual field (VF) defect, and retinal nerve fiber layer (RNFL) thickness of the affected eye were compared between groups at baseline and 2, 6, and 12 weeks post-treatment. ResultsMean BCVA significantly improved after 6 and 12 weeks in the injection groups compared with the control group (all P < 0.01). The visual field indices, mean deviation and pattern standard deviation significantly improved in the injection group compared with the control group after 2, 6, and 12 weeks (all P < 0.01). The RNFL showed a remarkable decrease in edema after 6 weeks (superior and nasal P values 0.005 and 0.013, respectively) in the injection group compared with the control group. Significant RNFL thinning was also observed in superior, inferior, temporal, and nasal quadrants in the control group after 12 weeks (all P values < 0.01). Also, fewer side effects were observed in the injection group compared to the control group. ConclusionsThe results of this study suggested that dexamethasone parabulbar injection might be a safe and effective intervention for relieving visual acuity and VF in patients with NAAION.

The Association of Urinary Sodium Excretion with Glaucoma and Related Traits in a Large United Kingdom Population

Excessive dietary sodium intake has known adverse effects on intravascular fluid volume and systemic blood pressure, which may influence intraocular pressure (IOP) and glaucoma risk. This study aimed to assess the association of urinary sodium excretion, a biomarker of dietary intake, with glaucoma and related traits, and to determine whether this relationship is modified by genetic susceptibility to disease. Cross-sectional observational and gene-environment interaction analyses in the population-based UK Biobank study. Up to 103 634 individuals (mean age 57 years, 51% women) with complete urinary, ocular, and covariable data. Urine sodium:creatinine ratio (UNa:Cr; mmol:mmol) was calculated from a midstream urine sample. Ocular parameters were measured as part of a comprehensive eye examination and glaucoma case ascertainment was through a combination of self-report and linked national hospital records. Genetic susceptibility to glaucoma was calculated based on a glaucoma polygenic risk score (PRS) comprising 2 673 common genetic variants. Multivariable linear and logistic regression, adjusted for key sociodemographic, medical, anthropometric, and lifestyle factors, were used to model associations and gene-environment interactions. Corneal-compensated IOP, optical coherence tomography derived macular retinal nerve fiber layer (mRNFL) and ganglion cell-inner plexiform layer (GCIPL) thickness, and prevalent glaucoma. In maximally adjusted regression models, a one standard deviation increase in UNa:Cr was associated with higher IOP (0.14mmHg; 95% CI, 0.12 to 0.17; P<0.001) and greater prevalence of glaucoma (OR, 1.11; 95% CI, 1.07 to 1.14; P<0.001), but not mRNFL or GCIPL thickness. Compared to those with UNa:Cr in the lowest quintile, those in the highest quintile had significantly higher IOP (0.45mmHg; 95% CI, 0.36 to 0.53, P<0.001) and prevalence of glaucoma (OR, 1.30; 95% CI, 1.17 to 1.45; P<0.001). Stronger associations with glaucoma (P interaction=0.001) were noted in participants with a higher glaucoma PRS. Urinary sodium excretion, a biomarker of dietary intake, may represent an important modifiable risk factor for glaucoma, especially in individuals at high underlying genetic risk. These findings warrant further investigation as they may have important clinical and public health implications.

Rapid Retinal Nerve Fiber Layer Thinning in the Unaffected Contralateral Eyes of Patients with Unilateral Normal-Tension Glaucoma: A retrospective observational study

PurposeTo observe the rate of progressive retinal nerve fiber layer (RNFL) thinning in the unaffected eyes of patients with unilateral normal-tension glaucoma (NTG), in comparison with that of healthy subjects, and to identify the factors associated with progressive RNFL thinning. DesignRetrospective, longitudinal, observational study. ParticipantsNinety-five patients with unilateral NTG and 61 healthy controls MethodsThis study included unilateral NTG and healthy control subjects who were followed up for longer than 4 years and in whom at least 5 reliable RNFL thickness (RNFLT) measurements were performed using optical coherence tomography. Factors associated with the rate of thinning of the unaffected eyes of unilateral NTG patients were identified using regression analysis. Main Outcome MeasuresThe rate of progressive RNFL thinning and the associated factors. ResultsRNFLT decreased significantly in both the unaffected eyes of unilateral NTG patients and the healthy eyes (both P<0.001). The RNFL thinning was significantly faster in the unaffected eyes of unilateral NTG patients than in the healthy eyes (P<0.001), specifically in the temporal-inferior sector (P=0.003). Factors associated with faster RNFL thinning in the unaffected eyes of unilateral NTG patients were thicker baseline RNFL of the unaffected eyes (P=0.002) and a worse visual field (VF) mean deviation (MD) in the NTG eyes (P=0.040). In the healthy controls, the rate of RNFL thinning in the contralateral eyes was the only factor associated with faster thinning (P=0.007). ConclusionsThe unaffected eyes of unilateral NTG patients showed faster RNFL thinning than healthy control eyes, more obviously in the temporal-inferior sector, and were likely to progress faster when they had a thicker baseline RNFL, and when the NTG eyes had a worse VF MD. In unilateral NTG patients, initiation of prophylactic treatment could be considered for the unaffected eyes when they are accompanied by a risk of developing glaucoma.

OPTICAL COHERENCE TOMOGRAPHY ANALYSIS OF RETINAL THICKNESS IN COVID-19 PATIENTS

OBJECTIVE: The aim of this study was to perform Optical Coherence Tomography analysis of retinal changes in patients with COVID-19 infection and compare them with healthy controls. MATERIAL AND METHODS: For this purpose, 42 COVID-19 positive patients (group 1) and 44 healthy adults (group 2), aged between 18 and 68 years, who were admitted to our clinic between October 1, 2020 and May 1, 2021, were included in the study. Central foveal thickness, choroidal thickness (subfoveal) and peripapillary retinal nerve fiber thickness were measured. Measurements were performed at the central fovea and at 1500 μm nasal and 1500 μm temporal points from the central fovea. RESULTS: Age and gender distribution were similar in the groups (p=0.610 and p=0.992, respectively). However, central foveal thickness (p&amp;lt;0.001), subfoveal choroidal thickness (p=0.001) and peripapillary retinal nerve fiber layer thickness (p&amp;lt;0.001) were significantly different between the two groups. CONCLUSIONS: In conclusion, central fovea, subfoveal choroidal and peripapillary retinal nerve fiber layer thickness were higher in polymerase chain reaction positive COVID-19 patients compared to healthy controls. To understand the pathogenesis of systemic and local changes caused by COVID-19, multicenter and long-term studies with a large number of patient subgroups are necessary.

Longitudinal change of retinal layer thickness in cognitively normal elderly subjects: population-based cohort study

Purpose: To identify longitudinal retinal layer thickness changes in normal eyes of cognitively healthy older participants. Methods: Post-hoc analysis was performed on 57 cognitively healthy older participants from the population-based KLoSHA and KLOSCAD cohort studies who underwent baseline and final optical coherence tomography (OCT) scans. The peripapillary retinal nerve fiber layer, subfoveal choroid, and average retinal layer thickness at four quadrant (nasal, temporal, superior, and inferior) points 1 mm, 2 mm, and 3 mm from the center of the fovea were measured. Results: Among the analyzed retinal layers, both the ganglion cell-inner plexiform layer (GCIPL) and the outer nuclear layer (ONL) at all 1, 2, and 3 mm points showed a statistically significant decrease in thickness at the final visit compared to baseline. The annual decrease rates were -1.2 μm/year at 1 mm (total -6.6%), -1.3 μm/year at 2 mm (total -8.4%), -1.1 μm/year at 3 mm (total -9.7%) for GCIPL; -0.6 μm/year at 1 mm (total -4.2%), -0.5 μm/year at 2 mm (total -3.9%), and -0.4 μm/year at 3 mm (total -4.1%) for ONL. Conclusions: Age plays a significant role in the reduction of GCIPL and ONL thicknesses in cognitively healthy elderly individuals.

Refining Glaucoma Diagnosis and Treatment in Cataract Surgery Candidates: The Contribution of Preoperative OCT RNFL.

To evaluate the clinical significance of preoperative spectral domain optical coherence tomography (OCT) of the retinal nerve fiber layer (RNFL) thickness in identifying glaucoma and better managing patients scheduled for routine cataract surgery. Department of Ophthalmology, Shaare Zedek Medical Center, Jerusalem, Israel.Design: retrospective cohort study. Consecutive patients scheduled for cataract surgery were enrolled from February 2022 to August 2022. Participants underwent routine OCT RNFL studies which were evaluated by a glaucoma specialist. Findings were compared with those of preoperative fundus biomicroscopic examinations conducted by the referring ophthalmologist. The main outcomes were the incidence of newly detected glaucoma based upon OCT RNFL findings and the consequent changes in patient management. In total, 486 patients met the inclusion criteria, of whom 112 (23%) had abnormal RNFL. Thirty-one patients (6.4%) had abnormal OCT RNFL findings attributed to comorbidities other than glaucoma, and 81 patients (16.7%) were suspected to have glaucoma based upon their OCT RNFL findings, from which 44 patients (9%) were newly diagnosed with glaucoma or as glaucoma suspects, resulting in management modifications that included routine glaucoma follow-up (25 patients, 5.1%), initiation of intraocular pressure-lowering treatment (12 patients, 2.5%), and conversion to combined cataract-glaucoma surgery (7 patients, 1.4%). OCT RNFL for cataract surgery candidates proved valuable in detecting glaucoma that had not been revealed by standard fundus biomicroscopic examination. The additional information provided by OCT RNFL can potentially enhance patient management and optimize outcomes.

Effect of intravitreal injections due to neovascular age-related macular degeneration on retinal nerve fiber layer thickness and minimum rim width: a cross sectional study

PurposeThe present study tested the hypothesis that repeated anti-VEGF injections are associated with reduced retinal nerve fiber layer (RNFL) and minimum rim width (MRW) of the optic nerve head.Patients and methodsSixty-six patients with a history of intravitreal injections due to neovascular age-related macular degeneration were included. RNFL and MRW were measured using optical coherence tomography (Spectralis OCT, Heidelberg Engineering, Heidelberg, Germany).ResultsMean global RNFL was 90.62 μm and both RNFL as well as MRW significantly decreased with advanced age (p = 0.005 and p = 0.019, respectively). Correlating for the number of injections, no significant impact on RNFL was found globally (p = 0.642) or in any of the sectors. In contrast, however, global MRW was significantly reduced with increasing numbers of intravitreal injections (p = 0.012). The same holds true when adjusted for the confounding factor age (RNFL p = 0.566 and MRW p = 0.023).ConclusionOur study shows that repeated intravitreal injections due to choroidal neovascularization seem to have a deleterious effect on MRW but not on RNFL. This suggests that MRW is a more sensitive marker than RNFL for evaluating the effect of frequent intravitreal injections on the optic nerve head since it seems to be the first structure affected.

Myopia and Rate of Peripapillary Retinal Nerve Fiber Layer Thickness in Diabetic Patients Without Retinopathy: A 2-Year Longitudinal Study

Purpose The aim of this study was to investigate the association between myopia and longitudinal changes in peripapillary retinal nerve fiber layer (pRNFL) thickness in type 2 diabetic patients without diabetic retinopathy (DR). Methods A total of 1069 participants with a median follow-up time of 1.9 years were included in this study. The participants were categorized into four groups based on the presence of myopia (≤ –0.5 diopter [D]) and diabetes without DR, including a control group (n = 412), diabetes group (n = 416), myopia group (n = 115), and diabetes + myopia group (n = 126). Peripapillary average and sectoral RNFL measurements were obtained using 6 × 6 mm swept-source optical coherence tomography (SS-OCT) scans centered at the optic disc. The change rate of pRNFL, adjusted for age and sex, was calculated and compared among the four groups to investigate the impact of myopia and diabetes. Results The baseline estimated pRNFL thickness after adjustment for covariates was 113.7 μm, 116.2 μm, 108.0 μm, and 105.6 μm in the control, diabetes, myopia, and diabetes + myopia group, respectively (diabetes > control > myopia = diabetes + myopia, p < 0.001). The respective average pRNFL loss in the four groups was –0.48 μm/year, –1.11 μm/year, –1.23 μm/year, and -2.62 μm/year (all p < 0.01). The diabetes + myopia group exhibited a greater rate of average pRNFL reduction compared to the other groups (all p < 0.001). Multivariate analysis using a linear mixed-effects model showed that age, diabetes, axial length (AL), and baseline pRNFL thickness were significantly associated with the rate of average pRNFL reduction. Conclusions The diabetes group showed a faster rate of average pRNFL thickness reduction compared to healthy controls, regardless of the presence of myopia. The average pRNFL thickness decreased more rapidly when diabetes and myopia were present simultaneously than in the individual diabetes or myopia group. Both diabetes and myopia were associated with accelerated pRNFL loss.

Optic chiasm involvement in multiple sclerosis, aquaporin-4 antibody-positive neuromyelitis optica spectrum disorder and myelin oligodendrocyte glycoprotein–associated disease

Background: Optic neuritis (ON) is a common feature of inflammatory demyelinating diseases (IDDs) such as multiple sclerosis (MS), aquaporin 4-antibody neuromyelitis optica spectrum disorder (AQP4 + NMOSD) and myelin oligodendrocyte glycoprotein antibody–associated disease (MOGAD). However, the involvement of the optic chiasm (OC) in IDD has not been fully investigated. Aims: To examine OC differences in non-acute IDD patients with (ON+) and without ON (ON−) using magnetisation transfer ratio (MTR), to compare differences between MS, AQP4 + NMOSD and MOGAD and understand their associations with other neuro-ophthalmological markers. Methods: Twenty-eight relapsing-remitting multiple sclerosis (RRMS), 24 AQP4 + NMOSD, 28 MOGAD patients and 32 healthy controls (HCs) underwent clinical evaluation, MRI and optical coherence tomography (OCT) scan. Multivariable linear regression models were applied. Results: ON + IDD patients showed lower OC MTR than HCs (28.87 ± 4.58 vs 31.65 ± 4.93; p = 0.004). When compared with HCs, lower OC MTR was found in ON + AQP4 + NMOSD (28.55 ± 4.18 vs 31.65 ± 4.93; p = 0.020) and MOGAD (28.73 ± 4.99 vs 31.65 ± 4.93; p = 0.007) and in ON− AQP4 + NMOSD (28.37 ± 7.27 vs 31.65 ± 4.93; p = 0.035). ON+ RRMS had lower MTR than ON− RRMS (28.87 ± 4.58 vs 30.99 ± 4.76; p = 0.038). Lower OC MTR was associated with higher number of ON (regression coefficient (RC) = −1.15, 95% confidence interval (CI) = −1.819 to −0.490, p = 0.001), worse visual acuity (RC = −0.026, 95% CI = −0.041 to −0.011, p = 0.001) and lower peripapillary retinal nerve fibre layer (pRNFL) thickness (RC = 1.129, 95% CI = 0.199 to 2.059, p = 0.018) when considering the whole IDD group. Conclusion: OC microstructural damage indicates prior ON in IDD and is linked to reduced vision and thinner pRNFL.