Ganglion Cell-inner Plexiform Layer Thickness Research Articles

Evaluation of retinal microcirculation alterations using OCTA in hyperopic ametropic amblyopia patients before and after treatment

PurposeWe aimed to compare retinal microcirculation in hyperopic ametropic amblyopia patients before and after treatment and in healthy children using optical coherence tomography angiography (OCTA), and to explore the pathogenesis of hyperopic ametropic amblyopia.MethodsEighteen patients with hyperopic ametropic amblyopia aged 4–8 years were selected as the patient group, and 18 age-matched healthy children were randomly selected as controls. The foveal avascular zone (FAZ) area, perimeter and circularity, vessel density (VD) and perfusion density (PD) of macular superficial retinal capillary plexus, macular thickness, peripapillary retinal nerve fiber layer thickness, and ganglion cell-inner plexiform layer thickness were compared between both groups. After 6 months of amblyopia treatment, the same parameters were measured again.ResultsThe VD and PD in the central, inner, inner nasal, and inner inferior regions in hyperopic ametropic amblyopia were lower than in the control group after adjustment for axial length. After 6 months of treatment, the VD increased significantly, except in the outer nasal and outer inferior regions. The PD in the central (p < 0.001), inner superior (p = 0.001), inner inferior (p = 0.011) and inner temporal (p = 0.026) regions increased. The FAZ perimeter and circularity significantly differed between the groups. After 6 months of treatment, the FAZ area and perimeter decreased, but circularity increased.ConclusionHyperopic ametropic amblyopia eyes showed a significant decrease in vessel and perfusion densities. After amblyopia treatment, the vessel and perfusion densities of patients with hyperopic ametropic amblyopia increased, suggesting that abnormalities in the microvascular system are a pathogenic factor of amblyopia.

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.

Intraocular Pressure and Rates of Macular Thinning in Glaucoma

To evaluate the effect of intraocular pressure (IOP) on the rates of macular thickness (ganglion cell layer [GCL] and ganglion cell-inner plexiform layer [GCIPL]) change over time measured by spectral-domain (SD) OCT. Retrospective cohort study. Overall, 451 eyes of 256 patients with primary open-angle glaucoma. Data were extracted from the Duke Ophthalmic Registry, a database of electronic medical records of patients observed under routine clinical care at the Duke Eye Center, and satellite clinics. All records from patients with a minimum of 6 months of follow-up and at least 2 good-quality Spectralis SD-OCT macula scans were included. Linear mixed models were used to investigate the relationship between average IOP during follow-up and rates of GCL and GCIPL thickness change over time. The effect of IOP on the rates of GCL and GCIPL thickness loss measured by SD-OCT. Eyes had a mean follow-up of 1.8 ± 1.3 years, ranging from 0.5 to 10.2 years. The average rate of change for GCL thickness was-0.220 μm/year (95% confidence interval [CI],-0.268 to-0.172 μm/year) and for GCIPL thickness was-0.231 μm/year (95% CI,-0.302 to-0.160 μm/year). Each 1-mmHg higher mean IOP during follow-up was associated with an additional loss of-0.021 μm/year of GCL thickness (P= 0.001) and-0.032 μm/year of GCIPL thickness (P= 0.001) after adjusting for potentially confounding factors, such as baseline age, disease severity, sex, race, central corneal thickness, and follow-up time. Higher IOP was significantly associated with faster rates of GCL and GCIPL loss over time measured by SD-OCT, even during relatively short follow-up times. These findings support the use of SD-OCT GCL and GCIPL thickness measurements as structural biomarkers for the evaluation of the efficacy of IOP-lowering therapies in slowing down the progression of glaucoma. Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

The Effects of Long-term Growth Hormone Treatment on Ocular Findings.

This study aimed to examine the long-term changes in anterior chamber depth (ACD), central corneal thickness (CCT), axial length (AxL), peripapillary retinal nerve fibre layer thickness (RNFLT), peripapillary ganglion cell layer - inner plexiform layer (GCL-IPL) thickness, and peripapillary choroidal thickness (ChT) after rhGH replacement treatment in paediatric patients with IGHD, compared to healthy controls. Twenty-two children with IGHD including 12 girls and 10 boys were enrolled in the study group, and 30 (16 girls, 14 boys) healthy children composed the control group. A detailed ophthalmological examination was performed for each participant. ACD, CCT, AxL, peripapillary RNFLT, GCL-IPL thickness and ChT measurements were performed before the rhGH replacement treatment and in the 12th month of the post-treatment period, as well as the corresponding visits in the control group. AxL ultrasound pachymetry (CCT), peripapillary RNFL thickness, peripapillary RNFLT, GCL-IPL thickness, and peripapillary ChT parameters were measured by spectral-domain optical coherence tomography. The mean age of the groups were similar (p = 0.143). 12-month CCT, ACD, and AxL measurements of the study group showed significantly higher results than the pre-treatment measurements (p = 0.005, p = 0.024, and p = 0.002, respectively). Similarly, the mean RNFLT and ChT measurements of the study group obtained from all sectors were significantly higher in the 12th-month visit (p < 0.001 for both) other than the RNFLT, and GCL-IPL thickness measurements (p > 0.05 for all). However, all these parameters were similar at pre- and post-treatment visits in the control group (p > 0.05 for all). The mean pre-treatment values of all these parameters were significantly lower in the study group compared to the control group (p < 0.05 for all), other than the RNFLT, GCL-IPL thickness measurements (p > 0.05 for all), while the mean post-treatment values of all these parameters in both groups were similar at month 12 (p > 0.05 for all). GH replacement treatment in childhood may play an important role in the development of the neural retina and can be effective on the anterior segment, RNFLT and ChT measurements.

Swept-Source Optical Coherence Tomography Thresholds in Differentiating Clinical Outcomes in a Real-World Cohort of Treatment-Naïve Multiple Sclerosis Patients

This study aimed to determine whether peripapillary retinal nerve fiber layer (pRNFL) and ganglion cell-inner plexiform layer (GCIPL) thickness thresholds for single-time-point swept-source optical coherence tomography (SS-OCT) measures can differentiate the clinical outcomes of treatment-naïve people with multiple sclerosis (pwMS). A total of 275 patients with the clinically isolated syndrome (n = 23), benign MS (n = 8), relapsing-remitting MS (n = 185), secondary progressive MS (n = 28), primary progressive MS (n = 31), and with no history of optic neuritis were included. The mean Expanded Disability Status Scale (EDSS) score was 3.0 ± 1.6. The cut-off values of pRNFL (87 µm and 88 µm) and GCIPL (70 µm) thicknesses have been adopted from previous studies using spectral-domain OCT. PwMS with pRNFL ≤87 µm and ≤88 µm had a longer disease duration, more advanced disability, and more frequently progressive MS variants compared to those with greater pRNFL thicknesses. In distinguishing pwMS with disability greater than or equal to the mean EDSS score (EDSS ≥ 3) from those with less severe disability, GCIPL thickness <70 µm had the highest sensitivity, while pRNFL thickness ≤87 µm had the greatest specificity. The optimal cut-off values differentiating patients with EDSS ≥ 3 from those with less severe disability was 63 µm for GCIPL thickness and 93.5 µm for pRNFL thickness. In conclusion, pRNFL and GCIPL thickness thresholds for single-time-point SS-OCT measurements may be helpful in differentiating the disability status of treatment-naïve pwMS.

Diagnostic accuracy of retinal optical coherence tomography in children with a newly diagnosed brain tumour.

To estimate the diagnostic accuracy of circumpapillary retinal nerve fibre layer (RNFL) thickness and macular ganglion cell layer-inner plexiform layer (GCL-IPL) thickness measurements to discriminate an abnormal visual function (i.e. abnormal age-based visual acuity and/or visual field defect) in children with a newly diagnosed brain tumour. This cross-sectional analysis of a prospective longitudinal nationwide cohort study was conducted at four hospitals in the Netherlands, including the national referral centre for paediatric oncology. Patients aged 0-18 years with a newly diagnosed brain tumour and reliable visual acuity and/or visual field examination and optical coherence tomography were included. Diagnostic accuracy was evaluated with sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV). Of 115 patients included in the study (67 [58.3%] male; median age 10.6 years [range, 0.2-17.8 years]), reliable RNFL thickness and GCL-IPL thickness measurements were available in 92 patients (80.0%) and 84 patients (73.0%), respectively. The sensitivity for detecting an abnormal visual function was 74.5% for average RNFL thickness and 41.7% for average GCL-IPL thickness at a specificity of 44.5% and 82.9%, respectively. The PPV and NPV were 33.0% and 82.6% for the average RNFL thickness and 57.1% and 82.2% for the average GCL-IPL thickness. An abnormal visual function was discriminated correctly by using the average RNFL thickness in seven out of ten patients and by using the average GCL-IPL thickness in four out of ten patients. The relatively high NPVs signified that patients with normal average RNFL thickness and average GCL-IPL thickness measurements had a relative high certainty of a normal visual function.

Evaluation of retinal microcirculation alterations using optical coherence tomography angiography in patients with hyperopia ametropic amblyopia: A case-control study.

Given that there are controversial findings regarding vessel density in amblyopia, we quantified retinal microcirculation using optical coherence tomography angiography and compared it between hyperopic ametropic amblyopia eyes and age-matched control eyes. This case-control study was conducted from March 2021 to March 2022 at the Affiliated Eye Hospital of Nanchang University, Nanchang, China. Both groups included 72 eyes. Foveal avascular zone area, circularity and perimeter, perfusion density and vessel density of macular superficial retinal capillary plexus, macular thickness, macular volume, peripapillary retinal nerve fiber layer thickness, and ganglion cell-inner plexiform layer thickness were compared between hyperopia ametropic amblyopia eyes and age-matched control eyes. Additionally, best-corrected visual acuity, maximum corneal curvature, minimum corneal curvature, and anterior chamber depth were measured. In the hyperopia ametropic amblyopia eyes and control eyes, vessel density was 7.51 ± 2.13 and 9.91 ± 2.71 mm-1 in the central, 17.20 ± 1.38 and 18.25 ± 1.37 mm-1 in the inner, and 17.90 ± 0.88 and 18.43 ± 0.97 mm-1 in the full regions, respectively. The perfusion densities were 0.17 ± 0.06 and 0.23 ± 0.07 in the central, 0.41 ± 0.05 and 0.44 ± 0.03 in the inner, and 0.44 ± 0.03 and 0.46 ± 0.02 in the full regions, respectively. The central macular thicknesses of hyperopia ametropic amblyopia and control eyes were 240.04 ± 20.11 and 235.08 ± 24.41 µm, respectively. Foveal avascular zone perimeter and circularity (P < .043 and P = .001) significantly differed between the 2 groups. Hyperopia ametropic amblyopia eyes showed lower appreciably in vessel and perfusion densities, which could be one of the major pathophysiological mechanisms of hyperopia ametropic amblyopia and provide a new direction for the diagnosis and treatment of amblyopia.

Changes in Retinal Thickness and Brain Volume during 6.8-Year Escalating Therapy for Multiple Sclerosis

Background. Different disease-modifying therapies (DMT) for multiple sclerosis (MS) have disparate effects on disability outcomes. Sweden has a leading position globally in initiating high-efficacy DMT instead of escalating DMT from 1st-line to high-efficacy DMT. With optical coherence tomography (OCT), retinal changes can be measured at a few micrometer level. OCT has been increasingly applied in diagnosing MS and monitoring disease course and therapeutic effect. Objective. We investigate the effects of 1st-line versus high-efficacy DMT for MS on retinal and brain atrophy and on functional outcomes during 6.8 years of escalating DMT. Materials and Methods. In this prospective longitudinal observational study, 18 MS patients were followed up for 6.8 years. Twelve of the patients were untreated at baseline. All patients underwent 1st-line DMT for median duration of 2.4 years and then switched to high-efficacy DMT for a median duration of 2.9 years. Findings from neurological examinations, MRI, and OCT measures were registered 2-4 times per year. Results. Ganglion cell-inner plexiform layer (GCIPL) thickness was significantly reduced during 1st-line DMT (73.75 μm, p &lt; 0.01 ) compared to baseline (76.38 μm). During high-efficacy DMT, thickness reduction was slower (73.27 μm, p &lt; 0.05 ), and MRI contrast-loading lesions vanished ( p &lt; 0.01 ). However, brain parenchymal fraction (BPF) decreased during high-efficacy DMT compared to 1st-line DMT. Estimated models showed similar results. Conclusion. GCIPL decline was most profound during 1st-line DMT and diminished during high-efficacy DMT. MRI contrast lesions vanished during high-efficacy DMT. However, brain atrophy continued regardless of high-efficacy DMT.

In vivo evaluation of macular microvasculature in childhood malnutrition using optical coherence tomography angiography.

To evaluate the microvascular alterations and foveal avascular zone (FAZ) changes in the foveal and parafoveal region in malnourished children. This cross-sectional study analyzed 168 eyes of 85 patients. The subjects were split into 3 groups based on their body mass index (BMI) percentiles and defined as Group 1 (BMI percentiles ≥95th, overnutrition group), Group 2 (BMI <5th percentile, undernutrition group) and Group 3 (BMI ≥5th and <85th percentile, control group). All subjects were examined with optical coherence tomography angiography (OCTA) to evaluate superficial capillary plexus (SCP), deep capillary plexus (DCP) vessel density (VD) and FAZ parameters. The retinal nerve fiber layer (RNFL), average macular ganglion cell-inner plexiform layer (GCL-IPL), inner limiting membrane-retinal pigment epithelium(ILM-RPE) thickness were evaluated using SD-OCT device. Age and gender did not statistically differ across groups (p=0.12 and p=0.92). Groups 1 and 2 were found to have significantly higher VD of the superior-hemisphere of the DCP levels than the control group (p=0.001). The control group's foveal VD of SCP was statistically higher than group 1's (p=0.012). Parafoveal VD was significantly increased in the superior of the SCP of group 1 and the lower hemisphere of the SCP of group 2 compared with the control group (p=0.02 and p=0.02, respectively). The mean FAZ perimeter, choriocapillaris flow area, RNFL, GCL-IPL and ILM-RPE thickness were similar between all groups. The childhood undernutrition and overnutrition may affect the density of retinal capillaries. Although the FAZ area and choriocapillary flow did not change, retinal capillary density tended to increase in malnutrition.

Associations Between Thinner Retinal Neuronal Layers and Suboptimal Brain Structural Integrity in a Middle-Aged Cohort.

The retina has potential as a biomarker of brain health and Alzheimer's disease (AD) because it is the only part of the central nervous system which can be easily imaged and has advantages over brain imaging technologies. Few studies have compared retinal and brain measurements in a middle-aged sample. The objective of our study was to investigate whether retinal neuronal measurements were associated with structural brain measurements in a middle-aged population-based cohort. Participants were members of the Dunedin Multidisciplinary Health and Development Study (n=1037; a longitudinal cohort followed from birth and at ages 3, 5, 7, 9, 11, 13, 15, 18, 21, 26, 32, 38, and most recently at age 45, when 94% of the living Study members participated). Retinal nerve fibre layer (RNFL) and ganglion cell-inner plexiform layer (GC-IPL) thickness were measured by optical coherence tomography (OCT). Brain age gap estimate (brainAGE), cortical surface area, cortical thickness, subcortical grey matter volumes, white matter hyperintensities, were measured by magnetic resonance imaging (MRI). Participants with both MRI and OCT data were included in the analysis (RNFL n=828, female n=413 [49.9%], male n=415 [50.1%]; GC-IPL n=825, female n=413 [50.1%], male n=412 [49.9%]). Thinner retinal neuronal layers were associated with older brain age, smaller cortical surface area, thinner average cortex, smaller subcortical grey matter volumes, and increased volume of white matter hyperintensities. These findings provide evidence that the retinal neuronal layers reflect differences in midlife structural brain integrity consistent with increased risk for later AD, supporting the proposition that the retina may be an early biomarker of brain health.

Childhood Social Isolation as a Predictor of Retinal Neuronal Thickness in Middle Age: A Lifecourse Birth Cohort Study.

We investigated whether childhood social isolation was associated with retinal neural layer changes in adulthood, and whether this association was independent of other childhood or adulthood risk factors, including adult social isolation. Participants were members of the Dunedin Multidisciplinary Health and Development Study, a longitudinal population-based birth cohort from Aotearoa New Zealand ( n = 1037), born 1972 to 1973 and followed until age 45 years, with 94% of the living cohort still participating. Social isolation was recorded prospectively at ages 5, 7, 9, and 11 years, from teacher and parent report. Retinal nerve fiber layer (RNFL) and ganglion cell-inner plexiform layer thicknesses were measured via optical coherence tomography at age 45 years. Childhood social isolation was associated with thinner average RNFL ( B = -0.739, p = .02), nasal RNFL ( B = -1.118, p = .005), and inferior RNFL ( B = -1.524, p = .007), although only nasal RNFL remained significant after adjustment. These associations were not fully explained by other psychosocial or physical health risk factors in childhood or adulthood, nor were they mediated by adult loneliness or social support. Childhood social isolation was an independent predictor of RNFL thickness in middle age. Highlighting prospective links between childhood psychosocial adversity and retinal neuronal measures will help to inform future research into the utility of retinal neuronal thickness as a biomarker for neurodegeneration.

Structural and vascular changes in glaucoma with single-hemifield defect: predictors of opposite hemifield visual field progression.

To investigate longitudinal changes in optic nerve head (ONH) superficial vessel density (VD), macular VD, circumpapillary retinal nerve fiber layer (RNFL) thickness, and macular ganglion cell-inner plexiform layer (GCIPL) thickness, and their associations with future VF defects in unaffected hemifields of primary open angle glaucoma (POAG) eyes with baseline VF defect confined to a single hemifield. This retrospective observational study included 61 POAG eyes with VF defect confined to a single hemifield monitored over a mean follow-up time of 2.7years. Development of VF defect in opposite hemifield was defined based the Early Manifest Glaucoma Trail criteria. Each eye was classified into either "conversion" or "no conversion" groups according to development of VF defect in the unaffected hemifield. The rates of longitudinal changes in VD and structure parameters in each hemiretina were compared between the two groups. A Cox proportional hazard model was used to identify potential risk factors for VF conversion in the unaffected hemifield. Among 61 eyes, 17 eyes (27.9%) were classified as "conversion" and 44 eyes (72.1%) were classified as "non-conversion" groups. The conversion group exhibited significantly greater rates of both VD and structural changes in both hemiretinas. In Cox proportional hazard model, greater rate of change in GCIPL thickness, ONH superficial VD, and macular VD of both hemiretinas and greater rate of change in RNFL thickness of the unaffected hemiretina were identified as risk factors for VF conversion in the unaffected hemifield. Monitoring progressive changes in VD and structural parameters effectively predict future VF defect in the opposite hemifields of POAG eyes with single-hemifield defects.

A prospective study of disease modifying therapy and retinal atrophy in relapsing-remitting multiple sclerosis

BackgroundTo compare the rate of retinal atrophy over time in patients with relapsing-remitting multiple sclerosis (RRMS) treated with various disease-modifying therapies (DMT). MethodsPatients with RRMS on various DMT and those observed without treatment were prospectively enrolled into the study between September 2015 and June 2018. All subjects with follow-up of 1–4 years were included and categorized into groups as “no drug”, “low efficacy drug”, “high efficacy drug”, or “dimethyl fumarate” (DMF), based on treatment modality used for the longest duration of their follow-up. Ocular coherence tomography (OCT) was used to measure peripapillary retinal nerve fiber layer thickness (RNFL) and ganglion cell/inner plexiform layer (GC-IPL) thickness at baseline and every 6 months. A linear mixed effects regression model was performed to compare rates of retinal atrophy across treatment groups. ResultsOut of 67 participants who met inclusion criteria (mean age = 37; 76% female), 13 were untreated, 12 on low efficacy therapy, 18 on DMF, and 24 on high efficacy therapy. History of optic neuritis was associated with lower baseline GC-IPL thickness (p = 0.003). Higher baseline GC-IPL thickness was associated with increased rate of GC-IPL thinning (p = 0.009). Age, disease duration, and ethnicity were not predictors of baseline RNFL or GC-IPL thickness, or rate of atrophy of these layers. ConclusionsThere were no differences in rate of GC-IPL atrophy between patients with RRMS on different treatments in this cohort. Age, disease duration, and ethnicity also did not predict retinal atrophy. History of ON was associated with reduced GC-IPL thickness at baseline, consistent with previous research. Rate of GC-IPL thinning was higher for subjects with higher baseline GC-IPL thickness, suggesting a plateau effect.

Changes in and the association of retinal blood perfusion and retinal nerves in diabetic patients without retinopathy.

To explore intraretinal blood flow perfusion and nerve changes, as well as the correlation between them, in diabetic patients without diabetic retinopathy (NDR). Eighty-six NDR patients (86 eyes) who attended the ophthalmology clinic between December 2019 and December 2021 were included. Sixty-four eyes of 64 healthy examined controls in the same period were selected as the control group. The patients underwent routine ophthalmological examination, optical coherence tomography (OCT) and OCT angiography. The average thickness, minimum thickness and thickness of each quadrant except for the superior temporal quadrant of the ganglion cell-inner plexiform layer (GCIPL) in the macular area of the affected eyes in the NDR group were lower than that of the tested eyes in the control group (P < 0.05). The average retinal nerve fibre layer (RNFL) thickness of the NDR group and the superior, inferior and nasal quadrants around the optic disc of the affected eyes in the NDR group were lower compared with the tested eyes in the control group (P < 0.001, P = 0.003, P = 0.001, P = 0.009). The mean vessel length density in the parafoveal and perifoveal areas in the NDR group was positively associated with the mean GCIPL thickness in the macular area (ρ = 0.265, ρ = 0.257 and P < 0.001). No blood flow perfusion parameters in the NDR group were correlated with the RNFL thickness of the corresponding quadrant around the optic disc (P > 0.05). In diabetic patients without diabetic retinopathy, the superficial retinal vessel density in the macular area positively correlated with GCIPL thickness, and the superficial retinal vessel density around the optic disc was not correlated with RNFL thickness.

Influence of Multiple Anti-VEGF Injections on Retinal Nerve Fiber Layer and Ganglion Cell-Inner Plexiform Layer Thickness in Patients with Exudative Age-Related Macular Degeneration.

Backgrounds and Objectives: To analyze the influence of multiple anti-VEGF intravitreal injections for exudative age-related macular degeneration on the thickness of peripapillary retinal nerve fiber layer (RNFL) and macular ganglion cell-inner plexiform layer (GC + IPL) using spectral domain optical coherence tomography (SD-OCT). Materials and Methods: A prospective interventional study of consecutive patients treated with intravitreal bevacizumab (IVB) was performed. Average and sectorial values of RNFL and GC + IPL thickness were recorded using Cirrus SD-OCT at 0, 6, 12, and 24 months. Patients suffering from any ocular disease that could affect RNFL or GC + IPL thickness were excluded. Results: A total of 135 patients (70 women and 65 men, aged 65 ± 15 years) were included. The average number of injections per patient was 12.4 ± 2.4. Average RNFL and GC + IPL thickness prior to the first injection (87.6 ± 12.2 and 47.2 ± 15.5 respectively), and after 24-month follow-up (86.2 ± 12.6 and 46.7 ± 11.9 respectively) did not differ significantly (p &gt; 0.05). There was a significant decrease in GC2, GC5 segments, and minimum GC + IPL thickness. Conclusion: Repeated anti-VEGF treatment did not cause significant changes in the thickness of RNFL and GC + IPL layers over a period of 24 months. The detected decrease in GC2 and GC5 sectors, as well as in minimum GC + IPL thickness, could be a sign of ganglion cell damage induced by the treatment or could occur during the natural course of the disease.

Effects of Blood Pressure and Arterial Stiffness on Retinal Neurodegeneration: Cross-Sectional and Longitudinal Evidence From UK Biobank and Chinese Cohorts.

Hypertension might be a modifiable risk factor for neurodegeneration diseases. However, the associations between blood pressure (BP), arterial stiffness index and retinal neurodegeneration remain unclear. This study used cross-sectional data from the United Kingdom BioBank (UKB) and longitudinal data from the Chinese Ocular Imaging Project (COIP). The macular ganglion cell-inner plexiform layer thickness (mGCIPLT) and macular retinal nerve fiber layer thickness were measured using spectral domain optical coherence tomography imaging. Swept-source optical coherence tomography was performed to obtain the longitudinal trajectory of the mGCIPLT and peripapillary retinal nerve fiber layer thickness in the COIP cohort. Multivariable linear models were used to analyze the associations between BP and retinal measurements. In a cross-sectional analysis of 22 801 participants from UKB, thinner mGCIPLT was related to higher systolic BP (β: -0.103 [-0.146 to -0.061]; P<0.001), and higher diastolic BP (β: -0.191 [-0.265 to -0.117]; P<0.001), and was significantly associated with higher mean arterial pressure (β: -0.174 [-0.238 to -0.109]; P<0.001) and higher mean pulse pressure (β: -0.080 [-0.139 to -0.020]; P=009). In a longitudinal analysis of 2012 eligible COIP participants, higher levels of baseline systolic BP, diastolic BP, mean arterial pressure, and mean pulse pressure were associated with faster thinning in mGCIPLT and peripapillary retinal nerve fiber layer thickness (all P<0.001). The strongest association was the effect of mean arterial pressure on mGCIPLT (β: -0.118 [-0.175 to -0.061]; P<0.001). The results of the analysis of macular retinal nerve fiber layer thickness and peripapillary retinal nerve fiber layer thickness were consistent with those of mGCIPLT. BP levels were independently and consistently associated with various retinal neurodegenerative exacerbations.

Quantitatively Evaluating the Relationships between Insulin Resistance and Retinal Neurodegeneration with Optical Coherence Tomography in Early Type 2 Diabetes Mellitus

Introduction: The aim of this study was to quantitatively assess retinal neurodegenerative changes with optical coherence tomography (Cirrus HD-OCT) in type 2 diabetes mellitus (T2DM) patients without diabetic retinopathy (DR) and evaluate their relationships with insulin resistance (IR) and associated systemic indicators. Methods: 102 T2DM patients without DR and 48 healthy controls were included in this observational cross-sectional study. The OCT parameters of macular retinal thickness (MRT) and ganglion cell-inner plexiform layer (GCIPL) thicknesses were evaluated between diabetic and normal eyes. The receiver operating characteristics (ROC) curve was generated to evaluate the discrimination power of early diabetes. Correlation and multiple regression analysis were performed between ophthalmological parameters and T2DM-related demographic and anthropometric variables, and serum biomarkers and homeostasis model assessment of insulin resistance (HOMA-IR) scores. Results: MRT and GCIPL thicknesses showed significant thinning in patients, especially in inferotemporal area. High body mass index (BMI) correlated with decreased GCIPL thicknesses and elevated intraocular pressure (IOP). A negative correlation between waist-to-hip circumference ratio (WHR) and GCIPL thicknesses was also found. High-density lipoprotein (HDL) and fasting C-peptide (CP0) were associated with GCIPL thickness but only in inferotemporal region (r = 0.20, p = 0.04; r = −0.20, p = 0.05, respectively). Multiple regression analysis showed that increased HOMA-IR scores independently predicted both average (β = −0.30, p = 0.05) and inferotemporal (β = −0.34, p = 0.03) GCIPL thinning. Conclusion: Retinal thinning in early T2DM was associated with obesity-related metabolic disorders. IR as an independent risk factor for retinal neurodegeneration may increase the risk of developing glaucoma.

Topographic Differences in Superficial Macular Vessel Density in Eyes with Early Primary Open-Angle Glaucoma and Normal Tension Glaucoma

Introduction: The aim of the study was to compare macular vascular microcirculation in early primary open-angle glaucoma (POAG), normal tension glaucoma (NTG), and normal subjects. Methods: 99 patients with early glaucoma (99 eyes: 60 POAG and 39 NTG) and 78 normal subjects were included. All subjects underwent optical coherence tomography angiography scan at 6 × 6 mm macular area. Macular vessel density (VD) and perfusion density (PD) and 9 sectors were compared between the controls, POAG, and NTG groups. Linear regression analysis was used to investigate the relationship between VD and other variables including macular PD, signal strength (SS), and mean macular ganglion cell-inner plexiform layer (mGCIPL) thickness. Results: Significant losses in total area of VD and PD were detected in POAG and NTG groups compared to the controls (all p < 0.01). There were no significant differences in all inner sectors of macular VD and PD between POAG and controls (all p > 0.05). Except for outer-nasal sector, all other outer sectors of macular VD and PD were significantly lower in POAG than in the controls (all p < 0.01). The inferior-inner sector and all outer sectors of VD and PD were significantly lower in NTG than in the controls (all p < 0.01). Macular VD was significantly correlated with macular PD (r = 0.99, p < 0.001), SS (r = 0.60, p < 0.001), and mGCIPL thickness (r = 0.51, p < 0.001). Conclusions: Macular microcirculation declined significantly in early POAG and NTG patients. Macular microcirculation loss in the NTG group was more central and nasal compared with that in the POAG group. A decrease in macular VD was correlated with lower macular PD, lower SS, and thinner mGCIPL thickness.

Association of paramagnetic rim lesions and retinal layer thickness in patients with multiple sclerosis

Background: Paramagnetic rim lesions (PRLs) are chronic active lesions associated with a more severe disease course in multiple sclerosis (MS). Retinal layer thinning measured by optical coherence tomography (OCT) is a biomarker of neuroaxonal damage associated with disability progression in MS. Objective: We aimed to determine a potential association between OCT parameters (peripapillary retinal nerve fiber layer (pRNFL) ganglion cell-inner plexiform layer (GCIPL), inner nuclear layer (INL) thickness), and PRLs in patients with MS (pwMS). Methods: In this cross-sectional retrospective study, we included pwMS with both 3T brain MRI and an OCT scan. Regression models were calculated with OCT parameters (pRNFL, GCIPL, INL) as dependent variables, and the number of PRLs as an independent variable adjusted for covariates. Results: We analyzed data from 107 pwMS (mean age 34.7 years (SD 10.9), 64.5% female, median disease duration 6 years (IQR 1–13), median EDSS 1.5 (range 0–6.5)). Higher number of PRLs was associated with lower pRNFL (β = −0.18; 95% CI −0.98, −0.03; p = 0.038) and GCIPL thickness (β = −0.21; 95% CI −0.58, −0.02; p = 0.039). Conclusion: The association between higher number of PRLs and lower pRNFL and GCIPL thicknesses provides additional evidence that pwMS with PRLs are affected by a more pronounced neurodegenerative process.

Border tissue morphology is associated with macular ganglion cell thickness in open-angle glaucoma

Externally oblique border tissue (EOBT) configuration is topographically associated with glaucomatous damage in the optic nerve head. We investigated the relationship between the EOBT characteristics and macular retinal ganglion cell (RGC) thickness in patients with open-angle glaucoma (OAG). A total of 149 eyes with OAG that had an EOBT observed on optical coherence tomography exams were included. After determining the maximum EOBT length and angular location of the maximal EOBT length, we analyzed their correlation with macular ganglion cell inner plexiform layer (GCIPL) and peripapillary retinal nerve fiber layer (pRNFL) thickness. The macular GCIPL and pRNFL thickness were compared based on the angular location of the longest EOBT, and their association was assessed using multivariable regression analysis. Maximum EOBT length was significantly correlated with macular GCIPL thickness, but not with pRNFL thickness. Macular GCIPL was thinnest in eyes with EOBT located in a temporal direction to the optic disc. Longer maximum EOBT and temporally elongated EOBT were independently associated with a thinner macular GCIPL in the multivariable regression analysis. These suggest that temporal elongation of the EOBT may increase the stress and strain on the RGCs derived from the macula and make RGCs more susceptible to glaucoma-inducing damage.