Ganglion Cell-inner Plexiform Layer Thickness Research Articles

Clinical efficacy of optical coherence tomography parameters to predict the visual field outcome following pituitary adenoma surgery.

To investigate the factors affecting visual field recovery in patients with pituitary adenoma following surgical removal, both eyes of 35 patients with pituitary adenoma who had been followed up for > six months post-surgery were retrospectively analyzed. Pre- and post-operative visual acuity, visual field test, retinal nerve fiber layer (RNFL), and ganglion cell inner plexiform layer (GCIPL) thickness were investigated. The average age of the 35 patients was 58.3 ± 11.5 years. Preoperatively, 30 eyes (mean average RNFL thickness, 99.73 ± 5.89 μm) and 40 eyes (mean average RNFL thickness, 77.55 ± 8.35 μm) were included in the thick (≥ 90 μm) and thin RNFL group (< 90 μm), respectively. In the thick RNFL group, pre- and post-operative mean deviation (MD) and pattern standard deviation (PSD) were favorable (all p < 0.001), and the proportion of eyes of postoperative MD change which were stable or improved was greater than in the thin RNFL group (p = 0.042). Preoperative MD, RNFL (except nasal quadrant) and GCIPL thickness were positively correlated to postoperative MD values (all, p < 0.05). Preoperative MD and temporal RNFL thickness were significantly correlated with postoperative MD change rate (p = 0.03 and 0.04, respectively). Preoperative GC IPL thickness and postoperative MD change rate were not significantly correlated (p = 0.61). Using univariate regression analysis, preoperative best corrected visual acuity (Odds ratio [OR], 0.050; p < 0.001), tumor volume (OR, 1.110, p = 0.002), higher preoperative MD values (OR, 0.858; p < 0.001), lower preoperative PSD values (OR, 1.169, p = 0.002), thick RNFL (OR, 0.215; p = 0.003) and thick GCIPL (OR, 0.305, p = 0.018) were significantly associated with a good visual field outcome following surgery. According to multivariate analysis, any other parameters were not significant. In patients with thick RNFL, postoperative MD values were better than in the thin RNFL group. Eyes with preoperative higher MD and thick temporal RNFL showed more improvement in their visual fields postoperative. Preoperative thick RNFL could be a potential predictor of visual field recovery following TSA-TR, while macular GCIPL thickness does not appear to be a reliable predictor.

Examination of optical coherence tomography findings in patients with pregabalin use disorder.

Pregabalin abuse is a rapidly growing health problem worldwide, and little is known about the effects of prolonged high-dose use in patients with pregabalin use disorder. In this study, the effects of pregabalin abuse on retinal layers were investigated in patients with pregabalin use disorder (PGUD). This study included 35 controls and 34 patients with PGUD, according to Diagnostic and Statistical Manual of Mental Disorders (DSM)-5 criteria. Optic coherence tomography (OCT) measurements including the retinal nerve fiber layer (RNFL), ganglion cell layer-inner plexiform layer (GCL-IPL) and ganglion cell complex (GCC) were performed. RNFL thickness was evaluated in four quadrants (inferior, superior, nasal, temporal). GCL-IPL and GCC thickness were evaluated in six sectors (superior, superonasal, inferonasal, inferior, inferotemporal, superotemporal). GCC inferonasal (p = 0.040, r = 0.354), GCC inferior (p = 0.018, r = 0.402) GCL-IPL inferior (p = 0.031, r = 0.370) and GCL-IPL inferotemporal (p = 0.029, r = 0.376) thickness were positively correlated with the duration of pregabalin use. There was no significant sector or quadrant-wise difference between groups (p > 0.05). Our findings emphasized the drug's potential neuroprotective effect. It should be taken into consideration that neurodegenerative changes due to substance use disorder occur with long-term. Longitudinal prospective studies investigating dose-duration relationship are needed.

Angioarchitectural alterations in the retina and choroid in frontotemporal dementia.

Frontotemporal dementia (FTD) is a progressive neurodegenerative disorder that affects the frontal and temporal lobes of the brain, leading to cognitive decline and personality changes. The objective of this cross-sectional study was to characterize angioarchitectural changes in the retina and choroid of individuals with FTD compared to cognitively normal controls using optical coherence tomography (OCT) and OCT angiography (OCTA). Cross-sectional comparison of patients with FTD and controls with normal cognition. All participants underwent Mini-Mental State Examination (MMSE) at the time of imaging. Outcome measures included OCT parameters: retinal nerve fiber layer (RNFL) thickness, ganglion cell layer-inner plexiform layer (GC-IPL) thickness, central subfield thickness (CST), subfoveal choroidal thickness (SFCT), choroidal vascularity index (CVI); and OCTA superficial capillary plexus parameters: foveal avascular zone (FAZ) area, 3x3mm and 6x6mm macular perfusion density (PD) and vessel density (VD), 4.5x4.5mm peripapillary capillary perfusion density (CPD) and capillary flux index (CFI). Generalized estimating equation analysis was used to account for the inclusion of 2 eyes from the same participant. 29 eyes of 19 patients with FTD and 85 eyes of 48 controls were analyzed. In FTD, 3x3mm macular PD (p = 0.02) and VD (p = 0.02) and CFI (p = 0.01) were reduced compared to controls. There was no difference in average 4.5x4.5mm CPD, RNFL thickness, GC-IPL thickness, CST, SFCT, CVI, FAZ, or 6x6mm VD or PD between FTD and controls (all p > 0.05); however, there was a trend toward lower macular 6x6mm PD and VD in patients with FTD. Decline of peripapillary and macular OCT and OCTA parameters merit further investigation as potential biomarkers for FTD detection. Noninvasive retinal and choroidal imaging may hold promise for earlier detection, and future longitudinal studies will clarify their role in monitoring of FTD.

Total retinal thickness is an important factor in evaluating diabetic retinal neurodegeneration

ObjectiveMacular retinal nerve fibre layer (mRNFL) and ganglion cell-inner plexiform layer thickness (GC-IPL) measurements are important markers of diabetic retinal neurodegeneration (DRN). In this cross-sectional study, we aimed to quantify...

Discriminating Diseases Mimicking Normal-Tension Glaucoma (NTG) from NTG.

Background/Objectives: The aim of this study was to identify the most reliable ocular exam and establish a threshold for deciding whether to perform neuroimaging in order to screen for diverse diseases other than normal-tension glaucoma (NTG). A retrospective, observational, comparative study was used. Methods: In total, 106 individuals with atypical features of NTG who underwent glaucoma assessments and contrast-enhanced MRI of the brain or orbit were included. The criteria for atypical NTG included the following: (1) unilateral normal-tension glaucoma, (2) visual field (VF) damage inconsistent with optic disc appearance, (3) fast VF progression, (4) worsening of visual acuity, (5) optic disc pallor, (6) scotoma restricted by a vertical line, and (7) central scotoma. Glaucoma evaluations included measurements of visual acuity, intraocular pressure, central corneal thickness, axial length, cup-disc ratio, retinal nerve fiber layer (RNFL) thickness, ganglion cell-inner plexiform layer (GCIPL) thickness, mean deviation (MD), and visual field index (VFI). Statistical analyses involved independent t-tests, receiver operating characteristic (ROC) curves, and area under the curve (AUC) in order to differentiate neuro-ophthalmological conditions from NTG, compare the diagnostic power of each factor, and determine the cut-off value. Results: Relatively fewer diagnoses of non-glaucomatous diseases were associated with unilateral NTG, the worsening of VA, and central scotoma. Factors such as rapid visual field progression, optic disc pallor, and scotoma restricted by a vertical line had a relatively higher diagnostic rate of non-glaucomatous diseases. There were significant differences in average RNFL and GCIPL thicknesses at the nasal quadrant between NTG and NTG-mimicking conditions. Only the GCIPL thickness at the nasal quadrant had reliable power for discriminating between neuro-ophthalmological disease and NTG. For the GCIPL thickness at the nasal quadrant, the AUC was 0.659, and the cut-off value was 65.75. Conclusions: When deciding whether to proceed with imaging, such as carrying out an MRI test, for NTG patients with atypical NTG characteristics, it would be advisable to consider the nasal sector cut-off value of GCIPL thickness.

Comparison of ganglion cell-inner plexiform layer thickness among patients with intermittent exotropia according to fixation preference: a retrospective observational study.

This study was performed to compare the thickness of the ganglion cell-inner plexiform layer (GCIPL) depending on the presence or absence of fixation preference in patients with intermittent exotropia (IXT) with refractive values close to emmetropia and with no amblyopia. The study recruited pediatric patients diagnosed with IXT with a spherical equivalent within ±1.25 diopter and no amblyopia. The patients were categorized into two groups: a monocular exotropia group with fixation preference and an alternating exotropia group without fixation preference. GCIPL thickness was measured using spectral domain optical coherence tomography, and the macula was divided into nine sectors according to the Early Treatment Diabetic Retinopathy Study (ETDRS). GCIPL thickness in each sector was compared between the monocular and alternating exotropia groups. In the monocular exotropia group, GCIPL thickness was significantly thinner in the dominant eye than in the nondominant eye in the S1 sector (91.2±7.4 μm vs. 93.3±5.2 μm, p=0.019). However, in the alternating exotropia group, there were no significant differences between the eyes across all ETDRS sectors. When comparing the interocular differences in GCIPL thickness between the two groups, the monocular exotropia group (absolute value of the dominant eye minus the nondominant eye) exhibited significantly greater differences in several ETDRS sectors than the alternating exotropia group (absolute value of the right eye minus the left eye). The significant interocular difference in GCIPL thickness in the monocular exotropia group suggests that fixation preference may influence the anatomical structure of the macula in patients with IXT.

A Novel Approach To Predict Glaucomatous Impairment in the Central 10° Visual Field, Excluding the Effect of Cataract.

Our previous study predicted genuine glaucomatous visual field (VF) impairment in the central 10° VF, excluding the effect of cataract, using visual acuity (VA) and global indexes of VF more accurately than pattern deviation (PD). This study aimed to improve the accuracy by using pointwise total deviation (TD) values with the machine-learning method of random forest model (RFM) and to investigate whether incorporating optical coherence tomography-measured ganglion cell-inner plexiform layer (GCIPL) thickness is useful. This retrospective study included 89 eyes with open-angle glaucoma that underwent successful cataract surgery (with or without iStent implantation or ab interno trabeculotomy). Postoperative TD in each of the 68 VF points was predicted using preoperative (1) PD, (2) VA and VF with a linear regression model (LM), and (3) VA and VF with RFM, and averaged as predicted mean TD (mTDpost). Further prediction was made by incorporating the preoperative GCIPL into the best model. The mean absolute error (MAE) between the actual and predicted mTDpost with RFM (1.25 ± 1.03 dB) was significantly smaller than that with PD (3.20 ± 4.06 dB, p < 0.01) and LM (1.42 ± 1.06 dB, p < 0.05). The MAEs with the model incorporating GCIPL into RFM (1.24 ± 1.04 dB) and RFM were not significantly different. Accurate prediction of genuine glaucomatous VF impairment was achieved using pointwise TD with RFM. No merit was observed by incorporating the GCIPL into this model. This pointwise RFM could clinically reduce cataract effect on VF.

Macular exudate in idiopathic intracranial hypertension affects outer retina and visual acuity

BackgroundOptical coherence tomography (OCT) is suggested as a potential tool for retinal biomarkers in idiopathic intracranial hypertension (IIH). We explored how macular exudate (ME) affects retinal structure in IIH and...

Inner retinal layer thickness alterations in adult and pediatric patients with neurofibromatosis 1

This study compared the thickness of each intraretinal layer in patients with neurofibromatosis 1 (NF1) and controls to analyze the association between intraretinal layer thickness and visual function. The macular spectral-domain optical coherence tomography volumetric dataset obtained from 68 eyes (25 adult eyes, 43 pediatric eyes) with NF1 without optic glioma and 143 control eyes (100 adult eyes, 43 pediatric eyes) was used for image auto-segmentation. The intraretinal layers segmented from the volumetric data included the macular retinal nerve fiber layer (RNFL), ganglion cell-inner plexiform layer (GCIPL), inner nuclear layer, outer plexiform layer, outer nuclear layer, and photoreceptor layer. Cases and controls were compared after adjusting for age, sex, refractive error, and binocular use. The association between retinal layer thickness and visual acuity was also analyzed. The GCIPL was significantly thinner in both adult and pediatric patients with NF1 compared with healthy controls. Average RNFL and GCIPL thicknesses were associated with visual acuity in adult patients with NF1. In pediatric patients, average GCIPL thickness was associated with visual acuity. These results suggest that changes in the inner retinal layer could be a biomarker of the structural and functional status of patients with NF1.

Retinal and Choroidal Phenotypes Across Novel Subtypes of Type 2 Diabetes Mellitus

PurposeThis study aimed to investigate longitudinal changes in choroidal thickness (CT) and ganglion cell-inner plexiform layer thickness (GC-IPLT) across distinct phenotypes of type 2 diabetes mellitus (T2DM) patients. DesignProspective observational cohort study. MethodsT2DM patients were categorized into five groups (SAID, SIDD, SIRD, MOD, and MARD) using K-means clustering based on β-cell function and insulin resistance. Swept-source optical coherence tomography measured baseline and 4-year follow-up CT and GC-IPLT. Linear mixed-effects models assessed absolute and relative changes in CT and GC-IPLT across subtypes. ResultsOver a median 4.11-year follow-up, CT and GC-IPLT decreased significantly across all groups. Choroidal thinning rates were most pronounced in SIDD (-6.5±0.53 µm/year and -3.5±0.24%/year) and SAID (-6.27±0.8 µm/year and -3.19±0.37%/year), while MARD showed the slowest thinning (-3.63±0.34 µm/year and -1.98±0.25%/year). SIRD exhibited the greatest GC-IPLT loss (-0.66±0.05 µm/year and -0.91±0.07%/year), with the least in SIDD (-0.36±0.05 µm/year and -0.49±0.07%/year), all statistically significant (Ps < 0.001). Adjusted for variables, SIDD and SAID groups showed faster CT thinning than MARD [-2.57 µm/year (95% CI: -4.16 to -0.97; P=0.002) and -2.89 µm/year (95% CI: -4.12 to -1.66; P<0.001), respectively]. GC-IPLT thinning was notably accelerated in SIRD versus MARD, but slowed in SIDD relative to MARD [differences of -0.16 µm/year (95% CI: -0.3 to -0.03; P=0.015) and 0.15 µm/year (95% CI: 0.03 to 0.27; P=0.015), respectively]. Stratified analysis revealed significant differences among non-DR groups. ConclusionsMicrovascular damage in the choroid is associated with SIDD patients, whereas early signs of retinal neurodegeneration are evident in SIRD patients. All these changes may precede the onset of DR.

Inter-eye asymmetry of microvascular density in patients on hydroxychloroquine therapy by optical coherence tomography angiography

AimsTo explore the inter-eye retinal microvascular density asymmetry of patients on hydroxychloroquine (HCQ) therapy through optical coherence tomography angiography (OCTA). Methods40 subjects were enrolled in this cross-sectional study, including 20 systemic lupus erythematasus patients currently treated with HCQ (40 eyes) and 20 age- and sex-matched normal controls (NCs, 40 eyes). OCTA images were obtained to measure macular and peripapillary mircrovasculatures and microstructures, including vessel density, retinal nerver fiber layer thickness, and peripapillary ganglion cell-inner plexiform layer thickness. The absolute values of the difference between right and left eyes were taken as a measure of inter-eye asymmetry. ResultsMacular whole image vessel density (wiVD-M) and perifoveal vessel density (pfVD) of superficial capillary plexus (SCP) were notably reduced in both the right and left eyes of the HCQ treatment group compared with NCs. Specifically, SLE patients treated with HCQ have higher inter-eye asymmetry of wiVD-M of SCP (2.28 ± 1.03 vs 1.27 ± 0.79, p < 0.01) and pfVD of SCP (2.55 ± 1.26 vs 1.78 ± 1.06, p = 0.04) compared with NCs. There were no significant differences in inter-eye asymmetry of structure parameters. Inter-eye asymmetry of wiVD-M of SCP (AUC = 0.80, p < 0.01) and pfVD of SCP (AUC = 0.71, p = 0.02) exhibited greater discrimination power. ConclusionSLE Patients treated with HCQ exhibited a notably higher inter-eye vessel density asymmetry compared to that of NCs. Thus, inter-eye vessel density asymmetry could be used to screen for HCQ retinal toxicity.

LONGITUDINAL CHANGE OF RETINAL LAYER THICKNESS IN COGNITIVELY NORMAL ELDERLY SUBJECTS: Population-Based Cohort Study.

To identify longitudinal retinal layer thickness changes in normal eyes of cognitively healthy elderly people. Post hoc analysis was performed on 57 cognitively healthy elderly participants from the population-based Korean Longitudinal Study on Health and Aging and Korean Longitudinal Study on Cognitive Aging and Dementia cohort studies who underwent baseline and final optical coherence tomography 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. The mean age of subjects was 75.1 years and the mean follow-up period was 55.9 months. Among the analyzed retinal layers, both the ganglion cell-inner plexiform layer and the outer nuclear layer at all 1 mm, 2 mm, and 3 mm points showed a statistically significant decrease in thickness at the final visit compared with 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%), and -1.1 µm/year at 3 mm (total -9.7%) for ganglion cell-inner plexiform layer and -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 outer nuclear layer. Aging plays a significant role in the reduction of ganglion cell-inner plexiform layer and outer nuclear layer thicknesses in cognitively healthy elderly individuals.

The thickness of the retinal nerve fiber layer, macula, and ganglion cell-inner plexiform layer in people with drug-resistant epilepsy.

Using Optical coherence tomography (OCT), we evaluated the association between peripapillary retinal nerve fiber, macular thickness, macular ganglion cell-inner plexiform layer, and drug resistance. In this cross-sectional study, we recruited people diagnosed with epilepsy and healthy controls. People with epilepsy were further stratified as drug-resistant or non-drug-resistant based on their response to anti-seizure medications. OCT measurements were conducted, and findings in right eye were analyzed. Fifty-one drug-resistant participants, 37 non-drug-resistant, and 45 controls were enrolled. The average peripapillary retinal nerve fiber layer, ganglion cell-inner plexiform layer, and macular thickness were thinner in the epilepsy groups than in controls. The drug-resistant group had significantly lower average ganglion cell-inner plexiform layer thickness (p = 0.004) and a higher proportion of abnormal/borderline GC/IPL thickness (p = 5.40E-04) than the non-drug-resistant group. Nevertheless, no significant differences were seen between the average thickness of peripapillary retinal nerve fiber and macular thickness. The temporal sectors of these three parameters were also significantly thinner in the drug-resistant group than in the non-drug-resistant. In a multivariate regression model, drug resistance was an independent predictor of reduced ganglion cell-inner plexiform thickness (Odds ratios OR = 10.25, 95% CI 2.82 to 37.28). Increased seizure frequency (r = -0.23, p = 0.039) and a higher number of anti-seizure medications ever used (r = -0.27, p = 0.013) were negatively associated with ganglion cell-inner plexiform layer thickness. Individuals with drug-resistant epilepsy had a consistent reduction in average ganglion cell-inner plexiform layer thickness and the temporal sector of peripapillary retinal nerve fiber layer and macular thickness. This suggests that ganglion cell-inner plexiform layer thickness could potentially serve as an indicator of the burden of drug resistance, as it correlated with reduced thickness in individuals having more frequent seizures and greater exposure to ASMs. In our study, we used a special tool called OCT to measure how thick the retina is in people with epilepsy and in healthy control. We found that the retina was consistently thinner in all areas for those with epilepsy compared to healthy control. Particularly, a specific layer called the ganglion cell-inner plexiform layer was a lot thinner in the group that didn't respond to medications, and this thinning was related to how often seizures occurred and how much medications were taken. Also, certain parts of the retina were thinner in the drug-resistant group.

Macular structural integrity estimates are associated with Parkinson’s disease genetic risk

BackgroundOptical coherence tomography (OCT) is a non-invasive technique to measure retinal layer thickness, providing insights into retinal ganglion cell integrity. Studies have shown reduced retinal nerve fibre layer (RNFL) and ganglion cell inner plexiform layer (GCIPL) thickness in Parkinson’s disease (PD) patients. However, it is unclear if there is a common genetic overlap between the macula and peripapillary estimates with PD and if the genetic risk of PD is associated with changes in ganglion cell integrity estimates in young adults.MethodWestern Australian young adults underwent OCT imaging. Their pRNFL, GCIPL, and overall retinal thicknesses were recorded, as well as their longitudinal changes between ages 20 and 28. Polygenic risk scores (PRS) were estimated for each participant based on genome-wide summary data from the largest PD genome-wide association study conducted to date. We further evaluated whether PD PRS was associated with changes in thickness at a younger age. To evaluate the overlap between retinal integrity estimates and PD, we annotated and prioritised genes using mBAT-combo and performed colocalisation through the GWAS pairwise method and HyPrColoc. We used a multi-omic approach and single-cell expression data of the retina and brain through a Mendelian randomisation framework to evaluate the most likely causal genes. Genes prioritised were analysed for missense variants that could have a pathogenic effect using AlphaMissense.ResultsWe found a significant association between the Parkinson’s disease polygenic risk score (PD PRS) and changes in retinal thickness in the macula of young adults assessed at 20 and 28 years of age. Gene-based analysis identified 27 genes common to PD and retinal integrity, with a notable region on chromosome 17. Expression analyses highlighted NSF, CRHR1, and KANSL1 as potential causal genes shared between PD and ganglion cell integrity measures. CRHR1 showed consistent results across multiple omics levels.InterpretationOur findings suggest that retinal measurements, particularly in young adults, could be a potential marker for PD risk, indicating a genetic overlap between retinal structural integrity and PD. The study highlights specific genes and loci, mainly on chromosome 17, as potential shared etiological factors for PD and retinal changes. Our results highlight the importance of further longitudinal studies to validate retinal structural metrics as early indicators of PD predisposition.

Multimodal Retinal Imaging Classification for Parkinson's Disease Using a Convolutional Neural Network.

Changes in retinal structure and microvasculature are connected to parallel changes in the brain. Two recent studies described machine learning algorithms trained on retinal images and quantitative data that identified Alzheimer's dementia and mild cognitive impairment with high accuracy. Prior studies also demonstrated retinal differences in individuals with PD. Herein, we developed a convolutional neural network (CNN) to classify multimodal retinal imaging from either a Parkinson's disease (PD) or control group. We trained a CNN to receive retinal image inputs of optical coherence tomography (OCT) ganglion cell-inner plexiform layer (GC-IPL) thickness color maps, OCT angiography 6 × 6-mm en face macular images of the superficial capillary plexus, and ultra-widefield (UWF) fundus color and autofluorescence photographs to classify the retinal imaging as PD or control. The model consists of a shared pretrained VGG19 feature extractor and image-specific feature transformations which converge to a single output. Model results were assessed using receiver operating characteristic (ROC) curves and bootstrapped 95% confidence intervals for area under the ROC curve (AUC) values. In total, 371 eyes of 249 control subjects and 75 eyes of 52 PD subjects were used for training, validation, and testing. Our best CNN variant achieved an AUC of 0.918. UWF color photographs were the most effective imaging input, and GC-IPL thickness maps were the least contributory. Using retinal images, our pilot CNN was able to identify individuals with PD and serves as a proof of concept to spur the collection of larger imaging datasets needed for clinical-grade algorithms. Developing machine learning models for automated detection of Parkinson's disease from retinal imaging could lead to earlier and more widespread diagnoses.

Optic Nerve Head Morphology and Macula Ganglion Cell Inner Plexiform Layer Thickness in Axially Anisometropic Rhesus Monkeys.

The purpose of this study was to determine the effects of axial elongation on optic nerve head morphology and macula inner retinal thickness in young rhesus monkeys. Both eyes of 26 anisometropic, 1-year-old rhesus monkeys were imaged using optical coherence tomography (OCT). Before imaging, the animals were sedated, their eyes were dilated, and axial length was measured using an optical biometer. OCT imaging included a 20 degrees, 24-line radial scan centered on the optic nerve head (ONH) and two 20 degrees × 20 degrees raster scans, one centered on the ONH and the other on the macula. Radial scans were analyzed using programs written in MATLAB to quantify the Bruch's membrane opening (BMO) area and position, minimum rim width (MRW), anterior lamina cribrosa surface (ALCS) position, size of any scleral crescent, circumpapillary retinal nerve fiber layer (RNFL), and choroid thickness (pCh). Macula total retinal thickness (mTRT) and ganglion cell inner plexiform layer (GCIPL) thicknesses were quantified from macula scans. Linear least square regression was determined for OCT measures and axial length of the right eye, and for inter-eye differences. Animals were 341 ± 18days old at the time of imaging. BMO area (R2 = 0.38), ALCS position (R2 = 0.45), scleral crescent area (R2 = 0.35), pCh thickness (R2 = 0.21), mTRT (R2 = 0.24), and GCIPL thickness (R2 = 0.16) were correlated with the axial length (all P < 0.05). For each of these parameters, the right-eye regression slope did not differ from the slope of the interocular difference (P > 0.57). There are posterior segment morphological differences in anisometropic rhesus monkeys related to axial length. Whether these differences increase the risk of pathology remains to be investigated.

Influence of Carotid Artery Stenting on the Retina and Choroid.

The effect of carotid artery stenting in patients with unilateral carotid artery stenosis on the retina and choroid was evaluated using swept-source optical coherence tomography angiography (SS-OCTA). SS-OCTA examination was conducted before stenting and 4days and 3months after stenting. The retinal nerve fiber layer, ganglion cell-inner plexiform layer (GCIPL), inner nuclear layer, superficial vascular complex (SVC), deep vascular complex (DVC), choroidal vascular volume (CVV), and choroidal vascular index were measured. Repeated-measures analysis of variance was performed to assess the impact of carotid artery stenting on optical coherence tomography angiography (OCTA) metrics. At baseline, 303 eyes from 160 patients (61.82 ± 9.98years; 85.29% males) were enrolled. SVC and DVC densities and CVV were lower in ipsilateral eyes (stenosed side) compared to contralateral eyes (all P < 0.05). Four days after stenting, a significant increase was seen in SVC density in ipsilateral eyes (P < 0.05) while a significant increase was seen in CVV in ipsilateral eyes and contralateral eyes (both P < 0.05). Three months after stenting (63 patients with 114 eyes), a significant decrease was seen in the GCIPL thickness of ipsilateral and contralateral eyes (all P < 0.001). Short term after carotid artery stenting, ipsilateral eyes showed a rapid and significant increase in SVC density and CVV. Optical coherence tomography (OCT)/OCTA measurements may have the potential to detect retinal and choroidal changes after stenting. Future research on the long-term effect of stenting on the retina and choroid will be guided by these findings.

Association between polygenic risk for schizophrenia and retinal morphology: A cross-sectional analysis of the United Kingdom Biobank

We examined the relationship between genetic risk for schizophrenia (SZ), using polygenic risk scores (PRSs), and retinal morphological alterations. Retinal structural and vascular indices derived from optical coherence tomography (OCT) and color fundus photography (CFP) and PRSs for SZ were analyzed in N = 35,024 individuals from the prospective cohort study, United Kingdom Biobank (UKB). Results indicated that macular ganglion cell-inner plexiform layer (mGC-IPL) thickness was significantly inversely related to PRS for SZ, and this relationship was strongest within higher PRS quintiles and independent of potential confounders and age. PRS, however, was unrelated to retinal vascular characteristics, with the exception of venular tortuosity, and other retinal structural indices (macular retinal nerve fiber layer [mRNFL], inner nuclear layer [INL], cup-to-disc ratio [CDR]). Additionally, the association between greater PRS and reduced mGC-IPL thickness was only significant for participants in the 40–49 and 50–59 age groups, not those in the 60–69 age group. These findings suggest that mGC-IPL thinning is associated with a genetic predisposition to SZ and may reflect neurodevelopmental and/or neurodegenerative processes inherent to SZ. Retinal microvasculature alterations, however, may be secondary consequences of SZ and do not appear to be associated with a genetic predisposition to SZ.

Exploring the relationship between 24-2 visual field and widefield optical coherence tomography data across healthy, glaucoma suspect and glaucoma eyes.

To utilise ganglion cell-inner plexiform layer (GCIPL) measurements acquired using widefield optical coherence tomography (OCT) scans spanning 55° × 45° to explore the link between co-localised structural parameters and clinical visual field (VF) data. Widefield OCT scans acquired from 311 healthy, 268 glaucoma suspect and 269 glaucoma eyes were segmented to generate GCIPL thickness measurements. Estimated ganglion cell (GC) counts, calculated from GCIPL measurements, were plotted against 24-2 SITA Faster visual field (VF) thresholds, and regression models were computed with data categorised by diagnosis and VF status. Classification of locations as VF defective or non-defective using GCIPL parameters computed across eccentricity- and hemifield-dependent clusters was assessed by analysing areas under receiver operating characteristic curves (AUROCCs). Sensitivities and specificities were calculated per diagnostic category. Segmented linear regression models between GC counts and VF thresholds demonstrated higher variability in VF defective locations relative to non-defective locations (mean absolute error 6.10-9.93 dB and 1.43-1.91 dB, respectively). AUROCCs from cluster-wide GCIPL parameters were similar across methods centrally (p = 0.06-0.84) but significantly greater peripherally, especially when considering classification of more central locations (p < 0.0001). Across diagnoses, cluster-wide GCIPL parameters demonstrated variable sensitivities and specificities (0.36-0.93 and 0.65-0.98, respectively), with the highest specificities observed across healthy eyes (0.73-0.98). Quantitative prediction of VF thresholds from widefield OCT is affected by high variability at VF defective locations. Prediction of VF status based on cluster-wide GCIPL parameters from widefield OCT could become useful to aid clinical decision-making in appropriately targeting VF assessments.

EVALUATION OF MACULAR GANGLION CELL COMPLEX USING SPECTRAL DOMAIN OPTICAL COHERENCE TOMOGRAPHY IN GLAUCOMA SUSPECT PATIENTS AND TO CORRELATE IT WITH NORMAL POPULATION

PURPOSE:. To evaluate macular ganglion cell complex in glaucoma suspect patients and normal population RESULTS The difference between values of neuroretinal rim thickness,rim area,disc area,average CDR,vertical CDR and cup volume among glaucoma suspect and normal (controls) was found to be statistically significant (p value&lt;0.001). The difference between values of superior,nasal,inferior,temporal and average RNFL thickness among glaucoma suspect and normal (controls) was found to be statistically significant(p value&lt;0.001). The difference between values of superotemporal, superior, superonasal, inferonasal, inferior, inferotemporal, average and minimum GCIPL (Ganglion cell Inner plexiform layer) thickness in µm, as estimated on OCT macula, was found to be statistically significant among glaucoma suspect patients and normal (controls) (p value &lt;0.001). Upon applying Spearman’s rho correlation coefficient test in glaucoma suspect patients for GCIPL thickness and RNFL thickness, statistically significant correlation was found between Inferior RNFL thickness with Inferotemporal GCIPL thickness(p value 0.029) and Temporal RNFL thickness with Inferotemporal GCIPL thickness .(p values 0.006). Upon applying Spearman’s rho correlation coefficient test in normal (controls) for GCIPL thickness and RNFL thickness,statistically significant correlation was found between Superior RNFL thickness with Superior GCIPL thickness(p value 0.038), Superior RNFL thickness with Superonasal GCIPL thickness (p values 0.012 ), and Average RNFL thickness with Average GCIPL thickness (p value 0.033) CONCLUSION: In our study we found there is statistically significant reduction in thickness in all measured quadrants of Macular GCIPL and RNFL in glaucoma suspect patients compared to normal. Also, a statistically significant correlation was found between Inferior RNFL thickness with Inferotemporal GCIPL thickness and Temporal RNFL thickness with Inferotemporal GCIPL thickness in glaucoma suspect patients,suggesting good diagnostic ability of inferotemporal macular GCIPL thickness.