Ganglion Cell-inner Plexiform Layer Research Articles

Optical coherence tomography in papilledema: A probe into the intracranial pressure correlation.

To study the optic nerve head characteristics on optical coherence tomography (OCT) in patients with papilledema and correlate them with intracranial pressure (ICP). A retrospective hospital-based study of 46 eyes of 23 patients with bilateral optic disc edema secondary to increased ICP. The clinical profile and the OCT features in terms of retinal nerve fiber layer thickness (RNFL), ganglion cell inner plexiform layer (GCIPL) thickness, and enhanced depth imaging (EDI) B scan images of the optic nerve head were studied and correlated with the ICP. Papilledema was secondary to idiopathic intracranial hypertension (IIH) ( n = 20), obstructive hydrocephalus ( n = 2), and communicating hydrocephalus ( n = 1). The mean ICP in 20 IIH patients was 347 mmH 2 O. The ICP and RNFL thickness in all four quadrants were found to be weakly positively correlated: superior RNFL r (38) = 0.17, P = 0.30, and nasal RNFL r (38) = 0.30, P = 0.05, inferior RNFL r (38) = 0.29, P = 0.07, and temporal RNFL, r (38) = -0.001, P = 0.99. The GCIPL layer thickness and the ICP were weakly negatively correlated in all sectors: superior (38) = -0.23, P = 0.16, superonasal, r (38) = -0.07, P = 0.67, inferonasal r (38) = -0.08, P = 0.64, inferior r (38) = -0.21, P = 0.19, inferotemporal r (38) = -0.23, P = 0.17, superotemporal, r (38) -0.21, P = 0.20. Descriptive features on the B scan, such as peripapillary hyperreflective ovoid mass-like structures and microcystic spaces, were observed most commonly with an ICP of 251-350 mmH 2 O, and the hyperreflective dots in the RNFL layer and Bruch's membrane inward denting were observed more commonly with an ICP of 351-450 mmH 2 O. The RNFL thickness in all four quadrants had a weak positive correlation, and the GCIPL layer had a weak negative correlation with the ICP. The EDI descriptive features on OCT may vary with ICP.

Retinal neurovascular alteration in type 2 diabetes with renal impairment in association with systemic arterial stiffness

BackgroundDiabetic retinopathy (DR) patients should be alert for subclinical macroangiopathy. We aimed to investigate the association between retinal neurovascular alteration and systemic arterial stiffness in type 2 diabetes mellitus (type 2 DM) patients with varying degrees of renal impairment.MethodsThe study included 170 patients with confirmed diagnosis of type 2 DM aged ≥18 years old. Renal function was assessed by estimated glomerular filtration rate (eGFR). Arterial stiffness was measured by brachial-ankle pulse wave velocity (baPWV) and ankle brachial index (ABI). Retinal neurovascular parameters were derived from Optical Coherence Tomography (OCT)/OCT-Angiography, represented by vessel density (VD Central, Inner, Outer, Full), foveal avascular zone (FAZ area and FAZ perimeter) of the superficial capillary plexus, the average of macular ganglion cell-inner plexiform layer thickness (ave mGC-IPLt) and the average of retinal nerve fiber layer thickness (aveRNFLt). The association between variables among the groups (according to renal function, diabetic retinopathy (DR) severity, and arterial stiffness categories) were analyzed by regression analysis with multiple hypothesis testing commands.ResultsOut of the 265 eyes, the mean DM duration and HbA1c were 6.21 ± 6.37 years and 8.44 ± 2.06% respectively. While the mean of eGFR, baPWV and ABI were 66.78 ± 32.80 ml/min/1.73m2, 15.49 ± 3.07 m/s, and 1.05 ± 0.12, respectively. Patients with more severe renal impairment demonstrated longer DM duration (p < 0.001), higher baPWV (p < 0.0001), and retinal vascular alteration. Proliverative DR group showed the lowest eGFR (p < 0.0001), highest baPWV (p < 0.0001), and retinal neurovascular changes. Significantly lower eGFR and retinal vascular alteration were found in the baPWV > 14 group. Some neurovascular parameters were significantly negatively correlated with baPWV; moreover, retinal neurovascular changes were also noted in the abnormal ABI group.ConclusionsThe strong association between changes in the retinal neurovascular system, DR severity, renal impairment, and arterial stiffness in type 2 DM was confirmed. Patients with more severe renal impairment had higher levels of arterial stiffness, more severe DR and retinal neurovascular alteration. Retinal neurovascular changes seen in OCT/OCTA might mimic renal microvascular alteration and systemic arterial stiffness. Therefore, assessment of baPWV and OCT/OCTA should be integrated in DR screening to enhance cardiovascular risk stratification and prognosis as well as to provide clinically useful early identification of subclinical micro- and macrovascular alterations.

Association between functional network connectivity, retina structure and microvasculature, and visual performance in patients after thalamic stroke: An exploratory multi-modality study.

Neuro-ophthalmologic symptoms and retinal changes have been increasingly observed following thalamic stroke, and there is mounting evidence indicating distinct alterations occurring in the vision-related functional network. However, the intrinsic correlations between these changes are not yet fully understood. Our objective was to explore the altered patterns of functional network connectivity and retina parameters, and their correlations with visual performance in patients with thalamic stroke. We utilized resting-state functional MRI to obtain multi-modular functional connectivity (FC), and optical coherence tomography-angiography to measure various retina parameters, such as the retinal nerve fiber layer (RNFL), ganglion cell-inner plexiform layer (GCIPL), superficial vascular complex (SVC), and deep vascular complex. Visual acuity (VA) was used as a metric for visual performance. We included 46 patients with first-ever unilateral thalamic stroke (mean age 59.74±10.02 years, 33 males). Significant associations were found between FC of attention-to-default mode and SVC, RNFL, and GCIPL, as well as between FC of attention-to-visual and RNFL (p<.05). Both RNFL and GCIPL exhibited significant associations with FC of visual-to-visual (p<.05). Only GCIPL showed an association with VA (p=.038). Stratified analysis based on a disease duration of 6 months revealed distinct and significant linking patterns in multi-modular FC and specific retina parameters, with varying correlations with VA in each subgroup. These findings provide valuable insight into the neural basis of the associations between brain network dysfunction and impaired visual performance in patients with thalamic stroke. Our novel findings have the potential to inform future targeted and individualized therapies. However, further comprehensive studies are necessary to validate our results.

Optical coherence tomography of the macular ganglion cell layer in children with neurofibromatosis type 1 is a useful tool in the assessment for optic pathway gliomas.

Optic pathway glioma (OPG) is a feared complication to neurofibromatosis type 1 (NF1) since it can cause visual impairment in young children. The main goal of screening is to detect symptomatic OPGs that require treatment. Optical coherence tomography (OCT) has been suggested as a tool for detection of neuro-retinal damage. To investigate whether the ganglion cell layer assessed by OCT is a reliable measure to identify and detect relapses of symptomatic OPGs in children with NF1. Children (3-6 years) with NF1, with and without known OPG and children with sporadic OPG (S-OPG) resident in the Stockholm area, were invited and followed in a prospective study during a three-year period. Brain magnetic resonance tomography (MRI) had been performed in children with symptoms of OPG. Outcome measures were VA in logMAR, visual field index (VFI), average thicknesses of the ganglion cell-inner plexiform layer (GC-IPL), and peripapillary retinal nerve fiber layer (pRNFL). There were 25 children with MRI-verified OPG and 52 with NF1 without symptomatic OPG. Eyes from NF1 patients without symptoms of OPG showed significantly better results in all four analyzed parameters compared to eyes with NF1-associated OPG. Mean GC-IPL measurements seemed stable and reliable, significantly correlated to pRNFL (correlation coefficient (r) = 0.662, confidence interval (CI) = .507 to .773 p<0.001), VA (r = -0.661, CI = -7.45 to -.551, p<0.001) and VFI (r = 0.644, CI = .452 to .774, p<0.001). GC-IPL measurements were easy to obtain and acquired at considerably younger age than pRNFL (5.6±1.5 vs 6.8±1.3; p<0.001). The mean GC-IPL thickness could distinguish well between eyes with OPG and eyes without symptomatic OPG in children with NF1. As thinning of GC-IPL assessed with OCT could indicate underlying OPG, it should be included in the screening protocol of children with questionable VA measurements and in particular in children with NF1.

Dyslipidemia and reduced retinal layer thicknesses in mild to moderate non-proliferative diabetic retinopathy.

To investigate the changes in ganglion cell layer-inner plexiform layer (GCL-IPL) thickness and its association with peripheral blood indices in non-proliferative diabetic retinopathy (NPDR). In this cross-sectional study, 132 participants were categorized into three groups: 30 healthy volunteers (control group), 50 diabetic patients with non-diabetic retinopathy (NDR group), and 52 patients with NPDR. Optical coherence tomography (OCT) was used to measure the retinal nerve fiber layer (RNFL) and GCL-IPL thicknesses in the macula. The associations between RNFL loss and systemic risk factors for DR, such as diabetes duration, triglyceride (TG), total cholesterol (TC), high-density lipoprotein (HDL), low-density lipoprotein (LDL), and hemoglobin A1c (HbA1c) were evaluated. The average, superior, and nasal thicknesses in the NDR and NPDR groups were significantly thinner compared to the control group (P=0.002, 0.020, 0.090, respectively). Similarly, GCL-IPL thicknesses in the 3 mm and 6 mm zones of the NDR and NPDR groups were thinner than those in the control group (P=0.040, 0.022, 0.037, respectively). Temporal thicknesses in the 3 mm range of the NDR and NPDR groups were also thinner than in the control group (P=0.010). Superior RNFL thickness was positively correlated with HbA1c (r=0.200, P=0.044), and negatively correlated with HDL (r=-0.198, P=0.047). The average inferior and nasal GCL-IPL thicknesses were negatively correlated with TC across the 3 mm zone (r=-0.211, P=0.033; r=-0.224, P=0.023; r=-0.227, P=0.022). Additionally, the average thickness of GCL-IPL in the 6-mm range were positively correlated with the duration of diabetes (r=0.196, P=0.048). This study demonstrates that dyslipidemia in diabetic patients correlates with reductions in RNFL and GCL-IPL thicknesses, suggesting a role in the pathogenesis of diabetic retinopathy.

Interocular Symmetry and Intermachine Reproducibility of Optic Disc and Macular Parameters Measured by Two Different Models of Optical Coherence Tomography.

To compare the interocular symmetry and investigate the intermachine reproducibility of optic disc and macular data measured by spectral-domain high-definition optical coherence tomography (HD-OCT) Cirrus HD-OCT 4000 and HD-OCT 5000 from healthy subjects. Forty-three volunteers were examined with both HD-OCT 4000 and HD-OCT 5000 at the same visit. Optic nerve head (ONH) and macular data were acquired using ONH Cube 200×200 scans and macular volume cube 512×128 scans, respectively. The average age of the participants was 33 ± 8.6 years. Interocular OCT parameters of ONH and macula showed a high correlation between the right and left eyes regardless of HD-OCT models, displaying a low coefficient of variation (CV). However, the average retinal nerve fiber layer (RNFL) was thicker (96.67±11.19µm vs 95.3±10.89µm, p<0.01), and the average central subfield thickness (261.51±17.45µm vs 262.51±17.39 µm, p<0.01) and cube average thickness (283.91± 13.59µm vs 286.55±13.09µm, p<0.05) were thinner when measured by Cirrus 4000 compared to 5000. Intermachine reproducibility and reliability of RNFL and macular parameters exhibited a high intraclass correlation coefficient (ICC) (0.985) and low CV (2.4%). Ganglion cell-inner plexiform layer (GCIPL) measured by two OCT models showed similar values with an average thickness of 85 µm and had high intermachine reproducibility with high ICC (0.993) and low CV (1.2%). High interocular symmetry was observed across both HD-OCT models. Intermachine reproducibility for RNFL and all macular parameters was also high. GCIPL showed minimal intermachine differences with high reproducibility and reliability. Thus, the results imply that GCIPL values measured by two Cirrus OCT models may be used interchangeably.

Comparison of ocular changes in multiple sclerosis and neuromyelitis optica spectrum disorder patients.

To explore ocular changes in patients with MS and NMOSD via SD-OCT and PVEP analysis. From August 2020 to July 2021, 82 patients (164 eyes) diagnosed with MS, 59 patients (118 eyes) diagnosed with NMOSD and 50 healthy controls (100 eyes) were retrospectively selected. SD-OCT and PVEP were performed to compare retinal nerve fibre layer (RNFL) thickness around the optic disc, ganglion cell inner plexiform layer (GCIPL) thickness in the macula and P100 latency and amplitude between the disease groups and the control group. In the NMOSD and MS groups, the thickness of the GCIPL quadrants in eyes with optic neuritis was thinner than that in eyes without optic neuritis, and the amplitude of the P100 wave decreased. In addition, in eyes with optic neuritis, patients with NMOSD have thinner RNFL thicknesses in the temporal and superior quadrants than patients with MS, and the thickness of the GCIPL is thinner in each region. In eyes without optic neuritis, patients with MS have thinner nasal RNFL than do those with NMOSD. SD-OCT and VEP may be useful for monitoring and distinguishing pathological changes in MS and NMOSD patients.

Exploring Vitreous Haze as a Potential Biomarker for Accelerated Glymphatic Outflow and Neurodegeneration in Multiple Sclerosis: A Cross-Sectional Study.

The glymphatic system removes neurodegenerative debris. The ocular glymphatic outflow is from the eye to the proximal optic nerve. In multiple sclerosis (MS), atrophy of the optic nerve increases the glymphatic outflow space. Here, we tested whether vitreous haze (VH) can provide novel insights into the relationship between neurodegeneration and the ocular glymphatic system in MS. This cross-sectional study comprised 315 persons with MS and 87 healthy controls (HCs). VH was quantified from optical coherence tomography (OCT) volume scans. Neurodegeneration was determined on three-dimensional T1 (3DT1) MRI, lesion detection on fluid-attenuated inversion (FLAIR), and layer thickness on OCT. Generalized estimating equations, corrected for age, were used to analyze associations between VH and metrics for neurodegeneration, demographics, and clinical scales. Group differences were determined between mild, moderate, and severe disability. On the group level, VH scores were comparable between MS and control (p = 0.629). In MS, VH scores declined with disease duration (β = -0.009, p = 0.004) and age (β = -0.007, p = 0.001). There was no relation between VH scores and higher age in HCs. In MS patients, VH was related to normalized gray (NGMV, β = 0.001, p = 0.011) and white matter volume (NWMV, β = 0.001, p = 0.003), macular ganglion cell-inner plexiform layer thickness (mGCIPL, β = 0.006, p < 0.001), and peripapillary retinal nerve fiber layer thickness (pRNFL, β = 0.004, p = 0.008). VH was significantly lower in severe compared to mild disability (mean difference -28.86%, p = 0.058). There is a correlation between VH on OCT and disease duration, more severe disability and lower brain volumes in MS. Biologically, these relationships suggest accelerated glymphatic clearance with disease-related atrophy.

Factors Contributing to the Development of Choroidal Microvasculature Dropout in Glaucoma Suspects and Patients with Glaucoma.

We aimed to characterize and compare the occurrence of peripapillary microvasculature dropout (MvD) between glaucoma suspects and patients with glaucoma. In addition, the factors related to the development of parapapillary MvD in glaucoma suspects and patients with glaucoma were investigated. Of a total 150 eyes, 68 eyes of glaucoma suspects and 82 eyes of glaucoma patients were analyzed in this study. Univariate and multivariate logistic regression analyses were used to identify factors associated with MvD development. The classification of glaucoma patients or glaucoma suspects was not significantly associated with MvD development (beta 1.368, 95% CI, 0.718-2.608, p = 0.341). In the regression analysis of the glaucoma suspect group, greater axial length (beta 1.520, 95% CI, 1.008-2.291, p = 0.046) and baseline cup volume (beta 3.993, 95% CI, 1.292-12.345, p = 0.035) among the baseline factors and the slope of ganglion cell-inner plexiform layer (GCIPL) thickness (beta 0.027, 95% CI, 0.072-0.851, p = 0.027) and central visual field (VF) progression (beta 7.040, 95% CI, 1.781-16.306, p = 0.014) among follow-up factors were significantly associated with MvD development. In the glaucoma group, central VF progression (beta 5.985, 95% CI, 1.474-24.083, p = 0.012) and ONH depression (beta 3.765, 95% CI, 1.301-10.895, p = 0.014) among follow-up elements were observed as significant factors and the baseline factor had little relationship. MvD appears not only as a result of the progression of axonal loss of RGC in glaucoma but may also be developed due to structural changes and mechanical susceptibility of the ONH associated with baseline characteristics. Analyzing the structural susceptibility of the ONH can predict the occurrence of MvD, which can be helpful in predicting the progression of glaucoma.

Comparison of Patterns of Structural Progression in Primary Open Angle Glaucoma and Pseudoexfoliation Glaucoma.

Primary open angle glaucoma and pseudoexfoliation glaucoma showed different progression patterns of the retinal nerve fiber layer and ganglion cell-inner plexiform layer thinning in OCT-guided progression analysis. To compare the patterns of progression of retinal nerve fiber layer (RNFL) and macular ganglion cell-inner plexiform layer (GCIPL) thinning by guided progression analysis (GPA) of optical coherence tomography (OCT) in primary open angle glaucoma (POAG) and pseudoexfoliation glaucoma (PXG). The progression of RNFL and GCIPL thinning was assessed by the GPA of Cirrus HD-OCT (Carl Zeiss Meditec, Dublin, CA). By overlaying the acquired images of the RNFL and GCIPL thickness-change maps, the topographic patterns of progressive RNFL and GCIPL thinning were evaluated. The rates of progression of RNFL and GCIPL thinning were analyzed and compared between patients with POAG and those with PXG. Of the 248 eyes of 248 patients with POAG (175 eyes of 175 patients) or PXG (73 eyes of 73 patients) enrolled, 156 POAG eyes and 48 PXG eyes were included. Progressive RNFL thinning was significantly more common in PXG than in POAG ( P =0.005). According to the RNFL progression-frequency maps, progression appeared mainly in the superotemporal and inferotemporal areas in POAG, whereas it had invaded more into the temporal area in PXG. According to the GCIPL maps, progression was most common in the inferotemporal area in both POAG and PXG. The average progression rate of GCIPL thinning was faster in PXG than in POAG ( P =0.013), and when analyzed in 2 halves (superior/inferior), the progression rate of the inferior half was faster in PXG than in POAG ( P =0.011). OCT GPA showed progression patterns of RNFL and GCIPL thinning in POAG and PXG. Understanding the specific patterns of progressive RNFL and GCIPL thinning according to glaucoma type may prove helpful to glaucoma-patient treatment and monitoring.

Diagnostic performance of wide-field optical coherence tomography angiography in detecting open-angle glaucoma in high myopia.

To compare the diagnostic performance of the capillary density (CD) of the central 1-6 mm and peripheral 6-12 mm annular regions in detecting open-angle glaucoma in high myopia (HM) using 15 × 12 mm wide-field swept-source optical coherence tomography angiography (WF SS-OCTA). The study enrolled 206 and 103 eyes with HM and highly myopic open-angle glaucoma (HM-OAG), respectively. WF SS-OCTA images centred on the fovea were obtained to analyse the changes in the CD in the 1-3 mm, 3-6 mm, 6-9 mm, and 9-12 mm annular regions. CD of the superficial capillary plexus (SCP) was measured with the built-in software. The area under the receiver operating characteristic curve (AUROC) of each region was compared. The diagnostic performance of the SCP CD in the central 1-6 mm annular region (AUROC = 0.849) was better than that in the peripheral 6-12 mm annular region (AUROC = 0.756, p = 0.001). The annular AUROCs of SCP CD peaked in the 3-6 mm annular region (AUROC = 0.858) and gradually decreased with increasing diameter and were lower than the corresponding AUROCs of the ganglion cell-inner plexiform layer thickness (p < 0.05 for all comparisons). SCP CD of the inferior quadrant in the 3-6 mm annular region had the best diagnostic performance (AUROC = 0.859). The SCP CD in the central 1-6 mm annular region exhibited better diagnostic performance for the detection of HM-OAG in HM. The assessment of more peripheral regions has no added value in detecting glaucoma in HM.

Topographic comparison of the retinal microvascular changes between patients with compressive and glaucomatous optic neuropathies

We investigated the difference in optical coherence tomography angiography characteristics between the patients with compressive optic neuropathy (CON, n = 26) and glaucomatous optic neuropathy (GON, n = 26), who were matched for the severity of visual field defect. The peripapillary retinal nerve fiber layer (pRNFL) thickness in the nasal and temporal sectors was thinner in the CON group, whereas the inferior pRNFL thickness was thinner in the GON group. Accordingly, the CON group had lower peripapillary vessel density (pVD) in the nasal and temporal sectors, and the GON group in the inferior sector. In the macular area, the CON group had a thinner macular ganglion cell-inner plexiform layer in the superior and nasal sectors, whereas the GON group in the inferior sector. However, the CON group did not have a lower macular VD than the GON group in any sector, whereas the GON group exhibited lower superficial capillary plexus VD in the superior, inferior, and temporal sectors. Comparison of the structure–vasculature correlation revealed a significant difference in the nasal and temporal peripapillary areas and superior and nasal macular sectors; a decrease in VD was greater in the GON group than in the CON group when the comparable structural change occurred.

Effect of pan retinal photocoagulation on macular ganglion cell - inner plexiform layer and peripapillary retinal nerve fibre layer thickness

: To determine the effect of pan retinal photocoagulation (PRP) on spectral domain optical coherence tomography (SD OCT) morphologic parameters like macular ganglion cell-inner plexiform layer (GCIPL), peripapillary retinal nerve fibre layer (RNFL) thickness and central macular thickness (CMT) in diabetic retinopathy cases. This is a retrospective study including 52 eyes with severe non-proliferative to proliferative diabetic retinopathy without macular oedema who required PRP. Macular GCIPL, CMT and peripapillary RNFL thickness measured at baseline and at 1-, 6-, 12- and 18-months post PRP with SD OCT. CMT, Macular GCIPL and peripapillary RNFL thickness increased significantly at 1 month (p&amp;#60;0.05), thereafter a decreasing trend noted at 6, 12 and 18 months. At 18 month CMT, GCIPL and RNFL thickness are higher than baseline but not statistically significant except temporal RNFL and Average GCIPL (p&amp;#60;0.05). A significant correlation found between changes in temporal RNFL and average GCIPL thickness (Pearson Correlation coefficient r= 0.652, 0.557, 0.782, 0.624 at 1, 6, 12 and 18 months respectively. P&amp;#60;0.05 for all values) CMT, macular GCIPL and peripapillary RNFL thickness increase following PRP; peaking at month 1 and stabilizing through next 18 months. Macular GCIPL thickness could be a reproducible indicator of temporal RNFL.

Correlation of contrast sensitivity with ganglion cell/inner plexiform layer thickness and damage location in glaucoma with varying severity.

To investigate the correlation of contrast sensitivity with macular region ganglion cell/inner plexiform layer (GC/IPL) thickness and damage location in open-angle glaucoma (OAG) of varying severity. Cross-sectional study with 106 patients (203 eyes) who had OAG. Contrast sensitivity of each eye evaluated by quick contrast sensitivity function test based on intelligent algorithm. The GC/IPL thickness measured with optical coherence tomography; six sectors were delineated for localization of damage area. All eyes were grouped by the healthy macular sector and divided into pre-perimetric, early, moderate, and advanced stages, according to severity of visual field impairment. Mean GC/IPL thickness in the entire macular region and each sector were correlated with parameters that reflected contrast sensitivity (p < 0.01). The structure-function correlations were stronger nasally compared with temporally, and superiorly compared with inferiorly. Eyes with normal structure in inferior temporal sector had less visual field (p' = 0.024) and macular damage (p' = 0.034) compared with eyes that had healthy superior nasal sector; there was no difference in contrast sensitivity (p = 0.898). The structure-function correlations were significant in early, moderate, and advanced glaucoma (p < 0.05) but not in pre-perimetric glaucoma (p = 0.116). GC/IPL thinning in all sectors of the macular region in OAG was correlated with contrast sensitivity impairment, whereas the inferior temporal sector was least affected. Contrast sensitivity was supported as a severity evaluation indicator of early, moderate, and advanced glaucoma, but not of pre-perimetric glaucoma.

Evaluation of ganglion cell-inner plexiform layer thickness in the diagnosis of pre-perimetric glaucoma and comparison to retinal nerve fiber layers.

Evaluation of ganglion cell-inner plexiform layer thickness in the diagnosis of pre-perimetric glaucoma (PPG) and comparison to retinal nerve fiber layers. This study was a prospective hospital-based study. A total of 30 PPG and control patients were studied for retinal nerve fiber layer thickness (RNFL) and ganglion cell-inner plexiform layer complex (GC-IPL) by spectral-domain optical coherence tomography. PPG was defined as eyes with a normal visual field and one or more localized RNFL defects that were associated with a typical glaucomatous disc appearance. Diagnostic abilities of GC-IPL, optic nerve head (ONH), and RNFL parameters were computed using area under receiver-operating curve (AUROC), sensitivity, and specificity. GC-IPL parameters showed significant changes in PPG cases as compared to normal subjects in each region ( P value < 0.001). RNFL parameters also differed significantly from normal subjects in all quadrants ( P value 0.003 to < 0.001). Within GC-IPL parameters, the superotemporal region had the maximum area under the curve (AUC), followed by inferior, superior, and inferotemporal regions. Within RNFL parameters, the inferior quadrant had the maximum AUC, followed by superior and nasal quadrants. the GC-IPL parameters in PPG showed that the AUC of the GC-IPL parameters was much higher than those of the ONH and RNFL values. Although both the parameters RNFL and GC-IPL showed significant changes in PPG patients compared to healthy subjects, a higher AUC of GC-IPL points toward the higher sensitivity of GC-IPL than RNFL for detecting glaucoma in early stages.

Effect of ERM on RNFL, GCIPL and Macular Thickness According to the Severity of Glaucoma

Purpose: To investigate the effect of an epiretinal membrane (ERM) on peripapillary retinal nerve fiber layer thickness (pRNFLT), macular ganglion cell-inner plexiform layer thickness (mGCIPLT) and macular thickness (MT) in relation to glaucoma severity using swept-source optical coherence tomography (SS-OCT).Methods: In total, 105 eyes of 105 glaucoma patients with ERM were matched at a 1:1 ratio with glaucoma patients without ERM according to age, sex, cataract surgery, axial length and mean deviation based on visual field tests. The differences in pRNFLT, mGCIPLT and MT between the two groups were assessed using SS-OCT. Furthermore, the patients were divided into three glaucoma-severity groups, and the differences in pRNFLT, mGCIPLT and MT were compared between glaucoma patients with and without ERM in each group.Results: In all patients, including those with early, moderate, and advanced glaucoma, those with ERM had greater average, temporal quadrant, and 7, 8, 9, 10, and 11 o’clock pRNFLT values compared to those without ERM. Additionally, mGCIPLT and MT were thicker in glaucoma patients with ERM in all groups. The difference in pRNFLT at the 7 and 11 o’clock positions between glaucoma patients with and without ERM was significantly more pronounced in the moderate glaucoma group than in the early glaucoma group (&lt;i&gt;p&lt;/i&gt; = 0.043 and &lt;i&gt;p&lt;/i&gt; = 0.012, respectively).Conclusions: ERM has notable effects on the pRNFLT, mGCIPLT and MT. Furthermore, the magnitude of its effect on pRNFLT varies with glaucoma severity.

Structural changes in the retina and serum HMGB1 levels are associated with decreased cognitive function in patients with Parkinson's disease

BackgroundCognitive impairment is a serious nonmotor symptom in patients with Parkinson's disease (PD). Currently, there are few studies investigating the relationship of serum markers and retinal structural changes with cognitive function in PD. ObjectiveTo investigate the relationship between retinal structural changes, serum high mobility group box-1 (HMGB1) levels and cognitive function and motor symptoms in PD patients. MethodsEighty-nine participants, including 47 PD patients and 42 healthy subjects, were enrolled. PD patients were divided into Parkinson's disease with normal cognitive (PD-NC), Parkinson's disease with mild cognitive impairment (PD-MCI), and Parkinson's disease with dementia (PDD) groups. The motor and nonmotor symptoms of PD patients were evaluated with clinical scale. Serum HMGB1 levels were detected by enzyme-linked immunosorbent assay (ELISA), and ganglion cell-inner plexiform layer complex (GCIPL) thickness changes in the macula were quantitatively analyzed by swept source optical coherence tomography (SS-OCT) in all patients. ResultsCompared with the control group, the macular GCIPL (t = −2.308, P = 0.023) was thinner and serum HMGB1 (z = −2.285, P = 0.022) was increased in PD patients. Macular GCIPL thickness in patients with PD-MCI and PDD were significantly lower than that in PD-NC patients, but there were no significant difference between the PD-MCI and PDD groups. Serum HMGB1 levels in patients with PD-MCI and PDD were significantly higher than those in PD-NC patients, and serum HMGB1 levels in PDD patients were higher than those in PD-MCI patients. Correlation analysis showed that serum HMGB1 levels in PD patients were positively correlated with disease duration, HY stage, UPDRS-I score, UPDRS-III score, and UPDRS total score and negatively correlated with MOCA score. Macular GCIPL thickness was negatively correlated with HY stage and positively correlated with MOCA score, and macular GCIPL thickness was negatively correlated with serum HMGB1 level. Logistic regression analysis showed that elevated serum HMGB1 level, thinner macular GCIPL thickness, and higher HY stage were independent risk factors for Parkinson's disease with cognitive impairment (PD-CI). The areas under the receiver operating characteristic curve (AUC) for the serum HMGB1 level and macular GCIPL thickness-based diagnosis of PD-MCI, PDD and PD-CI based on in patients with PD were 0.786 and 0.825, 0.915 and 0.856, 0.852 and 0.841, respectively. The AUC for the diagnosis of PD-MCI, PDD and PD-CI with serum HMGB1 level and GCIPL thickness combined were 0.869, 0.967 and 0.916, respectively. ConclusionThe macular GCIPL thickness and serum HMGB1 level are potential markers of cognitive impairment in PD patients, and their combination can significantly improve the accuracy of the diagnosis of cognitive impairment in PD.

Mendelian randomization reveals association between retinal thickness and non-motor symptoms of Parkinson’s disease

Retinal thickness is related to Parkinson’s disease (PD), but its association with the severity of PD is still unclear. We conducted a Mendelian randomized (MR) study to explore the association between retinal thickness and PD. For the two-sample MR analysis, the summary statistics obtained from genome-wide association studies on the thickness of Retinal nerve fiber layer (RNFL) and ganglion cell inner plexiform layer (GCIPL) were employed as exposure, while the summary statistics associated with PD were used as the outcome. The primary approach utilized was inverse variance weighted. To correct for multiple testing, the false discovery rate (FDR) was employed. For sensitivity analysis, an array of robust MR methods was utilized. We found genetically predicted significant association between reduced RNFL thickness and a reduced risk of constipation in PD (odds ratio [OR] = 0.854, 95% confidence interval [CI] (0.782, 0.933), P < 0.001, FDR-corrected P = 0.018). Genetically predicted reduced RNFL thickness was associated with a reduced Unified Parkinson’s Disease Rating Scale total score (β = −0.042, 95% CI (−0.079, 0.005), P = 0.025), and reduced GCIPL thickness was associated with a lower risk of constipation (OR = 0.901, 95% CI (0.821, 0.988), P = 0.027) but a higher risk of depression (OR = 1.103, 95% CI (1.016, 1.198), P = 0.020), insomnia (OR = 1.090, 95% CI (1.013, 1.172), P = 0.021), and rapid eye movement sleep behaviour disorder (RBD) (OR = 1.198, 95% CI (1.061, 1.352), P = 0.003). In conclusion, we identify an association between retinal thickness and non-motor symptoms (constipation, depression, insomnia and RBD) in PD, highlighting the potential of retinal thickness as a biomarker for PD nonmotor symptoms.

Characterization of retinal microvasculature and structure in atrial fibrillation.

Quantitative changes in retinal microvasculature are associated with subclinical cardiac alterations and clinical cardiovascular diseases (i.e., heart failure and coronary artery disease). Nonetheless, very little is known about the retinal vascular and structural changes in patients with atrial fibrillation (AF). Our study aims to characterize the microvasculature and structure of the retina in AF patients and explore their differences in different types of AF (paroxysmal and sustained AF). This cross-sectional study was conducted at the Departments of Neurology and Cardiology in West China Hospital, Chengdu, China. Individuals aged 40 years or older with a diagnosis of AF were eligible for inclusion and underwent an evaluation and diagnosis confirmation before enrollment. Control individuals aged 40 years or older and without a history of AF, ocular abnormalities/disease, or any significant systemic illness were recruited. The retinal vascular and structural parameters were assessed using swept-source optical coherence tomography (SS-OCT)/SS-OCT angiography. Echocardiographic data of left atrium (LA) diameter were collected in patients with AF at the time of inclusion. A total of 242 eyes of 125 participants [71 men (56.8%); mean (SD) age, 61.98 (8.73) years] with AF and 219 eyes of 111 control participants [53 men (47.7%); mean (SD) age, 62.31 (6.47) years] were analyzed. In our AF cohort, 71 patients with paroxysmal AF and 54 patients with sustained AF (i.e., persistent/permanent AF) were included. Decreased retinal microvascular perfusion (β coefficient = -0.08; 95% CI, -0.14 to -0.03) and densities (β coefficient = -1.86; 95% CI, -3.11 to -0.60) in superficial vascular plexus (SVC) were found in the eyes of the participants with AF. In regard to retinal structures, thinner ganglion cell-inner plexiform layer (GCIPL; β coefficient = -2.34; 95% CI, -4.32 to -0.36) and retinal nerve fiber layer (RNFL) thicknesses (β coefficient = -0.63; 95% CI, -2.09 to -0.18) were observed in the eyes of the participants with AF. The retinal parameters did not significantly differ between paroxysmal and sustained AF (all P > 0.05). However, significant interactions were observed between LA diameter and AF subtypes with the perfusion and densities in SVC (P < 0.05). This study found that individuals with AF had decreased retinal vascular densities and perfusion in SVC, as well as thinner GCIPL and RNFL thickness compared with age- and sex-matched control participants. The differences of the retinal microvasculature in SVC between paroxysmal and sustained AF depend on the LA diameter. Given our findings, further longitudinal studies with our participants are of interest to investigate the natural history of retinal microvascular and structural changes in individuals across the clinical process of AF and AF subtypes.

The Relationship Between Inner Retinal Thickness, Cognition, and Frailty in Community‐dwelling Older Adults: findings from a 6‐year follow‐up study

AbstractBackgroundThinning of the inner retinal thickness, including ganglion cell‐inner plexiform layer (GC‐IPL) and retinal nerve fiber layer (RNFL), has been related to cognitive decline. However, the relationship between GC‐IPL/RNFL thickness, physical frailty, and cognitive frailty remains unclear. Therefore, this longitudinal study aims to investigate the association of these retinal markers with cognition, frailty, and cognitive frailty.MethodThis is a 7‐year cohort study including 221 community‐dwelling elders in the ongoing Taiwan Initiate for Geriatric Epidemiological Research (TIGER) between 2015 and 2017 and received biennial assessments for cognition and physical frailty three consecutive times. The global and domain‐specific (memory, attention, executive function, and language) cognition were assessed using the Taiwanese version of the Montreal Cognitive Assessment and a series of neuropsychological tests. Physical frailty was assessed by modified Fried frailty phenotypes. The generalized linear mixed model was used to analyze the association between GC‐IPL/RNFL thickness and global/domain‐specific cognitive frailty adjusted for age, sex, years of education, apolipoprotein E ε4 status carriers, cigarette smoking status, presence of depressive symptoms, hypertension or diabetes mellitus, years of follow‐up, and practice effect.ResultThe performance of global cognition decreased as the mean GC‐IPL thickness of bilateral eyes deviated from the sample mean (76.6 µm) (quadratic GC‐IPL: β = ‐0.4×10−2; 95% confidence interval: ‐0.7×10−2 to ‐0.2×10−2). Similar associations were also found for logical memory with RNFL/GC‐IPL thickness. No significant association was observed between RNFL/GC‐IPL thickness and physical frailty. An increased odds of impaired logical memory‐physical frailty was found for GC‐IPL (quadratic GC‐IPL: adjusted odds ratio = 1.005; 95% confidence interval: 1.001 to 1.005), but no significant association was found between cognitive frailty and RNFL thickness.ConclusionChange in the GC‐IPL thickness was associated with impaired cognition and poor logical memory‐frailty performance. The inner retinal thickness may serve as a biomarker for cognition or cognitive frailty in non‐demented elders.