Retinal Ganglion Cell Layer Thickness Research Articles

Impact of intravitreal ranibizumab, aflibercept and bevacizumab on retinal ganglion cell and nerve fibre layer thickness in Neovascular age-related macular degeneration.

To compare the effects of monotherapy with intravitreal ranibizumab, aflibercept and bevacizumab on retinal ganglion cell layer (RGCL) and retinal nerve fibre layer (RNFL) in patients with naïve neovascular age-related macular degeneration (nAMD). This is a retrospective cohort study with three-groups comparison. 83 patients and 97 eyes on continuous monotherapy with an intravitreal anti-vascular endothelial growth factor (anti-VEGF) were followed for 24 months and divided into three groups according to anti-VEGF (aflibercept: 25 eyes, ranibizumab: 34 eyes, bevacizumab: 38 eyes). Main outcome measures included: RGCL and RNFL thickness, best corrected visual acuity (BCVA), central macular thickness (CMT), macular volume (MV) and the presence of intraretinal fluids (IRF), subretinal fluids (SRF) and retinal pigment epithelial atrophy (RPE-atrophy). All outcome measures were recorded at the time of the first injection, 1 and 2 years after treatment and compared longitudinally and between groups. The mean age was 79 ± 7 years. The RGCL thickness, MV, CMT and the presence of IRF and SRF decreased significantly within all three medication groups (p < 0.05 for all) with no significant difference between groups over the 2-year follow-up period (p > 0.10 for all). The decrease in RNFL thickness was not significant within or between the groups after a 2-year follow-up (p > 0.055 for all). RPE-atrophy increased significantly after 2 years in all three groups (p < 0.028 for all) with no significant difference between groups at all three time points (p > 0.307 for all). BCVA was comparable between the three groups over the 2-year follow-up period (p > 0.22 for all). Monotherapy with intravitreal aflibercept, bevacizumab and ranibizumab was associated with comparable significant decreases in RGCL thickness, CMT, MV, IRF and SRF in naïve nAMD patients during the first 2 years of treatment. Furthermore, no significant differences either in BCVA or RNFL thickness were observed between the three intravitreal anti-VEFGs during the first 2 years of treatment.

Treatment of nonarteritic anterior ischemic optic neuropathy with an endothelin antagonist: ENDOTHELION (ENDOTHELin antagonist receptor in Ischemic Optic Neuropathy)—a multicentre randomised controlled trial protocol

BackgroundNonarteritic anterior ischemic optic neuropathy (NAAION) is a major cause of blindness in individuals over 50 years of age, with no available effective treatment. The oral dual endothelin receptor antagonist, bosentan, increases retinal optic nerve head blood flow in healthy humans and glaucoma patients. The objective of this trial is to assess the efficacy of bosentan administered at the acute stage in improving outcomes in NAAION patients.MethodsENDOTHELION (ENDOTHELin antagonist receptor in Ischemic Optic Neuropathy) is a phase III, interventional, prospective, multicentre, placebo-controlled randomised double-blind clinical trial. The primary outcome is change in the visual field mean deviation (MD) at 3 months (Humphrey 30-2 SITA standard programme). Secondary outcomes include MD and visual acuity changes up to 24 months, changes in peripapillary retinal nerve fibre and macular ganglion cell layer thickness in the affected eye, as measured by optical coherence tomography, rate of NAAION bilateralisation at 2 years, and quality-of-life. Patients over 50 years of age presenting with typical NAAION of recent onset (less than 21 days) are randomly assigned to either 125 mg oral bosentan or placebo, twice a day, during 8 weeks. Besides visits during the treatment phase, patients attend follow-up visits at 2, 3, 6, 12 and 24 months. The inclusion of patients began in August 2015 at five French University hospital ophthalmology departments and two specialised ophthalmology centres. It is planned to include 86 patients in this trial. To date we have included 72 patients and 49 have completed the full follow-up process.DiscussionAn endothelin receptor antagonist is a potential approach to improving the anatomical and functional prognosis of patients with NAAION. This multicentre double-blind randomised controlled trial is an opportunity to assess (1) the effect of bosentan on the structure and function of the optic nerve in NAAION, at 3 months, (2) the effect of bosentan on the bilateralisation rate at 24 months and (3) the tolerance profile of bosentan in this population.Trial registrationClinicalTrials.gov NCT02377271. Registered on March 3, 2015.

A study of retinal changes in women with polycystic ovarian syndrome.

To compare the optical coherence tomography (OCT)-based retinal nerve fiber layer (RNFL) and ganglion cell layer (GCL) thickness at the posterior pole, and total macular thickness of women with the polycystic ovarian syndrome (PCOS) versus healthy reproductive age group females. The study included 110 eyes of 55 diagnosed cases of PCOS (study group) and 110 eyes of 55 healthy reproductive age group (15-49 years) females (control group). All patients underwent a detailed ophthalmological evaluation followed by an OCT to measure their retinal thicknesses. The body mass index (BMI) of patients was noted and compared with the retinal thickness. Also, the lipid profile and serum testosterone levels of PCOS patients were recorded. The retinal thicknesses in the two study were similar and there was no statistically significant difference. However, on stratification with BMI, it was seen that in patients with BMI>30 kg/m2, the superior Retinal Nerve Fibre Layer (RNFL) was significantly thicker in the PCOS group as compared with the control group (P = 0.0006). The mean serum testosterone level in patients with PCOS was 141.3 ± 23.2. Also, 65.45% of patients had a serum testosterone level of more than 70 ng/dL. The mean HDL cholesterol in patients with PCOS was 38.1 ± 15.6. The mean LDL cholesterol in PCOS patients was 98.4 ± 21.7, and the mean total cholesterol in PCOS patients was 153.6 ± 27.3. Androgens have a trophic action on nerves, which could explain the increased RNFL thickness in these patients.

Mapping Retinal Abnormalities in Psychosis: Meta-analytical Evidence for Focal Peripapillary and Macular Reductions.

Several studies have suggested that the retina structure is affected in schizophrenia spectrum disorders (SSD). We aimed to investigate the location and size of the potential differences between patients and healthy controls (HC) in several thickness and volume measures across the retina. We included cross-sectional studies comparing peripapillary retinal nerve fiber layer (pRNFL) thickness, macular volume, macular thickness (MT), foveal thickness, ganglion cell and inner plexiform layer thickness (GCL+IPL), cup volume, and cup/disc ratio (C/D) in the right and/or left eyes and/or the pRNFL and MT quadrants between patients with SSD and HC. Search databases were MEDLINE, Web of Science, PsycINFO, Cochrane Central, and medrxiv.org. Risk of bias was assessed with the Newcastle-Ottawa Scale. Standardized mean differences (SMD), subgroup analysis, and meta-regression with several variables were computed using the dmetar package in R. PROSPERO: CRD42021287873. Data from 22 reports (942 patients, 742 HC) were included. We found a retinal thinning in pRNFL (-0.30; 95% CI: -0.46, -0.14), macula (-0.37; 95% CI: -0.61, -0.13), and GCL+IPL (-0.33; 95% CI: -0.57, -0.10). The retinal thinning was especially pronounced in the superior and inferior quadrants of the inner ring of the macula. We also observed a decrease of macular volume (-0.44; 95% CI: -0.68, -0.20) and an increase in C/D ratio (0.35; 95% CI: 0.03, 0.67). Current evidence demonstrates retinal thinning in SSD, affecting both axonal and cellular structures, specially focused in the inner ring of the macula.

Retinal ganglion cell layer thickness and volume measured by OCT changes with age, sex, and axial length in a healthy population

BackgroundThe ganglion cell layer (GCL) measurements with Optical Coherence Tomography (OCT) are important for both ophthalmologists and neurologists because of their association with many ophthalmic and neurological diseases. Different factors can affect these measurements, such as brain pathologies, ocular axial length (AL) as well as age and sex. Studies conducted to measure the GCL have overlooked many of these factors. The purpose of this study is to examine the effect of age, sex, and AL on normal retinal GCL thickness and volume in a healthy population without any neurological diseases.MethodsA prospective cross-sectional study was designed to measure GCL thickness and total volume with OCT with automated segmentation and manual correction where needed. Visual acuity, AL, and autorefraction were also measured. A mixed linear model was used to determine the association of the effect of the various parameters on the GCL thickness and volume.ResultsOne hundred and sixteen eyes of 60 subjects (12–76 years of age, 55% female) were examined of which 77% had 0 ± 2 D of spherical equivalent, and mean axial length was 23.86 mm. About 25% of the OCT-automated GCL measurements required manual correction. GCL thickness did not differ in similar anatomic regions in right and left eyes (P > 0.05). GCL volume was greater in males relative to females after adjustment for age and axial length (1.13 ± 0.07 mm3 for males vs 1.09 ± 0.09 mm3 for females; P = 0.031). GCL thickness differed between males and females in the inner retinal ring (P = 0.025) but not in the outer ring (P = 0.66). GCL volume declined with age (P = 0.031) but not after adjustment for sex and axial length (P = 0.138). GCL volume declined with longer axial length after adjustment for age and sex (P = 0.048).ConclusionAge, sex and axial length should be taken into consideration when measuring the GCL thickness and volume with OCT. Automated OCT segmentation should be reviewed for manual adjustments.

Myopia Alters the Structural Organization of the Retinal Vasculature, GFAP-Positive Glia, and Ganglion Cell Layer Thickness.

To describe the effect of myopic eye growth on the structure and distribution of astrocytes, vasculature, and retinal nerve fiber layer thickness, which are critical for inner retinal tissue homeostasis and survival. Astrocyte and capillary distribution, retinal nerve fiber (RNFL), and ganglion cell layer (GCL) thicknesses were assessed using immunochemistry and spectral domain optical coherence tomography on eleven retinas of juvenile common marmosets (Callithrix Jacchus), six of which were induced with lens-induced myopia (refraction, Rx: −7.01 ± 1.8D). Five untreated age-matched juvenile marmoset retinas were used as controls (Rx: −0.74 ± 0.4D). Untreated marmoset eyes grew normally, their RNFL thickened and their astrocyte numbers were associated with RNFL thickness. Marmosets with induced myopia did not show this trend and, on the contrary, had reduced astrocyte numbers, increased GFAP-immunopositive staining, thinner RNFL, lower peripheral capillary branching, and increased numbers of string vessels. The myopic changes in retinal astrocytes, vasculature, and retinal nerve fiber layer thickness suggest a reorganization of the astrocyte and vascular templates during myopia development and progression. Whether these adaptations are beneficial or harmful to the retina remains to be investigated.

Evaluation of iris epithelial and stromal thickness in patients with migraine by using optical coherence tomography

Objective: The amount of light reaching to the retina is an important factor for photophobia formation. Therefore, investigation of iris thickness in patients with migraine can be valuable for revealing their susceptibility to photophobia. In this study, it was aimed to evaluate the iris epithelial and stromal thickness, retinal ganglion cell layer (RGCL) thickness, and retinal nerve fibre layer (RNFL) thickness of patients with migraine. Methods: Forty-nine migraine patients (Group 1) and 50 control participants (Group 2) were included into this study. For obtaining standard measure in all participants, the epithelial and stromal thickness of dilatory and sphincter iris muscle was measured from the equal distance to the pupillary margin by using anterior segment mode of optical coherence tomography (AS-OCT). Additionally, RNFL and RGCL thicknesses were measured by using posterior segment mode of OCT (PS-OCT). Results: The epithelial thickness of iris sphincter muscle and the epithelial thickness of iris dilatory muscle was found to be significantly higher in patients with migraine compared to control subjects (p&lt;0.001, p=0.001 respectively). Additionally the stromal thickness of both iris sphincter and iris dilatory muscle (p&lt;0.001, p&lt;0.001 respectively) as well as the total thickness of iris sphincter and iris dilatory muscle was significantly higher in patients with migraine than control subjects (p&lt;0.001, p=0.02 respectively). However, no significant difference was found between patients with migraine and control subjects in terms of RNFL and RGCL thicknesses (p=0.1 and p=0.7 respectively). Conclusion: The finding of high epithelial and stromal iris thickness in patients with migraine may support the possible role of increased pupillary dynamic in photophobia formation.

Relationship between Central Corneal Thickness, Intra-Ocular Pressure, Retinal Nerve Fiber Layer Thickness and Ganglion Cell Layer Thickness in Primary Open Angle Glaucoma

Relationship between Central Corneal Thickness, Intra-Ocular Pressure, Retinal Nerve Fiber Layer Thickness and Ganglion Cell Layer Thickness in Primary Open Angle Glaucoma

Optical coherence tomography and visual evoked potentials in evaluation of optic chiasm decompression

Chiasmal compression is a known cause of visual impairment, often leading to surgical decompression of the optic chiasm (OC). A prospective study was held at University Hospital in Hradec Králové to explore sensitivity of optical coherence tomography (OCT) and visual evoked potentials (VEPs) to OC compression and eventual changes after a decompression. 16 patients with OC compression, caused by different sellar pathologies, were included. The main inclusion criterion was the indication for decompressive surgery. Visual acuity (VA), visual field (VF), retinal nerve fibre layer (RNFL) and ganglion cell layer (GCL) thickness, and peak time and amplitude of pattern-reversal (P-VEPs) and motion-onset VEPs (M-VEPs) were measured pre- and postoperatively. The degree of OC compression was determined on preoperative magnetic resonance imaging. For M-VEPs, there was a significant postoperative shortening of the peak time (N160) (p < 0.05). P100 peak time and its amplitude did not change significantly. The M-VEPs N160 amplitude showed a close relationship to the VF improvement. Thinner preoperative RNFL does not present a statistically important limiting factor for better functional outcomes. The morphological status of the sellar region should be taken into consideration when one evaluates the chiasmal syndrome. M-VEPs enable detection of functional changes in the visual pathway better than P-VEPs.

Retinal nerve fibre layer and ganglion cell layer thickness changes following intravitreal aflibercept for age-related macular degeneration

Purpose To evaluate the effect of intravitreal aflibercept (IVA) injections on peripapillary retinal nerve fibre layer thickness (RNFLT) and macular ganglion cell layer thickness (GCLT) in neovascular age-related macular degeneration (nAMD) patients during a 1-year follow-up. Methods This is a prospective study including 34 patients who were treated with aflibercept for treatment-naive nAMD. Following a loading phase of 3-monthly aflibercept, re-injections were performed on a pro re nata regimen for 12 months. Best-corrected visual acuity, intraocular pressure, and spectral-domain-optical coherence tomography analysis were performed at baseline and 1 month, 3 months, 6 months, and 12 months following treatment. Peripapillary RNFLT and macular GCLT along with the central macular thickness (CMT) and subfoveal choroidal thickness (SFCT) were evaluated at each visit. Results Mean number of aflibercept injections was 6.0 ± 1.8. Significant thinning was observed at the central macular ganglion cell layer and at 1 mm superior, temporal, and nasal ganglion cell layer compared to baseline at 1-year (p < 0.05). No significant change of RNFLT was shown (p > 0.05). Mean CMT and SFCT were significantly reduced after IVA therapy (p < 0.05, for both). No correlation was found between injection number and GCLT change. Conclusions Intravitreal aflibercept caused significant ganglion cell layer thinning during a 1-year follow-up without any changes in RNFLT. Intravitreal aflibercept itself may have a chance to induce decreased GCLT in nAMD patients.

Patterns of white and gray structural abnormality associated with paediatric demyelinating disorders

The impact of multiple sclerosis (MS) and myelin oligodendrocyte glycoprotein (MOG) - associated disorders (MOGAD) on brain structure in youth remains poorly understood. Reductions in cortical mantle thickness on structural MRI and abnormal diffusion-based white matter metrics (e.g., diffusion tensor parameters) have been well documented in MS but not in MOGAD. Characterizing structural abnormalities found in children with these disorders can help clarify the differences and similarities in their impact on neuroanatomy. Importantly, while MS and MOGAD affect the entire CNS, the visual pathway is of particular interest in both groups, as most patients have evidence for clinical or subclinical involvement of the anterior visual pathway. Thus, the visual pathway is of key interest in analyses of structural abnormalities in these disorders and may distinguish MOGAD from MS patients.In this study we collected MRI data on 18 MS patients, 14 MOGAD patients and 26 age- and sex-matched typically developing children (TDC). Full-brain group differences in fixel diffusion measures (fibre-bundle populations) and cortical thickness measures were tested using age and sex as covariates. Visual pathway analysis was performed by extracting mean diffusion measures within lesion free optic radiations, cortical thickness within the visual cortex, and retinal nerve fibre layer (RNFL) and ganglion cell layer thickness measures from optical coherence tomography (OCT). Fixel based analysis (FBA) revealed MS patients have widespread abnormal white matter within the corticospinal tract, inferior longitudinal fasciculus, and optic radiations, while within MOGAD patients, non-lesional impact on white matter was found primarily in the right optic radiation. Cortical thickness measures were reduced predominately in the temporal and parietal lobes in MS patients and in frontal, cingulate and visual cortices in MOGAD patients. Additionally, our findings of associations between reduced RNFLT and axonal density in MOGAD and TORT in MS patients in the optic radiations imply widespread axonal and myelin damage in the visual pathway, respectively. Overall, our approach of combining FBA, cortical thickness and OCT measures has helped evaluate similarities and differences in brain structure in MS and MOGAD patients in comparison to TDC.

Retinal microvasculature and neurodegenerative changes in males vs females with Alzheimer’s disease: A case‐control study

AbstractBackgroundWomen comprise two‐thirds of people living with AD, regardless of age and ethnicity. Retinal imaging is being increasingly investigated as a potential non‐invasive method to understand neuropathological and microvascular changes in AD. The purpose of this study was to evaluate differences among males and females in the superficial capillary plexus (SCP) of the retinal microvasculature in patients with Alzheimer’s disease (AD) compared to age‐matched cognitively healthy controls.MethodProspective cross‐sectional study of participants ³50 years of age with a diagnosis of AD compared to cognitively healthy controls who underwent optical coherence tomography OCT angiography (OCTA). The foveal avascular zone area (FAZ) and vessel density (VD) and perfusion density (PD) in the 3 and 6‐mm circle and ring using EDTRS overlay were calculated.ResultTwo hundred and two eyes (101 cases, 101 controls) were included. No significant sex differences were found in the AD or control cohorts in regard to VD or PD. Central subfield thickness (CST) and FAZ area were not different between male and female AD. Among controls, males had a thicker CST (p &lt; 0.001) and smaller FAZ area (P=0.003). Retinal nerve fiber layer (p &gt; 0.05) and ganglion cell layer (p=0.054) thicknesses were similar among male AD, female AD, and controls.ConclusionThere may be a loss of the physiologic sex‐related differences in retinal structure and microvasculature in AD compared to controls. Further studies are needed to elucidate the pathophysiological basis for these findings.

Magnetic Resonance Imaging-Visible Perivascular Spaces in the Basal Ganglia Are Associated With the Diabetic Retinopathy Stage and Cognitive Decline in Patients With Type 2 Diabetes.

Purpose: The aim of this study was to evaluate whether perivascular space (PVS) severity and retinal ganglion cell layer (GCL) thickness differed based on the stage of diabetic retinopathy (DR) and the cognitive status in patients with DR.Methods: A total of 81 patients with DR (51 in the non-proliferative group and 30 in the proliferative group) were included in this retrospective, cross-sectional study. PVS severity was assessed in the basal ganglia (BG) and centrum semiovale using MRI. The total cerebral small vessel disease (SVD) score was determined based on the numbers of lacunes and microbleeds and the severity of white matter hyperintensity. Optical coherence tomography was used to measure foveal and perifoveal GCL thicknesses. Cerebral SVD markers and cognitive function were compared between the groups, and correlations between the BG-PVS severity and the Mini-Mental Status Examination (MMSE) scores and GCL parameters were evaluated.Results: Patients with proliferative DR had higher BG-PVS severity (P = 0.012), higher total cerebral SVD scores (P = 0.035), reduced GCL thicknesses in the inferior (P = 0.027), superior (P = 0.046), and temporal (P = 0.038) subfields compared to patients with non-proliferative DR. In addition, the BG-PVS severity was negatively correlated with the MMSE score (P = 0.007), and the GCL thickness was negatively correlated with the BG-PVS severity (P-values < 0.05 for inferior, superior, and temporal subfields).Conclusion: BG-PVS severity and retinal GCL thickness may represent novel imaging biomarkers reflecting the stage of DR and cognitive decline in diabetic patients. Furthermore, these results suggest a possible link between cerebral and retinal neurodegeneration at the clinical level.

Diagnostic accuracy of total macular and ganglion cell layer thickness in differentiating different stages of glaucoma: an SD-OCT study

Purpose: To determine the diagnostic accuracy of mean macular retinal thickness (mRT) and macular ganglion cell layer (mGCL) thickness measured by Spectralis spectral-domain optical coherence tomography (SD-OCT) posterior pole thickness map (PPTM) in differentiating between normal and glaucoma eyes of different severity.Study design: Cross-sectional study.Methods: All subjects were divided into normal and glaucoma groups according to the visual fields-based Glaucoma Staging System. They underwent slit-lamp examination, Humphrey visual field test, and SD-OCT (PPTM) imaging. mRT and mGCL thickness measurements were recorded. Analysis of variance with the least significant difference post hoc test was used for pairwise comparison. Ability to discriminate between normal eyes and those with differing severity of glaucoma was assessed using the area under the receiver operating characteristic curve (AUROC).Results: A total of 201 eyes from 201 subjects were enrolled in this study. The mean glaucoma was 290.2 ± 12.1 μm, 270.1 ± 17.0 μm, and 259.1 ± 15.0 μm, respectively. Mean mGCL thickness for the corresponding three groups was 32.3 ± 2.8 μm, 27.6 ± 3.3 μm and 22.2 ± 3.8μm, respectively. AUROC analysis showed excellent diagnostic discrimination between glaucoma and normal subjects for mRT (AUC: 0.90) and mGCL thickness (AUC: 0.92). The cut-off value of mRT was 274.9 μm (90% sensitivity, 75% specificity) and of mGCL thickness was 27.9 μm (93% sensitivity, 74% specificity). The discrimination ability performance of mRT and mGCL thickness deteriorated with increasing severity of glaucoma with mGCL thickness (AUC: 0.67–0.87) performing slightly better than mRT for all grades (AUC: 0.58–0.71).Conclusions: mRT and mGCL thickness measurement on PPTM showed great sensitivity and specificity to discern between normal and glaucomatous subjects. The discrimination ability of mRT and mGCL thickness, however, decreases with increasing grade of glaucoma. We believe SD-OCT PPTM offers an alternative imaging method to detect early glaucoma.

Age-related changes in the rhesus macaque eye

PurposeTo assess age-related changes in the rhesus macaque eye and evaluate them to corresponding human age-related eye disease. MethodsData from eye exams and imaging tests including intraocular pressure (IOP), lens thickness, axial length, and retinal optical coherence tomography (OCT) images were evaluated from 142 individuals and statistically analyzed for age-related changes. Quantitative autofluorescence (qAF) was measured as was the presence of macular lesions as related to age. ResultsAges of the 142 rhesus macaques ranged from 0.7 to 29 years (mean = 16.4 years, stdev = 7.5 years). Anterior segment measurements such as IOP, lens thickness, and axial length were acquired. Advanced retinal imaging in the form of optical coherence tomography and qAF were obtained. Quantitative assessments were made and variations by age groups were analyzed to compare with established age-related changes in human eyes. Quantitative analysis of data revealed age-related increase in intraocular pressure (0.165 mm Hg per increase in year of age), ocular biometry (lens thickness 7.2 μm per increase in year of age; and axial length 52.8 μm per increase in year of age), and presence of macular lesions. Age-related changes in thicknesses of retinal layers on OCT were observed and quantified, showing decreased thickness of the retinal ganglion cell layer and inner nuclear layer, and increased thickness of photoreceptor outer segment and choroidal layers. Age was correlated with increased qAF by 1.021 autofluorescence units per increase in year of age. ConclusionsThe rhesus macaque has age-related ocular changes similar to humans. IOP increases with age while retinal ganglion cell layer thickness decreases. Macular lesions develop in some aged animals. Our findings support the concept that rhesus macaques may be useful for the study of important age-related diseases such as glaucoma, macular diseases, and cone disorders, and for development of therapies for these diseases.

Retinal and choroidal thickness measurements in obstructive sleep apnea: impacts of continuous positive airway pressure treatment.

To examine retinal and choroidal thicknesses in individuals with obstructive sleep apnea (OSA) and determine the impacts of continuous positive airway pressure (CPAP) treatment. Prospective follow-up study conducted at a university hospital. 40 patients with OSA, 28 treated with CPAP, and 12 untreated, were enrolled immediately after diagnosis and graded according to the apnea hypopnea index (AHI) determined in an overnight polysomnography. Inclusion criteria were a new diagnosis of OSA and CPAP indicated. Participants underwent a full ophthalmologic examination including optical coherence tomography (OCT) at the peripapillary, macular, and choroidal levels and the same examination 3months later. Outcome measures were peripapillary retinal nerve fiber layer (RNFL), total retinal (TRT), retinal ganglion cell layer (RGCL), inner plexiform layer (IPL), photoreceptor layer (PL), and choroidal thicknesses. At 3months, RGCL thickness was reduced at the inner nasal macula segment in the no-CPAP group (P = 0.016). In + CPAP, increases were produced in RNFL thickness (5/6 segments) and TRT (7/ 9 segments), while choroidal thinning was observed temporally (P = 0.003). At baseline, positive correlation was detected between choroidal thickness and AHI (r = 0.352, P = 0.005) and between IPL thickness (7/9 segments) and AHI (r = 0.414, P < 0.001). Initial retinal and choroidal thickening was followed by RGCL thinning over 3months. In patients receiving CPAP, we observed no thinning of any retinal layer and normalization of choroidal thickness.

Reproducibility of Retinal Nerve Fiber Layer and Macular Ganglion Cell Layer Thickness Measurements by Optical Coherence Tomography in Myopic Eyes.

In myopic eyes, reproducibility of circumpapillary retinal nerve fiber layer (RNFL) and macular ganglion cell-inner plexiform layer thickness measurement by optical coherence tomography (OCT) showed excellent reproducibility except for the temporal quadrant RNFL thickness measurement. The aim of this study was to evaluate the long-term reproducibility of circumpapillary RNFL and macular ganglion cell-inner plexiform layer (GCIPL) thickness measurements using OCT in myopic eyes. Sixty-five eyes with moderate-to-high myopia (spherical equivalent <-3.0 D, myopia group) and 53 eyes with low-to-no myopia (spherical equivalent ≥-3.0 D, control group) without ocular disorders, such as glaucoma or retinal diseases, were included. Three serial OCT scans recorded at 1-year intervals were analyzed. Reproducibility was evaluated using within-subject SD (Sw), coefficient of variation (CVw), and intraclass correlation coefficient (ICC). Mean±SD refractive error was -0.30±0.80 and -6.26±2.45 D for control and myopia groups, respectively. The myopia group had thinner superior, inferior, and nasal quadrant RNFL, thicker temporal quadrant RNFL, and thinner GCIPL than the control group (P<0.05), except for the minimum and superotemporal GCIPL thicknesses (P>0.05). The myopia group had lower reproducibility in temporal quadrant RNFL thickness (Sw, 2.57 μm; CVw 3.27%; ICC, 0.979) than the control group (Sw, 1.80 μm; CVw 2.59%; ICC, 0.989), whereas in other sectors of RNFL and all GCIPL parameters, comparable reproducibility was observed between the 2 groups. Long-term reproducibility of RNFL and GCIPL thickness measurements in moderate-to-high myopia was comparable to that of low-to-no myopia, except RNFL thickness in the temporal quadrant. These findings should be considered when detecting RNFL and GCIPL changes.

Bruch Membrane Opening Minimum Rim Width in Neuromyelitis Optica.

Optical coherence tomography (OCT) analyzes the neurodegeneration in neuromyelitis optica (NMO) and multiple sclerosis (MS) and quantifies optical atrophy. The retinal nerve fiber layer (RNFL) and ganglion cell layer (GCL) thickness are decreased, and this structural change is correlated with visual function of patients, including contrast vision and visual field deviation. The main objective of this study was to evaluate the Bruch membrane opening minimum rim width (BMO) of the patients with NMO. We studied the thickness of the BMO by OCT, in patients with NMO (n = 25; 34 eyes), MS (n = 50; 70 eyes), and a control group (n = 51; 100 eyes). The study evaluated the structure-function relationship with the correlation between OCT and visual function: Visual acuity, Pelli-Robson score, Sloan 2.5 and 1.25, color vision, standard automated perimetry (SAP), and frequency-doubling technology perimetry (FDT). The average thickness of BMO was significantly reduced in NMO and MS with or without a history of optic neuritis (ON). Significant thinning of the average, nasal, and inferonasal BMO in the absence of ON in NMO was found compared with controls (P = 0.022, 0.006, and 0.026, respectively). BMO was strongly correlated with Pelli-Robson score (P < 0.001), Sloan 2.5 (P < 0.001), and mean deviation of SAP and FDT (P = 0.004). The sectorial study found a high correlation between the BMO and the corresponding sector of the visual field. The BMO thickness is decreased after ON in NMO and MS. This study showed an improved ability of BMO over RNFL and GCL to detect infraclinical impairment in patients with NMO without a history of optic neuropathy. Like the RNFL and GCL, BMO is well correlated with visual function, including contrast vision and visual field deviation.

Thinning of the inner and outer retinal layers, including the ganglion cell layer and photoreceptor layers, in obstructive sleep apnea and hypopnea syndrome unrelated to the disease severity.

The aim of this study was to analyze the segmented layers of the macula in patients with obstructive sleep apnea and hypopnea syndrome (OSAS) using spectral domain optical coherence tomography (SD-OCT). This single-center, cross-sectional study included 31 OSAS patients and 31 age- and gender-matched control subjects. SD-OCT and overnight polysomnography were performed on all participants. The OSAS patients were categorized according to disease severity (mild, moderate, severe). The groups were compared in respect of each segmented macular layer through the use of segmentation software on SD-OCT. Total retinal thickness (RT), peripapillary retina nerve fiber layer (pRNFL) thickness, central corneal thickness (CCT) and intraocular pressure (IOP) values were also compared between the groups. Mean CCT (p:0.015) and nasal pRNFL values (p:0.042) were lower and mean IOP was higher (p:0.018) in OSAS patients than in the control group. The statistical analysis revealed significantly thinner total RT, inner retinal layers (IRL), outer retinal layers (ORL), photoreceptor layers (PRL) and ganglion cell layer (GCL) thicknesses in the OSAS groups compared to healthy subjects. No significant differences were found between the three OSAS subgroups in all segmented macular layers and pRNFL measurements. The results of this study showed relatively thinner nasal pRNFL, total RT, IRL, ORL, PRL and GCL layers in OSAS patients compared to healthy subjects. Moreover, this thinning of the segmented layers was unrelated to disease severity.

Teaching NeuroImage: Ganglion Cell Patterns Localize Anterior Visual Pathway Lesions.

Measurement of retinal ganglion cell layer thickness by optical coherence tomography provides an objective and reliable evaluation of anterior visual pathway lesions to complement visual field testing in the management of optic chiasm compression from pituitary tumors.1,2 We demonstrated 3 differing patterns of ganglion cell layer thinning—junctional (figure 1, A and D), binasal (figure 1, B and E), and homonymous (figure 1, C and F)—and illustrated how these patterns correspond to the location of chiasmal compression by pituitary adenomas, anteriorly (figure 2A), centrally (figure 2B), or posteriorly (figure 2C). Consideration of the pattern of ganglion cell layer thinning in conjunction with visual field testing is useful for predicting the location of anterior visual pathway lesions.