Retinal Nerve Fiber Layer Atrophy Research Articles

Neutralizing IL-17 protects the optic nerve from autoimmune pathology and prevents retinal nerve fiber layer atrophy during experimental autoimmune encephalomyelitis

Optic neuritis is a common inflammatory manifestation of multiple sclerosis (MS). In experimental autoimmune encephalomyelitis (EAE), the optic nerve is affected as well. Here, we investigated whether autoimmune inflammation in the optic nerve is distinct from inflammation in other parts of the central nervous system (CNS). In our study, inflammatory infiltrates in the optic nerve and the brain were characterized by a high fraction of Ly6G+ granulocytes whereas in the spinal cord, macrophage infiltrates were predominant. At the peak of disease, IL-17 mRNA abundance was highest in the optic nerve as compared with other parts of the CNS. The ratio of IL-17 vs IFN-γ producing CD4+ T cells was higher in the optic nerve and brain than in the spinal cord and more effector CD4+ T cells were committed to the Th17 transcriptional program in the optic nerve than in the spinal cord. IL-17 producing γδ T cells but rather not Ly6G+ granulocytes themselves contributed to IL-17 production. Optical coherence tomography (OCT) studies on murine eyes revealed a decline in thickness of the retinal nerve fiber layer (RNFL) and the common layer of ganglion cells and inner plexiform layer (GCL+) after the recovery from motor symptoms indicating that autoimmune inflammation induced a significant atrophy of optic nerve fibers during EAE. Neutralization of IL-17 by treatment with anti-IL-17 antibodies reduced but did not abrogate motor symptoms of EAE. However, RNFL and GCL+ atrophy were completely prevented by blocking IL-17. Thus, the optic nerve compartment is particularly prone to support IL-17 mediated inflammatory responses during CNS autoimmunity and structural integrity of the retina can be preserved by neutralizing IL-17.

Reliability and validity of Cirrus and Spectralis optical coherence tomography for detecting retinal atrophy in Alzheimer’s disease

To evaluate and compare the ability of two Fourier-domain optical coherence tomography (OCT) devices to detect retinal and retinal nerve fibre layer (RNFL) atrophy in patients with Alzheimer's disease (AD) compared with healthy subjects; to test the intra-session reliability of two OCT devices in AD patients and healthy subjects. AD patients (n=75) and age-matched healthy subjects (n=75) underwent three Macular Cube 200 × 200 protocols using the Cirrus and Spectralis OCT devices and three 360° circular scans centred on the optic disc using the Cirrus OCT device, the classic glaucoma application, and the new Nsite Axonal Analytics application of the Spectralis OCT instrument. Differences between healthy and AD eyes were compared, and measurements provided by each OCT protocol were compared. Reliability was measured using intraclass correlation coefficients and coefficients of variation. Correlations between OCT measurements and disease duration and severity were also analysed. Retinal thinning was observed in AD eyes in all areas except the fovea using both OCT devices. RNFL atrophy was detected in AD eyes with all three protocols, but the Nsite Axonal application was the most sensitive. Measurements by the two OCT devices were correlated, but differed significantly. Reliability was good using all protocols, but better with the glaucoma application of Spectralis. Mean RNFL thickness provided by the Nsite Axonal application correlated with disease duration. Fourier-domain OCT is a valid and reliable technique for detecting subclinical RNFL and retinal atrophy in AD, especially using the Nsite Axonal application. RNFL thickness decreased with disease duration.

Retinal Nerve Fiber Layer Thickness, Brain Atrophy, and Disability in Multiple Sclerosis Patients

To study the relationship between retinal nerve fiber layer (RNFL) thickness and brain atrophy using magnetic resonance imaging (MRI) with bicaudate ratio (BCR) in patients with multiple sclerosis (MS) with different levels of disease severity. We also assessed whether RNFL thickness correlated with Expanded Disability Status Scale (EDSS) score. The participants consisted of 88 patients with MS and 59 age- and sex-matched healthy control subjects. Eleven patients had clinically isolated syndrome (CIS), 68 patients had relapsing-remitting MS (RR-MS), and 9 patients had secondary progressive MS. Patients and controls were evaluated using optical coherence tomography (OCT, Cirrus) and scanning laser polarimetry with variable corneal compensation (GDx VCC). Patients underwent the same brain MRI scanning protocol. Disability was evaluated according to the EDSS. The BCR was calculated by dividing the minimum intercaudate distance by brain width along the same level. The BCR was higher in patients with MS (0.12 ± 0.03) than in controls (0.08 ± 0.009) (P < 0.001). OCT average RNFL thickness in patients with MS was significantly lower (84.51 ± 14.27 μm) than in control subjects (98.44 ± 6.83 μm). BCR was correlated with OCT average RNFL thickness (r = -0.48, P = 0.002) in patients with MS without optic neuritis. Significant correlations were found between average RNFL thickness and EDSS (r = -0.43, P = 0.003). Additionally, there were correlations between BCR with GDx parameters in patients with MS without optic neuritis. This study shows that RNFL thickness correlates with BCR and with MS subtypes. Additionally, our study indicates that OCT is better suited for MS assessment than GDx. We conclude that the damage of retinal axons appears related to brain damage in patients with MS.

Comparison of ability of time-domain and spectral-domain optical coherence tomography to detect diffuse retinal nerve fiber layer atrophy

Our aim was to evaluate and compare diagnostic capabilities of time-domain (Stratus) and spectral-domain (Cirrus) optical coherence tomography (OCT) to detect diffuse retinal nerve fiber layer (RNFL) atrophy. This study assessed 101 eyes from 101 glaucoma patients with diffuse RNFL atrophy and 101 eyes from 101 age-matched healthy individuals. Two experienced glaucoma specialists graded red-free RNFL photographs of eyes with diffuse RNFL atrophy using a four-level grading system. The area under the receiver operating characteristic curves (AUC) of normal eyes was compared with that of eyes with diffuse atrophy. Sensitivity and specificity of each OCT device were calculated on the basis of its internal normative database. The largest AUC for Stratus and Cirrus were obtained for average RNFL thicknesses (0.96 and 0.94, respectively). Comparison of the AUC with different RNFL atrophy grades revealed no significant difference between the two OCT devices. Using an internal normative database at a <5% level, the overall sensitivity of Stratus ranged from 58.0 to 84.0%, whereas that of Cirrus ranged from 75.0 to 87.0%. According to the normative database, the highest Stratus sensitivity was obtained with the temporal-superior-nasal-inferior-temporal (TSNIT) thickness graph, and the highest Cirrus sensitivity with the TSNIT thickness graph and the deviation map. The AUC obtained from Cirrus were comparable with those from Stratus. On the basis of their normative databases, these devices had similar diagnostic accuracy. Our results suggest that the diagnostic capabilities of the two instruments to detect diffuse RNFL atrophy are similar.

Correlation Between Retinal Nerve Fiber Layer Thickness and Visual Field Sensitivity: Diffuse Atrophy Imaging Study

To identify the correlation between retinal nerve fiber layer (RNFL) thickness and visual field sensitivity in healthy eyes with preperimetric and perimetric glaucoma and to estimate the functional RNFL loss in eyes with pre-perimetric glaucoma. One hundred and two eyes with glaucoma and diffuse RNFL atrophy and 102 healthy eyes were enrolled. The correlation between optical coherence tomography (OCT)-measured RNFL thickness of the superior (clock-hour segments 10, 11, 12, 1, 2, and 3) and inferior (clock-hour segments 5, 6, 7, and 8) area and the average total deviations of the inferior and superior hemifields in standard automated perimetry (SAP) were evaluated using the simple linear model, respectively. The OCT-measured RNFL thickness was assumed to comprise functional and residual thicknesses; the residual thickness was calculated from the simple linear model and the eyes with severe diffuse RNFL atrophy. Functional RNFL thickness was compared between groups. Twenty-seven eyes had preperimetric and 75 eyes had perimetric glaucoma. The coefficient of determination (R(2)) of the simple linear model was 0.71 to 0.77 for the correlation between RNFL thickness and total deviation of SAP. The estimated residual thickness was 50.4 to 56.5 μm. On comparison with normal eyes, eyes with preperimetric glaucoma were estimated to have 37% to 41% functional RNFL loss. The correlation between RNFL thickness and SAP sensitivity was well explained by the simple linear model. Approximately 40% loss of the functional RNFL was found in preperimetric glaucoma.

Retinal Nerve Fiber Layer Atrophy Is Associated With Visual Field Loss Over Time in Glaucoma Suspect and Glaucomatous Eyes

To compare prospectively detection of progressive retinal nerve fiber layer thickness (RNFL) atrophy identified using time-domain optical coherence tomography with visual field progression using standard automated perimetry in glaucoma suspect and preperimetric glaucoma patients or perimetric glaucoma patients. Prospective, longitudinal clinical trial. Eligible eyes with 2 years or more of follow-up underwent time-domain optical coherence tomography and standard automated perimetry every 6months. The occurrence of visual field progression was defined as the first follow-up visit reaching a significant (P < .05) negative visual field index slope over time. RNFL progression or improvement was defined as a significant negative or positive slope over time, respectively. Specificity was defined as the number of eyes with neither progression nor improvement, divided by the number of eyes without progression. Cox proportional hazard ratios were calculated using univariate and multivariate models with RNFL loss as a time-dependent covariate. Three hundred ten glaucoma suspect and preperimetric glaucoma eyes and 177 perimetric glaucoma eyes were included. Eighty-nine eyes showed visual field progression and 101 eyes showed RNFL progression. The average time to detect visual field progression in those 89 eyes was 35 ± 13months, and the average time to detect RNFL progression in those 101 eyes was 36 ± 13months. In multivariate Cox models, average and superior RNFL losses were associated with subsequent visual field index loss in the entire cohort (every 10-μm loss; hazard ratio, 1.38; P= .03; hazard ratio, 1.20; P= .01; respectively). Among the entire cohort of 487 eyes, 42 had significant visual field index improvement and 55 had significant RNFL improvement (specificity, 91.4% and 88.7%, respectively). Structural progression is associated with functional progression in glaucoma suspect and glaucomatous eyes. Average and superior RNFL thickness may predict subsequent standard automated perimetry loss.

OPTICAL COHERENCE TOMOGRAPHY IN RETINITIS PIGMENTOSA

In Brief Purpose: To evaluate the ability of time-domain and Fourier-domain optical coherence tomographies (OCTs) to detect macular and retinal nerve fiber layer atrophies in retinitis pigmentosa (RP). To test the intrasession reproducibility using three OCT instruments (Stratus, Cirrus, and Spectralis). Methods: Eighty eyes of 80 subjects (40 RP patients and 40 healthy subjects) underwent a visual field examination, together with 3 macular scans and 3 optic disk evaluations by the same experienced examiner using 3 OCT instruments. Differences between healthy and RP eyes were compared. The relationship between measurements with each OCT instrument was evaluated. Repeatability was studied by intraclass correlation coefficients and coefficients of variation. Results: Macular and retinal nerve fiber layer atrophies were detected in RP patients for all OCT parameters. Macular and retinal nerve fiber layer thicknesses, as determined by the different OCTs, were correlated but significantly different (P < 0.05). Reproducibility was moderately high using Stratus, good using Cirrus and Spectralis, and excellent using the Tru-track technology of Spectralis. In RP eyes, measurements showed higher variability compared with healthy eyes. Conclusion: Differences in thickness measurements existed between OCT instruments, despite there being a high degree of correlation. Fourier-domain OCT can be considered a valid and repeatability technique to detect retinal nerve fiber layer atrophy in RP patients. Time-domain and Fourier-domain optical coherence tomographies are useful to detect macular and retinal nerve fiber layer atrophies in retinitis pigmentosa patients compared with healthy subjects, but reproducibility is higher using Cirrus and Spectralis instruments than using Stratus.

Ability and Reproducibility of Fourier-Domain Optical Coherence Tomography to Detect Retinal Nerve Fiber Layer Atrophy in Parkinson's Disease

To evaluate and compare the ability of 3 protocols of Fourier-domain optical coherence tomography (OCT) to detect retinal thinning and retinal nerve fiber layer (RNFL) atrophy in patients with Parkinson's disease (PD) compared with healthy subjects. To test the intrasession reproducibility of RNFL thickness measurements in patients with PD and healthy subjects using the Cirrus (Carl Zeiss Meditec Inc., Dublin, CA) and Spectralis (Heidelberg Engineering, Inc., Heidelberg, Germany) OCT devices. Observational, cross-sectional study. Patients with PD (n = 75) and age-matched healthy subjects (n = 75) were enrolled. All subjects underwent three 360-degree circular scans centered on the optic disc by the same experienced examiner using the Cirrus OCT instrument, the classic glaucoma application, and the new Nsite Axonal Analytics of the Spectralis OCT instrument. Differences between the eyes of healthy subjects and the eyes of patients with PD were compared using the 3 protocols. The relationship between measurements provided by each OCT protocol was evaluated. Repeatability was studied by intraclass correlation coefficients and coefficients of variation. Retinal nerve fiber layer atrophy was detected in eyes of patients with PD (P = 0.025, P=0.042, and P < 0.001) with the 3 protocols used, but the Nsite Axonal Analytics of the Spectralis OCT device was the most sensitive for detecting subclinical defects. In eyes of patients with PD, RNFL thickness measurements determined by the OCT devices were correlated, but they were significantly different between the Cirrus and Spectralis devices (P = 0.038). Reproducibility was good with all 3 protocols but better using the Glaucoma application of the Spectralis OCT device. Fourier-domain OCT can be considered a valid and reproducible device for detecting subclinical RNFL atrophy in patients with PD, especially the Nsite Axonal Analytics of the Spectralis device. Retinal nerve fiber layer thickness measurements differed significantly between the Cirrus and Spectralis devices despite a high correlation of the measurements between the 2 instruments.

Diagnostic Accuracy of OCT with a Normative Database to Detect Diffuse Retinal Nerve Fiber Layer Atrophy: Diffuse Atrophy Imaging Study

To investigate the diagnostic accuracy of Stratus optical coherence tomography (OCT) with its internal normative database to detect diffuse retinal nerve fiber layer (RNFL) atrophy in glaucoma subjects. One hundred two eyes of 102 glaucoma patients with diffuse RNFL atrophy and 102 healthy eyes of 102 age-matched subjects were enrolled in the Diffuse Atrophy Imaging Study. Two experienced observers graded RNFL photographs of diffuse RNFL atrophy eyes using a four-level grading system. The diagnostic performances for detecting diffuse RNFL atrophy were examined according to visual field results and RNFL photograph grading. Using a criterion of abnormal at the <5% level, the overall sensitivity of the Stratus OCT parameters ranged from 61.5% to 84.5%, and the overall specificity ranged from 90.2% to 99.0%. For mild, moderate, and severe diffuse RNFL atrophy, the superior quadrant had a sensitivity of 41.0%, 83.3%, and 100.0%, respectively, and the inferior quadrant had a sensitivity of 35.0%, 88.5%, and 100.0%, respectively. The highest likelihood ratios were obtained at the 11 and 12 o'clock sectors for superior RNFL and the 6 and 7 o'clock sectors for inferior RNFL. OCT with a normative database can detect diffuse RNFL atrophy with moderate sensitivity and high specificity. Because the sensitivity of Stratus OCT is closely related to the degree of diffuse RNFL atrophy and the visual field results, OCT with an internal normative database should be evaluated with prudence, especially in the early stage of glaucoma with diffuse RNFL atrophy.

Risk factors for progressive axonal degeneration of the retinal nerve fibre layer in multiple sclerosis patients

AimTo quantify structural and functional degeneration in the retinal nerve fibre layer (RNFL) of patients with multiple sclerosis (MS) over a 2-year time period, and to analyse the effect of...

Fourier-Domain OCT in Multiple Sclerosis Patients: Reproducibility and Ability to Detect Retinal Nerve Fiber Layer Atrophy

To evaluate the ability of Fourier-domain (FD) optical coherence tomography (OCT) to detect retinal nerve fiber layer (RNFL) atrophy in multiple sclerosis (MS) patients. To test the intrasession reproducibility of RNFL thickness measurements in MS and healthy subjects using Cirrus (Carl Zeiss Meditec, Dublin, CA) and Spectralis (Heidelberg Engineering, Heidelberg, Germany) OCT. Two hundred twenty-two eyes of 111 subjects (50 MS patients and 61 healthy subjects) underwent three 360° circular scans centered on the optic disc by the same experienced examiner using the Cirrus and Spectralis OCT instruments. Differences between healthy and MS eyes were compared. The relationship between average thicknesses with each OCT was evaluated. Repeatability was studied by intraclass correlation coefficients and coefficients of variation (COV). RNFL atrophy was detected in the MS eyes for all OCT parameters (P < 0.05). Cirrus and Spectralis showed an RNFL average thickness of 99.4 and 102.5 μm, respectively, in healthy subjects, and 86.0 and 90.4 μm in the MS eyes. RNFL average thickness in the MS eyes determined by both OCTs correlated (r = 0.812; P < 0.001), but were significantly different (P < 0.001). Reproducibility was good. In the MS eyes, Cirrus measurements showed a mean COV of 5.85%, Spectralis 6.80%, and Spectralis with a progression feature 4.16%. Intraclass correlation coefficients were higher than 0.840. RNFL average thickness correlated with disease duration and an optic neuritis antecedent. There are significant differences in RNFL thickness measurements between Cirrus and Spectralis despite a high correlation of measurement between the two instruments. Fourier-domain OCT can be considered a valid device for detecting RNFL atrophy in MS patients.

Interpretation of RNFLT values in multiple sclerosis‐associated acute optic neuritis using high‐resolution SD‐OCT device

Optical coherence tomography (OCT) has emerged as the technique of choice in measuring the retinal nerve fibre layer (RNFL) quantitatively. It is suggested that RNFL reduction may correlate with lesion burden and diffuse axonal degeneration in the whole CNS of patients with multiple sclerosis (MS). However, RNFL changes because of optic neuritis (ON) must be taken into account. Twenty-three patients with acute ON (46 eyes) associated with clinical definite MS (23 ON eyes, 23 fellow eyes) and 23 sex- and age-matched healthy controls were studied. Retinal nerve fibre layer thickness (RNFLT) was measured at baseline, using a high-resolution spectral domain OCT (SD-OCT) applying circular, peripapillary OCT scans with a novel eye-tracking mechanism. The internal OCT software was able to identify RNFL atrophy in three out of five of the acute ON eyes and one out of four of the fellow eyes with previous ON episodes. Retinal nerve fibre layer thickness of two ON (8.7%) and five fellow eyes (21.7%) was overestimated, thus located within the 95% and 5% confidence interval of the company standard values (not marked pathologic). In contrast, our comparison with age- and sex-matched controls revealed RNFL atrophy suggestive of prior, clinically silent RNFL loss in ON and fellow eyes (30.4%). Retinal nerve fibre layer thickness measurements at a single time-point seem to have a limited role in detecting prior clinically silent optic nerve injury. Our data suggest that affected eyes should be compared with the fellow eyes and a sufficient number of age- and sex-matched controls to allow the detection of even subtle RNFL changes at baseline. The role of OCT for disease monitoring of MS must be evaluated in detail, as ON is often the initial symptom of MS.

Evolution of visual field defects and alterations of the retinal nerve fiber layer in the pituitary macroadenoma

Abstract Purpose To evaluate the evolution of the visual field defects and the alterations of the retinal nerve fiber layer (RNFL), which are produced in intracranial neoplasms that affect the visual pathway. Methods Description of a clinical case. 44 years old male with a prolactin‐producing pituitary macroadenoma. The patient presented progressive defects in the visual field (bitemporal hemianopsia), observed by standard automated perimetry (SAP) (Humphrey, SITA Standard 30.2), and RNFL atrophy evaluated by means of monochromatic fiber photography, optical coherence tomography (OCT) and laser polarimetry (GDx VCC). Results An uncompleted removal of the tumor was performed by transsphenoidal approach. It was observed a mild and progressive recuperation of the visual field defects. The RNFL alterations did not show any change. Conclusion The visual field defects caused by intracranial space‐occupying tumors, may improved after resection of the tumor. Structural alterations in the RNFL remain stable.

Quantitative Assessment of Diffuse Retinal Nerve Fiber Layer Atrophy Using Optical Coherence Tomography: Diffuse Atrophy Imaging Study

To evaluate quantitatively the degree of diffuse retinal nerve fiber layer (RNFL) atrophy using Stratus optical coherence tomography (OCT). Prospective, cross-sectional study. One hundred two eyes of 102 patients with diffuse RNFL atrophy and 102 healthy eyes of 102 age-matched subjects were enrolled in the Diffuse Atrophy Imaging Study. Two experienced observers graded RNFL photographs of diffuse RNFL atrophy eyes using a previously reported standardized protocol with a 4-level grading system. Readings were taken from the superior and inferior RNFL areas. The OCT-measured RNFL thickness parameters were compared among normal eyes and diffuse atrophy subgroups. Area under the receiver operating characteristic curves (AROCs) was calculated for various OCT RNFL parameters. Average and segmental (4 quadrants and 12 clock-hours) OCT-measured RNFL thicknesses and AROCs for various OCT parameters. For superior and inferior RNFL areas, diffuse atrophy grading by 2 observers agreed in 82.5% and 83.3% of cases, respectively, with a substantial agreement (kappa value = 0.760 [P < 0.001] and 0.777 [P < 0.001]). Significant differences were observed in RNFL thickness among normal and all diffuse atrophy subgroups, especially in the 7 and 11 o'clock sectors (P < 0.0001). The OCT RNFL thickness measurements decreased with increasing severity of RNFL damage. The 7 and 11 o'clock sectors showed the highest AROCs for discrimination of mild RNFL atrophy from normal eyes (0.972 and 0.979, respectively). The OCT RNFL thickness parameters showed excellent quantitative correlation with the degree of diffuse RNFL atrophy. Our results suggest that Stratus OCT may serve as a useful adjunct in accurately and objectively assessing the degree of diffuse RNFL atrophy.

Retinal nerve fiber layer atrophy as relevant feature for diffuse unilateral subacute neuroretinitis (DUSN): case series

To report the findings of optical coherence tomography (OCT) in three cases of diffuse unilateral subacute neuroretinitis (DUSN). Three young patients with confirmed diagnosis of diffuse unilateral subacute neuroretinitis were followed-up using Stratus OCT. Optical coherence tomography findings included retinal nerve fiber layer atrophy and focal edema where the worm was initially lodged. In two patients we could identify the worm by optical coherence tomography as an area of hiper-reflectivity. The worms were laser photocoagulated and post-treatment optical coherence tomography scanning revealed improvement of edema, nerve fiber layer thinning and a retinal hyper-reflectivity where laser had been applied. The main finding reported here is the potential of optical coherence tomography in detecting the presence of retinal nerve fiber layer atrophy and focal retinal edema in areas affected by the worm. Optical coherence tomography can be used to distinguish diffuse unilateral subacute neuroretinitis from other mimicking diseases like punctate outer retinitis, when there are no retinal fiber layer atrophy.

Diffuse Glaucomatous Structural and Functional Damage in the Hemifield Without Significant Pattern Loss

To compare the retinal nerve fiber layer (RNFL) thickness and retinal sensitivity in the normal visual hemifield of glaucomatous eyes with localized visual field loss with those of normal eyes and eyes with suspected glaucoma, and to evaluate the relationship between RNFL atrophy and glaucoma severity. One randomly selected eye of each subject underwent standard automated perimetry, stereoscopic photography, scanning laser polarimetry with enhanced corneal compensation, and time-domain and spectral-domain optical coherence tomography (OCT). Mean retinal sensitivity values were calculated in the normal standard automated perimetry hemifield of the glaucoma group and randomly selected hemifields in the normal and suspected glaucoma groups. The mean RNFL thickness values corresponding to the normal hemifield were calculated. Glaucoma severity was judged using standard automated perimetry pattern standard deviation and the Heidelberg retina tomograph-derived linear cup-disc ratio. Fifty subjects were enrolled in each group. Mean RNFL thickness in the normal hemifield obtained using spectral-domain OCT, time-domain OCT, and scanning laser polarimetry with enhanced corneal compensation was significantly (P <or= .01) thinner in the glaucoma group compared with the normal and suspected glaucoma groups. Mean retinal sensitivity in the normal hemifield was significantly (P < .001) reduced in the glaucoma group compared with the normal and suspected glaucoma groups. The Heidelberg retina tomograph-derived cup-disc ratio was significantly correlated with mean RNFL thickness in the normal hemifield obtained using spectral-domain OCT, time-domain OCT, and scanning laser polarimetry with enhanced corneal compensation (P <or= .01). Diffuse RNFL atrophy and retinal sensitivity loss exist in glaucomatous eyes with localized standard automated perimetry deficits. Glaucomatous damage affects both structure and function in a linear proportion.

Differences in retinal nerve fiber layer atrophy between multiple sclerosis subtypes

Objectives To determine whether retinal nerve fiber layer (RNFL) atrophy in the afferent visual pathway may complement existing tools used to describe and characterize differences across MS subtypes. Methods Optical coherence tomography-measured RNFL values were compared over two years in 35 patients (70 eyes) with optic neuritis (ON) as a clinically isolated syndrome (CIS); 39 patients (78 eyes) with relapsing remitting MS (RRMS); and 7 patients (14 eyes) with secondary progressive MS (SPMS). Results RNFL comparisons involving eyes without ON yielded greater differences between MS subtypes than ON-affected eyes. Overall RNFL values in non-affected eyes were reduced in SPMS patients (83.4 μm), relative to CIS (101.2 μm) ( p = 0.0009), and RRMS patients (103.7 μm) ( p = 0.001); and temporal RNFL atrophy was greater in RRMS (64.4 μm) eyes as compared to CIS eyes (73.2 μm) ( p = 0.02). In ON-affected eyes, RNFL atrophy was greater in SPMS patients (39.5 μm) than CIS patients (58.1 μm) ( p = 0.03), and in RRMS patients (48.2 μm) relative to CIS patients ( p = 0.05). RNFL values did not change significantly for any MS subtype during the two-year duration of the study. Interpretation RNFL thickness may represent a structural marker, which can help distinguish MS subtypes, because the extent of atrophy is commensurate with disease progression. RNFL comparisons between non-affected eyes revealed greater differences between CIS, RRMS, and SPMS patients relative to ON-affected eyes, because the impact of prior ON may supplant the effects of disease subtype.

Comparison of retinal nerve fibre layers between 11778 and 14484 mutations in Leber's hereditary optic neuropathy

To compare retinal nerve fibre layer (RNFL) thickness changes between mitochondrial DNA (mtDNA) mutations at nucleotides 11778 and 14484 in Leber's hereditary optic neuropathy (LHON) using optical coherence tomography (OCT). Thirty LHON patients with mtDNA mutations at nucleotides 11778 or 14484 underwent full ophthalmologic examinations including Stratus OCT. Patients were divided into four groups according to disease duration (early <or=6 months, late >6 months) and mtDNA mutation type (11778 and 14484), and their RNFL thicknesses were compared. Average RNFL thickness in the early 11778 group was significantly greater than that in the early 14484 group (P=0.04). Average RNFL thickness in the late 11778 group was significantly less than that in the late 14484 group (P=0.02). Quadrant analysis of the superior, nasal, and inferior quadrant RNFL thickness in the late 11778 group showed more severe RNFL atrophy than in the late 14484 group (P=0.023, 0.015, 0.003, respectively). RNFL thickness was significantly increased in the early stage and decreased in the late stage in the 11778 group than in the 14484 group.

Ocular Toxoplasmosis Presenting With Focal Retinal Nerve Fiber Atrophy Simulating Glaucoma

We describe a patient with ocular hypertension and nonglaucomatous retinal nerve fiber layer (RNFL) atrophy associated with an ocular toxoplasmosis retinal lesion. Single case report. An RNFL defect was identified adjacent to a circumscribed pigmented chorioretinal lesion superior to the macular region. The optic disc showed a prominent central cup without focal neural rim atrophy. Red-free photography and RNFL imaging using optical coherence tomography and scanning laser polarimetry showed corresponding focal RNFL atrophy. The toxoplasmosis lesion was characterized by an apparent full thickness disruption in retinal architecture, including the retinal ganglion cell layer, using spectral-domain optical coherence tomography. Nonglaucomatous retinal lesions may simulate glaucomatous RNFL atrophy and visual field loss, particularly when focal damage to the retinal ganglion cells occurs. Careful inspection of the retina and optic disc, with attention to the integrity of the neural rim, and analysis of the pattern of RNFL loss in proximity to a retinal lesion may enable the clinician to differentiate glaucomatous and nonglaucomatous pathogenic mechanisms.

Ability of Stratus OCT to Detect Progressive Retinal Nerve Fiber Layer Atrophy in Glaucoma

To evaluate the ability of Stratus optical coherence tomography (OCT version 4.0; Carl Zeiss Meditec, Inc., Dublin, CA) to detect progressive glaucomatous retinal nerve fiber layer (RNFL) atrophy observed by red-free RNFL photography. Intersession test-retest variability of each clock hour, quadrant, and average RNFL thickness was determined in 53 control subjects. The sensitivity and specificity of OCT for identification of progressive RNFL atrophy were tested on subjects in whom this condition was clearly observed in red-free RNFL photographs (n=27) and in another control group (n=62), according to criteria derived from test-retest variability. The sensitivity of Stratus OCT RNFL measurement ranged from 14.8% (for average RNFL thickness) to 85.2% (for clock hour thickness) when tested at the 95% confidence level. The specificity of Stratus OCT RNFL measurement was approximately 95% for average RNFL thickness, but decreased considerably with clock hour (59.7%) and quadrant thickness (77.4%). This is presumably because multiple testing was used for multiple clock hours and quadrants. When calculated based on two consecutive follow-up examinations, the specificity for the clock hour measurements increased to 86.6% and that for quadrant thickness increased to 92.5%. The OCT-measured RNFL thickness change showed excellent topographic agreement with the progressive RNFL atrophy observed using RNFL photography. Within the limits of retest variability, Stratus OCT detects progressive RNFL atrophy with high sensitivity and moderate specificity in cases showing localized progressive loss of retinal nerve fibers in red-free photographs. The specificity can be improved by use of multiple measurements. Stratus OCT is a potentially useful technique for detection of glaucoma progression.