70 research outputs found
Retinal inner nuclear layer volume reflects inflammatory disease activity in multiple sclerosis: a longitudinal OCT study
Inner nuclear layer; Multiple sclerosis; Optical coherence tomographyCapa nuclear interna; Esclerosis mĂşltiple; TomografĂa de coherencia ĂłpticaCapa nuclear interior; Esclerosi mĂşltiple; Tomografia de coherència òpticaBackground: The association of peripapillary retinal nerve fibre layer (pRNFL) and ganglion cell-inner plexiform layer (GCIPL) thickness with neurodegeneration in multiple sclerosis (MS) is well established. The relationship of the adjoining inner nuclear layer (INL) with inflammatory disease activity is less well understood. Objective: The objective of this paper is to investigate the relationship of INL volume changes with inflammatory disease activity in MS. Methods In this longitudinal, multi-centre study, optical coherence tomography (OCT) and clinical data (disability status, relapses and MS optic neuritis (MSON)) were collected in 785 patients with MS (68.3% female) and 92 healthy controls (63.4% female) from 11 MS centres between 2010 and 2017 and pooled retrospectively. Data on pRNFL, GCIPL and INL were obtained at each centre. Results: There was a significant increase in INL volume in eyes with new MSON during the study (N=61/1562, β=0.01mm3, p<.001). Clinical relapses (other than MSON) were significantly associated with increased INL volume (β=0.005, p=.025). INL volume was independent of disease progression (β=0.002mm3, p=.474). Conclusion: Our data demonstrate that an increase in INL volume is associated with MSON and the occurrence of clinical relapses. Therefore, INL volume changes may be useful as an outcome marker for inflammatory disease activity in MSON and MS treatment trials
Monitoring retinal changes with optical coherence tomography predicts neuronal loss in experimental autoimmune encephalomyelitis.
BACKGROUND:Retinal optical coherence tomography (OCT) is a clinical and research tool in multiple sclerosis, where it has shown significant retinal nerve fiber (RNFL) and ganglion cell (RGC) layer thinning, while postmortem studies have reported RGC loss. Although retinal pathology in experimental autoimmune encephalomyelitis (EAE) has been described, comparative OCT studies among EAE models are scarce. Furthermore, the best practices for the implementation of OCT in the EAE lab, especially with afoveate animals like rodents, remain undefined. We aimed to describe the dynamics of retinal injury in different mouse EAE models and outline the optimal experimental conditions, scan protocols, and analysis methods, comparing these to histology to confirm the pathological underpinnings. METHODS:Using spectral-domain OCT, we analyzed the test-retest and the inter-rater reliability of volume, peripapillary, and combined horizontal and vertical line scans. We then monitored the thickness of the retinal layers in different EAE models: in wild-type (WT) C57Bl/6J mice immunized with myelin oligodendrocyte glycoprotein peptide (MOG35-55) or with bovine myelin basic protein (MBP), in TCR2D2 mice immunized with MOG35-55, and in SJL/J mice immunized with myelin proteolipid lipoprotein (PLP139-151). Strain-matched control mice were sham-immunized. RGC density was counted on retinal flatmounts at the end of each experiment. RESULTS:Volume scans centered on the optic disc showed the best reliability. Retinal changes during EAE were localized in the inner retinal layers (IRLs, the combination of the RNFL and the ganglion cell plus the inner plexiform layers). In WT, MOG35-55 EAE, progressive thinning of IRL started rapidly after EAE onset, with 1/3 of total loss occurring during the initial 2 months. IRL thinning was associated with the degree of RGC loss and the severity of EAE. Sham-immunized SJL/J mice showed progressive IRL atrophy, which was accentuated in PLP-immunized mice. MOG35-55-immunized TCR2D2 mice showed severe EAE and retinal thinning. MBP immunization led to very mild disease without significant retinopathy. CONCLUSIONS:Retinal neuroaxonal damage develops quickly during EAE. Changes in retinal thickness mirror neuronal loss and clinical severity. Monitoring of the IRL thickness after immunization against MOG35-55 in C57Bl/6J mice seems the most convenient model to study retinal neurodegeneration in EAE
The OSCAR-IB Consensus Criteria for Retinal OCT Quality Assessment
Retinal optical coherence tomography (OCT) is an imaging biomarker for neurodegeneration in multiple sclerosis (MS). In order to become validated as an outcome measure in multicenter studies, reliable quality control (QC) criteria with high inter-rater agreement are required
Retinal inner nuclear layer volume reflects inflammatory disease activity in multiple sclerosis;a longitudinal OCT study
Background: The association of peripapillary retinal nerve fibre layer (pRNFL) and ganglion cell-inner plexiform layer (GCIPL) thickness with neurodegeneration in multiple sclerosis (MS) is well established. The relationship of the adjoining inner nuclear layer (INL) with inflammatory disease activity is less well understood. Objective: The objective of this paper is to investigate the relationship of INL volume changes with inflammatory disease activity in MS. Methods In this longitudinal, multi-centre study, optical coherence tomography (OCT) and clinical data (disability status, relapses and MS optic neuritis (MSON)) were collected in 785 patients with MS (68.3% female) and 92 healthy controls (63.4% female) from 11 MS centres between 2010 and 2017 and pooled retrospectively. Data on pRNFL, GCIPL and INL were obtained at each centre. Results: There was a significant increase in INL volume in eyes with new MSON during the study (N = 61/1562, beta = 0.01mm(3), p<.001). Clinical relapses (other than MSON) were significantly associated with increased INL volume (beta = 0.005, p =.025). INL volume was independent of disease progression (beta = 0.002mm(3), p =.474). Conclusion: Our data demonstrate that an increase in INL volume is associated with MSON and the occurrence of clinical relapses. Therefore, INL volume changes may be useful as an outcome marker for inflammatory disease activity in MSON and MS treatment trials
A Simple Sign for Recognizing Off-Axis OCT Measurement Beam Placement in the Context of Multicentre Studies
Optical coherence tomography (OCT) allows quantification of the thickness of the retinal nerve fibre layer (RNFL) thickness, a potential biomarker for neurodegeneration. The estimated annual RNFL loss in multiple sclerosis amounts to 2 ÎĽm using time domain OCT. The recognition of measurement artifacts exceeding this limit is relevant for the successful use of OCT as a secondary outcome measure in clinical trials
Normative Data and Conversion Equation for Spectral-Domain Optical Coherence Tomography in an International Healthy Control Cohort
Background:Spectral-domain (SD-) optical coherence tomography (OCT) can reliably measure axonal (peripapillary retinal nerve fiber layer [pRNFL]) and neuronal (macular ganglion cell + inner plexiform layer [GCIPL]) thinning in the retina. Measurements from 2 commonly used SD-OCT devices are often pooled together in multiple sclerosis (MS) studies and clinical trials despite software and segmentation algorithm differences; however, individual pRNFL and GCIPL thickness measurements are not interchangeable between devices. In some circumstances, such as in the absence of a consistent OCT segmentation algorithm across platforms, a conversion equation to transform measurements between devices may be useful to facilitate pooling of data. The availability of normative data for SD-OCT measurements is limited by the lack of a large representative world-wide sample across various ages and ethnicities. Larger international studies that evaluate the effects of age, sex, and race/ethnicity on SD-OCT measurements in healthy control participants are needed to provide normative values that reflect these demographic subgroups to provide comparisons to MS retinal degeneration.Methods:Participants were part of an 11-site collaboration within the International Multiple Sclerosis Visual System (IMSVISUAL) consortium. SD-OCT was performed by a trained technician for healthy control subjects using Spectralis or Cirrus SD-OCT devices. Peripapillary pRNFL and GCIPL thicknesses were measured on one or both devices. Automated segmentation protocols, in conjunction with manual inspection and correction of lines delineating retinal layers, were used. A conversion equation was developed using structural equation modeling, accounting for clustering, with healthy control data from one site where participants were scanned on both devices on the same day. Normative values were evaluated, with the entire cohort, for pRNFL and GCIPL thicknesses for each decade of age, by sex, and across racial groups using generalized estimating equation (GEE) models, accounting for clustering and adjusting for within-patient, intereye correlations. Change-point analyses were performed to determine at what age pRNFL and GCIPL thicknesses exhibit accelerated rates of decline.Results:The healthy control cohort (n = 546) was 54% male and had a wide distribution of ages, ranging from 18 to 87 years, with a mean (SD) age of 39.3 (14.6) years. Based on 346 control participants at a single site, the conversion equation for pRNFL was Cirrus = -5.0 + (1.0 Ă— Spectralis global value). Based on 228 controls, the equation for GCIPL was Cirrus = -4.5 + (0.9 Ă— Spectralis global value). Standard error was 0.02 for both equations. After the age of 40 years, there was a decline of -2.4 m per decade in pRNFL thickness (P < 0.001, GEE models adjusting for sex, race, and country) and -1.4 m per decade in GCIPL thickness (P < 0.001). There was a small difference in pRNFL thickness based on sex, with female participants having slightly higher thickness (2.6 m, P = 0.003). There was no association between GCIPL thickness and sex. Likewise, there was no association between race/ethnicity and pRNFL or GCIPL thicknesses.Conclusions:A conversion factor may be required when using data that are derived between different SD-OCT platforms in clinical trials and observational studies; this is particularly true for smaller cross-sectional studies or when a consistent segmentation algorithm is not available. The above conversion equations can be used when pooling data from Spectralis and Cirrus SD-OCT devices for pRNFL and GCIPL thicknesses. A faster decline in retinal thickness may occur after the age of 40 years, even in the absence of significant differences across racial groups
APOSTEL 2.0 Recommendations for Reporting Quantitative Optical Coherence Tomography Studies.
OBJECTIVE
To update the consensus recommendations for reporting of quantitative optical coherence tomography (OCT) study results, thus revising the previously published Advised Protocol for OCT Study Terminology and Elements (APOSTEL) recommendations.
METHODS
To identify studies reporting quantitative OCT results, we performed a PubMed search for the terms "quantitative" and "optical coherence tomography" from 2015 to 2017. Corresponding authors of the identified publications were invited to provide feedback on the initial APOSTEL recommendations via online surveys following the principle of a modified Delphi method. The results were evaluated and discussed by a panel of experts and changes to the initial recommendations were proposed. A final survey was recirculated among the corresponding authors to obtain a majority vote on the proposed changes.
RESULTS
A total of 116 authors participated in the surveys, resulting in 15 suggestions, of which 12 were finally accepted and incorporated into an updated 9-point checklist. We harmonized the nomenclature of the outer retinal layers, added the exact area of measurement to the description of volume scans, and suggested reporting device-specific features. We advised to address potential bias in manual segmentation or manual correction of segmentation errors. References to specific reporting guidelines and room light conditions were removed. The participants' consensus with the recommendations increased from 80% for the previous APOSTEL version to greater than 90%.
CONCLUSIONS
The modified Delphi method resulted in an expert-led guideline (evidence Class III; Grading of Recommendations, Assessment, Development and Evaluations [GRADE] criteria) concerning study protocol, acquisition device, acquisition settings, scanning protocol, funduscopic imaging, postacquisition data selection, postacquisition analysis, nomenclature and abbreviations, and statistical approach. It will be essential to update these recommendations to new research and practices regularly
Satisfaction among Museum Visitors: The Holistic Approach Confirmed Empirical Evidence from the Anne Frank House Visitors
Abstract This paper examines whether a holistic element affected the valuations of visitors to the Anne Frank House, an en-site historical museum. The holistic approach views a museum as a whole entity and not as the sum of individual items. For the purposes of our research, we developed a new set of instruments, based on a literature survey and practical experience. We collected our data by interviewing over 2,000 visitors to the world-renowned Anne Frank House during 1998 and 1999. Our findings show that visitors clearly view this museum from a holistic perspective: overall satisfaction was greater than satisfaction regarding any individual items. In this respect, the holistic approach appeals especially to younger people, Europeans and people of higher educational backgrounds. While the conclusions of this research project apply exclusively to the Anne Frank House, the innovative approach used to measure visitor satisfaction can be applied to any en-site historica! museum or similar tourist attraction.Museums; Satisfaction; Consumer behaviour; Services
Positive association between dietary iron intake and iron status in HIV-infected children in Johannesburg, South Africa
Anemia is a common complication of pediatric HIV infection and is associated with
suboptimal cognitive performance and growth failure. Routine iron supplementation is not
provided to South African HIV-infected children. We hypothesized that dietary iron intake
without supplementation is sufficient to protect against iron deficiency (ID) in HIV-infected
children receiving highly active antiretroviral therapy. In this prospective study, the
difference between dietary intakes of iron-deficient children (soluble transferrin receptor
>9.4 mg/L) and iron-sufficient children after 18 months on highly active antiretroviral
therapy was examined. The association between iron intake and hemoglobin (Hb)
concentration was also assessed. Longitudinal data collected for 18 months from 58 HIVinfected
African children were assessed by generalized estimation equations, with
adjustment for demographic information, dietary intakes, growth parameters, and CD4%.
After adjustment for covariates, the longitudinal association between dietary iron intake
and Hb concentration remained significant. This association shows that for every 1-mg
increase in iron intake per day, Hb increases by 1.1 g/L (P < .001). Mean Hb increased
significantly after 18 months of follow-up (106 ± 14 to 129 ± 14 g/L, P < .01), but soluble
transferrin receptor also increased (7.7 ± 2.7 to 8.9 ± 3.0 mg/L, P < .01). The incidence of ID
increased from 15.2% at baseline to 37.2% after 18 months. Children with animal protein
intakes greater than >20 g/d had significantly lower odds for ID at 18 months than did
children with lower intakes (odds ratio, 0.40; 95% confidence interval, 0.21-0.77). Dietary iron
intake was insufficient to protect against ID, pointing to a need for low-dose iron
supplementation for iron-deficient HIV-infected children and interventions to increase
the consumption of animal protein
- …