Value of the central vein sign at 3T to differentiate MS from seropositive NMOSD

Central vein sign for multiple sclerosis: A systematic review and meta-analysis

AIMS

To systematically review the diagnostic value of the central vein sign (CVS) in multiple sclerosis (MS) and to meta-analyse the proportion of positive lesions for CVS needed to distinguish MS from non-MS mimics.

MATERIALS AND METHODS

A literature review was performed and a proportion meta-analysis was performed to examine the proportion of the CVS in MS lesions. Studies reporting a threshold of the CVS containing lesions with 100% diagnostic accuracy were included in the meta-analysis. This was compared to MS mimics in order to establish the discriminative value of the CVS.

RESULTS

The CVS was found to be viable at lower field strengths (3 T and 1.5 T) and automated analysis is currently less accurate than manual counting. Five studies were included for the proportional meta-analysis. From the analysis, a proportion of 45% of lesions having the CVS was suggested given that the findings that the weighted proportion was 46.4% (95% confidence interval [CI]: of 40.3%-52.6%) with low heterogeneity (I² = 0.0%; p=0.5).

CONCLUSION

Although the CVS is a clinically relevant and viable sign, further work is needed to integrate this into the existing diagnostic criteria. As manual determination is a time-consuming process, the development of automated methods will be beneficial. With improvements in computational imaging techniques, the CVS will have an important role in the diagnosis and differentiation of MS.

SWAN-Venule: An Optimized MRI Technique to Detect the Central Vein Sign in MS Plaques

BACKGROUND AND PURPOSE

Multiple sclerosis lesions develop around small veins that are radiologically described as the so-called central vein sign. With 7T MR imaging and magnetic susceptibility-based sequences, the central vein sign has been observed in 80%-100% of MS lesions in patients' brains. However, a lower proportion ∼50% has been reported at 3T using susceptibility-weighted angiography (SWAN). Our aim was to assess a modified version of SWAN optimized at 3T for sensitive detection of the central vein sign.

MATERIALS AND METHODS

Thirty subjects with MS were scanned on a 3T clinical MR imaging system. 3D T2-weighted FLAIR and optimized 3D SWAN called SWAN-venule, were acquired after injection of a gadolinium-based contrast agent. Patients showing >3 focal white matter lesions were included. The central vein sign was recorded by 2 trained raters on SWAN-venule images in the supratentorial brain.

RESULTS

Twenty patients showing >3 white matter lesions were included. A total of 380 white matter lesions (135 periventricular, 144 deep white matter, and 101 juxtacortical) seen on both FLAIR and SWAN-venule images were analyzed. Overall, the central vein sign was detected in 86% of the white matter lesions (periventricular, 89%; deep white matter, 95%; and juxtacortical, 78%).

CONCLUSIONS

The SWAN-venule technique is an optimized MR imaging sequence for highly sensitive detection of the central vein sign in MS brain lesions. This work will facilitate the validation and integration of the central vein sign to increase the diagnostic certainty of MS and further prevent misdiagnosis in clinical practice.

Seropositive neuromyelitis optica spectrum disorder in Emirati patients: A case series

OBJECTIVE

To describe clinical and radiological characteristics of seropositive neuromyelitis optica (NMO) in Emirati patients. While epidemiology of seropositive NMO in Abu Dhabi has been reported in a previous paper, its clinical and MRI profiles among Emirati patients have not been previously fully investigated.

METHODS

In our case series, we describe clinical and MRI characteristics of 5 Emirati patients with NMO, consecutively admitted at Cleveland Clinic Abu Dhabi, a major tertiary hospital in Abu Dhabi, United Arab Emirates.

RESULTS

Patients were all females, mean age of onset (SD) was 41 (11) years, and 67% had autoimmune comorbidities. Most patients initially presented with acute myelitis (80%) while 20% got optic neuritis. Mean (SD) number of further relapses after onset was 3 (1) and mean (SD) disease duration was 12 (11) years. At MRI, apparent longitudinal extensive transverse myelitis was present in all patients affecting mostly the central gray matter of the cervical cord but extending as well to the thoracic portion. Furthermore, seropositive NMO related brain lesions were also observed.

CONCLUSIONS

Our work provides valuable information regarding seropositive NMO with the potential to increase recognition of this disorder in Abu Dhabi and confirms NMO findings described in the other populations with this disorder. Further research is needed to advance clinical and MRI characterization of seronegative NMO in the region.

The "Central Vein Sign" on T2*-weighted Images as a Diagnostic Tool in Multiple Sclerosis: A Systematic Review and Meta-analysis using Individual Patient Data

We aimed to evaluate the pooled incidence of central vein sign on T2*-weighted images from patients with multiple sclerosis (MS), and to determine the diagnostic performance of this central vein sign for differentiating MS from other white matter lesions and provide an optimal cut-off value. A computerized systematic search of the literature in PUBMED and EMBASE was conducted up to December 14, 2018. Original articles investigating central vein sign on T2*-weighted images of patients with MS were selected. The pooled incidence was obtained using random-effects model. The pooled sensitivity and specificity were obtained using a bivariate random-effects model. An optimal cut-off value for the proportion of lesions with a central vein sign was calculated from those studies providing individual patient data. Twenty-one eligible articles covering 501 patients with MS were included. The pooled incidence of central vein sign at the level of individual lesion in patients with MS was 74% (95% CI, 65-82%). The pooled sensitivity and pooled specificity for the diagnostic performance of the central vein sign were 98% (95% CI, 92-100%) and 97% (95% CI, 91-99%), respectively. The area under the HSROC curve was 1.00 (95% CI, 0.99-1.00). The optimal cut-off value for the proportion of lesions with a central vein sign was found to be 45%. Although various T2*-weighted images have been used across studies, the current evidence supports the use of the central vein sign on T2*-weighted images to differentiate MS from other white matter lesions.

Characterization of Contrast-Enhancing and Non-contrast-enhancing Multiple Sclerosis Lesions Using Susceptibility-Weighted Imaging

Susceptibility-weighted magnetic resonance imaging (MRI) (SWI) offers additional information on conventional MRI contrasts. Central veins can be identified within lesions, and recently, it has been suggested that multiple sclerosis (MS) lesions with slowly expanding demyelination, so-called smoldering lesions, can be identified by a phase rim surrounding the lesion. We analyzed post-contrast SWI in regard to intrinsic lesion characteristics in a cohort of MS patients. A total of 294 MS patients were evaluated using a 3-T MRI. A comprehensive MRI protocol was used including post-contrast SWI. Lesions of at least 5 mm in size were analyzed on conventional MRI and SWI with a structured reporting scheme with a focus on SWI lesion characteristics. A total of 1,323 lesions were analyzed: 1,246/1,323 (94%) were non-enhancing and 77/1,323 (6%) were contrast-enhancing (CE) lesions. In CE lesions, the following patterns were seen: contrast enhancement was nodular in 34/77, ring-shaped enhancement was present in 33/77, and areas of peripheral enhancement were present in 10/77. In CE lesions, an association with central veins was found in 38/77 (50%). In 75/1,246 (6%) non-enhancing lesions, a central dark dot in keeping with a central vein was seen, whereas 162/1,246 (13%) showed peripheral hypointense dots/rims, 199/1,246 (16%) showed scattered hypointense dots mainly within the lesion area, and in 374/1,246 (30%), no SWI hypointensity was detected. Furthermore, 436/1,246 (35%) lesions showed isointensity to the surrounding tissue and were not visible on SWI. SWI is able to offer additional aspects of MS pathology also when used after the application of a contrast agent. Veins connected to lesions, a potentially useful marker in the differential diagnosis of MS, were seen in about 50% of enhancing lesions. Susceptibility artifacts, suggested to mark the presence of myelin-laden macrophages and smoldering inflammation, were visible in 28% of lesions as hypointense dots in and in the periphery of the lesion. Given those results, SWI may provide practical useful additional information in the evaluation of the lesion status in MS patients.

The "central vein sign" in patients with diagnostic "red flags" for multiple sclerosis: A prospective multicenter 3T study

BACKGROUND

The central vein sign (CVS) has been shown to help in the differential diagnosis of multiple sclerosis (MS), but most prior studies are retrospective.

OBJECTIVES

To prospectively assess the diagnostic predictive value of the CVS in diagnostically difficult cases.

METHODS

In this prospective multicenter study, 51 patients with suspected MS who had clinical, imaging, or laboratory "red flags" (i.e. features atypical for MS) underwent 3T fluid-attenuated inversion recovery (FLAIR*) magnetic resonance imaging (MRI) for CVS assessment. After the diagnostic work-up, expert clinicians blinded to the results of the CVS assessment came to a clinical diagnosis. The value of the CVS to prospectively predict an MS diagnosis was assessed.

RESULTS

Of the 39 patients who received a clinical diagnosis by the end of the study, 27 had MS and 12 received a non-MS diagnosis that included systemic lupus erythematosus, sarcoidosis, migraine, Sjögren disease, SPG4-spastic-paraparesis, neuromyelitis optica, and Susac syndrome. The percentage of perivenular lesions was higher in MS (median = 86%) compared to non-MS (median = 21%; p < 0.0001) patients. A 40% perivenular lesion cutoff was associated with 97% accuracy and a 96% positive/100% negative predictive value.

CONCLUSION

The CVS detected on 3T FLAIR* images can accurately predict an MS diagnosis in patients suspected to have MS, but with atypical clinical, laboratory, and imaging features.

Paediatric multiple sclerosis: a new era in diagnosis and treatment

Multiple sclerosis is a chronic immune-mediated demyelinating disease of the central nervous system. The diagnosis of multiple sclerosis in children, as in adults, requires evidence of dissemination of inflammatory activity in more than one location in the central nervous system (dissemination in space) and recurrent disease over time (dissemination in time). The identification of myelin oligodendrocyte glycoprotein antibodies (MOG-Ab) and aquaporin-A antibodies (AQP4-Ab), and the subsequent discovery of their pathogenic mechanisms, have led to a shift in the classification of relapsing demyelinating syndromes. This is reflected in the 2017 revised criteria for the diagnosis of multiple sclerosis, which emphasizes the exclusion of multiple sclerosis mimics and aims to enable earlier diagnosis and thus treatment initiation. The long-term efficacy of individual therapies initiated in children with multiple sclerosis is hard to evaluate, owing to the small numbers of patients who have the disease, the relatively high number of patients who switch therapy, and the need for long follow-up studies. Nevertheless, an improvement in prognosis with a globally reduced annual relapse rate in children with multiple sclerosis is now observed compared with the pretreatment era, indicating a possible long-term effect of therapies. Given the higher relapse rate in children compared with adults, and the impact multiple sclerosis has on cognition in the developing brain, there is a question whether rapid escalation or potent agents should be used in children, while the short- and long-term safety profiles of these drugs are being established. With the results of the first randomized controlled trial of fingolimod versus interferon-β1a in paediatric multiple sclerosis published in 2018 and several clinical trials underway, there is hope for further progress in the field of paediatric multiple sclerosis. WHAT THIS PAPER ADDS: Early and accurate diagnosis of multiple sclerosis is crucial. The discovery of antibody-mediated demyelination has changed the diagnosis and management of relapsing demyelination syndromes. Traditional escalation therapy is being challenged by induction therapy.

Advances in brain imaging in multiple sclerosis

Brain imaging is increasingly used to support clinicians in diagnosing multiple sclerosis (MS) and monitoring its progression. However, the role of magnetic resonance imaging (MRI) in MS goes far beyond its clinical application. Indeed, advanced imaging techniques have helped to detect different components of MS pathogenesis in vivo, which is now considered a heterogeneous process characterized by widespread damage of the central nervous system, rather than multifocal demyelination of white matter. Recently, MRI biomarkers more sensitive to disease activity than clinical disability outcome measures, have been used to monitor response to anti-inflammatory agents in patients with relapsing-remitting MS. Similarly, MRI markers of neurodegeneration exhibit the potential as primary and secondary outcomes in clinical trials for progressive phenotypes. This review will summarize recent advances in brain neuroimaging in MS from the research setting to clinical applications.

Three-dimensional MRI sequences in MS diagnosis and research

The most recent guidelines for magnetic resonance imaging (MRI) in multiple sclerosis (MS) recommend three-dimensional (3D) MRI sequences over their two-dimensional (2D) counterparts. This development has been made possible by advances in MRI scanner hardware and software. In this article, we review the 3D versions of conventional sequences, including T1-weighted, T2-weighted and fluid-attenuated inversion recovery (FLAIR), as well as more advanced scans, including double inversion recovery (DIR), FLAIR2, FLAIR*, phase-sensitive inversion recovery, and susceptibility weighted imaging (SWI).

The Central Vein Sign in Radiologically Isolated Syndrome

BACKGROUND AND PURPOSE

Radiologically isolated syndrome describes asymptomatic individuals with incidental radiologic abnormalities suggestive of multiple sclerosis. Recent studies have demonstrated that >40% of white matter lesions in MS (and often substantially more) have visible central veins on MR imaging. This "central vein sign" reflects perivenous inflammatory demyelination and can assist in differentiating MS from other white matter disorders. We therefore hypothesized that >40% of white matter lesions in cases of radiologically isolated syndrome would show the central vein sign.

MATERIALS AND METHODS

We recruited 20 participants diagnosed with radiologically isolated syndrome after evaluation by a neurologist. We performed 3T MR imaging of the brain and cervical spinal cord. White matter lesions were analyzed for the central vein sign.

RESULTS

Of 391 total white matter lesions, 292 (75%) demonstrated the central vein sign (central vein sign+). The median proportion of central vein sign+ lesions per case was 87% (range, 29%-100%). When the "40% rule" that has been proposed to distinguish MS from other disorders was applied, of 20 participants, 18 cases of radiologically isolated syndrome (90%) had ≥40% central vein sign+ lesions (range, 55%-100%). Two participants (10%) had <40% central vein sign+ lesions (29% and 31%). When the simpler "rule of 6" was applied, 19 participants (95%) met these criteria. In multivariable models, the number of spinal cord and infratentorial lesions was associated with a higher proportion of central vein sign+ lesions (P = .002; P = .06, respectively).

CONCLUSIONS

Most cases of radiologically isolated syndrome had a high proportion of central vein sign+ lesions, suggesting that lesions in these individuals reflect perivenous inflammatory demyelination. Moreover, we found correlations between the proportion of central vein sign+ lesions and spinal cord lesions, a known risk factor for radiologically isolated syndrome progressing to MS. These findings raise the possibility, testable prospectively, that the central vein sign may have prognostic value in distinguishing patients with radiologically isolated syndrome at risk of developing clinical MS from those with white matter lesions of other etiologies.

Iron related changes in MS lesions and their validity to characterize MS lesion types and dynamics with Ultra-high field magnetic resonance imaging

Iron accumulates with age in the normal human brain. This process is altered at several levels in the brain of multiple sclerosis (MS) patients. Since iron is mainly stored in oligodendrocytes and myelin in the normal brain, its liberation in demyelinating lesions may amplify tissue damage in demyelinating lesions and its uptake in macrophages and microglia may help to more precisely define activity stages of the lesions. In addition, glia cells change their iron import, export and storage properties in MS lesions, which is reflected by alterations in the expression of iron transport molecules. Changes of iron distribution in the brain can be reliably detected by MRI, particularly upon application of Ultra‐high magnetic field (7 Tesla). Iron‐sensitive MRI allows to more accurately distinguish the lesions in MS from those in other inflammatory brain diseases, to visualize a subset of slowly expanding lesions in the progressive stage of MS and to increase the sensitivity for lesion detection in the gray matter, such as the cerebral cortex or deep gray matter nuclei.

Predicting conversion from clinically isolated syndrome to multiple sclerosis-An imaging-based machine learning approach

Magnetic resonance imaging (MRI) scans play a pivotal role in the evaluation of patients presenting with a clinically isolated syndrome (CIS), as these may depict brain lesions suggestive of an inflammatory cause. We hypothesized that it is possible to predict the conversion from CIS to multiple sclerosis (MS) based on the baseline MRI scan by studying image features of these lesions.

We analyzed 84 patients diagnosed with CIS from a prospective observational single center cohort. The patients were followed up for at least three years. Conversion to MS was defined according to the 2010 McDonald criteria. Brain lesions were segmented based on 3D FLAIR and 3D T1 images. We generated brain lesion masks by a computer assisted manual segmentation. We also generated a set of automated segmentations using the Lesion Segmentation Toolbox for SPM to assess the influence of different segmentation methods. Shape and brightness features were automatically calculated from the segmented masks and used as input data to train an oblique random forest classifier. Prediction accuracies of the resulting model were validated through a three-fold cross-validation.

Conversion from CIS to MS occurred in 66 of 84 patients (79%). The conversion or non-conversion was predicted correctly in 71 patients based on shape features derived from the computer assisted manual segmentation masks (84.5% accuracy). This predictor was more accurate than predicting conversion using dissemination in space at baseline according to the 2010 McDonald criteria (75% accuracy). While shape features strongly contributed to the accuracy of the predictor, including intensity features did not further improve performance.

As patients who convert to definite MS benefit from early treatment, an early classification model is highly desirable. Our study shows that shape parameters of lesions can contribute to predicting the future course of CIS patients more accurately.

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A random forest tool can help to identify patients who convert from clinical isolated syndrome into multiple sclerosis (MS).

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The classifier is driven by shape features of lesions in the first MR scan.

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The found shape features reflect the typical ovoid growth of MS lesions.

The MRI central vein marker; differentiating PPMS from RRMS and ischemic SVD

Objective

To determine whether the assessment of brain white matter lesion (WML) central veins differentiate patients with primary progressive MS (PPMS) from relapsing-remitting MS (RRMS) and ischemic small vessel disease (SVD) using 3T MRI.

Methods

In this cross-sectional study, 71 patients with PPMS, RRMS, and SVD were imaged using a T2*-weighted sequence. Two blinded raters identified the total number of WMLs, proportion of WMLs in periventricular, deep white matter (DWM) and juxtacortical regions, and proportion of WMLs with central veins in all patient groups. The proportions were compared between disease groups, including effect sizes. MS or SVD was categorized using a threshold of ≥40% WMLs with central veins as indicative of MS. Interrater and intrarater reproducibility was calculated.

Results

The mean proportion of WMLs with central veins was 68.4% in PPMS, 74.3% in RRMS, and 4.7% in SVD. The difference in proportions between PPMS and SVD groups was significant (p < 0.0005; effect size: 3.8) but not significant between MS subtypes (p = 0.3; effect size: 0.29). Distribution of WMLs was similar across both MS groups, but despite SVD patients having more DWM lesions than PPMS patients, proportions of WMLs with central veins remained low (2.75% in SVD; 62.5% in PPMS). Interrater and intrarater reproducibility comparing proportions of WMLs with central veins across all patients was 0.86 and 0.90, respectively. Level of agreement between the proportion of WML central veins and established diagnosis was 0.84 and 0.82 for each rater.

Conclusions

WML central veins could be used to differentiate PPMS from SVD but not between MS subtypes.

Morphology-Specific Discrimination between MS White Matter Lesions and Benign White Matter Hyperintensities Using Ultra-High-Field MRI

BACKGROUND AND PURPOSE

Recently published North American Imaging in Multiple Sclerosis guidelines call for derivation of a specific radiologic definition of MS WM lesions and mimics. The purpose of this study was to use SWI and magnetization-prepared FLAIR images for sensitive differentiation of MS from benign WM lesions using the morphologic characteristics of WM lesions.

MATERIALS AND METHODS

Seventeen patients with relapsing-remitting MS and 18 healthy control subjects were enrolled retrospectively. For each subject, FLAIR and multiecho gradient-echo images were acquired using 7T MR imaging. Optimized postprocessing was used to generate single-slice SWI of cerebral veins. SWI/FLAIR images were registered, and 3 trained readers performed lesion assessment. Morphology, location of lesions, and the time required for assessment were recorded. Analyses were performed on 3 different pools: 1) lesions of >3 mm, 2) nonconfluent lesions of >3 mm, and 3) nonconfluent lesions of >3 mm with no or a single central vein.

RESULTS

The SWI/FLAIR acquisition and processing protocol enabled effective assessment of central veins and hypointense rims in WM lesions. Assessment of nonconfluent lesions with ≥1 central vein enabled the most specific and sensitive differentiation of patients with MS from controls. A threshold of 67% perivenous WM lesions separated patients with MS from controls with a sensitivity of 94% and specificity of 100%. Lesion assessment took an average of 12 minutes 10 seconds and 4 minutes 33 seconds for patients with MS and control subjects, respectively.

CONCLUSIONS

Nonconfluent lesions of >3 mm with ≥1 central vein were the most sensitive and specific differentiators between patients with MS and control subjects.