Lower Arterial Cross-Sectional Area of Carotid and Vertebral Arteries and Higher Frequency of Secondary Neck Vessels Are Associated with Multiple Sclerosis

Retinal Blood Vessel Analysis Using Optical Coherence Tomography (OCT) in Multiple Sclerosis

Background: Both greater retinal neurodegenerative pathology and greater cardiovascular burden are seen in people with multiple sclerosis (pwMS). Studies also describe multiple extracranial and intracranial vascular changes in pwMS. However, there have been few studies examining the neuroretinal vasculature in MS. Our aim is to determine differences in retinal vasculature between pwMS and healthy controls (HCs) and to determine the relationship between retinal nerve fiber layer (RNFL) thickness and retinal vasculature characteristics. Methods: A total of 167 pwMS and 48 HCs were scanned using optical coherence tomography (OCT). Earlier OCT scans were available for 101 pwMS and 35 HCs for an additional longitudinal analysis. Segmentation of retinal vasculature was performed in a blinded manner in MATLAB's optical coherence tomography segmentation and evaluation GUI (OCTSEG) software. Results: PwMS has fewer retinal blood vessels when compared to HCs (35.1 vs. 36.8, p = 0.017). Over the 5.4 year follow up, and when compared to HCs, pwMS has a significant decrease in number of retinal vessels (average loss of -3.7 p = 0.007). Moreover, the total vessel diameter in pwMS does not change when compared to the increase in vessel diameter in the HCs (0.06 vs. 0.3, p = 0.017). Only in pwMS is there an association between lower RNFL thickness and fewer retinal vessel number and smaller diameter (r = 0.191, p = 0.018 and r = 0.216, p = 0.007). Conclusions: Over 5 years, pwMS exhibit significant retinal vascular changes that are related to greater atrophy of the retinal layers.

Disability in multiple sclerosis is associated with vascular factors: An ultrasound study

BACKGROUND

Although multiple sclerosis (MS) is an immune-related disorder, pharmaceutical interventions targeting the immune system do not stop or reverse disability progression; the major challenge for this condition. Studies show that disability progression in MS is associated with vascular comorbidity and brain volume loss, indicating that a multi-targeted approach is required to prevent debilitation. The aim of the present study was to examine the associations between vascular ultrasound, disability, biochemistry and lifestyle data in people with MS (pwMS).

METHODS

Extracranial vascular ultrasound was performed on 51 pwMS and 25 age-matched controls. Sonographic interrogation determined carotid intima-media thickness (cIMT) and abnormal blood flow patterns. Disability was assessed using the Expanded Disability Status Scale (EDSS). Biochemical and lifestyle data were obtained for all participants.

RESULTS

The EDSS had a highly significant positive association with the cIMT of the right (r = 0.63; p = 0.001) and left (r = 0.49; p = 0.001) common carotid arteries and negative associations with the peak systolic blood flow velocity of the right vertebral artery (r = -0.42; p = 0.01) as well as end-diastolic velocity of the left internal carotid artery (r = -0.47; p = 0.01). These associations were significantly influenced by biochemical and lifestyle factors. Both cIMT and age showed significant associations with the EDSS. When cIMT was adjusted for age in a regression analysis, the association between the EDSS and the cIMT remained significant (p < 0.01), while the age association was reduced to being significant only at 10% (p = 0.06). There was no association between the use of MS medication and the EDSS (p = 0.56).

CONCLUSION

PwMS who had increased cIMT, a surrogate marker for atherosclerosis, and reduced carotid artery blood flow velocities were at risk for greater disability over and above the effect of aging. These findings provide important information for disease management and disability prevention in pwMS. Modification of diet and lifestyle may promote the unhindered flow of essential nutritional factors into the brain in pwMS.

Cerebral blood flow dependency on systemic arterial circulation in progressive multiple sclerosis

OBJECTIVES

To determine the relationship between systemic arterial blood flow (SABF) and cerebral perfusion measures in multiple sclerosis (MS) patients.

METHODS

Cerebral perfusion and SABF were assessed in 118 patients (75 clinically isolated syndrome (CIS)/relapsing-remitting MS and 43 progressive MS) through MRI examination with dynamic susceptibility contrast perfusion-weighted imaging (DSC-PWI) and Doppler ultrasound, respectively. Measures of mean transit time (MTT) and time-to-peak (TTP), measured in seconds, of the normal-appearing whole brain (NAWB) and gray matter (GM) were calculated. Blood flow through the bilateral common carotid and vertebral arteries (in mL/min) represents the SABF. Whole brain volume (WBV) and body mass index (BMI) were used as additional covariates.

RESULTS

Higher systolic blood pressure was associated with lower SABF (-0.256, p = 0.006). In the total MS sample, higher SABF was associated with shorter MTT and TTP of the NAWB (r = -0.256, p = 0.007 and r = -0.307, p = 0.001) and GM (r = -0.239, p = 0.012 and r = -0.3, p = 0.001). The SABF and TTP associations were driven by the PMS patients (r = -0.451, p = 0.004 and r = -0.451, p = 0.011). Only in PMS, SABF remained a significant predictor of NAWB (standardized β = -0.394, p = 0.022) and GM TTP (standardized β = -0.351, p = 0.037). MTT and TTP were significantly lower in patients within lower SABF quartiles when compared to the higher quartiles (age-, sex-, BMI-, and WBV-adjusted ANCOVA p < 0.025).

CONCLUSIONS

The direct relationship between systemic and cerebral blood flow seen in PMS patients may suggest failure in cerebrovascular reactivity mechanisms and insufficient perfusion control. Cerebral blood flow in PMS may be increasingly dependent on the SABF.

KEY POINTS

• In progressive multiple sclerosis (MS) patients, the systemic arterial blood flow (SABF) is associated with perfusion-based measure of time-to-peak (TTP) of the normal-appearing whole brain (r = -0.451, p = 0.004) and gray matter (r = -0.451, p = 0.004). • Cerebral blood flow in progressive MS is directly dependent on systemic arterial blood flow and may be influenced by blood pressure changes. • Neurovascular unit impairment may play an important role in MS pathophysiology and contribute towards greater clinical disability.

Lower cerebral arterial blood flow is associated with greater serum neurofilament light chain levels in multiple sclerosis patients

BACKGROUND

Hypoperfusion, vascular pathology, and cardiovascular risk factors are associated with disease severity in multiple sclerosis (MS). We aimed to assess relationships between cerebral arterial blood flow (CABF) and serum neurofilament light chain (sNfL), as neuronal damage biomarker.

METHODS AND MATERIALS

Total CABF was measured in 137 patients (86 clinically isolated syndrome (CIS)/relapsing-remitting (RR) and 51 progressive MS (PMS)) and 48 healthy controls (HCs) using Doppler ultrasound. sNfL was quantitated using single molecule assay (Simoa). 3.0T MRI examination allowed quantification of T2 lesion and whole-brain volume (WBV). Multiple linear regression models determined the sNfL associated with CABF after correction for demographic and MRI-derived variables.

RESULTS

After adjustment for age, sex and BMI, total CABF remained statistically significant and model comparisons showed that CABF explained additional 2.6% of the sNfL variance (β=-0.167, p=0.044). CABF also remained significant in a step-wise regression model (β=0.18, p=0.034) upon the inclusion of T2 lesion burden and WBV effects. Patients in the lowest CABF quartile (CABF≤761mL/min) had significantly higher sNfL (34.6pg/mL versus 23.9pg/mL, adjusted-p=0.042) when compared to the highest quartile (CABF≥1130mL/min).

CONCLUSION

Lower CABF is associated with increased sNfL in MS patients, highlighting the relationship between cerebral hypoperfusion and axonal pathology.

Vascular disease and multiple sclerosis: a post-mortem study exploring their relationships

Vascular comorbidities have a deleterious impact on multiple sclerosis clinical outcomes but it is unclear whether this is mediated by an excess of extracranial vascular disease (i.e. atherosclerosis) and/or of cerebral small vessel disease or worse multiple sclerosis pathology. To address these questions, a study using a unique post-mortem cohort wherein whole body autopsy reports and brain tissue were available for interrogation was established. Whole body autopsy reports were used to develop a global score of systemic vascular disease that included aorta and coronary artery atheroma, cardiac hypertensive disease, myocardial infarction and ischaemic stroke. The score was applied to 85 multiple sclerosis cases (46 females, age range 39 to 84 years, median 62.0 years) and 68 control cases. Post-mortem brain material from a subset of the multiple sclerosis (n = 42; age range 39-84 years, median 61.5 years) and control (n = 39) cases was selected for detailed neuropathological study. For each case, formalin-fixed paraffin-embedded tissue from the frontal and occipital white matter, basal ganglia and pons was used to obtain a global cerebral small vessel disease score that captured the presence and/or severity of arteriolosclerosis, periarteriolar space dilatation, haemosiderin leakage, microinfarcts, and microbleeds. The extent of multiple sclerosis-related pathology (focal demyelination and inflammation) was characterized in the multiple sclerosis cases. Regression models were used to investigate the influence of disease status on systemic vascular disease and cerebral small vessel disease scores and, in the multiple sclerosis group, the relationship between multiple sclerosis-related pathology and both vascular scores. We show that: (i) systemic cardiovascular burden, and specifically atherosclerosis, is lower and cerebral small vessel disease is higher in multiple sclerosis cases that die at younger ages compared with control subjects; (ii) the association between systemic vascular disease and cerebral small vessel disease is stronger in patients with multiple sclerosis compared with control subjects; and (iii) periarteriolar changes, including periarteriolar space dilatation, haemosiderin deposition and inflammation, are key features of multiple sclerosis pathology outside the classic demyelinating lesion. Our data argue against a common primary trigger for atherosclerosis and multiple sclerosis but suggest that an excess burden of cerebral small vessel disease in multiple sclerosis may explain the link between vascular comorbidity and accelerated irreversibility disability.

High density lipoprotein cholesterol and apolipoprotein A-I are associated with greater cerebral perfusion in multiple sclerosis

BACKGROUND

The pathophysiological mechanisms underlying the associations of multiple sclerosis (MS) neurodegeneration serum cholesterol profiles is currently unknown.

OBJECTIVE

To determine associations between lipid profile measures and cerebral perfusion-based indices in MS patients.

METHODS

Seventy-seven MS patients underwent 3 T MRI. Cerebral blood volume (CBV), time-to-peak (TTP) and mean transit time (MTT) measures were computed from dynamic susceptibility contrast (DSC) perfusion-weighted imaging (PWI) for normal-appearing brain tissue (NABT), GM, cortex, deep gray matter (DGM) and thalamus. Total cholesterol, low and high-density lipoprotein cholesterol (LDL-C and HDL-C) and the apolipoproteins (Apo), ApoA-I, ApoA-II, ApoB, ApoC-II and ApoE levels were measured in plasma. Age and body mass index (BMI)-adjusted correlations were used to assess the associations between PWI and lipid profile measures.

RESULTS

Higher HDL-C levels were associated with shorter MTT, which are indicative of greater perfusion, in NABT (p = 0.012), NAWM (p = 0.021), GM (p = 0.009), cortex (p = 0.014), DGM p = 0.015; and thalamus p = 0.015). The HDL-C-associated apolipoproteins, ApoA-I and ApoA-II, were associated with shorter MTT of the same brain regions (all p < 0.028). HDL-C and ApoA-I levels were also associated with shorter TTP, indicative of faster cerebral blood delivery. ApoC-II was associated with lower nCBV of the GM and cortex (p = 0.035 and p = 0.014, respectively).

CONCLUSION

The HDL pathway is associated with better global brain perfusion and faster cerebral blood delivery as measured by shorter MTT and TTP, respectively. ApoC-II may be associated with lower cortical and DGM perfusion.

Serum Neurofilament Light Chain Levels are Associated with Lower Thalamic Perfusion in Multiple Sclerosis

Both perfusion-weighted imaging (PWI) measures and serum neurofilament light (sNfL) chain levels have been independently associated with disability in multiple sclerosis (MS) patients. This study aimed to determine whether these measures are correlated to each other or independently describe different MS processes. For this purpose, 3T MRI dynamic susceptibility contrast (DSC)–PWI and single-molecule assay (Simoa)-based sNfL methods were utilized when investigating 86 MS patients. The perfusion measures of mean transit time (MTT), cerebral blood volume (CBV), and cerebral blood flow (CBF) were derived for the normal-appearing whole brain (NAWB), the normal-appearing white matter (NAWM), the gray matter (GM), the deep GM (DGM), and the thalamus. The normalized CBV and CBF (nCBV and nCBV) were calculated by dividing by the corresponding NAWM measure. Age- and sex-adjusted linear regression models were used to determine associations between the DSC–PWI and sNfL results. False discovery rate (FDR)-adjusted p-values < 0.05 were considered statistically significant. A greater age and thalamic MTT were independently associated with higher sNfL levels (p < 0.001 and p = 0.011) and explained 36.9% of sNfL level variance. NAWM MTT association with sNfL levels did not survive the FDR correction. In similar models, a lower thalamic nCBF and nCBV were both associated with greater sNfL levels (p < 0.001 and p = 0.022), explaining 37.8% and 44.7% of the variance, respectively. In conclusion, higher sNfL levels were associated with lower thalamic perfusion.

BOLD signal within and around white matter lesions distinguishes multiple sclerosis and non-specific white matter disease: a three-dimensional approach

Multiple sclerosis (MS) diagnostic criteria are based upon clinical presentation and presence of white matter hyperintensities on two-dimensional magnetic resonance imaging (MRI) views. Such criteria, however, are prone to false-positive interpretations due to the presence of similar MRI findings in non-specific white matter disease (NSWMD) states such as migraine and microvascular disease. The coexistence of age-related changes has also been recognized in MS patients, and this comorbidity further poses a diagnostic challenge. In this study, we investigated the physiologic profiles within and around MS and NSWMD lesions and their ability to distinguish the two disease states. MS and NSWMD lesions were identified using three-dimensional (3D) T₂-FLAIR images and segmented using geodesic active contouring. A dual-echo functional MRI sequence permitted near-simultaneous measurement of blood-oxygen-level-dependent signal (BOLD) and cerebral blood flow (CBF). BOLD and CBF were calculated within lesions and in 3D concentric layers surrounding each lesion. BOLD slope, an indicator of lesion metabolic capacity, was calculated as the change in BOLD from a lesion through its surrounding perimeters. We observed sequential BOLD signal reductions from the lesion towards the perimeters for MS, while no such decreases were observed for NSWMD lesions. BOLD slope was significantly lower in MS compared to NSWM lesions, suggesting decreased metabolic activity in MS lesions. Furthermore, BOLD signal within and around lesions significantly distinguished MS and NSWMD lesions. These results suggest that this technique shows promise for clinical utility in distinguishing NSWMD or MS disease states and identifying NSWMD lesions occurring in MS patients.

Longitudinal analysis of cerebral aqueduct flow measures: multiple sclerosis flow changes driven by brain atrophy

Background

Several small cross-sectional studies have investigated cerebrospinal fluid (CSF) flow dynamics in multiple sclerosis (MS) patients and have reported mixed results. Currently, there are no longitudinal studies that investigate CSF dynamics in MS patients.

Objective

To determine longitudinal changes in CSF dynamics measured at the level of aqueduct of Sylvius (AoS) in MS patients and matched healthy controls (HCs).

Materials and methods

Forty (40) MS patients and 20 HCs underwent 3T MRI cine phase contrast imaging with velocity-encoded pulse-gated sequence at baseline and 5-year follow-up. For atrophy determination, MS patients underwent additional high-resolution 3D T1-weighted imaging. Measures of AoS cross-sectional area (CSA), average systolic and diastolic velocity peaks, maximal systolic and diastolic velocity peaks and average CSF flow rates were determined. Brain atrophy and ventricular CSF (vCSF) expansion rates were determined. Cross-sectional and longitudinal changes were derived by analysis of covariance (ANCOVA) and paired repeated tests. Confirmatory general linear models were also performed. False discovery rate (FDR)-corrected p-values lower than 0.05 were considered significant.

Results

The MS population demonstrated significant increase in maximal diastolic peak (from 7.23 to 7.86 cm/s, non-adjusted p = 0.037), diastolic peak flow rate (7.76 ml/min to 9.33 ml/min, non-adjusted p = 0.023) and AoS CSA (from 3.12 to 3.69 mm², adjusted p = 0.001). The only differentiator between MS patients and HCs was the greater AoS CSA (3.58 mm² vs. 2.57 mm², age- and sex-adjusted ANCOVA, p = 0.045). The AoS CSA change was associated with vCSF expansion rate (age- and sex-adjusted Spearman’s correlation r = 0.496, p = 0.019) and not with baseline nor change in maximal velocity. The expansion rate of the vCSF space explained an additional 23.8% of variance in change of AoS CSA variance when compared to age and sex alone (R² = 0.273, t = 2.557, standardized β = 0.51, and p = 0.019).

Conclusion

MS patients present with significant longitudinal AoS enlargement, potentially due to regional atrophy changes and ex-vacuo expansion of the aqueduct.

Decrease in Secondary Neck Vessels in Multiple Sclerosis: A 5-year Longitudinal Magnetic Resonance Angiography Study

BACKGROUND

Studies have previously shown greater arterial and venous extracranial vascular changes in persons with multiple sclerosis (PwMS) when compared to healthy controls (HCs).

OBJECTIVES

To determine the change in the number and size of secondary neck vessels in PwMS and HCs over a 5-year follow-up period.

METHODS

Both at baseline and follow-up, 83 PwMS and 25 HCs underwent magnetic resonance angiography (MRA) imaging and analysis. The number and cross-sectional area (CSA) of all secondary neck vessels (excluding the common/internal carotid, vertebral artery, and internal jugular vein) measured at levels from C2-T1 were determined by semi-automated edge detection/ contouring software. The longitudinal change in the number and CSA of the secondary neck vessels from the PwMS and HCs were analyzed by non-parametric Wilcoxon repeated measure. Benjamini-Hochberg procedure adjusted for false discovery rate (FDR).

RESULTS

For over 5 years, PwMS demonstrated a consistent longitudinal decrease in both the number of secondary neck vessels (Z-change between -3.3 and -5.4, q=0.001) and their CSA (Zchange between -2.9 and -5.2, q=0.004). On the contrary, the HCs did not demonstrate a significant longitudinal change in secondary neck vessels over the follow-up period. Due to the longitudinal decrease, the PwMS showed a lower number of secondary neck vessels when compared to HCs measured at follow-up (p<0.029, except for C4 with trending p=0.071). The PwMS changes were also corroborated within each MS phenotype.

CONCLUSION

PwMS demonstrate a significant mid-term decrease in the number and the size of the secondary neck vessels. The clinical relevance of these findings and the effect on intracranial blood flow are currently unknown.

Lifestyle-based modifiable risk factors in multiple sclerosis: review of experimental and clinical findings

Multiple sclerosis (MS) is a lifelong inflammatory and neurodegenerative disease influenced by multiple lifestyle-based factors. We provide a narrative review of the effects of modifiable risk factors that are identified as being associated with risk to develop MS and/or influencing the future clinical disease outcomes. The emerging data regarding the beneficial effects of diet modifications and exercise are further reviewed. In contrast, obesity and comorbid cardiovascular diseases are associated with increased MS susceptibility and worse disease progression. In addition, the potential influence of smoking, coffee and alcohol consumption on MS onset and disability development are discussed. Successful management of the modifiable risk factors may lead to better long-term outcomes and improve patients' quality of life. MS specialists should participate in educating and facilitating lifestyle-based modifications as part of their neurological consults.

Vascular aspects of multiple sclerosis: emphasis on perfusion and cardiovascular comorbidities

INTRODUCTION

Multiple sclerosis (MS) is a chronic inflammatory, demyelinating, and neurodegenerative disease of the central nervous system. Over the last two decades, more favorable MS long-term outcomes have contributed toward increase in prevalence of the aged MS population. Emergence of age-associated pathology, such as cardiovascular diseases, may interact with the MS pathophysiology and further contribute to disease progression. Areas covered: This review summarizes the cardiovascular involvement in MS pathology, its disease activity, and progression. The cardiovascular health, the presence of various cardiovascular diseases, and their effect on MS cognitive performance are further explored. In similar fashion, the emerging evidence of a higher incidence of extracranial arterial pathology and its association with brain MS pathology are discussed. Finally, the authors outline the methodologies behind specific perfusion magnetic resonance imaging (MRI) and ultrasound Doppler techniques, which allow measurement of disease-specific and age-specific vascular changes in the aging population and MS patients. Expert opinion: Cardiovascular pathology significantly contributes to worse clinical and MRI-derived disease outcomes in MS. Global and regional cerebral hypoperfusion may be associated with poorer physical and cognitive performance. Prevention, improved detection, and treatment of the cardiovascular-based pathology may improve the overall long-term health of MS patients.

Dietary and lifestyle factors in multiple sclerosis progression: results from a 5-year longitudinal MRI study

BACKGROUND

Evidence regarding the role, if any, of dietary and lifestyle factors in the pathogenesis of multiple sclerosis (MS) is poorly understood.

OBJECTIVE

To assess the effect of lifestyle-based risk factors linked to cardiovascular disease (CVD) on clinical and MRI-derived MS outcomes.

METHODS

The study enrolled 175 MS or clinically isolated syndrome (CIS) patients and 42 age- and sex-matched healthy controls (HCs) who were longitudinally followed for 5.5 years. The 20-year CVD risk was calculated by Healthy Heart Score (HHS) prediction model which includes age, smoking, body mass index, dietary intake, exercise, and alcohol consumption. Baseline and follow-up MRI scans were obtained and cross-sectional and longitudinal changes of T2-lesion volume (LV), whole brain volume (WBV), white matter volume (WMV), gray matter volume (GMV), and lateral ventricular volume (LVV) were calculated.

RESULTS

After correcting for disease duration, the baseline HHS values of the MS group were associated with baseline GMV (r_s = - 0.20, p = 0.01), and longitudinal LVV change (r_s = 0.19, p = 0.01). The association with LVV remained significant after adjusting for baseline LVV volumes (r_s = 0.2, p = 0.008) in MS patients. The diet component of the HHS was associated with the 5-year T2-LV accrual (r_s = - 0.191, p = 0.04) in MS. In the HC group, the HHS was associated with LVV (r_s = 0.58, p < 0.001), GMV (r_s = - 0.57, p < 0.001), WBV (r_s = - 0.55, p = 0.001), T2-LV (r_s = 0.41, p = 0.027), and WMV (r_s = - 0.38, p = 0.042). Additionally, the HC HHS was associated with the 5-year change in LVV (r_s = 0.54, p = 0.001) and in WBV (r_s = - 0.45, p = 0.011).

CONCLUSION

Lifestyle risk factors contribute to accelerated central brain atrophy in MS patients, whereas unhealthier diet is associated with MS lesion accrual. Despite the lower overall effect when compared to HCs, lifestyle-based modifications may still provide a beneficial effect on reducing brain atrophy in MS patients.

Lower total cerebral arterial flow contributes to cognitive performance in multiple sclerosis patients

BACKGROUND

The cognitive performance in multiple sclerosis (MS) patients declines with aging, longer disease duration, and possibly cardiovascular comorbidities.

OBJECTIVES

We investigated whether lower total cerebral arterial blood flow (CABF) measured at the level of the carotid and vertebral arteries may contribute to worse cognitive performance in 132 MS patients and 47 healthy controls.

METHODS

Total CABF was evaluated with extracranial Doppler, whereas structural T2-lesion volume (LV) and gray matter volume (GMV) were measured on 3T MRI. The cognitive performance was assessed by Symbol Digit Modalities Test (SDMT), Brief Visuospatial Memory Test-Revised (BVMT-R), and California Verbal Learning Test-Second Edition (CVLT-II). Analysis of covariance, partial correlation, and regression models were used to test the differences between study groups and cognition/CABF correlations. False discovery rate (FDR)-corrected (Benjamini-Hochberg) p-values (i.e. q-values) less than 0.05 were considered significant.

RESULTS

Association between lower total CABF and the lower cognitive performance was observed only in MS patients (r = 0.318, q < 0.001 and r = 0.244, q = 0.012 for SDMT and BVMT-R, respectively). Lower GMV, higher T2-LV, and CABF were significantly associated with poorer performance on the processing speed measure of SDMT (adjusted R² = 0.295, t-statistics = 2.538, standardized β = 0.203, and q = 0.020), but not with memory tests. Cognitively impaired MS patients had lower total CABF compared to cognitively preserved (884.5 vs 1020.2 mL/min, q = 0.008).

CONCLUSION

Cognitively impaired MS patients presented with lower total CABF. Altered CABF may be a result of reduced metabolic rate and might contribute to abnormal cognitive aging in MS.

Changes in expression profiles of internal jugular vein wall and plasma protein levels in multiple sclerosis

Background

Multiple sclerosis (MS) is an inflammatory, demyelinating and degenerative disorder of the central nervous system (CNS). Several observations support interactions between vascular and neurodegenerative mechanisms in multiple sclerosis (MS). To investigate the contribution of the extracranial venous compartment, we analysed expression profiles of internal jugular vein (IJV), which drains blood from CNS, and related plasma protein levels.

Methods

We studied a group of MS patients (n = 19), screened by echo-color Doppler and magnetic resonance venography, who underwent surgical reconstruction of IJV for chronic cerebrospinal venous insufficiency (CCSVI). Microarray-based transcriptome analysis was conducted on specimens of IJV wall from MS patients and from subjects undergoing carotid endarterectomy, as controls. Protein levels were determined by multiplex assay in: i) jugular and peripheral plasma from 17 MS/CCSVI patients; ii) peripheral plasma from 60 progressive MS patients, after repeated sampling and iii) healthy individuals.

Results

Of the differentially expressed genes (≥ 2 fold-change, multiple testing correction, P < 0.05), the immune-related CD86 (8.5 fold-change, P = 0.002) emerged among the up regulated genes (N = 409). Several genes encoding HOX transcription factors and histones potentially regulated by blood flow, were overexpressed. Smooth muscle contraction and cell adhesion processes emerged among down regulated genes (N = 515), including the neuronal cell adhesion L1CAM as top scorer (5 fold-change, P = 5 × 10^− 4).

Repeated measurements in jugular/peripheral plasma and overtime in peripheral plasma showed conserved individual plasma patterns for immune-inflammatory (CCL13, CCL18) and adhesion (NCAM1, VAP1, SELL) proteins, despite significant variations overtime (SELL P < 0.0001). Both age and MS disease phenotypes were determinants of VAP1 plasma levels.

Data supported cerebral related-mechanisms regulating ANGPT1 levels, which were remarkably lower in jugular plasma and correlated in repeated assays but not between jugular/peripheral compartments.

Conclusions

This study provides for the first time expression patterns of the IJV wall, suggesting signatures of altered vascular mRNA profiles in MS disease also independently from CCSVI. The combined transcriptome-protein analysis provides intriguing links between IJV wall transcript alteration and plasma protein expression, thus highlighting proteins of interest for MS pathophysiology.

Electronic supplementary material

The online version of this article (10.1186/s10020-018-0043-4) contains supplementary material, which is available to authorized users.

Five-Year Longitudinal Study of Neck Vessel Cross-Sectional Area in Multiple Sclerosis

BACKGROUND AND PURPOSE

Alterations of neck vessel cross-sectional area in multiple sclerosis have been reported. Our aim was to investigate the evolution of the neck vessel cross-sectional area in patients with MS and healthy controls during 5 years.

MATERIALS AND METHODS

Sixty-nine patients with MS (44 relapsing-remitting MS, 25 progressive MS) and 22 age- and sex-matched healthy controls were examined twice, 5 years apart, on a 3T MR imaging scanner using 2D neck MR angiography. Cross-sectional areas were computed for the common carotid/internal carotid arteries, vertebral arteries, and internal jugular veins for all slices between the C3 and C7 cervical levels. Longitudinal cross-sectional area differences at each cervical level and the whole-vessel course were tested within study groups and between patients with MS with and without cardiovascular disease using mixed-model analysis and the related-samples Wilcoxon singed rank test. The Benjamini-Hochberg procedure was performed to correct for multiple comparisons.

RESULTS

No significant cross-sectional area differences were seen between patients with MS and healthy controls at baseline or at follow-up. During the follow-up, significant cross-sectional area decrease was found in patients with MS for the common carotid artery-ICAs (C4: P = .048; C7: P = .005; whole vessel: P = .012), for vertebral arteries (C3: P = .028; C4: P = .028; C7: P = .028; whole vessel: P = .012), and for the internal jugular veins (C3: P = .014; C4: P = .008; C5: P = .010; C6: P = .010; C7: P = .008; whole vessel: P = .002). Patients with MS without cardiovascular disease had significantly greater change than patients with MS with cardiovascular disease for internal jugular veins at all levels.

CONCLUSIONS

For 5 years, patients with MS showed significant cross-sectional area decrease of all major neck vessels, regardless of the disease course and cardiovascular status.

Neck Vessel Cross-Sectional Area Measured with MRI: Scan-Rescan Reproducibility for Longitudinal Evaluations

BACKGROUND AND PURPOSE

The cross-sectional area (CSA) of common carotid arteries-internal carotid arteries (CCA-ICAs), vertebral arteries (VAs), and internal jugular veins (IJVs) is influenced by aging. However, the neck vessel CSA can be affected by other factors as well, including subject positioning, hydration, and respiration, especially in longitudinal studies. This study aimed to assess scan-rescan reproducibility of CCA-ICAs, VAs, and IJVs CSA measurements in order to evaluate their feasibility for longitudinal CSA assessments, and to apply the segmentation method on a longitudinal pilot dataset.

METHODS

Two set of 2-dimensional neck magnetic resonance angiography (MRA) images were acquired on a 3-T scanner from two separate datasets: 9 healthy individuals (HIs) were scanned 5 days apart (scan-rescan dataset) and 12 HIs were acquired 5 years apart (baseline-follow-up dataset). CCA-ICAs, VAs, and IJVs were segmented along the whole vessel length between C3 and C7 intervertebral spaces. Repeated measure analysis of covariance, adjusted for cervical level and sample, and Wilcoxon signed-rank sum test were used to assess the scan-rescan and baseline-follow-up CSA differences. Intraclass correlation coefficient (ICC) was also computed to evaluate scan-rescan reliability.

RESULTS

No significant CSA differences were found for the scan-rescan and baseline-follow-up CSA comparisons, using the whole vessel length or single cervical level measurements. ICC analysis showed good degree of scan-rescan reproducibility (considering whole vessel measures: ICC > .9, P-value < .001 for CCA-ICAs, ICC > .6, P-value < .001 for VAs, and ICC > .7, P-value < .001 for IJVs).

CONCLUSIONS

Scan-rescan reproducibility of CCA-ICAs, VAs, and IJVs CSA measurements is high, making longitudinal studies feasible.