Cerebral vein changes in relapsing-remitting multiple sclerosis demonstrated by three-dimensional enhanced T₂-weighted angiography at 3.0 T

An Overview of Venous Abnormalities Related to the Development of Lesions in Multiple Sclerosis

The etiology of multiple sclerosis (MS) is currently understood to be autoimmune. However, there is a long history and growing evidence for disrupted vasculature and flow within the disease pathology. A broad review of the literature related to vascular effects in MS revealed a suggestive role for abnormal flow in the medullary vein system. Evidence for venous involvement in multiple sclerosis dates back to the early pathological work by Charcot and Bourneville, in the mid-nineteenth century. Pioneering work by Adams in the 1980s demonstrated vasculitis within the walls of veins and venules proximal to active MS lesions. And more recently, magnetic resonance imaging (MRI) has been used to show manifestations of the central vein as a precursor to the development of new MS lesions, and high-resolution MRI using Ferumoxytol has been used to reveal the microvasculature that has previously only been demonstrated in cadaver brains. Both approaches may shed new light into the structural changes occurring in MS lesions. The material covered in this review shows that multiple pathophysiological events may occur sequentially, in parallel, or in a vicious circle which include: endothelial damage, venous collagenosis and fibrin deposition, loss of vessel compliance, venous hypertension, perfusion reduction followed by ischemia, medullary vein dilation and local vascular remodeling. We come to the conclusion that a potential source of MS lesions is due to locally disrupted flow which in turn leads to remodeling of the medullary veins followed by endothelial damage with the subsequent escape of glial cells, cytokines, etc. These ultimately lead to the cascade of inflammatory and demyelinating events which ensue in the course of the disease.

Optic radiations are thinner and show signs of iron deposition in patients with long-standing remitting-relapsing multiple sclerosis: an enhanced T2*-weighted angiography imaging study

Objective

This study aimed to investigate iron deposition and thickness and signal changes in optic radiation (OR) by enhanced T₂^*-weighted angiography imaging (ESWAN) in patients with relapsing-remitting multiple sclerosis (RRMS) with unilateral and bilateral lesions or no lesions.

Methods

Fifty-one RRMS patients (42 patients with a disease duration [DD] ≥ 2 years [group Mor], nine patients with a DD < 2 years [group Les]) and 51 healthy controls (group Con) underwent conventional magnetic resonance imaging (MRI) and ESWAN at 3.0 T. The mean phase value (MPV) of the OR was measured on the phase image, and thickness and signal changes of the OR were observed on the magnitude image.

Results

The average MPVs for the OR were 1,981.55 ± 7.75 in group Mor, 1,998.45 ± 2.01 in group Les, and 2,000.48 ± 5.53 in group Con. In group Mor, 28 patients with bilateral OR lesions showed bilateral OR thinning with a heterogeneous signal, and 14 patients with unilateral OR lesions showed ipsilateral OR thinning with a heterogeneous signal. In the remaining nine patients without OR lesions and in group Con, the bilateral OR had a normal appearance. In the patients, a negative correlation was found between DD and OR thickness and a positive correlation was found between MPV and OR thickness.

Conclusions

We confirmed iron deposition in the OR in the RRMS patients, and the OR thickness was lower in the patients than in the controls.

Key Points

• Enhanced T₂^*-weighted magnetic resonance angiography (ESWAN) provides new insights into multiple sclerosis (MS).

• Focal destruction of the optic radiation (OR) is detectable by ESWAN.

• Iron deposition in OR can be measured on ESWAN phase image in MS patients.

• OR thickness was lower in the patients than in the controls.

• Iron deposition and thickness changes of the OR are associated with disease duration.

Electronic supplementary material

The online version of this article (10.1007/s00330-018-5461-8) contains supplementary material, which is available to authorized users.

A Brain Region-Based Deep Medullary Veins Visual Score on Susceptibility Weighted Imaging

Cerebral venous collagenosis played a role in the pathogenesis of white matter hyperintensities (WMHs) through venous ischemia. Since pathological changes of veins from intramural stenosis to luminal occlusion is a dynamic process, we aimed to create a deep medullary veins (DMVs) visual grade on susceptibility-weighted images (SWI) and explore the relationship of DMVs and WMHs based on venous drainage regions. We reviewed clinical, laboratory and imaging data from 268 consecutive WMHs patients and 20 controls. SWI images were used to observe characteristics of DMVs and a brain region-based DMVs visual score was given by two experienced neuroradiologists. Fluid attenuated inversion recovery (FLAIR) images were used to calculate WMHs volume. Logistic-regression analysis and partial Pearson’s correlation analysis were used to examine the association between the DMVs score and WMHs volume. We found that the DMVs score was significantly higher in WMHs patients than in controls (p < 0.001). Increased DMVs score was independently associated with higher WMHs volume after adjusting for total cholesterol level and number of lacunes (p < 0.001). Particularly, DMVs scores were correlated with regional PVHs volumes in the same brain region most. The newly proposed DMVs grading method allows the clinician to monitor the course of DMVs disruption. Our findings of cerebral venous insufficiency in WMHs patients may help to elucidate the pathogenic mechanisms and progression of WMHs.

Quantification of Phase Values of Cerebral Microbleeds in Hypertensive Patients Using ESWAN MRI

PURPOSE

The presence of cerebral microbleeds (CMBs) may have predictive and diagnostic value for cerebrovascular diseases. The purpose of our study was to measure the phase values (PVs) of CMBs by phase maps.

METHODS

We retrospectively analyzed 75 patients with hypertension who had CMBs using enhanced T2*-weighted angiography (ESWAN). The PVs of CMBs were measured and documented. The mean PVs of CMBs were correlated with demographic features and the grade of white matter lesions for seven brain regions.

RESULTS

A total of 275 CMBs were found. Their mean PV was - 1.39 ± 0.29 radians. The mean PV of CMBs in seven brain regions was significantly lower than that of red nucleus and substantia nigra of healthy controls (P <  .05). The mean PV of CMBs in the basal ganglia gray matter was significantly lower than that of the brainstem, subcortical white matter, and cerebellum (P < 0.05). In subcortical white matter, the PVs were significantly lower in patients with hypertension < 10 years than for those patients with hypertension ≥ 10 years (P < 0.05). In basal ganglia gray matter, the PVs were significantly lower in men than in women (P < 0.05). There was no significant correlation between the PVs of CMBs and the demographic features addressed or the grade of white matter lesions.

CONCLUSIONS

Measurement of the PV of phase maps using ESWAN sequence provides quantitative information for detection of CMBs. The measurement data reported herein will provide a reference for a longitudinal study of CMBs in the future.