Concomitant Analysis of Arterial, Venous, and CSF Flows using Phase-Contrast MRI: A Quantitative Comparison Between MS Patients and Healthy Controls

Abstract

Venous dysfunction has recently been hypothesized to contribute to the pathophysiology of multiple sclerosis (MS). 2D phasecontrast (PC) magnetic resonance imaging (MRI) is a non-invasive and innocuous technique enabling reliable quantification of cerebrospinal fluid (CSF) and blood flows in the same imaging session. We compared PC-MRI measurements of CSF, arterial and venous flows in MS patients to those from a normative cohort of healthy controls (HC). Nineteen MS patients underwent a standardized MR protocol for cerebral examination on a 3T system including Fast cine PC-MRI sequences with peripheral gating in four acquisition planes. Quantitative data were processed using a homemade software to extract CSF and blood flow regions of interest, animate flows, and calculate cervical and intracranial vascular flow curves during the cardiac cycle (CC). Results were compared with values obtained in 21 HC using multivariate analysis. Venous flow patterns were comparable in both groups without signs of reflux. Arterial flows (P ¼ 0.02) and cervical CSF dynamic oscillations (P ¼ 0.01) were decreased in MS patients. No significant differences in venous cerebral and cervical outflows were observed between groups, thereby contradicting the recently proposed theory of venous insufficiency. Unexpected decrease in arterial perfusion in MS patients warrants further correlation to volumetric measurements of the brain.

Lack of correlation between extracranial venous abnormalities and multiple sclerosis: a quantitative MRI study

“…Our results, when comparing patients with MS and HC without taking into account the possible effect of stenosis, are in line with most, 15,18,20,30 but not all, 19 previous studies. A possible explanation for this discrepancy may be the inclusion of patients with MS with progressive subtypes in the study by Sethi et al 19 Indeed, Feng et al 16 showed that the tAF of progressive forms were different from the tAF observed in RR-MS; thus, the normalization of IJV flows to tAF, which is different between the two subgroups, could explain this discrepancy.…”

“…Venous structures, owing to their anatomical properties, show a high intersubject variability, 15 even depending on the body position in which these structures are studied. 11 The presence of venous flow abnormalities in MS has been widely investigated during the last years.…”

“…15,16,18,19,25 Furthermore, to date, no studies were performed to investigate the possible relationships between venous flow abnormalities, internal jugular vein (IJV) stenosis and clinical outcomes. Thus, the aim of the present study was to perform a functional and anatomical evaluation of neck veins in patients with MS compared with a group of HC, correlating MRI flow measures and clinical variables, in order to elucidate a possible role of venous abnormalities in MS.…”

“…2 Among the potential factors that were related to MS, abnormal venous haemodynamics in the neck, including venous reflux and stenosis, has been hypothesized to be a feature of MS. [3][4][5][6] During the past few years, different studies were carried out to investigate the possible role of extracranial venous flow abnormalities in MS. These studies used different image modalities such as ultrasound 3,5,[7][8][9][10][11][12][13][14] and MRI, including contrast-enhanced MR venography (CE-MRV), phasecontrast MRI or time-of-flight sequences, 4,[15][16][17][18][19][20] and a combination of different imaging modalities. [21][22][23][24][25][26] These studies, however, yielded somewhat conflicting results, and the role of venous abnormalities in MS still remains in discussion.…”

Contrast-enhanced angiographic cone-beam computed tomography without pre-diluted contrast medium

“…We hypothesized that the degree of mean flow velocity (mFV) would reflect the degree of flow volume change. Normal ICA flow was assumed to be 270±35 cm 3 /min (4.5 ±0.6 cm 3 /s) [6]. TCD was performed before and after guiding catheter (7Fc envoy, Codman, Shurtleff, Inc.) insertion and before and after saline infusion using a pressure bag (300 mmHg).…”