MRI white matter lesion central veins in multiple sclerosis

This thesis focuses on the use of the Magnetic Resonance Imaging (MRI) white matter lesion (WML) central vein as a biomarker for multiple sclerosis (MS). MS remains a clinical diagnosis, with reliance on MRI to support the diagnosis. Misinterpretation of the MRI can lead to misdiagnoses of diseases that mimic MS. With the increase in disease modifying treatments, accurate and timely diagnosis is needed now more than ever. Using T2* weighted imaging at 3 Tesla (T) MRI, I explored different aspects of WML central veins in patients with relapsing-remitting (RRMS), primary progressive MS (PPMS), and ischaemic small vessel disease (SVD) including: (1) the effect of using different T2* weighted sequences; (2) how T2* and susceptibility weighted imaging (SWI) and fused imaging techniques such as fluid attenuated inversion recovery (FLAIR)-SWI affected the proportion of WML central veins and; (3) determining if WML central veins were as prevalent in patients with PPMS. Further objectives included: (4) attempting to determine if vascular risk factors altered the proportion of WML central veins in patients with MS and; (5) using statistical modelling to calculate a simple diagnostic rule using WML central veins to differentiate MS from SVD. The proportion of WMLs with central veins differed significantly between patients with MS and SVD. Variations of the T2* sequence altered the proportion of WMLs with central veins, but the difference between MS and SVD remained statistically significant. T2* and SWI allowed a higher proportion of WMLs with central veins to be detected, with T2* being just as accurate as FLAIR-SWI in allowing the diagnosis of MS or SVD. Patients with PPMS and RRMS have a similarly high proportion of WMLs with central veins. High sensitivity and specificity for the diagnosis of MS versus SVD can be achieved by identifying a subset of WMLs with central veins. WML central veins could be used as an MRI biomarker using T2* imaging at 3T to differentiate cases of diagnostic uncertainty with RRMS, PPMS and SVD. Application of this imaging technique to patients with diagnostic uncertainty in prospective studies needs to be studied along with refining a clinical diagnostic rule