Magnetic Resonance Imaging in Primary Progressive Multiple Sclerosis Patients

Abstract

The recently developed effective treatment of primary progressive multiple sclerosis (PPMS) requires the accurate diagnosis of patients with this type of disease. Currently, the diagnosis of PPMS is based on the 2017 McDonald criteria, although the contribution of magnetic resonance imaging (MRI) to this process is fundamental. PPMS, one of the clinical types of MS, represents 10%–15% of all MS patients. Compared to relapsing–remitting MS (RRMS), PPMS differs in terms of pathology, clinical presentation and MRI features. Regarding conventional MRI, focal lesions on T2-weighted images and acute inflammatory lesions with contrast enhancement are less common in PPMS than in RRMS. On the other hand, MRI features of chronic inflammation, such as slowly evolving/expanding lesions (SELs) and leptomeningeal enhancement (LME), and brain and spinal cord atrophy are more common MRI characteristics in PPMS than RRMS. Nonconventional MRI also shows differences in subtle white and grey matter damage between PPMS and other clinical types of disease. In this review, we present separate diagnostic criteria, conventional and nonconventional MRI specificity for PPMS, which may support and simplify the diagnosis of this type of MS in daily clinical practice.

Peripheral Nerve Involvement at First Diagnosis of Multiple Sclerosis

“…Alternatively, high levels of CNS inflammation may cause nonspecific inflammation in peripheral nerves. In a broader sense, our results emphasize the broad spectrum of MS subtypes 25 …”

“…In a broader sense, our results emphasize the broad spectrum of MS subtypes. 25 Subtyping of neuroinflammatory diseases requires objective biomarkers with high sensitivity and specificity. T2-relaxometry and MRN have proven highly sensitive in detecting peripheral nerve pathologies of various etiologies [11][12][13][14] and were shown to be robust and reliable.…”

Diffusion-based structural connectivity patterns of multiple sclerosis phenotypes

“…By contrast, the PPMS phenotype differed less from CIS/RRMS, with alterations limited to bilateral frontal and right parietal connections, and with less extensive network changes than in SPMS, as suggested previously 33 . These findings are concordant with what is commonly observed in PPMS, and with the present results, where the burden of brain lesions is lower and atrophy predominates (Table 1) 34 . All in all, these results support the idea that these MS phenotypes have a continuum of pathological mechanisms underlying the disease course.…”

T2-fluid attenuated inversion recovery mismatch in tumefactive multiple sclerosis

“…Several advanced MRI techniques are under ongoing investigation for the evaluation of demyelinating disease (such as myelin water imaging and quantitative susceptibility mapping) that may serve as helpful differentiating markers 9,10 ; sadly their use is not yet clinically mature. It should be also remembered that T1 black holes are commonly seen in patients with high burden multiple sclerosis where plaques of severe myelin loss, axonal injury, and matrix destruction are present 11,12 and with the more recently described slowly expanding lesions where progressive decline in T1 intensity suggests ongoing neuro-axonal damage. 13,14 These T1 black holes are also typically T2 hyperintense and hypointense on FLAIR images ( Figure 5 ).…”