The Influence of Contrast-to-Noise Ratio on the Discrimination Between Cortical and Juxtacortical Lesions in Multiple Sclerosis.

OBJECTIVE: The objective of this study was to investigate the contrast-to-noise ratio (CNR) between cortical gray matter (GM) and subcortical white matter (WM) across the cortex in relation to the ability of 3-dimensional fluid attenuated inversion recovery and 3-dimensional double inversion recovery to distinguish between cortical lesions (CLs) and juxtacortical lesions (JCs). METHODS: A total of 38 multiple sclerosis patients underwent magnetic resonance imaging. Two neuroradiologists scored CLs and JCs on magnetic resonance imaging in 9 cerebral areas. Lesions were marked as nonclassifiable (NCs) when blurred WM-GM boundary leads to inaccuracy of their discrimination. The CNR between WM and GM (CNRWM-GM) was evaluated across the cortical areas. RESULTS: The CNRWM-GM varies across the cortex; the lower values were found in motor and sensorimotor areas where almost all NCs were localized. A strong negative correlation was found between CNRWM-GM and NCs. CONCLUSIONS: Discrimination between CLs and JCs is affected from the sharp visualization of the WM-GM boundary, which is directly related to CNRWM-GM.

Spinal cord lesions are frequently asymptomatic in relapsing-remitting multiple sclerosis: a retrospective MRI survey.

BACKGROUND: Spinal cord (SC) involvement correlates with poor prognosis in patients with multiple sclerosis (MS). Nevertheless, there is no consensus on the use of SC-MRI at follow-up, mainly because of the belief that SC lesions are nearly always symptomatic. OBJECTIVES: The aim of the present study was to investigate the frequency of asymptomatic SC combined unique activity (CUA, new/enlarging T2 or gadolinium-positive [Gd+] lesions) on MRI in a cohort of patients diagnosed with clinically isolated syndrome (CIS) or relapsing-remitting MS (RRMS). METHODS: We retrospectively investigated all scans showing SC-CUA in patients with CIS or RRMS referred to a single Italian MS centre. We determined whether they were symptomatic and whether they had associated brain radiological activity. RESULTS: In 340 SC-MRI scans with SC-CUA (230 patients), SC-CUA was asymptomatic in 31.2%; 12.1% of SC-CUA had neither clinical activity nor brain radiological activity (44.5% and 25.4%, respectively, considering only follow-up SC-CUA). At multivariate analysis asymptomatic SC-CUAs were associated with older age at onset (34.0 ± 10.37 vs 31.0 ± 9.99 years, p = 0.006), non-spinal onset (76.4 vs 47.4%, p < 0.001), lower EDSS score at MRI (1.8 ± 0.93 vs 2.4 ± 1.28, p = 0.001) and lower number of Gd+ SC lesions (0.1 ± 0.33 vs 0.3 ± 0.54, p = 0.04), compared to symptomatic SC-CUAs. CONCLUSIONS: A substantial proportion of our patients had SC-CUA without clinical symptoms and/or without concomitant brain MRI activity. In these patients, SC-CUA was the only sign of disease activity, suggesting that regular SC-MRI follow-up is required for reliable assessment of radiological activity and may improve the management of patients with MS.

Correlation between cortical lesions and cognitive impairment in multiple sclerosis.

OBJECTIVES: Gray matter (GM) damage is well known as a fundamental aspect of multiple sclerosis (MS). Above all, cortical lesions (CLs) burden, detectable at MRI with double inversion recovery (DIR) sequences, has been demonstrated to correlate with cognitive impairment (CI). The aim of this study was to investigate the role of CLs number in predicting CI in a cohort of patients with MS in a clinical practice setting. MATERIALS AND METHODS: Thirty consecutive patients with MS presenting CLs (CL+) at high-field (3.0 T) MRI 3D-DIR sequences and an even group of MS patients without CLs (CL-) as a control, were investigated with the Rao Brief Repeatable Battery of Neuropsychological Tests (BRB), Version A. Total and lobar CLs number were computed in CL+ patients. RESULTS: Among the sixty patients with MS enrolled, forty-seven (78.3%) had a relapsing-remitting course, while thirteen (21.7%) a progressive one, eleven secondary progressive, and two primary progressive. Compared to CL-, CL+ patients had a greater proportion of progressive forms (p = .03). The most affected region was the frontal lobe (73.3% of patients), followed by temporal and parietal ones (both 60.0%). Multivariate (logistic regression) analysis revealed a significant correlation between total CLs number and the presence of mild cognitive impairment defined as pathologic score in at least one BRB test (p = .04); it was also correlated with deficit at PASAT 3 (p = .05) and Stroop Test (p = .02). CONCLUSIONS: We confirmed CLs number, evaluated with a technique quite commonly available in clinical practice, as a predictive factor of CI in patients with MS, in order to improve the diagnosis and management of CI and monitor potential neuroprotective effects of therapies.