Prospective combined brain and spinal cord MRI in clinically isolated syndromes and possible early multiple sclerosis: impact on dissemination in space and time

Background: The diagnosis of multiple sclerosis (MS) is based on dissemination in space (DIS) and time (DIT). The aim of the study was to assess the impact of spinal cord (SC) imaging on the evidence of DIS and DIT. Methods: Thirty‐five treatment‐naive patients with a first clinical symptom suggestive of MS were examined in a 2‐year prospective longitudinal follow‐up assessment. Brain and SC magnetic resonance imaging (MRI), Expanded Disability Status Scale and multiple sclerosis functional composite were analysed at baseline and after 1 and 2 years. Results: At study entry, 21 patients were classified as clinically isolated syndrome suggestive of MS (CIS) and 14 patients as possible early MS. SC lesions were detected at baseline in 14 CIS patients (67%, median: 1.0, enhancing 29%) and in 11 patients with possible early MS (79%, median: 2.0, enhancing 29%). DIS as depicted by additive SC imaging was detected in two additional individuals according to the revised versus the 2001 McDonald criteria. All patients with emerging cord lesions showed new brain lesions. Five individuals developed clinically asymptomatic cord lesions. Conclusions: Spinal cord abnormalities are frequent in CIS patients and in patients with possible early MS. SC imaging slightly improved the establishment of DIS, but had no impact on the evidence of DIT.