Somatosensory evoked potentials and magnetic resonance imaging of the central nervous system in early multiple sclerosis

Abstract

Background Somatosensory evoked potentials (SSEP) are still broadly used, although not explicitly recommended, for the diagnostic work-up of suspected multiple sclerosis (MS). Objective To relate disability, SSEP, and lesions on T2-weighted magnetic resonance imaging (MRI) in patients with early MS. Methods In this monocentric retrospective study, we analyzed a cohort of patients with relapsing–remitting MS or clinically isolated syndrome, with a maximum disease duration of two years, as well as with available data on the score at the expanded disability status scale (EDSS), on SSEP, on whole spinal cord (SC) MRI, and on brain MRI. Results Complete data of 161 patients were available. Tibial nerve SSEP (tSSEP) were less frequently abnormal than SC MRI (22% vs. 68%, p < 0.001). However, higher EDSS scores were significantly associated with abnormal tSSEP (median, 2.0 vs. 1.0; p = 0.001) but not with abnormal SC MRI (i.e., at least one lesion; median, 1.5 vs. 1.5; p = 0.7). Of the 35 patients with abnormal tSSEP, 32 had lesions on SC MRI, and 2 had corresponding lesions on brain MRI. Conclusion Compared to tSSEP, SC MRI is the more sensitive diagnostic biomarker regarding SC involvement. In early MS, lesions as detectable by T2-weighted MRI are the main driver of abnormal tSSEP. However, tSSEP were more closely associated with disability, which is compatible with a potential role of tSSEP as prognostic biomarker in complementation of MRI.

Multiple Sclerosis in the Digital Health Age: Challenges and Opportunities - A Systematic Review

“…Along the same lines, when analysing resting state EEG, authors in 65 observed that PwMS have significantly lower posterior dominant rhythm and amplitude, which was negatively associated with disability. When analysing the correlation between evoked potentials in EEG and MS progression, authors in 48 revealed that SEP in EEG has a more pronounced correlation with MS disability, i.e. EDSS worsening, compared to MRI scans.…”

“…VEP , MEP 14,20,21,25,31,32,[38][39][40][41][42][43][44][45] , AEP 8,16,17,28 , SSEP 10,17,20,21,28,35,36,43,[46][47][48] • Longer VEP latencies correlate with retinal fibres are below norm 7,15,18,23,27,37 • Combination of EPs can predict MS progression after 20 years 11 , falls within one year, EDSS longitudinally 20,21,25,28,3146 , brain stem dysfunction 17 • Combination of EPs show stronger correlation with baseline EDSS than MRI white lesion burden 28 Oddball paradigm 49,63 • The delayed P300 peak reveals the inverse correlation between its amplitude and the mental fatigue level 49 • ERPs during the visual oddball task are correlated with processing speed at baseline in PwMS 63 Resting state 52,…”

“…In the same vein, the second most frequently investigated evoked potential in EEG is MEP, whose latency, amplitude and any detected abnormalities have extensively been analysed and investigated 14,20,21,25,31,32,[38][39][40][41][42][43][44][45] . Interestingly, SSEPs 10,17,20,21,28,35,36,43,[46][47][48] and AEPs 8,16,17,28 were less common and frequently used in the reviewed studies, but still offer, when combined with other evoked potentials, solid composite scores. Similarly, authors in 49,50 investigated and analysed evoked related potential (ERP) responses in MS patients by using the two-tone oddball paradigm.…”