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Objective: The unspecific symptoms of neonatal stroke still challenge its bedside diagnosis. We studied the accuracy of routine electroencephalography (EEG) and simultaneously recorded somatosensory evoked potentials (EEG-SEP) for diagnosis and outcome prediction of neonatal stroke. Methods: We evaluated EEG and EEG-SEPs from a hospital cohort of 174 near-term neonates with suspected seizures or encephalopathy, 32 of whom were diagnosed with acute ischemic or hemorrhagic stroke in MRI. EEG was scored for background activity and seizures. SEPs were classified as present or absent. Developmental outcome of stroke survivors was evaluated from medical records at 8- to 18-months age. Results: The combination of continuous EEG and uni- or bilaterally absent SEP (n = 10) was exclusively seen in neonates with a middle cerebral artery (MCA) stroke (specificity 100%). Moreover, 80% of the neonates with this finding developed with cerebral palsy. Bilaterally present SEPs did not exclude stroke, but predicted favorable neuromotor outcome in stroke survivors (positive predictive value 95%). Conclusions: Absent SEP combined with continuous EEG background in near-term neonates indicates an MCA stroke and a high risk for cerebral palsy. Significance: EEG-SEP offers a bedside method for diagnostic screening and a reliable prediction of neuromotor outcome in neonates suspected of having a stroke. (C) 2019 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

highlights In 46 healthy newborns, activity from both the primary (SI) and secondary somatosensory cortices (SII) was detectable with magnetoencephalography to tactile stimulation of the contralateral index finger dur- ing quiet sleep (QS). No significant interhemispheric differences in the responses from SI or SII existed. Within the neonatal period (postmenstrual age (PMA) between 37 and 44 weeks) PMA, height, or gen- der did not significantly affect the latency or strength of the somatosensory evoked magnetic fields (SEFs). abstract Objective: To determine interhemispheric differences and effect of postmenstrual age (PMA), height, and gender on somatosensory evoked magnetic fields (SEFs) from the primary (SI) and secondary (SII) somatosensory cortices in healthy newborns. Methods: We recorded SEFs to stimulation of the contralateral index finger (right in 46 and left in 12) healthy fullterm newborns and analyzed the magnetic responses with equivalent current dipoles. Results: Activity from both the SI and SII was consistently detectable in the contralateral hemisphere of the newborns during quiet sleep. No significant interhemispheric differences existed in SI or SII response peak latencies, source strengths, or location (n = 8, quiet sleep). SI or SII response peak latency or source strength were not significantly affected by PMA, height, or gender. Conclusions: During the neonatal period (PMA 37-44 weeks), activity from the contralateral SI and SII can be reliably evaluated with MEG. The somatosensory responses are similar in the left and right hemi- spheres and no corrections for exact PMA, height, or gender are necessary for interpreting the results. However, the evaluation should be conducted in quiet sleep. Significance: The reproducibility of the magnetic SI and SII responses suggests clinical applicability of the presented MEG method.

Introduction Differential diagnostics and outcome prediction in newborns presenting with seizures or encephalopathy remain difficult in the bedside. The objectives of the present study were (i) to determine the accuracy of simultaneously recorded EEG and somatosensory evoked potentials (SEPs) in differentiating between hypoxic-ischemic encephalopathy (HIE) and stroke as the underlying etiology of neonatal seizures or encephalopathy and (ii) to determine the accuracy of EEG and SEPs and their combination for predicting outcome in newborns with HIE or stroke. Methods The study comprised of 133 newborns (gestational age > 34 weeks) that underwent a clinically indicated EEG and simultaneous SEPs in the acute phase of their illness. 102 of the newborns had HIE and 31 had stroke. EEG background was scored as continuous (sleep stages identifiable and EEG continuous at least in active sleep or awake state) or discontinuous (sleep stages not identifiable and EEG not continuous at any time during the recording). The SEPs were classified as bilaterally absent, unilaterally absent, or bilaterally present. Outcome was evaluated from medical records at approximately 1–1.5 years age. Death, cerebral palsy, severe mental retardation, and epilepsy were considered as unfavorable outcomes. Normal or mildly abnormal development (e.g. mild motor or language delay) were considered as favorable outcomes. Results The combinations of EEG and SEP abnormalities were indicative of etiology (HIE vs stroke) and predictive of outcome. If the EEG was discontinuous, the etiology was always HIE (33 newborns) regardless of SEPs. Furthermore, if the EEG was continuous, but SEPs were uni- (9 newborns) or bilaterally (1 newborn) absent, the etiology was always stroke. Normal SEPs and continuous EEG occurred in 69 newborns with HIE and 21 newborns with stroke, and hence in these newborns the distinction between the etiologies could not be made with the present EEG-SEP criteria. This combination was, however, highly predictive of a favorable outcome regardless of the etiology: The outcome was favorable in 67/69 of those HIE and 20/21 of those with stroke. On the contrary, bi- or unilaterally absent SEPs were associated with poor outcome in all newborns with HIE (22/22) and all but two newborns with stroke (8/10). Furthermore, in newborns with HIE, even if the EEG was discontinuous but SEPs were bilaterally present, the outcome was likely to be favorable (8/11 newborns). Conclusion EEG-SEP is useful in bedside differential diagnostics between HIE and stroke in newborns presenting with seizures or general signs of encephalopathy. Furthermore, EEG-SEP is accurate in outcome prediction in both etiologies.

Methods: An electrophysiological parameter measured by Magnetoencephalography was used to quantify an Intra-Cortical Connectivity (ICC) index focused on the primary somatosensory cortical areas (S1). Twenty one patients affected by mild (Extended Disability Scale Score, EDSS, mean 1,7 range 0-3,5) relapsing-remitting multiple sclerosis (RR-MS) in the remitting phase without clinically evident sensory impairment were evaluated. Three dimensional magnetic resonance imaging (3D-MRI) was used to quantify the lesion load, discriminating black hole (BH) and non-BH portions, normalized by individual brain volumes. Results: When matched with a control population, MS patients showed a reduced ICC, combined with the complete loss of the finger-dependent functional specialization in left S1 cortex. No association was found between ICC impairment and disease duration, or prolongation of the central sensory conduction time, evidence of spinal cord lesions and disease modifying therapy. The ICC index slightly correlated with the lesion load. Conclusion:A local index of intra-cortical connectivity in a circumscribed brain primary area was altered in mildly disabled RR-MS patients, also in absence of any impairment of central sensory conduction. It is concluded that the diffuse damage influencing the multi-nodal network subtending complex cerebral functions also affects intrinsic cortical connectivity. S1 ICC is proposed as a highly sensitive and simple-to-test functional index for the evaluation of the widespread cerebral damage in RR-MS.