P467: Combined neurophysiological and imaging assessment of motor cortical areas in EPM1A patients

Abstract

s of Poster Presentations / Clinical Neurophysiology 125, Supplement 1 (2014) S1–S339 S173 reviewed. A test was defined as successful if the patients’ habitual attacks were captured. Results: Ten patients were identified who had a repeat HVT following unsuccessful inpatient video-telemetry. In 4/10 patients repeat HVT captured their habitual episodes (40%). Conclusion: Investigation with repeat HVT captured the habitual attacks in 40% of patients compared to 8% with repeat inpatient VTs. These results suggest that if repeat telemetry is required, HVT is the most successful option to capture habitual attacks. Further work is needed to confirm diagnostic accuracy and utility of HVT considering parameters such as age and nature of disease (epileptic v. non-epileptic attacks). P467 Combined neurophysiological and imaging assessment of motor cortical areas in EPM1A patients E. Visani1, L. Canafoglia1, D. Rossi Sebastiano1, V. Contarino2, L. D’Incerti2, F. Panzica1, S. Franceschetti1 1Fondazione IRCCS Carlo Besta, Neurophysiology, Milan, Italy; 2Fondazione IRCCS Carlo Besta, Neuroradiology, Milan, Italy Question: To assess functional organization of the motor cortex in patients with cortical myoclonus due to Unverricht-Lundborg disease (EPM1A) using multimodal neurophysiologic and imaging approach. Methods: Seven healthy subjects and nine EPM1A patients were enrolled in the study. TMS-based mapping of primary motor cortex of the hand associated to real-time frameless neuronavigation system was performed. fMRI activation maps related to hand motor task was obtained. Cortical thickness (CTH) analysis were applied on T1-weighted 3D images. Results: Bilaterally resting motor threshold was significantly higher and mean amplitude of the motor evoked potentials was significantly lower in the patients with respect to healthy subjects. There were no differences between groups in the extension of the cortical representation of the ABP muscle, but bilaterally the centers of gravity (CoGs) of EPM1A patients (Fig. 1, filled circles) lied posteriorly than that of healthy subjects (Fig. 1, crossed circles). fMRI did not revealed significant differences between groups, although a slightly posterior localization of activated cluster was found in patients (Fig. 2A, red cluster) with respect to healthy subjects (Fig. 2A, blue cluster). CTH analysis revealed significant alterations in both precentral and paracentral areas bilaterally, resulting in a thinning of these areas in EPM1A patients (Fig. 2B).