Angelo Insola1, Vincenzo Di Lazzaro2, Giovanni Assenza3. 1. Neurophysiology Unit, CTO Hospital, Rome, Italy. 2. Neurology, Neurophysiology and Neurobiology Unit, Department of Medicine, Università Campus Bio-Medico di Roma, Rome, Italy. 3. Neurology, Neurophysiology and Neurobiology Unit, Department of Medicine, Università Campus Bio-Medico di Roma, Rome, Italy. Electronic address: g.assenza@unicampus.it.
Abstract
OBJECTIVE: The pathophysiology of epilepsia partialis continua (EPC) is still unclear, a thalamo-cortical circuit dysfunction has been hypothesized. The aim of present study is the functional evaluation of the thalamo-cortical network in EPC by means of the study of low- and high-frequency somatosensory evoked potentials (LF-SEP and HF-SEP). METHODS: Median LF-SEP and HF-SEP were recorded in 3 patients with EPC and in 2 patients with rolandic lesions without EPC (non-EPC). Recording electrodes were placed on P3, C3, F3 and P4, C4, F4 of scalp regions. HF-SEP were obtained by an offline 400-800 Hz filtering of P3-F3 and P4-F4 traces. RESULTS: In EPC patients, we found a significant suppression of post-synaptic HF-SEP burst and an amplitude reduction of the P24 wave of the LF-SEPs. Both these components are related to cortical inhibitory interneuron activity. HF-SEP and LF-SEP were normal in non-EPC patients. CONCLUSION: The different results obtained in patients with a rolandic lesion with and without EPC supports the hypothesis that EPC might be correlated to a dysfunction of gabaergic interneurons of a cortical sensory-motor network. SIGNIFICANCE: Our results might contribute to the understanding of the physiological basis of the cortical dysfunction causing epilepsia partialis continua.
OBJECTIVE: The pathophysiology of epilepsia partialis continua (EPC) is still unclear, a thalamo-cortical circuit dysfunction has been hypothesized. The aim of present study is the functional evaluation of the thalamo-cortical network in EPC by means of the study of low- and high-frequency somatosensory evoked potentials (LF-SEP and HF-SEP). METHODS: Median LF-SEP and HF-SEP were recorded in 3 patients with EPC and in 2 patients with rolandic lesions without EPC (non-EPC). Recording electrodes were placed on P3, C3, F3 and P4, C4, F4 of scalp regions. HF-SEP were obtained by an offline 400-800 Hz filtering of P3-F3 and P4-F4 traces. RESULTS: In EPC patients, we found a significant suppression of post-synaptic HF-SEP burst and an amplitude reduction of the P24 wave of the LF-SEPs. Both these components are related to cortical inhibitory interneuron activity. HF-SEP and LF-SEP were normal in non-EPC patients. CONCLUSION: The different results obtained in patients with a rolandic lesion with and without EPC supports the hypothesis that EPC might be correlated to a dysfunction of gabaergic interneurons of a cortical sensory-motor network. SIGNIFICANCE: Our results might contribute to the understanding of the physiological basis of the cortical dysfunction causing epilepsia partialis continua.
Authors: Giovanni Assenza; Cristofaro Nocerino; Mario Tombini; Giancarlo Di Gennaro; Alfredo D'Aniello; Alberto Verrotti; Alfonso Marrelli; Lorenzo Ricci; Jacopo Lanzone; Vincenzo Di Lazzaro; Leonilda Bilo; Antonietta Coppola Journal: Front Neurol Date: 2021-03-24 Impact factor: 4.003