Stereo-EEG ictal/interictal patterns and underlying pathologies. (November 2019)

• Record Type: Journal Article
• Authors: Di Giacomo, Roberta; Uribe-San-Martin, Reinaldo; Mai, Roberto; Francione, Stefano; Nobili, Lino; Sartori, Ivana; Gozzo, Francesca; Pelliccia, Veronica; Onofrj, Marco; Lo Russo, Giorgio; de Curtis, Marco; Tassi, Laura
• Is Part Of: Seizure. Volume 72(2019)
• Page Start: 54
• Page End: 60
• Publication Date: 2019-11
• Subjects: EZ epileptogenic zone -- FCD focal cortical dysplasia -- HS hippocampal sclerosis -- IZ irritative zone -- LVFA low-voltage fast activity -- LZ lesional zone -- MR magnetic resonance -- FA fast activity -- PMG polymicrogyria -- PNH periventricular nodular heterotopia -- RFSB Repetitive fast spikes bursts -- RSA rhythmic sharp activity -- Stereo-EEG stereo-electroencephalography -- SOZ seizure onset zone -- SEEG-SOZ stereo-EEG identified seizure onset zone -- SB Slow burst -- THC thermocoagulation; Stereo-EEG -- Seizure onset zone -- Epileptogenic zone -- Interictal activity -- Malformations of cortical development -- Epilepsy surgery; Epilepsy -- Periodicals; Epilepsy -- Periodicals; Seizures -- Periodicals; Épilepsie -- Périodiques; Electronic journals; Electronic journals; 616.853
• DOI: 10.1016/j.seizure.2019.10.001
• Languages: English
• ISSNs: 1059-1311

Abstract

Highlights: Five SEEG-SOZ patterns were identified. SEEG-SOZ pattern is linked to the pathology, it is often related to fast activity. Interictal and post-ictal activity was insufficient to circumscribe the SEEG-SOZ. Analysis of SEEG-SOZ patterns may clarify prognosis and improve surgical resection. Abstract: Purpose: To define Stereo-EEG (SEEG) ictal and interictal patterns associated with different pathologies in a cohort of patients with drug-resistant focal epilepsy. Methods: We retrospectively analyzed findings from 102 patient with epilepsy due to Polymicrogyria (PMG), Periventricular Nodular Heterotopia (PNH), Focal Cortical Dysplasia (FCD) type I, IIa, IIb and Hippocampal Sclerosis (HS). Ictal and interictal SEEG recordings were reviewed to describe Seizure Onset Zone (SEEG-SOZ) patterns and to define the Lesional and Irritative Zones. Results: Five SEEG-SOZ patterns were identified: significant associations were found between low-voltage fast activity and PMG and between repetitive fast spikes bursts and FCD type IIa. A trend was found between fast activity and PNH, rhythmic sharp activity and FCD type I, repetitive fast spikes bursts and FCD type IIb, slow burst and HS. In 62 of the 102 patients, a complete surgical resection of the SEEG-SOZ was performed, and in 12 patients a partial resection was carried out to preserve eloquent areas. In 18 patients (15 with PNH) the SEEG-SOZ was thermo-coagulated. Seizure freedom was achieved in 58% of surgically treated patients and in 72% of those treated with thermocoagulation (mean ± SD follow-up 5.9 ± 2.3 years). Seizure freedom after surgery was achieved in 84% of the patients with PMG, FCD I, IIa and IIb presenting with characteristic SEEG-SOZ patterns. With the exception of FCD type II, interictal activity was not sufficient to identify SEEG-SOZ boundaries. Conclusion : The study demonstrates that specific histopathologies correlate with particular neurophysiological patterns, reflecting lesion-specific seizure patterns in focal epilepsies.