Screening spreading depolarizations during epilepsy surgery.

BACKGROUND: Spreading depolarization (SD) is a fundamental pathophysiological mechanism of both pannecrotic and selective neuronal lesions following deprivation of energy. SD with brain injury has been reported including in one patient during an intracranial operation. However, the incidence of SDs in operative resections is unknown. METHODS: We performed (a) retrospective analysis of intraoperative AC-recordings of 69 patients and (b) a prospective study using intraoperative near-DC recording. All patients had the diagnosis of pharmaco-resistant epilepsy. Both studies were designed to determine the incidence and characteristics of SDs intraoperatively. In the retrospective analysis, we used intraoperative electrocorticography (iECoG) recordings obtained from AC-recording of 69 patients. In the prospective analysis, we used an Octal Bio Amp and Power Lab ECoG recorder with near-DC range. RESULTS: In the retrospective study, we included 69 patients with a mean of 1 h 3 min of iECoG recordings. In the prospective study, we recruited 20 patients with near DC recordings. A total of 35 h 41 min of iECoG recordings with mean of 2 h 32 min/patient were analyzed. We did not find SD in either study. CONCLUSIONS: SDs were not detected during intraoperative recordings of epilepsy surgery using AC- or DC-amplifiers.

Neuromodulation techniques for status epilepticus: A review.

BACKGROUND: Electroconvulsive therapy (ECT), Vagal Nerve Stimulation (VNS), Transcranial Magnetic Stimulation (TMS) and Deep Brain Stimulation (DBS) are neuromodulation therapies that have been used to treat Status Epilepticus (SE). OBJECTIVE: Review the literature about the efficacy and safety of neuromodulation therapies in SE in humans. METHODS: We searched studies in PubMed, Scopus, Google Scholar and Science Direct (inception to June 2018). Four review authors independently selected the studies, extracted data and assessed the methodological quality of the studies using the recommendations of the Cochrane Handbook for Systematic Reviews of Interventions, PRISMA guidelines, Oxford and GRADE scales, and Murad et al., 2018 methodological quality and synthesis of case series and case reports. RESULTS: We analyzed 27 articles (45 patients) with 4 different neuromodulation therapies. In ECT we found 80% rate of disruption of SE and 5% of adverse events was reported. Using iVNS 15/16 (93.7%) patients resolved the SE. All patients who underwent TMS and DBS aborted SE, however, 50% of patients with DBS had severe adverse events. CONCLUSIONS: Case series and case reports suggest that neuromodulation therapies can abort SE in 80-100% of patients (Oxford scale and GRADE were level 4 and D) with a wide range of adverse effects, which claims for prospective studies on the relationship be-tween efficacy and safety.

Neurosurgical Therapy for Status Epilepticus in Oligoastrocytoma Patients.

BACKGROUND: Super-refractory status epilepticus (SRSE) is a life-threatening neurologic emergency defined as "status epilepticus (SE) that continues 24 hours or more after the onset of anesthesia, including those cases in which the SE recurs on the reduction or withdrawal of anesthesia," which occurs in 10% to 15% of patients with SE and rarely has been resolved surgically. CASE DESCRIPTIONS: A 20-year-old man with SRSE and a long history of left parieto-occipital oligoastrocytoma was admitted for convulsive SE that became SRSE and underwent lesionectomy guided by electrocorticography and neuronavigation for local tumor recurrence. Histopathologic diagnosis was oligoastrocytoma. SRSE was aborted and the patient recovered fully without any functional deficits. CONCLUSIONS: The lesionectomy guided by electrocorticography and neuronavigation should be considered as a treatment option for patients with SRSE.