Interictal and Ictal MEG in presurgical evaluation for epilepsy surgery

Although presurgical evaluation of patients with pharamacoresistent focal epilepsies provides essential information for successful epilepsy surgery,there is still a need for further improvement.Developments of noninvasive electrophysiological recording and analysis techniques offer additional information based on interictal and ictal epileptic activities.In this review,we provide an overview on the application of ictal magnetoencephalography(MEG).The results of a literature research for published interictal/ictal MEG findings and experiences with own cases are demonstrated and discussed.Ictal MEG may provide added value in comparison to interictal recordings.The results may be more focal and closer to the invasively determined seizure onset zone.In some patients without clear interictal findings,ictal MEG could provide correct localization.Novel recording and analysis techniques facilitate ictal recordings.However,extended recording durations,movement and artifacts still represent practical limitations.Ictal MEG may provide added value regarding the localization of the seizure onset zone but depends on the selection of patients and the application of optimal analysis techniques.

Preoperative evaluation and surgical strategy for epileptic spasms in children

Epileptic spasm(ES)is one of the most common types of seizures in children.It is primarily characterized by brief axial contractions lasting less than 2 s and recurring in short clusters.It usually occurs in children of 3 to 12 months of age,although it can also occur after the age of 1 year.In general,children with ES develop other symptoms of epilepsy,such as tonic,tonic-clonic,or focal seizures,after 3 to 5 years of age.ES in children is often damaging and usually results in developmental regression.First-line treatments for spasm seizures include adrenocorticotropic hormone(ACTH)and vigabatrin.However,many patients fail to respond to these medications,and continued to have spasms associated with progressive neurodevelopmental degeneration.Therefore,it is important to consider whether children with drug resistance meet surgical indications to consider surgical treatment in such conditions.In this study,we reviewed and summarized the importance of preoperative evaluation in order to provide surgical options for treatment of children with ES.

The cultivation of epilepsy neurosurgeons:requirements and challenges

Epilepsy surgery has been accepted as an effective treatment in drug-resistant focal epilepsy.However,the number of epilepsy neurosurgeons is not enough in China compared with the huge demand.The content of epilepsy neurosurgeon cultivation includes surgery itself as well as presurgical evaluation.In this article,we review not only different categories of epilepsy surgeries but also the presurgical evaluation approaches including non-invasive methods,such as semiology analysis,high-resolution structural and functional imaging techniques,scalp electroencephalography monitoring as well as invasive methods,such as electrocorticography (ECoG) and stereotactic electroencephalography (SEEG).We also discuss the importance of learning each method briefly.In addition,we suggest that epilepsy neurosurgeons should have a solid structural and functional anatomy basis as it plays pivotal role in localizing epileptogenic zone.Epilepsy neurosurgeons should also be familiar with the staged presurgical evaluation starting from the most preliminary examinations and progressing to more complex and invasive methods.During the diagnosis and therapeutic procedures,collaboration between epilepsy neurosurgeons and other specialists is essential.At last,the necessity of epilepsy neurosurgeon cultivation has been emphasized.