Presurgical evaluation and surgical treatment of medically refractory epilepsy

Abstract

With this informative article, the author presents a comprehensive review of the presurgical evaluation and surgical treatment of medically refractory epilepsy. Dr. Siegel is an experienced neurologist specialized in the field of epileptology and one of the most competent persons to deal with this subject. At the beginning, the author introduces the heterogeneity in the causes and clinical syndromes of epilepsy. He emphasizes the large number of potential candidates for surgical treatment, despite the variety of new antiepileptic drugs. The increasing interest in surgical treatment of medically refractory epilepsy is clearly reflected in the abundant literature that has become available during the past decades, of which the author has selected the most pertinent contributions for this article. After describing the concept of abnormal brain areas involved in interictal and ictal activity and the current indications for epilepsy surgery, Dr. Siegel concentrates on the stages of presurgical workup and surgical treatment of medically refractory epilepsy. The noninvasive evaluation comprises scalp electroencephalogram, magnetoencephalography, structural imaging, functional MRI, MR spectroscopy, SPECT, PET, and neuropsychological evaluation. The invasive evaluation of epileptogenic zones includes EEG recording and the amobarbital test. Surgical treatment of medically refractory epilepsy encompasses the full spectrum of surgical techniques such as temporal lobectomy, selective amygdalohippocampectomy, extratemporal resections, callosotomy, hemispherectomy and multilobar resections, multiple subpial transection, vagal nerve stimulation, and gamma knife radiosurgery. A great amount of information is presented in concise and very readable fashion. With 283 references, the article covers all important diagnostic and therapeutic aspects of medically refractory epilepsy. In summary, this review is most useful not only for neurologists and neurosurgeons specializing in epileptology but may also serve as a good introduction for residents entering training in epilepsy diagnosis and treatment.