Pathology-based approach to epilepsy surgery

Abstract

surgical candidacy has broadened as a consequence. However, even twenty-first century technology still falls vexingly short of solving the problem for many patients. the role of specialists is to seek solutions, and explore paradigm shifts that often proves useful to advance knowledge and decision-making. Historically, the epilepsy surgery ‘jargon’ has been one of dividing the brain into anatomical compartments and exploring the corresponding types of epilepsies based on the localization of the epilepsy onset (e.g., temporal, frontal, parieto-occipital lobe epilepsies). terms such as temporal lobe or frontal lobe epilepsies became entrenched in the literature and in the mind of those evaluating and operating on patients. Outcomes, however, have been widely diverse and, to some extent, continue to be suboptimal. Focal epilepsy as a clinical phenotype could be considered as the final common pathway of various and diverse etiologies that include focal lesions (tumors, scars, vascular malformations, or cortical dysplasia), multilobar lesions (cortical dysplasia, tuberous sclerosis, destructive lesions), hemispheric (hemimegalencephaly, rasmussen’s encephalitis) or bihemispheric (cortical dysplasia, tuberous sclerosis). An increased knowledge of the natural history of epilepsies due to different lesions, of the clinical/ electrophysiological/imaging presentations and treatment outcomes of these epilepsies suggest distinct characteristics that go beyond the anatomical location of epilepsy phenotype. In this topic-related cluster of review articles, we claim that development of epilepsy (epileptogenesis) and expression of epilepsy (epileptogenicity) largely depend on causative abnormality(ies) in patients suffering from pharmaco-resistant focal epilepsies: previous studies addressing presurgical evaluation and postsurgical outcome highlighted important roles for the interactions between the Despite the introduction of scores of antiepileptic medications over the last two decades, a sizable number of patients (almost one-third) with epilepsy continue to have seizures. In fact, the growing realization that pharmaco-resistant epilepsy carries both a significant mortality risk and lingering psycho-social stigmata highlights the challenge to provide effective medical treatment for a significant percentage of patients. In this group of patients with pharmaco-resistant focal epilepsy, resective surgery has become the treatment of choice. long-term follow-up studies on the success and complications of epilepsy surgery have been published by various centers of excellence. these studies showed the efficacy of resective surgery in seizure control and established new outcome “benchmarks”. these positive developments and the expertise gained by the epilepsy community in managing difficult to medically treat epilepsy patients, led to a significant increase in the number of epilepsy programs around the world and heightened awareness of referring physicians and patients about the benefit of epilepsy surgery. Furthermore, there have been advances in neurophysiological and neuroimaging evaluation protocols, and