Focal epilepsies: Update on diagnosis and classification

Abstract

Correctly diagnosing and classifying seizures and epilepsies is paramount to ensure the delivery of optimal care to patients with epilepsy. Focal seizures, defined as those that originate within networks limited to one hemisphere, are primarily subdivided into focal aware, focal impaired awareness, and focal to bilateral tonic-clonic seizures. Focal epilepsies account for most epilepsy cases both in children and adults. In children, focal epilepsies are typically subdivided in three groups: self-limited focal epilepsy syndromes (e.g., self-limited epilepsy with centrotemporal spikes), focal epilepsy of unknown cause but which do not meet criteria for a self-limited focal epilepsy syndrome, and focal epilepsy of known cause (e.g., structural lesions-developmental or acquired). In adults, focal epilepsies are often acquired and may be caused by a structural lesion such as stroke, infection and traumatic brain injury, or brain tumors, vascular malformations, metabolic disorders, autoimmune, and/or genetic causes. In addition to seizure semiology, neuroimaging, neurophysiology, and neuropathology constitute the cornerstones of a diagnostic evaluation. Patients with focal epilepsy who become drug-resistant should promptly undergo assessment in an epilepsy center. After excluding pseudo-resistance, these patients should be considered for presurgical evaluation as a means to identify the location and extent of the epileptogenic zone and assess their candidacy for a surgical procedure. The goal of this seminar in epileptology is to summarize clinically relevant information concerning focal epilepsies. This contributes to the ILAE's mission to ensure that worldwide healthcare professionals, patients, and caregivers continue to have access to highquality educational resources concerning epilepsy.

Causal link between oxidative stress and epilepsy: A two‐sample Mendelian randomization study

“…This study investigated the causal associations between 7 epilepsy Our finding of a causal association between the focal NHS and urate is partly consistent with two cross-sectional population-based studies, which compared untreated epilepsy patients to healthy controls (Aycicek & Iscan, 2007;Hamed et al, 2004). Epileptic foci other than HS may result from a variety of causes such as stroke, trauma, tumors, and developmental malformations (Nascimento et al, 2023). The level of serum urate levels has been reported to be elevated in epilepsy secondary to cerebral infarction and trauma (Jackson et al, 2016;Wang et al, 2019).…”