Patients with focal epilepsy have focal seizure types, and may have typical interictal and/or ictal EEG findings that accompany focal seizure types (such as focal sharp waves or focal interictal slowing). Imaging showing a focal structural brain abnormality may be supportive, although patients with genetic etiologies and normal imaging can also have focal epilepsy. Focal epilepsies may be unifocal, multifocal or hemispheric.