It depends on the cause rather than on the seizure type. Focal seizures arising from a stable scar or an old injury often stay much the same for years. Those caused by something active, such as a growing lesion or an inflammatory process, can increase, which is why the cause is investigated.
It depends on the cause rather than on the seizure type. Focal seizures arising from a stable scar or an old injury often stay much the same for years. Those caused by something active, such as a growing lesion or an inflammatory process, can increase, which is why the cause is investigated.
A focal seizure starts in one part of one hemisphere, and what happens over time is largely a property of whatever is producing it. Static causes, which are the majority in adults, include scarring from an old head injury or stroke, a developmental malformation of the cortex, and the changes of hippocampal sclerosis. None of those advance in themselves, and seizures from them often remain stable for many years, particularly on treatment. Active causes are the exception that matters: a tumour, an autoimmune encephalitis, an infection or a vascular malformation.
Focal seizures are described by whether awareness is retained or impaired, and by whether the electrical activity stays focal or spreads. When it spreads to involve both hemispheres the result is a focal to bilateral tonic-clonic seizure, which is what most people picture as a convulsion. A person can have both types. A change in the pattern, such as previously focal seizures beginning to generalise, or awareness now being lost when it was previously retained, is worth reporting, because it usually reflects control rather than a new disease.
EEG looks for the electrical signature between seizures and helps classify the epilepsy, which guides medication choice. A normal routine EEG does not exclude epilepsy, since it samples a short period; ambulatory EEG records over a longer stretch and raises the chance of capturing something. Both are performed in the office. Imaging answers the different question of whether there is a structural cause, and MRI is arranged at an imaging centre with the report reviewed with you here.
Several changes justify an earlier appointment rather than waiting: seizures that are new in type, longer than before, occurring in clusters, or followed by prolonged confusion; any injury sustained during a seizure; a clear increase in frequency after a stable period; and any new neurological symptom between seizures such as persistent weakness, speech difficulty or progressive headache. A first seizure, or a seizure lasting more than five minutes, is an emergency and needs immediate care.
Clinical Neurology Specialists has been physician-owned since 1998, when Leo Germin, M.D., FAANEM founded it. Five board-certified neurologists and four advanced practice providers see patients at the Las Vegas and Henderson offices, each with its own AANEM-accredited electrodiagnostic laboratory.
Clinical Neurology Specialists is an adult outpatient neurology practice for patients 18 and older. The practice performs no surgery and operates no imaging suite, infusion suite or interventional pain programme, and provides no emergency or inpatient care.
Physician-reviewed. Reviewed by the physicians of Clinical Neurology Specialists — board-certified neurologists, AANEM-accredited electrodiagnostic laboratories, physician-owned since 1998. Reviewed 1 August 2026. This article is general education for adults 18 and older and is not a substitute for a consultation.
Sources and further reading: MedlinePlus: epilepsy; National Institute of Neurological Disorders and Stroke; MedlinePlus, National Library of Medicine.
Adults 18 and older, at the Las Vegas and Henderson offices. Call 702-804-1212 or request an appointment online.