How Is Epilepsy Diagnosed?
Learn how neurologists diagnose common seizure disorder
Learn how neurologists diagnose common seizure disorder
Epilepsy is a type of brain disorder characterized by recurring seizures. Caused by abnormal electrical activity in the brain, epilepsy is a chronic condition that can affect anyone regardless of age, race or gender. An estimated 3.4 million people in the United States are living with epilepsy.
“An epilepsy diagnosis can be challenging because it is not a single disease but rather a spectrum of disorders,” says Nicholas Jonas, MD, a neurologist who specializes in clinical neurophysiology and epilepsy at Scripps Clinic Torrey Pines and Scripps Clinic Anderson Medical Pavilion in La Jolla.
“Head trauma, infections of the central nervous system and developmental disorders may be to blame in some cases, but in many cases of epilepsy, we may not find a direct cause,” Dr. Jonas says.
Symptoms of epilepsy
Not all seizures are directly related to epilepsy. To diagnose epilepsy, physicians look for signs of recurrent unprovoked seizures events. Typically, these occur without warning and can affect a person’s movement, perception and behavior.
The type, frequency and severity of epileptic seizures vary; some people may have brief lapses in awareness or seem to “freeze” for a few moments, while others may have full-body convulsions.
Physicians categorize seizures based on where they start in a person’s brain, their level of awareness during a seizure and whether muscle movements are involved.
Types of seizures
There are two major seizure categories:
Focal onset seizures
These start in a single cluster of neurons on one side of the brain. In these cases, physicians will use terms to try and describe what occurs during the seizure.
Focal onset aware seizure means the person is awake and aware during the seizure and may experience changes in their senses or emotions.
Focal motor seizures describe uncontrolled muscle movement in the face, arms or legs.
Focal onset impaired awareness seizure means the person is confused or unaware of what is happening during the seizure; symptoms may include memory loss, blank stares or repetitive movements with the eyes, mouth or hands.
Generalized onset seizures
These affect a broad network of neurons on both sides of the brain. Depending on the type of generalized onset seizure, symptoms may include a blank stare, muscles weakness or muscle rigidity, jerking muscles, severe convulsions and loss of consciousness and bodily functions.
How Is epilepsy diagnosed?
Diagnosing epilepsy usually requires several steps. Remember, not all seizures are directly related to epilepsy. Various conditions can cause seizures, such as stroke, meningitis, high fever and illegal drugs. The diagnostic process first aims to determine whether symptoms truly result from epilepsy or another cause.
“We take a comprehensive history of the patient’s seizures, including their duration, frequency and what seems to trigger them,” says Dr. Jonas. “If people have witnessed a seizure, their descriptions of what happened often provide valuable insights.”
Doctors will also perform a physical exam to evaluate the patient’s neurological function, such as their reflexes, motor skills and sensory responses. This helps rule out other neurological disorders.
Additionally, blood tests can help detect infections, metabolic disorders or genetic conditions that may contribute to seizures. Brain imaging techniques, such as magnetic resonance imaging (MRI) or computed tomography (CT) scans, may help identify structural abnormalities, tumors or injuries that might be causing seizures.
Electroencephalogram (EEG) is a critical tool in diagnosing epilepsy. An EEG records the brain’s electrical activity and can detect abnormal patterns associated with seizures. In some cases, the test may be conducted during sleep or while exposing the patient to potential seizure triggers to capture unusual brain activity.
“In some cases when the diagnosis is unclear or seizures are not controlled by medication, we may recommend long-term monitoring in our inpatient epilepsy unit at Scripps Memorial Hospital La Jolla,” says Dr. Jonas. “This allows us to directly observe seizure activity in real time.”
Over a two-to-four-day period, Scripps neurologists who are epilepsy specialists use continuous EEG monitoring combined with video surveillance to record the exact moment someone has a seizure. Inpatient epilepsy monitoring can pinpoint where the problem occurs in the brain, helping physicians confirm an epilepsy diagnosis and determine the most appropriate treatment.
Epilepsy treatment options
While there is not yet a cure for epilepsy, several treatments can effectively control or reduce the frequency of seizures. Treatment depends on the type of epilepsy, the patient’s overall health and their response to various therapies.
Daily medication is the most common treatment to prevent seizures. Finding the right medication often involves trial and error as not every drug works for every patient.
If patients know what triggers their seizures, such as lack of sleep, alcohol or flashing lights, they can try making lifestyle modifications to avoid or minimize those triggers.
Surgery may be an option for patients whose seizures originate from a specific, identifiable area of the brain that can be safely removed. Another surgical treatment, implantation of a vagus nerve stimulator (VNS), helps block seizure-producing electrical activity in the brain to reduce the frequency and intensity of seizures in some patients.
“Early and accurate diagnosis of epilepsy can significantly improve outcomes,” says Dr. Jonas. “With the appropriate care and support, many individuals with epilepsy can better control their seizures control and enjoy a higher quality of life.”