Focal seizures are caused by abnormal electrical activity that is limited to a specific area in one region of the brain. In some cases, the abnormal electrical activity can spread from one region to both sides of your brain. Focal seizures can cause a variety of symptoms, including loss of awareness and abnormal movements. However, they may also occur while you are fully aware without any movement-related symptoms.
UPMC epilepsy experts provide advanced care for focal seizures, including first-line treatment with antiseizure medications. If seizures continue with medications, our neurologists will work with our neurosurgery experts to discuss surgical options to reduce seizure activity.
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What Are Focal Seizures?
Focal seizures are caused by abnormal electrical activity that is limited to a specific area in one region of the brain. In some cases, the abnormal electrical activity can spread from one region to both sides of your brain. Focal seizures can cause a variety of symptoms, including loss of awareness and abnormal movements. However, they may also occur while you are fully aware without any movement-related symptoms.
What are the types of focal seizures?
There are three types of focal seizures:
- Focal-aware seizures (FAS) — These can produce sensory or motor symptoms while you remain fully aware.
- Focal-impaired awareness seizures (FIAS) — These can produce a variety of symptoms but involve loss of awareness for the full duration or at least part of the seizure.
- Focal to bilateral tonic-clonic seizures (FBTCS) — These seizures start in one particular region of the brain and spread to involve both sides of the brain, often producing convulsive or whole-body shaking events with loss of consciousness.
How common are focal seizures?
Focal seizures are the most common type of seizure in people over age 1, which makes up more than half of all seizures. Of people who have epilepsy, focal seizures affect more than half of these patients.
What causes focal seizures?
All epileptic seizures are caused by abnormal electrical activity in the brain.
Causes of abnormal electrical activity may include:
- Autoimmune disorders.
- Brain infections, such as encephalitis or meningitis.
- Brain injury, such as a traumatic brain injury.
- Brain tumors.
- Cerebrovascular problems, such as a ruptured aneurysm or stroke.
- Degenerative brain conditions, such as dementia.
- Drug or alcohol misuse or withdrawal.
- Eclampsia, which causes high blood pressure during pregnancy.
- Electrolyte imbalances.
- Genetic disorders.
- Heart problems, such as abnormal heart rhythms.
- High fevers.
- Hormone changes, particularly in women.
- Lack of oxygen in the brain.
- Metabolic problems, such as high or low blood sugar levels.
- Sepsis.
Focal seizure risk factors
Seizures can occur at any age.
You may be at higher risk for focal seizures if you:
- Experience a head injury with loss of consciousness.
- Have a family history of epilepsy.
- Have an untreated infection that could spread to your brain, such as in your ears, eyes, or sinuses.
- Have uncontrolled chronic health conditions, such as diabetes, high blood pressure, or obstructive sleep apnea.
- Misuse alcohol, prescription medications, or drugs.
Complications of focal seizures
Seizures can cause physical injury and death.
Serious complications of focal seizures may include:
- Status epilepticus — Long-lasting seizures or seizures that occur one after another.
- Sudden unexplained death in epilepsy (SUDEP) — A rare condition that causes sudden death without a clear cause in people with epilepsy, often during sleep.
How can I prevent focal seizures?
Seizures can affect anyone, so you may not be able to prevent them.
However, you may be able to reduce your risk by:
- Avoiding misuse of alcohol, prescription medications, or drugs.
- Avoiding known or possible seizure triggers.
- Getting timely treatment for infections.
- Managing chronic health conditions.
- Taking antiseizure medications as prescribed.
- Wearing head protection when recommended to reduce the risk of brain injury.
What Are the Signs and Symptoms of Focal Seizures?
Focal seizure symptoms can affect motor, sensory, autonomic, and cognitive function.
Symptoms may include:
Motor symptoms
Motor symptoms often involve involuntary movements on one side of the body and may include:
- Repetitive movements, such as blinking or tapping.
- Temporary paralysis after the seizure is over.
- Tightening of muscles.
- Twitching or jerking movements.
Sensory symptoms
Sensory symptoms can cause problems with your senses, including:
- Hearing distortions, including hearing abnormal sounds.
- Smell distortions, including smelling something that isn’t there.
- Taste distortions, including an unexpected sour, metallic, or bitter taste in your mouth.
- Touch distortions, including pins and needles, temperature changes, or a crawling sensation on your skin.
- Vision distortions, including seeing bright lights, flashes, or other visual changes.
Autonomic symptoms
Autonomic symptoms affect your body’s critical automatic functions, and may include:
- Changes in heart rate or palpitations.
- Changes to skin color.
- Feeling hot or excessive sweating.
- Nausea or vomiting.
Cognitive symptoms
Cognitive symptoms affect your emotions and thinking and may include:
- Agitation.
- Anger.
- Anxiety.
- Excitement.
- Fear.
- Flashbacks.
- Inability to speak.
- Joy.
- Loss of memory.
- Uncontrollable laughter.
When should I see a doctor about my focal seizure symptoms?
If you have symptoms of focal seizures, you should schedule an appointment with your provider right away. If your seizure symptoms are severe, dial 911 or ask someone to take you to the nearest hospital Emergency Department.
How Do You Diagnose Focal Seizures?
To diagnose focal seizures, your provider will perform a physical examination and review your symptoms and medical history. Your provider may also order tests to confirm your diagnosis or rule out other problems.
What to expect during your visit
During your visit, your provider will:
- Ask you about your symptoms.
- Order tests.
- Perform a physical and neurological exam.
- Review your medical history.
Tests to diagnose focal seizures
Your provider may order tests to confirm your diagnosis or rule out other conditions, including:
- Blood tests — Checks for infections and abnormalities.
- Cerebral spinal fluid analysis (spinal tap or lumbar puncture) — Involves inserting a needle into your lower back to collect a sample of cerebrospinal fluid (CSF) for analysis in a lab.
- Electroencephalogram (EEG) — Checks for abnormal electrical activity in your brain that may cause seizures.
- Magnetic resonance imaging (MRI) — Creates images of your brain to look for damaged or abnormal areas.
- Video-EEG monitoring — Uses EEG in combination with video monitoring to capture physical symptoms during seizures or episodes of concern.
- Neurological examination — A noninvasive physical exam to check your reflexes, balance, movement, memory, and ability to think.
Focal seizure prognosis
Your prognosis after a focal seizure diagnosis depends on the cause and severity of your condition. In many cases, focal seizures can be controlled with antiseizure medications. However, if medications aren’t effective, surgical options to treat your seizures may be pursued.
How Do You Treat Focal Seizures?
The goals of focal seizure treatment are to prevent seizures, minimize treatment-related side effects, and improve quality of life.
Treatment options may include:
Lifestyle changes
If you and your epilepsy care team can identify triggers that lead to focal seizures, you may be able to make lifestyle changes to reduce the number of seizures you experience. Identifying and treating the underlying cause of your seizures, such as a brain tumor or brain infection, may prevent further seizures. However, a cause for seizures is determined in only approximately 40% of patients.
Dietary changes
Your provider may recommend following a specialized, high-fat, low-carbohydrate diet, such as the ketogenic diet, to help manage seizures.
Medications for epilepsy
Medications are first-line treatment for focal seizures and help to control them in most people with epilepsy. Your provider will work with you to identify the medications, or combination of medications, that work best for you with minimal side effects.
Surgery to treat epilepsy
In at least one-third of people with epilepsy, focal seizures continue even with medication.
Epilepsy surgery may be an effective option if:
- Medication side effects are not tolerable.
- At least two different medications have not been effective at controlling seizures.
UPMC neurosurgeons offer a range of surgical options for people with epilepsy, including:
Diagnostic surgery
Also known as intracranial monitoring or stereo-EEG, this procedure helps neurosurgeons pinpoint the origin of seizures within the brain. UPMC neurosurgeons use the ROSA® (robotic stereotactic assistance) Robotic System to perform minimally invasive procedures more accurately for epilepsy and movement disorders.
Neurosurgical procedures
Neurosurgical procedures for epilepsy include:
- Craniotomy for resection of seizure focus — Involves surgically removing the abnormal brain tissue causing seizures.
- Laser ablation — Minimally invasive surgery using focused heat to destroy the abnormal brain tissue causing seizures.
Other less commonly performed surgeries include multiple subpial transections (MST), corpus callosotomy, and other procedures that reduce abnormal electrical impulses in the brain.
Neuromodulation device implantation
Your neurosurgeon may recommend a procedure to implant a neuromodulation device that sends electrical impulses to your brain. These impulses regulate or disrupt abnormal electrical signals and can help to reduce seizures.
Procedures include:
- Deep brain stimulation (DBS) — Implantation of electrodes in the brain to directly deliver electrical impulses that can reduce seizure activity.
- Vagus nerve stimulation (VNS) — Implantation of a device in the chest that delivers electrical impulses to the vagus nerve in your neck to prevent or disrupt seizures.
- Responsive neurostimulation (RNS®) — Implantation of a device in the skull and electrodes in the brain that can detect seizure activity and respond with electrical stimulation to disrupt seizures.
Why Choose UPMC for Focal Seizure Care?
When you choose UPMC for focal seizure care, you will receive:
- Multidisciplinary care — Our team of neurologists, epileptologists, and neurosurgeons can work together to develop a customized epilepsy treatment plan that helps you manage seizures and minimize treatment side effects for medication-resistant epilepsy.
- Access to advanced clinical trials — Our team participates in national, multicenter clinical trials evaluating new epilepsy treatments, allowing you to contribute to research that advances seizure disorder care.
- Expert neurosurgery care — People with medication-resistant epilepsy can access cutting-edge, minimally invasive neurosurgery treatment options that may help reduce seizures and restore quality of life.
