Pinpointing the Seizure

New techniques lead to more precise diagnosis and better treatment.

Many epilepsy sufferers need advanced treatment to regain control of their lives.

• Epilepsy is a neurological condition in which brain function is disrupted by seizures.
• There are many types of epilepsy, and many types and severities of seizures.
• Seizures disrupt lives physically and emotionally, can lead to injuries, and can affect the entire family.
• 2.2 million estimated sufferers in the U.S. — roughly 2/3 the population of the Twin Cities.
• Medication controls seizures in 60% of sufferers; stimulation therapies, dietary treatment, and sometimes surgery can help those who are not controlled with medication.

Identifying where the seizure starts in the brain is critical.

If the seizure source is precisely located and contained in a non-critical part of the brain, that portion of the brain can be surgically removed.

Advanced methods enable pinpoint-accuracy in the detection of the seizure focus.

Observing blood flow

SPECT, SISCOM and STATISCOM techniques

• During a seizure, blood flow increases in the affected area of the brain.
• Low dose of radioactive material is injected, which highlights the area of the increased blood flow.
• Single photon emission computerized tomography (SPECT) images of the brain are taken during a seizure and at baseline.
• Baseline brain activity is subtracted from seizure to create SISCOM images, revealing the areas causing the seizure.

Tracking electrical activity

Stereo electroencephalogram (sEEG)

• Looks at electrical activity with multiple electrodes implanted in the brain.
• Allows precision targeting of specific regions located deep and on the surface.
• By identifying which electrodes are activated by the seizure, doctors can determine the seizure source.

Detecting changes in chemistry

Positron emission tomography (PET) MRI

• Radioactive glucose is injected.
• The part of the brain giving rise to seizures often shows decreased glucose uptake.
• The area of seizure onset appears as a "cold spot" on the PET image.
• The "cold spot" is superimposed on an MRI obtained at the same time, showing the anatomic area of the seizure focus.

Detecting subtle lesions in the brain

Morphometric analysis program (MAP) imaging

• Magnetic resonance imaging (MRI) of the brain is taken.
• MAP highlights thickened areas of the cortical surface.
• Focal cortical dysplasia, a potential surgically treatable lesional cause of epilepsy, can be identified by MAP imaging.

Sources: MayoClinic.org; Epilepsy.com.