Why do I need a Brain SPECT Scan?
The SPECT scan helps identify your seizure focus, or the place in your brain where your seizures start.
What is a Brain SPECT Scan?
The SPECT Scan produces pictures that show the areas where blood flows through your brain.
How does brain blood flow show where my seizures start?
During a seizure, more blood flows through the most active parts of the brain (the seizure focus). We do two SPECT scans. One is done during a seizure (ictal study). Another is done as far away in time from a seizure as possible (the interictal study). Then we compare the two scans to look for an area where the blood flow changed.
Where are SPECT scan procedures done?
The equipment for doing a SPECT scan is in the Nuclear Medicine Department at Strong Memorial Hospital, which is only open from 8AM to 3PM.
First we do the interictal study (non-seizure) on a Monday morning. After this is completed you will be admitted to the Strong Epilepsy Center (SEC) at Strong Memorial Hospital for your ictal study, which is done during a seizure. Electrodes will be placed and other equipment for Long Term Video Monitoring will be hooked up.
What happens during the procedure?
In most cases, on Monday afternoon or evening, your antiseizure medications will be reduced to make seizures more likely to occur. On Tuesday morning, you will be taken to the Nuclear Medicine Department at approximately 8AM where you will stay until you have a seizure. If you do not have a seizure that day, you will return to the inpatient unit for the evening, the following day you will return to Nuclear Medicine. This process is repeated until you have a seizure. A family member or someone who knows your seizure type is required to stay with you. They will alert the nuclear medicine technicians when you are having a seizure.
When the seizure occurs, a technician will inject a radiopharmaceutical through an IV in your arm. Then, the EEG electrodes will be removed and within a few hours the scan will be performed.
During the scan, you will be lying on your back on a special table. It is important that you remain very still. A gamma camera will take pictures over the next 30 minutes. If you move too much, the pictures may need to be repeated.
How will I feel during this procedure?
You will not feel any effect from the material that is injected. The injection will be done through an IV that was placed earlier. Other than the slight discomfort from placing the IV, there is no pain associated with this procedure. The hardest part is waiting for the seizure and then lying still during the scan.
What is the substance that is injected?
It is a radiopharmaceutical called technetium-99m (Neurolite or Spectamine). A very small volume is injected, typically less than a fifth of a teaspoon. The radiation exposure from this radiopharmaceutical is low and within the range of common x-ray procedures. There have been no reported adverse effects due to the use of this substance.
What happens after 3PM when I return to my room?
If a seizure has not yet occurred, the SEC physician will usually further decrease the dose of your antiseizure medications. This dose varies from patient to patient. You will return to the Nuclear Medicine Department the following day.
Once the ictal SPECT scan (the study during a seizure) has been completed, your usual antiseizure medications will be restarted. You will be able to go home that day or the next day. There are no residual effects from the SPECT scanning.
How will I know find out about the results of the SPECT scan test?
Physicians at the Strong Epilepsy Center (SEC) will analyze the images taken of your brain. At the follow-up clinic visit, your SEC doctor will explain what we have learned about your seizures.