Brain SPECT is a way for your physician to see how blood is flowing through different areas of your brain. This page was written to help you further understand brain SPECT and to answer questions most frequently asked by people scheduled for SPECT brain imaging studies.

What is a SPECT brain scan?

A SPECT (single-photon emission computed tomography) brain scan is a diagnostic nuclear medicine imaging procedure that permits physicians to visualize brain function by obtaining three-dimensional images of the brain.

Why does my doctor want me to have a SPECT brain scan?

A SPECT brain scan can show how well the various regions of your brain are functioning. This information can help your doctor make a more accurate diagnosis.

Even if I have already had x-rays, a computed tomography (CT) scan and/or a magnetic resonance imaging (MRI) scan, why do I still need another test?

To fully evaluate a patient's symptoms, information on both the brain's structure (anatomy) and its blood supply is often necessary. CT and MRI provide detailed information on the structure of the brain. However, in many patients the symptoms cannot be completely explained by anatomic changes, or these scans may appear normal. Brain SPECT can often give your physician important information on blood flow that would not be available through these other diagnostic techniques. The best diagnosis for some patients is made only after evaluating the blood flow to various areas of the brain and comparing these to normal patterns. The changes that may be detected on brain SPECT studies are diagnostic of some diseases. When doctors combine information on your brain's anatomy and function, they have a more complete understanding of what may be causing your symptoms. Brain SPECT can also be used to evaluate the success of various treatments.

Can I eat or drink before the exam?

Yes! Brain SPECT doesn't require fasting, special diets, or medication. If you're not in the hospital, you can continue your regular work schedule and lifestyle. Many people drive to the hospital or clinic, park, and walk in for the brain SPECT scan.

What can I expect?

On the day of the exam you will check in at the Nuclear Medicine Department. First, a doctor or nuclear medicine technologist will ask you some important questions, such as: Are you pregnant? Is there any chance that you may be pregnant? Do you have a history of head injury, seizures, or stroke? Next, the technologist will have you lie on your back in a quiet, darkened room, which may or may not be the examination room. An intravenous catheter or needle will be placed in a vein in your arm or hand, and a radiopharmaceutical will be injected soon afterward. You will then be asked to continue lying quietly for another 10 to 20 minutes. When it is time for the examination, you will lie down on the padded examination table. The SPECT camera, capable of imaging the areas of your brain where the radiopharmaceutical has accumulated, will be moved near your head. The closer the camera is to your head, the better the images of the blood flowing in your brain will be.

Will I feel anything when the drug is injected?

You will feel only a small prick from the needle when it is placed in the vein. The injection itself is painless if the needle is properly placed. Adverse reactions to the radiopharmaceutical are very rare, and when they do occur, usually involve only a mild, self-limited skin reaction such as a rash.

Is the radiopharmaceutical a dye?

No, it is a radioactive agent that will localize in an area of the brain and will be imaged with a camera.

How long will the exam take?

You will be imaged shortly after injection of the radiopharmaceutical. Preparation may take about a half-hour, and the SPECT imaging procedure takes about a half-hour.

Procedure for a SPECT Brain Scan

The SPECT camera will take a series of pictures of your head that will show how well blood flows through the various areas of your brain. The only noise you will hear will be the mechanical rotation of the camera, which is only a slight noise. There are no loud noises associated with the examination.

Will the SPECT camera touch me?

The camera will rotate once around your head and may lightly brush against the tops of your shoulders. Otherwise, no part of the machinery will touch your body.

Will I be enclosed in a small confined space?

No. However, the camera will be close to your head throughout the exam.

What should I do during the examination?

Simply relax, and follow the technologist's instructions. Your only participation will be to remain as still as possible during the exam and breathe normally. It is very important for you to be comfortable before the scan begins. Movement of the head while the pictures are being taken may require that the scan be repeated. The technologist will keep you informed about what is going on. Once the picture taking is over, you can relax, read, have a cup of coffee. The technologist will process the pictures taken by the SPECT camera.

Will I feel anything during the exam?

Not a thing; the SPECT brain scan is painless.

Who will be with me?

A technologist will be in the examination area, where he/she can constantly see and hear you.

Following the Procedure

If you are an inpatient, you will be returned to your hospital room. If you are an outpatient, you may go home and continue your regular activities.

How much radiation exposure will I receive as a result of this exam?

The total body radiation exposure from a SPECT brain scan is small - in the range of 1 to 3 times your annual exposure to natural background radiation.

When will I get the results of my exam?

A report describing the findings of your SPECT brain scan will be sent to your physician, who will then contact you.

Who can answer any other questions I might have?

Your personal physician, or a physician, nurse, or technologist in the nuclear medicine department.

Please note that this information is provided for educational purposes only. It is not intended to substitute for informed medical advice. The user of this site should not use this information to diagnose or treat a health problem or disease without consulting with a qualified health care provider.

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