Contrast Cisternogram

A contrast cisternogram combines x-rays and computed tomography (CT) to evaluate the circulation of cerebrospinal fluid. This procedure helps identify certain types of tumors and cysts and provides information about other abnormalities in the brain.

How to Prepare

When you schedule your cisternogram, you will be told whether the procedure will be performed on an inpatient or outpatient basis. If it is to be performed on an outpatient basis, please arrive at the time and location given you. You can expect to go home the same day, approximately six hours after the cisternogram is completed.

If you will be admitted to the hospital for this procedure, please arrive at the time and location given to you. You will probably be discharged from the hospital the next day.

Prior to undergoing this procedure, your CINN Outpatient Center nurse may arrange for you to have a blood test.

Do not eat or drink anything after midnight the day before and morning of your cisternogram. If you are on any medications, you may take them with sips of water. If you are a diabetic, discuss your medication with your CINN physician.

Bring a loose-fitting outfit with you to the hospital. Wearing comfortable clothes while returning home will minimize any discomfort you experience.

You must arrange for a friend or family member to drive you home, unless you are staying at the hospital overnight.

Do not take any aspirin or aspirin-containing products including Alka Seltzer, Anacin, Bufferin, and Empirin for one week prior to your appointment. Also, do not take Darvon, Naprosyn, Voltaren, Indocin or any products containing ibuprofen including Advil and Motrin for one week prior to your appointment. Ask your CINN physician when you can resume taking these medications. You may take Tylenol and acetaminophen.

Tell your CINN physician if you are pregnant or if you have any allergies, such as those to any medications, shellfish, or iodine or other contrast solutions.

If you regularly take a blood-thinning medication, such as aspirin or Coumadin, notify your CINN physician. Your dosage may be adjusted in preparation for the contrast cisternogram.

If you develop a cold, fever, or flu symptoms before your scheduled appointment, contact your CINN physician.

What to Expect

Once you are settled in your room, you will be asked to disrobe and put on a hospital gown. Do not bring any jewelry or other valuables to the hospital the day of your test.

Next you will be taken to the CT scanning room for a two-part CT scan of your head. A technologist will help you onto a narrow table, which is padded but may be slightly uncomfortable. For the first part of the scan, you will lie on your stomach with your chin extended forward.

Any movement during a CT scan will make the images blurry. Therefore, the technologist might place bands around your head and body to help you keep still. When all preparations have been made, the examination table will move automatically into a large, doughnut-shaped ring while you relax and remain still. Only your head will be inside the device.

While the procedure is underway, the scanner will rotate around you. A great number of x-ray beams, each of a low dosage and lasting only a fraction of a second, will pass through your body at different angles. You will hear the sound of gears moving and a motor running during this procedure.

After the scans are complete, the table will move out of the ring and the technologist will reposition you for the second part of the CT. You will lie on your back with your arms at your sides and your head in a headrest. Then the table will slide back into the ring again. Only your head will be inside the device. Again, the scanner will rotate around you and x-ray beams will pass through your body at different angles.

When the CT scans are complete, you will be taken to the x-ray room. There, you will lie on your abdomen or side on an examination table. A radiology nurse may give you a mild sedative to help you relax.

Then the radiologist will begin the process of removing a small amount of your cerebrospinal fluid for laboratory analysis. He or she will use an antibacterial solution to cleanse the selected insertion site on your back or neck, then inject a local anesthetic to numb the area. You may feel a burning sensation for a few seconds when the anesthetic is injected. After the area is numb, the radiologist will insert another needle through your skin and into the fluid-filled space that surrounds your spinal cord. You will not feel any sharp pain, although you may feel as though someone is putting pressure on your back. The radiologist will then use the needle to withdraw the cerebrospinal fluid.

Next a contrast solution (a water-soluble dye) will be injected through the needle into the fluid-filled space. This may cause you to feel some pressure in the area that is injected. The contrast solution will allow the radiologist to see the flow of your cerebrospinal fluid more clearly and identify any abnormalities more easily. After the contrast solution is injected, the radiologist will take a series of x-rays. Then the radiologist will remove the needle from your spine.

After the test, a hospital transporter will take you back to the CT scanning room to undergo a second series of CT scans. As was done previously, the scans will be taken in two parts, first with you on your stomach and then with you on your back. After the second CT is completed, a hospital transporter will take you back to your room, where you will remain in bed with your head elevated for the next six hours. When you need to empty your bladder, your nurse will assist you with a urinal or bedpan.

If you are undergoing the test as an outpatient, a family member or friend must drive you home. After you return home, please continue on bed rest for 24 hours. While on bed rest, you may use the bathroom and sit up to a 30 degree angle for meals.

If you remain in the hospital overnight, you may drive yourself home after you are discharged. Although you do not have to go on bed rest after returning home, please take it easy for the next day or so.

You may experience side effects caused by the removal of some of your cerebrospinal fluid. The most common side effect is a headache that persists for several hours or up to several days. Symptoms that may accompany a headache include nausea, vomiting, dizziness, or tightness in the shoulders, base of the neck, or lower back.

Unless otherwise instructed drink plenty of fluids for the remainder of the day of your exam. This will help flush the contrast solution from your system and may help you avoid a headache. Drinking caffeinated beverages may be especially helpful in relieving a headache, as may lying down. You may take Tylenol; do not, however, take any aspirin-containing medications.

You will probably be able to resume your normal activities after 24 to 48 hours. If, after this time, you are still experiencing a headache or any other symptoms, please call your CINN physician.