When your healthcare provider recommends a head CT scan, they may specify whether it requires contrast material based on your specific medical condition. But what does this mean, and why is contrast sometimes necessary?
In this article, we’ll explain:
- What a CT scan with contrast can reveal.
- How healthcare providers decide whether contrast is needed.
- How to prepare for your appointment.
- What to expect during and after the scan.
What a head CT scan with contrast can show
A head CT scan with contrast provides enhanced imaging, offering greater detail about the brain, skull, and blood vessels that would not be revealed in a scan without contrast. It can help identify:
- Brain abnormalities, such as tumors or abscesses.
- Blood vessel conditions, including aneurysms or blockages.
- Signs of stroke or brain inflammation (e.g., meningitis).
When your healthcare provider recommends a head CT scan with contrast, it means they are looking for more information to help with diagnosing your condition.
What can a head CT scan reveal about my brain, skull, and blood vessels?
It can reveal signs of stroke, tumors, or bleeding in the brain, as well as fractures or injuries. Head CT scans can also highlight blood vessel abnormalities, like aneurysms, and detect conditions like a sinus infection.
Your provider may order a scan with contrast if your symptoms suggest a possible tumor, abscess, or growth in the brain, or to help understand more about blood vessel health and conditions, such as aneurysms or blockages.
What is contrast material?
Contrast material is typically an iodine-based substance that is given either orally or in an IV before a scan with contrast to highlight tissues and details of your body.
How can contrast enhance my head CT results?
The contrast is absorbed by tissues in ways that distinguish between healthy tissues and abnormal or diseased tissues.
Is contrast safe?
Contrast material is considered safe for most people, but if you have sensitivity to iodine or kidney issues, you should discuss this with your healthcare provider before the scan.
How does my healthcare provider decide between contrast or no contrast for a head CT scan?
The decision depends on your symptoms and medical history:
- Without contrast: Ideal for detecting head trauma or brain bleeding, as it provides sufficient detail for emergency cases.
- With contrast: Necessary for evaluating tumors, blood vessel health, or specific conditions like multiple sclerosis or epilepsy.
Tip: If you have a history of kidney issues or iodine allergies, let your provider know before scheduling the scan.
Why your doctor ordered a head CT with contrast
If your provider ordered a head CT scan with contrast, it’s likely to:
- Gain a more detailed view of the brain and blood vessels.
- Identify or rule out conditions like tumors, strokes, or infections.
- Make more accurate treatment recommendations based on precise imaging.
How does contrast help my provider to make a more accurate diagnosis?
The contrast will support a more accurate diagnosis because it reveals abnormalities that may be found in the brain and surrounding structures.
The contrast agent improves the visibility of internal abnormalities by attaching itself to unusual growths such as abscesses or tumors, as well as to blood vessels that may have an aneurysm or blockage.
Contrast can give your provider a more subtle and detailed understanding of a medical condition that may otherwise be more difficult to diagnose. This information helps shape possible treatment and interventions to better address the source of your symptoms.
What conditions can a head CT scan with contrast help to diagnose?
A head CT scan with contrast can help diagnose tumors or other growths like abscesses, inflammation of tissues that surround the brain and spinal cord (meningitis), inflammation of the brain itself (encephalitis), or the presence of infection.
A head CT scan with contrast can also help diagnose multiple sclerosis and epilepsy. Vascular conditions such as aneurysm, stroke, or inflammation of blood vessels can also be seen on a head CT scan with contrast.
What can a head CT scan with contrast reveal that would be difficult to see without contrast?
Blood vessels that are made brighter by the contrast can reveal blockages or tears that may otherwise go unnoticed. Tumors or growths are also made more prominent in images that use contrast, with size, nature, and location made clear.
The use of a contrast agent helps emphasize distinctions between healthy and unhealthy conditions by providing distinct details of abnormalities in the head.
Preparing for your head CT scan with contrast
Taking time to prepare will not only ensure that you get the most accurate available results but will also help the imaging center ensure your scan is quick and efficient.
How to Prepare:
- Follow any recommendations your doctor gives you. This may include specific directions for medication or fasting instructions, which helps minimize side effects of the contrast agent.
- If fasting—avoid eating or drinking 3–6 hours before the scan, or as specified by your doctor.
- Avoid wearing metal objects (e.g., jewelry, glasses, piercings).
- Inform the imaging center about:
- Allergies to iodine or contrast material.
- A history or present concern with kidney function.
- Current medications and pregnancy status.
Tip: Stay hydrated before and after the scan to support kidney function and help flush the contrast agent from your body.
What to expect during a CT scan with contrast
On the day of your head CT appointment, the helpful staff at your imaging center will guide you through the scan step by step, and your CT technologist will make sure that you’re as comfortable as possible. Let’s take a closer look at what happens during a head CT scan.
How is the contrast material administered for a CT scan?
In some head CT scans, contrast material is used to enhance the visibility of specific areas like the brain, blood vessels, or tissues.
It is commonly administered through an IV injection into a vein in your arm, allowing it to travel quickly through your bloodstream. Occasionally, contrast may be given orally.
A technologist or other medical professional will be with you during the scan, to monitor any side effects you may experience from the contrast.
What happens during a head CT scan? How long does it take?
During a head CT scan, you may be asked to change into a gown. You will lie down on a bed-like table that will slide into a doughnut-shaped scanner, which will rotate around you as it takes a series of X-rays from different angles.
When the contrast agent is administered you may feel a warm flush throughout your body or a metallic taste in your mouth.
The technologist may ask you to hold still and to hold your breath for a few seconds at selected intervals to make sure the images are clear. You will be able to communicate with the technologist at any time during the scan.
The scan itself may take about 15 minutes, but the entire appointment may take about an hour.
What can I expect after my head CT scan with contrast?
Right after your head CT scan, you may be monitored for a short period to ensure there are no serious side effects from the contrast agent.
Post-Scan Care: Drink plenty of water to flush the contrast from your system. Most people can resume normal activities right after the scan.
A radiologist will read the results of your scan, and share them with your healthcare provider, who will reach out to you to discuss your results.
What should I avoid doing after a CT scan with contrast?
After a head CT scan with contrast, most people can resume their normal activities without limitations. Make sure to follow your provider’s suggestions for what to avoid.
You should drink plenty of water to help flush the contrast agent from your body. If you experience any unusual symptoms, like rash, itching, or difficulty breathing, contact your healthcare provider immediately.
How to schedule an appointment with us
Reach out to us at American Health Imaging, and we’ll help you schedule an appointment at an imaging center near you, today.
We’re here to help you get the answers you need.
Frequently asked questions
Q: What can a head CT scan reveal about my brain, skull, and blood vessels?
A: A head CT scan provides detailed images of your brain, skull, and blood vessels to help detect issues like injuries, infections, or abnormalities.
Q: What is contrast material, and how does it improve the results of a head CT scan?
A: Contrast material is a special dye that enhances the visibility of blood vessels, tissues, and certain abnormalities on a head CT scan.
Q: Is a head CT scan with contrast safe?
A: Yes, for most people. Inform your provider of any allergies or kidney concerns to ensure safety.
Q: How does my healthcare provider determine if I need contrast for my head CT scan?
A: Your healthcare provider evaluates your medical condition and symptoms to decide whether contrast is necessary for a clearer diagnosis.
Q: What conditions can a head CT scan with contrast help to diagnose?
A: A head CT scan with contrast can help diagnose strokes, tumors, aneurysms, and other abnormalities in the brain and blood vessels.
Q: How should I prepare for a head CT scan with contrast?
A: You may need to fast for a few hours before the scan and inform the imaging center about any medical conditions or allergies.
Q: What should I tell the imaging center about my medical history before a head CT with contrast?
A: It’s important to disclose any history of kidney issues, allergies to contrast dye, or previous reactions to imaging tests.
Q: How is the contrast material administered for a CT scan?
A: Contrast material is typically administered through an intravenous (IV) injection, which allows it to circulate and highlight specific areas.
Q: What can I expect after my head CT scan with contrast?
A: After the scan, you can usually resume normal activities, but you may be advised to drink water to help flush the contrast from your body.
Q: How soon will I get my results?
A: A radiologist reviews the images, and your healthcare provider typically receives the results within 24–48 hours.