Headaches: Should I Have Imaging Tests to Find Out What's Causing My Headaches?

You may want to have a say in this decision, or you may simply want to follow your doctor's recommendation. Either way, this information will help you understand what your choices are so that you can talk to your doctor about them.

Headaches: Should I Have Imaging Tests to Find Out What's Causing My Headaches?

1

Get the
Facts

2

Compare
Options

3

Your
Feelings

4

Your
Decision

5

Quiz
Yourself

6

Your Summary

Get the facts

Your options

Have a CT scan or MRI to look for the cause of your headaches.
Don't have these imaging tests.

Key points to remember

In most cases, an imaging test won't tell you what's causing your headaches.
Even when headaches are very painful, it's rare that they are caused by a serious medical problem.
Your doctor may order an imaging test to rule out uncommon but serious medical problems such as a brain tumour, a blood clot, or an infection.
Imaging tests won't help you manage your pain. And they may not change the type of treatment you get for your headaches unless they find a serious problem.

FAQs

What are the different types of headaches?

Most people get headaches from time to time. Most headaches are not serious. But they can be very painful, and you may get them often.

Cluster headaches can cause severe pain during cycles or "clusters" of headaches that happen over a period of weeks to months.
Migraine headaches can cause a throbbing pain that usually starts on one side of your head. When you have one of these headaches, you may also feel sick to your stomach; vomit; and notice that you're more sensitive to light, noise, and certain smells.
Tension headaches can cause a constant ache, tightness, and pressure around your forehead, temples, or the back of your head and neck. It may feel like your head is in a vise.

It's rare that a headache is caused by a serious medical problem.

Most people can treat their headaches with pain relievers that they buy without a prescription, like acetaminophen (such as Tylenol) or ibuprofen (such as Advil). But others may need a prescription for stronger pain medicine to help them feel better.

What types of imaging tests can be used to find out what's causing your headaches?

There are two imaging tests that can be used to evaluate your headaches:

A CT scan uses X-rays to make detailed pictures of the inside of your head. During the test, your body is positioned so that your head is inside the CT scanner, which is a large doughnut-shaped machine. The test usually takes only a few minutes.
An MRI is a test that uses a magnet and radio waves to make detailed pictures of the inside of your head. It gives more information than X-rays or a CT scan. During the test, you lie inside a machine that has a strong magnet. The test usually takes 30 to 60 minutes.

Keep in mind that having an imaging test won't help you manage your pain. And it may not change the type of treatment you get for your headaches unless it finds a more serious problem.

In most cases, you won't need to have an imaging test to look for the cause of your headaches. Doctors can usually make a diagnosis and recommend treatment based on your symptoms and by doing a physical examination. Your doctor may order one of these tests to rule out uncommon but serious medical problems such as a brain tumour, a blood clot, an infection, or a bulge (called an aneurysm) in the wall of a blood vessel in your brain. But most headaches aren't caused by these more serious problems.

When headaches are a sign of a more serious medical problem or a head injury, you may have other symptoms along with your headache. You may vomit, feel dizzy or weak, or have numbness and tingling. Or you may have problems with your vision and coordination.

What are the risks from having an imaging test?

The risks from having a CT scan or an MRI are small.

During a CT scan, you're briefly exposed to radiation. There is a small risk of developing cancer from exposure to the X-rays used in CT scans. The risk is higher in children, young adults, and people who have many radiation tests. But the benefits of the test results are usually greater than the risk of radiation from a CT scan. If you are concerned about this risk, talk to your doctor and confirm that the test is needed. If you're pregnant, a CT scan is usually not a good choice, because there is a chance that the baby might be harmed by the radiation.

An MRI doesn't use radiation. And there are no known harmful effects from the magnetic field used during the scan. But the magnet is powerful and may affect certain medical devices such as pacemakers and metal objects such as heart valves, brain clips, and ear implants.

Sometimes a dye (contrast material) may be used during a CT scan or MRI. This can make the blood vessels and certain types of tissue (such as tumours) in your brain easier to see. There is a slight chance that you may have an allergic reaction to the dye. But most reactions are mild and can be treated with medicine.

Why might your doctor recommend an imaging test?

Your doctor may advise you to have an imaging test if:

You have sudden, severe pain, and it feels like the worst headache you have ever had.
Your headaches have gotten worse.
You have other symptoms along with your headaches, such as dizziness, weakness, vision changes, numbness, tingling, and problems with coordination.
You are older than age 50 and your headaches are different from when you were younger.
You have severe headaches that wake you up at night or in the morning.
Your headaches occur during or after exercise or sex, or when you cough or sneeze.

Compare your options

Compare


What is usually involved?
What are the benefits?
What are the risks and side effects?

Have an imaging test Have an imaging test

During a CT scan:
- You will lie very still on a table that moves slightly while the scanner takes pictures. You may hear a click or buzz as the table and scanner move.
- Your head may be held with a strap to help you lie still, but your face won't be covered.
- A dye may be injected into your vein to make certain types of tissue easier to see.
During an MRI scan:
- You lie inside a special machine that has a strong magnet.
- Your head, chest, and arms may be held with straps to help you lie still. A coil may be placed over or wrapped around your head.
- You may hear a fan and feel air moving. You may also hear tapping or snapping noises as the MRI takes pictures.
- A dye may be injected into your vein to make certain types of tissue easier to see.

Imaging tests can rule out a serious medical problem such as a brain tumour, a blood clot, an infection, or an aneurysm.
A normal test result can reassure you that nothing serious is causing your headaches.

You might have an allergic reaction to a dye that may be used during the test.
If you have a CT scan, you'll be exposed to a small amount of radiation.

Don't have an imaging test Don't have an imaging test

You keep taking medicines to manage your headaches.
You keep avoiding the things that cause your headaches (triggers).
You keep a headache diary. This can help you find a pattern to your headaches and see if treatment is working.
You make other lifestyle changes to help prevent headaches (such as sleeping well or managing stress).

If your symptoms don't improve with medicine, you can decide later to have an imaging test to look for the cause of your headaches.
You avoid being exposed to radiation or having a possible allergic reaction to a dye that may be used during the test.

Your headaches might be caused by a serious medical problem that needs to be treated right away, and you won't know it.

Personal stories about imaging tests for evaluating headaches

These stories are based on information gathered from health professionals and consumers. They may be helpful as you make important health decisions.

I started having headaches a few months ago, seems like out of the blue. The pain is usually on one side of my head, although it can spread to my whole head. Light hurts my eyes, and sound and quick body movements make the headaches worse. Sometimes I feel nauseous. The headaches go away in a few hours, but I feel exhausted for several days after the pain stops. My doctor said the headaches are probably migraines. She gave me some medicines to stop a migraine when it starts. I am going to try the medicines for a while and keep a headache diary to get a better idea of when my headaches occur and if there is anything (like certain foods) that might be triggering my headaches. I don't think I need imaging tests right now.

Amy, age 26

Headache pain started waking me up in the night a couple of months after I had a minor car accident. I didn't go to the hospital after my accident because I felt fine. The headache pain is pretty severe but doesn't stick around too long. Sometimes I feel tingling down my arm when I get a headache, and one side of my face feels numb. My vision gets a little blurry, too. I went to see my doctor, who recommended I have imaging tests to make sure I didn't injure my brain during the accident. I think I'll have the imaging tests to make sure nothing serious is causing my headaches.

Robert, age 52

A few hours after I went to sleep, I started waking up with extremely painful headaches that affect only one side of my head and face. My nose gets runny, and my eye waters and droops a little bit on the same side of my face. It feels like someone is sticking a hot poker in the side of my head. The headache pain usually stops in about 30 minutes, but then another one starts in an hour or two. I visited my doctor, and he said these are classic cluster headache symptoms. I think my dad had these headaches, too. I'm going to try the medicines the doctor gave me to stop the headaches and see what happens. My doctor and I discussed imaging tests, but neither of us thinks they are necessary right now. Even if I had the tests, my treatment wouldn't change.

Ramon, age 30

I had breast cancer a few years ago, but it went into remission after a long period of treatment. And all my follow-up tests have been cancer-free. I have been feeling pretty good for a few years now, but recently I started having headaches that make me really nauseous. I smell weird smells and sometimes I feel really spacey. Because of my history with cancer, my doctor thinks I should have imaging tests even though these may just be migraine headaches—I had a few migraines earlier in my life. My blood work keeps coming back normal, but I am really worried about what could be causing my headaches. I am going to have imaging tests just for reassurance that the cancer has not returned.

Lita, age 42

What matters most to you?

Your personal feelings are just as important as the medical facts. Think about what matters most to you in this decision, and show how you feel about the following statements.

Reasons to have an imaging test to find the cause of my headaches

Reasons not to have an imaging test

I'm worried that something serious might be causing my headaches.

I'm not worried that something serious might be causing my headaches.

More important

Equally important

More important

I'm not afraid to get a shot if a special dye is needed for the test.

I don't like getting shots.

More important

Equally important

More important

My other important reasons:

More important

Equally important

More important

Where are you leaning now?

Now that you've thought about the facts and your feelings, you may have a general idea of where you stand on this decision. Show which way you are leaning right now.

Having an imaging test

NOT having an imaging test

Leaning toward

Undecided

Leaning toward

Your Summary

Here's a record of your answers. You can use it to talk with your doctor or loved ones about your decision.

Your decision

Next steps

Which way you're leaning

How sure you are

Your comments

Your knowledge of the facts

Key concepts that you understood

Key concepts that may need review

Getting ready to act

Patient choices

What matters to you

Print Summary

Credits

Author	Healthwise Staff
Primary Medical Reviewer	Anne C. Poinier MD - Internal Medicine
Primary Medical Reviewer	Adam Husney MD - Family Medicine
Primary Medical Reviewer	Martin J. Gabica MD - Family Medicine
Primary Medical Reviewer	Kathleen Romito MD - Family Medicine
Primary Medical Reviewer	Colin Chalk MD, CM, FRCPC - Neurology

Headaches: Should I Have Imaging Tests to Find Out What's Causing My Headaches?

Here's a record of your answers. You can use it to talk with your doctor or loved ones about your decision.

Get the facts
Compare your options
What matters most to you?
Where are you leaning now?
What else do you need to make your decision?

1. Get the Facts

Your options

Have a CT scan or MRI to look for the cause of your headaches.
Don't have these imaging tests.

Key points to remember

In most cases, an imaging test won't tell you what's causing your headaches.
Even when headaches are very painful, it's rare that they are caused by a serious medical problem.
Your doctor may order an imaging test to rule out uncommon but serious medical problems such as a brain tumour, a blood clot, or an infection.
Imaging tests won't help you manage your pain. And they may not change the type of treatment you get for your headaches unless they find a serious problem.

FAQs

What are the different types of headaches?

Most people get headaches from time to time. Most headaches are not serious. But they can be very painful, and you may get them often.

Cluster headaches can cause severe pain during cycles or "clusters" of headaches that happen over a period of weeks to months.
Migraine headaches can cause a throbbing pain that usually starts on one side of your head. When you have one of these headaches, you may also feel sick to your stomach; vomit; and notice that you're more sensitive to light, noise, and certain smells.
Tension headaches can cause a constant ache, tightness, and pressure around your forehead, temples, or the back of your head and neck. It may feel like your head is in a vise.

It's rare that a headache is caused by a serious medical problem.

What types of imaging tests can be used to find out what's causing your headaches?

There are two imaging tests that can be used to evaluate your headaches:

A CT scan uses X-rays to make detailed pictures of the inside of your head. During the test, your body is positioned so that your head is inside the CT scanner, which is a large doughnut-shaped machine. The test usually takes only a few minutes.
An MRI is a test that uses a magnet and radio waves to make detailed pictures of the inside of your head. It gives more information than X-rays or a CT scan. During the test, you lie inside a machine that has a strong magnet. The test usually takes 30 to 60 minutes.

Keep in mind that having an imaging test won't help you manage your pain. And it may not change the type of treatment you get for your headaches unless it finds a more serious problem.

What are the risks from having an imaging test?

The risks from having a CT scan or an MRI are small.

Why might your doctor recommend an imaging test?

Your doctor may advise you to have an imaging test if:

You have sudden, severe pain, and it feels like the worst headache you have ever had.
Your headaches have gotten worse.
You have other symptoms along with your headaches, such as dizziness, weakness, vision changes, numbness, tingling, and problems with coordination.
You are older than age 50 and your headaches are different from when you were younger.
You have severe headaches that wake you up at night or in the morning.
Your headaches occur during or after exercise or sex, or when you cough or sneeze.

2. Compare your options

	Have an imaging test	Don't have an imaging test
What is usually involved?	During a CT scan: You will lie very still on a table that moves slightly while the scanner takes pictures. You may hear a click or buzz as the table and scanner move. Your head may be held with a strap to help you lie still, but your face won't be covered. A dye may be injected into your vein to make certain types of tissue easier to see. During an MRI scan: You lie inside a special machine that has a strong magnet. Your head, chest, and arms may be held with straps to help you lie still. A coil may be placed over or wrapped around your head. You may hear a fan and feel air moving. You may also hear tapping or snapping noises as the MRI takes pictures. A dye may be injected into your vein to make certain types of tissue easier to see.	You keep taking medicines to manage your headaches. You keep avoiding the things that cause your headaches (triggers). You keep a headache diary. This can help you find a pattern to your headaches and see if treatment is working. You make other lifestyle changes to help prevent headaches (such as sleeping well or managing stress).
What are the benefits?	Imaging tests can rule out a serious medical problem such as a brain tumour, a blood clot, an infection, or an aneurysm. A normal test result can reassure you that nothing serious is causing your headaches.	If your symptoms don't improve with medicine, you can decide later to have an imaging test to look for the cause of your headaches. You avoid being exposed to radiation or having a possible allergic reaction to a dye that may be used during the test.
What are the risks and side effects?	You might have an allergic reaction to a dye that may be used during the test. If you have a CT scan, you'll be exposed to a small amount of radiation.	Your headaches might be caused by a serious medical problem that needs to be treated right away, and you won't know it.

Personal stories

Personal stories about imaging tests for evaluating headaches

These stories are based on information gathered from health professionals and consumers. They may be helpful as you make important health decisions.

"I started having headaches a few months ago, seems like out of the blue. The pain is usually on one side of my head, although it can spread to my whole head. Light hurts my eyes, and sound and quick body movements make the headaches worse. Sometimes I feel nauseous. The headaches go away in a few hours, but I feel exhausted for several days after the pain stops. My doctor said the headaches are probably migraines. She gave me some medicines to stop a migraine when it starts. I am going to try the medicines for a while and keep a headache diary to get a better idea of when my headaches occur and if there is anything (like certain foods) that might be triggering my headaches. I don't think I need imaging tests right now."

— Amy, age 26

"Headache pain started waking me up in the night a couple of months after I had a minor car accident. I didn't go to the hospital after my accident because I felt fine. The headache pain is pretty severe but doesn't stick around too long. Sometimes I feel tingling down my arm when I get a headache, and one side of my face feels numb. My vision gets a little blurry, too. I went to see my doctor, who recommended I have imaging tests to make sure I didn't injure my brain during the accident. I think I'll have the imaging tests to make sure nothing serious is causing my headaches."

— Robert, age 52

"A few hours after I went to sleep, I started waking up with extremely painful headaches that affect only one side of my head and face. My nose gets runny, and my eye waters and droops a little bit on the same side of my face. It feels like someone is sticking a hot poker in the side of my head. The headache pain usually stops in about 30 minutes, but then another one starts in an hour or two. I visited my doctor, and he said these are classic cluster headache symptoms. I think my dad had these headaches, too. I'm going to try the medicines the doctor gave me to stop the headaches and see what happens. My doctor and I discussed imaging tests, but neither of us thinks they are necessary right now. Even if I had the tests, my treatment wouldn't change."

— Ramon, age 30

"I had breast cancer a few years ago, but it went into remission after a long period of treatment. And all my follow-up tests have been cancer-free. I have been feeling pretty good for a few years now, but recently I started having headaches that make me really nauseous. I smell weird smells and sometimes I feel really spacey. Because of my history with cancer, my doctor thinks I should have imaging tests even though these may just be migraine headaches—I had a few migraines earlier in my life. My blood work keeps coming back normal, but I am really worried about what could be causing my headaches. I am going to have imaging tests just for reassurance that the cancer has not returned."

— Lita, age 42

3. What matters most to you?

Your personal feelings are just as important as the medical facts. Think about what matters most to you in this decision, and show how you feel about the following statements.

Reasons to have an imaging test to find the cause of my headaches

Reasons not to have an imaging test

I'm worried that something serious might be causing my headaches.

I'm not worried that something serious might be causing my headaches.

More important

Equally important

More important

I'm not afraid to get a shot if a special dye is needed for the test.

I don't like getting shots.

More important

Equally important

More important

My other important reasons:

More important

Equally important

More important

4. Where are you leaning now?

Now that you've thought about the facts and your feelings, you may have a general idea of where you stand on this decision. Show which way you are leaning right now.

Having an imaging test

NOT having an imaging test

Leaning toward

Undecided

Leaning toward

Credits

By	Healthwise Staff
Primary Medical Reviewer	Anne C. Poinier MD - Internal Medicine
Primary Medical Reviewer	Adam Husney MD - Family Medicine
Primary Medical Reviewer	Martin J. Gabica MD - Family Medicine
Primary Medical Reviewer	Kathleen Romito MD - Family Medicine
Primary Medical Reviewer	Colin Chalk MD, CM, FRCPC - Neurology

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