According to Brain Research UK, 2 in 5 UK adults (more than 20 million people) are affected by a headache or facial pain disorder.

Sometimes, headaches can pass quickly on their own, and won't recur. However, persistent headaches, including migraine headaches and cluster headaches, can be symptoms of a more serious problem. Headache and facial pain disorders are responsible for almost 3/4 of neurological-related disabilities, which include stroke, brain injury or more progressive conditions such as dementia.

Many patients who experience unusual headaches feel anxious about the possible causes. This article will talk you through the different types of headaches, how headaches happen, and when it's time to book a brain scan to find out if there is a serious underlying cause.

What are the different types of headaches?

There are over 100 different types of headaches, and it is difficult to know which one you are suffering from. However, most headaches can be grouped into two different types, primary headaches and secondary headaches.

What is a primary headache?

A primary headache is a type of headache that is not caused by another underlying condition. Primary headaches can be further divided into categories, such as tension headaches, cluster headaches, and migraine headaches.

What are tension headaches?

Tension headaches are the most common type of primary headache, accounting for around 90% of all cases. They are usually described as a dull, throbbing pain that affects the forehead, temples or both sides of the head. Tension headaches can be triggered by eye strain, stress, anxiety, tiredness and lack of sleep, or poor posture.

What are cluster headaches?

Cluster headaches are a rare type of primary headache that can be very painful. They are usually described as a sharp, burning pain that affects one side of the head. Cluster headaches often occur in series, with one headache lasting for a few days followed by a period of remission. Cluster headaches can be triggered by alcohol, cigarette smoke, bright lights or changes in the weather.

What are migraine headaches?

Migraine headaches are the second most common type of primary headache, affecting around 1 in 4 people. They are usually characterised by throbbing pain on one side of the head, accompanied by nausea, vomiting and sensitivity to light and sound. Migraine headaches can be triggered by stress, hormonal changes or even certain foods.

What is a secondary headache?

A secondary headache is caused by another underlying condition. Examples of secondary headaches include cranial nerve headaches and systemic headaches.

What are cranial nerve headaches?

Cranial nerve headaches are a type of secondary headache that is caused by damage or compression to one of the 12 cranial nerves. They can be caused by a number of different conditions, including head injury, stroke, tumour or infection.

What are systemic headaches?

Systemic headaches are secondary headaches caused by another underlying condition that affects the entire body. Systemic conditions that can cause headaches include high blood pressure, kidney disease, diabetes and auto-immune diseases.

Do I need a brain scan?

Imaging tests such as MRI or CT scans can be used to identify whether your headaches are caused by issues in your central nervous system, and can also be used to identify or evaluate whether you have a brain tumour.

However, some types of secondary headaches may be caused by problems elsewhere in the body, and there may be other serious symptoms. At Scan.com, our experienced clinical team reviews all referrals to make sure the correct scan has been chosen. If your brain imaging tests reveal no anomalies, you may need to have more tests to identify whether the headache is caused by other factors.

For patients having brain scans elsewhere, it is important to speak to a healthcare professional about possible symptoms that could be causing a severe headache, to ensure nothing is missed.

Difference between CT scan and MRI for headaches

Both CT and MRI scans can be used to diagnose or rule out some causes of headaches, and each has its own advantages and disadvantages. In some cases, based on your medical history, you might be recommended one over the other, either to reduce unnecessary radiation exposure or avoid the effects of MRI magnets on metal or devices in your body. Scan.com's experienced clinical team will provide guidance after you place your booking, to ensure you've selected the correct scan for your needs.

What can an MRI scan for headaches show?

MRI stands for magnetic resonance imaging, and is an imaging test used to diagnose diseases and medical issues. MRI uses strong magnets and radio waves to create detailed images of the soft tissues and musculoskeletal system, and can show both the brain and spinal cord. MRI also allows you to avoid unnecessary radiation with generally no harmful effects.

An MRI scan can't diagnose a headache, but as a neurological exam, it can investigate the underlying causes or why your headache occurs.

An MRI scan for headache can identify:

a brain infection, called an abscess
excess fluid (hydrocephalus) in the brain
Spinal cord problems, including a herniated disc
a stroke
a brain injury
signs of a brain tumour

All of these problems could be the causes of a headache.

MRI scan for migraine

As for a headache, MRI cannot diagnose migraines in and of themselves but it can help spot other medical conditions that could be causing migraine symptoms, such as tumours, abscesses, or hydrocephalus (fluid in the brain). They can also identify structural changes in the brain that may need further investigation.

What does a CT scan show for headaches?

CT stands for computerised or computed tomography. It uses x rays to generate images of the head and brain. A CT scan can show some of the causes of headaches, such as excess fluid in the brain (called hydrocephalus), an abscess (infection of the brain), tumours, sinus blockages or even an aneurysm or bleeding on the brain. However, a CT scan often provides less detailed pictures of the soft tissues than MRI.

If you have an aneurysm clip in your brain, or certain types of pacemaker, healthcare providers would normally advise you to have a CT scan rather than an MRI. This is because the magnets in an MRI machine can interact and interfere with medical devices and metallic objects.

CT scan for migraines

Using CT scan for migraine investigations is similar to using an MRI scan for migraines - they would not diagnose a migraine but may reveal why migraines are occurring. A brain scan for migraines can reveal underlying conditions like sinus blockages, brain bleeds, tumours and stroke which may cause headache or migraine pain.

Do I need contrast material for a head and brain scan?

Some patients may need to have contrast material injected into their veins to help make the images on a brain MRI or CT scan clearer. This is because the contrast material helps to highlight the blood vessels and some tissues in higher definition.

If your healthcare professional feels that you would benefit from having contrast material injected, they will discuss this with you prior to your scan.

MRI migraine brain vs normal brain - what do the images look like?

MRI images are black and white, highly detailed pictures. People who have migraine may notice white spots or areas on their brain images, which could be linked to irregularity in the white matter tissues, which are mostly made up of nerves. These white spots are more common in people who have migraine with aura.

However, everyone has brain lesions, especially as we age. They are not always cause for concern, and your radiologist will advise in their report if any further treatment or investigation is required.

Why do I have a headache after MRI?

MRI scans are generally safe for most people, with limited side effects. However, if you have had a gadolinium contrast agent injection, a common side-effect is getting a headache. This should pass shortly after your scan, and may be accompanied by dizziness and nausea. MRI scans are also very noisy procedures. As the magnets within the scanner are turned on and off, they emit loud clanging noises, buzzing, and even beeping noises. You will usually be given headphones to reduce the level of noise, but some people might find that if they are sensitive to noise, MRI can cause headaches after the procedure.

Next steps:

Book your brain MRI or CT scan to get the answers you need. It's more affordable than you might think, and we offer flexible payment options via Splitit and Paypal.
Check out our news page to discover more about scans, radiology and symptoms.

Sources used:

https://www.brainresearchuk.org.uk/neurological-conditions/headache-and-facial-pain
https://www.webmd.com/migraines-headaches/making-diagnosis-mri
https://www.webmd.com/migraines-headaches/making-diagnosis-ct-scan
https://my.clevelandclinic.org/health/diseases/8257-tension-type-headaches
https://www.mayoclinic.org/symptoms/headache/basics/causes/sym-20050800
https://my.clevelandclinic.org/health/diseases/9639-headaches

What’s Causing Your Headaches? A Head and Brain Scan Could Help You Find Out