Headache testing relies on the history and physical exam to determine what tests are necessary. This may include a CT scan, MRI, or lumbar puncture.
There are several different types of headaches, and they can have many causes. The type of treatment you need depends on the type of headache you’re having. This is why it’s important for your doctor to determine which type of headache you’re having, so you can get treatment that works for you.
Testing for your headaches may include some of all of the following:
• Headache history and physical exam
• Headache diary
• Imaging studies (X-ray, CT scan or MRI)
• Blood tests
• Lumbar puncture
The most important part of the process for diagnosing the cause of your headaches is the history and physical exam. Your doctor will ask detailed questions about your headaches, including how often they happen, what they feel like, what other symptoms are associated with them, what types of events occur before the headaches, and other factors.
Your prior medical history will also be important, and your doctor will do a physical exam. Some of the important parts of this exam include the neurological exam (in which your doctor checks for any signs of damage in your neurological system), eye exam (in which your doctor looks into your eyes to check for signs of increased pressure or other damage), and your vital signs (temperature, pulse, breathing, and blood pressure). Depending on what your doctor finds on the history and physical exam, he or she will decide what other tests would be useful in figuring out the cause of your headaches.
In many cases, it can be difficult to recall all of the factors surrounding a headache weeks later. That’s why keeping a headache diary can be so helpful. By recording each of your headaches, and what happened in the period before them (what you were doing, when and what you had eaten, how much you slept, and other factors), you and your doctor may be able to find patterns in the occurrence of your headaches, giving clues about how best to treat them.
If your doctor believes that a structural abnormality in your head or brain may be causing your headaches, then he or she may order imaging studies. A special X-ray series can be used to look at your sinuses, to determine whether a chronic sinus infection is the cause. A CT scan or MRI of your brain can look for problems such as a tumor that could be the cause of your headaches.
Blood tests can sometimes provide useful information for diagnosing your headache. Urine tests may also be used. For instance, your doctor may want to check for signs of diabetes, because abnormal blood sugar can cause headaches. An abnormality in your white blood cell count could indicate an infection that is causing them.
If your doctor suspects that an infection is causing your headaches, then he or she may order a lumbar puncture. This is a test in which a small needle is inserted into your lower back to withdraw some of the fluid that surrounds your brain and spinal cord. The fluid can then be tested for infections and other abnormalities.
National Institute of Neurological Disorders and Stroke (NINDS). “NINDS Headache Information Page.” NINDS website (2015). http://www.ninds.nih.gov/disorders/headache/headache.htm
Mayo Clinic Staff. “Migraine: Tests and diagnosis.” Mayo Clinic website (2013). http://www.mayoclinic.org/diseases-conditions/migraine-headache/basics/tests-diagnosis/con-20026358
Mayo Clinic Staff. “Tension headache: Tests and diagnosis.” Mayo Clinic website (2013). http://www.mayoclinic.org/diseases-conditions/tension-headache/basics/tests-diagnosis/con-20014295