Did you know that 97% to 99% of CT scans for headache turn up normal? This is why medical societies such as the American Academy of Family Physicians, the American Academy of Neurology and the American Headache Society have, for a long time, recommended against routine use of CT and MRI scans for headaches and emphasized the value of neurologic exams instead. Their guidelines were drafted and put under doctors’ noses back in the year 2000. But we’re now learning that use of CT and MRI for headache—despite their ineffectiveness, cost and (in the case of CT scans) radiation—has substantially increased instead of decreased over time.
What gives…and who’s to blame?
Imaging tests for headaches here in the US cost $1 billion each year. If they were helpful and necessary, the money would be well-spent, but the only patients who may need a CT scan or MRI if headache is the main complaint are folks whose neurological examination—a physical exam preferably done by a neurologist—detects warning signs of a tumor or blood clot, for example, that an imaging test could confirm. What has been happening, though, is that doctors are increasingly sending patients who complain of easily diagnosed tension headaches and migraines for CT scans and MRIs.
This costly habit was uncovered in a recent study that spurred a call for doctors to know and stick to the guidelines. The study researchers used information on outpatient care from a special database called the National Hospital Ambulatory Medical Care Survey to identify headache diagnoses and use of CT or MRI. The analysis showed that the rate of CT and MRI use to investigate headache and migraine tripled from 5% to 15% between 1995 and 2010, suggesting ongoing and worsening overuse of imaging technology.
REASONS FOR OVERUSE
Further research is needed to sort out why CT scans and MRIs appear to be overused in people complaining of headache or migraine. In certain instances, it may be because the doctor is sincerely trying to get to the root of the problem. In others, it is because the doctor is concerned that if a health emergency occurs later, a patient’s lawyer will cry negligence if a CT or MRI was not done. In other instances, it may be because the doctor has a financial interest in having imaging done…and, in others, it may be because a patient bugged his or her doctor so much for a CT or MRI scan that the doctor simply capitulated against his better professional judgment.
WHEN IMAGING IS WARRANTED
If a thorough neurological exam, which looks at reflexes, coordination and motor strength (gripping, walking on heels), among other signs of neuromuscular health, is abnormal and your headache can’t be diagnosed based on your symptoms, an imaging test might be needed, according to the year 2000 guidelines. Headaches that might be worrisome and require a look-see from imaging, according to the American Headache Society and American College of Radiology, are those that are either very different from headaches you normally have (if you are headache-prone) or those that come on very suddenly and severely, including those that come after exertion. In addition, a headache that comes with a constellation of symptoms that include fever, seizures, vomiting, loss of coordination or a change in vision, speech and alertness is a cause for immediate medical attention that will likely include a CT or MRI scan.
But if you are simply prone to headaches, before asking your doctor to order an imaging study—or blindly agreeing to his or her recommendation to have one done—you might want to check out the patient resources page of the American Headache Society or ask your doctor for a referral to a headache-management specialist, a type of neurologist who can provide counseling about headache as well as both drug and nondrug strategies for headache and migraine relief. This list of five things physicians and patients should question from the American Headache Society may be very useful if you want to learn more about whether and when you need an CT scan or MRI because of headaches.