Doctor on Call
Jennifer, a 37-year-old accountant from Lancaster, Pennsylvania writes:
About 5 years ago I began having a problem with sick headaches for the first time since I was a teenager, and over the last 2 years my headaches have become much worse. I had a headache last week that lasted for days and was so excruciating that I was unable to work and had to cancel my daughter’s birthday party on Sunday. When I saw our family doctor the next day, I told her that I needed an MRI scan because there had to be something wrong in my brain. She told me that my headaches were “just migraine” and that a scan was not needed. I told her that my grandmother had died from a brain aneurysm, but she still didn’t seem particularly concerned. Is she simply not hearing me? Do I need to see an aneurysm specialist?
The Doctor’s Reply
While it’s entirely reasonable for you to seek help in diagnosing and managing your headaches disorder, what you describe is quite consistent with migraine. Even with your grandmother’s history of a fatal ruptured brain aneurysm, the likelihood of your having an aneurysm is quite low. Approximately 2% of the adult population has a cerebral aneurysm, and thankfully only a small percentage of those aneurysms will rupture or otherwise become symptomatic. Having a second-degree relative with a history of a ruptured aneurysm conveys such a slight risk you will suffer the same that a screening diagnostic imaging study is not considered to be useful.
Even if you do have an aneurysm, it is not what is causing your history of recurrent headaches occurring over a period of years. Aneurysms most commonly are congenital, present from birth, and in a minority of cases they may asymptomatically enlarge over time and then suddenly rupture. If rupture occurs, the most common presentation is an isolated “thunderclap” headache which often is associated with physical exertion. Almost always, it is a one-time event; it would be extremely unusual for an aneurysm to cause recurrent headache over an extended period of time.
That said, many patients with migraine will undergo brain MRI, and simply by the odds a small percentage of those scans will demonstrate an asymptomatic, incidental brain aneurysm. In most cases the aneurysm is best left alone, as the risk of harm from surgical or catheter-based elimination of the aneurysm outweighs the benefit of such intervention. Put another way, the annual risk of a small aneurysm rupturing is so low that it’s difficult for any intervention to reliably beat those odds. Experts in the area of aneurysm management typically recommend simply following these incidental aneurysms with a noninvasive imaging study (e.g., MRA=magnetic resonance angiography) to confirm that the aneurysm is not enlarging in size.
As was emphasized in the Spring 2019 issue, if your history is consistent with migraine and your neurologic examination is normal, the likelihood that brain MRI or other diagnostic testing will yield a result that changes your diagnosis and management is extremely small. What you need and deserve are adequate education regarding migraine and an appropriate treatment strategy…not an unnecessary test.