Migraine with Brainstem Aura

Migraine with brainstem aura (MBA) is characterized by recurring attacks of certain temporary symptoms that are believed to originate in the brainstem. The brainstem is located at the base of the brain and connects to the top of the spinal cord; its function is to help regulate the two-way channel of communication between the brain and the body. Until 2013, MBA was known as “basilar-type migraine.” In the updated version of the International Headache Society’s guidelines – The International Classification of Headache Disorders, 3rd Edition (ICHD-III) – it was renamed “migraine with brainstem aura” because research now suggests that the basilar artery in the brain is not involved in causing its symptoms, as had previously been thought.1

The ICHD-III classifies MBA as a sub-type of the broader category of migraine with aura, which was also revised in the newest guidelines to include MBA and three other sub-types: migraine with typical aura (MTA), hemiplegic migraine, and retinal migraine. MTA is the most common of those four, with MBA and the others being relatively rare. While researchers are unsure about precisely how many people have MBA worldwide, a 2006 study of 362 patients with MTA in Denmark reported that about 1 in 10 of those patients also had MBA.2 Another study in China in 2011 found that 6.6% (23/348) of MTA patients had also experienced MBA attacks.3 In both studies, there were about 4 times as many women with MBA than men. Most people are initially diagnosed with MBA as teenagers or young adults.

Symptoms of migraine with brainstem aura

The ICHD-III defines a specific set of brainstem aura that are experienced as symptoms during MBA attacks:

  • Vertigo is a type of dizziness described as the feeling that the body or surrounding environment is spinning or tilting, even though both are actually stationary.
  • Dysarthria refers to difficulty controlling the speech-producing muscles (mouth, tongue, larynx, etc) resulting in slurring, mumbling, and general difficulty in producing sounds and words.
  • Tinnitus, or “ringing in the ears,” is the perception of noise (buzzing, humming, ringing, whistling, etc) in one or both ears that originates from inside the body, not from an external source.
  • Hypacusis refers to general hearing impairment.
  • Diplopia (“double vision”) is the visual perception of two simultaneous images of the same single object.
  • Ataxia is a lack of muscle coordination when trying to intentionally move the limbs, head, or body.
  • A decreased level of consciousness results in disorientation, lack of awareness, and/or inability to remain alert.

In the 2006 Danish study, the most frequently reported brainstem aura were vertigo (61%), dysarthria (53%), tinnitus (45%), and diplopia (45%); most patients reported experiencing two or three brainstem symptoms.2

Almost all MBA patients also have typical aura symptoms during some or all MBA attacks, and the majority also experience separate attacks of migraine with typical aura but no brainstem symptoms.2 So-called “typical aura” are common types of visual, sensory, and speech/language symptoms that can occur prior to or during the headache phase (only rarely does MBA occur without headache). Visual aura, the most frequently reported type, are temporary disturbances to the field of vision that can include blind or bright spots spreading outward from a central point, crescents or C-shapes with shimmering edges, blurred vision, moving zigzag lines or shapes, seeing spots or stars, or flashing/flickering light. Sensory aura are often described as a pins-and-needles sensation that spreads over one side of the body. Speech/language symptoms can include problems with word recall, language comprehension, and writing.

Diagnosing migraine with brainstem aura

According to the ICHD-III, to be diagnosed with MBA a patient must have experienced at least two migraine attacks, each involving two or more brainstem aura plus at least one typical aura. The attacks must also include at least two of the following characteristics:

  • At least one aura symptom spreads gradually over at least five minutes, and/or two or more symptoms occur one after the other.
  • Each aura symptom lasts between 5-60 minutes.
  • At least one aura symptom occurs on only one side of the body.
  • Aura is accompanied by headache, or headache follows within an hour.

Because so many patients with MBA also experience separate migraine attacks with typical aura only, the ICHD-III allows patients to be diagnosed with MBA as well as MTA (ie, the two diagnoses are not exclusive). If the only brainstem symptom experienced during the attack is vertigo, then the appropriate ICHD-III classification is “vestibular migraine” rather than MBA. A diagnosis of hemiplegic migraine is appropriate if the migraine attack includes motor aura such as muscle weakness or paralysis on one side of the body.

Treating migraine with brainstem aura

The experience of brainstem aura symptoms can be very distressing and frightening, particularly when they happen for the first time. The symptoms may even cause secondary symptoms like anxiety and hyperventilation, which can make the primary brainstem symptoms more susceptible to misinterpretation or misdiagnosis. This is an important concern regarding MBA, because the brainstem aura can appear very similar to the symptoms of serious disorders such as epilepsy, stroke, or transient ischemic attack (a brief blockage of blood flow in part of the brain that often occurs before major stroke). For this reason, it is very important to seek medical attention promptly the first time these brainstem symptoms occur, or if there is a change in symptom frequency or severity. In some cases clinicians may recommend an EEG, MRI, or CT scan to find out for sure what is causing the symptoms.

For more than thirty years, there have been worries about treating MBA with drugs containing triptans, which are often prescribed as pain relievers for other types of migraine with aura. It was previously believed that the brainstem aura symptoms were caused by constriction in the basilar artery that reduces blood flow. Because triptans are also associated with narrowing of the blood vessels, there was concern that this double effect would not be safe for patients with MBA. In fact, the US Food and Drug Administration does not allow MBA patients to take part in clinical trials for triptans and recommends that those drugs should not be prescribed to MBA patients. But now that researchers think that MBA aura symptoms do not actually originate from the basilar artery, many believe that the use of triptans should be approved for those patients. But because MBA patients have not been allowed to participate in clinical trials, the safety and effectiveness of triptan treatment for MBA has not yet been confirmed due to lack of data.4 This is an important opportunity for future research that may provide an additional option for relief of pain caused by MBA.

Treatments other than triptans that are currently recommended for MBA are similar to those for other types of migraine with aura, including NSAID pain relievers and anti-nausea drugs during the acute phase and preventive medications for people who suffer from frequent attacks.

Written by Anna Nicholson | Last reviewed: November 2014.
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