Diagnosing Migraine with Aura – New Criteria

Following up on the report about the new International Classification of Headache Disorders 3rd edition (ICHD-3), one of the most interesting changes, though a little technical, was the change in the diagnostic criteria for migraine with aura. This is to say, new more precise ways of diagnosing migraine with aura (MA).

There are many types of migraine, of course, and also many types of migraine with aura. When the beta edition of ICHD-3 came out several years ago, there was concern that MA could be confused with transient ischaemic attacks, or mini-strokes. This is one reason why more specific details were added to the definition.

So let’s take a quick look.

First, in order to actually be diagnosed with MA, you need to have more than one attack. That hasn’t changed. Also, it’s still possible that you could fit the criteria below, but you better fit a different diagnosis.

Next, you obviously need to experience an “aura”. In migraine, aura is something temporary, or “reversible”. Possible aura types include:

• visual (such as seeing flashing lights or patterns)
• sensory (often a “tingling” sensation)
• speech and/or language (such as slurred speech)
• motor (weakness)
• brainstem (various specific auras, including vertigo or impaired hearing)
• retinal (for example, vision loss in one eye)

We won’t get into the details of all of these. Some of these will help doctors diagnose what type of MA you have – remember, there are several sub-types. All you need is one of these symptoms to receive the MA diagnosis.

It’s interesting that these symptoms usually come in a predictable order, as the migraine chain-reaction spreads.

Finally, to be diagnosed with MA you must have at least three of the following six characteristics:

• At least one aura symptom spreads gradually over 5 minutes or more.
• Two or more aura symptoms occur in succession (has this ever happened to you? It’s probably more common than you think. This was added for clarification since the beta version.)
• Each individual aura symptom lasts 5-60 minutes (so, yes, auras could last several hours if there are several auras. Note that motor symptoms are an exception – they could last for 2-3 days.)
• At least one aura symptom is unilateral – on only one side.
• At least one aura symptom is positive (for example, seeing flashing lights is positive, partial blindness is negative.)
• The aura is accompanied, or followed within 60 minutes, by headache (presumably the aura ends, and then within 60 minutes there’s a headache. Or they overlap.

Note that these are aura symptoms, not prodrome symptoms. The difference is that the prodrome may start hours or even a day or two before the attack. It’s often less defined, but may include feeling tired or “heavy”, or having neck stiffness, or having unusual trouble concentrating.

Many of the above symptoms are shared with transient ischaemic attack (TIA), but it’s hoped that the specific details will help rule out TIA. The key symptom of TIA is one-sided weakness or numbness, although other symptoms such as vertigo or vision loss are not uncommon. Learn more about transient ischaemic attack here.

Of course, in either case, it’s best to see a neurologist who can confirm a diagnosis for you, and help you avoid even more serious problems down the road.

For details about various types of migraine with aura, click through the list here.