|1.2||Migraine with aura||G43.1|
|Previously used terms||Classic or classical migraine, ophthalmic, hemiparaesthetic, hemiplegic or aphasic migraine, migraine accompagnée, complicated migraine|
|Coded elsewhere||13.17 Ophthalmoplegic "migraine"|
Recurrent disorder manifesting in attacks of reversible focal neurological symptoms that usually develop gradually over 5-20 minutes and last for less than 60 minutes. Headache with the features of migraine without aura usually follows the aura symptoms. Less commonly, headache lacks migrainous features or is completely absent.
- At least 2 attacks fulfilling criterion B
- Migraine aura fulfilling criteria B and C for one of the subforms 1.2.1-1.2.6
- Not attributed to another disorder1
- History and physical and neurological examinations do not suggest any of the disorders listed in groups 5-12, or history and/or physical and/or neurological examinations do suggest such disorder but it is ruled out by appropriate investigations, or such disorder is present but attacks do not occur for the first time in close temporal relation to the disorder.
The aura is the complex of neurological symptoms that occurs just before or at the onset of migraine headache. Most patients with migraine have exclusively attacks without aura. Many patients who have frequent attacks with aura also have attacks without aura (code as 1.2 Migraine with aura and 1.1 Migraine without aura).
Premonitory symptoms occur hours to a day or two before a migraine attack (with or without aura). They include various combinations of fatigue, difficulty in concentrating, neck stiffness, sensitivity to light or sound, nausea, blurred vision, yawning and pallor. The terms prodrome and warning symptoms gare best avoided because they are often mistakenly used to include aura.
The majority of migraine auras are associated with headache fulfilling criteria for 1.1 Migraine without aura. For this reason the entity 1.2.1 Typical aura with migraine headache has been singled out below. Migraine aura is sometimes associated with a headache that does not fulfil criteria for migraine without aura and, in other cases, migraine aura may occur without headache. These two subforms are also now distinguished.
Aura with similar features has also been described in association with other well-defined headache types, including cluster headache; the relationships between aura and headache are not fully understood.
Before or simultaneously with the onset of aura symptoms, regional cerebral blood flow is decreased in cortex corresponding to the clinically affected area and often including an even wider area. Blood flow reduction usually starts posteriorly and spreads anteriorly and is usually above the ischaemic threshold. After one to several hours, gradual transition into hyperaemia occurs in the same region. Cortical spreading depression of Leão has been implicated.
Systematic studies have demonstrated that many patients with visual auras occasionally have symptoms in the extremities. Conversely patients with symptoms in the extremities virtually always also suffer visual aura symptoms. A distinction between migraine with visual aura and hemiparaesthetic migraine is probably artificial and therefore is not recognised in this classification. Patients with motor weakness are classified separately because of the dominantly inherited form, 1.2.4 Familial hemiplegic migraine, and because of clinical differences. The genetic relationship between migraine with aura and familial hemiplegic migraine has not been established.
The previously-defined syndromes migraine with prolonged aura and migraine with acute-onset aura have been abandoned. The great majority of patients with such attacks have other attacks that fulfil criteria for one of the subforms of 1.2 Migraine with aura and should be coded to that diagnosis. The rest should be coded to 1.6.2 Probable migraine with aura specifying the atypical feature (prolonged aura or acute-onset aura) in parenthesis.