Persistent Migraine Aura: New Cases, a Literature Review, and Ideas About Pathophysiology.

Background Persistent migraine aura without infarction ( PMA) is a rare condition that is defined as an aura that lasts longer than 1 week in absence of infarction. Two types of PMA have been distinguished, notably persistent primary visual disturbance ( PPVD) and typical aura ( TA). Objectives This case-based review article describes four new cases of PMA as well as reviews all cases reported, trying to identify relevant associations, in particular with respect to functional investigations. Methods We performed a systematic literature search, extending from the period when it was first described (1991) to March 2014. We included all case descriptions of which criteria for PMA formulated in the International Classification of Headache Disorders, second edition, were met. In addition, we described four new cases. Results We identified 47 cases of PMA, 27 PMA-PPVD and 19 PMA-TA. In one case, there was not enough information to define the type of PMA. The mean age of onset was 30 years, varying from 7 to 74 years. The duration of symptoms varied from 9 days to 28 years. Besides a longer duration in symptoms in the PMA-PPVD group, we could not identify any differences between these groups. Some authors report occipital hypoactivity on Tc99m-hexamethylpropylene amine oxime -single-photon emission computed tomography ( Tc99m- HMPAO-SPECT) or fluorodeoxyglucose-positron emission tomography ( FDG-PET) in PMA cases, but data are inconsistent. Multiple drugs have been used for the treatment of PMA, usually with little effect. Lamotrigine seems to be the most effective drug. Conclusion Despite the fact that 47 cases of PMA have been reviewed in this paper, many questions remain. The cases that have been described so far show inconsistent data with respect to the results of functional studies as well as treatment effects. The pathophysiology of PMA is still largely a matter of conjecture. [ABSTRACT FROM AUTHOR]