Decreased hemispheric water mobility in hemiplegic migraine related to mutation of CACNA1A gene

We report a reversible reduction of water diffusion in the brain during a p rolonged attack of hemiplegic migraine. The patient had a sporadic mutation of the CACNA1A gene. The diffusion changes were observed in the contralate ral hemisphere 3 and 5 weeks after the onset of hemiplegia. These results s uggest the occurrence of hemispheric cytotoxic edema during severe attacks of hemiplegic aura. The mechanisms underlying such ultrastructural modifica tions are unknown but an abnormal release of excitatory amino acids can be hypothesized.