Rare clinical findings in a patient with sporadic hemiplegic migraine: FDG-PET provides diminished brain metabolism at 10-year follow-up.

BACKGROUND

Sporadic hemiplegic migraine (SHM) is defined as migraine attacks associated with some degree of motor weakness during the aura phase and where no first-degree relative has identical attacks. SHM has a wide inter- and intraindividual clinical spectrum and, in case of prolonged aura symptoms and disturbed consciousness, can mimic several other acute neurological diseases.

METHODS

In 1996, during his wedding night, a 28-year-old man developed left face, arm and leg weakness, nausea and a throbbing headache. Neurological examination on presentation revealed stupor, fever, meningism and left hemiplegia. There were no abnormalities on emergency magnetic resonance. Lumbar puncture showed mild lymphocytic pleocytosis and slightly elevated protein. He received symptomatic treatment. Subsequent genetic analysis revealed the T666M mutation in the CACNA1A gene of chromosome 19. He was diagnosed with SHM. In 2005, at the end of another episode of hemiplegic migraine (HM), he for the first time developed an episode of paranoid psychosis with anxiety and visual hallucinations. The psychiatric symptoms resolved within a week.

CONCLUSIONS

All perfusion SPECT and transcranial Doppler studies performed in the first days of HM attacks were consistent with hyperemia of the hemisphere contralateral to the neurological signs. FDG-PET/CT in January 2013 revealed a diffusely reduced glucose metabolism of the supratentorial cortex and marked asymmetric hypometabolism of the left cerebellum. The finding of progressive cortical metabolic dysfunction over years appears as a new finding. Glucose hypometabolism may indicate primary neuronal dysfunction as the cause of the prolonged deficits.