α[11C]methyl-L-tryptophan positron emission tomography in patients with alternating hemiplegia of childhood

Based on previous reports suggesting a role of the neurotransmitter serotonin in the pathomechanism of alternating hemiplegia of childhood and speculation that it may be a migraine variant, we measured brain serotonin synthesis in children with alternating hemiplegia of childhood. Clinical and neurodevelopmental data, as well as standard uptake values in 25 brain regions and whole-brain serotonin synthesis capacity (unidirectional uptake rate constant or K-complex), were assessed in six patients with alternating hemiplegia of childhood (three girls and three boys; mean age = 76/12 years) using α[ 11C]methyl-L-tryptophan positron emission tomography (PET). The PET studies were performed interictally in three patients, during the ictal state in two patients, and postictally in one patient. The PET data were compared to those obtained interictally from six age-matched patients with focal epilepsy (two girls and four boys; mean age = 78/12 years) and six non-age-matched apparently normal siblings of autistic ...