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Teaching NeuroImages: A pediatric patient with headache and neck stiffness

A 14-year-old right-handed boy presented with sudden onset of severe headache and neck stiffness. Physical examination showed arm asymmetry with smaller size and muscle bulk (present since childhood) and increased deep tendon reflexes on the right, but normal strength. Brain CT and lumbar puncture ruled out subarachnoid hemorrhage or infection. MRI and angiography (figure) identified an unruptured type III spinal arteriovenous malformation at the C3-C4 level, supplied by the right vertebral artery.1 Subtle physical examination findings can indicate underlying pathology and should not be overlooked in the proper context. Vascular studies should be considered for severe headache with negative initial workup.2