A 30-year-old woman presented with a history of generalized tonic-clonic seizures since childhood, occurring for the first time at age 9. The initial diagnostic workup at age 13 demonstrated a distinctive calcified mass of the left frontal lobe on CT (figure, A). Together with a single facial nevus, the lesion was suspected to represent Sturge-Weber-like phakomatosis; however, the patient's clinical history and physical examination failed to reveal further evidence of a neurocutaneous syndrome. Neither MRI nor biopsy for histologic confirmation of the diagnosis was performed. At age 18 the patient was lost to follow-up at the children's hospital.