Yоu аre perfоrming а fоllow up on а 3 yo male who was seen in the ED for a first time seizure. His labs in the ED were normal. There was no neuroimaging done. His exam in the office is nonfocal and he has not had another seizure since his ED discharge. Because you are unable to determine the etiology for the seizure, the next step for his work up that you will need to order is: