Problem:
A 17-year-old boy is brought to the emergency department after he was hit on the head with a lead pipe, after which he was unconscious for several minutes. No seizure activity was witnessed. On arrival, he complains of a headache, particularly severe at the point where he was hit in the right frontoparietal region. On examination, he is found to have swelling and ecchymosis over this region. He is awake, alert, and fully oriented. A complete neurologic examination reveals no deficit. Plain radiographs of the skull show a linear, non-depressed skull fracture in the fronto-parietal skull that crosses the groove of the medial meningeal artery. During the following hour, he becomes sleepier and begins to vomit. A repeat neurologic examination at that time reveals him to be lethargic but without weakness, numbness, paresthesia or other focal deficit. What is the most likely cause of the neurologic deterioration? Select one: a. Diffuse axonal injury (DAI) b. Todd's phenomenon c. Subdural hematoma d. Epidural hematoma