A 12-year-old boy is rushed to the emergency room in a coma after falling from an upper story window of his home. MRI shows a subdural hematoma over the left hemisphere. What is the most likely source of intracranial bleeding in this patient?

Subdural hematoma reflects torn bridging veins in the subdural space. Unlike the epidural space, the subdural space can expand. Because bleeding in this situation is from veins, it usually stops spontaneously after an accumulation of 25 to 50 mL because of a local tamponade effect. However, this effect also can compress severed bridging veins and cause thrombosis. Because the brain is symmetric and a force applied in the sagittal plane similarly affects both cerebral hemispheres, it is not surprising that subdural hematomas are frequently bilateral. Tearing of the middle meningeal artery (choice D) causes epidural hemorrhage.Diagnosis: Subdural hematoma