Images from Headache Epidermal Hematoma Sans “Lucid Interval” is marked by the so-called “lucid interval,” no more than one-half of such cases exhibit normal or nearnormal neurologic function during the period that lies between initial concussive injury and initiation of the herniation process induced by the accumulating hematoma. Especially when the hemorrhage is located posteriorly and results from rupture of a venous sinus rather than the middle meningeal artery or one of its branches, the distinctive lucid interval may be lacking. Regardless, the take-home message is that neurologic deterioration following a significant closed head injury calls for further and immediate diagnostic evaluation. A 9-year-old boy fell from his bike and struck his head on a concrete curb. Although he was able to respond to parents and friends, he remained sleepy and confused over the ensuing hour. In the emergency room, he was stuporous but arousable and exhibited no lateralizing signs. Noncontrasted brain CT was performed and demonstrated a large biconvex epidural hematoma with associated mass effect (Figure). The clot was evacuated, and 1 week later he was neurologically normal. Editor’s note: Although we teach our students that the clinical course of an epidural hematoma classically 79
