A 20 yo M presents to the ED following a high speed motor vehicle collision where he was a restrained driver. Per EMS, there was reported LOC. On ED arrival, he is awake with a GCS of 15 and without focal neurologic deficit. Exam reveals abrasions to the R parietal scalp. A CT is obtained. What's the diagnosis? (scroll down for answer) 

Answer: Epidural hematoma, with right to left midline shift

• Classic initial presentation: head trauma w/ LOC, followed by lucid interval
• Middle meningeal artery is most common source of bleeding, location of bleeding usually temporal
• Often associated with skull fracture
• Rapidly progressive neurologic deterioration follows lucid interval
• Biconvex (football shaped) space occupying lesion on CT, limited by cranial suture lines
• Time to evacuation is most important factor for outcome
• Can cause rapid herniation

References:

Hasse et al. “Traumatic Brain Injury.” Critical Care Emergency Medicine, 2e. Farcy et al eds. New York, NY: McGraw-Hill, 2017.

Ma et al. “Head Trauma.” Tintinalli’s Emergency Medicine Manual, 8e. Cydulka et al eds. New York, NY: McGraw-Hill, 2018.