Delayed contralateral epidural hematoma after decompressive craniectomy for a traumatic acute subdural hematoma

After falling from a height, a 29-year-old male patient developed a traumatic left subdural hematoma (SDH) with brain swelling and a midline shift to the right side, as well as a small epidural hematoma (EDH) (thickness: <1 cm) overlying a contralateral temporal linear fracture. A decompressive craniectomy for SDH evacuation and the placement of an intracranial pressure (ICP) monitoring device were performed. Because of uncontrollable ICP (>35 mmHg) 48 hours after surgery, a left, extended decompressive craniectomy was performed in combination with therapeutic hypothermia for 6 days, including rewarming for 3 days. The patient remained stable for several days. However, the patient developed sudden right pupil dilatation with an uncal herniation on Day 14. Computed tomography revealed a considerable enlargement of the contralateral EDH. An emergency craniectomy was performed for EDH evacuation. In this paper, we describe this rare case, in which the delayed expansion of the contralateral EDH occurred 14 days after the initial surgery, and discuss its clinical management and radiologic findings, in addition to reviewing the literature and presenting the possible mechanism of this complication.