Delayed presentation of traumatic cerebral and dural arteriovenous fistulae after a BB gun accident in a pediatric patient: Case report

BACKGROUND AND IMPORTANCE:: To present a case of traumatic cortical and dural arteriovenous fistula (AVF) after a BB gun accident. CLINICAL PRESENTATION:: The patient presented with a small left frontal subdural hematoma and small contusions in the left frontal lobe after he was shot with a BB. He had no skull fractures or significant midline shift. The patient, who was neurologically intact, was discharged after 3 days of observation and having undergone serial computed tomography imaging. Five days later, the patient developed lethargy and emesis. Computed tomography showed a 5 × 3 × 5 cm intraparenchymal hematoma in the left frontal lobe. Emergency evacuation of the hematoma revealed a cortical AVF, which was resected. Postoperative angiography showed a dural AVF of the left middle meningeal artery, draining into the superior ophthalmic vein and a dural vein. The dural AVF was embolized with n-butyl cyanoacrylate. The patient was discharged after 3 days with no deficits. Conclusion: The subdural hematoma and contusions were caused by a BB, which often are used in low-velocity and small caliber weapons. Not all BB guns are low velocity, and the consequences can be dramatic. The BB gun used here was pneumatic. The patient had no skull fractures. Several days of stable imaging and normal examinations suggested nothing sinister. His initial bleeds appeared disproportionate to the mechanism. The delayed presentation of the debilitating hematoma in this case stresses the need for vigilance on the part of practitioners and families when patients have a suspicious bleed.