RESUMO
BACKGROUND: Aneurysmal bone cysts (ABCs) comprise 1%-2% of all bone tumors. ABCs involving the upper cervical spine in pediatric patients complicate intervention because of an immature skeleton and nearby neurovascular elements. Treatment often consists of surgical intervention with preoperative embolization to mitigate blood loss. During selective arterial embolization, it is important to be aware of extracranial-intracranial anastomoses from tumor feeding vessels. We describe a C2 vertebrae ABC that had multiple tumor arteries anastomosing with bilateral vertebral arteries. CASE DESCRIPTION: A 3-year-old healthy girl presented with 1 month of progressive neck pain and palpable posterior neck mass. Imaging was most consistent with an ABC of the C2 vertebra. Preoperative embolization was planned. Angiography demonstrated tumor arterial supply anastomosing with the left and right vertebral artery stemming from the ascending and deep cervical artery branches. Tumor embolization was therefore carried out using coils and larger embolization particles to decrease ischemic stroke risk. Follow-up angiography showed successful tumor embolization with no vertebrobasilar complications. Surgical excision was uncomplicated and the patient's cervical spine has remained stable without fusion. CONCLUSIONS: Preoperative embolization for ABC resection is common, but thorough angiography must be done to rule out dangerous extracranial-intracranial anastomoses. This case demonstrated 2 key anastomoses with the vertebral artery that if not recognized, could lead to disastrous consequences. Comprehensive angiographic evaluation is necessary because previous reports have described ischemic complications from embolization because of unrecognized vertebrobasilar anastomoses. If any angiographic evidence is seen, then larger particle size, coil embolization, or abandoning the case should be considered.