Background/purpose Preoperative embolization of head, neck, and spinal tumors is frequently used to control tumor bleeding, reduce operative time, and achieve better resection. Numerous embolic materials have been used. The use of the liquid embolic agent Onyx is rapidly increasing but current experience is limited to small case series. Our purpose was to evaluate the indications, techniques, angiographic devascularization, blood loss, outcome, and general efficacy of preoperative tumor embolization with Onyx in a large series.

Methods Retrospective analysis of 100 consecutive cases of head, neck, and spinal tumors embolized with Onyx and prospective follow-up.

Results 100 patients (63 women, 37 men) were included. Tumors included 39 meningiomas, 23 metastases, 16 parangliomas, five juvenile nasal angiofibromas, five giant cell bone tumors, three Ewing's sarcomas, three hemangiomas, three hemangioblastomas, two multiple myelomas, and one osteoblastoma. In all patients, angiographic analysis of the feeding arteries and branches was performed and all embolizations were completed in a single session. Additional materials were used in 28 patients. No mortality or major complications were observed. Minor complications were seen in 11 patients. 85 patients underwent surgery; 79 within the next 48 h and six of them 4–188 days after embolization.

Conclusions Embolization of intracranial, head, neck, and spinal tumors with Onyx is effective and safe by a transarterial route or by direct puncture. Onyx penetrates well into the tumor capillary with less arterial catheterization. Studies are necessary to establish long term utility in adjunct or palliative tumor embolization.