Nationwide survey of the nature and risk factors of complications in embolization of meningiomas and other intracranial tumors: Japanese Registry of NeuroEndovascular Therapy 2 (JR-NET2)

Introduction: Embolization of intracranial tumor is widely performed in Japan, mainly before neurosurgical resection. A retrospective, multicenter, observational study in Japan was conducted to clarify the nature, frequency, and risk factors of complications in intracranial tumor embolization. Methods: Patients were derived from the Japanese Registry of NeuroEndovascular Therapy 2 (JR-NET2). A total of 20,854 patients were enrolled in JR-NET2, of which 1,018 patients (4.88 %) with intracranial tumors underwent embolization. The primary end point was the proportion of patients with a modified Rankin scale (mRS) score of 0-2 (independency) at 30 days. The secondary end point was the occurrence of complications related to the procedures. The risk factors of the occurrence of complications were studied. Results: The proportion of patients with mRS scores ≤2 at 30 days after procedure was 91.3 %. Complications occurred in 15 of the 1,012 patients (1.48 %). Multivariate analysis showed that embolization for tumors other than meningioma (OR, 4.626; 95 % CI, 1.347-14.59; p = 0.0105) was significantly associated with the development of complications. Conclusion: The frequency of complications after intracranial tumor embolization was relatively low in this large Japanese cohort. Embolization for tumors other than meningioma was the only significant risk factor for the occurrence of complications.