Introduction: Deep-seated Arteriovenous Malformations (AVM) are commonly dealt with embolization and subsequent Radiosurgery on the residual nidus. Complications of Surgery in AVMs are well known but complications of endovascular treatment have been less frequently reported.

Methods: 55-year-old female was treated by embolization for a large deep-seated front-insular AVM fed by the left pericallosal artery and the M1 segment of the left Middle Cerebral Artery. Endovascular treatment consisted of Microplex coils embolization during one session in July 2010. A residual nidus was treated with Gamma knife in March 2011. Six months later, the patient deteriorated suddenly.

Results: MR imaging showed strong ring-enhancement surrounding the treated AVM with severe brain edema. We performed a left decompressive craniectomy as the patient developed temporal herniation with sudden coma. Intracerebral bacteriological sampling revealed Propioni bacterium. The patient received antibiotics for 6 weeks and recovered completely. Endovascular treatment may be associated with serious complications although it seems less invasive than surgery. Meyer et al. reported a bacteremia occurrence rate of 32% after endovascular procedures lasting more than 2 hours. In our case, the causative organism was a skin commensal germ.

Conclusions: Brain abscess may rarely complicate AVM embolization. The diagnosis must be evoked in front of neurological impairment following embolization, with ring enhancement on imaging. Antibiotic prophylaxis must be considered in endovascular procedures to prevent infectious complications. In case of associated Radiosurgery, abscess must be differentiated from radionecrosis.

Patient Care: Prevention of infectious complications in endovascular therapy. Improvement in treatment of complicated cerebral abscess.

Learning Objectives: Describe unusual complication of endovascular treatment of AVMs. Discuss the need for Prophylactic antibiotherapy in endovascular procedures. Discuss the place of decompressive craniotomy in patients with cerebral abscess and severe brain edema.

References: Meyer P, Reizine D, Aymard A, et al. Septic complications in interventional radiography: evaluation of risk and preventive measures: preliminary studies. J Intervent Radiol 1988;3:73–75