Neurologic complications after particle embolization of intracranial meningiomas

Abstract

Background and purpose: Preoperative embolization of meningiomas is frequently used to facilitate surgery and to reduce intraoperative blood loss. The purpose of this study was to evaluate the frequency of procedure-related neurologic complications during and after particle embolization of intracranial meningiomas.

Methods: Between 1996 and 2004, 185 consecutive patients underwent particle embolization of an intracranial meningioma. Devascularization was performed by means of superselective probing of the tumor-feeding vessels and ensuing free-flow embolization with spherical particles. All procedures were performed with systemic heparinization.

Results: Six patients (3.2%) had ischemic events with neurologic deficit. Two had amaurosis, and four patients presented with hemiparesis. Hemorrhage occurred in six patients (3.2%). In five of these patients, rapid microsurgical tumor removal resulted in a favorable outcome without persistent neurologic deficit. In one patient, massive intratumoral, subarachnoid, and subdural hemorrhage was lethal.

Conclusion: Particle embolization of meningiomas is associated with a substantial risk of ischemic and hemorrhagic events. The individual risk-to-benefit ratio of embolization should be thoroughly considered.

Fig 1.

Patient 2. Peritumoral ischemia after embolization (Embospheres, 40–120 μm) of a recurrent frontal meningioma. A, Predominant blood supply by the ipsilateral middle meningeal artery was embolized with spherical particles. B, After the procedure, the patient had left-sided hemiparesis. CT shows attenuating pooling of contrast medium in the tumor. C, Next day, T1-weighted spin-echo MR image shows no contrast enhancement, indicating complete devascularization of the tumor. D, DC map shows a small, hypointense rim of brain parenchyma around the meningioma, indicating cytotoxic edema (arrows). This was interpreted as particles passing into the surrounding brain tissue via leptomeningeal collaterals.

Fig 2.

Patient 11. Subarachnoid and intratumoral hemorrhage during embolization (Embospheres, 100–300 μm) of a right frontal-convexity meningioma. A and B, Images show blood supply by the ipsilateral middle meningeal artery (A), which was subsequently devascularized with particles, and leptomeningeal branches of the middle cerebral artery (B). C and D, At the end of the procedure, patient had sudden-onset headache. Angiograms show subarachnoid extravasation of contrast medium (arrows in C). Control run in the internal carotid artery (D) shows disappearance of the leptomeningeal supply, indicating complete tumor devascularization. E, Postprocedural CT shows intratumoral and subarachnoid hemorrhage. At surgery, bleeding from intratumoral vessels were slight; the fresh intratumoral clot and tumor were easily removed. The patient recovered completely.

Fig 3.

Patient 12. An 81-year-old woman with fatal subdural, subarachnoid, and intratumoral hemorrhages after embolization (Bead Block,100–300 μm). A and B, Embolization of a large, right temporal meningioma with a predominant middle meningeal arterial supply. C, Ipsilateral middle meningeal artery was superselectively probed and embolized with spherical particles. D, Procedure was abandoned after the application of one vial because the patient had back pain. Control image reveals marked tumoral devascularization. E and F, Afterward, the patient had no new neurologic symptoms, but 2 hours later, she was comatose with fixed, dilated pupils. CT shows extensive subdural (solid arrows), subarachnoid (dotted arrow) and intratumoral hemorrhage. Because of her age and clinical state, she did not undergo surgery and died the next day.

Fig 4.

Representative histologic findings after periprocedural hemorrhage. A, Patient 8. Section shows massive iron deposition (blue) indicating previous intratumoral hemorrhage (solid arrows) around acute hemorrhage (brown, dotted arrows) (hematoxylin-eosin and Prussian blue, original magnification ×8). B and C, Patient 11. Pathologic vessels with variable wall thickness were seen in four of five patients (B, hematoxylin-eosin, original magnification ×20). In some areas, the wall is atypically thin relative to the lumen (arrows in B). These vessels were positive for actin, indicating arteries (C, original magnification ×50). Similar vessels, also filled with particles, were seen in other patients with hemorrhage.