The field of interventional neuroradiology has experienced remarkable technological developments in microcatheters and embolic materials during the past two decades. The realm of meningioma therapy has benefited handsomely from the combination of these technical improvements and the knowledge of experienced practitioners in this field. Transarterial embolization has become a standard procedure in the preoperative management of meningiomas. The authors describe the indications, pretreatment evaluation, techniques, and outcomes when preoperative angiography and embolization are performed in the treatment of these tumors.
Christopher F. Dowd, Van V. Halbach and Randall T. Higashida
Grant B. Hieshima, Randall T. Higashida, Joseph Wapenski, Van V. Halbach and John R. Bentson
✓ A patient who presented with multiple episodes of subarachnoid hemorrhage was diagnosed as having a large mid-basilar artery aneurysm that had no definable surgical neck. Balloon embolization was performed utilizing two detachable silicone balloons to occlude the mid-basilar artery and the aneurysm. The procedure was carried out with the patient fully awake and alert. One day after the procedure, the patient developed pontine and cerebellar ischemia which completely resolved after 5 days on heparin therapy. A follow-up angiogram performed immediately after the procedure and at 3 months demonstrated complete occlusion of the mid-basilar artery and the aneurysm. The patient was intact neurologically upon discharge 5 days after the embolization procedure and has since resumed his normal activities. Balloon embolization therapy may offer some advantages over surgical methods for the treatment of such therapeutically challenging aneurysms.
Leslie D. Cahan, Randall T. Higashida, Van V. Halbach and Grant B. Hieshima
✓ In recent years, it has become evident that the most common form of arteriovenous malformation to involve the spinal cord in adults is a low-flow fistula with its nidus located on the dura in relation to the dorsal nerve root. This lesion, termed “radiculomeningeal fistula” (RMF), is drained by the intradural coronal venous system and most likely causes neurological deficits due to raised venous pressure within the spinal cord. The therapy that was formerly recommended was multilevel laminectomy with microsurgical stripping of the intradural vessels. However, that procedure focused on the draining veins rather than the nidus, and it has been replaced by direct treatment of the nidus or by disconnecting the nidus from the coronal venous system. This paper reports variants of RMF's that show a wider spectrum of the clinical and radiological findings than has been previously reported. Three patients presenting with extradural venous drainage, intraspinal hemorrhage, and/or sudden non-hemorrhagic neurological decline are reported. A more complete understanding of RMF facilitates the radiological and clinical evaluation of these patients and enables the surgeon to modify the therapy in a significant way.
Grant B. Hieshima, Randall T. Higashida, Joseph Wapenski, Van V. Halbach, Leslie Cahan and John R. Bentson
✓ Interventional neurovascular techniques have advanced to a level where treatment of intracranial aneurysms by intravascular detachable balloon embolization therapy is now possible. A patient is presented who had a spontaneous subarachnoid hemorrhage from a large aneurysm of the distal basilar artery. The aneurysm arose at the bifurcation of the posterior cerebral arteries and measured 15 × 9 × 9 mm. With the patient fully awake, a detachable silicone balloon was passed into the basilar artery by a transfemoral arterial approach. Stenosis (> 60%) of the mid-section of the basilar artery, secondary to arterial vasospasm from the recent hemorrhage, was present. The stenosis was treated by transluminal angioplasty, after which the balloon was passed into the aneurysm and detached. A follow-up angiogram 3 months later demonstrated complete occlusion of the aneurysm and a widely patent basilar artery at the angioplasty site.
Randall T. Higashida, Van V. Halbach, Leslie D. Cahan, Grant B. Hieshima and Yoshifumi Konishi
✓ Treatment of complex and surgically difficult intracranial aneurysms of the posterior circulation is now being performed with intravascular detachable balloon embolization techniques. The procedure is carried out under local anesthesia from a transfemoral arterial approach, which allows continuous neurological monitoring. Under fluoroscopic guidance, the balloon is propelled by blood flow through the intracranial circulation and, in most cases, can be guided directly into the aneurysm, thus preserving the parent vessel. If an aneurysm neck is not present, test occlusion of the parent vessel is performed and, if tolerated, the balloon is detached.
Twenty-six aneurysms in 25 patients have been treated by this technique. The aneurysms have involved the distal vertebral artery (five cases), the mid-basilar artery (six cases), the distal basilar artery (11 cases), and the posterior cerebral artery (four cases). The aneurysms varied in size and included three small (< 12 mm), 15 large (12 to 25 mm), and eight giant (> 25 mm). Fifteen patients (60%) presented with hemorrhage and 10 patients (40%) with mass effect. In 17 cases (65%) direct balloon embolization of the aneurysm was achieved with preservation of the parent artery. In nine cases (35%), because of aneurysm location and size, occlusion of the parent vessel was performed. Complications from therapy included three cases of transient cerebral ischemia which resolved, three cases of stroke, and five deaths due to immediate or delayed aneurysm rupture. The follow-up period has ranged from 2 months to 43 months (mean 22.5 months).
In cases where posterior circulation aneurysms have been difficult to treat by conventional neurosurgical techniques, intravascular detachable balloon embolization may offer an alternative therapeutic option.
Results of combined endovascular and neurosurgical treatment in 16 patients
Stanley L. Barnwell, Van V. Halbach, Randall T. Higashida, Grant Hieshima and Charles B. Wilson
✓ Of the 88 patients evaluated for symptomatic dural arteriovenous (AV) fistula over the past 8 years, 16 had large or complicated lesions that could not be treated with standard transvascular approaches or in which such treatment had been unsuccessful. Eleven fistulas were located in the transverse sinus, two in the cavernous sinus, two in the straight sinus, and one in the falx-tentorial region near the vein of Galen. The patients were treated with a combination of endovascular and neurosurgical techniques. Fourteen patients underwent preoperative transarterial embolization; this procedure closed the fistula in one patient. In the remaining 15 patients, surgery was performed to provide access to the fistula for embolization from either the venous or the arterial side, or for excision of the fistula. Transvenous embolization completely obliterated the fistula in seven of nine patients; the fistulas were embolized incompletely through the feeding arteries in two patients; and complete surgical resection of the lesion was accomplished in four patients. Complications related to venous occlusion occurred in two patients and one patient suffered communicating hydrocephalus that was effectively treated by shunting. There were no deaths. The results suggest that combined endovascular and neurosurgical techniques are a safe and effective means for the treatment of selected complex dural AV fistulas.
Intravascular stent and endovascular coil placement for a ruptured fusiform aneurysm of the basilar artery
Case report and review of the literature
Randall T. Higashida, Wade Smith, Daryl Gress, Ross Urwin, Christopher F. Dowd, Peter A. Balousek and Van V. Halbach
✓ The authors demonstrate the technical feasibility of using intravascular stents in conjunction with electrolytically detachable coils (Guglielmi detachable coils [GDCs]) for treatment of fusiform, broad-based, acutely ruptured intracranial aneurysms and review the literature on endovascular approaches to ruptured aneurysms and cerebral stent placement. A 77-year-old man presented with an acute subarachnoid hemorrhage of the posterior fossa. A fusiform aneurysm with a broad-based neck measuring 12 mm and involving the distal vertebral artery (VA) and proximal third of the basilar artery (BA) was demonstrated on cerebral angiography. The aneurysm was judged to be inoperable. Six days later a repeated hemorrhage occurred. A 15-mm-long intravascular stent was placed across the base of the aneurysm in the BA and expanded to 4 mm to act as a bridging scaffold to create a neck. A microcatheter was then guided through the interstices of the stent into the body and dome of the aneurysm, and GDCs were deposited for occlusion.
The arteriogram obtained after stent placement demonstrated occlusion of the main dome and body of the aneurysm. The coils were stably positioned and held in place by the stent across the distal VA and BA fusiform aneurysm. Excellent blood flow to the distal BA and posterior cerebral artery was maintained through the stent. There were no new brainstem ischemic events attributable to the procedure. No rebleeding from the aneurysm had occurred by the 10.5-month follow-up evaluation, and the patient has experienced significant neurological improvement.
Certain types of intracranial fusiform aneurysms may now be treated by combining intravascular stent and GDC placement for aneurysm occlusion via an endovascular approach. This is the first known clinical application of this novel approach in a ruptured cerebral aneurysm.