Onyx embolization for the endovascular treatment of infectious and traumatic aneurysms involving the cranial and cerebral vasculature.

Background: Onyx is a liquid non-adhesive viscous embolic agent ideal for slow targeted injections which is currently approved for the treatment of intracranial aneurysms and arteriovenous malformations.

Methods: We performed a single-center retrospective analysis of consecutive patients who underwent off-label use of Onyx as the single embolic agent for the treatment of traumatic or infectious pseudoaneurysms involving the cerebral or cranial vasculature.

Results: A total of nine pseudoaneurysms treated by Onyx embolization were identified.

Embolization of intra-axial hypervascular tumors with Onyx: report of three cases.

Complete surgical resection of intra-axial hypervascular tumors located in the posterior fossa, in particular hemangioblastomas, may be challenging due to tumor location, mass effect and excessive bleeding. Embolization of these lesions can be done preoperatively or as a palliative measure in patients who are not surgical candidates. Preoperative embolization may reduce intraoperative blood loss, shorten surgical time and increase the chance of a complete resection.

Predictors of functional outcome vary by the hemisphere of involvement in major ischemic stroke treated with intra-arterial therapy: a retrospective cohort study.

Background: Conflicting data exists regarding the effect of hemispheric lateralization on acute ischemic stroke outcome. Some of this variability may be related to heterogeneous study populations, particularly with respect to the level of arterial occlusion. Furthermore, little is known about the relationship between stroke lateralization and predictors of outcome.

Onyx embolization for the treatment of spinal dural arteriovenous fistulae: initial experience with long-term follow-up. Technical case report.

Objective: Spinal dural arteriovenous fistulae (SDAVF) are the most common variety of spinal vascular malformations. The Onyx liquid embolic system (ev3 Neurovascular, Irvine, CA) was recently approved for the treatment of intracranial arteriovenous malformations, but its use to treat SDAVFs is not yet well established. We report our initial experience with Onyx embolization in the treatment of SDAVFs.

Reversible parkinsonism after treatment of dural arteriovenous fistula.

Background And Purpose: The most common causes of parkinsonism are degenerative and irreversible. Structural causes of reversible parkinsonism are exceptionally rare, but have been reported in association with deep cerebral venous thrombosis and dural arteriovenous fistula (DAVF). We now report a case of parkinsonian syndrome reversed by treatment of a dural arteriovenous malformation.

Low-pressure balloon angioplasty with adjuvant pharmacological therapy in patients with acute ischemic stroke caused by intracranial arterial occlusions.

Introduction: The use of coronary balloons in the cerebral vasculature is limited due to their poor trackability and increased risk of vessel injury. We report our experience using more compliant elastomer balloons for thrombus resistant to intraarterial (IA) pharmacological and mechanical thrombolysis in acute stroke.

Methods: We retrospectively analyzed 12 consecutive patients with an occluded intracranial artery treated with angioplasty using a low-pressure elastomer balloon.

High-dose bosentan in the prevention and treatment of subarachnoid hemorrhage-induced cerebral vasospasm: an open-label feasibility study.

Objective: To evaluate the safety of high-dosages of the endothelin ET(A/B )receptor antagonist bosentan in SAH patients at high-vasospasm risk.

Methods: Ten Fisher group-3 SAH patients, enrolled within 96 h of ictus, received bosentan in a dose-escalation manner (20, 30, 40 mg/kg/day orally every 4 hours on treatment days 1, 2, and 3 respectively, to a maximum dose of 4000 mg/day), followed by maintenance of the maximum tolerated dose until 14 days post-SAH or vasospasm resolution. Further management followed standard protocols: nimodipine in all patients; daily transcranial Doppler (TCD); "triple-H"/endovascular treatment, as indicated.

MRI of spontaneous fluctuations after acute cerebral ischemia in nonhuman primates.

Purpose: To study the spontaneous low-frequency blood oxygenation level-dependent (BOLD) functional MRI (fMRI) signal fluctuations during hyperacute focal cerebral ischemia.

Materials And Methods: A stroke model in nonhuman primates (macaques) was used in this study. Spontaneous fluctuations were recorded using a series of gradient-recalled echo (GRE) echo-planar imaging (EPI) images.

Comparison of ruptured vs unruptured aneurysms in recanalization after coil embolization.

Background: Aneurysm recanalization is a significant problem in coil-treated intracranial aneurysms. We hypothesize ruptured aneurysms are more likely to demonstrate this phenomenon than unruptured aneurysms.

Methods: This was a retrospective study over 4 years.

Serial diffusion tensor MRI after transient and permanent cerebral ischemia in nonhuman primates.

Background And Purpose: We measured the temporal evolution of the T2 and diffusion tensor imaging parameters after transient and permanent cerebral middle cerebral artery occlusion (MCAo) in macaques, and compared it to standard histological analysis at the study end point.

Methods: Stroke was created in adult male macaques by occluding a middle cerebral artery branch for 3 hours (transient MCAo, n=4 or permanent occlusion, n=3). Conventional MRI and diffusion tensor imaging scans were performed 0 (acute day), 1, 3, 7, 10, 17, and 30 days after MCAo.

A nonlinear mesh-warping technique for correcting brain deformation after stroke.

This article presents a warping technique for correcting brain tissue distortion on magnetic resonance imaging (MRI) scans due to stroke lesion growth and for mapping MRI scans to histological sections. Meshes are imposed upon the images for feature specification, and these features are exactly matched in the different images to be mapped, while the other voxels are matched by interpolation. This technique was tested on serial MR images and histological sections that were acquired in a nonhuman primate model of stroke.

Vertebral augmentation complicated by perioperative addisonian crisis.

Background: We describe a case of perioperative Addisonian crisis induced by vertebral augmentation. While several complications of vertebral augmentation have been reported previously, related to the technical procedure, to our knowledge, perioperative Addisonian crisis from vertebral augmentation has not been reported in the literature.

Objective: To report an Addisonian crisis perioperative to vertebral augmentation.

Balloon kyphoplasty for vertebral compression fracture using a unilateral balloon tamp via a uni-pedicular approach: technical note.

Objective: Percutaneous balloon kyphoplasty, like percutaneous vertebroplasty is a therapeutic intervention for painful osteoporotic vertebral body compression fracture. The procedure involves placement of bilateral inflatable balloon tamps in the fractured vertebral body via a bilateral transpedicular or bilateral extra-pedicular approach. We describe performance of balloon kyphoplasty using a unilateral, single, balloon tamp via a unilateral transpedicular approach.

Kyphoplasty for vertebral compression fracture via a uni-pedicular approach.

Background: Percutaneous kyphoplasty using a bone expander polymer device, such as percutaneous vertebroplasty and balloon kyphoplasty, is a therapeutic intervention for painful osteoporotic vertebral body compression fractures. Typically the procedure involves placement of bilateral Sky Bone Expanders in the fractured vertebral body via a transpedicular approach. We describe performance of "SKy"phoplasty using the Disc-O-Tech Sky Bone Expander (Disc-O-Tech Medical Technologies, Herzliya, Israel, and Monroe Township, New Jersey) via a unilateral transpedicular approach.

Complications of cerebral arteriovenous malformation embolization: multivariate analysis of predictive factors.

Objective: Embolization is an important therapeutic modality in the multidisciplinary management of arteriovenous malformations (AVM); however, prior series have reported a wide variability in overall complication rates caused by embolization (10-50% neurological deficit, 1-4% mortality). In this study, we reviewed our experience with AVM embolization and analyzed factors that might predict complications and clinical outcomes after AVM embolization.

Methods: We analyzed our combined neurovascular unit's results with AVM embolization from 1993 to 2004 for the following outcomes measures: 1) clinically significant complications, 2) technical complications without clinical sequelae, 3) discharge Glasgow Outcome Scale score, and 4) death.

Middle cerebral artery occlusion in Macaca fascicularis: acute and chronic stroke evolution.

Background: An intravascular stroke model designed for magnetic resonance imaging was developed in Macaca fascicularis (M. fascicularis) to characterize serial stroke lesion evolution. This model produces a range of stroke lesion sizes which closely mimics human stroke evolution.

Safety of heparinization for cerebral aneurysm coiling soon after external ventriculostomy drain placement.

Objective: Our practice has been to heparinize patients for cerebral aneurysm coiling even after recent external ventriculostomy drain (EVD) placement. The current medical literature cites a 12.5% symptomatic hemorrhage rate with heparinization after recent EVD placement.

Dynamic susceptibility contrast perfusion imaging of cerebral ischemia in nonhuman primates: comparison of Gd-DTPA and NMS60.

Purpose: To study a new gadolinium (Gd) contrast agent-NMS60-for MR perfusion-weighted imaging (PWI) of brain tissue.

Materials And Methods: NMS60 is a Gd3+ trimer with a molecular weight of 2158 Daltons, and a T2 relaxivity almost three times higher than that of Gd-DTPA. Middle cerebral artery (MCA) occlusion was induced in nine nonhuman primates.

Heparin-induced thrombocytopenia Type II in subarachnoid hemorrhage patients: incidence and complications.

Objective: Heparin-induced thrombocytopenia Type II (HIT II) is the autoimmune-mediated severe form of the disease characterized by a significant reduction in platelets, and it carries a high risk of "paradoxical" serious thrombotic complications. Although HIT II has been studied in several different patient populations, the incidence of HIT II and the rate of thrombotic complications have never been reported in a neurosurgical patient population. Subarachnoid hemorrhage (SAH) patients, among neurosurgical patient populations, have a high exposure to heparin because they are in critical care units and have indwelling vascular catheters.

Effect of clipping, craniotomy, or intravascular coiling on cerebral vasospasm and patient outcome after aneurysmal subarachnoid hemorrhage.

Objective: Although several recent studies have suggested that the incidence of vasospasm after aneurysmal subarachnoid hemorrhage is lower in patients undergoing aneurysmal coiling as compared with clipping, other studies have had conflicting results. We reviewed our experience over 8 years and assessed whether clipping, craniotomy, or coiling affects patient outcomes or the risk for vasospasm.

Methods: We included 515 patients with aneurysmal subarachnoid hemorrhage, identified prospectively from November 2000 to February 2003 (243 patients) and retrospectively from November 1995 to October 2000 (272 patients), by using International Classification of Diseases, 9th Revision, codes for subarachnoid hemorrhage.

Persistent nonfused segments of the basilar artery: longitudinal versus axial nonfusion.

Embryologic development of the basilar artery occurs along two axis systems: longitudinal fusion and axial fusion. Longitudinal fusion consists of midline fusion of paired ventral arteries and reflects the simplified pattern of arterial anatomy found in the spinal cord. Axial fusion consists of fusion of the distal basilar artery, which arises from the caudal division of the internal carotid artery, to the midbasilar agenesis to the posterior inferior cerebellar artery termination of the vertebral arteries.

Results of a prospective protocol of computed tomographic angiography in place of catheter angiography as the only diagnostic and pretreatment planning study for cerebral aneurysms by a combined neurovascular team.

Objective: At many centers, patients undergo both computed tomographic angiography (CTA) and digital subtraction angiography (DSA). This practice negates most of the advantages of CTA, and it renders the risks and disadvantages of the two techniques additive. Previous reports in the literature have assessed the sensitivity and specificity of CTA compared with DSA; however, these investigations have not analyzed the clinical implications of a protocol that replaces DSA with CTA as the only diagnostic and pretreatment planning study for patients with cerebral aneurysms.

Preliminary experience with intra-arterial nicardipine as a treatment for cerebral vasospasm.

Background And Purpose: Papaverine is the primary intra-arterial (IA) treatment for vasospasm after aneurysmal subarachnoid hemorrhage (SAH); however, is it limited in effect and by adverse effects. We prospectively studied the use of IA nicardipine as a treatment for vasospasm.

Methods: Over 12 months, all patients with SAH who required interventional treatment for vasospasm were given IA nicardipine with or without angioplasty.

Age-dependent differences in short-term outcome after surgical or endovascular treatment of unruptured intracranial aneurysms in the United States, 1996-2000.

Introduction: Unruptured intracranial aneurysm patients are frequently eligible for both open surgery ("clipping") and endovascular repair ("coiling"). We compared short-term end points (mortality, discharge disposition, complications, length of stay, and charges) for clipping and coiling in a nationally representative discharge database.

Methods: We conducted a retrospective cohort study using Nationwide Inpatient Sample data from 1996 to 2000.