The penumbra coil 400 system for treatment of wide-necked intracranial aneurysms: initial single-center experience.

Endovascular treatment of wide-necked intracranial aneurysms frequently requires stent- or balloon-assisted coiling to prevent coil herniation into the parent artery. Provided that coils can be securely deployed within the aneurysm sac, these adjunctive devices and their associated risk can be avoided. The Penumbra 400 Coil (PC-400) has a larger diameter than conventional coils and is constructed completely of metal, a feature that increases the coil stability and may improve its ability to respect the aneurysm neck. The purpose of this study was to examine the frequency of adjunctive stent usage when coiling wide-necked intracranial aneurysms with the PC-400 in comparison with conventional coils. We examined consecutive patients with unruptured wide-necked aneurysms treated at our institution with endovascular coils. Aneurysm characteristics and procedural outcomes were compared between patients treated with PC-400 compared with a control group treated with conventional coils. Thirty-eight patients met criteria for this study. Stent-assisted coiling was required in 34 % fewer cases using PC-400 compared with conventional coils (P = .049). Fewer coils and less length were required with the PC-400 to obtain the same packing densities, occlusion types, and short-term stability. This may reduce treatment cost and prove to be valuable in patients with contraindications to dual antiplatelet therapy.

Mild exercise reduces cerebral vasospasm after aneurysm subarachnoid hemorrhage: a retrospective clinical study and correlation with laboratory investigation.

BACKGROUND: Aneurysmal subarachnoid hemorrhage (SAH) is a leading cause of death and disability and is often complicated by cerebral vasospasm (CV). Conventional management to prevent CV includes bedrest; however, inactivity places the patient at risk for nonneurological complications. We investigated the effect of mild exercise after SAH in clinical and laboratory settings. METHODS: Clinical: Data from 80 patients with SAH were analyzed retrospectively. After aneurysms were secured, physical therapy was initiated as tolerated. CV and complications were compared by the timing of active physical therapy. Laboratory: 18 Rodents were divided into three groups: (1) control, (2) SAH without exercise, and (3) SAH plus mild exercise. On day 5, brainstems were removed and analyzed for the injury marker inducible nitric oxide synthase (iNOS). RESULTS: Clinical: Mild exercise before day 4 significantly lowered the incidence of symptomatic CV compared with the nonexercised group. There was no difference in the incidence of additional complications based upon exercise. Laboratory: Staining for iNOS was significantly higher in the SAH group than the control group, but there was no difference between exercised and nonexercised SAH groups, confirming that exercise did not promote neuronal injury. CONCLUSION: Early mobilization significantly reduced clinical CV. The relationship should be studied further in a prospective trial with defined exercise regimens.

Time-dependent changes in cerebrospinal fluid metal ions following aneurysm subarachnoid hemorrhage and their association with cerebral vasospasm.

Aneurysm subarachnoid hemorrhage affects 10 in 100,000 people annually, 40 % of whom will develop neurological deficits from ischemic stroke caused by cerebral vasospasm. Currently, the underlying mechanisms are uncertain. Metal ions are important modulators of neuronal electrophysiological conduction and smooth muscle cell activity, thereby potentially contributing to vasospasm. We hypothesized that metal ion concentrations in the cerebrospinal fluid (CSF) after aneurysm rupture would change over time and be associated with vasospasm. To test this hypothesis, for 21 days, we collected CSF from patients with aneurysmal rupture and subjected it to spectrometry to detect metals. A repeated measures analysis was performed to analyze concentration changes over time. Six of the seven patients with aneurysmal rupture experienced vasospasm, all resolving by day 14. Changes in Fe²âº and Zn²âº concentrations in the CSF paralleled the incidence of vasospasm in this study population. Na²âº, Ca²âº, Mg²âº, and Cu²âº concentrations exhibited no statistically significant changes over time. In conclusion, Fe²âº concentration in the CSF was significantly elevated during days 7-10, whereas Zn²âº concentrations spiked shortly thereafter, during days 11-14. This suggests that Fe²âº may be related to the induction of vasospasm and Zn²âº may be a marker of early brain injury secondary to ischemic injury and inflammation.

Tracheostomy timing affects stroke recovery.

BACKGROUND: The timing of tracheostomy in stroke patients unable to protect their airway has become a topic of debate. Proponents for early tracheostomy (ET) cite benefits including less ventilation-associated pneumonia, less sedative drug use, shorter length of stay, and reduced mortality in comparison with late tracheostomy (LT). METHODS: We examined the timing of tracheostomy on stroke patient outcomes across the United States using the Nationwide Inpatient Sample (2008-2010). Independent samples t tests and chi-squared tests were used to make comparisons between early (≤10 days) and late (11-25 days) tracheostomy. Multivariable models, adjusted for confounding factors, investigated outcome measures. RESULTS: In total, 13,165 stroke cases were included in the study (5591 in the ET group and 7574 in the LT group). Patients receiving an ET had a significant reduction in the odds of ventilator-associated pneumonia in comparison with the LT group (OR: .688, P = .026). The length of stay for patients receiving an ET was significantly lower in comparison with the LT group (P < .001) and was associated with an 18% reduction in total hospital costs (P < .001). CONCLUSIONS: Early tracheostomy for stroke patients may reduce the incidence of ventilator-associated pneumonia, thereby shortening the hospital stay and lowering total hospital costs. These relationships warrant further investigation in a large prospective multicenter trial.

Stenting versus endarterectomy and the impact of ultra-early revascularization for emergent admissions of carotid artery stenosis.

BACKGROUND: The factors influencing outcomes after emergent admission for symptomatic carotid artery stenosis treated with revascularization by endarterectomy or stenting are yet to be fully elucidated. METHODS: We analyzed revascularization of carotid artery stenosis for patients admitted emergently using the Nationwide Inpatient Sample (2008-2011). Admission characteristics, economic measures, in-hospital mortality, and iatrogenic stroke were compared between (1) endarterectomy and stenting, (2) patients with and without cerebral infarction, and (3) ultra-early (within 48 hours of admission) and deferred (up to 2 weeks) intervention. RESULTS: 72,797 admissions meeting our inclusion criteria were identified. Factors associated with ultra-early revascularization were male patients, low comorbidity burden, stenosis without infarction, and stenting. Ultra-early intervention significantly decreased cost and length of stay, and stenting for patients without infarction decreased length of stay but increased cost. Patients without infarction treated within 48 hours had significantly lower mortality and iatrogenic stroke rate. Patients with infarction receiving ultra-early revascularization had increased odds of mortality and iatrogenic stroke in comparison with the deferred group. Patients with infarction receiving stenting experienced increased odds of mortality in comparison with those receiving endarterectomy, but there was no significant difference in iatrogenic stroke rate. Recombinant tissue plasminogen activator (rtPA) administration on the day of revascularization greatly increased the odds of iatrogenic stroke and mortality. CONCLUSIONS: Larger prospectively randomized trials evaluating the optimum timing of revascularization after emergent admission of carotid artery stenosis seem warranted.

Controversies in the role of preoperative embolization in meningioma management.

The role of preoperative embolization in meningioma management remains controversial, even though 4 decades have passed since it was first described. It has been shown to offer benefits such as decreased blood loss and "softening of the tumor" during subsequent resection. However, the actual benefits remain unclear, and the potential harm of an additional procedure along with the cost of embolization have limited its use to a small proportion of the meningiomas treated. In this article the authors retrospectively reviewed their experience with preoperative embolization of meningiomas over the previous 6 years (March 2007-March 2013). In addition, they performed a MEDLINE search using a combination of the terms "meningioma," "preoperative," and "embolization" to analyze the indications, embolizing agents, timing, and complications reported during preoperative embolization of meningiomas. In this retrospective review, 18 cases (female/male ratio 12:6) were identified in which endovascular embolization was used prior to resection of an intracranial meningioma. Craniotomy for tumor resection was performed within 4 days after endovascular embolization in all cases, with an average time to surgery of 1.9 days. The average duration of surgery was 4 hours and 18 minutes, and the average blood loss was 574 ml, with a range of 300-1000 ml. Complications following endovascular therapy were identified in 3 (16.7%) of 18 cases, including one each of transient hemiparesis, permanent hemiparesis, and tumor swelling. The literature review returned 15 articles consisting of a study population greater than 25 patients. No randomized controlled study was found. The use of small polyvinyl alcohol particles (45-150 µm) is more effective in preoperative devascularization than larger particles (150-250 µm), but is criticized due to the higher risk of complications such as cranial nerve palsies and postprocedural hemorrhage. Time to surgery after embolization is inconsistently reported across the articles, and conclusions on the appropriate timing of surgery could not be drawn. The overall complication rate reported after treatment with preoperative meningioma embolization ranges from as high as 21% in some of the older literature to approximately 6% in recent literature describing treatment with newer embolization techniques. The evidence in the literature supporting the use of preoperative meningioma embolization is mainly from case series, and represents Level III evidence. Due to the lack of randomized controlled clinical trials, it is difficult to draw any significant conclusions on the overall usefulness of preoperative embolization during the management of meningiomas to consider it a standard practice.

Aneurysm embolization grade: a predictive tool for aneurysm recurrence after coil embolization.

BACKGROUND: Coil embolization has gained importance in the management of intracranial aneurysms over the past decade. However, the recurrence risk after embolization mandates closer follow-up than surgical clip ligation. Currently, there is no reliable system for predicting aneurysm sac thrombosis. An aneurysm embolization grade (AEG) reported previously by the senior author (EMD) has been proposed as a tool for predicting the durability of aneurysm occlusion based on hemodynamic characteristics. Here, we present our internal validity results. METHODS: AEG and Raymond-Roy Occlusion Classification (RROC) scores were prospectively assigned to all aneurysms coiled from June 2008 to June 2011. The prospectively assigned AEG and RROC scores from the cerebral angiograms were collected for data analysis and validity assessment of the AEG system. 110 consecutive patients who had aneurysm coil embolization were included in this study. RESULTS: The post-coiling AEG significantly predicted follow-up angiographic filling characteristics. Pairwise comparisons revealed that the follow-up AEG for those initially scored 'A' (complete obliteration) was significantly better than the contrast-flow groups. Significant differences were also noted between contrast-stasis and contrast-flow groups. A pairwise comparison between RROC scores demonstrated that only the RROC Type 1 could be used to predict follow-up occlusion durability. Stent placement in wide-neck aneurysms had no effect on initial AEG, RROC, or long-term occlusion durability. Packing density significantly predicted initial AEG and RROC, but had no effect on long-term occlusion. CONCLUSIONS: The AEG system is uniquely based on angiographic filling characteristics of the aneurysm, and this study demonstrated its high predictive value for determining aneurysm sac thrombosis. Assigning an AEG to the aneurysm can guide the neurointerventionalist in discussions with the patient regarding the probability of aneurysm recurrence and potential need for retreatment.

Direct cortical stimulation but not transcranial electrical stimulation motor evoked potentials detect brain ischemia during brain tumor resection.

Motor evoked potentials (MEPs) elicited by both direct cortical stimulation (DCS) and transcranial electrical stimulation are used during brain tumor resection. Parallel use of direct cortical stimulation motor evoked potentials (DCS-MEPs) and transcranial electrical stimulation motor evoked potentials (TCeMEPs) has been practiced during brain tumor resection. We report that DCS-MEPs elicited by direct subdural grid stimulation, but not TCeMEPs, detected brain ischemia during brain tumor resection. Following resection of a brainstem high-grade glioma in a 21-year-old, the threshold of cortical motor-evoked-potentials (cMEPs) increased from 13 mA to 20 mA while amplitudes decreased. No changes were noted in transcranial motor evoked potentials (TCMEPs), somatosensory evoked potentials (SSEPs), auditory evoked potentials (AEPs), anesthetics, or hemodynamic parameters. Our case showed the loss of cMEPs and SSEPs, but not TCeMEPs. Permanent loss of DCS-MEPs and SSEPs was correlated with permanent left hemiplegia in our patient even when appropriate action was taken. Parallel use of DCS- and TCeMEPs with SSEPs improves sensitivity of intraoperative detection of motor impairment. DCS may be superior to TCeMEPs during brain tumor resection.

Postoperative Management of Anterior Visual Pathway Cavernoma, a Unique Perspective: Case Report.

Cavernous malformations (CMs) are low-flow vascular lesions with an incidence of 0.1% to 0.7% in the general population. Less than 1% are found in the anterior visual pathway. The most common presenting symptoms are visual disturbances due to hemorrhage and the current standard of treatment is gross total resection. The authors report a case of a 42-year-old male with visual disturbance and findings on T1-weighted magnetic resonance imaging (MRI) suggesting CM of the right optic nerve and right optic chiasm. The patient underwent right pterional craniotomy for gross total resection of the lesion. One year postoperatively, the patient demonstrated improvement in visual deficits with no signs of recurrence on MRI. Thirty-two months postresection, MRI showed a small slightly lobulated area of T1 hyperintense material within the postoperative cavity along the right aspect of the optic chiasm. MRI at 39 months postresection showed previously seen small amounts of T1 hyperintensity in the central and right aspect of the optic chiasm, with significantly decreased conspicuity. These findings suggest a trace amount of recurrence in the 32-month postoperative imaging despite overall stable visual field testing. There is a paucity of literature concerning the retreatment of resected CM in the anterior visual pathway. The authors suggest serial imaging as an integral component of CM management. Although repeated visual field testing and clinical follow-up are important aspects of CM management, they are no substitute for the gold standard of MRI.

Clinical and Economic Impact of Time From Admission for CSF Rhinorrhea to Surgical Repair.

BACKGROUND: If conservative management of CSF leak is unsuccessful, surgical repair is indicated for the prevention of severe complications such as meningitis. This study investigated the influence of surgical timing on clinical and economic outcomes. METHODS: Retrospective review of the National Inpatient Sample (2012) and the Nationwide Inpatient Sample (2002-2011) for nonelective admissions with a principal diagnosis of CSF rhinorrhea treated with surgical repair of the meninges. Demographics and outcomes of patients undergoing meningeal repair for CSF rhinorrhea were analyzed. Cases were classified into four groups based on timing of surgical intervention: 1) performed on the day of admission (day 0), 2) performed between days 1 and 3, 3) performed between days 4 and 7, and 4) performed between days 8 and 14. RESULTS: A total of 1,088 emergent admissions were analyzed. On average, patients underwent surgical repair between the second and fourth day of admission. Lowest rates of meningitis were in patients treated on the day of admission (6.1%); those treated at 2 weeks had a 34.7% incidence. Multivariate analysis controlling for comorbidity burden, gender, and surgical timing found the highest odds of meningitis in patients treated with surgical repair during the second week of admission compared to repair on the day of admission (OR 8.2, P < .001). Length of stay (LOS) and hospital costs increased as time to repair increased. CONCLUSION: Multiple factors influence outcomes in patients with CSF rhinorrhea. Early surgical repair was significantly associated with decreased rates of meningitis, LOS, and hospital costs. Expedient treatment of patients admitted for CSF rhinorrhea may prove to be both a cost- and morbidity-saving measure. LEVEL OF EVIDENCE: 2C Laryngoscope, 129:539-543, 2019.

Emergency decompressive craniectomy for fulminating infectious encephalitis.

In patients who develop fulminant cerebral edema and elevated intracranial pressures, viral encephalitis can result in devastating neurological and cognitive sequelae despite antiviral therapy. The benefits of decompressive craniectomy, if any, in this group of patients are unclear. In this manuscript, the authors report their experience with 2 patients who presented with herpes simplex virus requiring surgical decompression resulting in excellent neurocognitive outcomes. They also review the literature on decompressive craniectomy in patients with fulminating infectious encephalitis. Four published articles consisting of 13 patients were identified in which the authors had reported their experience with decompressive craniectomy for fulminant infectious encephalitis. Herpes simplex virus was confirmed in 6 cases, Mycoplasma pneumoniae in 2, and an unidentified viral infection in 5 others. All patients developed clinical signs of brainstem dysfunction and underwent surgical decompression resulting in good (Glasgow Outcome Scale [GOS] Score 4) or excellent (GOS Score 5) functional recoveries. The authors conclude that infectious encephalitis is a neurosurgical disease in cases in which there is clinical and imaging evidence of brainstem compression. Surgical decompression results in excellent recovery of functional independence in both children and adults despite early clinical signs of brainstem dysfunction.

A prospective single-center analysis of the safety and efficacy of the hydrocoil embolization system for the treatment of intracranial aneurysms.

OBJECT: The HydroCoil embolization system is a helical platinum coil coated with a polymeric hydrogel that expands when it contacts aqueous solutions to increase filling volumes, improve mesh stability, and possibly elicit a healing response within the aneurysm. In this paper, the authors report the 1-year recurrence and complication rates of 67 aneurysms embolized with the HydroCoil system. METHODS: Sixty-four consecutive patients (67 total aneurysms) with small (< or =7 mm), large (8-15 mm), very large (16-24 mm), and giant (> or =25 mm) aneurysms in the anterior and posterior intracranial circulations were treated with HydroCoils between March 2003 and September 2004. All aneurysms were embolized by the senior author (A.S.B) with HydroCoils alone or in combination with bare platinum coils, until either there was no further angiographic contrast filling of the aneurysm or the microcatheter was pushed out of the dome by the coil mass. Balloon assistance was used in three cases and combined Neuroform stent-coil embolization in eight other cases. To evaluate the safety and 1-year efficacy of the HydroCoil system, periprocedural complications were recorded, and angiographic recurrences were categorized using the Raymond-Roy Occlusion Classification (RROC) system. The 1-year aneurysm recurrence rate independent of size was 15% in patients treated with HydroCoils. Seventy percent of the patients had stable occlusions. The recurrence rate for small aneurysms was 3.7%, and the combined recurrence rate for small and large aneurysms was 6%. Fifteen percent of the aneurysms initially categorized as RROC Type 2 or 3 with stasis of contrast material at the time of initial embolization improved in RROC type, allowing the authors to develop the aneurysm embolization grade to predict recurrence. The neurological complication rate was 14.9%, of which 4.5% represented permanent neurological deficits. CONCLUSIONS: The HydroCoil embolization system is safe and provides excellent 1-year occlusion of small and large aneurysms with initial RROC Type 1, as well as those with RROC Types 2 and 3 with stasis of contrast material at the time of embolization. Very large and giant aneurysms were not as successfully occluded with this system. Treatment of large and giant internal carotid artery aneurysms was more likely to result in cranial nerve palsies and postembolization headaches than treatment in other locations. The aneurysm embolization grade the authors developed using the results of this study accurately predicted 1-year recurrence rates based on the immediate postembolization angiographic characteristics of the treated aneurysm.

Trends in mortality following mechanical thrombectomy for the treatment of acute ischemic stroke in the USA.

BACKGROUND AND PURPOSE: Mechanical thrombectomy (MT) for the treatment of acute ischemic stroke has been growing in popularity while the therapeutic benefit of MT has been increasingly debated. Our objective was to examine national trends in mortality following MT. METHODS: We analyzed the National Inpatient Sample (2012) and the Nationwide Inpatient Sample (2008-2011) for patients with a primary diagnosis of acute ischemic stroke that received MT. Temporal trends in mortality were examined using Spearman's rank correlation. To account for confounding factors, mortality was further analyzed in binary logistic regression. RESULTS: Hospitals performing MT comprised 8% of all hospitals treating ischemic stroke. The percentage of stroke cases treated with MT increased from 0.6% of cases in 2008 to 1.1% in 2012, totaling 16 307 MT cases in a 5 year period. Inhospital mortality decreased over the study period from 25.4% in 2008 to 16.1% in 2012 (r=-0.081, p<0.001). This finding was supported by regression analysis as each incremental year reduced the odds of mortality by 20% (OR=0.832, p<0.001). Administration of recombinant tissue plasminogen activator was associated with a decrease in the odds of mortality (OR=0.805, p<0.001). CONCLUSIONS: Utilization of MT represents a small percentage of stroke cases, although the trend is increasing. Mortality following MT has been showing a steady decline over the past 5 years. This may be a result of a learning curve, improved patient selection, and/or device improvements. Randomized trials remain essential to evaluate the potential benefit of endovascular devices and identify the most appropriate patients.

Refractory Thoracolumbar Cerebrospinal Fluid Leak after Multiple Spinal Ependymoma Resections Treated with External Ventricular Drainage.

Study Design Case report. Objective Temporary external ventricular drainage for refractory thoracolumbar cerebrospinal fluid (CSF) leak is not reported in the literature. We describe a recent case that utilized this technique. Methods Retrospective review of the patient's case notes was performed and the literature on this subject reviewed. Results The patient underwent multiple complex spinal surgeries for resection of innumerable metastatic ependymoma lesions. A case of significant refractory CSF leak developed and as a last resort a right frontal external ventricular drain was placed. The CSF leak ceased, and the patient was eventually discharged home without further complication. Conclusion External ventricular drainage can be a viable option for temporary proximal CSF diversion to treat refractory thoracolumbar CSF leaks.

Primary Angioplasty Versus Stenting for Endovascular Management of Intracranial Atherosclerotic Disease Following Acute Ischemic Stroke.

BACKGROUND: The future of neuroendovascular treatment for intracranial atherosclerotic disease (ICAD) has been debated since the results of SAMMPRIS reflected poor outcomes following endovascular therapy. There is currently a large spectrum of current management strategies. We compared historical outcomes of patients with ICAD and stroke that were treated with angioplasty-alone versus stent placement. METHODS: We extracted a population from the Nationwide Inpatient Sample (NIS) (2005-2011) and the National Inpatient Sample (NIS) (2012) composed of patients with ICAD and infarction that were admitted nonelectively and received endovascular revascularization. Patients treated with thrombectomy or thrombolysis were excluded. Categorical variables were compared with Chi-squared tests. Binary logistic regression was performed to evaluate mortality while controlling for age, sex, severity, and comorbidities. RESULTS: About 2059 admissions met our criteria. A majority were treated via stent placement (71%). Angioplasty-alone had significantly higher mortality (17.6% vs. 8.4%, P<0.001), but no difference in iatrogenic stroke rate (3.4% vs. 3.6%, P=0.826), compared to stent placement. The adjusted odds ratio of mortality for stented patients was 0.536 (95% CI: 0.381-0.753, P<0.001) in comparison to patients treated with angioplasty alone. CONCLUSIONS: This study found the risk of mortality to be elevated following angioplasty alone in comparison to revascularization with stent placement, without a corresponding significant difference in iatrogenic stroke rate. This may represent selection bias due to patient characteristics not defined in the database, but it also may indicate that patients with ICAD and acute stroke have increased odds of stenosis that is refractory to angioplasty alone and have a high risk of mortality without revascularization.

Intradural Carcinoid Tumor Found in a Patient with No History of Cancer.

BACKGROUND: Carcinoid tumors are rare neoplasms that often arise from the gastrointestinal or respiratory tracts. They often metastasize to bone tissue and pancreatic and hepatic sites. The central nervous system and most specifically the spinal cord are rarely involved. Primary carcinoid tumors of the central nervous system are even rarer. CASE DESCRIPTION: A 58-year-old man presented with progressive bilateral lower extremity weakness and a negative history of cancer. Imaging revealed an intradural mass at the L1 and L2 spinal levels. Surgical resection of the tumor via laminectomy was performed. The tumor was observed to have eroded through the dura and was compressing the spinal nerves. Histopathologically, the mass was observed to be of carcinoid origin. A subsequent octreoscan revealed no primary sites of carcinoid tumor. Postoperatively, the patient was followed for 1.5 years. The patient reported improvement in sensation to his lower extremities with no change in motor findings. CONCLUSIONS: Carcinoid tumors of the central nervous system are extremely rare, but they should remain in the differential diagnosis for patients experiencing extremity weakness and back or neck pain with an intradural mass and no primary source of the tumor identified or other manifestations of a primary tumor.

Coronary angiojet catheterization for the management of dural venous sinus thrombosis. Technical note.

In most cases of deep venous sinus thrombosis, systemic anticoagulation represents the initial treatment of choice for preventing propagation of a clot in the dural sinuses. In patients with deep or extensive venous sinus thrombosis, a combination of treatment modalities may be required including systemic anticoagulation, selective venous thrombolysis, and mechanical thrombectomy. In the current study the authors report on a patient who presented with the acute onset of headache, vomiting, a depressed level of consciousness, and a left hemiparesis and in whom a right middle cerebral artery (MCA) territory ischemic stroke with hemorrhagic conversion was initially diagnosed. Results of diagnostic cerebral angiography demonstrated a patent right MCA and a deep venous sinus thrombosis involving most of the dural sinuses. Despite adequate systemic heparinization, the patient's neurological condition deteriorated and direct administration of alteplase into the transverse sinus in conjunction with mechanical clot disruption using a coronary AngioJet was required. Venous flow was successfully reestablished in the deep and superficial venous sinuses by using a 0.014-in exchange wire routed from the right common femoral vein through the sinuses and out the left common femoral vein. Excellent angiographic results were obtained, and the patient had recovered completely by the 7-month follow up.

A triple bifurcation aneurysm model for evaluating complex endovascular therapies in dogs.

OBJECT: Animal aneurysm models are required for the study of the hemodynamics and pathophysiology of intracranial aneurysms in humans and so that experimental treatments can be tested prior to clinical trials. The authors developed a canine model that consistently produces up to three bifurcation aneurysms similar in morphological features and hemodynamics to human intracranial aneurysms. METHODS: In 10 mongrel dogs, a harvested segment of the external jugular vein was anastamosed to an external carotid artery (CA)-lingual artery bifurcation arteriotomy site to create a lateral bifurcation aneurysm. The surgery was repeated on the contralateral side in each animal to form a second lateral bifurcation aneurysm and, in five dogs, a CA-CA crossover anastomosis was also performed to create a terminal bifurcation aneurysm. Nineteen of 20 lateral bifurcation aneurysms were confirmed in 10 dogs by diagnostic angiography 7 to 14 days after surgery. Aneurysm fundus-to-neck ratios ranged from 1 to 2, depending on the size of the arteriotomy. The terminal bifurcation aneurysms were confirmed in all five dogs by diagnostic angiography 7 to 14 days after the procedure. The authors later tested endovascular techniques for embolizing the aneurysms. CONCLUSIONS: Three bifurcation aneurysms of sufficient size for endovascular access can be created in a reproducible fashion in the same animal. This model is useful for studying complex endovascular procedures in aneurysms that mimic the human condition and for testing new devices and techniques.

Preliminary evidence supporting the safety of drug-eluting stents in neurovascular disease.

OBJECTIVE: Restenosis is a significant complication of stent placement. With coronary revascularization, drug-eluting stents have significantly decreased the incidence of in-stent stenosis and, therefore, the morbidity of the procedure. Restenosis is potentially a significant problem for neurovascular disease. We therefore report our institutional experience on the use of drug-eluting stents for the management of cerebrovascular insufficiency. METHODS: Over a period of 2 years, 19 patients underwent extra- and intracranial drug-eluting stent placement for intra- and extracranial atherosclerotic disease. There were 12 males and seven females aged between 36 and 83 years old (mean 65). Thirteen heparin, three rapamycin, and three taxus-coated stents were placed. There were five intracranial internal carotid arteries, two intracranial vertebral arteries, three mid-basilar, six of vertebral artery origin and three middle cerebral artery stents utilized. No complications occurred. RESULTS: There was one case of re-stenosis associated with recurrent symptoms requiring repeat drug eluting stent placement. No other patients have developed new or recurrent neurological symptoms. Five of six vertebral artery origin stents were placed with distal protection to prevent embolic complications. CONCLUSION: Intracranial and extracranial drug-eluting stent placement appears to be a safe alternative to the medical management of atherosclerotic disease of the vertebrobasilar and carotid systems. However, further randomized studies are needed to examine the effectiveness and safety of this procedure.