Pivotal trial of the Neuroform Atlas stent for treatment of posterior circulation aneurysms: one-year outcomes.

BACKGROUND: Stent-assisted coiling of wide-necked intracranial aneurysms (IAs) using the Neuroform Atlas Stent System (Atlas) has shown promising results. OBJECTIVE: To present the primary efficacy and safety results of the ATLAS Investigational Device Exemption (IDE) trial in a cohort of patients with posterior circulation IAs. METHODS: The ATLAS trial is a prospective, multicenter, single-arm, open-label study of unruptured, wide-necked, IAs treated with the Atlas stent and adjunctive coiling. This study reports the results of patients with posterior circulation IAs. The primary efficacy endpoint was complete aneurysm occlusion (Raymond-Roy (RR) class I) on 12-month angiography, in the absence of re-treatment or parent artery stenosis >50%. The primary safety endpoint was any major ipsilateral stroke or neurological death within 12 months. Adjudication of the primary endpoints was performed by an imaging core laboratory and a Clinical Events Committee. RESULTS: The ATLAS trial enrolled and treated 116 patients at 25 medical centers with unruptured, wide-necked, posterior circulation IAs (mean age 60.2±10.5 years, 81.0% (94/116) female). Stents were placed in all patients with 100% technical success rate. A total of 95/116 (81.9%) patients had complete angiographic follow-up at 12 months, of whom 81 (85.3%) had complete aneurysm occlusion (RR class I). The primary effectiveness outcome was achieved in 76.7% (95% CI 67.0% to 86.5%) of patients. Overall, major ipsilateral stroke and secondary persistent neurological deficit occurred in 4.3% (5/116) and 1.7% (2/116) of patients, respectively. CONCLUSIONS: In the ATLAS IDE posterior circulation cohort, the Neuroform Atlas Stent System with adjunctive coiling demonstrated high rates of technical and safety performance. Trial registration number https://clinicaltrials.gov/ct2/show/NCT02340585.

Neuroform Atlas Stent for Treatment of Middle Cerebral Artery Aneurysms: 1-Year Outcomes From Neuroform Atlas Stent Pivotal Trial.

BACKGROUND: Heterogeneous effect of endovascular aneurysm therapy has been observed across different anatomic locations. There is a paucity of data for stent-assisted coiling of middle cerebral artery (MCA) aneurysms. OBJECTIVE: To present the results of the MCA aneurysm group from the Neuroform Atlas (Stryker Neurovascular) investigational device exemption (IDE) trial. METHODS: The Atlas IDE trial is a prospective, multicenter, single-arm, open-label study of wide-neck aneurysms (neck ≥ 4 mm or dome-to-neck ratio < 2) in the anterior circulation treated with the Neuroform Atlas Stent and approved coils. Follow-up was obtained immediately postprocedure and 2, 6, and 12 mo postoperatively. We herein describe safety and efficacy outcomes, and functional independence of the subjects with aneurysms from all segments of MCA. RESULTS: A total of 35 patients were included (27 MCA bifurcation, 5 M1, 3 M2). The mean aneurysm size was 6.0 ± 1.8 mm, and the mean neck was 4.4 ± 1.2 mm. Technical procedural success was achieved in all patients. A total of 26 patients had follow-up digital subtraction angiography available at 12 mo, with 80.8% (21/26) having complete aneurysm occlusion. Twelve-month safety data were collected for 91.4% (32/35), 8.5% (3/35) had primary safety endpoint, all 3 major ischemic strokes. Mortality occurred in 2 patients beyond 30 d unrelated to procedure (1 gallbladder cancer and 1 fentanyl intoxication). At 1 yr, modified Rankin Score was 0 to 2 in 84.4% (27/32), 3 in 9.4%, and 3 patients were missing. Approximately 5.7% (2/35) of patients were retreated at 12 mo. CONCLUSION: Stent-assisted coiling with the Neuroform Atlas Stent is a viable alternative to clipping for selected MCA aneurysms. Complete aneurysm occlusion rates have improved compared to historical data. Proper case selection can lead to acceptable endovascular results.

Carotid cavernous fistula (CCF) treatment approaches: A systematic literature review and meta-analysis of transarterial and transvenous embolization for direct and indirect CCFs.

BACKGROUND: Carotid Cavernous Fistulas (CCFs) are the result of an abnormal communication between the carotid artery and its branches and the venous system of the cavernous sinus. The mainstay of therapy for CCFs consists of transarterial or transvenous embolization, while other treatment options such as open surgery or radiosurgery are still utilized as second-line or adjuvant therapeutic options. OBJECTIVE: Our aim was to systematically review and summarize available data regarding short- and long-term outcomes of all available treatment modalities for CCFs. METHODS: This systematic review was conducted according to the PRISMA guidelines. A random effects model meta-analysis was conducted. RESULTS: Fifty-seven studies comprising 1575 patients were included in this systematic review. Transarterial embolization for direct and indirect CCFs offered a complete obliteration rate of 93.93% (N = 589/627) and 81.51% (N = 119/146), respectively. Transvenous embolization for direct and indirect lesions achieved obliteration in 91.67% (N = 33/36) and 86.03% (N = 425/494) of patients, respectively. Comparison between transarterial and transvenous embolization did not reveal statistically significant differences in terms of fistula obliteration for direct (OR: 1.42; 95% CI: 0.23-8.90; I2 0.0%) and indirect CCFs (OR: 0.62; 95% CI: 0.31-1.23; I2 0.0%). CONCLUSIONS: Endovascular embolization techniques are the preferred treatment modality for the management of CCFs. No differences were identified between transarterial and transvenous embolization by synthesizing studies with available data. Future prospective cohorts are warranted to compare the different materials and techniques implemented especially within the rapidly expanding realm of endovascular approaches.

Neurologic Complications in Patients with Left Ventricular Assist Devices: Single Institution Retrospective Review.

BACKGROUND: Neurologic complications are common complications encountered by patients with left ventricular assist devices (LVADs). This single-center retrospective study aims to identify the incidence and risk factors of neurologic complications and interventions in patients supported with LVADs and define the associated anticoagulation management. METHODS: Between August 2009 and August 2017, 244 patients underwent LVAD implantation. Twenty-one patients were excluded for having neurologic complications before LVAD placement or for having previously undergone heart transplantation. RESULTS: Fifty-six patients (25%) suffered 61 complications, and 11 (19.6%) died as a result. Gender, type of LVAD, or chronic medical comorbidities evaluated did not contribute to a difference in complication rate; in contrast, length of LVAD implantation was directly related to risk of neurologic complication. Eleven patients (19.6%) underwent 13 surgical interventions including 5 mechanical thrombectomies. Anticoagulation was reversed in 16 patients and held without complication. Anticoagulation was not held for ischemic complications, and no clinically significant hemorrhagic transformation occurred. Intravenous tissue plasminogen activator was also successfully administered to 3 patients without complication. CONCLUSIONS: Neurologic complications were observed in 25% of patients supported with LVADs, of which 20% required neurosurgical intervention. Anticoagulation can be safely withheld in patients with hemorrhagic complications. Patients with ischemic complications can continue to be anticoagulated with no significant risk of hemorrhagic transformation. Length of LVAD implantation was directly related to the risk of neurologic complication. Finally, our study adds to existing literature that mechanical thrombectomy and even intravenous tissue plasminogen activator are options for LVAD patients with ischemic complications.

Prevalence of carotid stenosis following radiotherapy for head and neck cancer: A systematic review and meta-analysis.

BACKGROUND: Radiation to the head and neck is a well-established risk factor for the development of carotid artery stenosis. Our objective was to identify the prevalence, incidence, and degree of carotid stenosis in patients with a history of head and neck irradiation. METHODS: This study was performed according to the PRISMA guidelines. A random effects model meta-analysis was conducted. RESULTS: Nineteen studies comprising 1479 patients were included. The prevalence of carotid stenosis >50%, >70%, and carotid occlusion was 25% (95% CI: 19%-32%), 12% (95% CI: 7%-17%), and 4% (95% CI: 2%-8%), respectively. The cumulative 12-month incidence of carotid stenosis >50% was 4% (95% CI: 2%-5%), the 24-month was 12% (95% CI: 9%-15%), and the 36-month was 21% (95% CI: 9%-36%). CONCLUSIONS: The yearly incidence of carotid stenosis >50% increased every year during the first 3 years following radiotherapy. We propose routine yearly Doppler ultrasound screening beginning 1 year after head and neck radiotherapy.

Endovascular reconstruction of extracranial traumatic internal carotid artery dissections: a systematic review.

Extracranial internal carotid artery dissection (ICAD) is a potential source of morbidity and mortality in trauma patients and requires high degree of suspicion for diagnosis after the initial presentation. Occasionally, if standard therapy is contraindicated, endovascular reconstruction is a treatment option. The aim of this systematic review was to report clinical and radiographic outcomes following endovascular repair of ICAD of traumatic and iatrogenic etiology. A comprehensive systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. PubMed and Cochrane Library databases were searched. Twenty-four studies comprising 191 patients (204 lesions) were included; 179 underwent traditional carotid artery stenting (CAS), whereas 12 patients underwent flow diversion with the pipeline embolization device (PED). In total, 75.7% of the CAS group and 66.6% of the PED group presented with ICAD-related symptomatology. Concomitant pseudoaneurysms were identified in 61.9% and 78.5% of lesions in the CAS and PED group, respectively. Adverse event rates among CAS-treated lesions after 30-day follow-up were below 2.2% for stroke, transient ischemic attack, and mortality. During follow-up in the CAS group, there was no incidence of ICAD-related stroke or death and 2.2% of patients underwent a repeat CAS procedure. In the PED group, no patient suffered stroke or death in the reported follow-up. In the PED cohort, there was an adequate occlusion rate and no patient had to be retreated. Endovascular reconstruction of traumatic or iatrogenic ICAD appears safe. This approach demonstrated acceptable short- and long-term clinical and radiographic outcomes in both groups.

Risk Factors for Restenosis After Carotid Revascularization: A Meta-Analysis of Hazard Ratios.

BACKGROUND: Carotid artery restenosis after carotid endarterectomy (CEA) or carotid artery stenting (CAS) will occur in 3%-30% of cases. Restenosis can lead to more frequent clinical and imaging monitoring and the potential for reoperation. We sought to define the demographic, clinical, and radiographic characteristics that influence the restenosis risk after carotid revascularization. METHODS: The present study was performed in accordance with the PRISMA (preferred reporting items for systematic reviews and meta-analyses) guidelines. A random effects model meta-analysis of hazard ratios (HRs) was conducted. RESULTS: Eighteen studies with 17,106 patients were included. Diabetes (HR, 1.68; 95% confidence interval [CI], 1.00-2.83; I2, 76.7%), dyslipidemia (HR, 1.77; 95% CI, 1.08-2.91; I2, 22.5%), female gender (HR, 1.50; 95% CI, 1.14-1.98, I2, 0%), chronic kidney disease (HR, 4.15; 95% CI, 1.69-10.19; I2, 44.5%), hypertension (HR, 1.99; 95% CI, 1.07-3.72; I2, 68%), smoking (HR, 1.65; 95% CI, 1.15-2.37; I2, 54.3%), and pretreatment stenosis >70% (HR, 1.04; 95% CI, 1.0-1.08; I2, 0%) showed a statistically significant increase in restenosis risk after carotid revascularization. Subgroup analyses of CEA and CAS showed that female gender and smoking status were significantly associated with recurrent stenosis after CEA but not after CAS. In contrast, hypertension was associated with restenosis after CAS but not after CEA. Patch endarterectomy (HR, 0.33; 95% CI, 0.22-0.50; I2, 0%) and symptomatic status at presentation in the CAS group (HR, 0.61; 95% CI, 0.41-0.90; I2, 0%) were associated with a decreased risk of restenosis. Antiplatelet use and coronary artery disease were not associated with restenosis risk. CONCLUSIONS: Diabetes, dyslipidemia, female gender, renal failure, hypertension, and smoking were associated with an increased risk of restenosis, and patch endarterectomy and symptomatic status at presentation were associated with a decreased risk of carotid restenosis. Both female gender and current smoking status were only associated with recurrent stenosis after CEA, and hypertension was only associated with restenosis after CAS.

De Novo Spinal Dural Arteriovenous Fistula in a Patient with a Lipomyelomeningocele: Case Report.

BACKGROUND: Spinal dural arteriovenous fistula (AVF), the most common type of spinal vascular malformation, tends to manifest as progressive myelopathy over several years. Spinal dural AVFs are considered an acquired lesion and, in contrast to spinal arteriovenous malformations, are not often associated with other anomalies. The presence of a spinal dural AVF in the setting of a lipomyelomeningocele and tethered cord is extremely rare. Both lesions tend to cause similar symptoms, and patients with concomitant lesions generally require surgical intervention for both. CASE DESCRIPTION: A 57-year-old female with lifelong urinary incontinence and mild weakness in the left lower extremity presented with progressive worsening of left lower extremity weakness as well as worsening bowel and bladder incontinence. Magnetic resonance imaging (MRI) performed 4 years before our evaluation revealed a lipomyelomeningocele and a tethered cord; a new MRI demonstrated a new additional finding of flow voids suspicious of an underlying vascular malformation. Diagnostic angiography revealed a dural AVF fed by a left lateral sacral artery. Onyx embolization of the dural AVF was performed, and the patient improved steadily postoperatively without the need for surgically addressing the tethered cord. CONCLUSION: In this case report, we present evidence of de novo development of a spinal dural AVF associated with a lipomyelomeningocele. In addition, this is the second documented patient in the literature with a lipomyelomeningocele and concomitant dural AVF who did not undergo detethering of the cord as part of treatment.

Pipeline Embolization Device for treatment of high cervical and skull base carotid artery dissections: clinical case series.

BACKGROUND: Most cervical dissections are treated with anticoagulation or antiplatelet agents with very good results; however, some patients may benefit from endovascular intervention. High cervical and skull base dissections are often more challenging to treat because of the distal location and tortuous anatomy. The Pipeline Embolization Device (PED) may be a reasonable treatment option for this indication. OBJECTIVES: To report a case series of patients treated with the PED for high cervical and skull base dissections, focusing on their presentation, indications for treatment, dissection revascularization success, and pseudoaneurysm obliteration evaluated by imaging, and to review available pertinent literature. METHODS: We retrospectively reviewed all cases of high cervical and skull base dissections treated with a PED at our institution. Patient clinical characteristics, presentation, procedural and follow-up imaging, and clinical course were analyzed to evaluate for procedure complications, dissection revascularization success, pseudoaneurysm obliteration, and clinical outcome. RESULTS: This is a retrospective case series including 11 patients with 13 carotid dissections treated in our center. There were nine traumatic and four spontaneous dissections. The most common presentation was cerebrovascular accident/transient ischemic attack (CVA/TIA; 5 patients) and headache/face pain (4 patients). Eleven dissections were associated with pseudoaneurysms. Three patients failed medical management with anticoagulation, although flow-limiting stenosis was the main indication for endovascular intervention. Up to three PEDs per vessel were deployed. Angioplasty was used in 10 cases. Complete revascularization (<10% residual stenosis) was achieved in 91% of vessels and 50% of pseudoaneurysms were completely or near completely obliterated immediately after PED(s) deployment. Proximal iatrogenic dissection was the only intraoperative complication. Follow-up imaging was available for nine treated vessels and demonstrated patent PEDs without significant in-stent stenosis up to 9 months after intervention. 75% of pseudoaneurysms were completely obliterated at follow-up. One PED partially collapsed but had no neurological consequences. There were no new CVA/TIAs. CONCLUSIONS: Our initial experience with treatment of high cervical and skull base dissections with the PED appears to show that this technique may be a safe and viable treatment option. However, long-term results are needed to fully evaluate the efficacy of such treatment.

Mechanical thrombectomy for pediatric stroke arising from an atrial myxoma: case report.

Children experiencing severe neurological deficit due to acute ischemic stroke may benefit from endovascular intervention. The authors describe the use of mechanical thrombectomy in the treatment of embolic occlusion secondary to an atrial myxoma in a pediatric patient. This case involved an 11-year-old boy with a history notable for Raynaud syndrome and a distal extremity rash who presented to the emergency department with dense hemiparesis secondary to thromboembolic occlusion of the M1 segment of the middle cerebral artery. Following mechanical thrombectomy, the patient's pediatric National Institutes of Health Stroke Scale score improved from a 16 to a 7. In the setting of acute pediatric stroke due to atrial myxoma emboli, mechanical thrombectomy may be a first-line therapy.

Giant cell reparative granuloma of the pediatric cranium: case report and review of the literature.

PURPOSE: Giant cell reparative granulomas are rare bone tumors. Although benign, these tumors are locally destructive and can be highly vascular. They seldom occur in the cranial vault. We describe a multidisciplinary approach to a case of giant cell reparative granuloma of the cranium in a 3-year-old patient. CASE REPORT: A 3-year-old girl female referred to the pediatric neurosurgery department for evaluation of a retro-auricular mass. She had a history of recurrent otitis media with two subsequent courses of antibiotics without resolution. CT imaging revealed an expansive lesion located in the right mastoid region. Open surgical biopsy revealed a hemorrhagic tumor consistent with a giant cell reparative granuloma. Angiography identified a hypervascular tumor blush that was supplied by the occipital artery. Preoperative transcatheter embolization was performed followed by a multidisciplinary surgical resection and reconstruction. Blood loss was minimal, and the patient recovered well after surgery. CONCLUSION: Preoperative endovascular embolization and a multidisciplinary intraoperative approach with primary resection and cranial vault reconstruction is an effective approach to hypervascular giant cell reparative granulomas.

An unusual case of pediatric bow hunter's stroke.

BACKGROUND: Bow Hunter's syndrome/stroke is defined as symptomatic, vertebrobasilar insufficiency provoked by physiologic head rotation. It is a diagnostically challenging cause of posterior circulation stroke in children. While there have been prior reports of this rare disorder, we describe an exceptional case of pediatric Bow Hunter's stroke resulting from a near complete occlusion the right vertebral artery (VA) secondary to an anomalous spur emanating from the right occipital condyle. Surgical and endovascular options and approaches are also detailed herein. CASE DESCRIPTION: A 16-year-old male presented with multiple posterior circulation ischemic strokes. A dynamic computerized tomography angiogram performed with the patient's head in a rotated position revealed a near complete occlusion of the V3 segment of the right VA from a bone spur arising from his occipital condyle. The spur caused a focal dissection of the distal right VA with associated thrombus. He was initially managed with a cervical collar, antiplatelet therapy with aspirin 81 mg and anticoagulation with coumadin (INR goal 2-3) for 3 months. Despite the management plan, he had a subsequent thromboembolic event and a right VA sacrifice with coil embolization was then performed. At the 3-month follow-up, the patient was doing well with no reports of any subsequent strokes. CONCLUSION: We report the first reported pediatric case of Bow Hunter's stroke due to dynamic right VA occlusion from an occipital condylar bone spur. The vascular compression from this spur led to a right VA dissection and thrombus formation and ultimately caused multiple posterior circulation thromboembolic strokes. Endovascular treatment options including vessel sacrifice should be considered in cases that have failed maximal medical management.

Factors associated with aspirin resistance in patients premedicated with aspirin and clopidogrel for endovascular neurosurgery.

OBJECTIVE: Antiplatelet therapy is critical to endovascular neurosurgical procedures. Some patients are aspirin-resistant nonresponders. We reviewed our endovascular neurosurgery patients who were premedicated with aspirin and clopidogrel and identified nonresponders to aspirin. Factors associated with aspirin resistance were determined. METHODS: Consecutive endovascular neurosurgery patients were identified who were treated by the senior author (BLH) from December 2006 to October 2007 and who were premedicated with aspirin (325 mg) and clopidogrel (75 mg) for 7 days before the procedure. We retrospectively reviewed values from the platelet function analyzer-100 test (Dade-Behring, Deerfield, IL) from 1 day before the procedures. The following factors were evaluated for association with aspirin drug resistance: age, sex, body mass index, and smoking history; patients with hypertension, diabetes, coronary artery disease/ peripheral vascular disease, or hypercholesterolemia; disease pathology (aneurysm, intracranial stenosis, or extracranial stenosis); patients taking statins, beta-blockers, angiotensin-converting enzyme inhibitors/angiotensin receptor blockers, or antidepressants; and white blood cell count, hemoglobin, hematocrit, and platelet levels. A stepwise logistic model selection was used to select important factors and their interactions. RESULTS: Eighty-one consecutive patients with the following interventions were included in the study: 35 aneurysm coilings (43%), 21 stent-assisted aneurysm coilings (26%), 13 carotid stent and angioplasties (16%), 7 intracranial stents and angioplasties (9%), and 5 extracranial vertebral artery stents and angioplasties (6%). Seventeen patients (21%) were nonresponders to aspirin. After model selection, the only factor associated with aspirin resistance was not taking an angiotensin-converting enzyme inhibitor or angiotensin receptor blocker (P = 0.0348; odds ratio, 0.214; 95% confidence interval, 0.051-0.896). CONCLUSION: Twenty-one percent of patients premedicated with aspirin and clopidogrel dual therapy for 7 days before endovascular neurosurgical procedures were nonresponders to aspirin. Patients not taking an angiotensin-converting enzyme inhibitor or angiotensin receptor blocker may be at higher risk for aspirin drug resistance.

Frameless, pinless stereotactic neurosurgery in children.

OBJECT: Frameless neuronavigation has been established as a useful adjunct to intracranial surgery; however, the procedure is limited in young children by the need for rigid skull fixation with pins. Pin fixation is difficult and hazardous for patients younger than 2 years of age. Minor risks have been associated with pin fixation in older patients also, including scalp laceration, skull fracture, and epidural hematoma. METHODS: The authors adapted a pinless head fixation system, consisting of a beanbag device, for use with frameless neuronavigation. This system was used to perform intracranial neurosurgical procedures in nine patients. CONCLUSIONS: This pinless, frameless method provides a new option for children who are unable to sustain rigid head fixation. It is also an alternative to rigid pin fixation for patients of any age.