Jorge L. Eller

The Pipeline embolization device for treatment of intracranial aneurysms

Flow diversion is a new endovascular technique developed for treatment of intracranial aneurysms. It is based on stent-induced modification of blood flow within and around an aneurysm inflow zone, leading to gradual intra-aneurysmal thrombosis and subsequent atrophy, while preserving flow into the parent vessel and perforating branches. Flow-diversion technique is well-suited for the treatment of large, giant, wide-necked, and fusiform intracranial aneurysms because it does not rely on endosaccular packing with coils but rather on the strategy of placing a stent across the aneurysm “neck” or across the diseased segment of a vessel in case of a fusiform aneurysm. Over time, neointimal endothelium covers the flow diverter such that it becomes incorporated into the parent vessel wall and occludes the aneurysm from the circulation, effectively repairing the diseased parent vessel segment. This report describes in detail the Pipeline embolization device (ev3-Covidien, Irvine, California, USA), its mechanism of action and deployment technique, and reviews the pertinent literature regarding safety, efficacy and potential risks and complications associated with the use of this flow diverter.

Submaximal angioplasty for symptomatic intracranial atherosclerosis: a prospective Phase I study.

OBJECTIVE Intracranial atherosclerotic disease (ICAD) accounts for approximately 10% of ischemic strokes. The recent Stenting and Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis (SAMMPRIS) study demonstrated a high incidence of perioperative complications (15%) for treatment of ICAD with stenting. Although the incidence of stroke was lower in the medical arm, recurrent stroke was found in 12% of patients despite aggressive medical management, suggesting that intervention may remain a viable option for ICAD if perioperative risk is minimized. Angioplasty without stenting represents an alternative and understudied revascularization treatment for ICAD. Submaximal angioplasty limits the risks of thromboembolism, vessel perforation, and reperfusion hemorrhage that were frequently reported with stenting in the SAMMPRIS trial. The authors conducted a prospective Phase I trial designed to assess the safety of submaximal angioplasty in patients with symptomatic ICAD. METHODS This study was approved by the local institutional review board. Demographic and clinical data were prospectively collected. Angioplasty was performed with a balloon undersized to approximately 50%-70% of the nondiseased vessel diameter in patients with symptomatic ICAD who had angiographically significant stenosis of ≥ 70%. The primary outcome measure was the incidence of periprocedural complications (combined rate of death, stroke, and hemorrhage occurring within 30 days and at 1 year). RESULTS Among the 65 patients with symptomatic ICAD who were screened, 24 had significant angiographic stenosis that met the inclusion criteria of this study. The mean age was 64.08 years (median 65 years; SD ± 11.24 years), most were men (62.5%), and most were white (66.67%). Many patients had concomitants of vascular disease, including hypertension (95.8%), hyperlipidemia (70.83%), smoking history (54.1%), and diabetes mellitus (50.0%). Coronary artery disease (41.66%) and previous stroke or transient ischemic attack (45.83%) were frequently present. Most patients (75%) had anterior circulation stenosis. The mean preprocedure stenosis was 80.16% (median 80%, range 70%-95%). Submaximal angioplasty was performed in patients who met the inclusion criteria, with a mean postangioplasty stenosis rate of 54.62% (median 55.5%, range 31%-78%). Rates of ischemic stroke in the territory of the treated artery were 0% within 30 days and 5.55% (in the only patient who presented with recurrent stroke) at 1 year. The mortality and hemorrhage rates in this series were 0%. CONCLUSIONS This study demonstrates the safety of the submaximal angioplasty technique, with no permanent periprocedural complications in 24 treated patients.

Primary stenting for acute ischemic stroke using the Enterprise vascular reconstruction device: early results

Objective Primary stenting for acute ischemic stroke (AIS) using the Wingspan stent delivery system has been reported. Major technical limitations in that study were difficulties in delivering the device and a few cases in which the Enterprise vascular reconstruction device (stent) was used as a bailout procedure. The Enterprise, which has relatively less radial force and more flexibility than other intracranial stents, is an ideal device for revascularization as it is easily delivered through tortuous intracranial vessels. We tested the safety and effectiveness of this stent as the primary revascularization device for AIS in an FDA-approved investigational device exemption prospective cohort study. Methods Twenty patients presenting with AIS due to confirmed intracranial large vessel occlusion within 8 h of onset of stroke symptoms were treated with the Enterprise as the primary revascularization device. The primary outcome was recanalization to Thrombolysis In Myocardial Infarction (TIMI) flow of ≥2. Perioperative safety was measured by major complication incidence within 30 days of stent revascularization. A secondary measure of outcome was 30-day modified Rankin Scale (mRS) score. Results Recanalization to TIMI 2 (n=6) or 3 (n=12) flow was achieved in 18 patients (90% revascularization rate). Three major complications were noted (15%) including one myocardial infarction, one symptomatic intracranial hemorrhage and one ischemic stroke in a distribution other than the qualifying vessel. Good outcome (mRS ≤2) was obtained in 10 patients (50%). Conclusions In this prospective study the Enterprise stent was found to be a safe and effective revascularization tool in the setting of AIS.

Combined use of covered stent and flow diversion to seal iatrogenic carotid injury with vessel preservation during transsphenoidal endoscopic resection of clival tumor.

Background: Transsphenoidal tumor resection can lead to internal carotid artery (ICA) injury. Vascular disruption is often treated with emergent vessel deconstruction, incurring complications in a subset of patients with poor collateral circulation and resulting in minor and major ischemic strokes. Methods: We attempted a novel approach combining a covered stent graft (Jostent) and two flow diverter stents [Pipeline embolization devices (PEDs)] to treat active extravasation from a disrupted right ICA that was the result of a transsphenoidal surgery complication. This disruption occurred during clival tumor surgery and required immediate sphenoidal sinus packing. Emergent angiography revealed continued petrous carotid artery extravasation, warranting emergent vessel repair or deconstruction for treatment. To preserve the vessel, we utilized a covered Jostent. Due to tortuosity and lack of optimal wall apposition, there was reduced, yet persistent extravasation from an endoleak after Jostent deployment that failed to resolve despite multiple angioplasties. Therefore, we used PEDs to divert the flow. Results: Flow diversion relieved the extravasation. The patient remained neurologically intact post-procedure. Conclusions: This case demonstrates successful combined use of a covered stent and flow diverters to treat acute vascular injury resulting from transsphenoidal surgery. However, concerns remain, including the requirement of dual antiplatelet agents increasing postoperative bleeding risks, stent-related thromboembolic events, and delayed in-stent restenosis rates.

Carotid artery stenting outcomes: do they correlate with antiplatelet response assays?

Objective Limited data exist regarding the use of antiplatelet response assays during neuroendovascular intervention. We report outcomes after carotid artery stenting (CAS) based on aspirin and P2Y12 assays. Methods We retrospectively identified patients who had aspirin and P2Y12 assays at the time of stenting. Aspirin (325 mg) and clopidogrel (75 mg) were started 7–10 days pre-intervention. If not possible, aspirin (650 mg) and clopidogrel (600 mg) loading doses were given pre-intervention. Assays were checked on postoperative day 0/1. Outcomes included neurological ischemic sequela at 30 days, 1 and 2 years, as well as 30 day death/hemorrhage/myocardial infarction. Results 449 patients were included. Mean P2Y12 reaction unit (PRU) values were higher in patients with an ipsilateral ischemic event (stroke/transient ischemic attack (TIA)) or stroke (alone) at 1 and 2 years than in patients with no events: ischemic event versus no event at 1 year, 252 vs 202 (p=0.008); stroke versus no stroke at 1 year, 252 versus 203(p=0.029); ischemic event versus no event at 2 years, 244 vs 203 (p=0.047); stroke versus no stroke at 2 years, 243 versus 203 (p=0.082). Ischemic event free survival (stroke/TIA, p=0.0268) and overall survival (p=0.0291) post-CAS were longer in patients with PRU ≤198 compared with an initial threshold of PRU ≤237. Mean PRU values were higher in patients who died from all causes at 30 days than in survivors (p=0.031). No correlation was found between lower PRU values and hemorrhage. Aspirin reaction units did not correlate with outcome. Conclusions PRU ≤198 may be associated with a lower incidence of ischemic neurological sequela and death post-CAS. Prospective studies are needed to validate the relationship between antiplatelet assays and outcomes post-CAS.

Utility of intravascular ultrasound in intracranial and extracranial neurointerventions: experience at University at Buffalo Neurosurgery–Millard Fillmore Gates Circle Hospital

Intravascular ultrasound (IVUS) generates high-resolution cross-sectional images and sagittal reconstructions of the vessel wall and lumen. As a result, this imaging modality can provide accurate measurements of the degree of vessel stenosis, allow the detection of intraluminal thrombus, and analyze the plaque composition. The IVUS modality is widely used in interventional cardiology, and its use in neurointerventions has gradually increased. With case examples, the authors illustrate the utility of IVUS as an adjunct to conventional angiography for a wide range of intracranial and extracranial neurointerventions.

Transfemoral endovascular treatment of atherosclerotic stenotic lesions of the left common carotid artery ostium: case series and review of the literature

Objective Endovascular treatment of atherosclerotic stenosis of the left common carotid artery ostium (LCCAO) represents a technical challenge. Unlike stenting of other supra-aortic trunk lesions, LCCAO stenting is not able to be performed from a retrograde approach through the brachial artery. Stenting may be performed via a retrograde approach with a carotid artery cut-down or with total endovascular technique via a transfemoral approach. A consecutive case series is presented to demonstrate the feasibility and safety of the endovascular transfemoral LCCAO stenting technique. Methods Our prospectively maintained database of elective neuroendovascular procedures was searched for cases of LCCAO angioplasty and stenting for atherosclerotic stenosis performed between January 2003 and April 2012. Cases identified were isolated and analyzed for clinical and anatomic data. The primary outcome of interest was the incidence of periprocedural (30-day) neurological or cardiopulmonary complications. Results Fourteen patients were treated with a transfemoral approach (mean arterial stenosis 72%; symptomatic lesions 86%). Six (43%) had tandem stenosis of the proximal left internal carotid artery. In these cases, embolic protection was used. Stent revascularization was a technical success in all 14 patients, resulting in <20% residual stenosis in each. One intraprocedural complication (transient ischemic attack) was noted in a patient with symptomatic stenosis. One additional patient was identified who was treated with retrograde stenting due to bilateral leg amputations and no femoral access, with no periprocedural complication. Conclusions In our experience, transfemoral stenting of stenotic LCCAO lesions is feasible and no permanent neurological or cardiopulmonary sequelae occurred in 14 patients treated with this technique.

Advances in endovascular approaches to cerebral aneurysms.

Abstract Recent advancements in all phases of endovascular aneurysm treatment, including medical therapy, diagnostics, devices, and implants, abound. Advancements in endovascular technologies and techniques have enabled treatment of a wide variety of intracranial aneurysms. In this article, technical advances in endovascular treatment of cerebral aneurysms are discussed, with an effort to incorporate a clinically relevant perspective. Advancements in diagnostic tools, medical therapy, and implants are reviewed and discussed.Recent advancements in all phases of endovascular aneurysm treatment, including medical therapy, diagnostics, devices, and implants, abound. Advancements in endovascular technologies and techniques have enabled treatment of a wide variety of intracranial aneurysms. In this article, technical advances in endovascular treatment of cerebral aneurysms are discussed, with an effort to incorporate a clinically relevant perspective. Advancements in diagnostic tools, medical therapy, and implants are reviewed and discussed.

Endovascular Treatment of Acute Ischemic Stroke

Endovascular stroke therapy has revolutionized the management of patients with acute ischemic stroke in the last decade and has facilitated the development of sophisticated stroke imaging techniques and a multitude of thrombectomy devices. This article reviews the scientific basis and current evidence available to support endovascular revascularization and provides brief technical details of the various methods of endovascular thrombectomy with case examples.

Cerebrovascular neurosurgery in evolution: the endovascular paradigm.

Endovascular technique represents an important, minimally invasive approach to treating cerebrovascular disease. In this article, we discuss the origins of endovascular neurosurgery as a discipline in the context of important technical milestones, evidence-based medicine, and future cerebrovascular neurosurgical training. Cerebrovascular neurosurgery has seen a steady, convergent evolution toward the surgeon capable of seamless incorporation of open and endovascular approaches to any complex vascular disease affecting the central nervous system. Neurosurgery must assume the leadership role in the multidisciplinary neurovascular team.Endovascular technique represents an important, minimally invasive approach to treating cerebrovascular disease. In this article, we discuss the origins of endovascular neurosurgery as a discipline in the context of important technical milestones, evidence-based medicine, and future cerebrovascular neurosurgical training. Cerebrovascular neurosurgery has seen a steady, convergent evolution toward the surgeon capable of seamless incorporation of open and endovascular approaches to any complex vascular disease affecting the central nervous system. Neurosurgery must assume the leadership role in the multidisciplinary neurovascular team.