Craig Kilburg

Pipeline embolization device for the treatment of vertebral artery aneurysms: the fate of covered branch vessels

Introduction Preliminary studies suggest that flow-diverting stents may be suitable for the treatment of aneurysms of the posterior circulation. The safety and efficacy of using flow-diverting stents for vertebral artery (VA) aneurysms is not well defined. Objective To examine the fate of covering the posterior inferior cerebellar artery (PICA) in patients undergoing placement of a flow-diverting stent for VA aneurysm. Methods Consecutive patients who underwent placement of a Pipeline Embolization Device (PED) for treatment of an aneurysm of the V4 segment of the VA between April 2012 and June 2015 at our institution were retrospectively evaluated. Angiograms were reviewed to determine the patency of the PICA when the vessel origin was covered by the PED. Results 11 patients with VA aneurysms who underwent treatment with the PED were identified. In each case the device covered the origin of the PICA. Follow-up angiography in eight patients demonstrated thrombosis of the aneurysm with patency of the PICA. Conclusions Flow-diverting stents can be used for the treatment of VA aneurysms. When appropriately sized to the vessel wall and positioned in the VA, the device may cover the origin of the PICA without impairing flow through the branching artery.

Pipeline Embolization Device with or without Adjunctive Coil Embolization: Analysis of Complications from the IntrePED Registry

SUMMARY: Flow diversion to treat cerebral aneurysms has revolutionized neurointerventional surgery. Because the addition of coils potentially increases the time and complexity of endovascular procedures, we sought to determine whether adjunctive coil use is associated with an increase in complications. Patients in the International Retrospective Study of Pipeline Embolization Device registry were divided into those treated with the Pipeline Embolization Device alone (n = 689 patients; n = 797 aneurysms; mean aneurysm size, 10.3 ± 7.6 mm) versus those treated with the Pipeline Embolization Device and concurrent coil embolization (n = 104 patients; n = 109 aneurysms; mean aneurysm size, 13.6 ± 7.8 mm). Patient demographics and aneurysm characteristics were examined. Rates of neurologic morbidity and mortality were compared between groups. The Pipeline Embolization Device with versus without coiling required a significantly longer procedure time (135.8 ± 63.9 versus 96.7 ± 46.2 min; P < .0001) and resulted in higher neurological morbidity (12.5% versus 7.8%; P = .13). These data suggest that either strategy represents an acceptable risk profile in the treatment of complex cerebral aneurysms and warrants further investigation.

Advanced imaging in acute ischemic stroke

The evaluation and management of acute ischemic stroke has primarily relied on the use of conventional CT and MRI techniques as well as lumen imaging sequences such as CT angiography (CTA) and MR angiography (MRA). Several newer or less-established imaging modalities, including vessel wall MRI, transcranial Doppler ultrasonography, and 4D CTA and MRA, are being developed to complement conventional CT and MRI techniques. Vessel wall MRI provides high-resolution analysis of both extracranial and intracranial vasculature to help identify previously occult lesions or characteristics of lesions that may portend a worse natural history. Transcranial Doppler ultrasonography can be used in the acute setting as a minimally invasive way of identifying large vessel occlusions or monitoring the response to stroke treatment. It can also be used to assist in the workup for cryptogenic stroke or to diagnose a patent foramen ovale. Four-dimensional CTA and MRA provide a less invasive alternative to digital subtraction angiography to determine the extent of the clot burden and the degree of collateral blood flow in large vessel occlusions. Along with technological advances, these new imaging modalities are improving the diagnosis, workup, and management of acute ischemic stroke- roles that will continue to expand in the future.

Patterns and Clinical Impact of Angiographically Visible Distal Emboli During Thrombectomy With Solitaire for Acute Ischemic Stroke.

BACKGROUND Revascularization rates with stent retrievers after acute ischemic stroke are 69% to 86%, but favorable clinical outcomes occur in just 43% to 58% of cases. New distal emboli may negatively impact clinical outcomes. OBJECTIVE To determine the prevalence and angiographic pattern of distal emboli associated with mechanical thrombectomy using the Solitaire Flow Restoration device and evaluate their correlation with clinical outcome. METHODS We retrospectively reviewed the cerebral angiography of all patients with acute ischemic stroke who underwent mechanical thrombectomy with the use of the Solitaire FR device from 2012 to 2013. Angiographic microcatheter runs prior to Solitaire deployment and after thrombectomy were compared to identify new distal filling defects. Clinical outcome was assessed at discharge and after 90 days. RESULTS Successful revascularization using the Solitaire device occurred in 36 of 39 patients (92%). Three distinct patterns were identified: new distal emboli in the same vascular territory (n = 3), new distal emboli in a new vascular territory (n = 3), and distal emboli that resolved after proximal revascularization (n = 7). Thirteen patients had distal emboli before and after Solitaire runs, and 13 showed no evidence of distal emboli. Favorable outcome (modified Rankin scores 0-2) was seen in 54% of all patients and 83% of patients with new distal emboli; thus, there was no correlation between new emboli and unfavorable clinical outcome (P = .67). CONCLUSION We report an incidence rate of at least 15% of new emboli associated with use of the Solitaire device during thrombectomy in our series. Filling defects after Solitaire use were not associated with poor outcomes at discharge or 90-day follow-up.

Novel use of flow diversion for the treatment of aneurysms associated with arteriovenous malformations

The use of flow-diverting stents for intracranial aneurysms has become more prevalent, and flow diverters are now routinely used beyond their initial scope of approval at the proximal internal carotid artery. Although flow diversion for the treatment of cerebral aneurysms is becoming more commonplace, there have been no reports of its use to treat flow-related cerebral aneurysms associated with arteriovenous malformations (AVMs). The authors report the cases of 2 patients whose AVM-associated aneurysms were managed with flow diversion. A 40-year-old woman presented with a history of headaches that led to the identification of an unruptured Spetzler-Martin Grade V, right parietooccipital AVM associated with 3 aneurysms of the ipsilateral internal carotid artery. Initial attempts at balloon-assisted coil embolization of the aneurysms were unsuccessful. The patient underwent placement of a flow-diverting stent across the diseased vessel; a 6-month follow-up angiogram demonstrated complete occlusion of the aneurysms. In the second case, a 57-year-old man presented with new-onset seizures, and an unruptured Spetzler-Martin Grade V, right frontal AVM associated with an irregular, wide-necked anterior communicating artery aneurysm was identified. The patient underwent placement of a flow-diverting stent, and complete occlusion of the aneurysm was observed on a 7-month follow-up angiogram. These 2 cases illustrate the potential for use of flow diversion as a treatment strategy for feeding artery aneurysms associated with AVMs. Because of the need for dual antiplatelet medications after flow diversion in this patient population, however, this strategy should be used judiciously.

Complications in Endovascular Neurosurgery: Critical Analysis and Classification.

BACKGROUND Precisely defining complications, which are used to measure overall quality, is necessary for critical review of delivery of care and quality improvement in endovascular neurosurgery, which lacks common definitions for complications. Furthermore, in endovascular interventions, events that may be labeled complications may not always negatively affect outcome. Our objective is to provide precise definitions for quality evaluation within endovascular neurosurgery. Thus, we propose an endovascular-specific classification system of complications based on our own patient series. METHODS This single-center review included all patients who had endovascular interventions from September 2013 to August 2015. Complication types were analyzed, and a descriptive analysis was undertaken to calculate the incidence of complications overall and in each category. RESULTS Two hundred and seventy-five endovascular interventions were performed in 245 patients (65% female; mean age, 55 years). Forty complications occurred in 39 patients (15%), most commonly during treatment of intracranial aneurysms (24/40). Mechanical complications (eg, device deployment, catheter, or closure device failure) occurred in 8/40, technical complications (eg, failure to deploy flow diverter, unintended embolization, air emboli, retroperitoneal hemorrhage, dissection) in 11/40, judgment errors (eg, patient or equipment selection) in 9/40, and critical events (eg, groin hematoma, hemorrhagic or thromboembolic complications) in 12/40 patients. Only 12/40 complications (30%) resulted in new neurologic deficits, vessel injury requiring surgery, or blood transfusion. CONCLUSIONS We propose an endovascular-specific classification system of complications with 4 categories: mechanical, technical, judgment errors, and critical events. This system provides a framework for future studies and quality control in endovascular neurosurgery.

Moderate Sedation for Pipeline Embolization of Posterior Circulation Disease: Technical Note from a Single Center

OBJECTIVE Flow diversion has been an important addition to endovascular neurosurgery, but its use in the posterior circulation remains controversial. Our goal is to describe the safety and efficacy of moderate sedation during flow diversion for posterior circulation lesions (aneurysms or dissecting pseudoaneurysms). METHODS The authors retrospectively reviewed the medical records of all patients who underwent placement of a Pipeline embolization device for a posterior circulation lesion using moderate sedation at a single institution from August 2012 through November 2017. Clinical data and outcomes were evaluated. RESULTS Fifteen consecutive patients were identified: 8 female, 7 male (mean age 52.2 ± 16.3 years, range 15-81). Eleven lesions were located in the vertebral artery, 1 in the posterior inferior cerebellar artery, 2 in the posterior cerebral artery, and 1 in the basilar artery. All patients underwent flow diversion with Pipeline embolization devices. One patient experienced an acute occlusion of the basilar artery during the procedure that required revascularization. Mean fluoroscopy time was 35.6 ± 16.5 minutes (range 15.5-75). Mean follow-up time was 12.7 ± 8.8 months (range 3-36). No patient had new neurologic deficits in the perioperative or postoperative period. Conversion to general anesthesia was not required in any case. CONCLUSIONS Moderate sedation is safe and feasible in patients undergoing flow diversion for posterior circulation lesions. In addition, its use may allow for more rapid identification of procedural complications, facilitating emergent treatment and decreasing procedure-related morbidity.

Postoperative Posterior Ischemic Optic Neuropathy After Left Far-Lateral Craniectomy for Resection of Craniocervical Meningioma

BACKGROUND Postoperative posterior ischemic optic neuropathy (PION) is a rare cause of postoperative vision loss, most often seen when surgical patients are placed in the prone position for a prolonged period of time. We report a case of bilateral PION after far-lateral craniectomy in the lateral position. CASE DESCRIPTION A 36-year-old man presented with a history of right extremity numbness, weakness, and muscle atrophy, and a craniocervical meningioma was diagnosed. Surgery in the lateral position lasted 9 hours, 52 minutes; the patient had 2 L of blood loss. On postoperative day 1, the patient had bilateral vision loss, which prompted further work-up. Diffusion-weighted imaging of the orbits demonstrated restricted diffusion within the bilateral optic nerves. The clinical presentation of painless vision loss after surgery with these imaging findings led to a diagnosis of PION. At the time of discharge, he had not recovered any visual function. CONCLUSIONS This case suggests that PION can occur in the lateral position where there is no direct pressure on the orbits. PION is often not discussed as a potential complication during the preoperative consent process. This case suggests it may be prudent to discuss PION in similar neurosurgical cases. Intraoperative blood transfusion should be considered in prolonged surgeries in the lateral position, where slow blood loss over a long period could be a contributing factor to development of PION.

Intravenous acetaminophen for postoperative supratentorial craniotomy pain: a prospective, randomized, double-blinded, placebo-controlled trial

In BriefThe authors designed a randomized, double-blinded, placebo-controlled trial to evaluate intravenous acetaminophen as a scheduled adjunct with our standardized craniotomy pain control regimen. No statistically significant effect was found in narcotic consumption at 24 or 48 hours after surgery. At 24 but not 48 hours, patients treated with intravenous acetaminophen did report significantly lower pain scores than patients given the placebo. These data provide only modest support for using intravenous acetaminophen to improve postoperative craniotomy pain.

Arterial dissection following the use of remote aspiration thrombectomy

Remote aspiration thrombectomy using a balloon guide catheter for acute carotid artery occlusion has been proposed as a safe and effective technique. We present a case of iatrogenic arterial dissection of the distal cervical segment in a patient with proximal vessel occlusion who underwent attempted revascularization using this strategy. A 57-year-old male patient presented with computed tomography (CT) angiogram evidence of a left carotid terminus and M1 segment occlusion. The patient was taken emergently for mechanical thrombectomy. Remote aspiration thrombectomy was attempted twice using manual aspiration through a balloon guide catheter in the common carotid artery; however, this resulted in minimal recanalization of the carotid terminus and a new iatrogenic dissection within the internal carotid artery (ICA) just proximal to the skull base. Despite multiple additional attempts at mechanical thrombectomy, only limited recanalization of the ICA terminus and anterior cerebral artery distribution was achieved, with no significant flow past the M1 segment. After the procedure, a large ischemic territory within the left middle cerebral artery distribution consistent with the continued M1 segment occlusion was apparent on CT. The patient died on the poststroke day 6. Although remote aspiration thrombectomy for thromboemboli in this location has potential benefits, it should be used cautiously given the potential risk of injury to the proximal vasculature.