Faculty Bibliography

Aneurysms of the anterior cerebral artery (ACA) located distal to the anterior communicating artery complex (ACOM) remain challenging to treat with surgical clip reconstruction as well as with endovascular coil-embolization strategies. We have treated five complex geometry distal ACA aneurysms with endoluminal reconstruction using the Pipeline Embolization Device (PED). Two aneurysms were of the dysplastic fusiform type. Three aneurysms were of complex saccular configuration. Three aneurysms were treated electively at the outset with PED. One patient had previously undergone aborted clip reconstruction, and one was treated for recurrent aneurysm growth after coil embolization. The mean diameter of the ACA in this cohort was 1.96mm proximal to the aneurysm and 1.79mm distal to the aneurysmal segment. A single PED of 2.5mm inner diameter was the sole treatment in four cases. Two PEDs, telescopically overlapped across the aneurysm, were used in the remaining case. All devices were deployed successfully. No parent artery occlusion or stenosis was observed. In all cases an associated branch vessel arising from the vicinity of the aneurysm or incorporated into its neck was covered by the endoluminal construct. At follow-up angiography, robust antegrade flow was maintained in the jailed branch. One patient experienced asymptomatic, delayed occlusion of the jailed branch. Complete aneurysm occlusion was seen in all patients. We confirm that PED can be deployed in parent vessels smaller than 2mm diameter, and that endoluminal reconstruction with the PED may be a safe and effective treatment alternative for selected distal ACA aneurysms.

OBJECTIVE The long-term effectiveness of endovascular treatment of large and giant wide-neck aneurysms using traditional endovascular techniques has been disappointing, with high recanalization and re-treatment rates. Flow diversion with the Pipeline Embolization Device (PED) has been recently used as a stand-alone therapy for complex aneurysms, showing significant improvement in effectiveness while demonstrating a similar safety profile to stent-supported coil treatment. However, relatively little is known about its long-term safety and effectiveness. Here the authors report on the 3-year safety and effectiveness of flow diversion with the PED in a prospective cohort of patients with large and giant internal carotid artery aneurysms enrolled in the Pipeline for Uncoilable or Failed Aneurysms (PUFS) trial. METHODS The PUFS trial is a prospective study of 107 patients with 109 aneurysms treated with the PED. Primary effectiveness and safety end points were demonstrated based on independently monitored 180-day clinical and angiographic data. Patients were enrolled in a long-term follow-up protocol including 1-, 3-, and 5-year clinical and imaging follow-up. In this paper, the authors report the midstudy (3-year) effectiveness and safety data. RESULTS At 3 years posttreatment, 74 subjects with 76 aneurysms underwent catheter angiography as required per protocol. Overall, complete angiographic aneurysm occlusion was observed in 71 of these 76 aneurysms (93.4% cure rate). Five aneurysms were re-treated, using either coils or additional PEDs, for failure to occlude, and 3 of these 5 were cured by the 3-year follow-up. Angiographic cure with one or two treatments of Pipeline embolization alone was therefore achieved in 92.1%. No recanalization of a previously completely occluded aneurysm was noted on the 3-year angiograms. There were 3 (2.6%) delayed device- or aneurysm-related serious adverse events, none of which led to permanent neurological sequelae. No major or minor late-onset hemorrhagic or ischemic cerebrovascular events or neurological deaths were observed in the 6-month through 3-year posttreatment period. Among 103 surviving patients, 85 underwent functional outcome assessment in which modified Rankin Scale scores of 0-1 were demonstrated in 80 subjects. CONCLUSIONS Pipeline embolization is safe and effective in the treatment of complex large and giant aneurysms of the intracranial internal carotid artery. Unlike more traditional endovascular treatments, flow diversion results in progressive vascular remodeling that leads to complete aneurysm obliteration over longer-term follow-up without delayed aneurysm recanalization and/or growth. Clinical trial registration no.: NCT00777088 ( clinicaltrials.gov ).

OBJECTIVE A detailed analysis was performed of anterior circulation aneurysms treated with a Pipeline Embolization Device (PED) that did not progress to complete occlusion by 1-year follow-up. Angiography was performed with the purpose of identifying specific factors potentially responsible for these failed outcomes. METHODS From among the first 100 patients with anterior circulation aneurysms, 92 underwent 1-year follow-up angiography and were individually studied through review of their pre- and postembolization studies. RESULTS Nineteen aneurysms (21%) remained unoccluded at 12 months. Independent predictors of treatment failure, identified by logistic regression analysis, were found to be fusiform aneurysm morphology, decreasing dome-to-neck ratio, and the presence of a preexisting laser-cut stent. Further examination of individual cases identified several common mechanisms-device malapposition, inadequate coverage of the aneurysm neck with persistent exchange across the device, and the incorporation of a branch vessel into the aneurysm fundus-potentially contributing to failed treatment in these settings. CONCLUSIONS Attention to specific features of the aneurysm and device construct can frequently identify cases predisposed to treatment failure and suggest strategies to maximize favorable outcomes.

Introduction: Femoral artery closure devices allow for earlier mobilization and improved comfort for patients after vascular access. The Mynx device (Cardinal Health, Inc.) is an extravascular closure device that deploys a polyethylene glycol plug, and is maximally labeled for 6/7 French sheath closure. Here we report our experience using the device to close 8F sheaths in patients post endovascular treatment of ischemic stroke. Methods: We performed a retrospective analysis of all stroke cases where the 6/7F Mynx device was used with 8F sheaths. Operating room flowsheets, physician and nursing notes up to 2 weeks post angiography were reviewed and data on deployment and complications were analyzed. Results: 87 consecutive stroke embolectomy cases at an academic center were reviewed from 2014 through 2016. 8F short sheaths were utilized in 23 patients, and all 23 were closed with 6/7F Mynx device. Average compression time following Mynx deployment was 18 minutes. The mean patient age was 70.7 years. The average BMI was 27. Ten patients (38%) had received IV tPA; 6 patients were on anticoagulation(27%); and 2 patients had coagulapathies. Two (8%) patients had documented groin bruising post Mynx; both resolved spontaneously. No patients had loss of ipsilateral distal pulses post mynx; in 1 patient, distal pulses changed from palpable to dopplerable. No patient had significant pain or swelling at the site. There were no groin site infections. Conclusions: Off-Label use of 6/7F Mynx for 8F closure is safe and efficacious, and was not associated with an increased complication rate in our small cohort

Foreign material emboli following cerebral, cardiac, and peripheral catheterizations have been reported since the mid-1990s. Catheter coatings have been frequently implicated. The most recent surge of interest in this phenomenon within the neurointerventional community is associated with procedures using flow-diversion devices for the treatment of cerebral aneurysms. Following coil-supported Pipeline embolization in 4 cases and stent-supported coiling in 1, 5 patients developed multiple subcentimeter enhancing lesions, usually with surrounding edema and variable magnetic susceptibility in the vascular territories of the treated aneurysms. Conventional angiography findings were unrevealing. Laboratory work-up showed mild CSF protein elevation with no leukocytosis. Brain biopsy in 2 cases revealed granulomatous angiitis encasing foreign material, identical in stain appearance to a polyvinylpyrrolidone catheter coating. Corticosteroid administration typically produced clinical improvement. A heterogeneous radiographic and clinical course was noted, with rise and fall in the number of enhancing lesions in 2 patients and persistence in others. The etiology may be related to widespread adoption of increasingly sophisticated catheterization techniques.

OBJECT Neuroophthalmological morbidity is commonly associated with large and giant cavernous and supraclinoid internal carotid artery (ICA) aneurysms. The authors sought to evaluate the neuroophthalmological outcomes after treatment of these aneurysms with the Pipeline Embolization Device (PED). METHODS The Pipeline for Uncoilable or Failed Aneurysms (PUFS) trial was an international, multicenter prospective trial evaluating the safety and efficacy of the PED. All patients underwent complete neuroophthalmological examinations both before the PED procedure and at a 6-month follow-up. All examinations were performed for the purpose of this study and according to study criteria. RESULTS In total, 108 patients were treated in the PUFS trial, 98 of whom had complete neuroophthalmological follow-up. Of the patients with complete follow-up, 39 (40%) presented with a neuroophthalmological baseline deficit that was presumed to be attributable to the aneurysm, and patients with these baseline deficits had significantly larger aneurysms. In 25 of these patients (64%), the baseline deficit showed at least some improvement 6 months after PED treatment, whereas in 1 patient (2.6%), the deficits only worsened. In 5 patients (5%), new deficits had developed at the 6-month follow-up, while in another 6 patients (6%), deficits that were not originally assumed to be related to the aneurysm had improved by that time. A history of diabetes was associated with failure of the baseline deficits to improve after the treatment. The aneurysm maximum diameter was significantly larger in patients with a new deficit or a worse baseline deficit at 6 months postprocedure. CONCLUSIONS Patients treated with the PED for large and giant ICA aneurysms had excellent neuroophthalmological outcomes 6 months after the procedure, with deficits improving in most of the patients, very few deficits worsening, and few new deficits developing.

BACKGROUND AND PURPOSE: Treatment options for nonsaccular posterior cerebral artery aneurysms include a range of surgical and endovascular reconstructive and deconstructive methods. However, no truly satisfactory treatment option is available to date for lesions arising from the P1 and P2 segments. The purpose of the present case series is to investigate both the efficacy and safety of the Pipeline Embolization Device in treating these challenging aneurysms. MATERIALS AND METHODS: We present a series of 6 consecutive patients who underwent endoluminal reconstruction with the Pipeline Embolization Device for nonsaccular P1 or P2 segment aneurysms between January 2009 and June 2013. RESULTS: Aneurysm location included the P1 segment in 2 patients and the P2 segment in 4 patients. Mean aneurysm diameter was 23 mm (range, 5-44 mm). Mean length of the arterial segment involved was 10 mm (range, 6-19 mm). Clinical presentation included mass effect in 4 patients and perforator stroke and subacute aneurysmal subarachnoid hemorrhage in 1 patient each. Endovascular reconstruction was performed by using 1 Pipeline Embolization Device in 5 patients and 2 overlapping Pipeline Embolization Devices in the remaining patient. Angiographic aneurysm occlusion was immediate in 1 patient, within 6 months in 4 patients, and within 1 year in the remaining patient. Index symptoms resolved in 4 patients and stabilized in the remaining 2. No new permanent neurologic sequelae and no aneurysm recurrence were recorded during the mean follow-up period of 613 days (range, 540-725 days). CONCLUSIONS: Endovascular reconstruction with the Pipeline Embolization Device for nonsaccular aneurysms arising from the P1 and P2 segments compares favorably with historical treatment options in terms of occlusion rate, margin of safety, and neurologic outcome.

BACKGROUND AND PURPOSE: Endoluminal reconstruction with the Pipeline Embolization Device is an effective treatment option for select intracranial aneurysms. However, concerns for the patency of eloquent branch arteries covered by the Pipeline Embolization Device have been raised. We aimed to examine the patency of the anterior choroidal artery and clinical sequelae after ICA aneurysm treatment. MATERIALS AND METHODS: We prospectively analyzed all patients among our first 157 patients with ICA aneurysms treated by the Pipeline Embolization Device who required placement of at least 1 device across the ostium of the anterior choroidal artery. The primary outcome measure was angiographic patency of the anterior choroidal artery at last follow-up. Age, sex, type of aneurysm, neurologic examination data, number of Pipeline Embolization Devices used, relationship of the anterior choroidal artery to the aneurysm, and completeness of aneurysm occlusion on follow-up angiograms were also analyzed. RESULTS: Twenty-nine aneurysms requiring placement of at least 1 Pipeline Embolization Device (median = 1, range = 1-3) across the anterior choroidal artery ostium were identified. At angiographic follow-up (mean = 15.1 months; range = 12-39 months), the anterior choroidal artery remained patent, with antegrade flow in 28/29 aneurysms (96.5%), while 24/29 (82.7%) of the target aneurysms were angiographically occluded by 1-year follow-up angiography. Anterior choroidal artery occlusion, with retrograde reconstitution of the vessel, was noted in a single case. A significant correlation between the origin of the anterior choroidal artery from the aneurysm dome and failure of the aneurysms to occlude following treatment was found. CONCLUSIONS: After placement of 36 Pipeline Embolization Devices across 29 anterior choroidal arteries (median = 1 device, range = 1-3 devices), 1 of 29 anterior choroidal arteries was found occluded on angiographic follow-up. The vessel occlusion did not result in persistent clinical sequelae. Coverage of the anterior choroidal artery origin with the Pipeline Embolization Device, hence, may be considered reasonably safe when deemed necessary for aneurysm treatment.

Endovascular embolization is typically reserved as an adjuvant therapy in the management of cerebral arteriovenous malformations (AVMs), either for preoperative devascularization or preradiosurgical volume reduction. Curative embolization plays a limited role in AVM treatment but several studies have shown that it is possible, especially with later-generation liquid embolic agents. Given the complexity of AVM anatomy and the recent controversies over the role of any intervention in AVM management, it is critical that the cerebrovascular community better define the indications of each treatment modality to provide quality AVM management. In this review, the authors evaluate the role of curative AVM embolization. Important considerations in the feasibility of curative AVM embolization include whether it can be performed reliably and safely, and whether it is a durable cure. Studies over the past 20 years have begun to define the anatomical factors that are amenable to complete endovascular occlusion, including size, feeding artery anatomy, AVM morphology, and endovascular accessibility. More recent studies have shown that highly selected patients with AVMs can be treated with curative intent, leading to occlusion rates as high as 100% of such prospectively identified lesions with minimal morbidity. Advances in endovascular technology and techniques that support the efficacy and safety of curative embolization are discussed, as is the importance of superselective diagnostic angiography. Finally, the durability of curative embolization is analyzed. Overall, while still unproven, endovascular embolization has the potential to be a safe, effective, and durable curative treatment for select AVMs, broadening the armamentarium with which one can treat this disease.