J Lozano

ARTS (Aspiration-Retriever Technique for Stroke): Initial clinical experience.

Background A new generation of highly navigable large-bore aspiration catheters and retriever devices for intracranial mechanical thrombectomy has markedly improved recanalization rates, time and clinical outcomes. We report collected clinical data utilizing a new technique based on combined large lumen aspiration catheter and partially resheathed stent retriever (ARTS: Aspiration (catheter)–(stent) Retriever Technique for Stroke). This technique is applied, especially in presence of bulky/rubbery emboli, when resistance is felt while retracting the stent retriever; at that point the entire assembly is locked and removed in-toto under continuous aspiration with additional flow arrest. Methods A retrospective data analysis was performed to identify patients with large cerebral artery acute ischemic stroke treated with ARTS. The study was conducted between August 2013 and February 2015 at a single high volume stroke center. Procedural and clinical data were captured for analysis. Results Forty-two patients (median age 66 years) met inclusion criteria for this study. The ARTS was successful in achieving Thrombolysis in Cerebral Infarction (TICI) ≥2b revascularization in 97.6% of cases (TICI 2b = 18 patients, TICI 3 = 23 patients). Patients’ median National Institutes of Health Stroke Scale score at admission was 18 (6–40). A 3-month follow-up modified Rankin Scale value of 0–2 was achieved in 65.7% of the successfully treated patients (average 2.4). Two patients (4.8%) developed symptomatic intraparenchymal hemorrhages. Six procedure unrelated deaths were observed. Conclusions We found that ARTS is a fast, safe and effective method for endovascular recanalization of large vessel occlusions presenting within the context of acute ischemic stroke.

Endovascular reconstruction of unruptured intradural vertebral artery dissecting aneurysms with the Pipeline embolization device

Background Dissecting aneurysms of the vertebral artery (VA) are difficult to treat using current surgical and endovascular techniques. Objective To analyze retrospectively the efficacy and safety of flow diverters in the treatment of dissecting aneurysms of the vertebral artery. Methods We identified six patients with six unruptured VA dissecting aneurysms either arising from the V4 or V3–V4 junction that were treated with the Pipeline embolization device (PED) at our institution between July 2012 and February 2015. Among other parameters, technical feasibility of the procedure, procedure-related complications, angiographic results, and clinical outcome were evaluated. Results PED placement was achieved in all cases and immediate angiography follow-up demonstrated intra-aneurysmal contrast stasis with parent artery preservation. A temporary episode of dysarthria was noted in one patient. Major procedure-related complications were not observed. The 6-month follow-up (n=6) demonstrated complete/near-complete aneurysm obliteration in five patients and partial obliteration in one. At the 1-year follow-up (n=5) stable complete aneurysm occlusion was seen in two patients. Two cases showed progression from near complete occlusion and partial occlusion at 6 months to complete occlusion and near complete occlusion. One cases showed unchanged near complete occlusion. No aneurysmal bleeding, in-stent stenosis or thromboembolic complication was seen. National Institutes of Health Stroke Scale and modified Rankin scale scores remained unchanged from admission to discharge. Conclusions Our preliminary experience with the use of PED for the treatment of intradural VA dissecting aneurysms shows promising short-term results, making this technique a feasible and safe treatment option in patients suitable for this approach. However, long-term and larger cohort studies are needed to validate these results.

Two-year single-center experience with the ‘Baby Trevo’ stent retriever for mechanical thrombectomy in acute ischemic stroke

Objective To evaluate the safety and efficacy of the ‘Baby Trevo’ (Trevo XP ProVue 3×20 mm Retriever) stent retriever for large vessel occlusions (LVOs) in acute ischemic stroke (AIS). Materials and methods We retrospectively analyzed our stroke database and included all patients treated with the Baby Trevo for distal LVOs in AIS. Patient gender, mean age, vascular risk factors, National Institutes of Health Stroke Scale (NIHSS) score at presentation, and modified Rankin Scale (mRS) score at baseline and 90-day follow-up were documented. Reperfusion rates for the vessels treated were recorded using the Thrombolysis in Cerebral Infarction (TICI) classification. Occurrence of vasospasm and new or evolving infarcts in the treated vascular territory was documented. Results Thirty-five subjects with a mean NIHSS score of 18 were included. The Baby Trevo device was used in 38 branches of the anterior and posterior circulations. TICI 2b/3 blood flow was restored after one single pass in 20/38 (52.6%) and after two or three passes in 11 vessels. The remaining vessels required either more than three passes, showed less than a TICI 2b/3 reperfusion (n=3), or demonstrated failure to retrieve the clot (n=4). TICI 2b/3 reperfusion was achieved in 30 patients (85.7%). No vessel injuries, rupture, or significant vasospasm were seen. Overall, a mRS score of ≤2 was seen in 56.5% of the subjects successfully treated with the Baby Trevo at 90 days and in 81.3% of surviving patients; seven patients died (20%). Conclusions Our preliminary data suggest that the ‘Baby Trevo’ achieves a high recanalization rate without any significant risk. Larger cohort studies are needed to validate the clinical benefit.

Onyx embolization in distal dissecting posterior inferior cerebellar artery aneurysms

Background Dissecting aneurysms located along the distal segments of the posterior inferior cerebellar artery (PICA) are extremely rare, accounting for only 0.5–0.7% of all intracranial aneurysms. Treatment of these aneurysms is challenging, both surgically and endovascularly. We present our preliminary experience and clinical data utilizing Onyx as an embolization agent in the treatment of these lesions with proximal parent artery preservation. Methods 7 consecutive ruptured peripheral PICA aneurysms, in 7 patients, were treated with superselective Onyx embolization at our institutions. According to the anatomical classification of Lister et al, these aneurysms were located in the lateral medullary segment (n=1), tonsillomedullary segment (n=1), and the telovelotonsillary segment (n=5) of the PICA. Technical feasibility, procedure related complications, angiographic results, follow-up diagnostic imaging, and clinical outcome were evaluated. Results In all cases, endovascular treatment was successful, with complete occlusion of the aneurysm with proximal parent artery preservation at the final postprocedural angiogram. Procedure related complications were not observed. One patient with a poor clinical condition at admission died during the initial hospital stay due to extensive subarachnoid and intraventricular hemorrhage. No rebleeding or recanalization was noted during follow-up. Two patients had a residual moderate to severe disability at follow-up. Favorable outcomes, with no or mild disability, were observed in four of the surviving patients. Conclusions Angiographic, diagnostic imaging, and clinical results of our small series indicate that Onyx embolization of dissecting distal PICA aneurysms with parent artery preservation is an effective option with acceptable morbidity and mortality rate, in those cases in which surgical clipping or endovascular coiling of the aneurysmal sac is not suitable.

E-040 Five-year Single Center Experience of Intracranial Aneurysm Treatment with the PED in Patients of different Age Groups

Purpose To evaluate safety and efficacy of the pipeline embolization device (PED) in patients of different age groups and with incidentally found or recanalised (previously coiled or clipped) aneurysms. Materials and methods All patients with an incidentally found or recanalised aneurysm and treated with the PED at our institution between 2011 and 2016 were included. We then divided the patient cohort into three age groups representing young (Y, ≤45 years), middle age (M, 46- <65 years) and older (O, ≥65 years) individuals. Information on patient’s vascular risk factors, presenting symptoms and mRS on admission was collected. Follow-up imaging was evaluated for aneurysmal occlusion and the presence of intimal hyperplasia. Patient clinical outcome at discharge, 6 and 12 months was documented. Results We included 140 patients harboring 164 aneurysms with 20 patients in the young age group, 88 in the middle age and 32 in the older age group. Male to female ratio was approximately 1:4 overall and interestingly in all age groups as well. The majority of aneurysms were located in the anterior circulation (94.5%) and found incidentally (75%). Twenty-four aneurysms had been previously treated (12 ruptured and 12 unruptured). Smoking, hypertension and dyslipidemia were the most frequently encountered vascular risk factors in all age groups, with smoking being most common in the young, hypertension the most common in the middle age and hypertension/dyslipidemia the most common in the older age group. Median mRS on admission and discharge was 0 for all age groups. The median mRS remained 0 at 6 and 12 month follow-up. Overall mortality and morbidity rate was 2.1% (3/140, M = 2 and O = 1), Complete aneurysm occlusion at 6 and 12 months was seen in 77% (78/101) and 80% (52/65), respectively. Mild intimal hyperplasia was seen in 18 cases total (18%) with 2 cases in the young, 11 in the middle age and 5 in the older age group. Moderate and severe intimal hyperplasia was found in one case each (young and older age group). No retreatment was required. Nine aneurysms (Y = 3, M = 5 and O = 1) which demonstrated near complete occlusion at 6 months showed complete occlusion in 2 cases (M = 2) and stable near complete occlusion in the remaining 7 at the 12 month mark. For aneurysms demonstrating partial occlusion at 6 months (Y = 2, M = 5, O = 3), 12 months follow-up showed progression to complete or near complete occlusion in 1 case each (Y = 1 and M = 1) and stable partial occlusion in 3 cases (M = 3). Available 12 months follow-up for mild intimal hyperplasia detected at 6 months showed resolution in 4 cases (M = 1 and O = 3) and stable mild hyperplasia in 5 cases (Y = 1 and M = 4). One case of moderate intimal hyperplasia at 6 months (young age group) improved to mild hyperplasia at 12 months follow-up. Subanalysis of treatment outcome of incidentally found aneurysms compared to unruptured pretreated or ruptured pretreated aneurysms showed no difference of flow diverter performance between the different aneurysm groups or among the different patient age groups. Conclusion PED placement is feasible and safe in patients of different age groups and with incidental or recanalised aneurysms. Disclosures A. Kuhn: None. J. Lozano: None. K. de Macedo Rodrigues: None. F. Massari: None. A. Wakhloo: 1; C; NIH, Philips Healthcare, Wyss Institute. 2; C; Codman Neurovascular and Stryker Neurovascular. 3; C; Harvard Postgraduate Course, Miami Cardiovascular Institute. 4; C; InNeuroCo Inc, EpiEB and Pulsar Medical. D. Rex: None. M. Gounis: 1; C; NIH, Medtronic Neurovascular, Microvention/Terumo, Cerevasc LLC, Gentuity, Codman Neurovascular, Philips Healthcare, Stryker Neurovascular, Tay Sachs Foundation, and InNeuroCo Inc. 2; C; Codman Neurovascular and Stryker Neurovascular. 4; C; InNeuroCo Inc. M. Marosfoi: None. M. Perras: None. C. Brooks:None. M. Howk: None. A. Puri: 1; C; Stryker Neurovascular and Covidien. 2; C; Codman Neurovascular, Stryker Neurovascular and Covidien. 3; C; Miami Cardiovascular Institute. 4; C; InNeuroCo Inc.

E-043 Reversible Cerebral Vasoconstriction Syndrome: Non-invasive Imaging Findings and Angiographic Evaluation

Purpose Reversible Cerebral Vasoconstriction Syndrome (RCVS) is a transient disorder of cerebral arterial auto regulation that may have a non-specific clinical presentation, most typically initiating as an acute episode of severe (thunderclap) headache. The clinical scenario and the non-invasive imaging findings are similar to those seen in more common pathologies making it a challenging diagnosis if the entity is not a consideration in the initial evaluation. RCVS presentation and initial imaging findings may mimic a ruptured aneurysm, stroke, migraine and posterior reversible encephalopathy syndrome, among others. Our aim is to describe the entity of RCVS and demonstrate the common and uncommon imaging findings seen on CT, MRI, CT angiography, with emphasis on conventional digital subtraction arteriogram pre and post endovascular treatment. Approach/methods A multimodality pictorial review of cases from our institution is presented, including non-contrast head CT, CT angiogram, MRI, MR angiogram and conventional digital subtraction arteriogram (DSA). Diagnosis of RCVS was confirmed by imaging demonstration of reversibility of arterial constriction on follow-up imaging or after intra-arterial therapy. Findings/discussion We present indirect findings on non-invasive imaging, such as transient cerebral edema, convexal subarachnoid hemorrhage, intraparenchymal hemorrhage and cerebral. Direct signs of single or multivessel arterial vasoconstriction are seen on CTA, MRA and confirmed on DSA. Reversibility of the vasoconstriction is demonstrated after intra-arterial administration of calcium channel blocker. Conditions such as diffuse atherosclerotic arterial narrowing, vasculitis, posterior reversible encephalopathy, cerebral edema secondary to venous congestion and vasospasm secondary to aneurysmal subarachnoid hemorrhage were among the pathologies considered prior to a definitive diagnosis of RCVS. Summary/conclusion Familiarity with the imaging findings of RCVS is of critical importance to direct appropriate and timely clinical management. Atypical subarachnoid hemorrhage, unexplained cerebral edema and hemorrhage, as well as single or multivessel diffuse narrowing with a relatively normal appearing brain should raise suspicion of RCVS. Suspicion can be confirmed by demonstrating the reversibility of vasoconstrictions after intra-arterial administration of calcium channel blocker or at follow-up imaging.Abstract E-043 Figure 1 48-year old female presenting with severe headache and evidence of subarachnoid hemorrhage on head CT (not shown). No aneurysm or other causes for intracranial bleed was demonstrated on DSA. (A) Multiple segmentel areas of vasoconstrictions of the MCA and ACA branches are demonstrated. (B) There is significant improvement of the degree if vasoconstriction after intra-arterial administration of calcium channel blocker. Disclosures K. de Macedo Rodrigues: None. R. Hito: None. D. Takhtani: None. J. Lozano: None. A. Wakhloo: 1; C; NIH, Philips Healthcare, Wyss Institute. 2; C; Codman Neurovascular and Stryker Neurovascular. 4; C; co-founder of InNeuroCo Inc. and major stockholder; stocks in EpiEB and Pulsar Medical. 6; C; speaker: Harvard Postgraduate Course, Miami Cardiovascular Institute. A. Puri: 1; C; Stryker Neurovascular and Covidien. 2; C; Codman Neurovascular, Stryker Neurovascular and Covidien. 4; C; InNeuroCo Inc. 6; C; speaker: Miami Cardiovascular Institute.

E-070 Endovascular Techniques for Achievement of Better Flow Diverter Wall Apposition

Purpose Flow diverter malapposition as a technical complication with the use of the pipeline embolization device has been described and maybe is associated with delayed ischemic events or potentially delayed life-threatening aneurysm rupture. We describe our endovascular techniques for manipulation of flow diverters in order to achieve proper vessel wall apposition. Materials and methods We retrospectively analyzed our flow diverter database and included all patients in whom malapposition of the device was detected on follow-up angiography immediately after device deployment. We then evaluated feasibility and technical success of different endovascular approaches aimed to correct the inadequate vessel wall apposition. Successful endovascular techniques for manipulation of the device included use of wires, catheters and additional devices. Final confirmation of flow diverter wall apposition prior to completion of the intervention was performed using 3D multi-planar cone-beam CT reconstruction images. Results We identified 5 successful endovascular techniques for better flow diverter wall apposition: 1) Use of a wire with a J, pigtail or S-shaped tip passed through the device, 2) Manipulation with a microcatheter, which can be used to press the PED against the vessel wall, 3) Balloon angioplasty of the malapposed segment, 4) Manipulation with an intermediate catheter, which can be used at the proximal edge or within the flow diverter to push the PED against the vessel wall, 5) Placement of another flow diverter within the previously placed FD to better oppose the ends and 6) Placement of an open-cell stent in telescopic fashion across the malapposed portion of the PED (proximal or distal edge). The Neuroform stent with its high outward radial force is an excellent adjunct treatment option to anchor the malapposed flow diverter against the vessel wall while permitting perforator patency. Conclusion Flow diverter malapposition can be addressed successfully during the interventional procedure using a variety of techniques. This may prevent devastating delayed complications. Disclosures A. Kuhn: None. K. de Macedo Rodrigues: None. M. Gounis: 1; C; NIH, Medtronic Neurovascular, Microvention/Terumo, Cerevasc LLC, Gentuity, Codman Neurovascular, Philips Healthcare, Stryker Neurovascular, Tay Sachs Foundation, and InNeuroCo Inc. 2; C; Codman Neurovascular and Stryker Neurovascular. 4; C; InNeuroCo Inc. P. Kan: 2; C; Stryker Neurovascular, Covidien, and MicroVention. M. Marosfoi: None. J. Lozano: None. M. Perras: None. C. Brooks: None. M. Howk: None. D. Rex: None. F. Massari: None. A. Wakhloo: 1; C; NIH, Philips Healthcare, Wyss Institute. 2; C; Codman Neurovascular and Stryker Neurovascular. 3; C; Harvard Postgraduate Course, Miami Cardiovascular Institute. 4; C; InNeuroCo Inc, EpiEB and Pulsar Medical. A. Puri: 1; C; Stryker Neurovascular and Covidien. 2; C; Codman Neurovascular, Stryker Neurovascular and Covidien. 3; C; Miami Cardiovascular Institute. 4; C; InNeuroCo Inc.

E-020 Between a Rock and a Hard Place: The Use of Self-expanding Stents for the Endovascular Treatment of Acute Ischemic Stroke due to Recalcitrant Emergency Large Vessel Occlusion in the Era of Stent-retrievers: Single-center Experience and Early Results

Objective The efficacy of stent-retrievers in achieving recanalization in the setting of acute ischemic stroke (AIS) secondary to an emergency large vessel occlusion (ELVO) has now been conclusively proven in several randomized clinical trials. However, in a small subset of these patients recanalization may not be achieved by means of mechanical thrombectomy with stent-retrievers and/or thromboaspiration with large bore catheters. In selected cases of this type of recalcitrant occlusion, acute intracranial stenting may be safe and effective as a last and final effort to achieve flow restoration and improve recanalization rates with good clinical outcomes (Modified Ranking Scale (mRS) ≤2). Methods Retrospective analysis of 7 patients who underwent endovascular treatment of ELVO between January 2012 and April 2016 at a single tertiary care center with acute intracranial stenting for a vessel occlusion recalcitrant to recanalization by means of standard mechanical thrombectomy and/or thromboaspiration techniques. Results Six males and a female with median baseline National Institutes of Health Stroke Scale (NIHSS) score of 20 (range 18–29) were included in this study. Three occlusive lesions were located from the internal carotid artery (ICA) terminus to the M1, 2 lesions were distal M1 occlusions, 1 lesion was a distal M1 occlusion that spanned the superior and inferior M2 divisions, and 1 lesion was at the distal basilar extending to the bilateral P1 segments. The median number of attempted yet unsuccessful mechanical thrombectomies before considering acute intracranial stenting was 4. One procedure included balloon angioplasty prior to stenting, two procedures included mechanical thromboaspiration in addition to mechanical thrombectomy with stent-retrievers, and one of the procedures included intra-arterial TPA and thromboaspiration in between stent-retriever attempts. Two cases required Y-stenting due to recalcitrant clot burden at the bifurcation of a large vessel (MCA bifurcation into superior and inferior M2 divisions, and distal basilar artery into bilateral P1 segments; mRS at 30 days was 0 and 1, respectively). The average time from last seen well to recanalization with acute intracranial stenting was 317 min +187 min. Recanalization rates were AOL 2 in 85% (6/7) and AOL 3 in 15% of cases (1/7). Reperfusion rates were TICI 3 in one case, TICI 2 B in 4 and TICI 2 A in 2 cases. Supraselective intra-arterial eptafibatide was used either before or immediately after stenting in 42% of cases (3/7); daily aspirin after stenting was used in all cases (7/7); and a combination of aspirin and clopidogrel was used in 71% of cases (5/7). There were two deaths: One as a result of hemorrhagic transformation of the ischemic stroke with subsequent malignant edema and the second one due to progression of stroke and withdrawal of care at the request of the family. Modified Rankin Scale mRS ≤2 at 30 days was achieved in 42% of the cases (3/7). Conclusion Initial results suggest that acute intracranial stenting may be beneficial in a subset of patients who present with an ELVO and who have failed recanalization by means of mechanical thrombectomy with stent-retrievers and/or thromboaspiration with large bore intracranial catheters. Disclosures J. Lozano: None. M. Howk: None. A. Kuhn: None. F. Massari: None. K. de Macedo Rodrigues: None. C. Brooks: None. M. Perras: None. M. Gounis: 1; C; NIH, Medtronic Neurovascular, Microvention/Terumo, Cerevasc LLC, Gentuity, Codman Neurovascular, Phillips Healthcare, Stryker Neurovascular, Tay Sachs Foundation, InNeuroCo Inc. 2; C; Codman Neurovascular, Stryker Neurovascular. 4; C; InNeuroCo Inc. D. Rex: None. A. Wakhloo: 1; C; NIH, Phillips Healthcare, Wyss Institute. 2; C; Codman Neurovascular, Stryker Neurovascular. 3; C; Harvard Postgraduate Course. 4; C; InNeuroCo Inc., EpiEb, Pulsar Medical. A. Puri: 1; C; Stryker Neurovascular, Covidien. 2; C; Codman Neurovascular, Stryker Neurovascular, Covidien. 3; C; Miami Cardiovascular Institute. 4; C; InNeuroCo Inc.

E-091 Treatment of Aneurysms of the Pericallosal Artery with the Pipeline Embolization Device

Background/objective Pericallosal artery aneurysm treatment is challenging using traditional endovascular techniques due to the small caliber of the parent vessel and distal access. Wide neck and bifurcation aneurysms in this location require manipulation with 2 catheters for balloon assisted or stent assisted coil embolization with increased friction and limited margin for error. We demonstrate the feasibility, efficacy and safety of endovascular treatment of pericallosal artery aneurysm using flow diversion technology. Methods We performed a retrospective review of our institutional database from July 2013 through July 2015. Five subjects with a pericallosal artery aneurysm that was treated with the Pipeline embolization device (PED) were identified. We evaluated for technical feasibility, presence of procedural complication, angiographic results, and clinical outcome. Results Successful placement of a single PED across the neck of the aneurysm was achieved in all cases. No procedure-related complications were encountered. A 6 month follow-up angiogram was available for 4 patients and a 12 month follow-up angiogram was available for 2 patients. Four out of 5 patients had complete aneurysm occlusion demonstrated, 3 of them were demonstrated at the 6 month follow-up and 1 at 12 month follow-up. The subject for which occlusion was demonstrated at the 12 month follow-up did not have a 6 month angiogram available for review. One patient had persistent aneurysm filling at 6 month, with a 50–60% decrease in aneurysm size. There were 2 cases of narrowing of at the origin of an artery that had been coved by the PED, without flow limitation or clinical consequences. There was no evidence of in-stent stenosis or intimal hyperplasia. No thromboembolic or hemorrhagic complication was seen. Modified Rankin scale scores remained unchanged from baseline. Conclusions Our preliminary results support the use of flow diverter stent for treatment of aneurysms of the pericallosal artery with high rate of aneurysm occlusion, without evidence of increased procedural complication or short-term morbidity. A long-term and larger cohort study is desirable to validate our results. Disclosures K. de Macedo Rodrigues: None. A. Kühn: None. T. Tamura: None. G. Dabus: None. P. Kan: 2; C; PK is a consultant for Stryker Neurovascular, Covidien, and MicroVention. M. Marosfoi: None. J. Lozano: None. M. Howk: None. M. Perras: None. C. Brooks: None. D. Rex: None. F. Massari: None. M. Gounis: 1; C; NIH, Medtronic Neurovascular, Microvention/Terumo, Cerevasc LLC, Gentuity, Codman Neurovascular, Philips Healthcare, Stryker Neurovascular, Tay Sachs Foundation, and InNeuroCo Inc. 2; C; Codman Neurovascular and Stryker Neurovascular. 4; C; InNeuroCo Inc. A. Wakhloo: 1; C; NIH, Philips Healthcare, Wyss Institute. 2; C; Codman Neurovascular and Stryker Neurovascular. 4; C; co-founder of InNeuroCo Inc. and major stockholder; stocks in EpiEB and Pulsar Medical. 6; C; speaker: Harvard Postgraduate Course, Miami Cardiovascular Institute. A. Puri: 1; C; Stryker Neurovascular and Covidien. 2; C; Codman Neurovascular, Stryker Neurovascular and Covidien. 4; C; InNeuroCo Inc. 6; C; speaker: Miami Cardiovascular Institute.