Collin M. Torok

Open and endovascular treatment of spinal dural arteriovenous fistulas: a 10-year experience

OBJECTIVE Vascular malformations of the spine represent rare clinical entities with profound neurological implications. Previously reported studies on management strategies for spinal dural arteriovenous fistulas (sDAVFs) appeared before the advent of modern liquid embolic agents. Authors of the present study review their institutional experience with endovascularly and surgically treated sDAVFs. METHODS The authors performed a retrospective, observational, single-center case series on sDAVFs treated with endovascular embolization, microsurgical occlusion, or both between 2004 and 2013. The mode, efficacy, and clinical effect of treatment were evaluated. RESULTS Forty-seven patients with spinal arteriovenous malformations were evaluated using spinal angiography, which demonstrated 34 Type I sDAVFs (thoracic 20, lumbar 12, and cervical 2). Twenty-nine of the patients (85%) were male, and the median patient age was 63.3 years. Twenty patients underwent primary endovascular embolization (16 Onyx, 4 N-butyl cyanoacrylate [NBCA]), and 14 underwent primary surgical clipping. At a mean follow-up of 36 weeks, according to angiography or MR angiography, 5 patients treated with endovascular embolization demonstrated persistent arteriovenous shunting, whereas none of the surgically treated patients showed lesion persistence (p = 0.0237). Thirty patients (88%) experienced some resolution of their presenting symptoms (embolization 17 [85%], surgery 13 [93%], p = 1.00). CONCLUSIONS Microsurgical occlusion remains the most definitive treatment modality for sDAVFs, though modern endovascular techniques remain a viable option for the initial treatment of anatomically amenable lesions. Treatment of these lesions usually results in some clinical improvement.

A direct aspiration first-pass technique vs stentriever thrombectomy in emergent large vessel intracranial occlusions

OBJECTIVE Endovascular thrombectomy in patients with acute ischemic stroke caused by occlusion of the proximal anterior circulation arteries is superior to standard medical therapy. Stentriever thrombectomy with or without aspiration assistance was the predominant technique used in the 5 randomized controlled trials that demonstrated the superiority of endovascular thrombectomy. Other studies have highlighted the efficacy of a direct aspiration first-pass technique (ADAPT). METHODS To compare the angiographic and clinical outcomes of ADAPT versus stentriever thrombectomy in patients with emergent large vessel occlusions (ELVO) of the anterior intracranial circulation, the records of 134 patients who were treated between June 2012 and October 2015 were reviewed. RESULTS Within this cohort, 117 patients were eligible for evaluation. ADAPT was used in 47 patients, 20 (42.5%) of whom required rescue stentriever thrombectomy, and primary stentriever thrombectomy was performed in 70 patients. Patients in the ADAPT group were slightly younger than those in the stentriever group (63.5 vs 69.4 years; p = 0.04); however, there were no differences in the other baseline clinical or radiographic factors. Procedural time (54.0 vs 77.1 minutes; p < 0.01) and time to a Thrombolysis in Cerebral Infarction (TICI) scale score of 2b/3 recanalization (294.3 vs 346.7 minutes; p < 0.01) were significantly lower in patients undergoing ADAPT versus stentriever thrombectomy. The rates of TICI 2b/3 recanalization were similar between the ADAPT and stentriever groups (82.9% vs 71.4%; p = 0.19). There were no differences in the rates of symptomatic intracranial hemorrhage or procedural complications. The rates of good functional outcome (modified Rankin Scale Score 0-2) at 90 days were similar between the ADAPT and stentriever groups (48.9% vs 41.4%; p = 0.45), even when accounting for the subset of patients in the ADAPT group who required rescue stentriever thrombectomy. CONCLUSIONS The present study demonstrates that ADAPT and primary stentriever thrombectomy for acute ischemic stroke due to ELVO are equivalent with respect to the rates of TICI 2b/3 recanalization and 90-day mRS scores. Given the reduced procedural time and time to TICI 2b/3 recanalization with similar functional outcomes, an initial attempt at recanalization with ADAPT may be warranted prior to stentriever thrombectomy.

110 Noninferiority of a Direct Aspiration First-Pass Technique vs Stent Retriever Thrombectomy in Emergent Large-Vessel Intracranial Occlusions.

INTRODUCTION:Endovascular thrombectomy in patients with acute ischemic stroke caused by occlusion of proximal anterior circulation arteries has emerged as superior to standard medical therapy. While stent retriever thrombectomy with or without aspiration assistance was utilized in the 5 randomized c

Validation of the Modified Raymond–Roy classification for intracranial aneurysms treated with coil embolization

Background The Raymond–Roy Occlusion Classification (RROC) qualitatively assesses intracranial aneurysm occlusion following endovascular coil embolization. The Modified Raymond–Roy Classification (MRRC) was developed as a refinement of this classification scheme, and dichotomizes RROC III occlusions into IIIa (opacification within the interstices of the coil mass) and IIIb (opacification between the coil mass and aneurysm wall) closures. Methods To demonstrate in an external cohort the predictive accuracy of the MRRC, the records of 326 patients with 345 intracranial aneurysms treated with endovascular coil embolization from January 2007 to December 2013 were retrospectively analyzed. Results Within this cohort, 84 (24.3%) and 83 aneurysms (24.1%) had MRRC IIIa and IIIb closures, respectively, during initial coil embolization. Progression to complete occlusion was more likely with IIIa than IIIb closures (53.6% vs 19.2%, p≤0.01), while recanalization was more likely with IIIb than IIIa closures (65.1% vs 27.4%, p<0.01). Kaplan–Meier estimates demonstrated a significant difference in the test of equality for progression to complete occlusion (p=0.02) and recurrence (p<0.01) between class IIIa and IIIb distributions. For the entire cohort, male gender (p<0.01), ruptured aneurysm (p=0.04), intraluminal thrombus (p<0.01), and MRRC IIIb closure (p<0.01) were identified as predictors of recanalization. For aneurysms with an initial RROC III occlusion, MRRC IIIa closure was found to be an independent predictor of progression to complete occlusion (p=0.02). Conclusions This study confirms that the MRRC enhances the predictive accuracy of the RROC.

Transarterial venous sinus occlusion of dural arteriovenous fistulas using ONYX.

Purpose The purpose of this article is to present a case series of transarterial venous sinus occlusion for dural arteriovenous fistulas (DAVFs) of the transverse and sigmoid sinuses. Materials and methods From 2006 to 2012, 11 patients with DAVF of the transverse and sigmoid sinuses were treated with transarterial closure of the affected venous sinus using ethylene vinyl alcohol copolymer (ONYX). The consecutive retrospective cohort included six female and five male patients with an age range of 30–79. Patients presented with stroke, intracranial hemorrhage, seizure, headache, focal neurologic deficit or cognitive change. Lesions were categorized as Cognard II a + b (n = 5) or Cognard II b (n = 6). Four of this latter group consisted of isolated sinus segments. Selection criteria for dural sinus occlusion included direct multi-hole fistulas involving a broad surface in length or circumference of the sinus wall. External carotid artery (ECA) branches were directly embolized when considered safe. High-risk arterial supply from ICA, PICA, AICA or ECA cranial nerve branches were closed via retrograde approach during sinus occlusion. Results DAVF closure was accomplished in all 11 patients with a total of 17 embolization procedures using ONYX. High-risk arterial collaterals were closed via artery-artery or artery-sinus-artery embolization. The vein of Labbe was spared in the four cases with initial antegrade flow. No neurologic complications occurred, and DAVF closures were durable on three-month angiography. Conclusion Transarterial closure of the transverse and sigmoid sinuses.

Rapid growth of an infectious intracranial aneurysm with catastrophic intracranial hemorrhage.

Infectious intracranial aneurysms are rare vascular lesions that classically occur in patients with infective endocarditis. We present a 49-year-old man with altered mental status and headache with rapid growth and rupture of an infectious intracranial aneurysm with catastrophic intracranial hemorrhage, and review issues related to open neurosurgical and endovascular interventions.

Surgical management of superior petrosal sinus dural arteriovenous fistulae with dominant internal carotid artery supply

Background While technological advances have improved the efficacy of endovascular techniques for tentorial dural arteriovenous fistulae (DAVF), superior petrosal sinus (SPS) DAVF with dominant internal carotid artery (ICA) supply frequently require surgical intervention to achieve a definitive cure. Methods To compare the angiographic and clinical outcomes of endovascular and surgical interventions in patients with SPS DAVF, the records of all patients with tentorial DAVF from August 2010 to November 2015 were reviewed. Results Within this cohort, eight patients with nine SPS DAVF were eligible for evaluation. Five DAVF were initially treated with endovascular embolization, while four underwent surgical occlusion without embolization. Of the SPS DAVF treated with embolization, two (40%) remained occluded on follow-up, while the remaining three (60%) persisted/recurred and required surgical intervention for definitive closure. Of the four SPS DAVF treated with primary surgical occlusion, all four (100%) remained closed on follow-up. In addition, of the three SPS DAVF that persisted/recurred following embolization and required subsequent surgical closure, all three (100%) remained occluded on follow-up. Two (100%) SPS DAVF that were successfully treated with embolization had major or minor external carotid artery supply, while the three (100%) persistent lesions had major ICA supply via the meningohypophyseal trunk (MHT). Three (75%) of the four SPS DAVF treated with primary surgical occlusion had dominant MHT supply. Conclusion Complete endovascular closure of SPS DAVF with dominant ICA supply via the MHT may be difficult to achieve, while upfront surgical intervention is associated with a high rate of complete occlusion.

Early experience with the Penumbra SMART coil in the endovascular treatment of intracranial aneurysms: Safety and efficacy

Background Penumbra SMART coils differ from traditional microcoils used for endovascular coil embolization of intracranial aneurysms (IAs) in that they (1) become progressively softer from their distal to proximal end, rather than being of uniform stiffness, (2) have a tight conformational structure, and (3) have a more robust stretch-resistance platform. These properties aid in preventing microcatheter prolapse and coil herniation during coil deployment and in filling small pockets of the aneurysm sac. Objective/Methods To determine the safety and efficacy of this device, the records of 17 consecutive patients with IAs treated with SMART coils were retrospectively analyzed. Results Thirteen female and four male patients were identified. Eleven patients presented with subarachnoid hemorrhage, four had recurrent aneurysms, and two had incidentally discovered aneurysms. Twelve aneurysms (two of which were recurrent) were treated with stand-alone coiling, three were treated with stent-assisted coiling, and two with flow diversion with adjuvant coiling. Microcatheter prolapse occurred in one case of a recurrent aneurysm, due to mechanical limitations imposed by a stent placed during prior coiling. Raymond-Roy Occlusion Classification (RROC) I or II occlusion was achieved in 12 aneurysms, including all 10 undergoing primary stand-alone coiling. Of the five RROC III occlusions, two were expected given treatment with flow diversion, while the other three occurred in complex, recurrent aneurysms. One patient suffered a thromboembolic complication of unclear clinical significance. Conclusions The Penumbra SMART coil is a safe and effective device for the endovascular treatment of IAs. Follow-up studies are required to establish long-term results.

Flow Diversion for the Treatment of an Unruptured Paraclinoid Carotid Artery Aneurysm

Treatment of paraclinoid aneurysms can be performed with surgical clipping, coil embolization, or flow diversion. Flow diversion has emerged as a preferred treatment modality in many scenarios because of its low complication rate, high cure rate, and minimally invasive nature. In this case, a female in her mid50s underwent flow diversion for treatment of an unruptured paraclinoid segment aneurysm. She began taking aspirin and Plavix (Bristol Myers Squibb, New York, New York) 7 days before the procedure and underwent deployment of the stent without difficulty or adverse event. This case highlights the step-bystep technique of Pipeline Flex device deployment (Covidien/ev3 Neurovascular, Medtronic, Minneapolis, Minnesota) for the treatment of a complex proximal carotid artery aneurysm.

P-019 Role of collateral circulation in branch vessel occlusion from flow diversion

Introduction/Purpose Flow diversion with the Pipeline Embolization Device (PED) often necessitates covering branch vessels. A number of studies suggest a low rate of branch vessel occlusion with only rare clinical complications from these occlusions. We and others hypothesize that branch vessel occlusion is generally clinically silent due to collateral circulation from ECA to ICA anastomoses (e.g. in the case of the ophthalmic artery) or via the circle of Willis. Materials and Methods We reviewed a consecutive retrospective cohort of 64 patients from 2011–2016, who had branch vessel coverage associated with aneurysm flow diversion. Immediate post-treatment angiography and interval follow-up angiography was evaluated for branch vessel opacification. Branch vessels demonstrated either normal, slow, or absent contrast opacification. Collateral circulation was assessed for all branch vessels with slow or absent flow when selective angiography was available. Results In our cohort, we identified 106 branch vessels covered by the PED construct in 64 patients. These were primarily anterior circulation branches (99 of 106) and of those, most were ophthalmic arteries (56 of 99). Slow flow was seen in 11 of 106 branches (10%), only 1 of which progressed on follow up to full occlusion. Angiographic occlusion was seen in 11 vessels (10%). Seven patients had new or worsening neurologic deficits, two of which were associated with stent thrombosis. Three patients had new visual deficits although the covered ophthalmic artery remained patent; two patients had new or worsening 6th nerve palsy related to mass effect from coils and/or the thrombosed aneurysm. The majority of branch vessels with altered flow (slow or absent) had angiographic evidence of collateral circulation (15 of 22, 68%). Altered branch vessel flow was not associated with new or worsening neurologic deficit. In the subset of branch vessels with altered flow, lack of collateral circulation was associated with new or worsening neurologic deficit (p<0.03, Fisher exact test), which in all cases occurred in the setting of PED construct thrombosis. Altered branch vessel flow was not associated with the use of adjunctive coils or the use of more than one PED construct. Conclusion Branch vessel occlusion is a well-known ramification from flow diversion, but rarely results in clinical deficits. Most patients with altered branch vessel flow (either slow or absent) have distal supply via collateral circulation. In our cohort with altered branch vessel flow, new or worsening neurologic symptoms were associated with absent collateral circulation. Disclosures S. Raymond: None. M. Koch: None. C. Stapleton: None. C. Torok: None. A. Patel: 2; C; Medtronic, Penumbra.