WEB Treatment of Ruptured Intracranial Aneurysms: Long-Term Follow-up of a Single-Center Cohort of 100 Patients.

BACKGROUND AND PURPOSE: The Woven EndoBridge device (WEB) was introduced for the intrasaccular treatment of wide-neck aneurysms without the need for adjunctive devices. We used the WEB as a primary treatment for 100 ruptured aneurysms regardless of neck size or location. In this study, we present the long-term follow-up of 78 surviving patients. MATERIALS AND METHODS: Between February 2015 and April 2017, one hundred ruptured aneurysms were treated with the WEB. For surviving patients, angiographic and clinical follow-up was scheduled at 3 months, and 3T MRA and clinical follow-up, at 6, 12, 36, and 60 months. Of 100 patients, 18 died during hospital admission, and in 4, the ruptured aneurysm was additionally treated. The remaining 78 patients had a mean follow-up of 51 months (median, 52 months; range, 5-84 months). There were 57 women and 21 men, with a mean age of 58.5 years (median, 59 years; range, 24-80 years). Of 78 aneurysms with long-term follow-up, 52 (66%) had a wide neck. RESULTS: Of 78 ruptured aneurysms, 56 (72%) remained completely occluded and 17 (22%) had a stable small neck remnant. Five of 78 aneurysms (6%; 95% CI, 2.4%-14.5%) reopened during follow-up and were additionally treated. There were no rebleeds during follow-up. CONCLUSIONS: Treatment of ruptured aneurysms with the WEB was safe and effective and has long-term results comparable with those of simple coiling of small-neck aneurysms. The WEB proved to be a valuable alternative to coils for both wide- and small-neck ruptured aneurysms without the need for stents, balloons, or antiplatelet therapy.

Endovascular Management of Intracranial Dural Arteriovenous Fistulas: Transarterial Approach.

In this second of 3 review articles on the endovascular management of intracranial dural AVFs, we discuss transarterial treatment approaches. The treatment goal is to occlude the fistulous point, including the most distal portion of the arterial supply together with the most proximal portion of the draining vein (ie, the "foot" of the vein), which can be accomplished with liquid embolic agents via transarterial access. Anatomic factors to consider when assessing the safety and efficacy of a transarterial approach using liquid embolic agents include location, angioarchitecture, and proximity of arterial feeders to both the vasa nervosum of adjacent cranial nerves and the external carotid-internal carotid/vertebral artery anastomoses. Anatomic locations typically favorable for transarterial approaches include but are not limited to the transverse/sigmoid sinus, cerebral convexity, and superior sagittal sinus. In this review article, we discuss the technical approaches, outcomes, potential complications, and complication avoidance strategies for transarterial embolization.

Endovascular Management of Intracranial Dural AVFs: Transvenous Approach.

In this third review article on the endovascular management of intracranial dural AVFs, we discuss transvenous embolization approaches. Transvenous embolization is increasingly popular and now the first-line approach for ventral dural AVFs involving the cavernous sinus and hypoglossal canal. In addition, transvenous embolization is increasingly used in lateral epidural dural AVFs in high-risk locations such as the petrous and ethmoid regions. The advantage of transvenous embolization in these locations is the ability to retrogradely embolize the draining vein and fistula while reducing the risk of ischemic cranial neuropathy or brain parenchymal infarction commonly feared from a transarterial approach. By means of coils ± ethylene-vinyl alcohol copolymer, transvenous embolization can achieve angiographic cure rates of 80%-90% in ventral locations. Potential complications include transient cranial neuropathy, neurologic deterioration due to venous outflow obstruction, and perforation while navigating pial veins. Transvenous embolization should be considered when dural AVFs arise in proximity to the vasa nervosum or extracranial-intracranial anastomoses.

Endovascular Management of Intracranial Dural AVFs: Principles.

Intracranial dural AVFs are abnormal communications between arteries that supply the dura mater and draining cortical veins or venous sinuses. They are believed to form as a response to venous insults such as thrombosis, trauma, or infection. Classification and management are dependent on the presence of drainage/reflux into cortical veins because such drainage markedly elevates the risk of hemorrhage or venous congestion, resulting in neurologic deficits. AVFs with tolerable symptoms and benign drainage patterns can be managed conservatively. Intolerable symptoms, presentation with hemorrhage/neurologic deficits, or aggressive drainage patterns are indications for intervention. Treatment options include microsurgical disconnection, endovascular transarterial embolization, transvenous embolization, or a combination. This is the first in a series of 3 articles on endovascular management of intracranial dural AVFs, in which we outline the principles and outcomes of endovascular treatment.

Ticagrelor versus Clopidogrel in the Dual Antiplatelet Regimen for Intracranial Stenting or Flow-Diverter Treatment for Unruptured Cerebral Aneurysms: A Single-Center Cohort Study.

BACKGROUND AND PURPOSE: Ticagrelor is a novel P2Y12 antagonist, and little is known about its efficacy and safety in the endovascular treatment of aneurysms. This study evaluated the efficacy and safety of ticagrelor versus clopidogrel for stent-assisted coiling or flow-diversion treatment in patients with unruptured cerebral aneurysms. MATERIALS AND METHODS: From November 2003 to February 2019, two hundred one patients (mean age, 57.5 years; 156 women) with 233 unruptured aneurysms underwent stent-assisted coiling or flow-diversion treatment. All patients received antiplatelet therapy of aspirin plus clopidogrel (clopidogrel group, 121 patients with 140 aneurysms) or aspirin plus ticagrelor (ticagrelor group, 80 patients with 93 aneurysms). The clinical and radiologic data in each group were retrospectively reviewed and compared. RESULTS: Two hundred thirty-six procedures were performed, including stent-assisted coiling (n = 101) and flow diversion (n = 135). At 90 days, the primary outcome-a composite of any stroke and death-occurred in 9.9% of the clopidogrel group and 8.6% of the ticagrelor group (P = .822). Ischemic stroke occurred in 10 (7.0%) of the clopidogrel group and 7 (7.5%) of the ticagrelor group (P > .999). Disabling stroke occurred in 4 (2.8%) in the clopidogrel group and in 4 (4.3%) in the ticagrelor group (P = .716). Ninety-day death occurred in 3 (2.1%) in the clopidogrel group and 1 (1.1%) in the ticagrelor group (P > .999). Any bleeding at 90 days occurred in 13 (9.2%) in the clopidogrel group and 6 (6.5%) in the ticagrelor group (P = .479). CONCLUSIONS: Ticagrelor appears to be as effective and safe as clopidogrel in stent-assisted coiling or flow-diversion treatment for unruptured cerebral aneurysms.

Facial Nerve Arterial Arcade Supply in Dural Arteriovenous Fistulas: Anatomy and Treatment Strategies.

BACKGROUND AND PURPOSE: Endovascular treatment of petrous dural AVFs may carry a risk of iatrogenic facial nerve palsy if the facial nerve arterial arcade, an anastomotic arterial arch that supplies the geniculate ganglion, is not respected or recognized. Our purpose was to demonstrate that the use of a treatment strategy algorithm incorporating detailed angiographic anatomic assessment allows identification of the facial nerve arterial arcade and therefore safe endovascular treatment. MATERIALS AND METHODS: This was a retrospective cohort study of consecutive petrous dural AVF cases managed at Toronto Western Hospital between 2006 and 2018. Our standard of care consists of detailed angiographic assessment followed by multidisciplinary discussion on management. Arterial supply, primary and secondary treatments undertaken, angiographic outcomes, and clinical outcomes were assessed by 2 independent fellowship-trained interventional neuroradiologists. RESULTS: Fifteen patients had 15 fistulas localized over the petrous temporal bone. Fistulas in all 15 patients had direct cortical venous drainage and received at least partial supply from the facial nerve arterial arcade. Following multidisciplinary evaluation, treatment was performed by endovascular embolization in 8 patients (53%) and microsurgical disconnection in 7 patients (47%). All patients had long-term angiographic cure, and none developed iatrogenic facial nerve palsy. CONCLUSIONS: By means of our treatment strategy based on detailed angiographic assessment and multidisciplinary discussion, approximately half of our patients with petrous AVFs were cured by endovascular treatment, half were cured by an operation, and all had preserved facial nerve function.

Artery of Davidoff and Schechter Supply in Dural Arteriovenous Fistulas.

The artery of Davidoff and Schechter is a dural branch of the posterior cerebral artery that can supply the meninges close to the falcotentorial junction. It is usually not identified on angiography except when enlarged in the setting of a dural AVF or meningioma. The impact on treatment of the artery of Davidoff and Schechter supply to a fistula is not well-described in the literature. Our retrospective analysis of patients with dural AVFs treated at the Toronto Western Hospital between 2006 and 2018 identified 6 patients with dural AVFs receiving supply from artery of Davidoff and Schechter (of a total of 173 patients with dural AVFs). All patients were initially treated by transarterial embolization using liquid embolic agents. Three patients required a second endovascular procedure partly due to residual supply from artery of Davidoff and Schechter, and in all cases, angiographic cure was obtained. The treatment approach, challenges encountered, and potential complications of treating such fistulas are described.

Acute Cortical Lesions in MELAS Syndrome: Anatomic Distribution, Symmetry, and Evolution.

BACKGROUND AND PURPOSE: Mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS) syndrome is a rare mitochondrial disorder affecting children and young adults. Stroke-like episodes are often associated with acute cortical lesions in the posterior cerebral cortex and are classically described as asymmetric and transient. In this study we assessed the anatomic distribution of acute cortical lesions, the incidence of symmetry, and the temporal evolution of lesions. MATERIALS AND METHODS: This was a retrospective cohort study of patients who had a confirmed genetic diagnosis of a pathogenic variant associated with MELAS and MR imaging performed at our center (2006-2018). Each MR imaging study was assessed for new lesions using T1, T2, FLAIR, DWI, ADC, and SWI. The anatomic location, symmetry, and temporal evolution of lesions were analyzed. RESULTS: Eight patients with the same pathogenic variant of MELAS (MT-TL1 m.3243A>G) with 31 MR imaging studies were included. Forty-one new lesions were identified in 17 of the studies (5 deep, 36 cortical). Cortical lesions most commonly affected the primary visual cortex, the middle-third of the primary somatosensory cortex, and the primary auditory cortex. Thirty of 36 cortical lesions had acute cortical diffusion restriction, of which 21 developed cortical laminar necrosis on subacute imaging. Six of 11 studies with multiple lesions showed symmetric cortical involvement. CONCLUSIONS: Acute cortical lesions in MELAS most commonly affect the primary visual, somatosensory, and auditory cortices, all regions of high neuronal density and metabolic demand. The most common pattern of temporal evolution is acute cortical diffusion restriction with subacute cortical laminar necrosis and chronic volume loss. Symmetric involvement is more common than previously described.

Mid-term 3T MRA follow-up of intracranial aneurysms treated with the Woven EndoBridge.

INTRODUCTION: Angiography is the standard follow-up modality for treated aneurysms with the Woven EndoBridge (WEB), and magnetic resonance angiography (MRA) is useful for extended follow-up. We present the results of WEB-treated aneurysms with angiographic follow-up at three months and at least 18 months' 3T MRA follow-up. MATERIALS AND METHODS: Included were 52 patients with 53 aneurysms treated with the WEB between February 2015 and July 2016. There were 29 women and 23 men with a mean age of 60 years (median 62, range 23-76). Mean aneurysm size was 6.2 mm (median 6, range 3-16 mm). RESULTS: 3T MRA follow-up was mean 19.6 months (median 18, range 18-36 months). One patient had an aneurysm remnant at three-month angiography that was additionally coiled and with stable complete occlusion at 18 months' 3T MRA follow-up. At three-month follow-up angiography, 44 aneurysms were completely occluded and eight had a neck remnant. At latest 3T MRA, stable complete occlusion was present in 43 aneurysms and stable neck remnant in eight. One posterior cerebral artery (PCA) dissection aneurysm was stable at three and six months but was enlarged and reopened at 18 months, confirmed with angiography. Focal signal loss by the proximal marker of the WEB was apparent in four patients without compromising diagnostic evaluation. CONCLUSION: WEB-treated aneurysms with adequate occlusion at three-month angiography remained stable during serial 3T MRA follow-up of 18-36 months. One PCA aneurysm reopened during the 6- to 18-month interval. Once the WEB-treated aneurysm is adequately occluded in the short term, later reopening is uncommon.

The New Low-Profile WEB 17 System for Treatment of Intracranial Aneurysms: First Clinical Experiences.

BACKGROUND AND PURPOSE: The Woven EndoBridge (WEB) is an intrasaccular flow diverter intended to treat wide-neck aneurysms. The latest generation WEBs needed a 0.021-inch microcatheter in the small sizes. Recently, a lower profile range of WEBs compliant with a 0.017-inch microcatheter (WEB 17) has been introduced. We present the first clinical results of treatment of both ruptured and unruptured aneurysms with the WEB 17. MATERIALS AND METHODS: Between December 2016 and September 2017, forty-six aneurysms in 40 patients were treated with the WEB 17. No supporting stents or balloons were used. Twenty-five aneurysms were ruptured (54%). There were 6 men and 34 women (mean age, 62 years; median, 63 years; range, 46-87 years). The mean aneurysm size was 4.9 mm (median, 5 mm; range, 2-7 mm). RESULTS: There were 2 thromboembolic procedural complications without clinical sequelae and no ruptures. The overall permanent procedural complication rate was 0% (0 of 40; 97.5% CI, 0%-10.4%). Imaging follow-up at 3 months was available in 33 patients with 39 aneurysms (97.5% of 40 eligible aneurysms). In 1 aneurysm, the detached WEB was undersized and the remnant was additionally treated with coils after 1 week. This same aneurysm reopened at 3 months and was again treated with a second WEB. One other aneurysm showed persistent WEB filling at 3 months. Complete occlusion was achieved in 28 of 39 aneurysms (72%), and 9 aneurysms (23%) showed a neck remnant. CONCLUSIONS: The WEB 17 is safe and effective for both ruptured and unruptured aneurysms. The WEB 17 is a valuable addition to the existing WEB size range, especially for very small aneurysms.

Treatment of cranial dural arteriovenous fistulas with exclusive cortical venous drainage: A single-center cohort of 35 patients.

Background and purpose Dural arteriovenous fistulas (DAVFs) with cortical venous drainage often present with hemorrhage or neurological deficits and prompt treatment is indicated. Disconnection of the draining vein is considered curative. We present the multimodality treatment results of 35 patients with cranial DAVFs with exclusive cortical venous drainage. Materials and methods Between January 2010 and January 2017, 35 consecutive patients with cranial dural fistulas with exclusive cortical venous drainage were treated. There were 27 men and eight women, mean age 68 years (range 45-87). Clinical presentation was hemorrhage in 23 (66%), pulsatile bruit in two (6%), seizures in one (3%) and blurred vision in one (3%). In eight patients (22%), the DAVF was an incidental finding. Location of the DAVFs was convexity in 25 (71%), posterior fossa in eight (23%) and tentorium in two (6%). Results Surgery was performed in four patients with anterior cranial fossa fistulas and in one patient with a tentorial dural fistula. In 30 patients, embolization with Onyx via the arterial route was the primary treatment with complete obliteration in one session in 25 patients. Additional surgical or endovascular sessions were necessary in five patients after incomplete embolization and in one patient after incomplete surgery. Obliteration was confirmed with angiography after three months. There were no procedural complications. Conclusions Patients with dural fistulas with cortical venous drainage were cured with a strategy of arterial endovascular treatment with Onyx and surgery. These techniques were either primarily successful or complementary. There were no complications of treatment.

WEB Treatment of Ruptured Intracranial Aneurysms: A Single-Center Cohort of 100 Patients.

BACKGROUND AND PURPOSE: The Woven EndoBridge device was recently introduced for the intrasaccular treatment of wide-neck aneurysms without the need for adjunctive devices. We present our results of the primary treatment of ruptured aneurysms with the Woven EndoBridge regardless of location or neck size. MATERIALS AND METHODS: Between February 2015 and April 2017, 100 ruptured aneurysms were selectively treated with the Woven EndoBridge. No supporting stents or balloons were used. There were 71 women treated (mean patient age, 59 years; median age, 60 years; range, 23-82 years). RESULTS: The mean aneurysm size was 5.6 mm (range, 3-13 mm), and 42 aneurysms were ≤4 mm. Sixty-six aneurysms (66%) had a wide neck, defined as ≥4 mm or a dome-neck ratio ≤1.5. There was 1 procedural rupture without sequelae. In 9 patients (9%), thromboembolic complications occurred. One poor grade patient died; neurologic deficits remained in 3. Overall treatment-related morbidity-mortality was 4% (4 of 100; 95% CI, 1.2%-10.2%).Two of 100 aneurysms were initially incompletely occluded and were additionally treated early after initial intervention. Of 80 eligible patients, 74 (93%) had 3-month angiographic follow-up. Fifty-four aneurysms (73%) were completely occluded, 17 (23%) had a small neck remnant, and 3 (4%) were incompletely occluded. One patient was additionally treated with a second Woven EndoBridge, and in 2 patients, additional treatment is scheduled. The overall reopening/retreatment rate was 6.8% (5 of 74; 95% CI, 2.6%-15.2%). There were no rebleeds during follow-up. CONCLUSIONS: Treatment of small ruptured aneurysms with the Woven EndoBridge was safe and effective. The Woven EndoBridge proved to be a valuable alternative to coils without the need for stents or balloons.

Tentorial Dural Arteriovenous Fistulas: A Single-Center Cohort of 12 Patients.

OBJECTIVE: Tentorial dural arteriovenous fistulas usually drain into cortical veins and often present with hemorrhage. Treatment goal is occlusion of the draining vein, either by surgery or endovascular techniques. We present the multimodality treatment results of 12 patients with tentorial dural arteriovenous fistulas. MATERIALS AND METHODS: Between January 2007 and January 2017, 12 consecutive patients with tentorial dural arteriovenous fistulas were treated. There were 11 men and 1 woman with a mean age of 62 years (range 44-85). Clinical presentation was hemorrhage in 8 (67%), pulsatile tinnitus in 2 (17%) and an incidental finding in 2 (17%). The fistula location was at the tentorium cerebelli in 5 (42%), the torcula Herophilii in 4 (33%) and petroclival in 3 (25%). RESULTS: In 11 patients, arterial embolization with Onyx or PHIL was the primary treatment. Complete obliteration was achieved in one session in 5 (45%) and in 2 sessions in 4 (36%). In 2 patients additional surgery was needed. Primary surgery was performed in 1 patient followed by endovascular coil occlusion via the venous route. One patient with exclusive pial feeders from the posterior inferior cerebellar artery had a clinically silent P3 occlusion during trans arterial embolization. Finally, all 12 fistula were completely occluded, confirmed with angiography after 8-12 weeks. There were no permanent procedural complications. CONCLUSION: Patients with tentorial dural arteriovenous fistulas were effectively and safely cured with a strategy of endovascular treatment with various techniques and surgery. Surgical and endovascular techniques are complementary in the treatment of these challenging vascular disorders.

4D-CTA in neurovascular disease: a review.

CT angiography is a widely used technique for the noninvasive evaluation of neurovascular pathology. Because CTA is a snapshot of arterial contrast enhancement, information on flow dynamics is limited. Dynamic CTA techniques, also referred to as 4D-CTA, have become available for clinical practice in recent years. This article provides a description of 4D-CTA techniques and a review of the available literature on the application of 4D-CTA for the evaluation of intracranial vascular malformations and hemorrhagic and ischemic stroke. Most of the research performed to date consists of observational cohort studies or descriptive case series. These studies show that intracranial vascular malformations can be adequately depicted and classified by 4D-CTA, with DSA as the reference standard. In ischemic stroke, 4D-CTA better estimates thrombus burden and the presence of collateral vessels than conventional CTA. In intracranial hemorrhage, 4D-CTA improves the detection of the "spot" sign, which represents active ongoing bleeding.