The Woven EndoBridge (WEB; MicroVention, Aliso Viejo, CA, USA) intrasaccular flow disruptor is a therapeutic option for wide neck bifurcation intracranial aneurysms that does not require the use of adjunctive techniques such as stents or balloon remodeling. As with other endovascular devices, displacement of the WEB is a recognized complication. Few reports have been published regarding the management of this type of complication. We describe a case of retrieval of a displaced WEB using a Solitaire Platinum revascularization device (Medtronic, Minneapolis, MN, USA). Interventionists should be aware of this option in the management of such a complication.

Historically, obesity has been identified as one of the most important risk factors for developing cardiovascular diseases including stroke; however, a theory called “The Obesity Paradox” has been recently considered. The paradoxical theory is that obese or overweight patients (according to body mass index score) can have better outcomes compared to leaner or malnourished patients. The paradox was initially discovered in patients with heart failure. The purpose of this manuscript was to investigate whether this paradox also applies to stroke patients, according to information available in the current literature.

PurposeFour key bench-top tests, including trackability, conformability, wall-apposition, and bending stiffness, were performed to understand the mechanical characteristics in 3 different types of stents applicable for treatment of intracranial atherosclerotic stenosis: Balloon-expandable D+Storm, Pro-Kinetic Energy, and self-expandable Wingspan stents.Materials and MethodsTrackability was assessed by measuring the tracking forces of each stent with its delivery systems. Conformability and wall apposition were quantified and analyzed using curved vessel models. A 3-point bending test was employed to evaluate bending stiffness.ResultsD+Storm showed the lowest tracking forces while the conformability of the Wingspan stent was superior to that of the tested stents. Pro-Kinetic Energy and D+Storm had better wall apposition in curved vessels than the Wingspan stent. Bending stiffness of the Wingspan stent was notably lower, whereas no significant differences were found between D+Storm and Energy. Pro-Kinetic Energy and D+Storm not only indicated lower gap ratios between the struts and the vessel wall but also maintained good wall apposition even in the curved model.ConclusionThese bench-top measurements may provide clinicians with useful information in regard to selecting suitable stents for treatment of intracranial atherosclerotic stenosis.

PurposeIn acute middle cerebral artery (MCA) occlusion, collateral vessels provide retrograde supply to the occluded territory. We hypothesized that such collateral flow reduces perfusion of the non-occluded donor region (steal effect).Materials and MethodsPatients with an MCA occlusion with opacification of both ipsi- and contralateral anterior cerebral arteries (ACA) on angiography prior to endovascular treatment were selected. Arteriovenous transit time (AVTT) for both ACA territories was compared for different grades of collateral supply to the MCA territory. In addition, the influence of diabetes and hypertension was analyzed. After successful revascularization, AVTT was re-assessed to determine reversibility.ResultsForty-one patients were analyzed. An AVTT of 8.6 seconds (standard deviation [SD] 2.4 seconds) was seen in the ACA territory of the affected hemisphere in comparison to 6.6 seconds (SD 2.1 seconds) for the contralateral side (P<0.001). A more prolonged (but not significant) AVTT was seen in cases with a higher collateral grade. No difference in AVTT was seen in patients with diabetes or hypertension. After successful MCA revascularization, AVTT delay was 7.4 seconds (SD 2.1 seconds).ConclusionA cerebral steal effect occurs in patients with an acute MCA occlusion, probably related to augmented flow to the penumbra area.

Spinal dural arteriovenous fistulae (AVF) are rare and can result in spinal cord dysfunction. We present one such case wherein the patient presented with a venous congestive myelopathy. Magnetic resonance imaging showed a syrinx formation, spinal cord edema, and flow voids. Digital subtraction angiography confirmed the dural AVF, which was treated with embolization. The syrinx disappeared, other spinal cord changes improved, and the patient had remarkable clinical improvement. The case is presented to draw attention to the rare formation of a syrinx in a spinal dural arteriovenous fistula and its disappearance after successful embolization.

PurposeWith advancing endovascular technology and increasing interest in minimally invasive intra-arterial therapies such as stem cell and chemotherapy for cerebral disease, the establishment of a translational model with cerebral circulation accessible to microcatheters is needed. We report our experience catheterizing canine cerebral circulation with microcatheters, present high-resolution angiographic images of the canine vascular anatomy, describe arterial branch flow patterns and provide measurements of canine arterial conduits.Materials and MethodsAngiograms were performed on 10 intact purpose-bred hounds. Angiography, measurements of arterial conduits and catheterization information for intracranial arterial branches were obtained.ResultsSelective and superselective cerebral angiography was successful in all subjects. Relevant arterial mean diameters include the femoral (4.64 mm), aorta (9.38 mm), external carotid (3.65 mm), internal carotid arteries (1.6 mm), vertebrobasilar system and Circle of Willis branches. Catheterization of the Circle of Willis was achieved via the posterior circulation in all subjects tested (n=3) and the use of flow directed microcatheters resulted in reduced arterial tree deformation and improved superselection of intracranial vessels. Catheterization of the intracranial circulation was attempted but not achieved via the internal carotid artery (n=7) due to its tortuosity and subsequent catheter related vasospasm.ConclusionThe canine cerebral vasculature is posterior circulation dominant. Anterior circulation angiography is achievable via the internal carotid artery, but direct cerebral arterial access is best achieved via the posterior circulation using flow-directed microcatheters. It is feasible to deliver intra-arterial therapies to selective vascular territories within the canine cerebral circulation, thus making it a viable animal model for testing novel intra-arterial cerebral treatments.

PurposeWe applied a low-dose fluoroscopic protocol in routine diagnostic cerebral angiography and evaluated the feasibility of the protocol.Materials and MethodsWe retrospectively reviewed a total of 60 patients who underwent diagnostic cerebral angiography for various neurovascular diseases from September to November 2019. Routine protocols were used for patients in the first phase and low-dose protocols in the second phase. We compared radiation dose, fluoroscopy time, and complications between groups.ResultsAge, diseases, and operators were not significantly different between the two groups. The mean fluoroscopy dose significantly decreased by 52% in the low-dose group (3.09 vs. 6.38 Gy·cm2); however, the total dose was not significantly different between the two groups (34.07 vs. 33.70 Gy·cm2). The total fluoroscopic time was slightly longer in the low-dose group, but the difference was not statistically significant (12.2. vs. 12.5 minutes). In all patients, angiography was successfully performed without complications.ConclusionThe low-dose fluoroscopy protocol is feasible to apply for diagnostic cerebral angiography in that this protocol could significantly reduce the fluoroscopic dose.

Carotid blowout syndrome (CBS) is a fatal complication of head and neck cancer. Endovascular treatment, particularly deconstructive embolization, is effective for CBS, but it might result in thromboembolic events. We report the case of a 57-year-old man with underlying recurrent head and neck cancer who had CBS. The patient received endovascular embolization of the right internal, external, and common carotid arteries. Right internal carotid artery to middle cerebral artery embolic occlusion was noted immediately after the procedure, and left-sided weakness and facial palsy were found. Ipsilateral suprabulbar cervical internal carotid artery puncture was performed under fluoroscopic guidance, and rescue suction thrombectomy was successful. The patient had no significant neurological sequela. Transcarotid intraarterial thrombectomy is a reasonable method for managing postembolization large vessel occlusion, even in the neck, after irradiation.

PurposeIn Korea, endovascular treatment (EVT) for intracranial aneurysms (IAs) has increased steadily. We conducted a nationwide survey to evaluate the current status of EVT for IAs and to identify treatment preference in the real world.Materials and MethodsA Google online survey was distributed to representative clinicians at hospitals treating IAs, where members of Korean Society of Interventional Neuroradiology (KSIN). The data was collected from October 2017 to December 2017. The responding hospitals were divided into 2 groups (tertiary and non-tertiary hospitals). And variable factors involved in decision making for treatment were evaluated.ResultsIn total, 73 hospitals (tertiary: 37, non-tertiary: 36) responded to the survey. Most hospitals that responded had over 100 cases of diagnostic angiography (93%) and over 50 cases of EVT for IAs (74%) performed in 2016. The proportion of EVT for ruptured aneurysms in non-tertiary hospitals was significantly higher than tertiary hospitals (49% vs. 9%). The proportion of EVT for unruptured aneurysms at non-tertiary hospitals was significantly higher than tertiary hospitals (66% vs. 44%). Most physicians tended to make decision for treatment on location, shape, and size of unruptured IAs and patients’ age, more than the results from previous clinical trials for unruptured IAs. Although EVT was preferred for older patients (age >70) with unruptured IAs (99%), surgical clipping was still considered as the first treatment of choice for younger patients (age 30 to 50 years) at considerable rates (56%). Over two-thirds of respondents preferred surgical clipping for middle cerebral artery aneurysms, while EVT was preferred initially at other locations.ConclusionThis nationwide survey showed that EVT is considered as the first treatment modality for IAs and there is a discrepancy between current guidelines and real-world practice for decision making of treatment options.

PurposeAlthough carotid endarterectomy (CEA) is recommended as a treatment for carotid stenosis rather than carotid artery stenting (CAS), CAS has been preferred in Korea. The aim of this study was to analyze long-term outcomes after CAS compared with CEA using Korean nationwide insurance data.Materials and MethodsWe obtained all data from the nationwide database of the Health Insurance Review & Assessment Service (HIRA) during the study period using several codes regarding the procedure or operation. We included the HIRA data, which included at least one-year follow-up after the procedures. The outcomes associated with both procedures were death, recurrence of ischemic stroke, and admission for cerebral hemorrhage.ResultsA total of 16,065 eligible patients who were treated with CAS or CEA between 1 January 2007 and 31 December 2016 were analyzed. The number of patients with CAS and CEA was 12,173 (75.8%) and 3,892 (24.2%), respectively. 8,976 patients (55.9%) were classified as symptomatic patients. CAS was associated with a higher risk of all-cause mortality (adjusted hazard ratio [HR], 1.282; 95% confidence interval [CI], 1.173–1.400). The adjusted rates for recurrent ischemic stroke and cerebral hemorrhage between CAS versus CEA were 24.9% versus 15.9% (HR, 1.474; 95% CI, 1.325–1.639) and 1.5% versus 0.9% (HR, 2.026; 95% CI, 1.322–3.106), respectively. In young symptomatic patients, there was no statistically significant difference in all-cause mortality and cardiovascular death between CAS and CEA.ConclusionOur study using Korean nationwide insurance data demonstrated similar results to previous studies. Until further evidence of CAS is established through prospective studies, CAS should be performed in selected patients according to current guidelines.