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We have epitaxially grown Si/β-FeSi2/Si (SFS) structures with β-FeSi2 particles on Si(001), and SFS structures with β-FeSi2 continuous films on both Si(001) and Si(111) substrates by molecular-beam epitaxy. All the samples exhibited the same photoluminescence (PL) peak wavelength of approximately 1.54 μm at low temperatures. However, the PL decay times for the 1.54 μm emission were different, showing that the luminescence originated from different sources. The decay curves of the SFS structures with β-FeSi2 continuous films were fitted assuming a two-component model, with a short decay time (τ∼10 ns) and a long decay time (τ∼100 ns), regardless of substrate surface orientation. The short decay time was comparable to that obtained in the SFS structure with β-FeSi2 particles. The short decay time was due to carrier recombination in β-FeSi2, whereas the long decay time was probably due to a defect-related D1 line in Si. We obtained 1.6 μm electroluminescence (EL) at a low current density of 2 A/cm2 up to around room temperature. The temperature dependence of the EL peak energy of the SFS diodes with β-FeSi2 particles can be fitted well by the semiempirical Varshni’s law. However, EL peak positions of the SFS diodes with the β-FeSi2 films showed anomalous temperature dependence; they shifted to a higher energy with increasing temperature, and then decreased. These results indicate that the EL emission originated from several transitions. [ABSTRACT FROM AUTHOR]

The photoluminescence (PL) decay times of Si/[beta]-Fe[Si.sub.2]/Si (SFS) double-heterostructure (DH) on both Si(001) and Si(111) substrates as well as those of SFS with [beta]-Fe[Si.sub.2] particles are examined. The results have shown that other luminescence such as D1 line has contributed to the electroluminescence (EL) from the SFS DH light emitting diodes (LEDs).

Abstract: The p-Si/p-β-FeSi2/p-Si/n-Si light-emitting diode (LED) was fabricated by molecular beam epitaxy (MBE) on Si(111) substrates. Compared to our previous p-Si/p-β-FeSi2/n-Si double heterostructures (DH) LED, the turn-on voltage in the current–voltage (I–V) characteristics increased by approximately 0.2 V, meaning that defect densities at around the p–n junction were reduced. However, Si-related EL (1.05 eV) became dominant unexpectedly, and thus EL of β-FeSi2 was suppressed accordingly. The origin of the luminescence is considered to be transitions via defect levels (1.05 eV) being due probably to Fe-B complex. [Copyright &y& Elsevier]

Abstract: We have fabricated single-, three- and five-layered Si/β-FeSi2/Si (SFS) double heterostructures (DH) on Si (001) substrates by reactive deposition epitaxy (RDE) for β-FeSi2 and by molecular beam epitaxy (MBE) for Si. Time-resolved photoluminescence (PL) measurements revealed that the luminescence at 1.54μm was composed of fast (16ns) and slow (150ns) components at 8K. These are thought to originate from β-FeSi2 and the defect-related D1 line in Si, respectively. 1.6μm electroluminescence (EL) was obtained at room temperature (RT) from the five-layered SFS DH for current densities above 20A/cm2. [Copyright &y& Elsevier]

Abstract: Si/β-FeSi2/Si (SFS) heterostructures were grown epitaxially on Si(001) by reactive deposition epitaxy (RDE) for β-FeSi2 and by molecular beam epitaxy (MBE) for Si. Distinct 1.54-μm photoluminescence was observed at 77 K for SFS with a β-FeSi2 thickness ranging from 5 to 10 nm. When the thickness of the β-FeSi2 layer was increased up to 40 nm, the PL intensity of β-FeSi2 decreased and the full-width at half maximum (FWHM) of the PL peak increased. Reflection high-energy electron diffraction observation revealed that the Si overlayer has a tendency to form polycrystalline structures with the increase of β-FeSi2 thickness. The degradation of PL was also observed for samples annealed at 900 °C. [Copyright &y& Elsevier]

Abstract: Ferromagnetic Fe3Si/CaF2/Si hybrid structures were grown epitaxially on Si(111) by molecular beam epitaxy. It was difficult to prevent inclusion of FeSi in the grown films in the case that Si and Fe were directly deposited on the Si substrate. This problem was overcome by inserting a CaF2 epitaxial film between the Fe3Si and Si substrate. Fe3Si films were grown epitaxially on the CaF2 at 400 °C. A distinct square-like hysteresis loop with coercive field of approximately 20 Oe was obtained in the magnetic field dependence of Kerr rotation at room temperature (RT). The saturation magnetization was approximately 550 emu/cm3 at RT by a super conducting quantum interference device magnetometer. [Copyright &y& Elsevier]

Aneurysmal subarachnoid hemorrhage (aSAH) is a critical condition with high in-hospital mortality rates. Delayed cerebral ischemia (DCI), a secondary complication associated with aSAH, can also contribute to morbidity and mortality. Although draining the hematoma from the subarachnoid space has been considered effective in preventing DCI, the placement of a drainage system could increase the risk of bacterial meningitis and ventriculitis. This study aimed to examine the association between meningitis following aSAH and the occurrence of DCI, focusing on the role of cerebral vasospasm. Patients who underwent endovascular coiling or surgical clipping for aSAH from April 2001 to March 2022 were included in this study, while those who did not undergo postoperative drainage were excluded. The patient's clinical characteristics, treatment modalities, and outcomes were then analyzed, after which logistic regression was used to assess the odds ratios (OR) for DCI. A total of 810 patients with aSAH were included in this study. Meningitis following aSAH was identified as an independent factor associated with DCI (odds ratio 5.0 [95% confidence intervals (CI) 2.3-11]). Other significant factors were female sex (odds ratio 1.5 [95% CI 0.89-2.5]) and surgical clipping (odds ratio 2.1 [95% CI 1.3-3.4]). This study demonstrated a significant association between meningitis following aSAH and the development of DCI, suggesting that the inflammatory environment associated with meningitis may contribute to cerebral vasospasm. Early recognition and treatment of meningitis in patients with aSAH could reduce the risk of DCI and improve patient outcomes.

Despite advancements in neurosurgical techniques, subarachnoid hemorrhage(SAH) caused by the rupture of a partially thrombosed intracranial giant aneurysm remains a challenging clinical entity. This report describes the successful treatment of an 80-year-old male patient with SAH due to a ruptured, partially thrombosed intracranial giant aneurysm. The patient underwent a staged endovascular strategy using a flow diverter. The patient presented with SAH secondary to a ruptured, partially thrombosed intracranial giant aneurysm located at the C2 portion of the internal carotid artery and involving the origin of the posterior communicating artery(Pcom). Imaging revealed a dorsomedial rupture point on the aneurysm. A two-stage endovascular intervention(IVR) was performed. The first stage involved coil embolization aimed at covering the rupture point. Following the resolution of the vasospasm and the acute phase of SAH, the second stage involved the deployment of a pipeline embolization device. Digital subtraction angiography performed one month after the second stage IVR demonstrated a significant reduction in aneurysm filling, with preserved flow to the Pcom artery. We will discuss the technical details and rationale behind the staged endovascular approach in this complex case.

Objective: In carotid artery stenting (CAS) for internal carotid artery stenosis, the stent is often selected according to the plaque properties and arterial tortuosity. In our institute, an open-cell stent is used as the first-line stent regardless of the characteristics of the lesion. This study was performed to examine the outcome of CAS with an open-cell stent as the real-world results., Methods: In total, 811 CAS procedures using open-cell stents were performed for internal carotid artery stenosis from April 2002 to December 2019. Of these patients, we excluded those with hyperacute conditions for which CAS was performed within 3 days of onset, those in whom acute mechanical thrombectomy was performed simultaneously with CAS, and those with stenosis due to arterial dissection. Thus, 734 patients were retrospectively analyzed. Perioperative and long-term outcomes and risk factors for perioperative infarction were investigated., Results: The periprocedural stroke rate and mortality rate were 3.7% (27/734) and 0.4% (3/734), respectively. Low-echoic plaque was a significant risk factor for periprocedural stroke in both univariate (P < 0.03) and multivariate (odds ratio, 2.69; 95% confidence interval, 1.14-6.66; P = 0.02) analyses. Cerebral infarction and high grade restenosis were observed in 15 (2.0%) and 17 (2.3%) patients during a median 50-month follow-up., Conclusions: CAS with open-cell stents showed good results in terms of both the postoperative stroke incidence and long-term severe restenosis rate. However, low-echoic plaque was a risk factor for perioperative stroke incidence, which should be considered when deciding on the indication for CAS with an open-cell stent., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: In mechanical thrombectomy for tandem occlusions in vertebrobasilar stroke, distal emboli from the vertebral artery lesion should be prevented. However, no suitable embolic protection devices are currently available in the posterior circulation. Here, the authors describe the case of a vertebral artery lesion effectively treated with a closed-tip stent retriever as an embolic protection device in the posterior circulation., Observations: A 65-year-old male underwent mechanical thrombectomy for basilar artery occlusion, with tandem occlusion of the proximal vertebral artery. After basilar artery recanalization via the nonoccluded vertebral artery, a subsequent mechanical thrombectomy was performed for the occluded proximal vertebral artery. To prevent distal embolization of the basilar artery, an EmboTrap III stent retriever was deployed as an embolic protection device within the basilar artery to successfully capture the thrombus., Lessons: A stent retriever with a closed-tip structure can effectively capture thrombi, making it a suitable distal embolic protection device in the posterior circulation.

Objective: Although consensus has been reached regarding the use of mechanical thrombectomy for acute large anterior circulation occlusion, its effectiveness in patients with posterior circulation occlusion remains unclear. This study aimed to establish the determining factors for good clinical outcomes of mechanical thrombectomy for posterior circulation occlusion., Methods: We extracted cases of acute large vessel occlusion (LVO) in the posterior circulation from a database comprising 536 patients who underwent mechanical thrombectomy at our hospital between April 2015 and March 2021., Results: Fifty-two patients who underwent mechanical thrombectomy for LVO in the posterior circulation were identified. Five patients with simultaneous occlusion of the anterior and posterior circulation were excluded; finally, 47 patients were included in this study. The median patient age was 78 years, and 36% of the patients were women. The median National Institutes of Health Stroke Scale (NIHSS) score on admission was 31, the median posterior circulation-Alberta Stroke Program Early Computed Tomography Score (pc-ASPECTS) was 8, and the median Basilar Artery on Computed Tomography Angiography (BATMAN) score was 6. The rate of good recanalization (Thrombolysis in Cerebral Infarction scale grades 2b and 3) was 96%, and a good prognosis (modified Rankin Scale score of 0-2 at 90 days) was achieved in 19 patients (40%). The median pc-ASPECTS was significantly higher in the good prognosis group than in the poor prognosis group (10 vs. 7; p = 0.007). The median NIHSS score at presentation was significantly lower in the good prognosis group than in the poor prognosis group (17 vs. 34; p = 0.02). The median BATMAN score was significantly higher in the good prognosis group than in the poor prognosis group (8 vs. 3.5; p = 0.0002). Multivariate analysis showed that an NIHSS score ≦ 20 at presentation was the only independent factor for good prognoses., Conclusion: The prognosis of mechanical thrombectomy for posterior circulation LVO was better in patients with lower NIHSS scores at presentation., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Objective: According to benchtop studies, the oversizing of a Pipeline embolization device (PED) relative to the parent artery leads to a significant increase in porosity and potentially compromises aneurysm occlusion as well as transitional zone (TZ) formation around the neck of aneurysms. However, no clinical assessment has been reported. Here this potential was studied by measuring the dynamic changes of PEDs in the clinical time course., Methods: The authors retrospectively examined 124 anterior circulation unruptured aneurysms in 114 consecutive patients treated with a PED between July 2015 and December 2020 at their institution. The authors excluded 77 cases of 68 patients with adjunctive coil embolization or multiple stents that could affect the PED dynamics and measurements, and 47 aneurysms in 46 patients were included. Measurements were performed before, immediately after, and 6 months after treatment, and then at intervals of 6 months to 1 year after that for nonocclusion cases., Results: Complete occlusion was achieved in 79.0% and incomplete occlusion in 21.0% at last follow-up. The PED length immediately after deployment was 136% nominal length. A multivariable regression analysis revealed that age (OR 1.11/year; p = 0.02) and PED elongation from nominal length (OR 1.31/mm; p = 0.012) were independently associated with a higher rate of incomplete occlusion at the last follow-up. TZ formation did not affect the occlusion rate., Conclusions: PED elongation from the nominal length is a new predictor of incomplete aneurysm occlusion. The PED showed vascular remodeling by changing its diameter and length in the clinical course. TZ formation was remodeled and did not affect the occlusion rate.

Background: An exchange maneuver is useful for the delivery of devices to target vessels. However, hemorrhagic complications can occur due to vessel perforation during an exchange maneuver. In addition, the exchange is often challenging due to unfavorable anatomy. Center Wire is an exchange-length wire with a nondetachable stent that was developed to improve navigation and stability during exchange maneuvers. The aim of this study is to investigate the safety and efficacy of Center Wire of the anchor wire technique during neuroendovascular treatment., Methods: Ten patients with intracranial aneurysms were treated after signing a Certified Review Board-approved consent. Anchor wire technique was used in all patients to navigate catheters to the target vessel for aneurysm treatment., Results: Anchor wire technique was successfully applied in all 10 cases using Center Wire. One device-related incident of vasospasm occurred which was asymptomatic. No device-related dissection, perforation, or thromboembolic events occurred. One patient had intraoperative aneurysm rupture during coil placement which was treated immediately without clinical consequences. Two patients had postoperative ischemic strokes due to thrombotic occlusion of branches originating from the aneurysm which were unrelated to the device., Conclusions: This first-in-human trial of Center Wire demonstrated the safety and efficacy of the anchor wire technique for neuroendovascular treatment in a strictly regulated prospective registry trial.

Objectives: Flow diverter or stent implantation to intracranial target lesion requires large inner diameter microcatheter navigation. The exchange method using stiff long wire is often necessary if it is difficult to navigate over the regular guidewire. However, this method has an intrinsic risk of vessel damage and may cause severe complications. We investigated the safety and efficacy of a new device, the Stabilizer device for navigation in a first-in-human clinical trial under the Certified Review Board agreement., Materials and Methods: The Stabilizer is a 320 cm length exchange wire with a stent for anchoring and is compatible with a 0.0165" microcatheter. The trial design is a prospective single-arm open-label registry. Inclusion criteria are elective flow diverter treatment or stent-assisted coiling, expected to be difficult to navigate a microcatheter with a regular micro guidewire, and obtained documented consent. The primary endpoint of the study was a hemorrhagic complication., Results: Five patients were enrolled in this trial. The median age is 52 years, ranges from 41 to 70, and all patients were female. Three aneurysms were located on the internal carotid artery, one on the vertebral artery, and one on the basilar artery. Basilar artery aneurysm was treated by stent-assisted coiling and others were treated by flow diverter deployment. All cases successfully navigate microcatheter for the treatment by the trial method using Stabilizer device without any adverse event., Conclusions: The results from this first-in-human consecutive five cases show the safety of the Stabilizer device in neuro-endovascular therapy for navigation of devices to the intracranial target lesion., Competing Interests: The authors declare the following conflict of interests: This trial received trial devices from Bolt Medical, without specific grant. Grant from Kobe City Medical Center General Hospital support this trial. The authors, NS, NK and ST, were consultants of Bolt Medical at the treatment, but declare that this trial was conducted in the absence of any commercial or financial relationships that could be constructed as a potential conflict of interest. 10.13039/100007057NS received a research grant from Biomedical Solutions, 10.13039/501100002973Daiichi-Sankyo, and Terumo; lecturer's fees from Asahi-Intec, Biomedical Solutions, 10.13039/501100002973Daiichi-Sankyo, and Medtronic; membership on the advisory boards for Johnson&Johnson, 10.13039/100004374Medtronic and 10.13039/501100008645Terumo without related this manuscript. HI received lecturer's fee from 10.13039/100004374Medtronic. NK has been a consultant for Stryker and Medtronic. 10.13039/501100004347ST received research funds from Biomedical Solutions, Rapid Medical and Medtronic, and a consultant for TG Medical, 10.13039/100008476Irvine Neurovascular, Balt USA, Cerenovus, 10.13039/100004374Medtronic, Phenox GmbH, MicroVention, Kaneka USA, Century Medical Inc., EnCompass, NVMedTech, and 10.13039/100008894Stryker. The other authors have no personal or financial interest in any of the materials or devices described in this article., (© 2023 The Author(s).)

Performance of the dialysis membrane is strongly dependent upon the physicochemical structure of the membrane. The objective of this study is to devise a new in vitro evaluation technique to quantify the physicochemical structures of the membrane. Three commercial dialyzers with cellulose triacetate (CTA), asymmetric CTA (termed ATA ® ), and polyether sulfone (PES) membranes (Nipro Co., Osaka, Japan) were employed for investigation. Forward and backward ultrafiltration experiments were performed separately with aqueous vitamin B 12 (MW 1355), α-chymotrypsin (MW 25,000), albumin (MW 66,000) and dextran solutions, introducing the test solution inside or outside the hollow fiber (HF), respectively. Sieving coefficients (s.c.) for these solutes were measured under the test solution flow rate of 200 mL/min and the ultrafiltration rate of 10 mL/min at 310 K, according to the guidelines provided by Japanese academic societies. We defined the ratio of s.c. in the backward ultrafiltration to that in the forward ultrafiltration and termed it the index for asymmetricity (IA). The IA values were unity for vitamin B 12 and α-chymotrypsin in all three of the dialyzers. The IA values for albumin, however, were 1.0 in CTA, 1.9 in ATA ® , and 3.9 in PES membranes, respectively, which corresponded well with the fact that CTA is homogeneous, whereas ATA ® and PES are asymmetrical in structure. Moreover, the asymmetricity of ATA ® and PES may be different by twofold. This fact was verified in continuous basis by employing dextran solution before and after being fouled with albumin. These findings may contribute to the development of a novel membrane for improved success of dialysis therapy.

In the treatment of an intracranial aneurysm with the flow diverter, the combined use of coil embolization can help promote subsequent progressive thrombosis within the aneurysm sac and reduce the risk of delayed aneurysm rupture. This study retrospectively reviewed outcomes of patients who had undergone the Pipeline Embolization Device (PED) with adjunctive coil embolization (PED/coil) at a single center to determine its safety and efficiency. Patients with internal carotid artery aneurysms following an intradural component were selected for PED/coil between 2015 and 2020. All patients were premedicated with dual antiplatelet therapy of aspirin plus clopidogrel or prasugrel. A minimal number of PEDs were deployed, with coils inserted using a stent-jail technique, avoiding dense packing. A total of 46 aneurysms (43 patients; median dome size, 11.6 mm; median neck width, 6.3 mm) were treated with PED/coil. The median volume embolization ratio was 14.8%. The degree of angiographic filling at the 6-month and latest angiography showed complete occlusion in 60.5% (26/43) and 70.5% (31/44), respectively. Small (< 10 mm) aneurysms achieved a higher complete occlusion rate in the early period; a lower cumulative incidence of aneurysm occlusion was observed in large and giant (≥ 10 mm) aneurysms (P = .024). The median clinical follow-up was 22 months, and no aneurysm ruptures occurred. Favorable clinical outcomes were achieved, with permanent neurological morbidity of 4.7% and no mortality. PED/coil demonstrated a high angiographic occlusion rate at an early stage. Loosely packed coils are sufficient to obliterate aneurysms effectively., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Vasospasm, initial neurological damage, rebleeding, and periprocedural complications are associated prognostic factors for clinical outcomes after aneurysmal subarachnoid hemorrhage (SAH). In this study, factors related to delayed ischemic neurological deficit (DIND) are evaluated using data from our institute for the last 18 years. Data from 2001 to 2018 of patients with aneurysmal SAH who underwent surgical clipping (SC) or endovascular coiling (EC) within 7 days of onset were retrospectively analyzed. Cases of mortality within 5 days after treatment were excluded. Multivariate analysis was used to identify the risk factors for DIND. In total, 840 cases of SAH were assessed; among these cases, 384 (45.7%) and 456 (54.3%) were treated with SC and EC, respectively. The frequency of DIND in the EC group was significantly less than that in the SC group (11.8% vs. 17.7%; p = 0.016). In the results of multivariate analysis, internal carotid artery (ICA) aneurysm and hemorrhagic complications were the risk factors for DIND. Cilostazol administration and EC were significant factors for vasospasm prevention after aneurysmal SAH (odds ratio of ICA aneurysm: 1.59, hemorrhagic complications: 1.76, SC: 1.51, and cilostazol administration: 0.51, respectively). Cilostazol administration was also a significant factor in patients who were treated with EC. ICA aneurysm, treatment strategy, hemorrhagic complications, and cilostazol administration were associated with DIND. Oral administration of cilostazol and avoiding hemorrhagic complications were effective in DIND prevention. If both treatments are available for ruptured aneurysms, clinicians should choose EC on the basis of its ability to prevent DIND.

Background: Copolymer (Onyx) embolization is an effective treatment for dural arteriovenous fistula (dAVF), however, some dAVFs have multiple, high-flow feeding vessels, resulting in insufficient embolization. For the treatment of such patients, we have developed a novel flow-control technique, the 'damp-and-push technique'. The purpose of this study was to evaluate the technical efficiency and safety of this technique., Methods: Seven patients who had been diagnosed with intracranial dAVF were treated by transarterial Onyx embolization using the damp-and-push technique between 2016 and 2019. This technique was designed to reduce blood flow to the shunt site using a balloon catheter in the major feeding vessel other than the one injected with Onyx, leading to better Onyx penetration and enabling more controlled embolization of complex dAVFs. Retrospectively collected data were reviewed to assess the occlusion rates and clinical outcomes., Results: The dAVF was at a transverse sinus-sigmoid sinus junction in four patients, in the superior sagittal sinus in two, and in the tentorium in one. Five cases were Cognard type Ⅱb and two cases were Cognard type Ⅳ. All the patients were treated by transarterial Onyx injection via the main feeding vessel, combined with flow reduction in the other main feeding vessel using a balloon catheter. Complete occlusion was achieved in six patients and elimination of cerebral venous reflux was achieved in all the patients. There were no immediate or delayed post-interventional complications., Conclusions: Transarterial Onyx embolization of dAVF using the damp-and-push technique is safe and yields a high complete occlusion rate., Competing Interests: Declaration of Competing Interest The authors declare that there is no conflict of interest., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Background and Purpose: With the increasing use of the Pipeline Embolization Device for the treatment of aneurysms, predictors of clinical and angiographic outcomes are needed. This study aimed to identify predictors of incomplete occlusion at last angiographic follow-up., Materials and Methods: In our retrospective, single-center cohort study, 105 ICA aneurysms in 89 subjects were treated with Pipeline Embolization Devices. Patients were followed per standardized protocol. Clinical and angiographic outcomes were analyzed. We introduced a new morphologic classification based on the included angle of the parent artery against the neck location: outer convexity type (included angle,  <160°), inner convexity type (included angle,  >200°), and lateral wall type (160° ≤ included angle  ≤200°). This classification reflects the metal coverage rate and flow dynamics., Results: Imaging data were acquired in 95.3% of aneurysms persistent at 6 months. Complete occlusion was achieved in 70.5%, and incomplete occlusion, in 29.5% at last follow-up. Multivariable regression analysis revealed that 60 years of age or older (OR, 5.70; P  = .001), aneurysms with the branching artery from the dome (OR, 10.56; P  = .002), fusiform aneurysms (OR, 10.2; P  = .009), and outer convexity-type saccular aneurysms (versus inner convexity type: OR, 30.3; P  < .001; versus lateral wall type: OR, 9.71; P  = .001) were independently associated with a higher rate of incomplete occlusion at the last follow-up. No permanent neurologic deficits or rupture were observed in the follow-up period., Conclusions: The aneurysm neck located on the outer convexity is a new, incomplete occlusion predictor, joining older age, fusiform aneurysms, and aneurysms with the branching artery from the dome. No permanent neurologic deficits or rupture was observed in the follow-up, even with incomplete occlusion., (© 2021 by American Journal of Neuroradiology.)

Objective: The efficacy and safety of acute percutaneous transluminal angioplasty or stenting (PTA/PTAS) for vertebrobasilar artery occlusion with atherothrombotic brain infarction (ATBI) have not been confirmed despite the resistance to medical therapy alone. There are few reports about this disease and its treatment. Therefore, the treatment outcomes at our hospital were summarized to evaluate the efficacy and safety., Methods: This was a retrospective study of acute PTA/PTAS for vertebrobasilar artery occlusion due to atherosclerotic change in 19 consecutive patients with a modified Rankin Scale (mRS) score of 0-2 before stroke between March 2010 and December 2018. The factors related to prognosis were investigated. Outcomes were assessed at 90 days of follow-up., Results: Of 19 patients with acute vertebrobasilar artery occlusion treated by PTA/PTAS, 8 had good outcomes (mRS 0-2) and 11 had poor outcomes (mRS 3-6). There were no differences in the clinical or patient background except for the National Institutes of Health Stroke Scale (NIHSS) score between groups. The good outcome group had a lower NIHSS score than the poor outcome group (median: 9.5 vs 35, p <0.001). The Thrombolysis in Cerebral Ischemia (TICI) 2b-3 group had a slightly more favorable outcome than the TICI0-2a group (p = 0.10). There were no differences in outcome between PTA and PTAS groups (p = 0.65)., Conclusion: Reperfusion of the posterior circulation by PTA/PTAS may be necessary for a good outcome. Although acute stenting must be performed under careful observation, a stent can be placed when recurrence in the early phase is estimated with high probability., Competing Interests: Hirotoshi Imamura received rewards as lecture fees from Stryker Japan and Medtronic Japan. Nobuyuki Sakai received research funds from Terumo Corporation, and rewards as lecture fees from Biomedical Solutions, Johnson & Johnson, Medtronic Japan, Penumbra, Stryker Japan, and Terumo Corporation. The remaining authors declare no conflicts of interest regarding the publication of this article., (©2021 The Japanese Society for Neuroendovascular Therapy.)

Background: We experienced two cases of ischemic stroke resulting from carotid artery occlusion associated with acute type A aortic dissection (ATAAD), in which carotid artery stenting before the surgery for ATAAD resulted in good clinical outcomes. Case 1 description: A 63-year-old woman was hospitalized for conscious disturbance, right hemiparesis, and total aphasia. Computed tomography of the head showed no abnormal findings. Computed tomography angiography showed ATAAD and bilateral common carotid artery occlusion. Surgery was not indicated for ATAAD because of a poor prognosis of ischemic stroke. However, carotid artery stenting of the left common carotid artery occlusion was successfully performed, and her neurological findings improved. The patient underwent hemiarch replacement for ATAAD on the day after carotid artery stenting. Her final modified Rankin Scale was 1. Case 2 Description: A 57-year-old woman was hospitalized for mild left hemiparesis. Magnetic resonance imaging showed right watershed infarction and right common carotid artery occlusion. Computed tomography angiography showed ATAAD. After hospitalization, conscious disturbance appeared and left hemiparesis worsened. Ischemic stroke indicated a poor prognosis for revascularization by surgery for ATAAD. Thus, carotid artery stenting of the right common carotid artery occlusion was performed. The patient's neurological findings improved and she underwent hemiarch replacement for ATAAD at 19 days after carotid artery stenting. Her final modified Rankin Scale was 1., Conclusions: In the present cases, although ischemic stroke was serious and precluded surgical indication for ATAAD, carotid artery stenting before surgery for ATAAD resulted in good clinical outcomes. Performing carotid artery stenting before surgery for ATAAD is challenging but achievable, and is a valid treatment option depending on the individual cases.

Introduction: In our institute, most cases of carotid artery stenosis are treated by carotid artery stenting (CAS) with an open-cell stent and double-balloon protection, even if plaques are unstable. This study was performed to examine the outcome of CAS with an open-cell stent and double-balloon protection for unstable plaques., Methods: A total of 184 CAS procedures in our institute between October 2010 and February 2018 were assessed. Ultrasonography findings of low-echo plaques, plaque ulceration, or both were defined as unstable plaques. A plaque-to-muscle ratio (PMR) of >1.8 on T1-weighted black blood imaging using spin-echo was also defined as an unstable plaque. Seventy-four unstable plaques on ultrasonography and 86 unstable plaques evaluated by PMR were included. Open-cell stents and double-balloon protection (proximal balloon protection during lesion crossing and distal balloon protection after lesion crossing) were used in all cases., Results: On ultrasonography, perioperative asymptomatic thromboembolization was significantly more frequent in the unstable plaque group (39/74, 52.7%) than in the stable plaque group (41/110, 37.3%, p=0.0384). Asymptomatic thromboembolization was also significantly more frequent in the PMR >1.8 group (44/86, 51.2%) than in the PMR <1.8 group (36/98, 36.7%, p=0.0489). However, symptomatic thromboembolization was rare (n=5, 2.7%), and all of these patients had minor stroke. During the 4-year follow-up, the risk of ipsilateral stroke was 0.28% and 0.27% per year in patients with symptomatic and asymptomatic lesions, respectively., Conclusions: The outcomes of CAS with an open-cell stent and double-balloon protection are acceptable. This method is effective and safe, even if carotid artery stenosis comprises unstable plaques., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. No commercial re-use. See rights and permissions. Published by BMJ.)