Intraorbital Dural Arteriovenous Fistula Treated by Transarterial Embolization Using Onyx: A Case Report.

Objective: Intraorbital dural arteriovenous fistula (IO-dAVF) is a rare condition, and treatment options vary from case to case. We report a case of transarterial embolization (TAE) for IO-dAVF. Case Presentation: A 62-year-old male complained of gradually worsening pain, hyperemia, and visual impairment in the right eye. He did not exhibit diplopia or exophthalmos. Cerebral angiography revealed an arteriovenous fistula in the right orbit. The feeding arteries were the ophthalmic artery (OphA) and the artery of the superior orbital fissure (ASOF), with the superior ophthalmic vein (SOV) as the main draining vein. The venous pathway from the SOV was not clearly visible, and considering the risk of blindness with TAE from the OphA, TAE from the ASOF was performed. Onyx 18 was selected as the liquid embolic material and injected through a microcatheter placed in the internal maxillary artery. Occlusion up to the SOV was achieved, and the shunt flow completely disappeared. Normal blood flow in the OphA was maintained, hyperemia improved, and no complications were observed. Conclusion: In cases of IO-dAVF, when transvenous embolization is difficult to perform, TAE using Onyx from the vessel of the external carotid artery system may be preferred over OphA.

Novel use of a closed-tip stent retriever to prevent distal embolism in the posterior circulation: illustrative case.

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.

Treatment Results of Carotid Artery Stenting with an Open-Cell Stent: Analysis of 734 Consecutive Cases at a Single Center.

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.

Clinical evaluation of mechanical thrombectomy for patients with posterior circulation occlusion: A retrospective study.

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.

Pipeline embolization device dynamics: prediction of incomplete occlusion by elongation from nominal length.

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.

First-in-human trial of Center Wire for neuroendovascular therapy to avoid guidewire-related complications.

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.

First-in-human trial of Stabilizer device in neuroendovascular therapy.

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.

PulseRider-assisted coil embolization for an unruptured internal carotid artery-persistent primitive trigeminal artery aneurysm.

A persistent primitive trigeminal artery (PPTA) is a vessel remnant of carotid-vertebrobasilar anastomosis. The aneurysm at the bifurcation of the internal carotid artery (ICA) and PPTA tends to have a broad neck with the branch incorporated into the sac. Because PPTA supplies to the posterior circulation and branches off direct pontine perforators, PPTA preservation should always be considered when treating PPTA aneurysms to avoid ischemic complications.We report a case of the wide-neck ICA-PPTA aneurysm successfully treated with the PulseRider-assisted coil embolization, resulting in complete occlusion with PPTA patency. Relevant anatomy and endovascular strategy of the PPTA aneurysms are discussed.

Comparison of Symptomatic Vasospasm after Surgical Clipping and Endovascular Coiling.

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.

Pipeline flow diversion with adjunctive coil embolization for internal carotid artery aneurysms following an intradural component: results in 46 consecutive aneurysms from a Japanese single-center experience.

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.

A Damp-and-Push Technique for the Copolymer (Onyx) Embolization of Dural Arteriovenous Fistula.

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.

Initial Results of Percutaneous Transluminal Angioplasty/Stenting for Vertebrobasilar Occlusion due to Atherothrombotic Disease during Acute Phase.

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.

Carotid artery stenting before surgery for carotid artery occlusion associated with acute type A aortic dissection: Two case reports.

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.

Deep Learning-Derived High-Level Neuroimaging Features Predict Clinical Outcomes for Large Vessel Occlusion.

Background and Purpose- For patients with large vessel occlusion, neuroimaging biomarkers that evaluate the changes in brain tissue are important for determining the indications for mechanical thrombectomy. In this study, we applied deep learning to derive imaging features from pretreatment diffusion-weighted image data and evaluated the ability of these features in predicting clinical outcomes for patients with large vessel occlusion. Methods- This multicenter retrospective study included patients with anterior circulation large vessel occlusion treated with mechanical thrombectomy between 2013 and 2018. We designed a 2-output deep learning model based on convolutional neural networks (the convolutional neural network model). This model employed encoder-decoder architecture for the ischemic lesion segmentation, which automatically extracted high-level feature maps in its middle layers, and used its information to predict the clinical outcome. Its performance was internally validated with 5-fold cross-validation, externally validated, and the results compared with those from the standard neuroimaging biomarkers Alberta Stroke Program Early CT Score and ischemic core volume. The prediction target was a good clinical outcome, defined as a modified Rankin Scale score at 90-day follow-up of 0 to 2. Results- The derivation cohort included 250 patients, and the validation cohort included 74 patients. The convolutional neural network model showed the highest area under the receiver operating characteristic curve: 0.81±0.06 compared with 0.63±0.05 and 0.64±0.05 for the Alberta Stroke Program Early CT Score and ischemic core volume models, respectively. In the external validation, the area under the curve for the convolutional neural network model was significantly superior to those for the other 2 models. Conclusions- Compared with the standard neuroimaging biomarkers, our deep learning model derived a greater amount of prognostic information from pretreatment neuroimaging data. Although a confirmatory prospective evaluation is needed, the high-level imaging features derived by deep learning may offer an effective prognostic imaging biomarker.

Outcomes of Endovascular Therapy versus Microsurgical Treatment for Aneurysmal Subarachnoid Hemorrhage in Patients ≥70 Years of Age.

Purpose: This retrospective research aimed to compare the efficacy of endovascular therapy (EVT) versus microsurgical treatment (MST) for elderly patients with aneurysmal subarachnoid hemorrhage (aSAH). Methods: Elderly (>70 years) patients with aSAH who underwent aneurysm obliteration during 2007-2017 were selected from our hospital database and enrolled in this retrospective study. We reviewed each patient's background, the severity of the aSAH, and aneurysmal characteristics that compelled EVT or microsurgery treatment and then compared the two treatment groups. A favorable primary outcome was defined by a modified Rankin scale (mRS) score of 0-3 at hospital discharge. The 78 patients formed two cohorts (39 patients each) based on their propensity scores for EVT or MST. We estimated the adjusted odds ratio, followed by a sensitivity analysis of the original 201 patients (118 with EVT and 83 with MST). Results: In the propensity score-matched cohorts, favorable outcomes were observed in 33.3% and 7.7% of patients in the EVT and MST groups, respectively (p = 0.01). Results of the sensitivity analysis were similar to the main results. Conclusion: The clinical outcomes for the elderly aSAH patients were better in the EVT group than in MST group.

A Case of Subarachnoid Hemorrhage with Dissecting Aneurysm of the Anterior Choroidal Artery.

Objective: Dissecting aneurysms of the anterior choroidal artery (AchoA) are extremely rare, with only a few reported cases. Herein, we report an extremely rare case of subarachnoid hemorrhage with dissecting aneurysm of the AchoA. Case Presentation: A 68-year-old man was hospitalized for sudden onset of headache, progressive consciousness disorder, and right hemiparesis. He had a prior medical history of systemic lupus erythematosus (SLE), and was taking prednisolone (50 mg/day) for 15 months. CT showed subarachnoid hemorrhage in the left side of the basal cistern and Sylvian fissure. Left internal carotid artery (ICA) angiography revealed a fusiform aneurysm of the AchoA. He was diagnosed with a ruptured dissecting aneurysm of the AchoA because the shape of aneurysm was fusiform and there was laminar flow inside the aneurysm. Parent artery occlusion (PAO) was performed to prevent re-hemorrhage on the day of onset. Although ventricular drainage for acute hydrocephalus was performed after AchoA occlusion, his consciousness disorder did not improve. Postoperative angiography at 1-week recovery from the procedure revealed disappearance of the AchoA, including the dissecting aneurysm. However, he died following septic shock caused by pneumonia at 1 month after the procedure. Conclusion: We report an extremely rare case of subarachnoid hemorrhage with a dissecting aneurysm of the AchoA. Vasculitis caused by SLE and a vulnerability of the vessel wall following chronic steroid use are potential causes of the dissecting aneurysm of the AchoA.

Safety and efficacy of an open-cell stent and double-balloon protection for unstable plaques: analysis of 184 consecutive carotid artery stentings.

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.

MicroRNA-Based Separation of Cortico-Fugal Projection Neuron-Like Cells Derived From Embryonic Stem Cells.

The purification of pluripotent stem cell-derived cortico-fugal projection neurons (PSC-CFuPNs) is useful for disease modeling and cell therapies related to the dysfunction of cortical motor neurons, such as amyotrophic lateral sclerosis (ALS) or stroke. However, no CFuPN-specific surface markers for the purification are known. Recently, microRNAs (miRNAs) have been reported as alternatives to surface markers. Here, we investigated this possibility by applying the miRNA switch, an mRNA technology, to enrich PSC-CFuPNs. An array study of miRNAs in mouse fetal brain tissue revealed that CFuPNs highly express miRNA-124-3p at E14.5 and E16.5. In response, we designed a miRNA switched that responds to miRNA-124-3p and applied it to mouse embryonic stem cell (ESC)-derived cortical neurons. Flow cytometry and quantitative polymerase chain reaction (qPCR) analyses showed the miRNA-124-3p switch enriched CFuPN-like cells from this population. Immunocytechemical analysis confirmed vGlut1/Emx1/Bcl11b triple positive CFuPN-like cells were increased from 6.5 to 42%. Thus, our miRNA-124-3p switch can uniquely enrich live CFuPN-like cells from mouse ESC-derived cortical neurons.

[Treatment Strategies for Unruptured Multiple Intracranial Aneurysms].

OBJECTIVE: Unruptured aneurysms are often discovered incidentally on MRI. In some patients, multiple aneurysms cannot be treated with only craniotomy or endovascular surgery. When both craniotomy and endovascular surgery are deemed necessary, craniotomy is generally performed first because of the use of antiplatelet agents involved, followed by endovascular surgery several months later. However, no clear criteria for this treatment policy have been elicited. We investigated therapeutic outcomes in patients with aneurysms treated by craniotomy followed by endovascular surgery at our hospital. PATIENTS AND METHODS: This was a retrospective study including patients undergoing craniotomy clipping of one or more unruptured aneurysms at one site and endovascular surgery for those at a different site, between January 2012 and May 2018 in our hospital. The types of treatment, interval between treatments, complications, and other factors were analyzed. RESULTS: This study included 22 patients who underwent a total of 25 craniotomies and 23 endovascular surgeries. The mean time from final craniotomy to initial endovascular surgery was 118 days. Although treatment-related complications occurred in three patients, they were not associated with the time interval between craniotomy and endovascular surgery or the timing of the start of the antiplatelet therapy. CONCLUSIONS: The treatment was successful and was carried out safely and appropriately by first performing the craniotomy, followed by a set interval of time before starting the antiplatelet therapy, and then performing the endovascular surgery. Further studies analyzing more cases are required to establish the criteria better, such as the appropriate interval time between treatments.

Predicting Clinical Outcomes of Large Vessel Occlusion Before Mechanical Thrombectomy Using Machine Learning.

Background and Purpose- The clinical course of acute ischemic stroke with large vessel occlusion (LVO) is a multifactorial process with various prognostic factors. We aimed to model this process with machine learning and predict the long-term clinical outcome of LVO before endovascular treatment and to compare our method with previously developed pretreatment scoring methods. Methods- The derivation cohort included 387 LVO patients, and the external validation cohort included 115 LVO patients with anterior circulation who were treated with mechanical thrombectomy. The statistical model with logistic regression without regularization and machine learning algorithms, such as regularized logistic regression, linear support vector machine, and random forest, were used to predict good clinical outcome (modified Rankin Scale score of 0-2 at 90 days) with standard and multiple pretreatment clinical variables. Five previously reported pretreatment scoring methods (the Pittsburgh Response to Endovascular Therapy score, the Stroke Prognostication Using Age and National Institutes of Health Stroke Scale index, the Totaled Health Risks in Vascular Events score, the Houston Intra-Arterial Therapy score, and the Houston Intra-Arterial Therapy 2 score) were compared with these models for the area under the receiver operating characteristic curve. Results- The area under the receiver operating characteristic curve of random forest, which was the worst among the machine learning algorithms, was significantly higher than those of the standard statistical model and the best model among the previously reported pretreatment scoring methods in the derivation (the area under the receiver operating characteristic curve were 0.85±0.07 for random forest, 0.78±0.08 for logistic regression without regularization, and 0.77±0.09 for Stroke Prognostication using Age and National Institutes of Health Stroke Scale) and validation cohorts (the area under the receiver operating characteristic curve were 0.87±0.01 for random forest, 0.56±0.07 for logistic regression without regularization, and 0.83±0.00 for Pittsburgh Response to Endovascular Therapy). Conclusions- Machine learning methods with multiple pretreatment clinical variables can predict clinical outcomes of patients with anterior circulation LVO who undergo mechanical thrombectomy more accurately than previously developed pretreatment scoring methods.