山田 健嗣

BACKGROUND AND OBJECTIVES: Although intraprocedural rupture (IPR) is rare, it is a devastating complication of endovascular treatment (EVT) for intracranial aneurysms. Very few studies have been conducted on IPR, and the safety and efficacy of management techniques of IPR have not been investigated. METHODS: Patients who experienced IPR during EVT between 2013 and 2022 were enrolled from a multicenter observational registry. We examined the safety and efficacy of the management of IPR using imaging markers, including increased hemorrhage and ischemic lesions, which were evaluated using postoperative computed tomography and diffusion-weighted imaging, respectively. RESULTS: Of the 3269 EVTs for intracranial aneurysms, 74 patients who experienced IPR (2.26%) were analyzed. Fifty-five patients (3.36%) experienced IPR among 1636 EVT cases for ruptured aneurysms. Multivariate analysis revealed that increased hemorrhage was significantly associated with poor outcomes (odds ratio [OR], 6.37 [95% CI, 1.00-40.51], P = .050), whereas ischemic lesions were not. Regarding management techniques of IPR, antihypertensive medication use was significantly associated with increased hemorrhage (OR, 14.16 [95% CI, 2.35-85.34], P = .004). Heparin reversal was an independent factor for ischemic lesions (OR, 8.92 [95% CI, 1.54-51.58], P = .014). CONCLUSION: Although the setting of IPR may be miscellaneous, and optimal management varies depending on individual cases, heparin reversal might be associated with ischemic complications, and its role in the successful hemostasis in IPR during EVT for ruptured aneurysms remains unclear.

BACKGROUND: Endovascular treatment has become the preferred approach for managing unruptured cerebral aneurysms, with simple and balloon-assisted coil embolization as the standard first-line therapy. However, recanalization after coil embolization remains a major clinical concern. This study aimed to evaluate the predictive factors for recanalization using time-of-flight magnetic resonance (TOF-MR) angiography. METHODS: This retrospective multicenter study analyzed data from 241 patients with unruptured cerebral aneurysms who underwent coil embolization at 5 stroke centers. Aneurysms were evaluated using TOF-MR angiography within 7 days postprocedure and at follow-up. The study investigated the role of aneurysm characteristics and the Postoperative TOF-MR Angiography (PTMA) classification in predicting recanalization. RESULTS: Of the 241 aneurysms analyzed, 79 (32.7%) exhibited recanalization, and 15 (6.2%) required retreatment. Aneurysms with a maximum diameter of ≥10 mm were associated with a higher risk of recanalization (odds ratio, 3.27; 95% confidence interval (CI), 1.38-7.75; P < 0.01). The PTMA classification, which indicated incomplete occlusion (small residual neck/residual neck/partial occlusion), also showed a significant association with recanalization (odds ratio, 4.82; 95% confidence interval, 2.17-10.7; P < 0.01). The modified Raymond-Roy classification (Class IIIb) also contributed to the prediction of recanalization (odds ratio, 3.09; 95% confidence interval, 1.50-6.38; P < 0.01). CONCLUSIONS: Aneurysm size, the modified Raymond-Roy classification, and PTMA classification within 7 days of coil embolization were significant predictors of recanalization. This study suggests that TOF-MR angiography may be accurate, and that PTMA classification may serve as an appropriate predictor of aneurysm recanalization. Further prospective studies with larger cohorts are required to validate our findings.

OBJECTIVE: Dural arteriovenous fistulas (dAVFs) in the paracavernous sinus of the sphenoid wing often present challenges for transvenous access because of their complex venous drainage patterns. Herein, we report the successful diagnosis and treatment of a greater sphenoid wing dAVF using a percutaneous transvenous approach via the Labbé vein. CASE PRESENTATION: A 48-year-old woman presented with tinnitus and was diagnosed with a greater sphenoid wing dAVF. The dAVF was fed by multiple meningeal arteries from the accessory meningeal artery. Shunted blood drained retrogradely into the superficial middle cerebral vein (SMCV) and bilateral inferior petrosal sinus (IPS) via the cavernous sinus (CS). Although communication was observed between the shunt pouch and the lateral part of the CS, the tortuous and narrow nature of this connection suggests difficulty in accessing the shunt pouch via the IPS. Conversely, the SMCV, which served as the primary outflow pathway, was adequately connected to the vein of Labbé with minimal difficulty, facilitating the passage of the microcatheter. The percutaneous transvenous approach via the Labbé vein successfully reached the SMCV and achieved complete obliteration with selective transvenous embolization (TVE) using coils. The symptoms of the patient improved postoperatively, and the patient was discharged without complications. CONCLUSION: Greater sphenoid wing dAVFs often rely on the SMCV as the major drainage route, making venous approaches challenging. The route via the vein of Labbé through the cortical veins to reach the SMCV proved to be a valuable access route for TVE of greater sphenoid wing dAVFs.

OBJECTIVES: Distal anterior cerebral artery (DACA) aneurysms account for 1%-9% of all intracranial aneurysms. Microsurgical treatment is generally preferred for DACA aneurysms; however, it presents challenges owing to the anatomical complexities. Advances in neuro-interventional techniques have yielded promising results. This study aims to compare the clinical outcomes of DACA aneurysms treated with microsurgery and endovascular treatment (EVT) to elucidate the efficacy of EVT. MATERIALS AND METHODS: A multicenter observational registry comprising 16 stroke centers was utilized for this study. Data was retrospectively and prospectively analyzed from 166 patients with DACA aneurysms in our database, which included 4,552 consecutive patients with ruptured or unruptured intracranial aneurysms who underwent microsurgical or endovascular treatment between January 2013 and December 2021. RESULTS: Surgical clipping was performed in 115 patients, and 51 underwent coil embolization. The median follow-up duration was 15.3 months. No significant differences were observed in patient characteristics between the two treatment modalities. There were no differences in complication-related morbidity between the microsurgical treatment and EVT groups in either unruptured (10.5% vs. 9.1%, p=1.00) or ruptured aneurysms (5.2% vs. 6.9%, p=0.66). Coil embolization resulted in higher recurrence and retreatment rates than surgical clipping did, especially for ruptured aneurysms (2.6% vs. 27.6%, p<0.01). CONCLUSIONS: Endovascular treatment is an alternative to microsurgery for DACA aneurysms especially in unruptured cases or the patients who have difficulty undergoing craniotomy due to their general condition, albeit with considerations for higher recurrence and retreatment rates, particularly in ruptured cases. Close follow-up is crucial for the effective management of these challenges. Further studies are needed to refine the treatment strategies for DACA aneurysms.

PURPOSE: The quick establishment of adequate vascular access is essential for the technical success of mechanical thrombectomy (MT). Focusing on shifts in aortic arch geometry and aging-related changes, we propose an imaging parameter for predicting access difficulty using chest CT. METHODS: Patients with acute anterior circulation large-vessel occlusion who underwent MT from April 2020 to September 2021 were included in this retrospective multicenter observational study. The distance from the sternum to the ascending aorta (S-AAD) was defined as the surrogate marker of access difficulty. Access was defined as difficult when the time from femoral sheath placement to guiding catheter induction (guiding time: GT) ≥ 30 minutes, and the patients were dichotomized into groups with short GT (sGT: GT < 30 min) and long GT (lGT: GT ≥ 30 min). RESULTS: One hundred fifteen patients were included. There were 12 patients (10.4 %) in lGT group. The median (IQR) S-AAD was 11.9 mm (6.3, 18.3 mm) in sGT group and 6.6 mm (4.0, 10.3 mm) in lGT group, and a significant difference in S-AAD was observed (P = 0.026). In multivariate analyses, dyslipidemia and S-AAD < 5 mm were significantly associated with difficult access (OR, 5.938 [95 % CI, 1.468, 24.022], P = 0.012 for dyslipidemia; OR, 5.147 [95 % CI, 1.267, 20.917], P = 0.022 for S-AAD < 5 mm). CONCLUSION: S-AAD is a simple and reliable imaging parameter to predict access difficulty. This parameter may be helpful in selecting the appropriate devices and access routes in preinterventional practice.

OBJECTIVE: Effective thrombectomies in the posterior circulation remain controversial. Previous reports have demonstrated the superiority of contact aspiration in anterior circulation. Aspiration catheters and stent retrievers are often used alone on a global scale, while combined techniques are commonly used in Japan. This study evaluated the effect of first-line contact aspiration with other strategies for the treatment of basilar artery occlusion. METHODS: The primary outcome was the frequency of the first-pass effect, and the secondary outcome was the time from puncture to the first-pass effect. A multicenter observational registry including 16 Japanese stroke centers was used. Between December 2013 and February 2021, enrolled patients underwent endovascular thrombectomy for basilar artery occlusion. The efficacy of contact aspiration compared to other methods (including stent retrievers and combined techniques) was evaluated. RESULTS: Eighty-four patients were included, all of whom had achieved effective recanalization. Twenty-six patients were treated with contact aspiration, 13 with combined technique, and 45 with stent retrievers. The two groups: contact aspiration and non-contact aspiration, had different backgrounds. Both had similar frequencies of effective recanalization and first-pass effects. The contact aspiration group experienced better functional outcomes without statistical significance, while this strategy was significantly associated with a shorter puncture-to-recanalization time (38 vs. 55 minutes, P=0.036). In particular, in the 55 patients with the first-pass effect, multivariate Cox proportional hazard analysis showed that contact aspiration was significantly associated with a shorter time from puncture to first-pass effect, independent of age and etiology of large-artery atherosclerosis (hazard ratio 2.02, 95% confidence intervals 1.10-3.69, P=0.023). CONCLUSION: This study suggested that contact aspiration for basilar artery occlusion may shorten the puncture-to-first-pass effect, compared to stent retrievers and combined techniques.

INTRODUCTION: Hybrid emergency room systems (HERSs) have shown promise for the management of severe trauma by reducing mortality. However, the effectiveness of HERSs in the treatment of acute ischemic stroke (AIS) remains unclear. This study aimed to evaluate the impact of HERSs on treatment duration and neurological outcomes in patients with AIS undergoing endovascular therapy. MATERIALS AND METHODS: This single-center retrospective study included 83 patients with AIS who were directly transported to our emergency department and underwent endovascular treatment between June 2017 and December 2023. Patients were divided into the HERS and conventional groups based on the utilization of HERSs. The primary outcome was the proportion of patients achieving a favorable neurological outcome (modified Rankin Scale score 0-2) at 30 days. The secondary outcomes included door-to-puncture and door-to-recanalization times. Univariate analysis was performed using the Mann-Whitney U test for continuous variables and the chi-squared test or Fisher's exact test for categorical variables, as appropriate. RESULTS: Of the 83 eligible patients, 50 (60.2%) were assigned to the HERS group and 33 (39.8%) to the conventional group. The median door-to-puncture time was significantly shorter in the HERS group than in the conventional group (99.5 vs. 131 min; p = 0.001). Similarly, the median door-to-recanalization time was significantly shorter in the HERS group (162.5 vs. 201.5 min, p = 0.018). Favorable neurological outcomes were achieved in 16/50 (32.0%) patients in the HERS group and 6/33 (18.2%) in the conventional group. The HERS and conventional groups showed no significant difference in the proportion of patients achieving favorable neurological outcomes (p = 0.21). CONCLUSION: Implementation of the HERS significantly reduced the door-to-puncture and door-to-recanalization times in patients with AIS undergoing endovascular therapy. Despite these reductions in treatment duration, no significant improvement in neurological outcomes was observed. Further research is required to optimize patient selection and treatment strategies to maximize the benefits of the HERS in AIS management.

PURPOSE: We aimed to investigate the impact of baseline infarct area and collateral status (CS), which are imaging predictors of clinical outcome following stroke, after endovascular treatment (EVT) in MRI-selected patients with acute basilar artery occlusion (BAO). METHODS: Patients with acute BAO who underwent EVT within 24 h after stroke from December 2013 to February 2021 were included in this retrospective, multicenter, observational study. The baseline infarct area was evaluated by the posterior circulation of Acute Stroke Prognosis Early Computed Tomography Score (pc-ASPECTS) using diffuse-weighted imaging (DWI), and CS was assessed by measuring the computed tomography angiography of the basilar artery (BATMAN) score and the posterior circulation collateral score (PC-CS) using magnetic resonance angiography (MRA). A Good outcome was defined as a modified Rankin scale score ≤ 3 at 3 months. For each imaging predictor, a multivariate logistic regression analysis was performed to evaluate its impact on good outcomes. RESULTS: A total of 86 patients were analyzed, and 37 (43.0%) had a good outcome. The latter showed significantly higher pc-ASPECTS than those without good outcomes. In multivariate analyses, a pc-ASPECTS ≥ 7 was significantly associated with good outcomes (OR, 2.98 [95% CI, 1.10-8.13], P = 0.032), while PC-CS ≥ 4 (OR, 2.49 [95% CI, 0.92-6.74], P = 0.073) and BATMAN score ≥ 5 (OR, 1.51 [95% CI, 0.58-3.98], P = 0.401) were not. CONCLUSIONS: In MRI-selected patients with acute BAO, pc-ASPECTS on DWI was an independent predictor of clinical outcomes after EVT, while the MRA-based CS assessments were not.

BACKGROUND AND PURPOSE: To measure the magnitude of the effect of the infarct location measured using the posterior circulation Alberta Stroke Program Early Computed Tomographic Score (pc-ASPECTS) on the functional outcome at 90 days in patients with basilar artery (BA) occlusion undergoing endovascular therapy (EVT). METHODS: Of the acute ischemic stroke patients undergoing EVT for acute posterior circulation large vessel occlusion enrolled in the multicenter observational registry from December 2013 to February 2021, patients with BA occlusion were included. A favorable outcome was defined as achieving a modified Rankin Scale score of 0-3 at 90 days. The effect of pc-ASPECTS including the distribution on favorable outcomes was evaluated. RESULTS: One hundred patients were analyzed. Fifty-one patients (51%) achieved favorable outcome. Patients achieving a favorable outcome were younger, had a lower National Institutes of Health Stroke Scale score before EVT, and had a higher pc-ASPECTS before EVT than those not achieving a favorable outcome. Multivariable logistic analysis showed a significant association between higher pc-ASPECTS and a favorable outcome (odds ratio [OR] 1.24; 95% confidence interval [CI] 1.02-1.52; P = 0.028). Considering the infarct location, bilateral cerebellar infarction was significantly associated with a lower frequency of favorable outcomes than those without cerebellar infarction (OR 0.16; 95% CI 0.04-0.51; P = 0.002). CONCLUSIONS: A higher pc-ASPECTS before EVT could be a predictor of a favorable outcome after EVT for BA occlusion. In particular, the presence of bilateral cerebellar infarction before EVT was significantly associated with a lower likelihood of a favorable outcome.

BACKGROUND: Postoperative cerebral embolic stroke is a serious complication of pulmonary lobectomy, occurring in 1.1% of patients undergoing lobectomy through video-assisted thoracoscopic surgery (VATS). The mechanism of this complication is thought to be embolic stroke caused by thrombus formed due to stagnation in the pulmonary vein stump after VATS lobectomy. There have been few reports demonstrating the utility of endovascular treatment (EVT) for cerebral embolic stroke after VATS lobectomy. CASE DESCRIPTION: In our case series, cerebral embolic stroke occurred after VATS pulmonary lobectomy for lung cancer, including the left upper lobe in three cases and the right lobe in one. The median duration of ischemic stroke after VATS was 4.5 days (interquartile range, 2-9 days). The median time from stroke onset to puncture was 130 min. Successful recanalization was achieved in all cases, and two patients achieved favorable clinical outcomes (modified Rankin scale, 0-2). CONCLUSION: We report a case series of four patients who underwent EVT for acute embolic stroke after VATS lobectomy for lung cancer. EVT is considered a reasonable and feasible therapeutic option for this condition.

This study aimed to analyze the hemodynamic features of the offending artery at sites of neurovascular compression (NVC) using computational fluid dynamics (CFD). A total of 23 patients who underwent microvascular decompression (MVD) for primary trigeminal neuralgia (TN) between January 2015 and December 2016 were enrolled in this study. The compressing vessel at the NVC site was identified microsurgically in all cases, and patients were divided into two groups based on the intraoperative findings: (1) the arterial NVC group and (2) the non-arterial NVC control group. A 3D surface model of the structures surrounding the NVC was created using preoperative magnetic resonance imaging (MRI), and CFD analysis was performed for the target artery. In addition to standard parameters, such as the wall shear stress (WSS), flow velocity, and pressure, we calculated the WSS ratio (WSSR) by dividing the WSS at the NVC by the mean WSS of the target. Arterial compression was observed intraoperatively in 13 patients. The mean WSSR of the arterial NVC group was significantly higher than that of the control group (2.36 ± 1.00 vs. 1.18 ± 0.73, P <0.05). There were no significant intergroup differences in the other calculated parameters. High WSSR, which indicates elevated WSS at the sites of NVC, was identified as a unique parameter of arterial compression that may contribute to TN. CFD could be a useful clinical tool in determining the target of MVD under preoperative conditions.