田邉 淳

It is impossible to predict underlying anomalies in acute large vessel occlusion and it could be a problem when performing mechanical thrombectomy (MT). We report a case of MT for occlusion of the fenestrated middle cerebral artery (MCA) M1 segment. A 49-year-old woman presented to our hospital with dysarthria and left hemiparesis. Acute ischemic stroke due to right occluded MCA was diagnosed. During performing emergent MT, a part of the M1 segment was revealed to be slit-shaped by digital subtraction angiography, suggesting a fenestrated MCA. The aspiration catheter could not be advanced through the narrow limb of the fenestration, and the distal thrombus was retrieved using a stent retriever, additionally. Postoperatively, the patient's symptoms improved without complications. When occlusion of the fenestrated MCA is suspected, it is necessary to consider converting the strategy from an aspiration catheter alone to the combined use of a stent retriever.

PURPOSE: Prasugrel is not approved for patients treated with flow diverters, which have a high metal coverage ratio. However, robust antiplatelet therapy with prasugrel may prevent thromboembolic complications. We administered prasugrel and aspirin to all patients treated with flow diverters and reported the safety of the antiplatelet therapy regimen. METHODS: This retrospective, single-center study evaluated the angiographic and clinical data of consecutive patients treated with flow diverters for cerebral unruptured aneurysms between June 2020 and May 2022. All patients received dual antiplatelet therapy, including prasugrel and aspirin. The administration of prasugrel ended 3 or 6 months after the procedure, whereas aspirin use continued for at least 12 months. Periprocedural complications (< 30 days post-procedure) and delayed complications (> 30 days post-procedure) were recorded. RESULTS: During the study period, 120 unruptured aneurysms were treated with flow diverters in 110 patients. All patients, except one, survived longer than 12 months after the procedure. The rate of thromboembolic complications was 6.4%, and more than half of the patients had transient symptoms; one (0.9%) had a major ischemic stroke. One patient (0.9%) each had an asymptomatic, small subarachnoid hemorrhage and significant hemorrhagic complications with melena. The rate of permanent neurological deficits was 1.8%, and the mortality rate was 0.9%. CONCLUSIONS: Dual antiplatelet therapy comprising routine use of prasugrel and aspirin for flow diverter-implanted patients possibly contributed to a low rate of thromboembolic complications and low risk of hemorrhagic complications.

PURPOSE: Optimal size selection is important for successful Woven EndoBridge (WEB) treatment. Conventional recommendations for WEB sizing based on aneurysm width and height sometimes require device exchange. We aimed to design a novel volume-based parameter, the ideal WEB-aneurysm volume (iWAVe) ratio, for optimal WEB sizing. METHODS: Consecutive patients who underwent WEB treatment for wide-neck bifurcation aneurysms between January 2021 and May 2022 were retrospectively reviewed. Aneurysm volume was automatically calculated using software. We measured the aneurysm volume based on the expected position of the device within the aneurysm. The WAVe ratio was defined as the ratio of the aneurysm volume to WEB volume. We dichotomized aneurysms treated with a successful sizing or unsuccessful sizing for WEB (successful group and unsuccessful group, respectively). RESULTS: Thirty-five patients were eligible for study enrollment. Ten patients (28.6%) needed to exchange the WEB on the first attempt and required another WEB on the second attempt resulting in deployment success. Hence, 35 aneurysms were in the successful group and 10 were in the unsuccessful group. The median WAVe ratio was 1.0 (range 0.76-1.31) in the successful group and 1.27 (0.58-1.89) in the unsuccessful group. Using logistic regression, iWAVe ratio was from 0.90-1.16 to secure a >80% probability of success by the 95% lower confidence limit. The sensitivity and specificity of the iWAVe ratio for optimal size selection on the first attempt were 0.60 and 1.00, respectively. CONCLUSION: Decision-making based on aneurysm width and the iWAVe ratio could promote optimal WEB sizing.

OBJECTIVE: This retrospective study aimed to investigate factors associated with inhibition of early aneurysm obliteration after flow diverter (FD) treatment. We also created the early obliteration inhibition (EOI) score for pre-operative evaluation. METHODS: We examined 110 cerebral aneurysms in 104 patients who underwent FD treatment. The following parameters were investigated: age, sex, symptoms, aneurysm location and type, maximum aneurysm diameter, parent vessel diameter, neck diameter, and dome-neck ratio. We also noted aneurysm location relative to the curvature of the parent artery and any branches arising from the aneurysm dome. Procedural factors such as FD diameter and length, number of FDs placed, type of FD, and use of adjunctive coiling were also investigated. Aneurysm obliteration was evaluated using digital subtraction angiography 3 months after the procedure. Adequate obliteration was defined as grade C or D on the O'Kelly-Marotta scale. RESULTS: The following factors inhibited early obliteration: 1) extradural location, 2) saccular aneurysm, 3) aneurysm neck located at the outer convexity of the parent artery, and 4) arterial branch arising from the aneurysm dome. Odds ratios were used to create an EOI score. Receiver operating characteristic curve analysis showed that the optimal cut-off EOI score for adequate obliteration was 1.5 (area under the curve, 0.81; 95% confidence interval, 0.73-0.9; sensitivity, 0.9; specificity, 0.57). CONCLUSION: The EOI score, which is based on factors that inhibit early obliteration, may predict early treatment outcomes of FD placement.

<jats:sec xml:lang="en"> <jats:title>Background</jats:title> <jats:p xml:lang="en">Reperfusion therapy for acute ischemic stroke efficacy is highly time dependent; therefore, stroke centers are required to further reduce the delays from hospital arrival to treatment efficiently. We developed a visual task management application, Task Calculation Stroke (Task Calc. Stroke: TCS), to facilitate hospital acute ischemic stroke treatment by supporting parallel staff task completion. We evaluated TCS for the reduction of reperfusion therapy delays and improvement of clinical outcomes.</jats:p> </jats:sec> <jats:sec xml:lang="en"> <jats:title>Methods</jats:title> <jats:p xml:lang="en">In this multicenter cohort study, patients were directly admitted to 4 comprehensive stroke centers in Japan and given intravenous tissue plasminogen activator and/or mechanical thrombectomy from June 2018 to December 2020. The research team visited each facility and instructed the staff on TCS use for acute ischemic stroke (training stage), after which the staff used TCS independently (TCS stage). We then compared door‐to‐needle time for intravenous tissue plasminogen activator, door‐to‐puncture time for mechanical thrombectomy, and clinical outcomes at discharge according to the modified Rankin Scale among patients treated before training (original stage), during the training stage, or the TCS stage.</jats:p> </jats:sec> <jats:sec xml:lang="en"> <jats:title>Results</jats:title> <jats:p xml:lang="en"> During the study period, 316 patients with acute ischemic stroke received reperfusion therapy; of these, 246 received intravenous tissue plasminogen activator and 162 mechanical thrombectomy (including 92 receiving both the treatments). The mean door‐to‐needle time was significantly reduced from 58.0 minutes in the original stage to 54.6 minutes in the training stage ( <jats:italic>P</jats:italic> =0.049) and 47.8 minutes in the TCS stage ( <jats:italic>P</jats:italic> &lt;0.001). The door‐to‐puncture time did not change during the training stage; however, in the TCS stage, it significantly reduced from 93.8 minutes in the original stage to 88.5 minutes ( <jats:italic>P</jats:italic> =0.004). The distribution of modified Rankin Scale scores at discharge significantly shifted favorably at the TCS stage ( <jats:italic>P</jats:italic> =0.003). </jats:p> </jats:sec> <jats:sec xml:lang="en"> <jats:title>Conclusion</jats:title> <jats:p xml:lang="en">In this study, TCS application could reduce workflow time for reperfusion therapy and might have led to improved clinical outcomes.</jats:p> </jats:sec>

The posterior condylar vein is an emissary vein that connects the extracranial and intracranial venous systems through the posterior condylar canal (PCC). Dural arteriovenous fistulas (DAVF) of the PCC are rare, and only seven cases have been reported. Transvenous embolization (TVE) is the first-line treatment for PCC DAVF and is predominantly performed through the internal jugular vein. Herein, we report a case of PCC DAVF treated with TVE through the deep cervical vein. This is the first case report of a PCC DAVF treated with TVE through the deep cervical vein.

OBJECTIVES: This study aimed to determine the impact of the approval of prothrombin complex concentrates on the treatment of vitamin K antagonist-related intracerebral hemorrhage. MATERIALS AND METHODS: We retrospectively studied all patients with vitamin K antagonist-related intracerebral hemorrhage treated with prothrombin complex concentrate at our institutes between January 2010 and June 2021. Before approval, prothrombin complex concentrate was administered as either 500 or 1000 IU at the physician's discretion (previous dose group). After approval, we adopted the manufacturer's recommended regimen (recommended dose group). The primary outcome was post-administration international normalized ratio. Secondary outcomes were the amount of prothrombin complex concentrate administered and proportion of post-administration international normalized ratio <1.5, hematoma expansion, thrombotic events within 30 days, modified Rankin scale 0-3 at discharge, and in-hospital mortality. RESULTS: Thirty-two and 19 patients in the previous and recommended dose groups, respectively, were included. The post-administration international normalized ratio significantly differed between groups. The prothrombin complex concentrate dose and proportion of patients achieving post-administration international normalized ratio <1.5 were significantly higher in the recommended dose group than in the previous dose group (1500 IU vs. 500 IU, p<0.001 and 100% vs. 68%, p = 0.008). The proportions of hematoma expansion, thromboembolic events, modified Rankin scale 0-3, and mortality did not differ between groups. CONCLUSION: After prothrombin complex concentrate approval, prothrombin time-international normalized ratio correction was more effective with a significant increase in the prothrombin complex concentrates dose for vitamin K antagonist-associated intracerebral hemorrhage; however, there was no apparent difference in clinical outcomes.

OBJECTIVES: The benefit of mechanical thrombectomy for acute ischemic stroke is highly time dependent. However, time to treatment is longer for in-hospital stroke patients than community-onset stroke patients. This study aimed to clarify the cause of this difference. METHODS: A retrospective single-center study was performed to analyze patients with large vessel occlusion who underwent mechanical thrombectomy between January 2017 and December 2019. Patients were divided into in-hospital stroke and community-onset stroke groups. Clinical characteristics and treatment time intervals were compared between groups. RESULTS: One hundred four patients were analyzed: 17 with in-hospital stroke and 87 with community-onset stroke. Patient characteristics did not significantly differ between groups. Median door (stroke recognition)-to-computed tomography time (36 min vs. 14 min, P<0.01) and door-to-puncture time (135 min vs. 117 min, P=0.02) were significantly longer in the in-hospital stroke group than the community-onset stroke group. However, median computed tomography-to-puncture time (104 min vs. 104 min, P=0.47) and puncture-to-reperfusion time (53 min vs. 38 min, P=0.17) did not significantly differ. CONCLUSIONS: Longer door-to-puncture time in in-hospital stroke patients was mostly caused by longer door-to-computed tomography time, which is the initial part of the workflow. An in-hospital stroke protocol that places importance on early stroke specialist consultation and prompt transportation to the computed tomography scanner might hasten treatment and improve outcomes in patients with in-hospital stroke.

We report a case of vertebral artery dissecting aneurysm (VADA) that developed with subarachnoid hemorrhage and was found to be occluded based on subsequent digital subtraction angiography. Few reports have been published on ruptured VADA in which ipsilateral vertebral arteries are occluded. The proper management of this type of aneurysm is controversial. A 44-year-old woman developed a sudden onset headache. Computed tomography and three-dimensional computed tomography were immediately performed and showed subarachnoid hemorrhage and VADA distal to the right posterior inferior cerebellar artery bifurcation. We decided to treat the VADA immediately and performed digital subtraction angiography but found the VADA had spontaneously occluded. We performed coil embolization, including the aneurysm and the parent artery, with reference to the findings of three-dimensional computed tomography. On Day 16, recurrence was considered due to the finding of dilation of the distal end where the coil was embolized. An additional embolization was performed via the posterior communicating artery. No cases of endovascular treatment have been reported in VADA cases in which the rupture site is spontaneously occluded. In such cases, the treatment may be incomplete, so strict follow-up is required.

The PulseRider (Cerenovus, Johnson & Johnson Medical Devices, New Brunswick, NJ, USA) is a neck reconstruction device that is used for the treatment of unruptured wide-necked bifurcation aneurysms. Herein, we describe the case of a 51-year-old male patient with a basilar apex aneurysm who was treated with PulseRider but had post-procedural brainstem infarctions caused by one of the proximal markers covering the origin of a perforator. In such cases, repositioning of the PulseRider should be performed to avoid infarctions.

<jats:sec><jats:title>Background</jats:title><jats:p>Recurrent complex middle cerebral artery (MCA) aneurysms after combined clipping and endovascular surgery are challenging, and if conventional techniques are adapted, advanced surgical, endovascular, and a combination of both techniques are often required. For such complex aneurysms, safe and effective straightforward techniques for all neurovascular surgeons are warranted. We describe the details of staged hybrid techniques with straightforward bypass surgery followed by flow diverter deployment in a patient with complex MCA aneurysm.</jats:p></jats:sec><jats:sec><jats:title>Illustrative Case</jats:title><jats:p>A 69-year-old woman presented with left recurrent large MCA aneurysm enlargement 25 years after direct surgery and coil embolization for ruptured aneurysm. The recurrent MCA aneurysm had large and complex morphology and was adhering to the brain tissues. Therefore, it was unsuitable to treat such aneurysm with conventional surgical and endovascular techniques with a high risk of morbidity. We performed (1) M2 ligation following superficial temporal artery-M2 bypass and (2) flow diverter deployment assisted with coil packing in two sessions. Three months after the second session, the aneurysm was completely occluded with endothelialization of the neck. Angiographic findings revealed no recurrence 12 months after the treatment.</jats:p></jats:sec><jats:sec><jats:title>Conclusions</jats:title><jats:p>Staged hybrid techniques with straightforward bypass surgery followed by flow diverter deployment may be a safe and effective treatment for complex recurrent MCA aneurysms.</jats:p></jats:sec>

PURPOSE: The Flow Re-direction Endoluminal Device (FRED) has recently become available for flow diversion in Japan. We have encountered cases that failed to deploy the FRED. In this study, we report our initial experience with the FRED for cerebral aneurysms and clarify the causes of failed FRED deployment. METHODS: A retrospective data analysis was performed to identify patients treated with the FRED between June 2020 and March 2021. Follow-up digital subtraction angiography was performed at 3 and 6 months and assessed using the O'Kelly-Marotta (OKM) grading scale. RESULTS: Thirty-nine aneurysms in 36 patients (average age: 54.4 years) were treated with the FRED. The average sizes of the dome and neck were 9.9 mm and 5.2 mm, respectively. In nine patients, additional coiling was performed. In one patient (2.6%), proximal vessel injury caused direct carotid-cavernous fistula during deployment. Ischaemic complications were encountered in one patient (2.6%) with transient symptoms. Angiographic follow-up at 6 months revealed OKM grade C or D in 86.6% of patients. FRED deployment was successful in 35 (92.1%) procedures. In the failure group, the differences between the FRED and the minimum vessel diameter (P = 0.04) and the rate of the parent vessel having an S-shaped curve (P = 0.04) were greater than those in the success group. CONCLUSIONS: Flow diversion using the FRED is effective and safe for treating cerebral aneurysms. The use of the FRED for patients with an S-shaped curve in the parent vessel and oversizing of more than 2 mm should be considered carefully.

PURPOSE: Endovascular treatment of posterior communicating artery aneurysms with fetal-type posterior communicating artery originating from the aneurysm dome is often challenging because, with conventional techniques, dense packing of aneurysms for posterior communicating artery preservation is difficult; moreover, flow-diversion devices are reportedly less effective. Herein, we describe a novel method called the λ stenting technique that involves deploying stents into the internal carotid artery and posterior communicating artery. METHODS: Between January 2018 and September 2020, the λ stenting technique was performed to treat eight consecutive cases of aneurysms. All target aneurysms had a wide neck (dome/neck ratio < 2), a fetal-type posterior communicating artery with hypoplastic P1, and a posterior communicating artery originating from the aneurysm dome. The origin of the posterior communicating artery from the aneurysm, relative to the internal carotid artery, was steep (< 90°: V shape). RESULTS: The maximum aneurysm size was 8.0 ± 1.9 mm (6-12 mm). The average packing density (excluding one regrowth case) was 32.7 ± 4.2% (26.8-39.1%). Initial occlusion was complete occlusion in 6 (75.0%) patients and neck remnants in 2 (25.0%) patients. Follow-up angiography was performed at 18.4 ± 11.6 months (3-38 months). There were no perioperative complications or reinterventions required during the study period. CONCLUSION: The λ stenting technique enabled dense coil packing and preservation of the posterior communicating artery. This technique enabled safe and stable coil embolization. Thus, it could become an alternative treatment option for this sub-type of intracranial aneurysms.

BACKGROUND: Thromboembolic complications (TECs) are frequent during the endovascular treatment of unruptured aneurysms. To prevent TECs, dual antiplatelet therapy using aspirin and clopidogrel is recommended for the perioperative period. In patients with a poor response, clopidogrel is a risk factor for TECs. To prevent TECs, our study assessed the stratified use of prasugrel. METHODS: Patients who underwent endovascular therapy for unruptured cerebral aneurysms from April 2017 to August 2019 were enrolled in this clinical study and given premedication with aspirin and clopidogrel for 2 weeks prior to the procedure. P2Y12 reaction units (PRU) were measured using the VerifyNow assay on the day before the procedure (tailored group). In subgroups with PRU <240, the clopidogrel dose was maintained (CPG subgroup). In subgroups with PRU ≥240, clopidogrel was changed to prasugrel (PSG subgroup). We compared the occurrence of TECs with retrospective consecutive cases from January 2015 to March 2017 without PRU assessments (non-tailored group). The frequency of TECs within 30 days was assessed as the primary endpoint. RESULTS: The tailored and non-tailored groups comprised 167 and 50 patients, respectively. TECs occurred in 11 (6.6%) and 8 (16%) patients in the tailored and non-tailored groups (P=0.048), respectively. The HR for TECs was significantly reduced in the tailored group (HR 0.3, 95% CI 0.11 to 0.81); P=0.017) compared with the non-tailored group. CONCLUSION: The results suggest that tailored dual antiplatelet therapy medication with PRU significantly reduces the frequency of TECs without increasing hemorrhagic complications.

BACKGROUND: The World Federation of Neurosurgical Societies (WFNS) scale is widely accepted for predicting outcomes for subarachnoid hemorrhage (SAH) patients. However, it is difficult to definitely predict outcomes for the most poor grade, WFNS grade 5. The present study aimed to investigate the prognostic ability of a novel classification using computed tomography perfusion (CTP) findings, called the cortical blood flow insufficiency (CBFI) scores. METHODS: CTP was performed on admission for aneurysmal SAH followed by radical treatments within 72 hours of onset. Twenty-four cerebral cortex regions of interest (ROIs) were defined. CBFI was defined as Tmax > 4 s in each ROI, and CBFI scores were calculated based on the total number of ROIs with CBFI. Using the optimal cutoff value based on receiver operating characteristics (ROC) analysis to predict patient functional outcomes, CBFI scores were divided into "high" or "low" CBFI scores. Patient functional outcomes at 90 days were categorized based on modified Rankin Scale scores (0-3, favorable group; 4-6 unfavorable group) (0-4, non-catastrophic group; 5-6, catastrophic group). RESULTS: Fifty-seven patients were included in this study, of whom 21 (36.8%) and 13 (22.8%) were in the unfavorable and the catastrophic groups, respectively. A factor predicting unfavorable and catastrophic outcomes was CBFI score cutoff value of 7 points (area under the curve, 0.73 and 0.81, respectively). In multivariable logistic regression analysis for unfavorable outcome, high CBFI scores (odds ratio (OR), 8.6; 95% confidence interval (CI), 1.1-65.4; P = 0.04) and WFNS grade 5 (OR, 30.0; 95% CI, 4.5-201.0; P < 0.001) remained as independent predictors, while for catastrophic outcome, high CBFI scores (OR, 25.3; 95% CI, 3.3-194.0; P = 0.002) and age (OR, 1.1; 95% CI, 1.0-1.2; P = 0.02) remained as independent predictors. Conversely, WFNS grade 5 was not an independent predictor of catastrophic outcomes (OR, 3.8; 95% CI, 0.6-24.0; P = 0.15). In high CBFI scores, the OR of the delayed cerebral ischemia (DCI) occurrence was 9.6 (95% CI, 1.5-61.4; P = 0.02) after adjusting for age. CONCLUSION: High CBFI scores could predict unfavorable and catastrophic outcomes for aneurysmal SAH patients and DCI occurrence.

Mechanical thrombectomy using a retrograde approach is performed for tandem occlusion of the internal carotid artery (ICA). In our patient, a guiding catheter was easily passed by the stenosed lesion despite severe stenosis at the ICA origin. Therefore, we aimed to recanalize the occlusion of the terminal ICA without angioplasty for the stenosed lesion. When contrast was injected, a massive extravasation of contrast from the C2 portion of the ICA was observed. It was speculated that the bleeding was caused by rupture of an aneurysm at that site due to increased intra-arterial pressure caused by the contrast injection to a blind alley, which was created by a wedged guiding catheter at severe stenosis at the ICA origin and the occlusion of the terminal ICA. Our simulation experiment using a silicon vascular model in this situation demonstrated that the elevation of intra-arterial pressure in such blind alley reached over 50, 100, and 200 mmHg by injection of contrast from a microcatheter, a 4-Fr inner catheter, and a 9-Fr balloon-guiding catheter, respectively. When a retrograde approach is planned for tandem occlusion of the ICA, even when the proximal lesion is easily passed, prior angioplasty for the proximal lesion should be considered to avoid wedging by catheter.

This pilot study aimed to investigate the utility of near-infrared spectroscopy/indocyanine green (NIRS/ICG) for examining patients with occlusive cerebrovascular disease. Twenty-nine patients with chronic-stage atherosclerotic occlusive cerebrovascular disease were included. The patients were monitored using NIRS at the bedside. Using ICG time-intensity curves, the affected-to-unaffected side ratios were calculated for several parameters, including the maximum ICG concentration (ΔICGmax), time to peak (TTP), rise time (RT), and blood flow index (BFI = ΔICGmax/RT), and were compared to the affected-to-unaffected side ratios of the regional cerebral blood flow (rCBF) and regional oxygen extraction fraction (rOEF) obtained using positron emission tomography with 15 O-labeled gas. The BFI ratio showed the best correlation with the rCBF ratio among these parameters (r = 0.618 P = 0.0004), and the RT ratio showed the best correlation with the rOEF ratio (r = 0.593 P = 0.0007). The patients were further divided into reduced rCBF or elevated rOEF groups, and the analysis revealed significant related differences. The present results advance the measurement of ICG kinetics using NIRS as a useful tool for the detection of severely impaired perfusion with reduced rCBF or elevated rOEF. This method may be applicable as a monitoring tool for patients with acute ischemic stroke.

Background: Posterior communicating artery (PCoA) aneurysms are among the most common aneurysms. Because blockage of the PCoA and perforators can cause adverse outcomes, occlusion of these arteries by surgical clipping should be avoided. The impact of factors on PCoA perforator infarction when using a distal transsylvian approach for PCoA aneurysms was examined. Methods: A total of 183 patients underwent PCoA aneurysm clipping, excluding application of fenestrated clips. Patients were divided into 2 groups: patients with PCoA perforator infarction (infarction group) and patients without infarction (noninfarction group). Multiple factors were analyzed in the 2 groups. Results: Twenty-two of the 183 patients (12.0%) showed perforator infarction, mainly on magnetic resonance imaging evaluation, resulting in permanent deficits in 2 patients (1.1%). The proportion of right-sided operations (86.4% vs. 53.4% P = 0.005) and surgery for rupture (90.9% vs. 55.9% P = 0.002) were significantly higher in the infarction group than in the noninfarction group. Aneurysms were significantly larger in the infarction group (8.4 ± 3.8 mm) than in the noninfarction group (6.3 ± 3.0 mm P = 0.02). Ruptured status (odds ratio [OR], 7.35 P = 0.01), right side (OR, 5.19 P = 0.01), and aneurysm size (OR, 1.18 P = 0.02) remained independent predictors of perforator infarction on multivariate logistic regression analysis. Conclusions: Ruptured status, right side, and large PCoA aneurysm were independent predictors of PCoA perforator infarction. Symptoms due to PCoA perforating infarction were mostly transient and rarely affected outcomes.

BACKGROUND: Recurrent aneurysms after initial clipping have been discussed as an important issue in the surgical management of aneurysm. OBJECTIVE: To report our experience with recurrent cerebral aneurysms after neck clipping and to discuss classification and recommended management. METHODS: Aneurysm treatments from a single institution over a 20-year period were retrospectively reviewed. Twenty-three recurrent aneurysms in 23 patients weremanaged during the study period. Recurrent aneurysmswere classified using the concepts of closure line and closure plane, as follows. Type 1: neck situated in an almost different site from the previous clip. Type 2: existing closure plane and reconstructive closure plane are almost the same. Type 3: existing closure plane and reconstructive closure plane cross (type 3a) in rare cases, the existing closure line is sufficiently distant fromthe neck (type 3b). Type 4: no reconstructive closure line is identifiable. RESULTS: Nine patients presented with subarachnoid hemorrhage at recurrence. The mean interval to recurrence was 15.0 years.Management comprised clipping with elective subsequent old-clip removal (n = 7), clipping with preceding old-clip removal (n = 2), bypass occlusion (n = 1), coating (n = 1), combined surgery (n = 1), endovascular surgery (n = 4), and observation (n = 3). Therapeutic intervention was not indicated in 4 patients. Types 3a and 4 requiredmore complex surgical procedures or coil embolization. Procedural complications were observed in 2 patients. CONCLUSION:Asmall but definite propensity toward recurrence after neck clipping exists, and most recurrent aneurysms require some form of retreatment. The novel classification scheme may provide conceptual clarity and therapeutic guidance for decision making.

Introduction A major disadvantage of carotid artery stenting (CAS) is the high incidence of perioperative cerebral embolism. Cerebral embolism after CAS is associated with soft plaque. Currently, higher spatial resolution imaging can be obtained with cone-beam CT (CB-CT). The correlation between the degree of contrast enhancement of the vasa vasorum (VV) on CB-CT and the vulnerability of plaque in terms of risk factors for CAS was evaluated. Methods 18 patients who underwent CAS had high-resolution CB-CT to evaluate enhancement of the VV covering carotid plaque performed intraoperatively. The appearance of the surface of the carotid plaque was classified as either enhancing (VV-positive) or non-enhancing (VV-negative). Carotid plaque vulnerability on black-blood MRI (BB-MRI) and postoperative ipsilateral ischemic lesions on diffusion-weighted imaging (DWI) were analyzed in the two groups. Results Of the 18 patients, 9 were VV-positive and 9 were VV-negative. The proportion of ipsilateral new ischemic lesions on DWI was significantly higher in the VV-positive group than in the VV-negative group (8/9 patients (88.9%) vs 3/9 patients (33.3%), p=0.026). BB-MRI was performed preoperatively in 15 of 18 patients. The proportion of unstable plaque on BB-MRI was significantly higher in the VV-positive group than in the VV-negative group (9/9 patients (100%) vs 1/6 patients (16.7%), p=0.002). Conclusions Enhancement of the VV covering carotid plaque on high-resolution CB-CT was significantly associated with unstable plaque on BB-MRI and postoperative ipsilateral new ischemic lesions.

症例1は55歳女性で、頭痛精査で10mm大の右M1-M2動脈瘤を認め、経過観察中に動脈瘤は14mmと増大し、右M1に紡錘状動脈瘤の新生を認めて手術を行った。M1-M2動脈瘤にはwrappingを行い、M1動脈瘤にclippingを行った後に、M1-M2動脈瘤にwrap and clipを行い、Gore-TexをWeck clipで密に被覆した。術後経過は良好で、術後61ヵ月経過で増大や破裂は認めていない。症例2は39歳男性で、左上肢の脱力で発見された未破裂前交通動脈瘤に対しinterhemispheric approachにてneck clippingを行ったが、左A2を動脈瘤から剥離する際に損傷をきたし、圧迫止血後にゼラチンスポンジとfibrin glueで補強したが、術後6日目の血管撮影で左A2にpseudoaneurysmを認め、再手術で左A2とpseudoaneurysmを周囲組織から完全に剥離してGore-Texで被覆し、wrap and clipとした。術後経過は良好で、術後2ヵ月目の脳血管撮影でpseudoaneurysmの消失を確認した。

Objective: Aging is considered to cause atherosclerotic changes in the carotid artery, but few studies have evaluated this relationship. In this study, we used carotid plaques removed from patients with carotid artery stenosis and investigated how aging contributes to carotid plaque morphology and symptoms. Materials and Methods: A total of 60 patients (55 men, 5 women mean age, 70.5 years range, 53-85 years) treated at our hospital between January 2009 and April 2012 were enrolled in this study. All patients underwent carotid endarterectomy their carotid plaques were stained with hematoxylin-eosin and/or Elastica-Masson stain and examined by a pathologist. Using these data, the carotid systolic velocity and plaque morphology were analyzed considering the age by decade as well as the symptomatology. Results: Of the 60 patients, 29 were symptomatic (transient ischemic attack (TIA) in 8 patients infarction in 20 and amaurosis in 1). Symptoms were less common as patient age increased. The incidence of TIA also tended to decrease with an increase in age, although the opposite trend was seen with infarction. In plaque morphology, the presence of active plaque, macrophage, inflammatory infiltration, and capillary angiogenesis decreased as age increased, while the presence of degenerative plaques, decrease in smooth muscle cell number, and calcification inversely increased. Active, degenerative, and combined (active/degenerative) lesions are statistically unrelated to symptoms as well as systolic velocity (cm/sec) at the carotid stenosis. The rates of hemorrhagic lesions were similar among decades, but the lesion statistically contributed to increasing symptoms (p=0.0045) and increasing systolic velocity (p=0.03l). Conclusion: Increasing age contributes to morphological changes in carotid plaques and symptoms. When hemorrhagic lesions are suspected in carotid plaques, patients will be symptomatic and may require surgery.

Carotid plaque constituents such as hemorrhage, lipid core, fibrosis, and calcification are important factors in predicting the clinical outcome of carotid artery stenting (CAS). Magnetic resonance imaging (MRI) can noninvasively assess changes in carotid plaque composition by evaluating the Sp/Sm ratio calculated with the signal intensity of carotid plaque (Sp) compared to that of sternocleidomastoid muscle (Sm) using the black-blood technique. <br> In the current study, we assessed the effects of 5 mg rosuvastatin and 1,800 mg eicosapentaenoic acid (EPA) on carotid plaque composition and volume using MRI and intravascular ultrasound prior to CAS. Thirty consecutive patients with atherosclerotic carotid stenosis were randomly divided into two groups—an EPA/rosuvastatin group (n=15) and a control group (n=15)—and then were treated with CAS. Perioperative complications and postoperative high spotty lesions on diffusion weighted image (DWI) were compared between the two groups. As a result, EPA and rosuvastatin significantly reduced the Sp/Sm ratio in both T1- and T2-weighted images in patients with unstable plaques (T1; p=0.021, T2; p=0.014). Plaque volume was also reduced between baseline and follow-up in 4 of 15 cases treated with EPA/rosuvastatin. The number of postoperative high spotty lesions on DWI significantly decreased in the EPA/rosuvastatin group (13%; 2/15) compared with the control group (40%; 6/15, p<0.05), whereas no significant difference was observed in perioperative complication rate. <br> The combined therapy of EPA and rosuvastatin leads to a benefical effect on plaque composition and volume, which may contribute to reducing the ischemic complications with CAS, particular in patients with vulnerable plaque.<br>