早川 基治

BACKGROUND AND PURPOSE: Tumor embolization through the meningohypophyseal trunk and inferolateral trunk is known to be effective in skull-based tumors; however, microcatheter cannulation into these arteries is difficult, and the number of cases that can be safely embolized is limited. In this study, we present a novel embolization procedure for meningohypophyseal trunk and inferolateral trunk using the distal balloon protection technique and detail its clinical efficacy and complication risks. We developed this procedure to allow safe embolization in patients who cannot be adequately cannulated with microcatheters into these arteries. MATERIALS AND METHODS: Patients who underwent meningohypophyseal trunk or inferolateral trunk embolization using the distal balloon protection technique for skull-based tumors at our institution between 2010 and 2023 were included. In this procedure, the ICA was temporarily occluded with a balloon at the ophthalmic artery bifurcation, the microcatheter was guided to the meningohypophyseal trunk or inferolateral trunk vicinity, and embolic particles were injected into the arteries. The balloon was deflated after the embolic particles, that had refluxed into the ICA, were aspirated. RESULTS: A total of 25 meningohypophyseal trunks and inferolateral trunks were embolized during 21 surgeries. Of these 25 arteries, only nine (36.0%) were successfully cannulated with microcatheters. Nevertheless, effective embolization was achieved in all cases. Permanent complications occurred in only one case (4.8%), in which the central retinal artery was occluded during inferolateral trunk embolization, resulting in a visual field defect. No permanent complications resulting from the embolic cerebral infarction were observed. Of 16 cases that underwent MRI within a week after embolization, however, 11 (68.8%) demonstrated embolic cerebral infarctions. CONCLUSIONS: In patients with skull-based tumors with meningohypophyseal trunk or inferolateal trunk feeders that cannot be catheterized directly, embolization using the distal balloon protection technique for tumor supply can be considered as a salvage technique. ABBREVIATIONS: MHT = meningohypophyseal trunk; ILT = inferolateral trunk; GC = guide catheter; AC = aspiration catheter; FR = flow reverse.

BACKGROUND: In intraventricular surgery using a flexible endoscope, the lesion is usually aspirated via the working channel. However, the surgical view during aspiration is extremely poor because the objective lens is located adjacent to the working channel. METHOD: To address this issue, we developed a novel surgical procedure using an angiographic catheter. In this procedure, the catheter is inserted into the working channel, and the lesion is aspirated through the catheter. Besides, continuous intraventricular irrigation is performed via the gap between the catheter and the working channel. CONCLUSION: This procedure maintains a clear view during surgery and reduces complications.

Ischemia-induced postoperative scalp necrosis in the superficial temporal artery (STA) region is known to occur after STA-middle cerebral artery anastomoses. However, no reports have evaluated the risk of postoperative scalp necrosis in the occipital artery (OA) region. This study examined the surgical procedures that pose a risk for postoperative scalp necrosis in the OA region following posterior cranial fossa surgery. Patients who underwent initial posterior fossa craniotomy at our institution from 2015 to 2022 were included. Clinical information was collected using medical records. Regarding surgical procedures, we evaluated the incision design and whether a supramuscular scalp flap was prepared. The supramuscular scalp flap was defined as a scalp flap dissected from the sternocleidomastoid and/or splenius capitis muscles. A total of 392 patients were included. Postoperative scalp necrosis occurred in 19 patients (4.8%). There were 296 patients with supramuscular scalp flaps, and supramuscular scalp flaps prepared in all 19 patients with postoperative necrosis. Comparing incision designs among patients with supramuscular scalp flap, a hockey stick-shaped scalp incision caused postoperative necrosis in 14 of 73 patients (19.1%), and the odds of postoperative scalp necrosis were higher with the hockey stick shape than with the retro-auricular C shape (adjusted odds ratio: 12.2, 95% confidence interval: 3.86-38.3, p = 0.00002). In all the cases, ischemia was considered to be the cause of postoperative necrosis. The incidence of postoperative necrosis is particularly high when a hockey stick-shaped scalp incision is combined with a supramuscular scalp flap.

Objective  Plaque induction through intimal injury using a balloon catheter in small animals and by artificial ligation of the carotid artery in large animals have been reported. However, these reports have not yet succeeded in inducing stable plaques nor creating a high degree of intimal thickening to be used as animal models. We have previously developed a plaque induction model in rats but have failed to obtain a plaque incidence frequency that can be used as a model. Thus, in the current study, we aimed to create a versatile disease model to examine the pharmacokinetics of drug administration, determine the efficacy of treatment, and examine the process of intimal thickening. We also attempted to create an improved model with shorter, more frequent, and more severe intimal thickening. Materials and Methods  The common carotid artery of male Wistar rats was surgically exposed and completely ligated with a wire and 6-0 nylon thread. Then, the wire was removed to create a partial ligation. To create a high frequency and high degree of intimal thickening, 72 rats were divided into two groups: a single lesion group with a 0.25-mm wire and a single ligature point, and a tandem lesion group with a 0.3-mm wire and two ligature points. Each group was further divided into normal diet and high cholesterol diet groups. The presence and frequency of intimal thickening were examined for each group after 4, 8, and 16 weeks of growth. Results  In the single lesion group, intimal thickening was observed in 42% of the 4-week group and 75% of the 8-week group. In the tandem lesion group, intimal thickening was observed in 75% of the 4-week group and 50% of the 8-week group. In addition, 50% of the individuals reared for 16 weeks developed intimal thickening. Conclusion  We successfully induced intimal thickening in the carotid arteries of rats with high frequency in the single lesion and tandem lesion groups. The results also showed that the tandem lesion group tended to induce intimal thickening earlier than the single lesion group.

BACKGROUND: The Uncal vein (UV), downstream of the deep middle cerebral vein (DMCV), has a similar drainage pattern to the superficial middle cerebral vein (SMCV) and may be involved in venous complications during the anterior transpetrosal approach (ATPA). However, in petroclival meningioma (PCM), where the ATPA is frequently used, there are no reports evaluating drainage patterns of the UV and the risk of venous complications associated with the UV during the ATPA. METHODS: Forty-three patients with petroclival meningioma (PCM) and 20 with unruptured intracranial aneurysm (control group) were included. Preoperative digital subtraction angiography was used to evaluate UV and DMCV drainage patterns on the side of the tumor and bilaterally in patients with PCM and the control group, respectively. RESULTS: In the control group, the DMCV drained to the UV, UV and BVR, and BVR in 24 (60.0%), eight (20.0%), and eight (20.0%) hemispheres, respectively. Conversely, the DMCV in the patients with PCM drained to the UV, UV and BVR, and BVR in 12 (27.9%), 19 (44.2%), and 12 (27.9%) patients, respectively. The DMCV was more likely to be drained to the BVR in the PCM group (p < 0.01). In three patients with PCM (7.0%), the DMCV drained only to the UV, and furthermore, the UV drained to the pterygoid plexus via the foramen ovale, posing a risk for venous complications during the ATPA. CONCLUSIONS: In the patients with PCM, the BVR functioned as a collateral venous pathway of the UV. Preoperative evaluation of the UV drainage patterns is recommended to reduce venous complications during the ATPA.

OBJECTIVE: Although a qualitative diagnosis of plaque causing carotid stenosis has been attempted with carotid computed tomography angiography (CaCTA), no clear findings have been reported. We examined the correlation between the plaque CT values and plaque images obtained by magnetic resonance imaging to derive a qualitative diagnosis of the plaque using CaCTA. METHODS: Preoperative CaCTA images acquired from patients stented for carotid stenosis were retrospectively analyzed with respect to magnetization-prepared rapid acquisition with gradient echo and time-of-flight magnetic resonance angiography data. Carotid plaques in the stenosed region were quantified in terms of CT density and the plaque/muscle ratio (magnetization-prepared rapid acquisition with gradient echo), and correlations between these 2 features were determined. Plaques were classified as stable or unstable based on the plaque/muscle ratio, with the smallest plaque/muscle ratio observed among plaques positive for intraplaque hemorrhage set as the cutoff value (1.76). RESULTS: A total of 165 patients (179 plaques) were included. Perioperative complications included minor stroke (n = 3), major stroke (n = 1, fatal), and hyperperfusion (n = 2). The correlation between CT density and the plaque/muscle ratio was nonlinear (P = 0.0139) and negative (P < 0.0001). The cutoff point (1.76) corresponded to a CT density of 83 HU, supporting this value as a standard reference for plaque stability. CONCLUSIONS: Computed tomography density exhibits a nonlinear (P = 0.0139) and highly negative correlation (P < 0.0001) with the plaque/muscle ratio. Our results demonstrate that plaque characteristics can be meaningfully diagnosed based on CaCTA image data.

Collateral circulation in the circle of Willis (CoW), closely associated with disease mechanisms and treatment outcomes, can be effectively investigated using one-dimensional-zero-dimensional hemodynamic simulations. As the entire cardiovascular system is considered in the simulation, it captures the systemic effects of local arterial changes, thus reproducing collateral circulation that reflects biological phenomena. The simulation facilitates rapid assessment of clinically relevant hemodynamic quantities under patient-specific conditions by incorporating clinical data. During patient-specific simulations, the impact of clinical data uncertainty on the simulated quantities should be quantified to obtain reliable results. However, as uncertainty quantification (UQ) is time-consuming and computationally expensive, its implementation in time-sensitive clinical applications is considered impractical. Therefore, we constructed a surrogate model based on machine learning using simulation data. The model accurately predicts the flow rate and pressure in the CoW in a few milliseconds. This reduced computation time enables the UQ execution with 100 000 predictions in a few minutes on a single CPU core and in less than a minute on a GPU. We performed UQ to predict the risk of cerebral hyperperfusion (CH), a life-threatening condition that can occur after carotid artery stenosis surgery if collateral circulation fails to function appropriately. We predicted the statistics of the postoperative flow rate increase in the CoW, which is a measure of CH, considering the uncertainties of arterial diameters, stenosis parameters, and flow rates measured using the patients' clinical data. A sensitivity analysis was performed to clarify the impact of each uncertain parameter on the flow rate increase. Results indicated that CH occurred when two conditions were satisfied simultaneously: severe stenosis and when arteries of small diameter serve as the collateral pathway to the cerebral artery on the stenosis side. These findings elucidate the biological aspects of cerebral circulation in terms of the relationship between collateral flow and CH.

Meningiomas are a common pathology in the central nervous system requiring complete surgical resection. However, in cases of recurrence and post-irradiation, accurate identification of tumor remnants and a dural tail under bright light remains challenging. We aimed to perform real-time intraoperative visualization of the meningioma and dural tail using a delayed-window indocyanine green (ICG) technique with microscopy. Fifteen patients with intracranial meningioma received 0.5 mg/kg ICG a few hours before observation during the surgery. We used near-infrared (NIR) fluorescence to identify the tumor location. NIR fluorescence could visualize meningiomas in 12 out of 15 cases. Near-infrared visualization during the surgery ranged from 1 to 4 h after the administration of ICG. The mean signal-to-background ratio (SBR) of the intracranial meningioma in delayed-window ICG (DWIG) was 3.3 ± 2.6. The ratio of gadolinium-enhanced T1 tumor signal to the brain (T1BR) (2.5 ± 0.9) was significantly correlated with the tumor SBR (p = 0.016). K^trans, indicating blood–brain barrier permeability, was significantly correlated with tumor SBR (p &amp;lt; 0.0001) and T1BR (p = 0.013) on dynamic contrast-enhanced magnetic resonance imaging (MRI). DWIG demonstrated a sensitivity of 94%, specificity of 38%, positive predictive value (PPV) of 76%, and negative predictive value (NPV) of 75% for meningiomas. This is the first pilot study in which DWIG fluorescence-guided surgery was used to visualize meningioma and dural tail intraoperatively with microscopy. DWIG is comparable with second-window ICG in terms of mean SBR. Gadolinium-enhanced T1 tumor signal may predict NIR fluorescence of the intracranial meningioma. Blood–brain barrier permeability as shown by K^trans on dynamic contrast-enhanced MRI can contribute to gadolinium enhancement on MRI and to ICG retention and tumor fluorescence by NIR.

Background: We aimed to clarify the relationship between epicardial adipose tissue (EAT) volume and the presence of severe stenoses (SS) on coronary computed tomography angiography (CTA) for risk stratification of the patients with carotid artery stenoses. Methods: We prospectively performed CTA for 125 consecutive patients (72.4 ± 8.1 years, 85% men) without a history of coronary artery disease (CAD), who were scheduled for carotid artery revascularization from 2014 to 2020. SS was defined as ≥70% luminal stenosis on CTA. EAT was quantified automatically as the total volume of tissue with -190 to -30 HU. Results: Of 125 patients, 76 had SS. Between the patients with and without SS, there were significant differences in coronary artery calcium score (CACS), left ventricular ejection fraction (LVEF), dyslipidemia, and EAT, despite no differences in carotid echocardiography findings. After adjustment for age, gender, and dyslipidemia, EAT was an independent factor associated with SS (p=0.011), as well as CACS and LVEF. The addition of EAT to a baseline model including age, gender, dyslipidemia, LVEF, and CACS achieved both net reclassification improvement (0.505, p=0.003) and integrated discrimination improvement (0.059, p=0.003). Conclusions: In patients with carotid stenoses, EAT is associated with CAD and is useful for additional risk stratification. Epicardial fat may have a specific role in the development of CAD in patients with suspected systemic atherosclerosis.

OBJECTIVE: Relationships between aneurysm initiation and hemodynamic factors remain unclear since de novo aneurysms are rarely observed. Most previous computational fluid dynamics (CFD) studies have used artificially reproduced vessel geometries before aneurysm initiation for analysis. In this study, the authors investigated the hemodynamic factors related to aneurysm initiation by using angiographic images in patients with cerebral aneurysms taken before and after an aneurysm formation. METHODS: The authors identified 10 cases of de novo aneurysms in patients who underwent follow-up examinations for existing cerebral aneurysms located at a different vessel. The authors then reconstructed the vessel geometry from the images that were taken before aneurysm initiation. In addition, 34 arterial locations without aneurysms were selected as control cases. Hemodynamic parameters acting on the arterial walls were calculated by CFD analysis. RESULTS: In all de novo cases, the aneurysmal initiation area corresponded to the highest wall shear stress divergence (WSSD point), which indicated that there was a strong tensile force on the arterial wall at the initiation area. The other previously reported parameters did not show such correlations. Additionally, the pressure loss coefficient (PLc) was statistically significantly higher in the de novo cases (p < 0.01). The blood flow impact on the bifurcation apex, or the secondary flow accompanied by vortices, resulted in high tensile forces and high total pressure loss acting on the vessel wall. CONCLUSIONS: Aneurysm initiation may be more likely in an area where both tensile forces acting on the vessel wall and total pressure loss are large.

Flow diverters (FDs) are widely employed as endovascular treatment devices for large or wide-neck cerebral aneurysms. Occasionally, overlapped FDs are deployed to enhance the flow diversion effect. In this study, we investigated the hemodynamics of overlapping FDs via computational fluid dynamics (CFD) simulations. We reproduced the arterial geometry of a patient who had experienced the deployment of two overlapping FDs. We utilized two stent patterns, namely the patterns for one FD and two overlapping FDs. We calculated the velocity, mass flow rate, wall shear stress, and pressure loss coefficient as well as their change rates for each pattern relative to the no-FD pattern results. The CFD simulation results indicated that the characteristics of the blood flow inside the aneurysm were minimally affected by the deployment of a single FD; in contrast, the overlapping FD pattern results revealed significant changes in the flow. Further, the velocity at an inspection plane within the aneurysm sac decreased by up to 92.2% and 31.0% in the cases of the overlapping and single FD patterns, respectively, relative to the no-FD pattern. The simulations successfully reproduced the hemodynamics, and the qualitative and quantitative investigations are meaningful with regard to the clinical outcomes of overlapped FD deployment.

Digital subtraction angiography (DSA) assesses the necessity of preoperative embolization in meningioma cases but entails complication risks. Previous studies evaluating meningiomas' angiographic vascularity using perfusion-weighted imaging (PWI) have performed subjective visual assessments, not managing to assess the need for preoperative embolization. We objectively assessed the angiographic stain of meningiomas and examined the usefulness of two parameters of dynamic susceptibility contrast (DSC)-PWI, normalized cerebral blood volume (nCBV) and cerebral blood flow (nCBF), in predicting vascularity and the necessity of preoperative embolization. We retrospectively examined 52 patients who underwent surgery for primary meningioma and preoperative DSA and DSC-PWI. We calculated the normalized luminance (nLum) of the tumor stain in DSA. In 29 meningioma cases with a single feeding artery, we determined the DSC-PWI parameter that correlated with meningioma angiographic vascularity and predicted the necessity of preoperative embolization. We also compared vascularity between meningiomas with single and multiple feeding arteries and between convexity and skull-base meningiomas. nCBF (cut off: 3.66, P = 0.03, area under the curve [AUC] = 0.80) alone could predict the necessity of preoperative embolization and was more significantly correlated with the nLum than nCBV (P = 0.08, AUC = 0.73). Vascularity did not differ between meningiomas with single and multiple feeding arteries; skull-base meningiomas were more vascularized than convexity meningiomas (P = 0.0027). Our objective, quantitative assessments revealed nCBF as the most suitable parameter for evaluating meningioma vascularity. Tumor vascularity assessment using nCBF values and CBF images may aid predicting the necessity of preoperative DSA.

<sec><title>Background</title>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. </sec><sec><title>Methods</title>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 &lt;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. </sec><sec><title>Results</title>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. </sec><sec><title>Conclusion</title>The results suggest that tailored dual antiplatelet therapy medication with PRU significantly reduces the frequency of TECs without increasing hemorrhagic complications. </sec>

Transvenous embolization (TVE) through the superior ophthalmic vein (SOV) is a useful approach for the treatment of cavernous sinus (CS) dural arteriovenous fistulae (DAVFs). This venous route is usually confirmed by angiography. Herein, we present a case of favorable embolization of the CS DAVF through the angiographically occlusive SOV. A 61-year-old man presented with progressive exophthalmos and hypertonia. The patient was diagnosed with a CS DAVF, and TVE was planned. The first approach through the inferior petrosal sinus was infeasible; therefore, we attempted to approach the fistula through the left facial vein. The microcatheter was easily advanced to the shunt point through the angiographically occlusive SOV. We performed coil embolization, and the CS DAVF was completely obstructed.

In order to grasp the spatial and temporal evolution of vascular geometry, three-dimensional (3D) arterial bending structure and geometrical changes of arteries and stent grafts (SG) must be quantified using geometrical parameters such as curvature and torsion along the vasculature centerlines extracted from medical images. Here, we develop a robust method for constructing smooth centerlines based on a spline fitting method (SFM) such that the optimized geometric parameters of curvature and torsion can be obtained independently of digitization noise in the images. Conventional SFM consists of the 3rd degree spline basis function and 2nd derivative penalty term. In contrast, the present SFM uses the 5th degree spline basis function and 3rd and 4th derivative penalty terms, the coefficients of which are derived by the Akaike information criterion. The results show that the developed SFM can reduce the errors of curvature and torsion compared to conventional SFM. We then apply the present SFM to the centerline of the SG in an abdominal aortic aneurysm (AAA), and those of bilateral internal carotid arteries (ICA) in 6 cases: 3 cases with aneurysms and 3 cases without any aneurysm. The SG centerlines were obtained from temporal medical images at three scan times. The strong peak of the curvature could be clearly observed in the distal area of the SG, the inversion of the torsion at 0 months in the middle area of SG disappeared over time, and the torsions around the SG bifurcation at the three time periods were inverted. The curvature-torsion graphs along the ICA centerlines superimposing five aneurysmal positions were useful for investigating the relationship between arterial bending structure and aneurysmal positions. Both ICAs had curvature peak values higher than 0.4 within the ICA syphons. The ICA torsion graphs indicated that left and right ICA tended to be a right- and left-handed helix, respectively. In the left ICA syphon, the biggest aneurysm could be observed downstream of the salient torsion inversion. All aneurysms for 3 cases were positioned at the downstream of the inverted torsion.

Purpose: Diagnostic and neurosurgical procedures require the precise localization of small intracranial arteries, but this may be difficult using conventional computed tomography angiography (CTA). This study was conducted to evaluate the quality of CTA images acquired using a prototype ultra-high-resolution computed tomography (U-HRCT) system compared with those acquired using a conventional computed tomography (C-CT) system. Materials and methods: From July through September 2015, 10 adult patients (6 women and 4 men) previously scanned by C-CT were examined using U-HRCT to locate and assess cerebral aneurysms. The bilateral ophthalmic artery (Opth A), anterior choroidal artery (Acho A), and thalamoperforating arteries (TPAs) were visually evaluated in randomly presented CTA images. Images were graded on a 5-point scale, and differences in scores between U-HRCT and C-CT were evaluated by the Wilcoxon signed-rank test. A p value < 0.05 was considered statistically significant. Results: Visual evaluation scores for images of the Opth A, Acho A, and TPAs were significantly higher for U-HRCT than for C-CT. U-HRCT images achieved good visualization (score > 3) for C-CT images with poor visualization (score < 3) in 66.7–100% of all the small arteries. Conclusion: U-HRCT is superior to C-CT for detecting and evaluating clinically significant small intracranial arteries.

PURPOSE: The use of tablet terminals has been explored in various medical settings; however, caution should be exercised when performing image diagnosis using this technology. The present study examined the characteristics of an iPad Air™ monitor and assessed radiographic image interpretations to verify the reliability of the telediagnosis of acute cerebral infarction based on magnetic resonance imaging (MRI) using a tablet terminal. MATERIALS AND METHODS: The luminance of the iPad Air™ was measured using a UA-10 analyzer, and radiographic image interpretation experiments were performed in 100 patients who underwent MRI within 6 h of symptom onset. Ten physicians viewed the images on the iPad Air™ and a medical monitor, with an interval of 2 months between each interpretation. RESULTS: When the iPad Air™ screen was pure white, the contour lines revealed nonuniform luminance distribution. In the reading experiment, the areas under the curve of the medical monitor and the iPad Air™ were 0.9311 and 0.9431, respectively. No significant difference was observed between the medical monitor and the iPad Air™ (p = 0.113). CONCLUSION: The results of the observer performance studies for detecting acute ischemic cerebrovascular disorders on an iPad Air™ were found to be similar to those on a medical monitor.

Rupture of cerebral aneurysms often causes subarachnoid hemorrhage which is a life-threatening condition with high mortality rates. Larger aneurysms are believed to be more likely to rupture and should therefore be treated. Recently, flow diverters (FDs) are widely used to treat large or wide neck aneurysms. However, it can be difficult to treat them by deployment of a single FD because of its insufficient flow disturbance. To overcome this problem, double stenting technique is sometimes applied with the aim to improve the effect of blood velocity reduction. In this study, we used computational fluid dynamics (CFD) to investigate the hemodynamic changes in an aneurysm when deploying virtual FDs. The results showed that the characteristics of the blood flow field inside the aneurysm did not changed much after the deployment of a single FD but underwent a large change after the deployment of two FDs. Furthermore, the velocity reduction in the aneurysm sac at a plane away from the parent artery increased from 25.9% to 92.8% when two FDs were deployed instead of one compared to no stenting. Double stenting was effective to decrease blood velocity in large or wide neck aneurysms.

PURPOSE: A high packing density (PD) (i.e., coil volume per aneurysm volume) helps prevent recanalization after endosaccular embolization of cerebral aneurysms. We hypothesized that the use of soft coils may be useful to raise PD and retrospectively investigated the correlation between the ED coil volume rate (i.e., volume ratio of all placed coils) and PD in patients treated with endosaccular embolization using this coil. METHODS: Excluding aneurysms treated with a stent, 292 aneurysms treated using ED coils were included in this study. The 292 aneurysms and aneurysms with ≥30%, ≥40%, and ≥50% ED coil volume rates (202, 168, and 129 aneurysms, respectively) underwent linear regression analysis of the following seven factors' influence on PD:ED ratio, aneurysm volume, neck width, height, maximum diameter, dome-to-neck ratio, and aspect ratio. RESULTS: Independent factors of a high PD were high ED ratio and small neck width on analyses of aneurysms with an ED ratio of ≥40% and ≥50%. Only neck width was an independent factor on analyses of all 292 aneurysms and aneurysms with ED ratio of ≥30%. CONCLUSION: The use of ED coils in high volume rate correlated with a high PD and may contribute to prevent recanalization in small aneurysms.

Noncontrast computed tomography (NCCT) has been used for the detection of early ischemic change (EIC); however, correct interpretation of NCCT findings requires much clinical experience. This study aimed to assess the accuracy of time maximum intensity projection computed tomography technique (tMIP), which reflects the maximum value for the time phase direction from the dynamic volume data for each projected plane, for detection of EIC, against that of NCCT.Retrospective review of NCCT, cerebral blood volume in CT perfusion (CTP-CBV), and tMIP of 186 lesions from 280 regions evaluated by Alberta Stroke Program Early CT Score (ASPECTS) in 14 patients with acute middle cerebral artery stroke who had undergone whole-brain CTP using 320-row area detector CT was performed. Four radiologists reviewed EIC on NCCT, CTP-CBV, and tMIP in each ASPECTS region at onset using the continuous certainty factor method. Receiver operating characteristic analysis was performed to compare the relative performance for detection of EIC. The correlations were evaluated.tMIP-color showed the best discriminative value for detection of EIC. There were significant differences in the area under the curve for NCCT and tMIP-color, CTP-CBV (P < .05). Scatter plots of ASPECTS showed a positive significant correlation between NCCT, tMIP-gray, tMIP-color, and the follow-up study (NCCT, r = 0.32, P = .0166; tMIP-gray, r = 0.44, P = .0007; tMIP-color, r = 0.34, P = .0104).Because tMIP provides a high contrast parenchymal image with anatomical and vascular information in 1 sequential scan, it showed greater accuracy for detection of EIC and predicted the final infarct extent more accurately than NCCT based on ASPECTS.

When using detachable coils for cerebral aneurysm embolization, it is necessary to place a microcatheter with radiopaque markers at 2 sites (tip and 3 cm proximal from the tip) in most cases. Detachable coils that can be positioned independently from the proximal marker may facilitate new applications utilizing their characteristics. Herein, we report 2 cases that were treated with new applications. Detachable coils that function to electrically detect the moment they come out of the microcatheter were used. In one patient with a large aneurysm with an irregular shape, coil embolization was applied by advancing the catheter more than 3 cm from the aneurysm neck to the caudally protruded compartment near the proximal end of the neck, which was difficult to reach with the coil. In the other patient with cerebral arteriovenous malformation (AVM), microcatheters for AVM without a proximal marker were used for coil embolization before Onyx injection: Coil embolization was applied through one microcatheter to a site more proximal than the tip of the other microcatheter, followed by Onyx injection through the distal catheter, by which the nidus was continuously penetrated from the initiation of injection, obtaining an effect similar to that of the plug and push technique. Through the use of detachable coils, which are not dependent on the visibility of the proximal marker, the limitation of catheter positioning is reduced and the applicable types of catheter increase, which may facilitate to enable its use for new clinical indications.

Objective We aimed to clarify the cause of shortened mean transit time (MTT) in acute ischemic cerebrovascular disease and examined its relationship with reperfusion. Methods Twenty-three patients with acute ischemic cerebrovascular disease underwent whole-brain computed tomography perfusion (CTP). The maximum MTT (MTT max), minimum MTT (MTT min), ratio of maximum and minimum MTT (MTT min/max), and minimum cerebral blood volume (CBV) (CBV min) were measured by automatic region of interest analysis. Diffusion weighted image was performed to calculate infarction volume. We compared these CTP parameters between reperfusion and nonreperfusion groups and calculated correlation coefficients between the infarction core volume and CTP parameters. Results Significant differences were observed between reperfusion and nonreperfusion groups (MTT min/max: P = 0.014; CBV min ratio: P = 0.038). Regression analysis of CTP and high-intensity volume on diffusion weighted image showed negative correlation (CBV min ratio: r = -0.41; MTT min/max: r = -0.30; MTT min ratio: r = -0.27). Conclusions A region of shortened MTT indicated obstructed blood flow, which was attributed to the singular value decomposition method error.

<p>Objective: A case of cerebral embolism due to left atrial myxoma successfully treated using a direct aspiration first pass technique (ADAPT) is reported with a review of the literature.</p><p>Case Presentation: The patient was a 31-year-old male who developed left hemiparesis and dysarthria and was transported to our hospital. Based on MRI and MRA findings, a diagnosis of acute cerebral infarction due to occlusion of the distal part of M1 of the right middle cerebral artery, and transthoracic echocardiography suggested left atrial myxoma. Intravenous thrombolysis with recombinant tissue plasminogen activator (rt-PA) and mechanical thrombectomy were carried out, and complete recanalization could be achieved 196 minutes after the onset. The symptoms were resolved, and the embolus was pathologically confirmed to be left atrial myxoma.</p><p>Conclusion: ADAPT using Penumbra was suggested to be useful for the treatment of cardiogenic cerebral embolism due to left atrial myxoma.</p>

The safety and efficacy of emergency carotid artery stenting (CAS) for patients with acute ischemic stroke resulting from internal carotid artery stenosis are not established. In this retrospective study, we evaluated outcomes for CAS performed within 2 weeks of acute ischemic stroke for 16 patients treated between December 2009 and February 2014. Cases of internal carotid artery occlusion, internal carotid dissection, or intracranial major arterial trunk occlusion were excluded. Five patients were treated with CAS during the hyperacute phase (within 24 h of stroke onset), three in the advanced phase (within 24 h of stroke-in-evolution after admission), and eight in the acute phase (24 h to 2 weeks after onset). We evaluated modified Rankin scale (mRS) scores 90 days after CAS. For patients treated during the hyperacute phase without intravenous tissue-type plasminogen activator (IV-tPA), two had mRS scores of 2 and one had a score of 3. Two patients treated in the hyperacute phase with IV-tPA had scores of 5: one with symptomatic intracerebral hemorrhage and the other with acute brain swelling. For patients treated in the advanced phase, mRS scores were 1, 3, and 5; the patient with 5 had contralateral cerebral infarction. All patients treated in the acute phase had scores of 2 or lower. Patients treated with IV-tPA in advanced or acute phases had no severe post-CAS complications. CAS was effective and safe for treating ischemic stroke within 2 weeks of onset. However, IV-tPA treatment may be a risk factor for CAS treatment during the hyperacute phase.

2006年1月〜2015年5月迄に、発症後48時間以内の早期に根治的治療を行った前交通動脈瘤破裂によるクモ膜下出血(SAH)102例を対象に、破裂前交通動脈瘤の発育方向を中心に重症度と治療予後の関係について、後方視的に検討した。性別は男性41例(40.1%)、女性61例(59.8%)、年齢は31〜82歳(平均61.0±12.8歳)、治療内訳は脳動脈瘤頸部クリッピング術が63例、コイル塞栓術が39例であった。WFNS分類による102例の内訳はGr.I 5例、II 36例、III 16例、IV 17例、V 28例、瘤径の全体平均は5.5±0.3mmであった。重症SAH(Gr.IV〜V)が占める割合と瘤径において有意差を認めたが、脳内出血、脳室内出血、急性水頭症の合併、カテコールアミン値は各群間で有意差を認めなかった。予後良好率はsup.が88%と最も高値で、post.が33%と最も低値であったが、両群間に統計学的有意差は認めなかった。しかし、ant.はlat.と比べ有意に予後が良好で、ant.はinf.よりも予後がよい傾向がみられた。また、重症度と治療予後の比較において、重症度が高いにもかかわらず退院時予後がよい症例を「重症度と治療予後の乖離」と定義すると、そのような症例が計18例認められた。

Objective To improve bleeding management during brain tumor surgery, feeder arteries supplying the tumor are often embolized presurgically. However, access to feeder arteries can be limited, and embolization of feeders from internal carotid artery (ICA) branches often causes complications. We evaluated the PercuSurge GuardWire (Medtronic, Minneapolis, Minnesota, United States) system (PGWS) with aspiration catheter as amodification of the embolization technique used to block tumor-supplying branches of the ICA. Methods Two skull-base tumors were treated with preoperative embolization. One was a meningioma; the other was a hemangiopericytoma. In each case, the microcatheter could not be threaded into the ICA feeder arteries. Therefore, particulate embolic material was injected near the ICA branch while maintaining ICA balloon protection by the PGWS at the orifice of the ophthalmic artery. After embolization, we removed the remaining embolic material in the ICA using an aspiration catheter. In both cases, there were no postembolization complications and no high-intensity areas in the diffusion-weighted magnetic resonance image, and the tumorectomy proceeded as scheduled. Conclusion This modified technique may be a promising alternative for reducing embolic complications and improving the success rate, although case accumulation is needed to confirm this result.

BACKGROUND: In embolizing a cerebral aneurysm, achievement of a high-volume embolization ratio (VER: volume of inserted coils / aneurysm volume) is important because it may prevent coil compaction and recanalization. The goal of the study is to examine whether use of softer and longer coils gives an adequate VER with fewer coils, particularly for small aneurysms. METHODS: Aneurysm volumes, VERs, and numbers of inserted coils were investigated in 23 cases of small aneurysms embolized using Infini coils, a long soft coil with a primary diameter of 0.010 inches (Infini group). An aneurysm volume- and VER-matched control (non-Infini) group of 59 cases was selected from patients treated at our facility. Data were also compared between subgroups of patients (n = 18 and n = 34 in the Infini and non-Infini groups, respectively) who were not treated with thicker coils with primary diameters of 0.0135-0.015 inches (18-type coils), since these coils affect the number of coils by increasing VER rapidly. RESULTS: Average aneurysm volumes and VERs did not differ significantly between the Infini and non-Infini groups. Significantly fewer coils were used per 0.1 ml aneurysm volume in the Infini group (4.08 coils in average) compared with the non-Infini group (5.67) (p < 0.001). In the non-18-type subgroups, the number of coils used remained significantly smaller in the Infini group (4.49) compared with the non-Infini group (6.72), (p < 0.001). CONCLUSION: To achieve VER ≥20%, use of Infini coils significantly decreased the number of coils required per unit volume of a small aneurysm.

Objective: We compared cerebral blood flow (CBF) measured using computed tomographic (CT) perfusion (CTP) and N-isopropyl-p-[(123) I]-iodoamphetamine cerebral perfusion single-photon emission computed tomography (SPECT). Methods: We used a 320-row area detector CT and N-isopropyl-p-[(123) I]-iodoamphetamine cerebral perfusion SPECT under similar conditions in patients with chronic cerebrovascular disease. Images were automatically aligned 3-dimensionally for voxel-by-voxel comparisons. Results: Linear positive correlations were observed between CTP-CBF including high-blood-flow areas and SPECT-CBF over the whole brain (r = 0.001-0.6, P &lt; 0.01), superior cerebral level (r = 0.45-0.93, P &lt; 0.01), basal ganglia level (r = 0.44-0.77, P &lt; 0.01), and skull base (r = 0.02-0.66, P &lt; 0.01). Correlations between CTP-CBF excluding high-blood-flow areas were significantly higher (P &lt; 0.0001). Conclusions: Computed tomographic perfusion overestimated CBF compared with SPECT and showed poor correlation at the skull base. Computed tomographic perfusion CTP excluding high-blood-flow areas improved the correlation over the whole brain in patients with chronic cerebrovascular disease.

脳梗塞とクモ膜下出血を併発した前大脳動脈解離の1例を文献的考察と共に報告する。症例は既往に高血圧がある43歳女性。突然の失語・右片麻痺・意識障害を主訴に当院救急搬送された。来院時の頭部単純CTでクモ膜下出血を認め、造影CTでは左前大脳動脈領域のcerebral blood flow/cerebral blood volume低下と左A2描出不良を認めた。第1病日に施行されたDSAでは左recurrent artery of Heubner分岐直後から末梢にかけてpearl & string signを認め、以上の所見から梗塞・出血同時発症の左前大脳動脈解離と診断した。recurrent artery of Heubner領域の梗塞は生じていなかった。既に左前大脳動脈領域の梗塞巣が完成していた為、血行再建術は併用せずrecurrent artery of Heubnerを温存する形で血管内手術による母血管閉塞を施行した。術後は降圧による保存的治療を施行した。術後2週間のfollow up DSAで塞栓部近位側へ解離が進行している可能性が考えられたものの、recurrent artery of Heubner温存目的で追加塞栓は行わずにそのまま保存的治療を継続した。その後は解離の進行や再出血所見を認めず良好な経過を辿っている。前大脳動脈解離で脳梗塞とクモ膜下出血を併発する症例は稀であり、我々が調査し得た限りでは報告されているのは自験例を含めて16症例のみである。半数以上は保存的治療で良好な経過を辿っているが、同様の発症形式で外科的治療を必要とする再出血ハイリスク症例が存在する可能性がある。報告症例数の少ない現時点では困難だが、効果的な治療選択をする上で今後は症例の蓄積と共に再出血ハイリスク因子の同定が必要だと考えられた。(著者抄録)

The vascular type of Ehlers-Danlos syndrome (vEDS) is an autosomal dominant hereditary disease characterized by connective tissue fragility throughout the body, including the arteries, viscera, and gastrointestinal tract. We report a case in which we performed transvenous embolization (TVE) via direct superior ophthalmic vein (SOV) approach to treat a direct carotid-cavernous fistula (CCF) in a patient with Ehlers-Danlos syndrome (EDS). The patient was a 37-year-old woman who developed tinnitus in her left ear and a headache during examination in the outpatient clinic of another hospital in order to make a definitive diagnosis of vEDS, and she was referred to our hospital and examined. Based on the results of all of the studies she was diagnosed with a CCF. Conservative treatment was attempted, but was not very effective. Because of progressing aphasia, TVE was performed via the SOV direct cut. There were no intraoperative or postoperative complications. It has been reported that cerebral angiography is generally contraindicated in vEDS and that the morbimortality associated with endovascular treatment is very high. When performing treatment it is necessary to be sufficiently aware of the risks it entails.

【目的】妊婦に対する脳血管内治療には,放射線被曝や造影剤,抗血栓療法など,さまざまな問題が存在する.今回,人体ファントム(ランドファントム)を用いて下腹部被曝線量を測定し,胎児に与えうる放射線被曝の影響につき検討したので,自験例2例とともに報告する.【方法】ランドファントムと熱蛍光線量計素子を用いて,頭部血管造影(右上腕穿刺)・脳血管内治療に準じた透視・撮影を行い,生殖腺に相当する部位における被曝線量を計測した.【結果】頭部(外後頭隆起周辺)で最大約800mGy程度の被曝線量に対し,生殖腺相当部位の下腹部における被曝線量は平均0.05mGy程度であり,妊娠中であっても胎児に与える影響は極めて低いことが予想される結果であった.【結論】妊婦に対する脳血管内治療に対して胎児に生じる被曝の影響は極めて低いと考えられた.妊娠中の脳血管内治療には,被曝以外にもさまざまな問題はあるものの,諸注意点に留意すれば安全かつ有効に治療を行うことが可能と考えられる.(著者抄録)