Tumor Embolization via the Meningohypophyseal and Inferolateral Trunk in Patients with Skull Base Tumors Using the Distal Balloon Protection Technique.

Background And Purpose: Tumor embolization through the meningohypophyseal trunk and inferolateral trunk is known to be effective in skull base 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 the 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.

Development of a Model for Plaque Induction in Rat Carotid Arteries.

 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.

Risk of postoperative scalp necrosis in the occipital artery region after posterior cranial fossa surgery.

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.

Carotid Plaque Diagnosis With 3-Dimensional Computed Tomography Angiography: A Comparison With Magnetic Resonance Imaging-Based Plaque Diagnosis.

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.

Intraoperative Real-Time Near-Infrared Image-Guided Endoscopic Endonasal Surgery for Pituitary Tumors.

Background: For endoscopic endonasal surgery of pituitary tumors, tissue identification and intraoperative judgment depend largely on surgeon expertise. In the present study, we assess whether the delayed-window indocyanine green (ICG) technique can identify pituitary gland tumors in real-time during surgery and analyze the mechanism of ICG fluorescence in the pituitary gland and tumor.

Methods: Twenty-five patients with a pituitary adenoma were administered 12.

Uncertainty quantification in cerebral circulation simulations focusing on the collateral flow: Surrogate model approach with machine learning.

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.

Relationship between epicardial adipose tissue and coronary artery stenoses on computed tomography in patients scheduled for carotid artery revascularization.

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.

Computational fluid dynamic analysis of the initiation of cerebral aneurysms.

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.

Hemodynamic Investigation of the Effectiveness of a Two Overlapping Flow Diverter Configuration for Cerebral Aneurysm Treatment.

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.

Transvenous Embolization of Cavernous Sinus Dural Arteriovenous Fistula through the Angiographically Occlusive Superior Ophthalmic Vein.

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.

Reduction of thromboembolic complications during the endovascular treatment of unruptured aneurysms by employing a tailored dual antiplatelet regimen using aspirin and prasugrel.

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.

Objective and quantitative evaluation of angiographic vascularity in meningioma: parameters of dynamic susceptibility contrast-perfusion-weighted imaging as clinical indicators of preoperative embolization.

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.

A penalized spline fitting method to optimize geometric parameters of arterial centerlines extracted from medical images.

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.

Initial clinical experience of a prototype ultra-high-resolution CT for assessment of small intracranial arteries.

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.

Hemodynamic Change In A Cerebral Aneurysm Treated By Double Stenting Technique.

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.

Reliability of diagnosing acute ischemic cerebrovascular on magnetic resonance imaging disorders using iPads.

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.

Relationship between the Volume Rate of Ed Coil (Ed Ratio) and Packing Density in Endosaccular Embolization of Cerebral Aneurysms.

Purpose: A high packing density (PD) (i.e., coil volume per aneurysm volume) helps prevent recanalization after endosaccular embolization of cerebral aneurysms.

Susceptibility-Weighted Imaging of Deep Venous Congestion in Petroclival Meningioma.

Background: Protecting the venous drainage route during surgery in cases of petroclival meningioma (PCM) is important. Identifying venous congestion preoperatively can be valuable in reducing the risks associated with venous congestion during surgery. In this study, we examined the utility of susceptibility-weighted imaging (SWI) in identifying the presence of venous congestion in PCM cases preoperatively and identified the factors associated with it.

Use of Detachable Coils Without the Need of a Double Marker Microcatheter: Technical Note.

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.

Preliminary study of time maximum intensity projection computed tomography imaging for the detection of early ischemic change in patient with acute ischemic stroke.

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.

Noninvasive Assessment of Stenotic Severity and Plaque Characteristics by Coronary CT Angiography in Patients Scheduled for Carotid Artery Revascularization.

Aims: Coronary artery atherosclerosis in patients needing carotid revascularization has not been fully clarified. The aim of this study was to evaluate the stenotic severity and plaque characteristics of coronary arteries by coronary computed tomography angiography (CTA) in patients scheduled for carotid-artery stenting (CAS) or carotid endarterectomy (CEA).

Methods: We performed coronary CTA after carotid ultrasound (US) in 164 patients (81.

Carotid stenting for unilateral stenosis can increase contralateral hemispheric cerebral blood flow.

Background: The revascularization of carotid stenosis can increase ipsilateral cerebral blood flow (CBF). Occasionally, elevated CBF is also evident on the contralateral side, but this phenomenon is poorly understood.

Objective: To analyze retrospectively the relationship between a contralateral CBF increase and several clinical and radiologic features.