Intraplaque hemorrhage volume in patients with carotid atherosclerosis: How informative is it?

Background And Purpose: Intraplaque hemorrhage (IPH) of carotid atherosclerosis is an important feature in complex lesions preceding acute stroke events. The current study aimed to determine the role played by IPH volume compared to that of carotid stenosis or maximal wall thickness in patients with carotid IPH.

Materials And Methods: This retrospective study included 233 patients who presented with carotid IPH on vessel wall imaging (VWI).

Geometric changes and clinical risk factors from aortic arch to proximal internal carotid artery between normal subjects and moderate right carotid plaques.

The anatomical features spanning from the aortic arch to the proximal carotid artery and the associated cardiovascular risks might significantly influence the development of right carotid plaque. Our research aimed to compare these anatomical and risk factors between individuals with no carotid plaque and those with moderate right-side carotid plaque within a Korean cohort. We conducted a retrospective, cross-sectional analysis involving 413 participants, categorized into a normal group (n = 339) and a right moderate carotid plaque group (defined as > 50% stenosis based on NASCET criteria) (n = 74).

Quantification of steal flow on Doppler ultrasound in patients with arteriovenous graft for hemodialysis.

Purpose: Arteriovenous fistula (AVF) is the preferred treatment for long-term hemodialysis patients to allow reliable vascular access. Arteriovenous graft (AVG) is monitored using Doppler sonography to check a vessel's condition and predict complications such as steal syndrome. In this study, we developed an analysis algorithm and method to quantify steal syndrome using Doppler sonography.

Noninvasive wearable sensor for the continuous monitoring of human sound and movement signals in real-time.

Recently, with the development of non-invasive human health monitoring technology including wearable devices, a flexible sensor that monitors 'human sound and movement signals' such as human voice and muscle movement is attracting attention. In this experiment, electrospun nanofibers were mixed with highly conductive nanoparticles and coated with polyaniline to detect the patient's electrical signals. Due to the high piezoelectric effect, nanofiber-based sensors do not require charging through a separate battery, so they can be used as self-powered devices.

Validation of Signal Intensity Gradient from TOF-MRA for Wall Shear Stress by Phase-Contrast MR.

To validate the correlation between the signal intensity gradient (SIG) from time-of-flight magnetic resonance angiography (TOF-MRA) and wall shear stress (WSS) determined by phase contrast magnetic resonance (PC-MR), we conducted both experimental and human studies. In the experimental study, we measured WSS in four tubes of different sizes with variable flow rates using PC-MR and TOF-MRA. The flow rates of water in the experimental study ranged from 0.

Findings of Angiography and Carotid Vessel Wall Imaging Associated with Post-Procedural Clinical Events after Carotid Artery Stenting.

Purpose: Vessel wall imaging (VWI) for carotid plaque is better for detecting unstable carotid plaque such as intraplaque hemorrhage (IPH), lipid-rich necrotic core (LRNC), and thin/ruptured fibrous cap. However, the role of VWI before carotid artery stenting (CAS) is unclear. Thus, this study aimed to determine the findings of symptomatic carotid stenosis before CAS on angiography and carotid VWI and to evaluate the imaging findings associated with post-procedural clinical events after CAS.

Post-diffusion and perfusion magnetic resonance imaging of emboli to distal territories after endovascular thrombectomy.

Background And Purpose: This study aimed to investigate the clinical outcomes of emboli to distal territories (EDT) after aspiration thrombectomy in patients with acute anterior circulation occlusion.

Materials And Methods: From January 2016 to December 2022, all eligible patients who underwent endovascular treatment (EVT) due to acute anterior circulation occlusion were retrospectively reviewed. During this period, patients with EDT after EVT underwent magnetic resonance (MR) perfusion with angiography and diffusion-weighted imaging within 12 hours from recanalization.

Geometric versus Hemodynamic Indexes for Rupture-Destined Aneurysms: A Retrospective Cohort and a Repeated-Measures Study.

Introduction: A proper stratification of intracranial aneurysms is critical in identifying rupture-destined aneurysms and unruptured intracranial aneurysms. We aimed to determine the utility of geometric and hemodynamic indexes in differentiating two types of aneurysms and to examine the characteristics of natural evolutionary changes of unruptured aneurysms.

Methods: Rupture-destined aneurysm refers to an aneurysm that undergoes subsequent aneurysmal subarachnoid hemorrhage (SAH).

Strong Contrast Stagnation of Unilateral Vertebral Artery on Three-Dimensional Black Blood-Enhanced MRI Predicts Acute Medulla Infarction.

Purpose: This study aimed to evaluate angiographic and contrast enhancement (CE) patterns on three-dimensional (3D) black blood (BB) contrast-enhanced MRI in patients with acute medulla infarction.

Materials And Methods: From January 2020 to August 2021, we retrospectively analyzed stroke 3D BB contrast-enhanced magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) findings of patients visiting the emergency room for symptom evaluation of acute medulla infarction. In total, 28 patients with acute medulla infarction were enrolled in this study.

Aberrant Origin of the Distal Anterior Cerebral Artery from the Middle Cerebral Artery Related to Obstruction of Bilateral Proximal Anterior Cerebral Arteries: A Case Report.

Background: Aberrant origin of the distal anterior cerebral artery (ACA) arising from the middle cerebral artery (MCA) is extremely rare.

Case Presentation: A 74-year-old woman with a sudden onset of left-sided weakness was admitted to the emergency department. Angiography revealed an unusual course of the distal ACA originating from the MCA with bilateral obstruction of the proximal segment of the ACA and simultaneous occurrence of infarction in the ACA and MCA territories.

The comprehensive comparison of imaging sign from CT angiography and noncontrast CT for predicting intracranial hemorrhage expansion: A comparative study.

Expansion of intracranial hemorrhage (ICH) is an important predictor of poor clinical outcomes. Various imaging markers on non-contrast computed tomography (NCCT) or computed tomographic angiography (CTA) have been reported as predictors of ICH expansion. We aimed to compare the associations between various CT imaging markers and ICH expansion.

Comparison of imaging findings on three-dimensional black-blood enhanced MR imaging between intracranial atherosclerotic occlusion and thrombotic occlusion.

Purpose: The purpose of this study was to compare the imaging findings on three-dimensional (3D) black-blood (BB) contrast-enhanced MR imaging between intracranial atherosclerotic occlusion (IAO) and thrombotic occlusion (TO) of the middle cerebral artery (MCA) territory.

Materials And Methods: From August 2020 to September 2021, we retrospectively reviewed the BB contrast-enhanced MR imaging of patients visiting the emergency room for evaluation of acute ischemic stroke. In total, 77 patients with complete occlusion of the MCA territory on 3D BB contrast-enhanced MR imaging and cerebral angiography were enrolled in this study.

Acute Distal Vertebral Artery Occlusion in Patients with Asymmetrical Vertebral Artery Geometry: Role of Black-Blood-Enhanced MR Imaging.

Background: The purpose of this study was to evaluate the diagnostic value of contrast enhancement in a unilateral distal vertebral artery (VA) using black blood (BB)-enhanced magnetic resonance (MR) imaging in patients with acute neurological symptoms and asymmetrical VA geometry. Methods: From January 2020 to August 2021, we retrospectively analyzed BB-contrast-enhanced MR imaging and MR angiography (MRA) findings in stroke patients visiting the emergency room for an evaluation of acute neurological symptoms. We classified four patterns according to asymmetrical VA geometry using MRA and contrast enhancement using BB-enhanced MR imaging: type 1 = enhanced VA + no visualization of VA, type 2 = enhanced VA + hypoplastic VA, type 3 = non-enhanced VA + hypoplastic VA, or type 4 = non-enhanced VA + no visualization of VA.

Prevalence of Symptomatic Nonstenotic Carotid Disease Using Simultaneous Non-Contrast Angiography and Intraplaque Hemorrhage Imaging for MR Screen Protocol.

Background: To determine the prevalence of symptomatic nonstenotic carotid disease (SyNC) using simultaneous non-contrast angiography and intraplaque hemorrhage (SNAP) imaging for patients with acute stroke as an MR screen protocol and to assess imaging findings of carotid plaques. Patients and Methods: From May 2020 to October 2021, 2459 patients with suspected acute neurological symptoms were evaluated with brain diffusion-weighted imaging (DWI) and carotid SNAP imaging. We analyzed the degree of stenosis and intraplaque hemorrhage (IPH) using SNAP imaging.

The role of vessel wall imaging in determining the best treatment approach for coexisting aneurysms and subarachnoid hemorrhage.

Purpose: The purpose of this study was to investigate the utilization of gadolinium enhancement on vessel wall imaging (VWI) in treatment decision-making for patients with two intracranial aneurysms presenting as a subarachnoid hemorrhage (SAH).

Materials And Methods: We prospectively performed VWI using 3.0-Tesla (3T) magnetic resonance imaging (MRI) before treatment with endovascular coiling or surgical clipping in patients with one or two intracranial aneurysms.

Bilateral carotid artery geometry using magnetic resonance angiography: a 10-year longitudinal single center study.

Aging and atherosclerotic progression can lead to geometric changes in the carotid arteries. We conducted a longitudinal study to investigate geometric changes in the bilateral carotid arteries. We conducted a retrospective study of 177 subjects who underwent carotid contrast-enhanced magnetic resonance angiography (MRA) at our clinic at baseline and 10 years after the procedure.

Improving Blood Flow Visualization of Recirculation Regions at Carotid Bulb in 4D Flow MRI Using Semi-Automatic Segmentation with ITK-SNAP.

Assessment of carotid bulb hemodynamics using four-dimensional (4D) flow magnetic resonance imaging (MRI) requires accurate segmentation of recirculation regions that is frequently hampered by limited resolution. This study aims to improve the accuracy of 4D flow MRI carotid bulb segmentation and subsequent recirculation regions analysis. Time-of-flight (TOF) MRI and 4D flow MRI were performed on bilateral carotid artery bifurcations in seven healthy volunteers.

Evaluation of Plaque Vulnerability via Combination of Hemodynamic Analysis and Simultaneous Non-Contrast Angiography and Intraplaque Hemorrhage (SNAP) Sequence for Carotid Intraplaque Hemorrhage.

The purpose of this study was to assess the vulnerability of plaque using a combination of simultaneous non-contrast angiography, intraplaque hemorrhage (SNAP) sequence, and local hemodynamic analysis in an intraplaque hemorrhage (IPH), and to evaluate the association between morphological and hemodynamic factors and IPH by comparing the IPH (presence of IPH) and non-IPH (plaque with absence of IPH) groups. In total, 27 IPH patients and 27 non-IPH patients were involved in this study, and baseline characteristics were collected. For morphological factors, diameters, and areas of the internal carotid artery (ICA), external carotid artery, and common carotid artery were measured, and bifurcation angle (α) and ICA angle (β) were also measured for comparison between the IPH group and non-IPH group.

Analysis of Morphological-Hemodynamic Risk Factors for Aneurysm Rupture Including a Newly Introduced Total Volume Ratio.

The purpose of this study was to evaluate morphological and hemodynamic factors, including the newly developed total volume ratio (TVR), in evaluating rupture risk of cerebral aneurysms using ≥7 mm sized aneurysms. Twenty-three aneurysms (11 unruptured and 12 ruptured) ≥ 7 mm were analyzed from 3-dimensional rotational cerebral angiography and computational fluid dynamics (CFD). Ten morphological and eleven hemodynamic factors of the aneurysms were qualitatively and quantitatively compared.

Differential Diagnosis of Intraplaque Hemorrhage and Dissection on High-Resolution MR Imaging in Patients with Focal High Signal of the Vertebrobasilar Artery on TOF Imaging.

Purpose: Intraplaque hemorrhage (IPH) and dissection in the vertebrobasilar artery (VBA) on time of flight (TOF) source imaging are seen as focal eccentric high-signal intensity. The purpose of this study is to identify IPH and dissection in the VBA using high-resolution magnetic resonance imaging (HR-MRI).

Methods: A total of 78 patients (VBA IPH: 55; dissection: 23) with focal high-signal intensity in the VBA on simultaneous non-contrast angiography and intraplaque hemorrhage (SNAP) of HR-MRI were included in this study.

One-step evaluation of intraplaque hemorrhage in the carotid artery and vertebrobasilar artery using simultaneous non-contrast angiography and intraplaque hemorrhage.

Purpose: To investigate the one-step detection of intraplaque hemorrhage (IPH) in the carotid artery (CA) and vertebrobasilar artery (VBA) using simultaneous non-contrast angiography and intraplaque hemorrhage (SNAP).

Methods: From January 2019 to March 2020, 1820 consecutive patients who visited our emergency room for evaluation of neurologic symptoms underwent brain MR imaging, including the SNAP sequence. SNAP imaging examined the coronal section from the CA to the VBA.

Comparison of Hemodynamic Visualization in Cerebral Arteries: Can Magnetic Resonance Imaging Replace Computational Fluid Dynamics?

A multimodality approach was applied using four-dimensional flow magnetic resonance imaging (4D flow MRI), time-of-flight magnetic resonance angiography (TOF-MRA) signal intensity gradient (SIG), and computational fluid dynamics (CFD) to investigate the 3D blood flow characteristics and wall shear stress (WSS) of the cerebral arteries. TOF-MRA and 4D flow MRI were performed on the major cerebral arteries in 16 healthy volunteers (mean age 34.7 ± 7.