scholarly journals Microdistribution of Magnetic Resonance Imaging Contrast Agents in Atherosclerotic Plaques Determined by LA-ICP-MS and SR-μXRF Imaging

2020 ◽  
Author(s):  
Yavuz Oguz Uca ◽  
David Hallmann ◽  
Bernhard Hesse ◽  
Christian Seim ◽  
Nicola Stolzenburg ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Atherosclerotic Plaque ◽  
Vessel Wall ◽  
Matrix Material ◽  
Arterial Calcification ◽  
Atherosclerotic Plaques ◽  
Elemental Distribution ◽  
Resonance Imaging ◽  
Icp Ms

Abstract Purpose Contrast-enhanced magnetic resonance imaging (MRI) has the potential to replace angiographic evaluation of atherosclerosis. While studies have investigated contrast agent (CA) uptake in atherosclerotic plaques, exact CA spatial distribution on a microscale is elusive. The purpose of this study was to investigate the microdistribution of gadolinium (Gd)- and iron (Fe) oxide-based CA in atherosclerotic plaques of New Zealand White rabbits. Procedures The study was performed as a post hoc analysis of archived tissue specimens obtained in a previous in vivo MRI study conducted to investigate signal changes induced by very small superparamagnetic iron oxide nanoparticles (VSOP) and Gd-BOPTA. For analytical discrimination from endogenous Fe, VSOP were doped with europium (Eu) resulting in Eu-VSOP. Formalin-fixed arterial specimens were cut into 5-μm serial sections and analyzed by immunohistochemistry (IHC: Movat’s pentachrome, von Kossa, and Alcian blue (pH 1.0) staining, anti-smooth muscle cell actin (anti-SMA), and anti-rabbit macrophage (anti-RAM-11) immunostaining) and elemental microscopy with laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and synchrotron radiation μX-ray fluorescence (SR-μXRF) spectroscopy. Elemental distribution maps of Fe, Eu, Gd, sulfur (S), phosphorus (P), and calcium (Ca) were investigated. Results IHC characterized atherosclerotic plaque pathomorphology. Elemental microscopy showed S distribution to match the anatomy of arterial vessel wall layers, while P distribution corresponded well with cellular areas. LA-ICP-MS revealed Gd and Fe with a limit of detection of ~ 0.1 nmol/g and ~ 100 nmol/g, respectively. Eu-positive signal identified VSOP presence in the vessel wall and allowed the comparison of Eu-VSOP and endogenous Fe distribution in tissue sections. Extracellular matrix material correlated with Eu signal intensity, Fe concentration, and maximum Gd concentration. Eu-VSOP were confined to endothelium in early lesions but accumulated in cellular areas in advanced plaques. Gd distribution was homogeneous in healthy arteries but inhomogeneous in early and advanced plaques. SR-μXRF scans at 0.5 μm resolution revealed Gd hotspots with increased P and Ca concentrations at the intimomedial interface, and a size distribution ranging from a few micrometers to submicrometers. Conclusions Eu-VSOP and Gd have distinct spatial distributions in atherosclerotic plaques. While Eu-VSOP distribution is more cell-associated and might be used to monitor atherosclerotic plaque progression, Gd distribution indicates arterial calcification and might help in characterizing plaque vulnerability.

scholarly journals Understanding the Clinical Implications of Intracranial Arterial Calcification Using Brain CT and Vessel Wall Imaging

2021 ◽  
Vol 12 ◽  
Author(s):  
Wen-Jie Yang ◽  
Bruce A. Wasserman ◽  
Lu Zheng ◽  
Zhong-Qing Huang ◽  
Jia Li ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Vessel Wall ◽  
Ct Images ◽  
Arterial Calcification ◽  
Atherosclerotic Plaques ◽  
Stable Form ◽  
Resonance Imaging ◽  
Plaque Stability ◽  
Intracranial Artery Stenosis

Background and Purpose: Intracranial arterial calcification (IAC) has been the focus of much attention by clinicians and researchers as an indicator of intracranial atherosclerosis, but correlations of IAC patterns (intimal or medial) with the presence of atherosclerotic plaques and plaque stability are still a matter of debate. Our study aimed to assess the associations of IAC patterns identified on computed tomography (CT) with the presence of plaque detected on vessel wall magnetic resonance imaging and plaque stability.Materials and Methods: Patients with stroke or transient ischemic attack and intracranial artery stenosis were recruited. IAC was detected and localized (intima or media) on non-contrast CT images. Intracranial atherosclerotic plaques were identified using vessel wall magnetic resonance imaging and matched to corresponding CT images. Associations between IAC patterns and culprit atherosclerotic plaques were assessed by using multivariate regression.Results: Seventy-five patients (mean age, 63.4 ± 11.6 years; males, 46) were included. Two hundred and twenty-one segments with IAC were identified on CT in 66 patients, including 86 (38.9%) predominantly intimal calcifications and 135 (61.1%) predominantly medial calcifications. A total of 72.0% of intimal calcifications coexisted with atherosclerotic plaques, whereas only 10.2% of medial calcifications coexisted with plaques. Intimal calcification was more commonly shown in non-culprit plaques than culprit plaques (25.9 vs. 9.4%, P = 0.008). The multivariate mixed logistic regression adjusted for the degree of stenosis showed that intimal calcification was significantly associated with non-culprit plaques (OR, 2.971; 95% CI, 1.036–8.517; P = 0.043).Conclusion: Our findings suggest that intimal calcification may indicate the existence of a stable form of atherosclerotic plaque, but plaques can exist in the absence of intimal calcification especially in the middle cerebral artery.

Animal models of atherosclerosis and magnetic resonance imaging for monitoring plaque progression

Vascular ◽  
2014 ◽  
Vol 22 (3) ◽  
pp. 221-237 ◽  
Author(s):  
Antoine Millon ◽  
Emmanuelle Canet-Soulas ◽  
Loic Boussel ◽  
Zahi Fayad ◽  
Philippe Douek
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Animal Models ◽  
Atherosclerotic Plaque ◽  
Atherosclerotic Plaques ◽  
Resonance Imaging ◽  
Human Atherosclerotic Plaque ◽  
Clinical Events ◽  
Vulnerable Plaques

Atherosclerosis, the main cause of heart attack and stroke, is the leading cause of death in most modern countries. Preventing clinical events depends on a better understanding of the mechanism of atherosclerotic plaque destabilization. Our knowledge on the characteristics of vulnerable plaques in humans has grown past decades. Histological studies have provided a precise definition of high-risk lesions and novel imaging methods for human atherosclerotic plaque characterization have made significant progress. However the pathological mechanisms leading from stable lesions to the formation of vulnerable plaques remain uncertain and the related clinical events are unpredictable. An animal model mimicking human plaque destablization is required as well as an in vivo imaging method to assess and monitor atherosclerosis progression. Magnetic resonance imaging (MRI) is increasingly used for in vivo assessment of atherosclerotic plaques in the human carotids. MRI provides well-characterized morphological and functional features of human atherosclerotic plaque which can be also assessed in animal models. This review summarizes the most common species used as animal models for experimental atherosclerosis, the techniques to induce atherosclerosis and to obtain vulnerable plaques, together with the role of MRI for monitoring atherosclerotic plaques in animals.

scholarly journals Value of vessel wall magnetic resonance imaging in the diagnosis of cerebrovascular diseases

2020 ◽  
Vol 56 (1) ◽  
Author(s):  
Sherien Farag ◽  
Hany Zaki El-Dien ◽  
Yasser Abdelazeem ◽  
Mohammed Khaled Elewa ◽  
Khaled Abdelmaksoud ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Atherosclerotic Plaque ◽  
Vessel Wall ◽  
Resonance Imaging ◽  
Stroke Patients ◽  
Post Contrast ◽  
Intracranial Vessel ◽  
Stenotic Lesions

Abstract Background Intracranial vessel wall imaging can detect non-stenotic lesions with further characterization of stenotic lesions that have already been detected with common angiographic methods. Magnetic resonance imaging (MRI) of the intracranial vessel wall can describe the presence of both large and small atherosclerotic lesions and to characterize the lesions based on enhancement, plaque content, and vulnerability Objectives To assess suspicious lesions detected by magnetic resonance angiography for further evaluation by vessel wall MRI. Methods A total of sixteen ischemic stroke patients within 2 weeks from onset were recruited to this cross-sectional study. Magnetic resonance angiography was done to document intracranial arterial stenosis. Further high-field MR unit (3 Tesla MRI Scanner) was used to obtain vessel wall MR sequences (T1 pre-post contrast and T2 fat sat) to differentiate between intracranial atherosclerotic plaque, vasculitis, and moyamoya disease and to assess atherosclerotic plaque activity (vulnerability) Results Vessel wall MR imaging showed arterial wall thickening with irregular inner margin and eccentric enhancement in cases of intracranial atherosclerosis, where as in case of CNS vasculitis, it showed circumferential wall enhancement with regular smooth inner margin. In cases of moyamoya disease, the vessel wall MR showed a narrowing of the luminal artery without post-contrast enhancement of the wall, no hemorrhagic nor fatty content. Conclusion Vessel wall MR imaging is recommended for stroke patients with suspected intracranial large vessel atherosclerosis seen in MRA to assess atherosclerotic plaque activity and characterization of stenotic lesions

scholarly journals High-Resolution Vessel Wall Magnetic Resonance Imaging of Small Unruptured Intracranial Aneurysms

2021 ◽  
Vol 10 (2) ◽  
pp. 225
Author(s):  
Łukasz Zwarzany ◽  
Ernest Tyburski ◽  
Wojciech Poncyljusz
Keyword(s):  
Magnetic Resonance Imaging ◽  
Risk Factors ◽  
Magnetic Resonance ◽  
High Resolution ◽  
Vessel Wall ◽  
Intracranial Aneurysms ◽  
Aneurysm Rupture ◽  
Resonance Imaging ◽  
Aneurysm Wall ◽  
Conventional Risk Factors

Background: We decided to investigate whether aneurysm wall enhancement (AWE) on high-resolution vessel wall magnetic resonance imaging (HR VW-MRI) coexists with the conventional risk factors for aneurysm rupture. Methods: We performed HR VW-MRI in 46 patients with 64 unruptured small intracranial aneurysms. Patient demographics and clinical characteristics were recorded. The PHASES score was calculated for each aneurysm. Results: Of the 64 aneurysms, 15 (23.4%) showed wall enhancement on post-contrast HR VW-MRI. Aneurysms with wall enhancement had significantly larger size (p = 0.001), higher dome-to-neck ratio (p = 0.024), and a more irregular shape (p = 0.003) than aneurysms without wall enhancement. The proportion of aneurysms with wall enhancement was significantly higher in older patients (p = 0.011), and those with a history of prior aneurysmal SAH. The mean PHASES score was significantly higher in aneurysms with wall enhancement (p < 0.000). The multivariate logistic regression analysis revealed that aneurysm irregularity and the PHASES score are independently associated with the presence of AWE. Conclusions: Aneurysm wall enhancement on HR VW-MRI coexists with the conventional risk factors for aneurysm rupture.

scholarly journals Magnetic resonance imaging of experimental atherosclerotic plaque: Comparison of two ultrasmall superparamagnetic particles of iron oxide

2006 ◽  
Vol 24 (2) ◽  
pp. 388-393 ◽  
Author(s):  
Christoph U. Herborn ◽  
Florian M. Vogt ◽  
Thomas C. Lauenstein ◽  
Olaf Dirsch ◽  
Claire Corot ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Iron Oxide ◽  
Magnetic Resonance ◽  
Atherosclerotic Plaque ◽  
Resonance Imaging ◽  
Superparamagnetic Particles

scholarly journals Standard-Dose Atorvastatin Treatment in Patients With Symptomatic Middle Cerebral Artery Atherosclerotic Stenosis: A Vessel Wall Magnetic Resonance Imaging Study

2021 ◽  
Vol 12 ◽  
Author(s):  
Yejun Wu ◽  
Fangbing Li ◽  
Yilin Wang ◽  
Tianxiang Hu ◽  
Honghua Gao
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Vessel Wall ◽  
Standard Dose ◽  
Density Lipoprotein ◽  
Statin Treatment ◽  
Resonance Imaging ◽  
Atorvastatin Treatment ◽  
Atherosclerotic Stenosis

Background and Purpose: Ischemic stroke can be caused by atherosclerotic lesions of the middle cerebral artery (MCA). Some studies have described the effects of statin treatment on carotid artery plaques, but little is known about the effects of statin treatment on MCA plaques. The purpose of this study was to validate the efficacy of standard-dose atorvastatin (20 mg/day) in patients with symptomatic MCA atherosclerotic stenosis (SMAS) in northern China.Materials and Methods: This study is a prospective, single-arm, single-center, 12-month follow-up observational study monitoring imaging, and clinical outcomes of standard-dose atorvastatin treatment among patients with SMAS. The primary outcomes were changes in vessel wall magnetic resonance imaging (VWMRI) and serum lipid profiles before and after (1, 3, 6, and 12 months) statin treatment.Results: A total of 46 patients were recruited for this study, and 24 patients completed the follow-up. During the follow-up period, serum non-high-density lipoprotein cholesterol concentrations gradually decreased in the patients. Fourteen patients (54.33%) had a reversal of MCA plaques and 10 patients (41.67%) had no significant progression of MCA plaques and remained stable at the follow-up endpoint. At the 12 months follow-up time-point, the treatment did not reverse vascular remodeling or change the shape and distribution of plaques. Altered serum low-density lipoprotein cholesterol (LDL-C) concentrations in patients were strongly associated with plaque reversal.Conclusion: Vessel wall magnetic resonance imaging could accurately characterize changes in MCA plaques after lipid-lowering therapy. Standard-dose atorvastatin treatment could stabilize and reverse plaques in northern Chinese patients with SMAS.

High resolution vessel wall magnetic resonance imaging in HIV associated vasculopathy

2017 ◽  
Vol 381 ◽  
pp. 421-422
Author(s):  
G. Taricani Kubota ◽  
R. de Faria Ferreira ◽  
T. Rocha Figueiredo ◽  
G. Titoneli dos Santos ◽  
L. Martins Tavares Scianni Morais ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
High Resolution ◽  
Vessel Wall ◽  
Resonance Imaging
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