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

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.

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

Molecular Imaging and Biology ◽

10.1007/s11307-020-01563-z ◽

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.

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

Journal of Clinical Medicine ◽

10.3390/jcm10020225 ◽

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.

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High-Resolution Vessel Wall Magnetic Resonance Imaging in Angiogram-Negative Non-Perimesencephalic Subarachnoid Hemorrhage

Clinical Neuroradiology ◽

10.1007/s00062-015-0484-x ◽

2015 ◽

Vol 27 (2) ◽

pp. 175-183 ◽

Cited By ~ 12

Author(s):

J. M. Coutinho ◽

R. H. Sacho ◽

J. D. Schaafsma ◽

R. Agid ◽

T. Krings ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Subarachnoid Hemorrhage ◽

Magnetic Resonance ◽

High Resolution ◽

Vessel Wall ◽

Resonance Imaging ◽

Perimesencephalic Subarachnoid Hemorrhage

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

Frontiers in Neurology ◽

10.3389/fneur.2021.693397 ◽

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.

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High resolution vessel wall magnetic resonance imaging in HIV associated vasculopathy

Journal of the Neurological Sciences ◽

10.1016/j.jns.2017.08.3403 ◽

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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Abstract TP400: The Differences of Vessel Wall Features Between the Anterior and Posterior Brain Arteries Detected by High Resolution Magnetic Resonance Imaging in Patients With Acute Ischemic Stroke

Stroke ◽

10.1161/str.51.suppl_1.tp400 ◽

2020 ◽

Vol 51 (Suppl_1) ◽

Author(s):

Xiangyan Chen ◽

Lu Zheng ◽

Jia LI ◽

Wenjie Yang

Keyword(s):

Magnetic Resonance Imaging ◽

Ischemic Stroke ◽

Magnetic Resonance ◽

High Resolution ◽

Acute Ischemic Stroke ◽

Vessel Wall ◽

Posterior Circulation ◽

Intraplaque Hemorrhage ◽

Resonance Imaging ◽

Anterior Circulation

Backgrounds: The purpose of this study was to investigate vessel wall features visualization by high resolution magnetic resonance imaging (HRMRI) in a series of ischemic stroke patients and to identify differences between lesions in the anterior and posterior circulation. Methods: We consecutively recruited Chinese patients with acute ischemic stroke or transient ischemic attack from 2016 to 2018. All patients were scanned at 3T magnetic resonance imaging. We evaluated pre-and post-contrast cross-sectional views of M1 and M2 segments of middle cerebral arteries (MCAs), basilar arteries (BA) and V4 segments of vertebral arteries (VAs). Results: A total of 74 patients (males 52.3%; median age 62 years old) were included in this study, among which, 234 lesions were identified on HRMRI, including 117 MCA lesions, 26 BA lesions, and 91 VA lesions. The sensitivity and specificity of MRA for diagnosing stenosis in anterior circulation were 89.3% (95% CI, 81.8%- 94.2%) and 50.0 (95% CI, 9.2%- 90.8%). The sensitivity and specificity of MRA for diagnosing stenosis in posterior circulation were 73.2% (95% CI, 63.9%- 80.9%) and 40.0 (95% CI, 7.3%- 83.0%). VA had a significantly higher contrast enhancement index (43.71± 7.74, p <0.016) than MCA (23.32± 2.46) or BA (22.69± 5.31) . Anterior circulation plaques had higher degree of stenosis (anterior versus posterior: 68.5% vs. 62.9%, p =0.036), more eccentric distribution (anterior versus posterior: 70.1% versus 53.8%, p =0.015) and higher rate of intraplaque hemorrhage (anterior versus posterior: 17.1% versus 7.7%, p =0.046). The plaques in posterior circulation had a thicker lesion wall (posterior versus anterior 16.58± 8.25 mm 2 vs. 9.10± 4.07 mm 2 , p <0.001) and higher enhancement index (posterior versus anterior 39.04± 8.50 vs. 23.32± 2.46, p <0.001) than the plaques in anterior circulation. Conclusions: The lesions in posterior circulations could be obscure on MRA. The area stenosis, intraplaque hemorrhage and enhancement index differed between circulations.

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Increased Wall Enhancement During Follow-Up as a Predictor of Subsequent Aneurysmal Growth

Stroke ◽

10.1161/strokeaha.119.028431 ◽

2020 ◽

Vol 51 (6) ◽

pp. 1868-1872 ◽

Cited By ~ 4

Author(s):

Florent Gariel ◽

Wagih Ben Hassen ◽

Grégoire Boulouis ◽

Romain Bourcier ◽

Denis Trystram ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Predictive Value ◽

Vessel Wall ◽

De Novo ◽

Morphological Changes ◽

Multivariable Analysis ◽

Resonance Imaging ◽

Unruptured Intracranial Aneurysms

Background and Purpose— Absence of arterial wall enhancement (AWE) of unruptured intracranial aneurysms (UIA) has shown promise at predicting which aneurysms will not rupture. We here tested the hypothesis that increased enhancement during follow-up (increased intensity, extension, or thickness or appearance of de novo enhancement), assessed using vessel wall magnetic resonance imaging, was associated with higher rates of subsequent growth. Methods— Patients with UIA were included between 2012 and 2018. Two readers independently rated AWE modification on 3T vessel wall magnetic resonance imaging, and morphological changes on time-of-flight magnetic resonance angiography during follow-up. Results— A total of 129 patients harboring 145 UIA (mean size 4.1 mm) met study criteria, of which 12 (8.3%) displayed morphological growth at 2 years. Of them, 8 demonstrated increased AWE during follow-up before or concurrently to morphological growth, and 4 had preexisting AWE that remained stable before growth. In the remaining 133 (nongrowing) UIAs, no AWE modifications were found. In multivariable analysis, increased AWE, not size, was associated with UIA growth (relative risk, 26.1 [95% CI, 7.4–91.7], P <0.001). Sensitivity, specificity, positive predictive value, and negative predictive value for UIA growth of increased AWE during follow-up were, respectively, of 67%, 100%, 96%, and 100%. Conclusions— Increased AWE during follow-up of conservatively managed UIAs predicts aneurysm growth over a 2-year period. This may impact UIA management towards closer monitoring or preventive treatment. Replication in a different setting is warranted.

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