Magnetic Resonance Imaging Techniques in the Evaluation of Stroke and Neurovascular Disease

Early intervention remains vital in the management of acute stroke. The goals of imaging techniques are to establish a diagnosis as early as possible and to obtain accurate information about the intracranial vasculature and brain perfusion to guide therapeutic decisionmaking. Magnetic resonance imaging (MRI) and contrast-enhanced magnetic resonance angiography (CE-MRA) are valuable techniques in the evaluation of acute stroke and can provide diagnostic information on the underlying pathophysiological changes. Gadolinium-based contrast agents (GBCAs) facilitate the diagnosis of ischaemic stroke by accentuating abnormal flow kinetics and the diagnosis of nonischaemic stroke by assisting in the detection and characterisation of intracranial aneurysms and arteriovenous malformations (AVMs). Contrast agents may also be employed in the characterisation of vascular atherosclerotic plaque. Gadobutrol (Gadovist®, Gadavist®) is a high relaxivity contrast agent which combines an excellent safety profile and proven high efficacy. As the only high concentration contrast media it allows to inject at a small and compact bolus, which has a direct impact on the performance of MRA or perfusion MRI procedure.

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Biocompatible dextran-coated gadolinium-doped cerium oxide nanoparticles as MRI contrast agents with high T1 relaxivity and selective cytotoxicity to cancer cells

Journal of Materials Chemistry B ◽

10.1039/d1tb01147b ◽

2021 ◽

Author(s):

Anton Popov ◽

Maxim Artemovich Abakumov ◽

Irina Savintseva ◽

Artem Ermakov ◽

Nelly Popova ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Contrast Agents ◽

Mri Contrast Agents ◽

Cerium Oxide Nanoparticles ◽

Oxide Nanoparticles ◽

Resonance Imaging ◽

Mri Contrast ◽

Selective Cytotoxicity ◽

Magnetic Resonance Imaging Mri

Gd-based complexes are widely used as magnetic resonance imaging (MRI) contrast agents. The safety of previously approved contrast agents is questionable and is being re-assessed. The main causes of concern...

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Pushing the Sensitivity Envelope of Lanthanide-Based Magnetic Resonance Imaging (MRI) Contrast Agents for Molecular Imaging Applications

Accounts of Chemical Research ◽

10.1021/ar800192p ◽

2009 ◽

Vol 42 (7) ◽

pp. 822-831 ◽

Cited By ~ 279

Author(s):

Silvio Aime ◽

Daniela Delli Castelli ◽

Simonetta Geninatti Crich ◽

Eliana Gianolio ◽

Enzo Terreno

Keyword(s):

Magnetic Resonance Imaging ◽

Molecular Imaging ◽

Magnetic Resonance ◽

Contrast Agents ◽

Mri Contrast Agents ◽

Resonance Imaging ◽

Mri Contrast ◽

Magnetic Resonance Imaging Mri

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Perfusion Magnetic Resonance Imaging to Assess Brain Tumor Responses to New Therapies

Cancer Control ◽

10.1177/107327489800500202 ◽

1998 ◽

Vol 5 (2) ◽

pp. 115-123 ◽

Cited By ~ 16

Author(s):

Michael H. Lev ◽

Fred Hochberg

Keyword(s):

Magnetic Resonance Imaging ◽

Brain Tumor ◽

Magnetic Resonance ◽

Imaging Techniques ◽

Perfusion Mri ◽

Perfusion Magnetic Resonance Imaging ◽

Normal Brain ◽

Resonance Imaging ◽

New Therapies ◽

Magnetic Resonance Imaging Mri

Background: Although magnetic resonance imaging (MRI) is effective in detecting the location of intracranial tumors, new imaging techniques have been studied that may enhance the specificity for the prediction of histologic grade of tumor and for the distinction between recurrence and tumor necrosis associated with cancer therapy. Methods: The authors review their experience and that of others on the use of perfusion magnetic resonance imaging to evaluate responses of brain tumors to new therapies. Results: Functional imaging techniques that can distinguish tumor from normal brain tissue using physiological parameters. These new approaches provide maps of tumor perfusion to monitor the effects of novel compounds that restrict tumor angiogenesis. Conclusions: Perfusion MRI not only may be as effective as radionuclide-based techniques in sensitivity and specificity in assessing brain tumor responses to new therapies, but also may offer higher resolution and convenient co-registration with conventional MRI, as well as time- and cost-effectiveness. Further study is needed to determine the role of perfusion MRI in assessing brain tumor responses to new therapies.

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Reasons for discordances between ultrasonography and magnetic resonance imaging in the evaluation of the ankle, hindfoot and heel of the patients with rheumatoid arthritis

Medical Ultrasonography ◽

10.11152/mu-2304 ◽

2019 ◽

Vol 21 (4) ◽

pp. 405 ◽

Cited By ~ 2

Author(s):

Oana Șerban ◽

Daniela Fodor ◽

Iulia Papp ◽

Mihaela Cosmina Micu ◽

Dan Gabriel Duma ◽

...

Keyword(s):

Rheumatoid Arthritis ◽

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Disease Activity ◽

Activity Index ◽

Imaging Techniques ◽

Disease Activity Index ◽

Resonance Imaging ◽

Magnetic Resonance Imaging Mri ◽

Definition Of

Aim: To compare the ultrasonography (US) performance with magnetic resonance imaging (MRI) in identifying pathology in ankles, hindfeet and heels of rheumatoid arthritis (RA) patients and to evaluate the reasons for discordances between the two imaging methods.Material and methods: RA patients were enrolled and evaluated using the Clinical Disease Activity Index (CDAI) and the Disease Activity Score 28 with C-reactive Protein (DAS28-CRP). The ankle (tibiotalar joint, tendons), hindfoot (talonavicular, subtalar joints) and heel of the most symptomatic or dominant foot (for the asymptomatic patient)were evaluated by two pairs of examiners using US and contrast-enhanced MRI.Results: Totally, 105 joints, 245 tendons and 35 heels in 35 patients [mean age 59.2±11.25 years old, median disease duration 36 (16.5-114), mean CDAI 19.87±12.7] were evaluated. The interobserver agreements between the two sonographers, and the two radiologists were good and very good (k=0.624-0.940). The overall agreement between US and MRI was very good for subcalcaneal panniculitis (k=0.928, p<0.001), moderate for synovitis (k=0.463, p<0.001) and tenosynovitis (k=0.514, p<0.001), fair for osteophytes (k=0.260, p=0.004), and poor for erosions (k=0.063, p=0.308) and heel’s structures. MRI found more erosions, synovitis, osteophytes,tenosynovitis and retrocalcaneal bursitis, but US found more enthesophytes and plantar fasciitis. Many of the discordancesbetween the two imaging techniques have explanations related to the technique itself or definition of the pathologic findings.Conclusions: US is comparable to MRI for the evaluation of ankle, hindfoot and heel in RA patients and discordances in theinterpretation of the pathological findings/normal structures must be carefully analyzed.

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Effect of Gd and Dy Concentrations in Layered Double Hydroxides on Contrast in Magnetic Resonance Imaging

Processes ◽

10.3390/pr8040462 ◽

2020 ◽

Vol 8 (4) ◽

pp. 462 ◽

Cited By ~ 1

Author(s):

Karina Nava Andrade ◽

Gregorio Guadalupe Carbajal Arízaga ◽

José Antonio Rivera Mayorga

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Contrast Agents ◽

Mri Contrast Agents ◽

Resonance Imaging ◽

Mri Contrast ◽

Molar Ratios ◽

Magnetic Resonance Imaging Mri ◽

Double Hydroxide ◽

Double Hydroxides

In this work, we explore the synthesis of layered double hydroxide (LDH) particles containing different molar ratios of Gd3+ and Dy3+ cations. A single crystalline phase was obtained for Zn2.0Al0.75Gd0.125Dy0.125-LDH and Zn2.0Al0.5Gd0.25Dy0.25-LDH, and their efficiency as contrast agents was evaluated by T1- and T2-weighted magnetic resonance imaging (MRI). Both GdDy-LDHs exhibited longitudinal relaxivity (r1) higher than a commercial reference. The highest contrast in the T1 mode was achieved with the Zn2.0Al0.75Gd0.125Dy0.125-LDH, which contained the lowest concentration of lanthanides; this efficiency is related to the lowest amount of carbonate anions complexing the lanthanide sites. On the contrary, the best contrast in the T2 mode was achieved with Zn2.0Al0.5Gd0.25Dy0.25-LDH. Zn2.0Al0.75Gd0.125Dy0.125-LDH and Zn2.0Al0.5Gd0.25Dy0.25-LDH presented r2/r1 ratios of 7.9 and 22.5, respectively, indicating that the inclusion of gadolinium and dysprosium into layered structures is a promising approach to the development of efficient bimodal (T1/T2) MRI contrast agents.

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Magnetic resonance imaging of salivary glands

Clinical and Laboratorial Research in Dentistry ◽

10.11606/issn.2357-8041.clrd.2019.152344 ◽

2019 ◽

Author(s):

Danielle Ayumi Nishimura ◽

Ana Luiza Esteves Carneiro ◽

Kaisermann Costa ◽

Wladimir Gushiken de Campos ◽

Jefferson Xavier de Oliveira ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Salivary Glands ◽

Imaging Techniques ◽

Neck Region ◽

Evaluation Instrument ◽

Resonance Imaging ◽

Tissue Contrast ◽

Excellent Method ◽

Magnetic Resonance Imaging Mri

Salivary glands tumors account for 2-5% of tumors in the head and neck region, possibly being benign or malignant. Magnetic resonance imaging (MRI) presents high soft tissue contrast resolution, thus being an excellent method for salivary gland analysis. The objective of this literature review is to analyze MRI as an evaluation instrument for the diagnosis of salivary glands lesions. Compared to other imaging techniques, MRI can better evaluate the relationship between adjacent anatomical structures, presenting greater sensitivity and specificity.

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Ferritin: A Platform for MRI Contrast Agents Delivery

Inorganics ◽

10.3390/inorganics7030033 ◽

2019 ◽

Vol 7 (3) ◽

pp. 33 ◽

Cited By ~ 3

Author(s):

Maria Ruggiero ◽

Diego Alberti ◽

Valeria Bitonto ◽

Simonetta Geninatti Crich

Keyword(s):

Magnetic Resonance Imaging ◽

Targeted Therapy ◽

Magnetic Resonance ◽

Contrast Agents ◽

Mri Contrast Agents ◽

Resonance Imaging ◽

Mri Contrast ◽

Magnetic Resonance Imaging Mri ◽

Accurate Imaging ◽

Unique Surface

The search for high relaxivities and increased specificity continues to be central to the development of paramagnetic contrast agents for magnetic resonance imaging (MRI). Ferritin, due to its unique surface properties, architecture, and biocompatibility, has emerged as a natural nanocage that can potentially help to reach both these goals. This review aims to highlight recent advances in the use of ferritin as a nanoplatform for the delivery of metal-based MRI contrast agents (containing Gd3+, Mn2+, or Fe2O3) alone or in combination with active molecules used for therapeutic purposes. The collected results unequivocally show that the use of ferritin for contrast agent delivery leads to more accurate imaging of cancer cells and a significantly improved targeted therapy.

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Uniform Fe3O4/Gd2O3-DHCA nanocubes for dual-mode magnetic resonance imaging

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.11.84 ◽

2020 ◽

Vol 11 ◽

pp. 1000-1009

Author(s):

Miao Qin ◽

Yueyou Peng ◽

Mengjie Xu ◽

Hui Yan ◽

Yizhu Cheng ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Contrast Agents ◽

Mri Contrast Agents ◽

Clinical Diagnostics ◽

Resonance Imaging ◽

Dual Mode ◽

Mri Contrast ◽

Magnetic Resonance Imaging Mri

The multimodal magnetic resonance imaging (MRI) technique has been extensively studied over the past few years since it offers complementary information that can increase diagnostic accuracy. Simple methods to synthesize contrast agents are necessary for the development of multimodal MRI. Herein, uniformly distributed Fe3O4/Gd2O3 nanocubes for T 1–T 2 dual-mode MRI contrast agents were successfully designed and synthesized. In order to increase hydrophilicity and biocompatibility, the nanocubes were coated with nontoxic 3,4-dihydroxyhydrocinnamic acid (DHCA). The results show that iron (Fe) and gadolinium (Gd) were homogeneously distributed throughout the Fe3O4/Gd2O3-DHCA (FGDA) nanocubes. Relaxation time analysis was performed on the images obtained from the 3.0 T scanner. The results demonstrated that r 1 and r 2 maximum values were 67.57 ± 6.2 and 24.2 ± 1.46 mM−1·s−1, respectively. In vivo T 1- and T 2-weighted images showed that FGDA nanocubes act as a dual-mode contrast agent enhancing MRI quality. Overall, these experimental results suggest that the FGDA nanocubes are interesting tools that can be used to increase MRI quality, enabling accurate clinical diagnostics.

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