scholarly journals Spin-echo MRI underestimates functional changes in microvascular cerebral blood plasma volume using exogenous contrast agent

2007 ◽  
Vol 58 (4) ◽  
pp. 769-776 ◽  
Author(s):  
Joseph B. Mandeville ◽  
Francisca P. Leite ◽  
John J.A. Marota
Keyword(s):  
Contrast Agent ◽  
Blood Plasma ◽  
Plasma Volume ◽  
Spin Echo ◽  
Functional Changes ◽  
Exogenous Contrast Agent

scholarly journals Measurement of arteriolar blood volume in brain tumors using MRI without exogenous contrast agent administration at 7T

2016 ◽  
Vol 44 (5) ◽  
pp. 1244-1255 ◽  
Author(s):  
Yuankui Wu ◽  
Shruti Agarwal ◽  
Craig K. Jones ◽  
Andrew G. Webb ◽  
Peter C.M. van Zijl ◽  
...  
Keyword(s):  
Brain Tumors ◽  
Contrast Agent ◽  
Blood Volume ◽  
Contrast Agent Administration ◽  
Exogenous Contrast Agent

The switch from Gd-DTPA to Gd-DOTA is not associated with decrease of the T1 signal intensity of the pallidus and dentate in a pediatric population

2020 ◽  
pp. 028418512092792
Author(s):  
Pietro Gulino ◽  
Andrea Bianchi ◽  
Stefano Diciotti ◽  
Alessandra Scionti ◽  
Lapo Sali ◽  
...  
Keyword(s):  
Contrast Agent ◽  
Gray Matter ◽  
Signal Intensity ◽  
Pediatric Patients ◽  
Spin Echo ◽  
Pediatric Population ◽  
Rate Of Change ◽  
Middle Cerebellar Peduncle ◽  
Gadoterate Meglumine ◽  
Cerebellar Peduncle

Background The switch from the linear gadolinium-based contrast agent (GBCA) gadopentate dimeglumine (Gd_DTPA) to the macrocyclic GBCA gadobutrol is associated with a decrease of the T1 signal intensity (SI) in brain gray matter nuclei. The effects of the switch to other macrocyclic GBCAs are not yet established. Purpose To explore the effects of switching from Gd-DTPA to the macrocyclic GBCA gadoterate meglumine (Gd-DOTA) in pediatric patients. Material and Methods We measured the pallidus/middle cerebellar peduncle (MCP) SI ratio and the dentate/MCP SI ratio in pre-contrast sagittal T1-weighted spin-echo images in nine patients who had received ≥6 administrations of Gd-DTPA and then of Gd-DOTA, in 18 patients who had received ≥6 administrations of Gd-DOTA alone, and in nine age-matched controls without prior GBCA administrations. Serial assessment was performed in patients who switched from Gd-DTPA to Gd-DOTA. Finally, the rate of change of pallidal/MCP and dentate/MCP SI ratios between the first and last Gd-DOTA administrations was compared. Results The pallidal/MCP and dentate/MCP SI ratios were ( P < 0.05) higher in patients with prior Gd-DTPA and Gd-DOTA administrations compared to the controls. After the switch, the pallidal/MCP SI ratio increased in nine patients and the dentate/MCP ratio in seven patients. The rate of change of pallidal/MCP SI ratio after Gd-DOTA was higher ( P < 0.01) in patients who had previously received Gd-DTPA (mean 2.89 ± 2.6%) than in patients who had received Gd-DOTA alone (mean 0.53 ± 0.89%). Conclusion T1 SI in gray matter nuclei does not decrease after switching from Gd-DTPA to Gd-DOTA. The switch effects from Gd-DTPA to each macrocyclic GBCA should be individually evaluated.

scholarly journals EXPERIMENTAL EVALUATION OF MN(II)-TRANS-1,2-DIAMINOCYCLEHEXANE-N,N,N',N'TETRAACETATE AS PARAMAGNETIC CONTRAST AGENT FOR ENHANCEMENT OF CEREBRAL MENINGEOMAS IN DOGS

2014 ◽  
Vol 13 (3) ◽  
pp. 63-69
Author(s):  
V. Yu. Ussov ◽  
A. I. Bezlepkin ◽  
O. Yu. Borodin ◽  
M. L. Belyanin ◽  
V. D. Filimonov
Keyword(s):  
Contrast Agent ◽  
Tumor Tissue ◽  
Spin Echo ◽  
Trade Mark ◽  
Resonance Imaging ◽  
Cerebral Tumor ◽  
Paramagnetic Contrast Agent ◽  
Clinical Magnetic Resonance Imaging ◽  
Contrast Enhanced ◽  
Cerebral Mri

Aim of research. We have evaluated the abilities of new original paramagnetic contrast agent Mn-DCTA (0,5 mol solution of Manganese(II) complex with trans-1,2-diaminocyclohexane-N,N,N',N'-tetraacetate, registered trade mark Cyclomang) for contrast-enhanced imaging of brain meningeomas in dogs.Material and methods. Twelve animals were included, all with brain tumors reveald during out-patient veterinary examinations. In ten of twelve the diagnosis was verified later by pathomorphologic study. The cerebral MRI has been carred out as set of axial, sagittal and coronal slices as thin as three to five mm, covering all the volume of brain.The scanning parameters in T1-weighted spin-ech mode were as follows: TR = 400–500 ms, TE = 15–20 ms, the dose of injected paramagnetic was standardised as 1 mmol per 10 kg of body weight. For quantitative analysis the index of enhancement was calculated.Results. In all cases the sure enhancement with clear visualization of cerebral tumor was obtained due to highly intensive uptake of Mn-DCTA to the tumor tissue. When evaluated quantitatively the uptake of Mn-DCTA to the tumor gave the index of enhancement in T1-weighted spin-echo mode as high as IE = 1,72 ± 0,18 for the central parts of tumor and IE = 2,08 ± 0,23 for the peripheral ones, where as in control animals it was far below these values. Intravenous injection of Mn-DCTA to dogs with cerebral tumors did not induce any detectable pathologic or even physiologic effects.Conclusion. Henceforth we conclude the Mn-DCTA provides highly available methodologically simple imaging of cerebral meningeomas and can be thought out as promising paramagnetic agent for clinical magnetic resonance imaging in humans.

scholarly journals Magnetic resonance imaging can diagnostic early morphofunctional changes in the myocardium in young people with type 1 diabetes

2019 ◽  
Vol 10 (1) ◽  
pp. 29-35
Author(s):  
Kirill A. Popov ◽  
Irina Z. Bondarenko ◽  
Elena V. Biryukova ◽  
Elena V. Averkieva ◽  
Alexander V. Vorontsov
Keyword(s):  
Magnetic Resonance Imaging ◽  
Type 1 Diabetes ◽  
Magnetic Resonance ◽  
Young People ◽  
Left Ventricle ◽  
Contrast Agent ◽  
Young Patients ◽  
Resonance Imaging ◽  
Functional Changes

Aim. To study the morphofunctional state of the myocardium in young people with diabetes mellitus 1 using magnetic resonance imaging (MRI) technology. Materials and methods. 38 patients (14 men, 24 women), aged 18 to 36 years old, with an experience of type 1 diabetes from 5 to 16 years old were underwent contrastive MRI of the heart. The exclusion criteria were: pronounced electrolyte disorders in the blood, dysproteinemia, chronic liver and kidney failure - glomerular filtration rate (EPI)≤60 ml/min/1.73 m2, thyroid dysfunction, obesity (body mass index ≥30 kg/m2), diagnosed cardiovascular diseases, contraindications for MRI. The indicators of functional changes in the left ventricle (circular strain, strain relaxation index - SRI), peak early diastolic strain (PSRDS) were obtained and the accumulation of the contrast agent in the delayed period were assessed. Results. The obtained results of strain, SRI, PSRDS do not allow to exclude the presence of functional changes in the myocardium of the left ventricle. In 42.11%, zones of accumulation of the contrast agent were visualized in the delayed period (insignificant - 28.95% and moderate accumulation - 13.16%), mainly by the endocardium of the cardiac apparatus (mitral and tricuspid), and in one observation (2.9%) - in combination with unexpressed diffuse heterogeneity of the myocardium of the left ventricle. Conclusion. MRI of the heart is a promising direction in the assessment of early morphofunctional changes in the structure of the myocardium, which will probably make it possible to predict life-threatening changes in the heart muscle in young patients with type 1 diabetes.

scholarly journals Descriptive analysis of MRI functional changes occurring during reduced dose radiotherapy for myxoid liposarcomas

2021 ◽  
Vol 94 (1126) ◽  
pp. 20210310
Author(s):  
Evanthia Kousi ◽  
Christina Messiou ◽  
Aisha Miah ◽  
Matthew Orton ◽  
Rick Haas ◽  
...  
Keyword(s):  
Contrast Agent ◽  
Descriptive Analysis ◽  
Early Response ◽  
Tumour Volume ◽  
Response To Treatment ◽  
Transfer Constant ◽  
Functional Changes ◽  
Reduced Dose ◽  
Pre Treatment ◽  
Myxoid Liposarcomas

Objectives: Myxoid liposarcomas (MLS) show enhanced response to radiotherapy due to their distinctive vascular pattern and therefore could be effectively treated with lower radiation doses. This is a descriptive study to explore the use of functional MRI to identify response in a uniform cohort of MLS patients treated with reduced dose radiotherapy Methods: 10 patients with MLS were imaged pre-, during, and post-radiotherapy receiving reduced dose radiotherapy and the response to treatment was histopathologically assessed post-radiotherapy. Apparent diffusion coefficient (ADC), T2* relaxation time, volume transfer constant (Ktrans), initial area under the gadolinium curve over 60 s (IAUGC60) and (Gd) were estimated for a central tumour volume. Results: All parameters showed large inter- and intrasubject variabilities. Pre-treatment (Gd), IAUGC60 and Ktrans were significantly different between responders and non-responders. Post-radiotherapy reductions from baseline were demonstrated for T2*, (Gd), IAUGC60 and Ktrans for responders. No statistically significant ADC differences were demonstrated between the two response groups. Significantly greater early tumour volume reductions were observed for responders. Conclusions: MLS are heterogenous lesions, characterised by a slow gradual contrast-agent uptake. Pre-treatment vascular parameters, early changes to tumour volume, vascular parameters and T2* have potential in identifying response to treatment. The delayed (Gd) is a suitable descriptive parameter, relying simply on T1 measurements. Volume changes precede changes in MLS functionality and could be used to identify early response. Advances in knowledge: MLS are are characterised by slow gradual contrast-agent uptake. Measurement of the delayed contrast-agent uptake (Gd) is simple to implement and able to discriminate response.

Relaxivity Optimization of a PEGylated Iron-Oxide-Based Negative Magnetic Resonance Contrast Agent for T2-Weighted Spin–Echo Imaging

ACS Nano ◽  
2012 ◽  
Vol 6 (2) ◽  
pp. 1619-1624 ◽  
Author(s):  
Elmar Pöselt ◽  
Hauke Kloust ◽  
Ulrich Tromsdorf ◽  
Marcus Janschel ◽  
Christoph Hahn ◽  
...  
Keyword(s):  
Iron Oxide ◽  
Magnetic Resonance ◽  
Contrast Agent ◽  
Spin Echo ◽  
Magnetic Resonance Contrast Agent ◽  
Magnetic Resonance Contrast ◽  
Resonance Contrast

scholarly journals Exogenous contrast agent improves sensitivity of gradient-echo functional magnetic resonance imaging at 9.4 T

2004 ◽  
Vol 52 (6) ◽  
pp. 1272-1281 ◽  
Author(s):  
Joseph B. Mandeville ◽  
Bruce G. Jenkins ◽  
Yin-Ching I. Chen ◽  
Ji-Kyung Choi ◽  
Young R. Kim ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Functional Magnetic Resonance Imaging ◽  
Contrast Agent ◽  
Functional Magnetic Resonance ◽  
Resonance Imaging ◽  
Gradient Echo ◽  
Exogenous Contrast Agent
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