Magnetic resonance imaging dynamics of contrast medium uptake in vestibular schwannomas

2011 ◽  
Vol 114 (2) ◽  
pp. 394-399
Author(s):  
Stefan Rampp ◽  
Christian Scheller ◽  
Julian Prell ◽  
Tobias Engelhorn ◽  
Christian Strauss ◽  
...  
Keyword(s):  
Mr Imaging ◽  
Contrast Agent ◽  
Contrast Medium ◽  
Contrast Enhancement ◽  
Image Acquisition ◽  
Resonance Imaging ◽  
Standardized Protocol ◽  
Maximum Change ◽  
Contrast Agent Administration ◽  
Over Time

Object Efficacy of radiosurgery in vestibular schwannoma (VS) is usually documented by changes of tumor size and by loss of contrast enhancement in MR imaging within the central portion of the lesion. Until now, however, correlation between contrast enhancement and timing of image acquisition in nontreated VS has not been analyzed systematically. The authors undertook this study to investigate changes in contrast enhancement with respect to latency of image acquisition after contrast agent administration. Methods The dynamics of contrast medium uptake were evaluated with T1-weighted VIBE MR imaging sequences performed immediately and 1.5, 3.5, 4.5, 9.5, and 11.5 minutes after administration of single dose of Gd in 21 patients with nontreated medium- to large-sized VSs. Signal-to-noise (SNR) and contrast-to-noise ratio (CNR) of tumors were evaluated, and volumes of central nonenhancing areas (NEAs) were determined. Results The interior appearance of the tumors changed considerably over time. The NEA significantly diminished in size (p < 0.0001, Friedman test) and almost completely disappeared in all but 2 patients. Compared to images at 1.5 minutes, NEA volumes decreased to a median of 36% at 3.5 minutes and 34% at 4.5 minutes, showing smaller changes after that—9% at 9.5 minutes and 3% at 11.5 minutes. Tumor SNR and CNR increased over time. The maximum change in the median values for SNR and CNR were a 72% increase and 117% increase, respectively; both occurred at 1.5 minutes after Gd administration. Conclusions Contrast enhancement in VS MR imaging varies according to the duration of the delay between contrast agent administration and image acquisition. Postradiotherapy changes in contrast enhancement of VS can therefore not be attributed only to effective radiotherapy. So-called “loss of central contrast enhancement” may be falsely detected because of timing. A standardized protocol with defined timing of image acquisition may increase comparability of contrast uptake in VS.

Delineating Toxicity Mechanisms Associated with MRI Contrast Enhancement through a Multidimensional Toxicogenomic Profiling of Gadolinium

2022 ◽  
Author(s):  
Roger M. Pallares ◽  
Dahlia D An ◽  
Solene Hebert ◽  
David Faulkner ◽  
Alex Loguinov ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Contrast Agent ◽  
Contrast Enhancement ◽  
Clinical Settings ◽  
Resonance Imaging ◽  
Mri Contrast ◽  
Toxicity Mechanisms

Although gadolinium is widely used for magnetic resonance imaging in clinical settings, many concerns regarding its toxicity and bioaccumulation after gadolinium-based contrast agent (GBCA) administration have been raised and published...

Colorectal Liver Metastases: Contrast Agent Diffusion Coefficient for Quantification of Contrast Enhancement Heterogeneity at MR Imaging

Radiology ◽  
2008 ◽  
Vol 248 (3) ◽  
pp. 901-909 ◽  
Author(s):  
Guang Jia ◽  
Craig O'Dell ◽  
Johannes T. Heverhagen ◽  
Xiangyu Yang ◽  
Jiachao Liang ◽  
...  
Keyword(s):  
Diffusion Coefficient ◽  
Mr Imaging ◽  
Contrast Agent ◽  
Liver Metastases ◽  
Contrast Enhancement ◽  
Colorectal Liver Metastases

scholarly journals SPIO-Loaded Nanostructured Lipid Carriers for T2-weighted Magnetic Resonance Imaging of Hepatocarcinoma

2020 ◽  
Author(s):  
Chen-ying Lu ◽  
Nan-Nan Zhang ◽  
Gao-feng Shu ◽  
Xiu-liang Zhu ◽  
Min-jiang Chen ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Hepatocellular Carcinoma ◽  
Magnetic Resonance ◽  
Mr Imaging ◽  
Contrast Agent ◽  
Diffusion Method ◽  
Nanostructured Lipid Carrier ◽  
Resonance Imaging ◽  
Mri Contrast

Abstract Background The development of sensitive and specific MRI contrast agents for early diagnosis of hepatocellular carcinoma is highly demanded. Here, a peptide A54 (sequence: AGKGTPSLETTP) functionalized superparamagnetic iron oxide nanoparticles (SPIONs)-based magnetic nanostructured lipid carrier(A54-MNLC)as a hepatoma targeting negative magnetic resonance imaging (MRI) contrast agent was developed. Results Firstly, the A54 peptide functionalized PEGylated SA (A54-PEG-SA) was synthesized by the coupling reaction between A54 and NH2-PEG-SA. Then SPIONs-loaded MNLC(MNLC and A54-MNLC)were prepared by the solvent diffusion method. The A54-MNLC with a diameter of about 50 nm, and in vitro cell viability study revealed that the prepared A54-MNLC was cytocompatible in the given particles’ concentration ranges. The cellular uptake results indicated that A54-MNLC was able to be uptaken specifically by human hepatoma cell line (Bel-7402 cells) and also can be used as efficient probe for targeted MR imaging of cancer cells in vitro. The in vivo MR imaging experiments using an orthotopic implantation model further validated the hepatoma-targeting ability of A54-MNLC with a more remarkable MR imaging contrast effect compared to MNLC. Conclusions These results demonstrate that the A54-MNLC is a promising nanoplatform as a targeted MR imaging contrast agent for the diagnosis of hepatocellular carcinoma.

scholarly journals Fluorinated EuII-based multimodal contrast agent for temperature- and redox-responsive magnetic resonance imaging

2017 ◽  
Vol 8 (12) ◽  
pp. 8345-8350 ◽  
Author(s):  
Lina A. Basal ◽  
Matthew D. Bailey ◽  
Jonathan Romero ◽  
Meser M. Ali ◽  
Lyazat Kurenbekova ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Contrast Agent ◽  
Contrast Enhancement ◽  
Resonance Imaging ◽  
Temperature Dependent ◽  
Redox Responsive

Mechanistically unique 19F-EuII/III complex reports redox in vivo using both 1H- and 19F-MRI and displays temperature-dependent contrast enhancement.

Evaluation of intraaxial enhancing brain tumors on magnetic resonance imaging: intraindividual crossover comparison of gadobenate dimeglumine and gadopentetate dimeglumine for visualization and assessment, and implications for surgical intervention

2007 ◽  
Vol 106 (4) ◽  
pp. 557-566 ◽  
Author(s):  
Matthew J. Kuhn ◽  
Piero Picozzi ◽  
Joseph A. Maldjian ◽  
Ilona M. Schmalfuss ◽  
Kenneth R. Maravilla ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Brain Tumors ◽  
Mr Imaging ◽  
Contrast Agent ◽  
Contrast Enhancement ◽  
Spin Echo ◽  
Gadopentetate Dimeglumine ◽  
Gadobenate Dimeglumine ◽  
Kappa Statistics ◽  
End Points

Object The goal in this article was to compare 0.1 mmol/kg doses of gadobenate dimeglumine (Gd-BOPTA) and gadopentetate dimeglumine, also known as gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA), for enhanced magnetic resonance (MR) imaging of intraaxial brain tumors. Methods Eighty-four patients with either intraaxial glioma (47 patients) or metastasis (37 patients) underwent two MR imaging examinations at 1.5 tesla, one with Gd-BOPTA as the contrast agent and the other with Gd-DTPA. The interval between fully randomized contrast medium administrations was 2 to 7 days. The T1-weighted spin echo and T2-weighted fast spin echo images were acquired before administration of contrast agents and T1-weighted spin echo images were obtained after the agents were administered. Acquisition parameters and postinjection acquisition times were identical for the two examinations in each patient. Three experienced readers working in a fully blinded fashion independently evaluated all images for degree and quality of available information (lesion contrast enhancement, lesion border delineation, definition of disease extent, visualization of the lesion's internal structures, global diagnostic preference) and quantitative enhancement (that is, the extent of lesion enhancement after contrast agent administration compared with that seen before its administration [hereafter referred to as percent enhancement], lesion/brain ratio, and contrast/noise ratio). Differences were tested with the Wilcoxon signed-rank test. Reader agreement was assessed using kappa statistics. Significantly better diagnostic information/imaging performance (p < 0.0001, all readers) was obtained with Gd-BOPTA for all visualization end points. Global preference for images obtained with Gd-BOPTA was expressed for 42 (50%), 52 (61.9%), and 56 (66.7%) of 84 patients (readers 1, 2, and 3, respectively) compared with images obtained with Gd-DTPA contrast in four (4.8%), six (7.1%), and three (3.6%) of 84 patients. Similar differences were noted for all other visualization end points. Significantly greater quantitative contrast enhancement (p < 0.04) was noted after administration of Gd-BOPTA. Reader agreement was good (κ > 0.4). Conclusions Lesion visualization, delineation, definition, and contrast enhancement are significantly better after administration of 0.1 mmol/kg Gd-BOPTA, potentially allowing better surgical planning and follow up and improved disease management.

Terbium-doped gadolinium oxide nanoparticles prepared by laser ablation in liquid for use as a fluorescence and magnetic resonance imaging dual-modal contrast agent

2015 ◽  
Vol 17 (2) ◽  
pp. 1189-1196 ◽  
Author(s):  
Fei Chen ◽  
Min Chen ◽  
Chuan Yang ◽  
Jun Liu ◽  
Ningqi Luo ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Laser Ablation ◽  
Magnetic Resonance ◽  
Mr Imaging ◽  
Contrast Agent ◽  
Fluorescence Imaging ◽  
Oxide Nanoparticles ◽  
Resonance Imaging ◽  
Laser Ablation In Liquid ◽  
Promising Candidate

Gd2O3:Tb is a promising candidate for use as a dual-modal contrast agent combining fluorescence imaging with MR imaging.

Intratendinous Alterations as Imaged by Ultrasound and Contrast Medium-Enhanced Magnetic Resonance in Chronic Achillodynia

1998 ◽  
Vol 19 (5) ◽  
pp. 311-317 ◽  
Author(s):  
Tomas Movin ◽  
Maria Kristoffersen-Wiberg ◽  
Adel Shalabi ◽  
Adel Gad ◽  
Peter Aspelin ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Achilles Tendon ◽  
Contrast Medium ◽  
Structural Basis ◽  
Resonance Imaging ◽  
Echo Signal ◽  
Standardized Protocol ◽  
Contrast Enhanced ◽  
Per Se ◽  
Tendon Pathology

Objectives: We performed a comparative study of ultrasonography and gadolinium imaging contrast-enhanced T1-weighted magnetic resonance to evaluate tendon pathology in chronic Achilles tendon disorder. Another main issue was to evaluate the structural basis as defined by histopathology from hypoechoic compared with normoechic areas within the same tendon. Materials and Methods: Twenty patients (16 male, 4 females, median age 40 years) with chronic achillodynia participated in the study. Clinical examination revealed swelling and tenderness localized to the midportion of the Achilles tendon. Contrast medium-enhanced magnetic resonance imaging (CME-MRI) was performed in all patients. Ultrasonography-guided core biopsies were taken from regions with a clear widening of the tendon and a pathologic low-echo signal as well as from normoechoic areas. The specimens were analyzed with a standardized protocol giving a total tendon score (0–24), and a stereologic method for quantification of glycosaminoglycan (GAG)-rich areas. Results: The volume of the intratendinous abnormality was larger in 13 of 20 when imaged by CME-MR ( P < 0.05), whereas the shape and enlargement of the tendon per se were similarly imaged by ultrasound (US) and CME-MR. Tendon pathology as imaged by US was graded as severe from hypoechoic regions and moderate from normoechoic regions. The corresponding quantification of GAGs was 0.36 compared with 0.17, respectively ( P < 0.001). Conclusion: CME-MR imaging revealed greater sensitivity in demonstrating intratendinous pathology than the ultrasound; this was documented by the larger size of the corresponding lesion and the fact that the pathology was occurring in areas that were considered normal by ultrasonography. US hypoechoic areas showed a markedly abnormal tendon structure including an increased amount of GAG-rich areas. However, moderate pathology was also found in the neighboring normoechogenous areas within the same tendon, indicating a more generalized disorder than depicted by echogenic properties.

Sign in / Sign up

Export Citation Format

Share Document