keyword
MENU ▼
Read by QxMD icon Read
search

MRI contrast agent

keyword
https://www.readbyqxmd.com/read/29138455/a-scale-to-measure-mri-contrast-agent-sensitivity
#1
Rohan D A Alvares, Daniel A Szulc, Hai-Ling M Cheng
Magnetic resonance imaging (MRI) provides superior resolution of anatomical features and the best soft tissue contrast, and is one of the predominant imaging modalities. With this technique, contrast agents are often used to aid discrimination by enhancing specific features. Over the years, a rich diversity of such agents has evolved and with that, so has a need to systematically sort contrast agents based on their efficiency, which directly determines sensitivity. Herein, we present a scale to rank MRI contrast agents...
November 14, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29137496/preoperative-quantitative-dynamic-contrast-enhanced-mri-and-diffusion-weighted-imaging-predict-aggressive-disease-in-endometrial-cancer
#2
Kristine E Fasmer, Atle Bjørnerud, Sigmund Ytre-Hauge, Renate Grüner, Ingvild L Tangen, Henrica Mj Werner, Line Bjørge, Øyvind O Salvesen, Jone Trovik, Camilla Krakstad, Ingfrid S Haldorsen
Background Quantitative dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and diffusion-weighted imaging (DWI) may yield preoperative tumor biomarkers relevant for prognosis and therapy in cancer. Purpose To explore the value of preoperative DCE-MRI and DWI for the prediction of aggressive disease in endometrial cancer patients. Material and Methods Preoperative MRI (1.5-T) from 177 patients were analyzed and imaging parameters reflecting tumor microvasculature (from DCE-MRI) and tumor microstructure (from DWI) were estimated...
January 1, 2017: Acta Radiologica
https://www.readbyqxmd.com/read/29134771/detection-of-%C3%AE-amyloid-by-sialic-acid-coated-bovine-serum-albumin-magnetic-nanoparticles-in-a-mouse-model-of-alzheimer-s-disease
#3
Seyedmehdi Hossaini Nasr, Hovig Kouyoumdjian, Christiane Mallett, Sherif Ramadan, David C Zhu, Erik M Shapiro, Xuefei Huang
The accumulation and formation of β-amyloid (Aβ) plaques in the brain are distinctive pathological hallmarks of Alzheimer's disease (AD). Designing nanoparticle (NP) contrast agents capable of binding with Aβ highly selectively can potentially facilitate early detection of AD. However, a significant obstacle is the blood brain barrier (BBB), which can preclude the entrance of NPs into the brain for Aβ binding. In this work, bovine serum albumin (BSA) coated NPs are decorated with sialic acid (NP-BSAx -Sia) to overcome the challenges in Aβ imaging in vivo...
November 14, 2017: Small
https://www.readbyqxmd.com/read/29134673/modified-dixon-based-renal-dynamic-contrast-enhanced-mri-facilitates-automated-registration-and-perfusion-analysis
#4
Anneloes de Boer, Tim Leiner, Eva E Vink, Peter J Blankestijn, Cornelis A T van den Berg
PURPOSE: Renal dynamic contrast-enhanced (DCE) MRI provides information on renal perfusion and filtration. However, clinical implementation is hampered by challenges in postprocessing as a result of misalignment of the kidneys due to respiration. We propose to perform automated image registration using the fat-only images derived from a modified Dixon reconstruction of a dual-echo acquisition because these provide consistent contrast over the dynamic series. METHODS: DCE data of 10 hypertensive patients was used...
November 13, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/29134355/extracellular-contrast-agent-enhanced-mri-15-min-delayed-phase-may-improve-the-diagnostic-performance-for-hepatocellular-carcinoma-in-patients-with-chronic-liver-disease
#5
Si Eun Lee, Chansik An, Shin Hye Hwang, Jin-Young Choi, Kyunghwa Han, Myeong-Jin Kim
OBJECTIVES: To determine the value of a 15-min delayed phase in extracellular contrast agent (ECA)-enhanced magnetic resonance imaging (MRI) for evaluation of hepatocellular carcinoma (HCC) in patients with chronic liver disease. METHODS: Between 2014 and 2015, 103 patients with chronic liver disease underwent ECA-enhanced MRI; 133 lesions consisting of 107 HCCs, 23 benign lesions and three non-HCC malignancies were identified with pathological or clinical diagnosis...
November 13, 2017: European Radiology
https://www.readbyqxmd.com/read/29128994/radiologists-preferences-regarding-content-of-prostate-mri-reports-a-survey-of-the-society-of-abdominal-radiology
#6
Benjamin Spilseth, Daniel J Margolis, Sangeet Ghai, Nayana U Patel, Andrew B Rosenkrantz
PURPOSE: To evaluate radiologist preferences regarding specific content that warrants inclusion in prostate MRI reports. METHODS: Sixty-one members of the Society of Abdominal Radiology responded to a 74-item survey regarding specific content warranted in prostate MRI reports, conducted in August 2016. RESULTS: General items deemed essential report content by ≥ 50% of respondents were prostate volume (80%), extent of prostate hemorrhage (74%), TURP defects (69%), coil type (64%), BPH (61%), contrast dose (61%), contrast agent (59%), medications administered (59%), and magnet strength (54%)...
November 11, 2017: Abdominal Radiology
https://www.readbyqxmd.com/read/29125161/dimer-formation-of-gddo3a-arylsulfonamide-complexes-causes-loss-of-ph-dependency-of-relaxivity
#7
Anja Wacker, Fabio Carniato, Carlos Platas-Iglesias, David Esteban-Gomez, Hans-Jürgen Wester, Lorenzo Tei, Johannes Notni
Gadolinium(iii) complexes with pH-dependent relaxivities have been proposed as responsive magnetic resonance imaging (MRI) contrast agents (CA) for mapping of pH value in living subjects. The latter is clinically relevant because hypoxia-induced reduction of interstitial pH (acidosis) is a hallmark of tumor progression and resistance against chemotherapy. In order to obtain versatile building blocks for integration of a pH-responsive MRI-CA functionality into larger molecular assemblies, such as bioconjugates, micelles or nanoparticles, we equipped the structural motif GdDO3A-ethylene(arylsulfonic acid) with additional carboxylic acid moieties in the aromatic para-position...
November 10, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
https://www.readbyqxmd.com/read/29124781/vascular-input-function-correction-of-inflow-enhancement-for-improved-pharmacokinetic-modeling-of-liver-dce-mri
#8
Jia Ning, Tilman Schubert, Kevin M Johnson, Alejandro Roldán-Alzate, Huijun Chen, Chun Yuan, Scott B Reeder
PURPOSE: To propose a simple method to correct vascular input function (VIF) due to inflow effects and to test whether the proposed method can provide more accurate VIFs for improved pharmacokinetic modeling. METHODS: A spoiled gradient echo sequence-based inflow quantification and contrast agent concentration correction method was proposed. Simulations were conducted to illustrate improvement in the accuracy of VIF estimation and pharmacokinetic fitting. Animal studies with dynamic contrast-enhanced MR scans were conducted before, 1 week after, and 2 weeks after portal vein embolization (PVE) was performed in the left portal circulation of pigs...
November 10, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/29124296/-diagnostics-and-treatment-of-posterior-shoulder-instability
#9
REVIEW
M Wellmann, M-F Pastor, T Smith
Posterior shoulder instability has a markedly lower incidence than anterior shoulder instability. It has a wide spectrum of clinical symptom manifestations and the overwhelming number of patients lack a traumatic primary dislocation. In addition to a detailed medical history, a specific clinical examination with the help of standardized provocation tests is essential for the diagnostics. For the detection of structural posterior capsule and labral lesions in cases of chronic courses, magnetic resonance imaging (MRI) should be used with an intra-articular contrast agent...
November 9, 2017: Der Unfallchirurg
https://www.readbyqxmd.com/read/29121075/functional-evaluation-of-therapeutic-response-of-hcc827-lung-cancer-to-bevacizumab-and-erlotinib-targeted-therapy-using-dynamic-contrast-enhanced-and-diffusion-weighted-mri
#10
Yi-Fang Chen, Ang Yuan, Kuan-Hung Cho, Yi-Chien Lu, Mark Yen-Ping Kuo, Jyh-Horng Chen, Yeun-Chung Chang
This study aimed to investigate the therapeutic responses of lung cancer mice models with adenocarcinoma HCC827 (gefitinib sensitive) and HCC827R (gefitinib resistant) to the epidermal growth factor receptor-tyrosine kinase inhibitor erlotinib alone and in combination with the anti-angiogenesis agent bevacizumab using dynamic contrast enhanced (DCE) and diffusion-weighted MRI. In the HCC827 model, temporal changes in DCE-MRI derived parameters (Ktrans, kep, and iAUC90) and apparent diffusion coefficient (ADC) were significantly correlated with tumor size...
2017: PloS One
https://www.readbyqxmd.com/read/29120077/self-assembled-nanomicelles-as-mri-blood-pool-contrast-agent
#11
Andrej Babic, Vassily Vorobiev, Celine Xayaphoummine, Gaelle Lapicorey, Anne-Sophie Chauvin, Lothar Helm, Eric Allémann
Gadolinium-loaded nanomicelles show promise as future magnetic resonance imaging (MRI) contrast agents (CAs). Their increased size and high gadolinium (Gd) loading gives them an edge in proton relaxivity over smaller molecular Gd-complexes. Their size and stealth properties are fundamental for their long blood residence time opening the possibility for use as blood-pool contrast agents. Using L-tyrosine as a three-functional scaffold we synthesized a nanostructure building block 8. The double C18 aliphatic chain on one side, Gd-DO3A with access to bulk water in the center and 2 kDa PEG on the hydrophilic side gave the amphiphilic properties required for the core-shell nanomicellar architecture...
November 9, 2017: Chemistry: a European Journal
https://www.readbyqxmd.com/read/29118910/feasibility-of-magnetic-resonance-redox-imaging-at-low-magnetic-field-comparison-at-1-t-and-7-t
#12
Mizuki Nakamura, Sayaka Shibata, Toshihide Yamasaki, Megumi Ueno, Ikuo Nakanishi, Ken-Ichiro Matsumoto, Tadashi Kamada, Ken-Ichi Yamada, Ichio Aoki
The effect of different static magnetic field strengths, 1 T or 7 T, on the quality of nitroxyl radical-based magnetic resonance redox imaging (MRRI) was examined. A stable nitroxyl radical, 3-methoxycarbonyl-2,2,5,5-tetramethylpyrrolidine-N-oxyl (MC-PROXYL), was used as a T1 contrast agent. Phantoms and animals were scanned at 1 T and 7 T using a similar gradient echo sequence. The quality of T1-weighted images and susceptibility of T1-weighted signals were compared. The nitroxyl radical-based T1-weighted signal enhancement ratio was higher at 1 T compared with at 7 T when the identical phantom was scanned using a similar gradient echo sequence...
2017: American Journal of Translational Research
https://www.readbyqxmd.com/read/29116748/mno2-functionalized-co-p-nanocomposite-a-new-theranostic-agent-for-ph-triggered-t1-t2-dual-modality-magnetic-resonance-imaging-guided-chemo-photothermal-synergistic-therapy
#13
Longhai Jin, Jianhua Liu, Ying Tang, Lanqing Cao, Tianqi Zhang, Qinghai Yuan, Yinghui Wang, Hongjie Zhang
Construction of stimuli-responsive theranostic nanoagents that can improve the sensitivity of diagnostic imaging and boost the therapeutic efficiency has been demostrated to a promising approach for cancer diagnosis and treatment. Herein, we constructed a novel theranostic agent with Co-P nanocomposites as core, mesoporous silica as shell, and MnO2 nanosheets as "gatekeeper", which have been employed for pH-activatable T1/T2 dual mode MRI-guided chemo-photothermal combination anticancer therapy in vitro and in vivo...
November 8, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/29115690/the-effects-of-intravoxel-contrast-agent-diffusion-on-the-analysis-of-dce-mri-data-in-realistic-tissue-domains
#14
Ryan T Woodall, Stephanie L Barnes, David A Hormuth, Anna G Sorace, C Chad Quarles, Thomas E Yankeelov
PURPOSE: Quantitative evaluation of dynamic contrast enhanced MRI (DCE-MRI) allows for estimating perfusion, vessel permeability, and tissue volume fractions by fitting signal intensity curves to pharmacokinetic models. These compart mental models assume rapid equilibration of contrast agent within each voxel. However, there is increasing evidence that this assumption is violated for small molecular weight gadolinium chelates. To evaluate the error introduced by this invalid assumption, we simulated DCE-MRI experiments with volume fractions computed from entire histological tumor cross-sections obtained from murine studies...
November 8, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/29110505/effects-of-contrast-enhancement-on-diffusion-weighted-imaging-and-apparent-diffusion-coefficient-measurements-in-3-t-magnetic-resonance-imaging-of-breast-lesions
#15
Valentina Cipolla, Daniele Guerrieri, Giacomo Bonito, Simone Celsa, Carlo de Felice
Background The effect of gadolinium-based contrast agents on diffusion-weighted imaging (DWI) measurements of breast lesions is still not clear. Purpose To investigate gadolinium effects on DWI and apparent diffusion coefficient (ADC) in breast lesions and normal parenchyma with 3 Tesla contrast-enhanced MRI. Material and Methods Pre- and post-contrast DWI (b = 0 and b = 1000 s/mm(2)) were acquired in 47 patients. Measured ADC values, pre- and post-contrast T2 signal intensity (T2 SI) and contrast-to-noise ratio (CNR) were compared with Wilcoxon signed-rank and rank-sum test ( P < 0...
January 1, 2017: Acta Radiologica
https://www.readbyqxmd.com/read/29110059/differentiating-focal-nodular-hyperplasia-from-hepatocellular-adenoma-is-hepatobiliary-phase-mri-hbp-mri-using-linear-gadolinium-chelates-always-useful
#16
Marion Roux, Frederic Pigneur, Laurence Baranes, Julien Calderaro, Mélanie Chiaradia, Thomas Decaens, Sandrine Kastahian, Anaïs Charles-Nelson, Lambros Tselikas, Charlotte Costentin, Alexis Laurent, Daniel Azoulay, Ariane Mallat, Alain Rahmouni, Alain Luciani
PURPOSE: To assess the value of Hepatobiliary phase MRI (HPB-MRI) to differentiate FNH and HCA, and evaluate its impact on diagnostic accuracy, diagnostic confidence, inter-observer variability, and patient clinical management. METHODS: Forty-nine patients referred for Gd-BOPTA-enhanced MRI were retrospectively included in this IRB-approved study, with a total of 119 lesions-90 FNH and 29 HCA. Two observers separately assessed in 2 distinct randomized reading sessions the performance of MRI with (HBP-MRI) or without (conventional MRI) the use of HBP images...
November 6, 2017: Abdominal Radiology
https://www.readbyqxmd.com/read/29108077/characterization-of-focal-liver-lesions-using-ceus-and-mri-with-liver-specific-contrast-media-experience-of-a-single-radiologic-center
#17
Lukas Philipp Beyer, Florian Wassermann, Benedikt Pregler, Katharina Michalik, Janine Rennert, Isabel Wiesinger, Christian Stroszczynski, Philipp Wiggermann, Ernst Michael Jung
Aim The purpose of this study was to compare contrast-enhanced ultrasound (CEUS), magnetic resonance imaging (MRI) using liver-specific contrast agent and a combination of both for the characterization of focal liver lesions (FLL). Methods 83 patients with both benign and malignant liver lesions were examined using CEUS and MRI after the intravenous administration of liver-specific contrast media. All patients had inconclusive results from prior imaging examinations. Histopathological specimens could be obtained in 53 patients...
November 6, 2017: Ultraschall in der Medizin
https://www.readbyqxmd.com/read/29107217/ultrasensitive-mri-detection-of-spontaneous-pancreatic-tumors-with-nanocage-based-targeted-contrast-agent
#18
Takahito Kawano, Masaharu Murata, Jeong-Hun Kang, Jing Shu Piao, Sayoko Narahara, Fuminori Hyodo, Nobuhito Hamano, Jie Guo, Susumu Oguri, Kenoki Ohuchida, Makoto Hashizume
Contrast agents with greater specificity and sensitivity are required for the diagnosis of pancreatic cancers by magnetic resonance imaging (MRI). In this study, small heat shock protein 16.5 (Hsp16.5)-based nanocages conjugated to gadolinium(III)-chelated contrast agents and iRGD peptides (which target neuropilin-1 expressed on pancreatic cancer cells) were developed. To investigate whether template size influences relaxivity, nanocages with one to four hydrophobic domains were designed. MRI data showed that larger nanocages had higher T1 relaxivity than smaller nanocages, which resulted from a reduction in molecular tumbling rates caused by an increase in nanocage size, and a robust cage structure resulting from the introduction of hydrophobic domains...
October 20, 2017: Biomaterials
https://www.readbyqxmd.com/read/29106751/fast-na-k-pump-driven-steady-state-transcytolemmal-water-exchange-in-neuronal-tissue-a-study-of-rat-brain-cortical-cultures
#19
Ruiliang Bai, Charles S Springer, Dietmar Plenz, Peter J Basser
PURPOSE: Water homeostasis and transport play important roles in brain function (e.g., ion homeostasis, neuronal excitability, cell volume regulation, etc.). However, specific mechanisms of water transport across cell membranes in neuronal tissue have not been completely elaborated. METHODS: The kinetics of transcytolemmal water exchange were measured in neuronal tissue using simultaneous, real-time fluorescence and nuclear magnetic resonance (NMR) measurements of perfused, active brain organotypic cortical cultures...
November 6, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/29104741/lymph-node-imaging-in-initial-staging-of-prostate-cancer-an-overview-and-update
#20
REVIEW
Jessica G Zarzour, Sam Galgano, Jonathan McConathy, John V Thomas, Soroush Rais-Bahrami
Accurate nodal staging at the time of diagnosis of prostate cancer is crucial in determining a treatment plan for the patient. Pelvic lymph node dissection is the most reliable method, but is less than perfect and has increased morbidity. Cross sectional imaging with computed tomography (CT) and magnetic resonance imaging (MRI) are non-invasive tools that rely on morphologic characteristics such as shape and size of the lymph nodes. However, lymph nodes harboring metastatic disease may be normal sized and non-metastatic lymph nodes may be enlarged due to reactive hyperplasia...
October 28, 2017: World Journal of Radiology
keyword
keyword
41270
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"