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https://www.readbyqxmd.com/read/28651276/white-paper-interventional-mri-current-status-and-potential-for-development-considering-economic-perspectives-part-1-general-application
#1
Jörg Barkhausen, Thomas Kahn, Gabriele A Krombach, Christiane K Kuhl, Joachim Lotz, David Maintz, Jens Ricke, Stefan O Schönberg, Thomas J Vogl, Frank K Wacker
Background MRI is attractive for the guiding and monitoring of interventional procedures due to its high intrinsic soft tissue contrast and the possibility to measure physiologic parameters like flow and cardiac function. Method The current status of interventional MRI for the clinical routine was analyzed. Results The effort needed for the development of MR-safe monitoring systems and instruments initially resulted in the application of interventional MRI only for procedures that could not be performed by other means...
July 2017: RöFo: Fortschritte Auf Dem Gebiete der Röntgenstrahlen und der Nuklearmedizin
https://www.readbyqxmd.com/read/28650621/novel-cdta-based-bifunctional-chelators-for-stable-and-inert-mn-ii-complexation-synthesis-and-physicochemical-characterization
#2
Christian Vanasschen, Enikő Molnár, Gyula Tircsó, Ferenc K Kálmán, Éva Tóth, Marie Brandt, Heinz H Coenen, Bernd Neumaier
In the search for Mn(II) MR and PET/MR imaging agents with optimal balance between thermodynamic stability, kinetic inertness, and relaxivity, two novel bifunctional Mn(II) chelators (BFMnCs) based on CDTA (trans-1,2-diaminocyclohexane-N,N,N',N'-tetraacetic acid) were synthesized. A six-step synthesis, involving the buildup of a functionalized trans-1,2-diaminocyclohexane core, provided CuAAC-reactive 6a and 6b bearing an alkyne or azide substituent on the cyclohexane ring, respectively (CuAAC = Cu(I)-catalyzed azide-alkyne 1,3-dipolar cycloaddition)...
June 26, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/28649156/multi-atlas-segmentation-enables-robust-multi-contrast-mri-spleen-segmentation-for-splenomegaly
#3
Yuankai Huo, Jiaqi Liu, Zhoubing Xu, Robert L Harrigan, Albert Assad, Richard G Abramson, Bennett A Landman
Non-invasive spleen volume estimation is essential in detecting splenomegaly. Magnetic resonance imaging (MRI) has been used to facilitate splenomegaly diagnosis in vivo. However, achieving accurate spleen volume estimation from MR images is challenging given the great inter-subject variance of human abdomens and wide variety of clinical images/modalities. Multi-atlas segmentation has been shown to be a promising approach to handle heterogeneous data and difficult anatomical scenarios. In this paper, we propose to use multi-atlas segmentation frameworks for MRI spleen segmentation for splenomegaly...
February 11, 2017: Proceedings of SPIE
https://www.readbyqxmd.com/read/28646593/mri-assisted-dual-motion-correction-for-myocardial-perfusion-defect-detection-in-pet-imaging
#4
Xinhui Wang, Arman Rahmim, Jing Tang
PURPOSE: Myocardial perfusion (MP) PET imaging is a powerful tool in risk assess-assessment and stratification of patients with coronary artery disease. Involuntary organmotion degrades cardiac PET image resolution while respiratory and/or cardiac gating to freeze the motion leads to noisier reconstructed images due to reduced counts in the gated frames. In this work, we propose an MRI assisted dual motion correction method to compensate for respiratory and cardiac motion in MP PET data and study the impact of dual motion correction on MP defect detection using systematically designed experiments...
June 24, 2017: Medical Physics
https://www.readbyqxmd.com/read/28644905/a-realistic-phantom-for-validating-mri-based-synthetic-ct-images-of-the-human-skull
#5
Abraam S Soliman, Levi Burns, Amir Owrangi, Young Lee, William Y Song, Greg Stanisz, Brige P Chugh
PURPOSE: To introduce a new realistic human skull phantom for the validation of synthetic CT images of cortical bone from ultra-short echo-time (UTE) sequences. METHODS AND MATERIALS: A human skull of an adult female was utilized as a realistic representation of skull cortical bone. The skull was stabilized in a special acrylic container and was filled with contrast agents that have T1 and T2 relaxation times similar to human brain. The phantom was MR scanned at 3T with UTE and T2 -weighted sequences, followed by CT...
June 23, 2017: Medical Physics
https://www.readbyqxmd.com/read/28643777/in-situ-targeted-mri-detection-of-helicobacter-pylori-with-stable-magnetic-graphitic-nanocapsules
#6
Yunjie Li, Xiaoxiao Hu, Ding Ding, Yuxiu Zou, Yiting Xu, Xuewei Wang, Yin Zhang, Long Chen, Zhuo Chen, Weihong Tan
Helicobacter pylori infection is implicated in the aetiology of many diseases. Despite numerous studies, a painless, fast and direct method for the in situ detection of H. pylori remains a challenge, mainly due to the strong acidic/enzymatic environment of the gastric mucosa. Herein, we report the use of stable magnetic graphitic nanocapsules (MGNs), for in situ targeted magnetic resonance imaging (MRI) detection of H. pylori. Several layers of graphene as the shell effectively protect the magnetic core from corrosion while retaining the superior contrast effect for MRI in the gastric environment...
June 15, 2017: Nature Communications
https://www.readbyqxmd.com/read/28643383/multiecho-pseudo-golden-angle-stack-of-stars-thermometry-with-high-spatial-and-temporal-resolution-using-k-space-weighted-image-contrast
#7
Bryant T Svedin, Allison Payne, Bradley D Bolster, Dennis L Parker
PURPOSE: Implement and evaluate a 3D MRI method to measure temperature changes with high spatial and temporal resolution and large field of view. METHODS: A multiecho pseudo-golden angle stack-of-stars (SOS) sequence with k-space weighted image contrast (KWIC) reconstruction was implemented to simultaneously measure multiple quantities, including temperature, initial signal magnitude M(0), transverse relaxation time ( T2*), and water/fat images. Respiration artifacts were corrected using self-navigation...
June 22, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/28643295/fat-suppression-techniques-for-breast-mri-dixon-versus-spectral-fat-saturation-for-3d-t1-weighted-at-3%C3%A2-t
#8
Anastasia Kalovidouri, Natacha Firmenich, Benedicte M A Delattre, Marlise Picarra, Christoph D Becker, Xavier Montet, Diomidis Botsikas
OBJECTIVE: To compare two fat suppression techniques used for 3D T1-weighted sequence in breast MRI (magnetic resonance imaging), namely Dixon versus spectral fat saturation (fat sat). MATERIALS AND METHODS: All breast MRI examinations performed in a Philips 3 T unit between March 2013 and October 2015 including either a Dixon or a fat sat sequence were retrospectively analyzed. The examinations were subjectively evaluated by two independent experienced readers in a scale of 5 for overall quality of fat suppression, homogeneity of fat suppression, definition of anatomic structures and focal lesions, diagnostic confidence for axillary and internal mammary regions and the presence of artifacts, 1 corresponding to excellent and 5 to non-diagnostic quality...
June 22, 2017: La Radiologia Medica
https://www.readbyqxmd.com/read/28642266/t1-signal-measurements-in-pediatric-brain-findings-after-multiple-exposures-to-gadobenate-dimeglumine-for-imaging-of-nonneurologic-disease
#9
G K Schneider, J Stroeder, G Roditi, C Colosimo, P Armstrong, M Martucci, A Buecker, P Raczeck
BACKGROUND AND PURPOSE: Signal intensity increases possibly suggestive of gadolinium retention have recently been reported on unenhanced T1-weighted images of the pediatric brain following multiple exposures to gadolinium-based MR contrast agents. Our aim was to determine whether T1 signal changes suggestive of gadolinium deposition occur in the brains of pediatric nonneurologic patients after multiple exposures to gadobenate dimeglumine. MATERIALS AND METHODS: Thirty-four nonneurologic patients (group 1; 17 males/17 females; mean age, 7...
June 22, 2017: AJNR. American Journal of Neuroradiology
https://www.readbyqxmd.com/read/28642265/the-initial-area-under-the-curve-derived-from-dynamic-contrast-enhanced-mri-improves-prognosis-prediction-in-glioblastoma-with-unmethylated-mgmt-promoter
#10
Y S Choi, S S Ahn, H-J Lee, J H Chang, S-G Kang, E H Kim, S H Kim, S-K Lee
BACKGROUND AND PURPOSE: Although perfusion and permeability MR parameters have known to have prognostic value, they have reproducibility issues. Our aim was to evaluate whether the initial area under the time-to-signal intensity curve (IAUC) derived from dynamic contrast-enhanced MR imaging can improve prognosis prediction in patients with glioblastoma with known MGMT status. MATERIALS AND METHODS: We retrospectively examined 88 patients with glioblastoma who underwent preoperative dynamic contrast-enhanced MR imaging...
June 22, 2017: AJNR. American Journal of Neuroradiology
https://www.readbyqxmd.com/read/28641819/dynamic-contrast-enhanced-mr-imaging-of-carotid-vasa-vasorum-in-relation-to-coronary-and-cerebrovascular-events
#11
Juan Wang, Huijun Chen, Jie Sun, Daniel S Hippe, Huawei Zhang, Shengyuan Yu, Jianming Cai, Leixing Xie, Bao Cui, Chun Yuan, Xihai Zhao, Weimin Yuan, Hongbin Liu
BACKGROUND AND AIMS: Dynamic contrast-enhanced MR imaging (DCE-MRI) provides a noninvasive approach to the functional status of carotid adventitial vasa vasorum. Contrast extravasation rate, or K(trans), derived from kinetic modeling of adventitial enhancement, has been correlated with plaque neovascularization and inflammation. This study sought to clarify the clinical implications of K(trans) by evaluating its relationship with documented cardiovascular events (CVE). METHODS: Seventy patients with carotid plaque at clinical ultrasound examination were recruited and imaged with a previously-described bright-blood DCE-MRI protocol (spatial resolution: 0...
June 3, 2017: Atherosclerosis
https://www.readbyqxmd.com/read/28640847/heart-rate-lowering-treatment-leads-to-a-reduction-in-vulnerable-plaque-features-in-atherosclerotic-rabbits
#12
Raf H M van Hoof, Evelien Hermeling, Judith C Sluimer, Julie Salzmann, Arnold P G Hoeks, Jérôme Roussel, Mat J A P Daemen, Harry Struijker-Boudier, Joachim E Wildberger, Sylvia Heeneman, M Eline Kooi
OBJECTIVE: To investigate the effect of a heart rate (HR) lowering agent (Ivabradine) on features of atherosclerotic plaque vulnerability with magnetic resonance imaging (MRI), ultrasound imaging, and histology. APPROACH AND RESULTS: Atherosclerosis was induced in the abdominal aorta of 19 rabbits. Nine rabbits were treated with Ivabradine (17 mg/kg/day) during the entire study period. At week 14, imaging was performed. Plaque size was quantified on contrast-enhanced T1-weighted MR images...
2017: PloS One
https://www.readbyqxmd.com/read/28640695/gadolinium-brain-deposition-after-macrocyclic-gadolinium-administration-a-pediatric-case-control-study
#13
Daniel Tibussek, Christin Rademacher, Julian Caspers, Bernd Turowski, Jörg Schaper, Gerald Antoch, Dirk Klee
Purpose To determine whether signal intensity (SI) in T1 sequences as a potential indicator of gadolinium deposition increases after repeated administration of the macrocyclic gadolinium-based contrast agents (GBCAs) gadoteridol and gadoterate meglumine in a pediatric cohort. Materials and Methods This retrospective case-control study of children with brain tumors who underwent nine or more contrast material-enhanced brain magnetic resonance (MR) imaging studies from 2008 to 2015 was approved by the local ethics board...
June 21, 2017: Radiology
https://www.readbyqxmd.com/read/28640692/comparison-of-gadolinium-concentrations-within-multiple-rat-organs-after-intravenous-administration-of-linear-versus-macrocyclic-gadolinium-chelates
#14
Robert J McDonald, Jennifer S McDonald, Daying Dai, Dana Schroeder, Mark E Jentoft, David L Murray, Ramanathan Kadirvel, Laurence J Eckel, David F Kallmes
Purpose To compare gadolinium tissue concentrations of multiple linear and macrocyclic chelates in a rat model to better understand the scope and extent of tissue deposition following multiple intravenous doses of gadolinium-based contrast agent (GBCA). Materials and Methods In this Institutional Animal Care and Use Committee-approved study, healthy rats received 20 intravenous injections of 2.5 mmol gadolinium per kilogram (gadolinium-exposed group) or saline (control group) over a 26-day period. Unenhanced T1 signal intensities of the dentate nucleus were measured from magnetic resonance (MR) images obtained prior to GBCA injection and 3 days after final injection...
June 19, 2017: Radiology
https://www.readbyqxmd.com/read/28639659/hydrothermal-and-biomineralization-synthesis-of-a-dual-modal-nanoprobe-for-targeted-near-infrared-persistent-luminescence-and-magnetic-resonance-imaging
#15
Yu Wang, Cheng-Xiong Yang, Xiu-Ping Yan
The development of the multimodal probes is of great importance for bioimaging application. Herein, we report the fabrication of a functional nanocomposite from near-infrared (NIR) persistent luminescent nanoparticles (PLNPs) and Gd2O3 as a multimodal probe for in vivo NIR persistent luminescence and magnetic resonance (MR) imaging. Small-sized monodispersed NIR ZnGa2O4:Cr(3+) PLNPs (ca. 15 nm) were prepared as the NIR persistent luminescence source by a hydrothermal method while hyaluronic acid (HA) functionalized Gd2O3 (HA-Gd2O3) was synthesized as the MR contrast agent via a biomineralization approach...
June 22, 2017: Nanoscale
https://www.readbyqxmd.com/read/28639452/-magnetic-resonance-strength-of-1-5-t-possibilities-detailed-view-of-the-optic-nerve
#16
P Hanzlíková, J Chmelová
Due to the increased availability of MRI, this modality is the first choice for patients with a suspected pathology of the optic nerve, chiasm and optic tracts. Magnetic resonance imaging allows to evaluate the optic nerve itself as well as the gain or atrophy, its focal changes; it also allows detailed views of the surrounding structures such as vagina of the optic nerve and the mutual ratio between the full thickness of the nerve and the vagina, and the nerve itself. MR method uses a tissue contrast of an adipose tissue structures to a detailed imaging of the orbit...
2017: Ceská a Slovenská Oftalmologie
https://www.readbyqxmd.com/read/28638982/image-quality-at-synthetic-brain-magnetic-resonance-imaging-in-children
#17
So Mi Lee, Young Hun Choi, Jung-Eun Cheon, In-One Kim, Seung Hyun Cho, Won Hwa Kim, Hye Jung Kim, Hyun-Hae Cho, Sun-Kyoung You, Sook-Hyun Park, Moon Jung Hwang
BACKGROUND: The clinical application of the multi-echo, multi-delay technique of synthetic magnetic resonance imaging (MRI) generates multiple sequences in a single acquisition but has mainly been used in adults. OBJECTIVE: To evaluate the image quality of synthetic brain MR in children compared with that of conventional images. MATERIALS AND METHODS: Twenty-nine children (median age: 6 years, range: 0-16 years) underwent synthetic and conventional imaging...
June 22, 2017: Pediatric Radiology
https://www.readbyqxmd.com/read/28638107/tracking-protein-function-with-sodium-multi-quantum%C3%A2-spectroscopy-in-a-3d-tissue-culture-based-on-microcavity-arrays
#18
Andreas Neubauer, Cordula Nies, Victor D Schepkin, Ruomin Hu, Matthias Malzacher, Jorge Chacón-Caldera, David Thiele, Eric Gottwald, Lothar R Schad
The aim of this study was to observe the effects of strophanthin induced inhibition of the Na-/K-ATPase in liver cells using a magnetic resonance (MR) compatible bioreactor. A microcavity array with a high density three-dimensional cell culture served as a functional magnetic resonance imaging (MRI) phantom for sodium multi quantum (MQ) spectroscopy. Direct contrast enhanced (DCE) MRI revealed the homogenous distribution of biochemical substances inside the bioreactor. NMR experiments using advanced bioreactors have advantages with respect to having full control over a variety of physiological parameters such as temperature, gas composition and fluid flow...
June 21, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28638001/comparison-between-glioblastoma-and-primary-central-nervous-system-lymphoma-using-mr-image-based-texture-analysis
#19
Akira Kunimatsu, Natsuko Kunimatsu, Kouhei Kamiya, Takeyuki Watadani, Harushi Mori, Osamu Abe
PURPOSE: To elucidate differences between glioblastoma (GBM) and primary central nervous system lymphoma (PCNSL) with magnetic resonance (MR) image-based texture features. METHODS: This was an Institutional Review Board (IRB)-approved retrospective study. Consecutive, pathologically proven, initially treated 44 patients with GBM and 16 patients with PCNSL were enrolled. We calculated a total of 67 image texture features on the largest contrast-enhancing lesion in each patient on post-contrast T1-weighted images...
June 22, 2017: Magnetic Resonance in Medical Sciences: MRMS
https://www.readbyqxmd.com/read/28636308/redox-sensitive-nanoscale-coordination-polymers-for-drug-delivery-and-cancer-theranostics
#20
Jiayue Zhao, Yu Yang, Xiao Han, Chao Liang, Jingjing Liu, Xuejiao Song, Zili Ge, Zhuang Liu
Nanoscale coordination polymers (NCPs) with inherent biodegradability, chemical diversities, and porous structures, are a promising class of nanomaterials in the nanomedicine field. Herein, a unique type of redox sensitive NCPs is constructed with manganese ions (Mn2+) and dithiodiglycolic acid as the disulfide (SS) containing organic bridging ligand. The obtained Mn-SS NCPs with mesoporous structure could be efficiently loaded with doxorubicin (DOX), a chemotherapeutics. The yielded Mn-SS/DOX nanoparticles are coated with a layer of polydopamine (PDA) and then modified by polyethylene glycol (PEG)...
June 21, 2017: ACS Applied Materials & Interfaces
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