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https://www.readbyqxmd.com/read/28346073/detection-of-clinically-significant-prostate-cancer-short-dual-pulse-sequence-versus-standard-multiparametric-mr-imaging-a-multireader-study
#1
Borna K Barth, Pieter J L De Visschere, Alexander Cornelius, Carlos Nicolau, Hebert Alberto Vargas, Daniel Eberli, Olivio F Donati
Purpose To compare the diagnostic performance of a short dual-pulse sequence magnetic resonance (MR) imaging protocol versus a standard six-pulse sequence multiparametric MR imaging protocol for detection of clinically significant prostate cancer. Materials and Methods This HIPAA-compliant study was approved by the regional ethics committee. Between July 2013 and March 2015, 63 patients from a prospectively accrued study population who underwent MR imaging of the prostate including transverse T1-weighted; transverse, coronal, and sagittal T2-weighted; diffusion-weighted; and dynamic contrast material-enhanced MR imaging with a 3-T imager at a single institution were included in this retrospective study...
March 27, 2017: Radiology
https://www.readbyqxmd.com/read/28344811/the-role-of-imaging-in-the-diagnosis-of-primary-prostate-cancer
#2
Hugh Harvey, Nandita M deSouza
Ultrasound and magnetic resonance imaging (MRI) are key imaging modalities in prostate cancer diagnosis. MRI offers a range of intrinsic contrast mechanisms (T2, diffusion-weighted imaging (DWI), MR spectroscopy (MRS)) and extrinsic contrast-generating options based on tumour vascular state following injection of weakly paramagnetic agents such as gadolinium. Together these parameters are referred to as multiparametric (mp)MRI and are used for detecting and guiding biopsy and staging prostate cancer. Although sensitivity of mpMRI is <75% for disease detection, specificity is >90% and a standardised reporting system together with MR-guided targeted biopsy is the optimal diagnostic pathway...
December 2016: Journal of Clinical Urology
https://www.readbyqxmd.com/read/28343127/direct-immobilization-of-manganese-chelates-on-silica-nanospheres-for-mri-applications
#3
Marcell Pálmai, Adrienn Pethő, Lívia Naszályi Nagy, Szilvia Klébert, Zoltán May, Judith Mihály, András Wacha, Katalin Jemnitz, Zsuzsanna Veres, Ildikó Horváth, Krisztián Szigeti, Domokos Máthé, Zoltán Varga
The development of tissue specific magnetic resonance imaging (MRI) contrast agents (CAs) is very desirable to achieve high contrast ratio combined with excellent anatomical details. To this end, we introduce a highly effective manganese(II) containing silica material, with the aim to shorten the longitudinal (T1) relaxation time. The microporous silica nanospheres (MSNSs) with enlarged porosity and specific surface area were prepared by a surfactant assisted aqueous method. Subsequently, the surface silanol groups were amino-functionalized, reacted with diethylenetriaminepentaacetic (DTPA) dianhydride and finally deposited with Mn(2+)...
March 14, 2017: Journal of Colloid and Interface Science
https://www.readbyqxmd.com/read/28342107/interactive-segmentation-in-mri-for-orthopedic-surgery-planning-bone-tissue
#4
Firat Ozdemir, Neerav Karani, Philipp Fürnstahl, Orcun Goksel
PURPOSE: Planning orthopedic surgeries is commonly performed in computed tomography (CT) images due to the higher contrast of bony structure. However, soft tissues such as muscles and ligaments that may determine the functional outcome of a procedure are not easy to identify in CT, for which fast and accurate segmentation in MRI would be desirable. To be usable in daily practice, such method should provide convenient means of interaction for modifications and corrections, e.g., during perusal by the surgeon or the planning physician for quality control...
March 24, 2017: International Journal of Computer Assisted Radiology and Surgery
https://www.readbyqxmd.com/read/28341715/can-mri-visual-assessment-differentiate-the-variants-of-primary-progressive-aphasia
#5
S A Sajjadi, N Sheikh-Bahaei, J Cross, J H Gillard, D Scoffings, P J Nestor
BACKGROUND AND PURPOSE: Primary-progressive aphasia is a clinically and pathologically heterogeneous condition. Nonfluent, semantic, and logopenic are the currently recognized clinical variants. The recommendations for the classification of primary-progressive aphasia have advocated variant-specific patterns of atrophy. The aims of the present study were to evaluate the sensitivity and specificity of the proposed imaging criteria and to assess the intra- and interrater reporting agreements...
March 24, 2017: AJNR. American Journal of Neuroradiology
https://www.readbyqxmd.com/read/28341390/pulmonary-mr-angiography-and-perfusion-imaging-a-review-of-methods-and-applications
#6
REVIEW
Christopher S Johns, Andrew J Swift, Paul J C Hughes, Yoshiharu Ohno, Mark Schiebler, Jim M Wild
The pulmonary vasculature and its role in perfusion and gas exchange is an important consideration in many conditions of the lung and heart. Currently the mainstay of imaging of the vasculature and perfusion of the lungs lies with CT and nuclear medicine perfusion scans, both of which require ionizing radiation exposure. Improvements in MRI techniques have increased the use of MRI in pulmonary vascular imaging. Here we review MRI methods for imaging the pulmonary vasculature and pulmonary perfusion, both using contrast enhanced and non-contrast enhanced methodology...
January 2017: European Journal of Radiology
https://www.readbyqxmd.com/read/28340008/pre-treatment-interleukin-6-levels-strongly-affect-bone-erosion-progression-and-repair-detected-by-magnetic-resonance-imaging-in-rheumatoid-arthritis-patients
#7
Yasushi Kondo, Yuko Kaneko, Hiroaki Sugiura, Shunsuke Matsumoto, Naoshi Nishina, Masataka Kuwana, Masahiro Jinzaki, Tsutomu Takeuchi
Objective.: To examine the relationship between MRI structural damage and repair and plasma inflammatory cytokines in patients with RA. Methods.: A total of 88 newly diagnosed, untreated RA patients were enrolled. Contrast MRI of the dominant hand and X-rays of the hands and feet were performed at baseline and 1 year later. MR images were evaluated using RA MRI scoring, and X-ray. were assessed by the modified total Sharp score. Erosion progression was defined as changes in RA MRI scoring erosion or modified total Sharp score erosion of >0...
March 8, 2017: Rheumatology
https://www.readbyqxmd.com/read/28337970/quantum-coherence-phenomenon-in-disordered-bi2sete2-topological-single-crystal-effect-of-annealing
#8
E P Amaladass, T R Devidas, Shilpam Sharma, Awadhesh Mani
We report a comparative magnetotransport study on pristine and annealed Bi2SeTe2 single crystals. The pristine sample shows a metallic trend from 300 to 180 K, and an insulating behavior for T  <  180 K, whereas the annealed sample exhibits an insulating nature in the entire 4.2-300 K temperature range. Magnetoresistance (MR) of pristine and annealed samples reveals contrasting behaviour as a function of temperature (T) and magnetic field (B). At 4.2 K, the pristine sample shows weak antilocalization (WAL) behavior at low fields and transforms to weak localization (WL) behavior (negative MR) for B  >  2...
March 24, 2017: Journal of Physics. Condensed Matter: An Institute of Physics Journal
https://www.readbyqxmd.com/read/28336868/eu-gd-codoped-yttria-nanoprobes-for-optical-and-t%C3%A2-weighted-magnetic-resonance-imaging
#9
Timur Sh Atabaev, Jong Ho Lee, Yong Cheol Shin, Dong-Wook Han, Ki Seok Choo, Ung Bae Jeon, Jae Yeon Hwang, Jeong A Yeom, Hyung-Kook Kim, Yoon-Hwae Hwang
Nanoprobes with multimodal functionality have attracted significant interest recently because of their potential applications in nanomedicine. This paper reports the successful development of lanthanide-doped Y₂O₃ nanoprobes for potential applications in optical and magnetic resonance (MR) imaging. The morphology, structural, and optical properties of these nanoprobes were characterized by transmission electron microscope (TEM), field emission scanning electron microscope (FESEM), X-ray diffraction (XRD), energy-dispersive X-ray (EDX), and photoluminescence (PL)...
February 10, 2017: Nanomaterials
https://www.readbyqxmd.com/read/28336427/high-resolution-anatomical-and-quantitative-mri-of-the-entire-human-occipital-lobe-ex-vivo-at-9-4t
#10
S Sengupta, F J Fritz, R L Harms, S Hildebrand, D H Y Tse, B A Poser, R Goebel, A Roebroeck
Several magnetic resonance imaging (MRI) contrasts are sensitive to myelin content in gray matter in vivo which has ignited ambitions of MRI-based in vivo cortical histology. Ultra-high field (UHF) MRI, at fields of 7T and beyond, is crucial to provide the resolution and contrast needed to sample contrasts over the depth of the cortex and get closer to layer resolved imaging. Ex vivo MRI of human post mortem samples is an important stepping stone to investigate MRI contrast in the cortex, validate it against histology techniques applied in situ to the same tissue, and investigate the resolutions needed to translate ex vivo findings to in vivo UHF MRI...
March 20, 2017: NeuroImage
https://www.readbyqxmd.com/read/28334490/mr-cholangiography-in-potential-liver-donors-quantitative-and-qualitative-improvement-with-administration-of-an-oral-effervescent-agent
#11
Heon-Ju Kwon, Kyoung Won Kim, Sang Hyun Choi, Jin-Hee Jung, So Yeon Kim, Se-Young Kim, Jeongjin Lee, Dong-Hwan Jung, Tae-Yong Ha, Gi-Won Song, Sung-Gyu Lee
PURPOSE: To determine whether an oral effervescent agent improves magnetic resonance cholangiography (MRC) images, both qualitatively and quantitatively, in potential live liver donors. MATERIALS AND METHODS: This retrospective study was approved by the Institutional Review Board, and informed consent was waived. Seventy potential liver donors underwent 2D MRC before and after administration of an oral effervescent agent. One radiologist measured relative contrast ratio (rC) and relative signal intensity (rS) for right and left intrahepatic ducts (RHD and LHD), and common hepatic duct (CHD)...
March 23, 2017: Journal of Magnetic Resonance Imaging: JMRI
https://www.readbyqxmd.com/read/28333623/a-comparison-of-fem-based-inversion-algorithms-local-frequency-estimation-and-direct-inversion-approach-used-in-mr-elastography
#12
Mohammad Honarvar, Ramin Sahebjavaher, Robert Rohling, Septimiu Salcudean
In quantitative elastography, maps of the mechanical properties of soft tissue, or elastograms, are calculated from the measured displacement data by solving an inverse problem. The model assumptions have a significant effect on elastograms. Motivated by the high sensitivity of imaging results to the model assumptions for in-vivo Magnetic Resonance Elastography (MRE) of the prostate, we compared elastograms obtained with four different methods. Two FEM-based methods developed by our group were compared with two other commonly used methods, Local Frequency Estimator (LFE) and curl-based Direct Inversion (c-DI)...
March 22, 2017: IEEE Transactions on Medical Imaging
https://www.readbyqxmd.com/read/28330019/facial-nerve-tractography-a-new-tool-to-detect-perineural-invasion-in-parotid-cancers
#13
René-Charles Rouchy, Arnaud Attyé, Irène Troprès, Maud Medici, Adrian Kastler, Christian Righini, Alexandre Krainik
PURPOSE: To determine whether magnetic resonance (MR) tractography of facial nerve (VIIn) is useful to detect perineural invasion in case of parotid cancers. MATERIALS AND METHODS: Thirty patients, aged 18 or over, were enrolled in this prospective study between December 2013 and March 2016 (IRB 5891), with a diagnosis of parotid tumors (15 malignant, 15 benign). They have undergone preoperative MR scans (3.0-T) before surgical management. The parameters of the diffusion-weighted (DW) sequence were b-value of 1000s/mm(2); 32 directions; voxel size: 2mm isotropic; scan time: 9' The post-processing generates whole-neck constrained spherical deconvolution (CSD)-based tractography data and super-resolution track-weighted imaging (TWI) technique...
March 2017: Journal of Neuroradiology. Journal de Neuroradiologie
https://www.readbyqxmd.com/read/28329173/mitral-valve-repair-for-secondary-mitral-regurgitation-in-non-ischaemic-dilated-cardiomyopathy-is-associated-with-left-ventricular-reverse-remodelling-and-increase-of-forward-flow
#14
Vasileios Kamperidis, Suzanne E van Wijngaarden, Philippe J van Rosendael, William Kok Fai Kong, Madelien V Regeer, Frank van der Kley, Georgios Sianos, Nina Ajmone Marsan, Jeroen J Bax, Victoria Delgado
Aims: It remains unclear whether surgical or transcatheter mitral valve repair for secondary mitral regurgitation (MR) in patients with non-ischaemic cardiomyopathy reverse the underlying left ventricular (LV) pathophysiology. We hypothesized that mitral valve repair improves LV systolic function and forward flow and induces LV reverse remodelling in this group of patients. Methods and results: Seventy-six patients (65 ± 14 years old, 43% male) with non-ischaemic cardiomyopathy and moderate to severe chronic secondary MR treated successfully with transcatheter or surgical mitral valve repair were evaluated...
February 23, 2017: European Heart Journal Cardiovascular Imaging
https://www.readbyqxmd.com/read/28327002/use-of-imaging-to-predict-complete-response-of-colorectal-liver-metastases-after-chemotherapy-mr-imaging-versus-ct-imaging
#15
Min Jung Park, Nurhee Hong, Kyunghwa Han, Min Ju Kim, Yoon Jin Lee, Yang Shin Park, Sung Eun Rha, Sumi Park, Won Jae Lee, Seong Ho Park, Chang Hee Lee, Chung Mo Nam, Chansik An, Hye Jin Kim, Honsoul Kim, Mi-Suk Park
Purpose To compare the diagnostic performances of contrast agent-enhanced computed tomography (CT) and gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid-enhanced liver magnetic resonance (MR) imaging (referred to as EOB MR imaging) in the evaluation of disappearing colorectal liver metastases (CRLMs) after chemotherapy. Materials and Methods The eight institutional review boards approved this retrospective study and waived the requirement for informed consent. On the basis of retrospective searches in eight hospitals, 87 patients with 393 CRLMs, each patient with one or more CRLM that later disappeared on contrast-enhanced CT scans after chemotherapy, and subsequently underwent surgery for the CRLMs, were enrolled...
March 22, 2017: Radiology
https://www.readbyqxmd.com/read/28321246/medical-image-fusion-based-on-feature-extraction-and-sparse-representation
#16
Yin Fei, Gao Wei, Song Zongxi
As a novel multiscale geometric analysis tool, sparse representation has shown many advantages over the conventional image representation methods. However, the standard sparse representation does not take intrinsic structure and its time complexity into consideration. In this paper, a new fusion mechanism for multimodal medical images based on sparse representation and decision map is proposed to deal with these problems simultaneously. Three decision maps are designed including structure information map (SM) and energy information map (EM) as well as structure and energy map (SEM) to make the results reserve more energy and edge information...
2017: International Journal of Biomedical Imaging
https://www.readbyqxmd.com/read/28319464/the-dr-jekyll-and-mr-hyde-complexity-of-the-macrophage-response-in-disease
#17
Danielle Y F Twum, Lauren Burkard-Mandel, Scott I Abrams
Macrophages comprise a highly diverse cell population expressing a continuum of biologic activities dictated by exposure to a plethora of inflammatory cues. Moreover, in contrast to most other hematopoietic populations, macrophages can arise from multiple sites-namely, the bone marrow or yolk sac, adding to the complexity of macrophage biology during health and disease. Nonetheless, it is this very type of diversity that is indispensable for macrophages to respond effectively to pathologic insults. Most of the interest in macrophage biology has been devoted to bone marrow-derived populations, but it is now becoming clearer that tissue-resident populations, which arise from distinct hematopoietic compartments, serve critical roles in host defense, including protection against neoplastic disease...
February 13, 2017: Journal of Leukocyte Biology
https://www.readbyqxmd.com/read/28317859/physiological-and-transcriptional-approaches-reveal-connection-between-nitrogen-and-manganese-cycles-in-shewanella-algae-c6g3
#18
Axel Aigle, Patricia Bonin, Chantal Iobbi-Nivol, Vincent Méjean, Valérie Michotey
To explain anaerobic nitrite/nitrate production at the expense of ammonium mediated by manganese oxide (Mn(IV)) in sediment, nitrate and manganese respirations were investigated in a strain (Shewanella algae C6G3) presenting these features. In contrast to S. oneidensis MR-1, a biotic transitory nitrite accumulation at the expense of ammonium was observed in S. algae during anaerobic growth with Mn(IV) under condition of limiting electron acceptor, concomitantly, with a higher electron donor stoichiometry than expected...
March 20, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28317128/comparison-of-dce-mri-kinetic-parameters-and-fmiso-pet-uptake-parameters-in-head-and-neck-cancer-patients
#19
Urban Simoncic, Sara Leibfarth, Stefan Welz, Nina Schwenzer, Holger Schmidt, Gerald Reischl, Christina Pfannenberg, Christian la Fougère, Konstantin Nikolaou, Daniel Zips, Daniela Thorwarth
PURPOSE: Tumour hypoxia is a major cause of radiation resistance, often present in various solid tumours. Dynamic [(18) F]-fluoromisonidazole (FMISO) PET imaging is able to reliably assess tumour hypoxia. Comprehensive characterization of tumour microenvironment through FMISO-PET and dynamic contrast enhanced (DCE) MR multimodality imaging might be a valuable alternative to the dynamic FMISO-PET acquisition. The aim of this work was to explore the correlation between the FMISO-PET and DCE-MRI kinetic parameters...
March 20, 2017: Medical Physics
https://www.readbyqxmd.com/read/28306727/biodistribution-and-pet-imaging-of-pharmacokinetics-of-manganese-in-mice-using-manganese-52
#20
A Lake Wooten, Tolulope A Aweda, Benjamin C Lewis, Rebecca B Gross, Suzanne E Lapi
Manganese is essential to life, and humans typically absorb sufficient quantities of this element from a normal healthy diet; however, chronic, elevated ingestion or inhalation of manganese can be neurotoxic, potentially leading to manganism. Although imaging of large amounts of accumulated Mn(II) is possible by MRI, quantitative measurement of the biodistribution of manganese, particularly at the trace level, can be challenging. In this study, we produced the positron-emitting radionuclide 52Mn (t1/2 = 5.6 d) by proton bombardment (Ep<15 MeV) of chromium metal, followed by solid-phase isolation by cation-exchange chromatography...
2017: PloS One
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