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Sample records for dendrimer-based ph-responsive mri

  1. Dendrimer-based Macromolecular MRI Contrast Agents: Characteristics and Application

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    Hisataka Kobayashi

    2003-01-01

    Full Text Available Numerous macromolecular MRI contrast agents prepared employing relatively simple chemistry may be readily available that can provide sufficient enhancement for multiple applications. These agents operate using a ~100-fold lower concentration of gadolinium ions in comparison to the necessary concentration of iodine employed in CT imaging. Herein, we describe some of the general potential directions of macromolecular MRI contrast agents using our recently reported families of dendrimer-based agents as examples. Changes in molecular size altered the route of excretion. Smaller-sized contrast agents less than 60 kDa molecular weight were excreted through the kidney resulting in these agents being potentially suitable as functional renal contrast agents. Hydrophilic and larger-sized contrast agents were found better suited for use as blood pool contrast agents. Hydrophobic variants formed with polypropylenimine diaminobutane dendrimer cores created liver contrast agents. Larger hydrophilic agents are useful for lymphatic imaging. Finally, contrast agents conjugated with either monoclonal antibodies or with avidin are able to function as tumor-specific contrast agents, which also might be employed as therapeutic drugs for either gadolinium neutron capture therapy or in conjunction with radioimmunotherapy.

  2. Macromolecular and dendrimer-based magnetic resonance contrast agents

    Energy Technology Data Exchange (ETDEWEB)

    Bumb, Ambika; Brechbiel, Martin W. (Radiation Oncology Branch, National Cancer Inst., National Inst. of Health, Bethesda, MD (United States)), e-mail: pchoyke@mail.nih.gov; Choyke, Peter (Molecular Imaging Program, National Cancer Inst., National Inst. of Health, Bethesda, MD (United States))

    2010-09-15

    Magnetic resonance imaging (MRI) is a powerful imaging modality that can provide an assessment of function or molecular expression in tandem with anatomic detail. Over the last 20-25 years, a number of gadolinium-based MR contrast agents have been developed to enhance signal by altering proton relaxation properties. This review explores a range of these agents from small molecule chelates, such as Gd-DTPA and Gd-DOTA, to macromolecular structures composed of albumin, polylysine, polysaccharides (dextran, inulin, starch), poly(ethylene glycol), copolymers of cystamine and cystine with GD-DTPA, and various dendritic structures based on polyamidoamine and polylysine (Gadomers). The synthesis, structure, biodistribution, and targeting of dendrimer-based MR contrast agents are also discussed

  3. Emerging concepts in dendrimer-based nanomedicine: from design principles to clinical applications.

    Science.gov (United States)

    Kannan, R M; Nance, E; Kannan, S; Tomalia, D A

    2014-12-01

    Dendrimers are discrete nanostructures/nanoparticles with 'onion skin-like' branched layers. Beginning with a core, these nanostructures grow in concentric layers to produce stepwise increases in size that are similar to the dimensions of many in vivo globular proteins. These branched tree-like concentric layers are referred to as 'generations'. The outer generation of each dendrimer presents a precise number of functional groups that may act as a monodispersed platform for engineering favourable nanoparticle-drug and nanoparticle-tissue interactions. These features have attracted significant attention in medicine as nanocarriers for traditional small drugs, proteins, DNA/RNA and in some instances as intrinsically active nanoscale drugs. Dendrimer-based drugs, as well as diagnostic and imaging agents, are emerging as promising candidates for many nanomedicine applications. First, we will provide a brief survey of recent nanomedicines that are either approved or in the clinical approval process. This will be followed by an introduction to a new 'nanoperiodic' concept which proposes nanoparticle structure control and the engineering of 'critical nanoscale design parameters' (CNDPs) as a strategy for optimizing pharmocokinetics, pharmocodynamics and site-specific targeting of disease. This paradigm has led to the emergence of CNDP-directed nanoperiodic property patterns relating nanoparticle behaviour to critical in vivo clinical translation issues such as cellular uptake, transport, elimination, biodistribution, accumulation and nanotoxicology. With a focus on dendrimers, these CNDP-directed nanoperiodic patterns are used as a strategy for designing and optimizing nanoparticles for a variety of drug delivery and imaging applications, including a recent dendrimer-based theranostic nanodevice for imaging and treating cancer. Several emerging preclinical dendrimer-based nanotherapy concepts related to inflammation, neuro-inflammatory disorders, oncology and infectious

  4. Dendrimer-based fluorescent indicators: in vitro and in vivo applications.

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    Lorenzo Albertazzi

    Full Text Available BACKGROUND: The development of fluorescent proteins and synthetic molecules whose fluorescence properties are controlled by the environment makes it possible to monitor physiological and pathological events in living systems with minimal perturbation. A large number of small organic dyes are available and routinely used to measure biologically relevant parameters. Unfortunately their application is hindered by a number of limitations stemming from the use of these small molecules in the biological environment. PRINCIPAL FINDINGS: We present a novel dendrimer-based architecture leading to multifunctional sensing elements that can overcome many of these problems. Applications in vitro, in living cells and in vivo are reported. In particular, we image for the first time extracellular pH in the brain in a mouse epilepsy model. CONCLUSION: We believe that the proposed architecture can represent a useful and novel tool in fluorescence imaging that can be widely applied in conjunction with a broad range of sensing dyes and experimental setups.

  5. Highly sensitive dendrimer-based nanoplasmonic biosensor for drug allergy diagnosis.

    Science.gov (United States)

    Soler, Maria; Mesa-Antunez, Pablo; Estevez, M-Carmen; Ruiz-Sanchez, Antonio Jesus; Otte, Marinus A; Sepulveda, Borja; Collado, Daniel; Mayorga, Cristobalina; Torres, Maria Jose; Perez-Inestrosa, Ezequiel; Lechuga, Laura M

    2015-04-15

    A label-free biosensing strategy for amoxicillin (AX) allergy diagnosis based on the combination of novel dendrimer-based conjugates and a recently developed nanoplasmonic sensor technology is reported. Gold nanodisks were functionalized with a custom-designed thiol-ending-polyamido-based dendron (d-BAPAD) peripherally decorated with amoxicilloyl (AXO) groups (d-BAPAD-AXO) in order to detect specific IgE generated in patient's serum against this antibiotic during an allergy outbreak. This innovative strategy, which follows a simple one-step immobilization procedure, shows exceptional results in terms of sensitivity and robustness, leading to a highly-reproducible and long-term stable surface which allows achieving extremely low limits of detection. Moreover, the viability of this biosensor approach to analyze human biological samples has been demonstrated by directly analyzing and quantifying specific anti-AX antibodies in patient's serum without any sample pretreatment. An excellent limit of detection (LoD) of 0.6ng/mL (i.e. 0.25kU/L) has been achieved in the evaluation of clinical samples evidencing the potential of our nanoplasmonic biosensor as an advanced diagnostic tool to quickly identify allergic patients. The results have been compared and validated with a conventional clinical immunofluorescence assay (ImmunoCAP test), confirming an excellent correlation between both techniques. The combination of a novel compact nanoplasmonic platform and a dendrimer-based strategy provides a highly sensitive label free biosensor approach with over two times better detectability than conventional SPR. Both the biosensor device and the carrier structure hold great potential in clinical diagnosis for biomarker analysis in whole serum samples and other human biological samples. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Paramagnetic NMR investigation of dendrimer-based host-guest interactions.

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    Fei Wang

    Full Text Available In this study, the host-guest behavior of poly(amidoamine (PAMAM dendrimers bearing amine, hydroxyl, or carboxylate surface functionalities were investigated by paramagnetic NMR studies. 2,2,6,6-Tetramethylpiperidinyloxy (TEMPO derivatives were used as paramagnetic guest molecules. The results showed that TEMPO-COOH significantly broaden the ¹H NMR peaks of amine- and hydroxyl-terminated PAMAM dendrimers. In comparison, no paramagnetic relaxation enhancement (PRE was observed between TEMPO-NH₂, TEMPO-OH and the three types of PAMAM dendrimers. The PRE phenomenon observed is correlated with the encapsulation of TEMPO-COOH within dendrimer pockets. Protonation of the tertiary amine groups within PAMAM dendrimers plays an important role during this process. Interestingly, the absence of TEMPO-COOH encapsulation within carboxylate-terminated PAMAM dendrimer is observed due to the repulsion of TEMPO-COO- anion and anionic dendrimer surface. The combination of paramagnetic probes and ¹H NMR linewidth analysis can be used as a powerful tool in the analysis of dendrimer-based host-guest systems.

  7. Delivery of paclitaxel across cellular barriers using a dendrimer-based nanocarrier.

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    Teow, Huey Minn; Zhou, Zhengyuan; Najlah, Mohammad; Yusof, Siti R; Abbott, N Joan; D'Emanuele, Antony

    2013-01-30

    The aim of this study was to investigate the ability of a third-generation (G3) polyamidoamine (PAMAM) dendrimer-based carrier to enhance the permeability of paclitaxel (pac) and to overcome cellular barriers. G3 dendrimers were surface modified with lauryl chains (L) and conjugated with paclitaxel (pac) via a glutaric anhydride (glu) linker, followed by labeling with FITC. Biological evaluation of the dendrimer and conjugates was conducted using the human colon adenocarcinoma cell line (Caco-2) and primary cultured porcine brain endothelial cells (PBECs). LDH assay was used to evaluate the cytotoxicity of the dendrimer and conjugates. Cytotoxicity studies showed that the conjugation of lauryl chains and paclitaxel on G3 dendrimer significantly (pdendrimer-drug conjugates demonstrated an increase in the apparent permeability coefficient (P(app)) in both apical to basolateral A→B and basolateral to apical B→A directions across both cell monolayers compared to unmodified G3 and free drug. The B→A P(app) of paclitaxel was significantly (ptransporter system in both cell models. L6-G3-glu-pac conjugate had approximately 12-fold greater permeability across both cell monolayers than that of paclitaxel alone. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. Nanotherapeutics shielded with a pH responsive polymeric layer

    Czech Academy of Sciences Publication Activity Database

    Kostka, Libor; Šubr, Vladimír; Laga, Richard; Chytil, Petr; Ulbrich, Karel; Seymour, L. W.; Etrych, Tomáš

    2015-01-01

    Roč. 64, Suppl. 1 (2015), S29-S40 ISSN 0862-8408 R&D Projects: GA MŠk(CZ) EE2.3.30.0029; GA MŠk(CZ) ED1.1.00/02.0109; GA ČR(CZ) GAP301/12/1254 Institutional support: RVO:61389013 Keywords : nanotherapeutics * coating * pH responsive Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.643, year: 2015 http://www.biomed.cas.cz/physiolres/pdf/64%20Suppl%201/64_S29.pdf

  9. MRI

    DEFF Research Database (Denmark)

    Schroeter, Aileen; Rudin, Markus; Gianolio, Eliana

    2017-01-01

    This chapter discusses principles of nuclear magnetic resonance (NMR) and MRI followed by a survey on the major classes of MRI contrast agents (CA), their modes of action, and some of the most significative applications. The two more established classes of MRI-CA are represented by paramagnetic...... been attained that markedly increase the number and typology of systems with CEST properties. Currently much attention is also devoted to hyperpolarized molecules that display a sensitivity enhancement sufficient for their direct exploitation for the formation of the MR image. A real breakthrough...

  10. MRI

    Science.gov (United States)

    ... the room. Pins, hairpins, metal zippers, and similar metallic items can distort the images. Removable dental work ... an MRI can cause heart pacemakers and other implants not to work as well. The magnets can ...

  11. The nature and role of trap states in a dendrimer-based organic field-effect transistor explosive sensor

    Science.gov (United States)

    Tang, Guoqiang; Chen, Simon S. Y.; Lee, Kwan H.; Pivrikas, Almantas; Aljada, Muhsen; Burn, Paul L.; Meredith, Paul; Shaw, Paul E.

    2013-06-01

    We report the fabrication and charge transport characterization of carbazole dendrimer-based organic field-effect transistors (OFETs) for the sensing of explosive vapors. After exposure to para-nitrotoluene (pNT) vapor, the OFET channel carrier mobility decreases due to trapping induced by the absorbed pNT. The influence of trap states on transport in devices before and after exposure to pNT vapor has been determined using temperature-dependent measurements of the field-effect mobility. These data clearly show that the absorption of pNT vapor into the dendrimer active layer results in the formation of additional trap states. Such states inhibit charge transport by decreasing the density of conducting states.

  12. A new approach in the preparation of dendrimer-based bifunctional diethylenetriaminepentaacetic acid MR contrast agent derivatives.

    Science.gov (United States)

    Nwe, Kido; Xu, Heng; Regino, Celeste Aida S; Bernardo, Marcelino; Ileva, Lilia; Riffle, Lisa; Wong, Karen J; Brechbiel, Martin W

    2009-07-01

    In this paper, we report a new method to prepare and characterize a contrast agent based on a fourth-generation (G4) polyamidoamine (PAMAM) dendrimer conjugated to the gadolinium complex of the bifunctional diethylenetriamine pentaacetic acid derivative (1B4M-DTPA). The method involves preforming the metal-ligand chelate in alcohol prior to conjugation to the dendrimer. The dendrimer-based agent was purified by a Sephadex G-25 column and characterized by elemental analysis. The analysis and SE-HPLC data gave a chelate to dendrimer ratio of 30:1 suggesting conjugation at approximately every other amine terminal on the dendrimer. Molar relaxivity of the agent measured at pH 7.4 displayed a higher value than that of the analogous G4 dendrimer based agent prepared by the postmetal incorporation method (r(1) = 26.9 vs 13.9 mM(-1) s(-1) at 3 T and 22 degrees C). This is hypothesized to be due to the higher hydrophobicity of this conjugate and the lack of available charged carboxylate groups from noncomplexed free ligands that might coordinate to the metal and thus also reduce water exchange sites. Additionally, the distribution populations of compounds that result from the postmetal incorporation route are eliminated from the current product simplifying characterization as quality control issues pertaining to the production of such agents for clinical use as MR contrast agents. In vivo imaging in mice showed a reasonably fast clearance (t(1/2) = 24 min) suggesting a viable agent for use in clinical application.

  13. Multifunctional dendrimer-based nanoparticles for in vivo MR/CT dual-modal molecular imaging of breast cancer

    Directory of Open Access Journals (Sweden)

    Li K

    2013-07-01

    Full Text Available Kangan Li,1,4,5,* Shihui Wen,2,* Andrew C Larson,4,5 Mingwu Shen,2 Zhuoli Zhang,4,5 Qian Chen,3 Xiangyang Shi,2,3 Guixiang Zhang1 1Department of Radiology, Shanghai First People’s Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, People’s Republic of China; 2College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai, People’s Republic of China; 3State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Donghua University, Shanghai, People’s Republic of China; 4Departments of Radiology and Biomedical Engineering, Northwestern University, Chicago, IL, USA; 5Robert H Lurie Comprehensive Cancer Center, Chicago, IL, USA *These authors contributed equally to this work Abstract: Development of dual-mode or multi-mode imaging contrast agents is important for accurate and self-confirmatory diagnosis of cancer. We report a new multifunctional, dendrimer-based gold nanoparticle (AuNP as a dual-modality contrast agent for magnetic resonance (MR/computed tomography (CT imaging of breast cancer cells in vitro and in vivo. In this study, amine-terminated generation 5 poly(amidoamine dendrimers modified with gadolinium chelate (DOTA-NHS and polyethylene glycol monomethyl ether were used as templates to synthesize AuNPs, followed by Gd(III chelation and acetylation of the remaining dendrimer terminal amine groups; multifunctional dendrimer-entrapped AuNPs (Gd-Au DENPs were formed. The formed Gd-Au DENPs were used for both in vitro and in vivo MR/CT imaging of human MCF-7 cancer cells. Both MR and CT images demonstrate that MCF-7 cells and the xenograft tumor model can be effectively imaged. The Gd-Au DENPs uptake, mainly in the cell cytoplasm, was confirmed by transmission electron microscopy. The cell cytotoxicity assay, cell morphology observation, and flow cytometry show that the developed Gd-Au DENPs have good biocompatibility in the given concentration range. Our results

  14. A smart pH responsive graphene/polyacrylamide complex via noncovalent interaction

    International Nuclear Information System (INIS)

    Ren Lulu; Liu Tianxi; Guo Juan; Guo Shuzhong; Wang Xiaoyan; Wang Weizhi

    2010-01-01

    We report that the graphene sheets can be stably dispersed in water by hydrophobic interaction with polyacrylamide. Most interestingly, the resultant graphene-polyacrylamide complexes show a reversible pH responsive property although polyacrylamide itself does not possess such characteristics. This method opens up novel opportunities for the potential applications of graphene in intelligent sensors, biology, medicine, nanoelectronics and other relevant areas.

  15. Evaluation of liposomes coated with a pH responsive polymer

    OpenAIRE

    Barea, M.J.; Jenkins, M.J.; Gaber, M.H.; Bridson, R.H.

    2010-01-01

    Liposomes have been coated with the pH responsive polymer, Eudragit S100, and the formulation's potential for lower gastrointestinal (GI) targeting following oral administration assessed. Cationic liposomes were coated with the anionic polymer through simple mixing. The evolution of a polymer coat was studied using zeta potential measurements and laser diffraction size analysis. Further evidence of an association between polymer and liposome was obtained using light and cryo scanning electron...

  16. Encapsulation of Liposomes within pH Responsive Microspheres for Oral Colonic Drug Delivery

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    M. J. Barea

    2012-01-01

    Full Text Available A novel liposome-in-microsphere (LIM formulation has been created comprising drug-loaded liposomes within pH responsive Eudragit S100 microspheres. The liposomes contained the model drug 5-ASA and were coated with chitosan in order to protect them during encapsulation within the microspheres and to improve site-specific release characteristics. In vitro drug release studies showed that LIMs prevented drug release within simulated stomach and small intestine conditions with subsequent drug release occurring in large intestine conditions. The formulation therefore has potential for oral colonic drug delivery.

  17. Dendrimer-based selective autophagy-induction rescues ΔF508-CFTR and inhibits Pseudomonas aeruginosa infection in cystic fibrosis.

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    Scott Mackenzie Brockman

    Full Text Available Cystic Fibrosis (CF is a genetic disorder caused by mutation(s in the CF-transmembrane conductance regulator (Cftr gene. The most common mutation, ΔF508, leads to accumulation of defective-CFTR protein in aggresome-bodies. Additionally, Pseudomonas aeruginosa (Pa, a common CF pathogen, exacerbates obstructive CF lung pathology. In the present study, we aimed to develop and test a novel strategy to improve the bioavailability and potentially achieve targeted drug delivery of cysteamine, a potent autophagy-inducing drug with anti-bacterial properties, by developing a dendrimer (PAMAM-DEN-based cysteamine analogue.We first evaluated the effect of dendrimer-based cysteamine analogue (PAMAM-DENCYS on the intrinsic autophagy response in IB3-1 cells and observed a significant reduction in Ub-RFP and LC3-GFP co-localization (aggresome-bodies by PAMAM-DENCYS treatment as compared to plain dendrimer (PAMAM-DEN control. Next, we observed that PAMAM-DENCYS treatment shows a modest rescue of ΔF508-CFTR as the C-form. Moreover, immunofluorescence microscopy of HEK-293 cells transfected with ΔF508-CFTR-GFP showed that PAMAM-DENCYS is able to rescue the misfolded-ΔF508-CFTR from aggresome-bodies by inducing its trafficking to the plasma membrane. We further verified these results by flow cytometry and observed significant (p<0.05; PAMAM-DEN vs. PAMAM-DENCYS rescue of membrane-ΔF508-CFTR with PAMAM-DENCYS treatment using non-permeabilized IB3-1 cells immunostained for CFTR. Finally, we assessed the autophagy-mediated bacterial clearance potential of PAMAM-DENCYS by treating IB3-1 cells infected with PA01-GFP, and observed a significant (p<0.01; PAMAM-DEN vs. PAMAM-DENCYS decrease in intracellular bacterial counts by immunofluorescence microscopy and flow cytometry. Also, PAMAM-DENCYS treatment significantly inhibits the growth of PA01-GFP bacteria and demonstrates potent mucolytic properties.We demonstrate here the efficacy of dendrimer-based autophagy

  18. Study on Chitosan-Polyvinyl Alcohol Inter polymeric ph-Responsive Hydrogels for Controlled Drug Delivery

    International Nuclear Information System (INIS)

    Abdel-Bary, E.M.; El-Sherbiny, I.M.; Abdelaal, M.Y.; Abdel-Razik, E.A.

    2005-01-01

    Two series of ph-responsive biodegradable interpenetrating polymeric (IPN) hydrogels composed of chitosan and poly(vinyl alcohol) (PVA) were prepared for controlled drug release investigations. The first series was chemically crosslinked with different concentrations of glutaraldehyde as a crosslinked and the second series was crosslinked by gamma-radiation. Degree of crosslinking has been controlled by the concentration of crosslinked as well as by gamma irradiation dose. The equilibrium swelling -reflecting the degree of crosslinks - were carried out for the gels at 37 degree C in buffer solutions of ph 2.1 and 7.4 (simulated gastric and intestinal fluids respectively). 5-fluorouracil (5- FU) was entrapped, as a model therapeutic agent, in the hydrogels and equilibrium-swelling studies were carried out for the drug-entrapped gels at 37 degree C. The in-vitro release profiles of the drug were established at 37 degree C in ph 2.1 and 7.4. FT-IR was employed to investigate the structural changes of the gels with different degrees of crosslinking

  19. Ph responsive permeability and Ion- exchange characteristics of (PE/EPDM)-g-PMAA membranes

    International Nuclear Information System (INIS)

    El- Awady, M.M.; El-Awady, N.I.; Eissa, A.M.

    2005-01-01

    Chemical grafting of methacrylic acid (MAA) on low density exchange membranes for recovery of different cations from their solutions was investigated. When the dialysis permeability of two solutes (glucose + urea) through the membrane were tested at different ph values and compared, glucose was found to be less efficient than urea for permeation through the membrane. The permeability response of such solute was noticed only at higher ph value (ph 8). The grafted film (membrane) with graft yield of 185% is experimentally adequate to permeate all molecules with radius of lower than 4.3 x 10 polyethylene blended with EPDM with a ratio (90/10) films was carried out using sodium bisulphite as initiator. Factors affecting grafting and the properties of the grafted films were studied in details and showed improved hydrophilic properties, good thermal stability and nearly unaffected strength properties which make them acceptable for practical uses.In the present work, the possibility of practical uses of such grafted films as ph-responsive membranes in a dialysis process and as ion--7 mm. Grafted membranes in different forms (COOH-form), (Na-methacrylate form) and (K methacrylate- form) were prepared to evaluate the membranes uptake selectivity to different mono, di-and trivalent cations from their solutions. The results obtained showed very good efficiency of the prepared membranes as compared with the values obtained for the commercial cation exchange resin (Dowex)

  20. Novel pH responsive polymethacrylic acid-chitosan-polyethylene glycol nanoparticles for oral peptide delivery.

    Science.gov (United States)

    Sajeesh, S; Sharma, Chandra P

    2006-02-01

    In present study, novel pH sensitive polymethacrylic acid-chitosan-polyethylene glycol (PCP) nanoparticles were prepared under mild aqueous conditions via polyelectrolyte complexation. Free radical polymerization of methacrylic acid (MAA) was carried out in presence of chitosan (CS) and polyethylene glycol (PEG) using a water-soluble initiator and particles were obtained spontaneously during polymerization without using organic solvents or surfactants/steric stabilizers. Dried particles were analyzed by scanning electron microscopy (SEM) and particles dispersed in phosphate buffer (pH 7.0) were visualized under transmission electron microscope (TEM). SEM studies indicated that PCP particles have an aggregated and irregular morphology, however, TEM revealed that these aggregated particles were composed of smaller fragments with size less than 1 micron. Insulin and bovine serum albumin (BSA) as model proteins were incorporated into the nanoparticles by diffusion filling method and their in vitro release characteristics were evaluated at pH 1.2 and 7.4. PCP nanoparticles exhibited good protein encapsulation efficiency and pH responsive release profile was observed under in vitro conditions. Trypsin inhibitory effect of these PCP nanoparticles was studied using casein substrate and these particles displayed lesser inhibitory effect than reference polymer carbopol. Preliminary investigation suggests that these particles can serve as good candidate for oral peptide delivery. Copyright 2005 Wiley Periodicals, Inc.

  1. Rapid and quantitative detection of zoonotic influenza A virus infection utilizing coumarin-derived dendrimer-based fluorescent immunochromatographic strip test (FICT).

    Science.gov (United States)

    Yeo, Seon-Ju; Huong, Dinh Thi; Hong, Nguyen Ngoc; Li, Chun-Ying; Choi, Kyunghan; Yu, Kyoungsik; Choi, Du-Young; Chong, Chom-Kyu; Choi, Hak Soo; Mallik, Shyam Kumar; Kim, Hak Sung; Sung, Haan Woo; Park, Hyun

    2014-01-01

    Great efforts have been made to develop robust signal-generating fluorescence materials which will help in improving the rapid diagnostic test (RDT) in terms of sensitivity and quantification. In this study, we developed coumarin-derived dendrimer-based fluorescent immunochromatographic strip test (FICT) assay with enhanced sensitivity as a quantitative diagnostic tool in typical RDT environments. The accuracy of the proposed FICT was compared with that of dot blot immunoassay techniques and conventional RDTs. Through conjugation of coumarin-derived dendrimers with latex beads, fluorescent emission covering broad output spectral ranges was obtained which provided a distinct advantage of easy discrimination of the fluorescent emission of the latex beads with a simple insertion of a long-pass optical filter away from the excitation wavelength. The newly developed FICT assay was able to detect 100 ng/10 μL of influenza A nucleoprotein (NP) antigen within 5 minutes, which corresponded to 2.5-fold higher sensitivity than that of the dot blot immunoassay or conventional RDTs. Moreover, the FICT assay was confirmed to detect at least four avian influenza A subtypes (H5N3, H7N1, H7N7, and H9N2). On applying the FICT to the clinical swab samples infected with respiratory viruses, our FICT assay was confirmed to differentiate influenza H1N1 infection from other respiratory viral diseases. These data demonstrate that the proposed FICT assay is able to detect zoonotic influenza A viruses with a high sensitivity, and it enables the quantitation of the infection intensity by providing the numerical diagnostic values; thus demonstrating enhanced detectability of influenza A viruses.

  2. Heart MRI

    Science.gov (United States)

    Magnetic resonance imaging - cardiac; Magnetic resonance imaging - heart; Nuclear magnetic resonance - cardiac; NMR - cardiac; MRI of the heart; Cardiomyopathy - MRI; Heart failure - MRI; Congenital heart disease - MRI

  3. pH responsiveness of dendrimer-like poly(ethylene oxide)s.

    Science.gov (United States)

    Feng, Xiaoshuang; Taton, Daniel; Borsali, Redouane; Chaikof, Elliot L; Gnanou, Yves

    2006-09-06

    Poly(ethylene oxide) (PEO) and poly(acrylic acid) (PAA), two polymers known to form pH-sensitive aggregates through noncovalent interactions, were assembled in purposely designed architecture -a dendrimer-like PEO scaffold carrying short inner PAA chains-to produce unimolecular systems that exhibit pH responsiveness. Because of the particular placement of the PAA chains within the dendrimer-like structure, intermolecular complexation between acrylic acid (AA) and ethylene oxide (EO) units-and thus macroscopic aggregation or even mesoscopic micellization-could be avoided in favor of the sole intramolecular complexation. The sensitivity of such interactions to pH was exploited to generate dendrimer-like PEOs that reversibly shrink and expand with the pH. Such PAA-carrying dendrimer-like PEOs were synthesized in two main steps. First, a fifth-generation dendrimer-like PEO was obtained by combining anionic ring-opening polymerization (AROP) of ethylene oxide from a tris-hydroxylated core and selective branching reactions of PEO chain ends. To this end, an AB(2)C-type branching agent was designed: the latter includes a chloromethyl (A) group for its covalent attachment to the arm ends, two geminal hydroxyls (B(2)) protected in the form of a ketal ring for the growth of subsequent PEO generations by AROP, and a vinylic (C) double bonds for further functionalization of the interior of dendrimer-like PEOs. Reiteration of AROP and derivatization of PEO branches allowed us to prepare a dendrimer-like PEO of fourth generation with a total molar mass of 52,000 g x mol(-1), containing 24 external hydroxyl functions and 21 inner vinylic groups in the interior. A fifth generation of PEO chains was generated from this parent dendrimer-like PEO of fourth generation using a "conventional" AB(2)-type branching agent, and 48 PEO branches could be grown by AROP. The 48 outer hydroxy-end groups of the fifth-generation dendrimer-like PEO obtained were subsequently quantitatively converted into inert benzylic groups using benzyl bromide. The 21 internal vinylic groups carried by the PEO scaffold were then chemically modified in a two-step sequence into bromoester groups. The latter which are atom transfer radical polymerization (ATRP) initiating sites thus served to grow poly(tert-butylacrylate) chains. After a final step of hydrolysis of the tert-butyl ester groups, double, hydrophilic, dendrimer-like PEOs comprising 21 internal junction-attached poly(acrylic acid) (PAA) blocks could be obtained. Dynamic light scattering was used to determine the size of these dendrimer-like species in water and to investigate their response to pH variation: in particular, how the pH-sensitive complexation of EO and AA units affects their overall behavior.

  4. A novel thermal and pH responsive drug delivery system based on ZnO@PNIPAM hybrid nanoparticles

    International Nuclear Information System (INIS)

    Tan, Licheng; Liu, Jian; Zhou, Weihua; Wei, Junchao; Peng, Zhiping

    2014-01-01

    A smart ZnO@PNIPAM hybrid was prepared by grafting thermal responsive poly(N-isopropylacrylamide) (PNIPAM) on zinc oxide (ZnO) nanoparticles via surface-initiated atom transfer radical polymerization (ATRP). The thermal gravimetric analysis (TGA) shows that the grafting amount of PNIPAM was about 38%, and the SEM images show that the PNIPAM chains can prevent the aggregation of ZnO nanoparticles. The responsive properties of ZnO@PNIPAM were measured by photoluminescence spectra, and the results demonstrate that the PNIPAM chains grafted on ZnO surfaces can realize reversible thermal responsive and photoluminescence properties. An anticancer drug, doxorubicin (Dox), was used as a model drug and loaded into the hybrid nanoparticles, and an in vitro drug release test implied that ZnO@PNIPAM could work as a thermal responsive drug delivery system. Furthermore, pH sensitive drug releases were carried out in acetate buffer at pH 5.0 and pH 6.0 and in water at pH 7.0, and the results showed evident pH dependency, showing its pH responsive properties. - Graphical abstract: In this manuscript, thermal responsive poly(N-isopropylacrylamide) (PNIPAM) was grafted on the surface of ZnO nanoparticles. The obtained ZnO@PNIPAM hybrid showed reversible thermal responsive photoluminescent properties, and can also work as a thermal and pH responsive drug delivery system. - Highlights: • The ZnO@PNIPAM hybrid was prepared via ATRP. • The ZnO@PNIPAM hybrid showed thermal responsive properties. • The ZnO@PNIPAM hybrid can work as a thermal and pH responsive drug delivery system

  5. Titanophosphate glasses as lithium-free nonsilicate pH-responsive glasses—Compatibility between pH responsivity and self-cleaning properties

    International Nuclear Information System (INIS)

    Hashimoto, Tadanori; Wagu, Moe; Kimura, Kentaro; Nasu, Hiroyuki; Ishihara, Atsushi; Nishio, Yuji; Iwamoto, Yasukazu

    2012-01-01

    Highlights: ► Ti 3+ -containing TP glasses are lithium-free nonsilicate pH-responsive ones. ► TP glasses with a large amount of Ti 3+ ions show good pH responsivity. ► TP glasses with pH responsivity and self-cleaning properties are obtained. ► pH response of TP glasses is explained by phase boundary potential model. -- Abstract: Lithium silicate-based glasses have been widely used as commercially available pH glass electrodes. It was revealed that Ti 3+ -containing titanophosphate (TiO 2 –P 2 O 5 , TP) glasses are pH-responsive as lithium-free nonsilicate glasses for the first time. The absorption coefficient at 532 nm, α 532 as a measure of Ti 3+ content in TP glasses increased with increasing melting temperature. TP glasses with large α 532 tended to give low electrical resistivity, high pH sensitivity and the short pH response time. The first post-annealing (oxidation of Ti 3+ ) of TP glasses at 600–620 °C for 60–240 h resulted in the occurrence of the photo-induced hydrophilicity along with the disappearance of pH responsivity and the increase of electrical resistivity. The second post-annealing (reduction of Ti 4+ ) of the first post-annealed TP glasses at 600–620 °C for 48 h under vacuum recovered both pH responsivity and electrical resistivity to the level of the as-prepared TP glasses with maintaining the photo-induced hydrophilicity. Moreover, the second post-annealed TP glasses had photocatalytic activity for methylene blue (MB) comparable to commercially available self-cleaning glass. Thus, TP glasses with the compatibility between pH responsivity and self-cleaning properties were obtained by the sequential post-annealing (oxidation and reduction) of as-prepared glasses. From some circumstantial evidences, pH response of TP glasses was explained in terms of phase boundary potential model related to hopping conduction of electron from Ti 3+ to Ti 4+ via O 2− ion in TP glasses rather than diffusion potential model.

  6. Molecular layer deposition of APTES on silicon nanowire biosensors: Surface characterization, stability and pH response

    International Nuclear Information System (INIS)

    Liang, Yuchen; Huang, Jie; Zang, Pengyuan; Kim, Jiyoung; Hu, Walter

    2014-01-01

    Graphical abstract: - Abstract: We report the use of molecular layer deposition (MLD) for depositing 3-aminopropyltriethoxysilane (APTES) on a silicon dioxide surface. The APTES monolayer was characterized using spectroscopic ellipsometry, contact angle goniometry, and atomic force microscopy. Effects of reaction time of repeating pulses and simultaneous feeding of water vapor with APTES were tested. The results indicate that the synergistic effects of water vapor and reaction time are significant for the formation of a stable monolayer. Additionally, increasing the number of repeating pulses improved the APTES surface coverage but led to saturation after 10 pulses. In comparing MLD with solution-phase deposition, the APTES surface coverage and the surface quality were nearly equivalent. The hydrolytic stability of the resulting films was also studied. The results confirmed that the hydrolysis process was necessary for MLD to obtain stable surface chemistry. Furthermore, we compared the pH sensing results of Si nanowire field effect transistors (Si NWFETs) modified by both the MLD and solution methods. The highly repeatable pH sensing results reflected the stability of APTES monolayers. The results also showed an improved pH response of the sensor prepared by MLD compared to the one prepared by the solution treatment, which indicated higher surface coverage of APTES

  7. Improving the in vivo therapeutic index of siRNA polymer conjugates through increasing pH responsiveness.

    Science.gov (United States)

    Guidry, Erin N; Farand, Julie; Soheili, Arash; Parish, Craig A; Kevin, Nancy J; Pipik, Brenda; Calati, Kathleen B; Ikemoto, Nori; Waldman, Jacob H; Latham, Andrew H; Howell, Bonnie J; Leone, Anthony; Garbaccio, Robert M; Barrett, Stephanie E; Parmar, Rubina Giare; Truong, Quang T; Mao, Bing; Davies, Ian W; Colletti, Steven L; Sepp-Lorenzino, Laura

    2014-02-19

    Polymer based carriers that aid in endosomal escape have proven to be efficacious siRNA delivery agents in vitro and in vivo; however, most suffer from cytotoxicity due in part to a lack of selectivity for endosomal versus cell membrane lysis. For polymer based carriers to move beyond the laboratory and into the clinic, it is critical to find carriers that are not only efficacious, but also have margins that are clinically relevant. In this paper we report three distinct categories of polymer conjugates that improve the selectivity of endosomal membrane lysis by relying on the change in pH associated with endosomal trafficking, including incorporation of low pKa heterocycles, acid cleavable amino side chains, or carboxylic acid pH sensitive charge switches. Additionally, we determine the therapeutic index of our polymer conjugates in vivo and demonstrate that the incorporation of pH responsive elements dramatically expands the therapeutic index to 10-15, beyond that of the therapeutic index (less than 3), for polymer conjugates previously reported.

  8. Molecular layer deposition of APTES on silicon nanowire biosensors: Surface characterization, stability and pH response

    Science.gov (United States)

    Liang, Yuchen; Huang, Jie; Zang, Pengyuan; Kim, Jiyoung; Hu, Walter

    2014-12-01

    We report the use of molecular layer deposition (MLD) for depositing 3-aminopropyltriethoxysilane (APTES) on a silicon dioxide surface. The APTES monolayer was characterized using spectroscopic ellipsometry, contact angle goniometry, and atomic force microscopy. Effects of reaction time of repeating pulses and simultaneous feeding of water vapor with APTES were tested. The results indicate that the synergistic effects of water vapor and reaction time are significant for the formation of a stable monolayer. Additionally, increasing the number of repeating pulses improved the APTES surface coverage but led to saturation after 10 pulses. In comparing MLD with solution-phase deposition, the APTES surface coverage and the surface quality were nearly equivalent. The hydrolytic stability of the resulting films was also studied. The results confirmed that the hydrolysis process was necessary for MLD to obtain stable surface chemistry. Furthermore, we compared the pH sensing results of Si nanowire field effect transistors (Si NWFETs) modified by both the MLD and solution methods. The highly repeatable pH sensing results reflected the stability of APTES monolayers. The results also showed an improved pH response of the sensor prepared by MLD compared to the one prepared by the solution treatment, which indicated higher surface coverage of APTES.

  9. Redox and pH Responsive Poly (Amidoamine Dendrimer-Heparin Conjugates via Disulfide Linkages for Letrozole Delivery

    Directory of Open Access Journals (Sweden)

    Thanh Luan Nguyen

    2017-01-01

    Full Text Available Heparin (Hep conjugated to poly (amidoamine dendrimer G3.5 (P via redox-sensitive disulfide bond (P-SS-Hep was studied. The redox and pH dual-responsive nanocarriers were prepared by a simple method that minimized many complex steps as previous studies. The functional characterization of G3.5 coated Hep was investigated by the proton nuclear magnetic resonance spectroscopy. The size and formation were characterized by the dynamic light scattering, zeta potential, and transmission electron microscopy. P-SS-Hep was spherical in shape with average diameter about 11 nm loaded with more than 20% letrozole. This drug carrier could not only eliminate toxicity to cells and improve the drugs solubility but also increase biocompatibility of the system under reductive environment of glutathione. In particular, P-SS-Hep could enhance the effectiveness of cancer therapy after removing Hep from the surface. These results demonstrated that the P-SS-Hep conjugates could be a promising candidate as redox and pH responsive nanocarriers for cancer chemotherapy.

  10. Genipin Cross-Linked Chitosan-Polyvinylpyrrolidone Hydrogels: Influence of Composition and Postsynthesis Treatment on pH Responsive Behaviour

    Directory of Open Access Journals (Sweden)

    Chinyelumndu Jennifer Nwosu

    2015-01-01

    Full Text Available Understanding the factors that influence the pH responsive behaviour of biocompatible cross-linked hydrogel networks is essential when aiming to synthesise a mechanically stable and yet stimuli responsive material suitable for various applications including drug delivery and tissue engineering. In this study the behaviour of intelligent chitosan-polyvinylpyrrolidone-genipin cross-linked hydrogels is examined as a function of their composition and postsynthesis treatment. Hydrogels are synthesised with varying amounts of each component (chitosan, polyvinylpyrrolidone, and genipin and their response in a pH 2 buffer is measured optically. The influence of postsynthesis treatment on stability and smart characteristics is assessed using selected hydrogel samples synthesised at 30, 40, and 50°C. After synthesis, samples are exposed to either continuous freezing or three freeze-thaw cycles resulting in increased mechanical stability for all samples. Further morphological and mechanical characterisations have aided the understanding of how postsynthesis continual freezing or freeze-thaw manipulation affects network attributes.

  11. Influence of polymer network parameters of tragacanth gum-based pH responsive hydrogels on drug delivery.

    Science.gov (United States)

    Singh, Baljit; Sharma, Vikrant

    2014-01-30

    The present article deals with design of tragacanth gum-based pH responsive hydrogel drug delivery systems. The characterization of hydrogels has been carried out by SEMs, EDAX, FTIR, (13)C NMR, XRD, TGA/DTA/DTG and swelling studies. The correlation between reaction conditions and structural parameters of polymer networks such as polymer volume fraction in the swollen state (ϕ), Flory-Huggins interaction parameter (χ), molecular weight of the polymer chain between two neighboring cross links (M¯c), crosslink density (ρ) and mesh size (ξ) has been determined. The different kinetic models such as zero order, first order, Higuchi square root law, Korsmeyer-Peppas model and Hixson-Crowell cube root model were applied and it has been observed that release profile of amoxicillin best followed the first order model for the release of drug from the polymer matrix. The swelling of the hydrogels and release of drug from the drug loaded hydrogels occurred through non-Fickian diffusion mechanism in pH 7.4 solution. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Investigation of pH response and photo-control of wettability on spiropyran-derivatized surfaces

    Science.gov (United States)

    Park, Choong-Do

    2009-12-01

    One promising method to control a liquid drop on a surface for microfluidic devices is to use the surface tension gradient on a photo-responsive surface by light irradiation. A photo-switchable spiropyran monolayer was prepared on smooth glass or silicon wafers via 3-aminopropylmethyldiethoxysilane linkages. The pH response of the surface-bound spiropyran was investigated by measuring contact angle as a function of pH, since the pH value of the liquids applied to a microfluidic system can vary widely. Based on the contact angle titration and UV-Vis spectroscopic data, a protonation and deprotonation mechanism of the surface-bound spiropyran was proposed. The advancing contact angles under UV and under visible light irradiation at high pH values were about 100 smaller than those at low pH values. The decrease in contact angle under UV light with decreasing pH value was assigned to the protonation of open merocyanine (MC) to MC-OH+. Meanwhile, the decrease in contact angle under visible light was attributed to the protonation of the closed spiropryan (SP), generating a mixed state of MC-OH+ in equilibrium with N-protonated SP-NH+. In order to examine the possibility of light-induced liquid drop motion on the spiropyran-derivatized smooth surfaces, the light-induced surface tension change between SP and MC was estimated using the contact angle hysteresis (CAH) and the Lifshitz---van der Waals/Acid-Base (LWAB) approaches based on the contact angle data. The average light-induced surface energy change between the two isomers under UV and visible light exposure was 1.4 mJ/m 2, implying that the small change in surface tension is not sufficient to move a liquid droplet on the surface. Liquid drop motion requires that the light-induced switching angle be greater than the contact angle hysteresis. However, the light-induced switching angle of the spiropyran-derivatized surface was significantly smaller than the hysteresis. Thus, in order to achieve liquid drop motion on the spiropyran-derivatized surface, a new surface design which employs a combination of chemical modification of a hydrophobic organosilane and micropatterned rough surface morphology was suggested.

  13. Chest MRI

    Science.gov (United States)

    ... resonance imaging - chest; NMR - chest; MRI of the thorax; Thoracic MRI Patient Instructions ... Gotway MB, Panse PM, Gruden JF, Elicker BM. Thoracic radiology. In: Broaddus VC, Mason RJ, Ernst JD, et ...

  14. Chitosan capped nanoscale Fe-MIL-88B-NH2 metal-organic framework as drug carrier material for the pH responsive delivery of doxorubicin

    Science.gov (United States)

    Sivakumar, P.; Priyatharshni, S.; Nagashanmugam, K. B.; Thanigaivelan, A.; Kumar, K.

    2017-08-01

    In recent years nanoscale metal-organic frameworks (NMOFs) are contributing as an effective material for use in drug delivery and imaging applications due to their porous surfaces and easy surface modifications. In this work, Fe-MIL-88B-NH2 NMOFs were successfully synthesized on facile hydrothermal route and 2-aminoterephthalic acid (NH2-BDC) was employed as a bridging ligand to activate amine functional groups on the surface. Amine functional groups not only serve as a structure stabilizing agent but also enhance the loading efficiency of the doxorubicin (DOX) anticancer drug. A pH responsive DOX release was realized by introducing a positively charged chitosan (Chi) capping layer. Upon Chi-coating, cleavage was observed in the Fe-MIL-88B-NH2 structure at acidic pH, while gel-like insoluble structure was formed at basic pH. By utilizing this phenomenon, a pH responsive DOX release system was developed by using Chi capped Fe-MIL-88B-NH2 NMOFs under the designed pH (4.0-8.0). The results suggest the Chi capped Fe-MIL-88B-NH2 can be a promising candidate for future pH responsive drug delivery systems.

  15. Induction of a robust immune response against avian influenza virus following transdermal inoculation with H5-DNA vaccine formulated in modified dendrimer-based delivery system in mouse model.

    Science.gov (United States)

    Bahadoran, Azadeh; Ebrahimi, Mehdi; Yeap, Swee Keong; Safi, Nikoo; Moeini, Hassan; Hair-Bejo, Mohd; Hussein, Mohd Zobir; Omar, Abdul Rahman

    2017-01-01

    This study was aimed to evaluate the immunogenicity of recombinant plasmid deoxyribonucleic acid (DNA), pBud-H5-green fluorescent protein (GFP)-interferon-regulatory factor (IRF)3 following delivery using polyamidoamine (PAMAM) dendrimer and transactivator of transcription (TAT)-conjugated PAMAM dendrimer as well as the effect of IRF3 as the genetic adjuvant. BALB/c mice were vaccinated transdermally with pBud-H5-GFP, PAMAM/pBud-H5-GFP, TAT-PAMAM/pBud-H5-GFP, and TAT-PAMAM/pBud-H5-GFP-IRF3. The expression analysis of H5 gene from the blood by using quantitative real-time reverse transcriptase polymerase chain reaction confirmed the ability of PAMAM dendrimer as a carrier for gene delivery, as well as the ability of TAT peptide to enhance the delivery efficiency of PAMAM dendrimer. Mice immunized with modified PAMAM by TAT peptide showed higher hemagglutination inhibition titer, and larger CD3 + /CD4 + T cells and CD3 + /CD8 + T cells population, as well as the production of cytokines, namely, interferon (IFN)-γ, interleukin (IL)-2, IL-15, IL-12, IL-6, and tumor necrosis factor-α compared with those immunized with native PAMAM. These results suggest that the function of TAT peptide as a cell-penetrating peptide is able to enhance the gene delivery, which results in rapid distribution of H5 in the tissues of the immunized mice. Furthermore, pBud-H5-GFP co-expressing IRF3 as a genetic adjuvant demonstrated the highest hemagglutination inhibition titer besides larger CD3 + /CD4 + and CD3 + /CD8 + T cells population, and strong Th1-like cytokine responses among all the systems tested. In conclusion, TAT-PAMAM dendrimer-based delivery system with IRF3 as a genetic adjuvant is an attractive transdermal DNA vaccine delivery system utilized to evaluate the efficacy of the developed DNA vaccine in inducing protection during challenge with virulent H5N1 virus.

  16. The effect of distribution of monomer moiety on the pH response and mechanical properties of poly(acrylonitrile-co-acrylic acid) copolymers

    International Nuclear Information System (INIS)

    Sahoo, Anasuya; Jassal, Manjeet; Agrawal, Ashwini K

    2010-01-01

    The pH response and mechanical properties of copolymer-based hydrogels such as poly(acrylonitrile-co-acrylic acid) are usually attributed to their chemical composition. In this study, it has been shown that the architecture of the polymer chains, i.e. the distribution of comonomers in the macromolecules, also plays a major role in controlling these properties. A series of four poly(acrylonitrile-co-acrylic acids) with fixed composition (i.e. ∼30 mol% acrylic acid moieties) were synthesized, where the block lengths of both AN (acrylonitrile) and AAc (acrylic acid) moieties in the copolymers were varied by controlling the feeding pattern of the monomers during free radical copolymerization. These copolymers were then converted into fine fibers of the same dimensions. The monomer distribution in the four copolymers was estimated using quantitative carbon 13 C nuclear magnetic resonance (NMR) and related to the mechanical and pH response properties of the resultant fibers. The pH response of the fibers with similar composition increased dramatically as the block length of the AAc moiety was increased, while the mechanical properties increased as a direct function of the block length of the AN moieties. The fiber's response at pH 10 in terms of the change in length increased by ∼four times while its response rate increased by ∼50 times with the increase in block length of the AAc moiety. On the other hand, the tensile properties and retractive stress increased by ∼four times with the increase in the block length of the AN moiety

  17. The effect of distribution of monomer moiety on the pH response and mechanical properties of poly(acrylonitrile-co-acrylic acid) copolymers

    Science.gov (United States)

    Sahoo, Anasuya; Jassal, Manjeet; Agrawal, Ashwini K.

    2010-02-01

    The pH response and mechanical properties of copolymer-based hydrogels such as poly(acrylonitrile-co-acrylic acid) are usually attributed to their chemical composition. In this study, it has been shown that the architecture of the polymer chains, i.e. the distribution of comonomers in the macromolecules, also plays a major role in controlling these properties. A series of four poly(acrylonitrile-co-acrylic acids) with fixed composition (i.e. ~30 mol% acrylic acid moieties) were synthesized, where the block lengths of both AN (acrylonitrile) and AAc (acrylic acid) moieties in the copolymers were varied by controlling the feeding pattern of the monomers during free radical copolymerization. These copolymers were then converted into fine fibers of the same dimensions. The monomer distribution in the four copolymers was estimated using quantitative carbon 13C nuclear magnetic resonance (NMR) and related to the mechanical and pH response properties of the resultant fibers. The pH response of the fibers with similar composition increased dramatically as the block length of the AAc moiety was increased, while the mechanical properties increased as a direct function of the block length of the AN moieties. The fiber's response at pH 10 in terms of the change in length increased by ~four times while its response rate increased by ~50 times with the increase in block length of the AAc moiety. On the other hand, the tensile properties and retractive stress increased by ~four times with the increase in the block length of the AN moiety.

  18. Generation of pH responsive fluorescent nano capsules through simple steps for the oral delivery of low pH susceptible drugs

    Science.gov (United States)

    Radhakumary, Changerath; Sreenivasan, Kunnatheeri

    2016-11-01

    pH responsive nano capsules are promising as it can encapsulate low pH susceptible drugs like insulin and guard them from the hostile environments in the intestinal tract. The strong acidity of the gastro-intestinal tract and the presence of proteolytic enzymes are the tumbling blocks for the design of drug delivery vehicles through oral route for drugs like insulin. Nano capsules are normally built over templates which are subsequently removed by further steps. Such processes are complex and often lead into deformed and collapsed capsules. In this study, we choose calcium carbonate (CaCO3) nano particles to serve as template. Over CaCO3 nanoparticles, silica layers were built followed by polymethacrylic acid chains to acquire pH responsiveness. During the polymerization process of the methacrylic acid, the calcium carbonate core particles were dissolved leading to the formation of nano hollow capsules having a size that ranges from 225 to 246 nm and thickness from 19 to 58 nm. The methodology is simple and devoid of additional steps. The nano shells exhibited 80% release of the loaded model drug, insulin at pH 7.4 while at pH 2.0 the capsules nearly stopped the release of the drug. Polymethacrylic acid shows pH responsive swelling behavior that it swells at intestinal pH (7.0-7.5) and shrinks at gastric pH (˜2.0) thus enabling the safe unloading of the drug from the nano capsules.

  19. Dendrimer-based dynamic combinatorial libraries

    NARCIS (Netherlands)

    Chang, T.; Meijer, E.W.

    2005-01-01

    The aim of this project is to create water-sol. dynamic combinatorial libraries based upon dendrimer-guest complexes. The guest mols. are designed to bind to dendrimers using multiple secondary interactions, such as electrostatics and hydrogen bonding. We have been able to incorporate various guest

  20. MRI Primer

    International Nuclear Information System (INIS)

    Oldendorf, W.; Oldendorf, W. Jr.

    1991-01-01

    Designed for studies, radiologists, and clinicians at all levels of training, this book provides a basic introduction to the principles, physics, and instrumentation of magnetic resonance imaging. The fundamental concepts that are essential for the optimal clinical use of MRI are thoroughly explained in easily accessible terms. To facilitate the reader's comprehension, the material is presented nonmathematically, using no equations and a minimum of symbols and abbreviations. MRI Primer presents a clear account of the phenomenon of nuclear magnetic resonance and the use of gradient magnetic fields to create clinically useful images of cross-sectional slices. Close attention is given to the magnetization vector as a means of expressing nuclear behavior, the role of T 1 and T 2 weighing in imaging, the use of contrast agents, and the pulse sequences most often used in clinical practice, as well as to the relative capabilities and limitations of MRI and CT. The basic hardware components of an MRI scanner are described in detail. Sample MRI scans illustrate how MRI characterizes tissue. An appendix provides a brief introduction to quantum processes in MRI

  1. Investigation of a potential macromolecular MRI contrast agent prepared from PPI (G = 2, polypropyleneimine, generation 2) dendrimer bifunctional chelates

    Science.gov (United States)

    Wang, Jianxin Steven

    The long-term objective is to develop magnetic resonance (MR) contrast agents that actively and passively target tumors for diagnosis and therapy. Many diagnostic imaging techniques for cancer lack specificity. A dendrimer based magnetic resonance imaging contrast agent has been developed with large proton relaxation enhancements and high molecular relaxivities. A new type of linear dendrimer based MRI contrast agent that is built from the polypropyleneimine and polyamidoamine dendrimers in which free amines have been conjugated to the chelate DTPA, which further formed the complex with Gadolinium (Gd) was studied. The specific research goals were to test the hypothesis that a linear chelate with macromolecular agents can be used in vitro and in vivo. This work successfully examined the adequacy and viability of the application for this agent in vitro and in vivo. A small animal whole body counter was designed and constructed to allow us to monitor biodistribution and kinetic mechanisms using a radioisotope labeled complex. The procedures of metal labeling, separation and purification have been established from this work. A biodistribution study has been performed using radioisotope induced organ/tissue counting and gamma camera imaging. The ratio of percentage of injected dose per gram organ/tissue for kidney and liver is 3.71 from whole body counter and 3.77 from the gamma camera. The results suggested that retention of Gd (III) is too high and a more kinetically stable chelate should be developed. The pharmacokinetic was evaluated in the whole animal model with the whole body clearance, and a kinetics model was developed. The pharmacokinetic results showed a bi-exponential decay in the animal model with two component excretion constants 1.43e(-5) and 0.0038511, which give half-lives of 3 hours and 33.6 days, respectively. Magnetic resonance imaging of this complex resulted in a 52% contrast enhancement in the rat kidney following the agents' administration in

  2. Head MRI

    Science.gov (United States)

    ... hearing aids Pins, hairpins, metal zippers, and similar metallic items Removable dental work How the Test will ... an MRI can make heart pacemakers and other implants not work as well. It can also cause ...

  3. Pediatric MRI

    Data.gov (United States)

    U.S. Department of Health & Human Services — The NIH Study of Normal Brain Development is a longitudinal study using anatomical MRI, diffusion tensor imaging (DTI), and MR spectroscopy (MRS) to map pediatric...

  4. Comparison of MRI properties between derivatized DTPA and DOTA gadolinium-dendrimer conjugates.

    Science.gov (United States)

    Nwe, K; Bernardo, M; Regino, C A S; Williams, M; Brechbiel, M W

    2010-08-15

    In this report we directly compare the in vivo and in vitro MRI properties of gadolinium-dendrimer conjugates of derivatized acyclic diethylenetriamine-N,N',N',N'',N''-pentaacetic acid (1B4M-DTPA) and macrocyclic 1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid (C-DOTA). The metal-ligand chelates were pre-formed in alcohol prior to conjugation to the generation 4 PAMAM dendrimer (G4D), and the dendrimer-based agents were purified by Sephadex(R) G-25 column. The analysis and SE-HPLC data indicated chelate to dendrimer ratios of 30:1 and 28:1, respectively. Molar relaxivity measured at pH 7.4, 22 degrees C, and 3T are comparable (29.5 vs 26.9 mM(-1)s(-1)), and both conjugates are equally viable as MRI contrast agents based on the images obtained. The macrocyclic agent however exhibits a faster rate of clearance in vivo (t(1/2)=16 vs 29 min). Our conclusion is that the macrocyclic-based agent is the more suitable agent for in vivo use for these reasons combined with kinetic inertness associated with the Gd(III) DOTA complex stability properties. Published by Elsevier Ltd.

  5. pH responsive label-assisted click chemistry triggered sensitivity amplification for ultrasensitive electrochemical detection of carbohydrate antigen 24-2.

    Science.gov (United States)

    Zheng, Yun; Zhao, Lihua; Ma, Zhanfang

    2018-05-15

    Sensitivity amplification strategy by implementing click chemistry in the construction of biosensing interface can efficiently improve the performance of immunosensor. Herein, we developed a sandwich-type amperometric immunosensor for ultrasensitive detection of carbohydrate antigen 24-2 (CA 242) based on pH responsive label-assisted click chemistry triggered sensitivity amplification strategy. The sensitivity of amperometric immunosensor relies on the current response differences (ΔI) caused by per unit concentration target analyte. The pH responsive Cu 2+ -loaded polydopamine (CuPDA) particles conjugated with detection antibodies were employed as labels, which can release Cu(II) ions by regulating pH. In the presence of ascorbic acid (reductant), Cu(II) ions were reduced to Cu(I) ions. Azide-functionalized double-stranded DNA (dsDNA) as signal enhancer was immobilized on the substrate through Cu + -catalyzed azide/alkyne cycloaddition reaction. With the help of the click reaction, the ΔI caused by target was elevated prominently, resulting in sensitivity amplification of the immunosensor. Under optimal condition, the proposed immunosensor exhibited excellent performance with linear range from 0.0001 to 100 U mL -1 and ultralow detection limit of 20.74 μU mL -1 . This work successfully combines click chemistry with pH-responsive labels in sandwich-type amperometric immunosensor, providing a promising sensitivity amplification strategy to construct immunosensing platform for analysis of other tumor marker. Copyright © 2018 Elsevier B.V. All rights reserved.

  6. Portable MRI

    Energy Technology Data Exchange (ETDEWEB)

    Espy, Michelle A. [Los Alamos National Laboratory

    2012-06-29

    This project proposes to: (1) provide the power of MRI to situations where it presently isn't available; (2) perform the engineering required to move from lab to a functional prototype; and (3) leverage significant existing infrastructure and capability in ultra-low field MRI. The reasons for doing this: (1) MRI is the most powerful tool for imaging soft-tissue (e.g. brain); (2) Billions don't have access due to cost or safety issues; (3) metal will heat/move in high magnetic fields; (4) Millions of cases of traumatic brain injury in US alone; (5) even more of non-traumatic brain injury; (6) (e.g. stroke, infection, chemical exposure); (7) Need for early diagnostic; (8) 'Signature' wound of recent conflicts; (9) 22% of injuries; (10) Implications for post-traumatic stress disorder; and (11) chronic traumatic encephalopathy.

  7. Portable MRI

    International Nuclear Information System (INIS)

    Espy, Michelle A.

    2012-01-01

    This project proposes to: (1) provide the power of MRI to situations where it presently isn't available; (2) perform the engineering required to move from lab to a functional prototype; and (3) leverage significant existing infrastructure and capability in ultra-low field MRI. The reasons for doing this: (1) MRI is the most powerful tool for imaging soft-tissue (e.g. brain); (2) Billions don't have access due to cost or safety issues; (3) metal will heat/move in high magnetic fields; (4) Millions of cases of traumatic brain injury in US alone; (5) even more of non-traumatic brain injury; (6) (e.g. stroke, infection, chemical exposure); (7) Need for early diagnostic; (8) 'Signature' wound of recent conflicts; (9) 22% of injuries; (10) Implications for post-traumatic stress disorder; and (11) chronic traumatic encephalopathy.

  8. Fetal MRI

    International Nuclear Information System (INIS)

    Prayer, D.; Brugger, P.C.

    2004-01-01

    New, ultrafast sequences have made it possible to obtain MR images of the fetus without maternal sedation or immobilization of the fetus itself. While fetal MRI began as an adjunct to ultrasound, it has now been shown that MRI can provide additional information that may change prognosis, the management of pregnancy, or the treatment of the newborn child. It is of particular value in the assessment of malformations of the central nervous system. The steady development and adaptation of MR-sequences to the needs of fetal imaging has led to new indications that can support prognostic and therapeutic decisions. (orig.)

  9. Interventional MRI

    Energy Technology Data Exchange (ETDEWEB)

    Harada, Junta; Dohi, Michiko; Yoshihiro, Akiko; Mogami, Takuji; Kuwada, Tomoko; Nakata, Norio [Jikei Univ., Chiba (Japan). Kashiwa Hospital

    2000-06-01

    Open type MR system and fast sequence is now available and MRI becomes a new modality for interventional Radiology, including biopsy, drainage operation, and monitoring for minimally invasive therapy. Experimental studies of temperature monitoring were performed under hot and cold status. Signal changes of porcine disc and meat under microwave and laser ablation were observed as low signal area by signal intensity method. Using proton chemical shift method, signal change by laser ablation was displaced color imaging and correlated with thermometric temperature measurement. The very T2 relaxation time of ice affords excellent contrast between ice and surrounding gelatin tissue allowing acute depiction of the extent of the iceball under MRI. (author)

  10. Fetal MRI

    Energy Technology Data Exchange (ETDEWEB)

    Prayer, D.; Brugger, P.C. [University Hospital of Vienna (Austria). Division of Neuroradiology

    2004-07-01

    New, ultrafast sequences have made it possible to obtain MR images of the fetus without maternal sedation or immobilization of the fetus itself. While fetal MRI began as an adjunct to ultrasound, it has now been shown that MRI can provide additional information that may change prognosis, the management of pregnancy, or the treatment of the newborn child. It is of particular value in the assessment of malformations of the central nervous system. The steady development and adaptation of MR-sequences to the needs of fetal imaging has led to new indications that can support prognostic and therapeutic decisions. (orig.)

  11. MRI angiography

    International Nuclear Information System (INIS)

    Poncelet, B.; Baleriiaux, D.; struyven, J.; Segebarth, C.

    1989-01-01

    In MRI angiography two basis images are measured which only differ by the signal intensity of the flowing blood in the vessels. Subtraction of these two images produces a high contrast-to-noise representation of the vessels. Contrast between stationary tissues and flowing blood is changed, for one image compared to the second one, using a selective modification of the phase of the signal from the flowing blood, and/or using a selective modification of its longitudinal magnetization: The macroscopic spin motions along the selection and the measurement gradient directions affect the phase of the nuclear signal; assuming constant velocity, the phase is proportional to the velocity and to the first moment of the gradient waveforms applied. This work concentrates on the generarion of MRI angiograms, following a phase-based approach, of the carotid bifurcation and of different intracranical regions including the carotid syphon and the circle of Willis. (author). 21 refs.; 3 figs

  12. MRI zoo

    DEFF Research Database (Denmark)

    Laustsen, Christoffer

    The basic idea was to use MRI to produce a sequence of 3D gray scale image slices of various animals, subsequentlyimaged with a clinical CT system. For this purpose, these animals were used: toad, lungfish, python snake and a horseshoe crab. Each animal was sacrificed according to standard...... visually inspected, both in 2D and 3D, and compared with photographs and anatomy atlases found at library and on the internet....

  13. MRI of the Chest

    Medline Plus

    Full Text Available ... affecting the MRI images, these objects can become projectiles within the MRI scanner room and may cause ... MRI has proven valuable in diagnosing a broad range of conditions, including cancer, heart and vascular disease, ...

  14. MRI of the Chest

    Medline Plus

    Full Text Available ... or patients with claustrophobia. Other MRI machines are open on the sides (open MRI). Open units are especially helpful for examining larger patients or those with claustrophobia. Newer open MRI units provide very high quality images for ...

  15. MRI (Magnetic Resonance Imaging)

    Science.gov (United States)

    ... Procedures Medical Imaging MRI (Magnetic Resonance Imaging) MRI (Magnetic Resonance Imaging) Share Tweet Linkedin Pin it More sharing options Linkedin Pin it Email Print Magnetic Resonance Imaging (MRI) is a medical imaging procedure for ...

  16. MRI of the Chest

    Medline Plus

    Full Text Available ... does not completely surround you. Some newer MRI machines have a larger diameter bore which can be ... size patients or patients with claustrophobia. Other MRI machines are open on the sides (open MRI). Open ...

  17. MRI of the Chest

    Medline Plus

    Full Text Available ... in the first three to four months of pregnancy unless the potential benefit from the MRI exam ... the MRI Safety page for more information about pregnancy and MRI. If you have claustrophobia (fear of ...

  18. MRI of the Chest

    Medline Plus

    Full Text Available ... News Physician Resources Professions Site Index A-Z Magnetic Resonance Imaging (MRI) - Chest Magnetic resonance imaging (MRI) ... clearer and more detailed than with other imaging methods. This detail makes MRI an invaluable tool in ...

  19. Play the MRI Game

    Science.gov (United States)

    ... Teachers' Questionnaire MRI Play MRI the Magnetic Miracle Game About the game In the MRI imaging technique, strong magnets and ... last will in Paris. Play the Blood Typing Game Try to save some patients and learn about ...

  20. Animal MRI Core

    Data.gov (United States)

    Federal Laboratory Consortium — The Animal Magnetic Resonance Imaging (MRI) Core develops and optimizes MRI methods for cardiovascular imaging of mice and rats. The Core provides imaging expertise,...

  1. pH responsive N-succinyl chitosan/Poly (acrylamide-co-acrylic acid hydrogels and in vitro release of 5-fluorouracil.

    Directory of Open Access Journals (Sweden)

    Shahid Bashir

    Full Text Available There has been significant progress in the last few decades in addressing the biomedical applications of polymer hydrogels. Particularly, stimuli responsive hydrogels have been inspected as elegant drug delivery systems capable to deliver at the appropriate site of action within the specific time. The present work describes the synthesis of pH responsive semi-interpenetrating network (semi-IPN hydrogels of N-succinyl-chitosan (NSC via Schiff base mechanism using glutaraldehyde as a crosslinking agent and Poly (acrylamide-co-acrylic acid(Poly (AAm-co-AA was embedded within the N-succinyl chitosan network. The physico-chemical interactions were characterized by Fourier transform infrared (FTIR, X-ray diffraction (XRD, thermogravimetric analysis (TGA, and field emission scanning electron microscope (FESEM. The synthesized hydrogels constitute porous structure. The swelling ability was analyzed in physiological mediums of pH 7.4 and pH 1.2 at 37°C. Swelling properties of formulations with various amounts of NSC/ Poly (AAm-co-AA and crosslinking agent at pH 7.4 and pH 1.2 were investigated. Hydrogels showed higher swelling ratios at pH 7.4 while lower at pH 1.2. Swelling kinetics and diffusion parameters were also determined. Drug loading, encapsulation efficiency, and in vitro release of 5-fluorouracil (5-FU from the synthesized hydrogels were observed. In vitro release profile revealed the significant influence of pH, amount of NSC, Poly (AAm-co-AA, and crosslinking agent on the release of 5-FU. Accordingly, rapid and large release of drug was observed at pH 7.4 than at pH 1.2. The maximum encapsulation efficiency and release of 5-FU from SP2 were found to be 72.45% and 85.99%, respectively. Kinetics of drug release suggested controlled release mechanism of 5-FU is according to trend of non-Fickian. From the above results, it can be concluded that the synthesized hydrogels have capability to adapt their potential exploitation as targeted oral drug delivery carriers.

  2. Composition-property relationships in multifunctional hollow mesoporous carbon nanosystems for PH-responsive magnetic resonance imaging and on-demand drug release

    Science.gov (United States)

    Zhang, Shengjian; Qian, Xiaoqing; Zhang, Linlin; Peng, Weijun; Chen, Yu

    2015-04-01

    The construction of intelligent stimuli-responsive nanosystems can substantially improve the sensitivity/resolution/specificity of diagnostic imaging and enhance the therapeutic efficiency of chemotherapy for cancer treatment. This work reports on a generic construction strategy to achieve a multiple stimuli-responsive theranostic system for cancer simply by optimizing the chemical compositions of inorganic nanoplatforms to avoid the tedious and complicated synthetic procedure for traditional organic or organic/inorganic nanosystems. Based on the ``breaking up'' nature of manganese oxides and specific features of the carbonaceous framework to interact with aromatic drug molecules, manganese oxide nanoparticles were elaborately integrated into hollow mesoporous carbon nanocapsules by a simple in situ framework redox strategy to realize concurrent pH-sensitive T1-weighted magnetic resonance imaging (MRI) and pH-/HIFU-responsive on-demand drug release. The ultrasensitive disease-triggered MRI performance has been successfully demonstrated by a 52.5-fold increase of longitudinal relaxivity (r1 = 10.5 mM-1 s-1) and on nude mice 4T1 xenograft. The pH- and HIFU-triggered doxorubicin release and enhanced therapeutic outcome against multidrug resistance of cancer cells were systematically confirmed. In particular, the fabricated inorganic composite nanocapsules were found to feature unique biological behaviours, such as antimetastasis effect, extremely low hemolysis against red blood cells and high in vivo histocompatibility. This report on the successful construction of a pure inorganic nanosystem with multiple stimuli-responsivenesses may pave the way to new methods for the development of intelligent nanofamilies for cancer therapy.The construction of intelligent stimuli-responsive nanosystems can substantially improve the sensitivity/resolution/specificity of diagnostic imaging and enhance the therapeutic efficiency of chemotherapy for cancer treatment. This work reports

  3. Magnetic Resonance Imaging (MRI) Safety

    Science.gov (United States)

    ... News Physician Resources Professions Site Index A-Z Magnetic Resonance Imaging (MRI) Safety What is MRI and how ... What is MRI and how does it work? Magnetic resonance imaging, or MRI, is a way of obtaining ...

  4. MRI of the Chest

    Medline Plus

    Full Text Available ... examination poses almost no risk to the average patient when appropriate safety guidelines are followed. If sedation is used, there ... patient story here Images × ... Imaging (MRI) Safety Contrast Materials MRI Safety During Pregnancy Images related ...

  5. MRI of the Chest

    Medline Plus

    Full Text Available ... to a CD or uploaded to a digital cloud server. MRI of the chest gives detailed pictures ... over time. top of page What are the benefits vs. risks? Benefits MRI is a noninvasive imaging ...

  6. MRI of the Chest

    Medline Plus

    Full Text Available ... images and send a signed report to your primary care or referring physician, who will share the ... This detail makes MRI an invaluable tool in early diagnosis and evaluation of cardiovascular conditions. MRI has ...

  7. MRI of the Chest

    Medline Plus

    Full Text Available ... metallic items, which can distort MRI images removable dental work pens, pocket knives and eyeglasses body piercings In most cases, an MRI exam is safe for patients with metal implants, except for a few types. ...

  8. MRI of the Chest

    Medline Plus

    Full Text Available ... interfere with the magnetic field of the MRI unit, metal and electronic items are not allowed in ... does the equipment look like? The traditional MRI unit is a large cylinder-shaped tube surrounded by ...

  9. MRI of the Chest

    Medline Plus

    Full Text Available ... items, which can distort MRI images removable dental work pens, pocket knives and eyeglasses body piercings In most cases, an MRI exam is safe for patients with metal implants, except for a ...

  10. MRI of the Chest

    Medline Plus

    Full Text Available ... metallic items, which can distort MRI images removable dental work pens, pocket knives and eyeglasses body piercings ... tomography (CT) scans, MRI does not utilize ionizing radiation. Instead, radiofrequency pulses re-align hydrogen atoms that ...

  11. MRI of the Chest

    Medline Plus

    Full Text Available ... women should not have this exam in the first three to four months of pregnancy unless the ... not to have an MRI exam during the first trimester unless medically necessary. MRI may not always ...

  12. MRI of the Chest

    Medline Plus

    Full Text Available ... important to assess the health and function of these structures (heart, valves, great vessels, etc.). top of ... room. In addition to affecting the MRI images, these objects can become projectiles within the MRI scanner ...

  13. MRI of the Chest

    Medline Plus

    Full Text Available ... conditions. MRI uses a powerful magnetic field, radio frequency pulses and a computer to produce detailed pictures ... may follow your regular daily routine and take food and medications as usual. Some MRI examinations may ...

  14. MRI of the Chest

    Medline Plus

    Full Text Available ... are the limitations of MRI of the Chest? What is MRI of the Chest? Magnetic resonance imaging ( ... heart, valves, great vessels, etc.). top of page What are some common uses of the procedure? MR ...

  15. MRI of the Chest

    Medline Plus

    Full Text Available ... is done because a potential abnormality needs further evaluation with additional views or a special imaging technique. ... MRI an invaluable tool in early diagnosis and evaluation of cardiovascular conditions. MRI has proven valuable in ...

  16. MRI of the Chest

    Medline Plus

    Full Text Available ... MRI scanners are air-conditioned and well-lit. Music may be played through the headphones to help ... used in MRI exams is less likely to produce an allergic reaction than the iodine-based contrast ...

  17. MRI of the Chest

    Medline Plus

    Full Text Available ... or headphones during the exam. MRI scanners are air-conditioned and well-lit. Music may be played ... the limitations of MRI of the Chest? High-quality images are assured only if you are able ...

  18. MRI of the Chest

    Science.gov (United States)

    ... MRI scanners are air-conditioned and well-lit. Music may be played through the headphones to help ... tissue and fluid, known as edema . MRI typically costs more and may take more time to perform ...

  19. MRI of the Chest

    Medline Plus

    Full Text Available ... MRI scanners are air-conditioned and well-lit. Music may be played through the headphones to help ... tissue and fluid, known as edema . MRI typically costs more and may take more time to perform ...

  20. MRI of the Chest

    Medline Plus

    Full Text Available ... clearer and more detailed than with other imaging methods. This detail makes MRI an invaluable tool in ... might be obscured by bone with other imaging methods. The contrast material used in MRI exams is ...

  1. MRI of the Chest

    Medline Plus

    Full Text Available ... top of page What are the benefits vs. risks? Benefits MRI is a noninvasive imaging technique that ... risking the side effects of conventional (catheter) angiography . Risks The MRI examination poses almost no risk to ...

  2. MRI of the Chest

    Medline Plus

    Full Text Available ... MRI examination poses almost no risk to the average patient when appropriate safety guidelines are followed. If ... tissue and fluid, known as edema . MRI typically costs more and may take more time to perform ...

  3. MRI of the Chest

    Medline Plus

    Full Text Available ... other internal body structures. MRI does not use ionizing radiation (x-rays). Detailed MR images allow physicians ... computed tomography (CT) scans, MRI does not utilize ionizing radiation. Instead, radiofrequency pulses re-align hydrogen atoms ...

  4. MRI of the Chest

    Medline Plus

    Full Text Available ... This detail makes MRI an invaluable tool in early diagnosis and evaluation of cardiovascular conditions. MRI has ... have special pediatric considerations. The teddy bear denotes child-specific content. Related Articles and Media MR Angiography ( ...

  5. Canalis basilaris medianus: MRI

    International Nuclear Information System (INIS)

    Jacquemin, C.; Bosley, T.M.; Al Saleh, M.; Mullaney, P.

    2000-01-01

    We report the MRI appearances of an developmental anatomical variant of the basiocciput, with neuroimaging findings (CT and MRI). Such variants are commonly asymptomatic, but may be associated with episodes of meningitis. (orig.)

  6. MRI in acute poliomyelitis

    Energy Technology Data Exchange (ETDEWEB)

    Kornreich, L. [Imaging Department, The Schneider Children`s Medical Centre of Israel, Kaplan Street, Petah Tiqva 49202 (Israel)]|[Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv (Israel); Dagan, O. [The Intensive Care Unit, The Schneider Children`s Medical Centre of Israel, Beilinson Medical Campus, Petah Tiqva (Israel)]|[Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv (Israel); Grunebaum, M. [Imaging Department, The Schneider Children`s Medical Centre of Israel, Kaplan Street, Petah Tiqva 49202 (Israel)]|[Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv (Israel)

    1996-05-01

    MRI can be used in the diagnosis of anterior horn infection and for assessing the extent of disease. There are no specific MRI signs to differentiate between the various possible pathogens. This is demonstrated in the present case of poliomyelitis, in which MRI of the spine played an important role in establishing the diagnosis. (orig.). With 1 fig.

  7. MRI in acute poliomyelitis

    International Nuclear Information System (INIS)

    Kornreich, L.; Dagan, O.; Grunebaum, M.

    1996-01-01

    MRI can be used in the diagnosis of anterior horn infection and for assessing the extent of disease. There are no specific MRI signs to differentiate between the various possible pathogens. This is demonstrated in the present case of poliomyelitis, in which MRI of the spine played an important role in establishing the diagnosis. (orig.). With 1 fig

  8. MRI in psychiatry

    International Nuclear Information System (INIS)

    Mulert, Christoph; Shenton, Martha E.

    2014-01-01

    This is the first comprehensive textbook on the use of MRI in psychiatry covering imaging techniques, brain systems and a review of findings in different psychiatric disorders. The book is divided into three sections, the first of which covers in detail all the major MRI-based methodological approaches available today, including fMRI, EEG-fMRI, DTI, and MR spectroscopy. In addition, the role of MRI in imaging genetics and combined brain stimulation and imaging is carefully explained. The second section provides an overview of the different brain systems that are relevant for psychiatric disorders, including the systems for perception, emotion, cognition, and reward. The final part of the book presents the MRI findings that are obtained in all the major psychiatric disorders using the previously discussed techniques. Numerous carefully chosen images support the informative text, making this an ideal reference work for all practitioners and trainees with an interest in this flourishing field.

  9. MRI in psychiatry

    Energy Technology Data Exchange (ETDEWEB)

    Mulert, Christoph [UKE, Hamburg (Germany). Psychiatry Neuroimaging Branch; Shenton, Martha E. (ed.) [Harvard Medical School, Boston, MA (United States). Dept. of Psychiatry and Radiology

    2014-07-01

    This is the first comprehensive textbook on the use of MRI in psychiatry covering imaging techniques, brain systems and a review of findings in different psychiatric disorders. The book is divided into three sections, the first of which covers in detail all the major MRI-based methodological approaches available today, including fMRI, EEG-fMRI, DTI, and MR spectroscopy. In addition, the role of MRI in imaging genetics and combined brain stimulation and imaging is carefully explained. The second section provides an overview of the different brain systems that are relevant for psychiatric disorders, including the systems for perception, emotion, cognition, and reward. The final part of the book presents the MRI findings that are obtained in all the major psychiatric disorders using the previously discussed techniques. Numerous carefully chosen images support the informative text, making this an ideal reference work for all practitioners and trainees with an interest in this flourishing field.

  10. Superconductive MRI system, FLEXARTTM

    International Nuclear Information System (INIS)

    Suzuki, Hirokazu; Nishikawa, Mineki; Goro, Takehiko

    1994-01-01

    Since the establishment of TAMI (Toshiba America MRI Inc.) in 1989, it has been jointly working with Toshiba on developing a new infrastructure for computer and software technologies to be applied to new MRI (magnetic resonance imaging) systems. As a result of these efforts, the first product of a new series of MRI systems has been introduced on the market. Known as FLEXART TM (a newly created word combining FLEXible and ART), this MRI system incorporates a new 32-bit RISC computer and a new controller for pulse sequences and data acquisition. The product concepts of FLEXART TM are high image quality, high patient throughput, and ease of use, all of which are necessary features for an MRI system in the premium mid-field MRI market segment. (author)

  11. MRI of meningioma

    International Nuclear Information System (INIS)

    Yamamoto, Yoshio; Hiraki, Yoshio; Kaji, Mitumasa

    1988-01-01

    MRI has gained a prominent position in the diagnosis of brain tumors. We examined 30 cases of meningiomas and distinguished their subtype according to the criteria of Rubinic histology. We discussed the MRI findings and compared then with X-CT findings so to their intensity, delination of tumors, whether accompanied by peripheral edema, and T 1 values. MRI delinated the tumors as well as CE-CT. No remarkable difference was found between the subtypes. (author)

  12. MRI assessment program

    International Nuclear Information System (INIS)

    1988-05-01

    Usage, cost and efficacy data from the MRI Assessment Program to 30 March 1988 is presented, as a continuation of an earlier analysis. Analysis has been performed on data from 8565 examinations relating to 7997 patients at 4 hospitals. MRI was used mainly for examination of the head and spine. Some details of the follow up studies being conducted on selected patients and disease categories are given. A consensus statement is included which summaries the view of the Technical Committee on the potential applications of MRI in Australia. The MRI unit quench incident at Royal Adelaide Hospital is described. Refs., 10 figs., tabs

  13. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... or patients with claustrophobia. Other MRI machines are open on the sides (open MRI). Open units are especially helpful for examining larger patients or those with claustrophobia. Newer open MRI units provide very high quality images for ...

  14. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... does not completely surround you. Some newer MRI machines have a larger diameter bore which can be ... size patients or patients with claustrophobia. Other MRI machines are open on the sides (open MRI). Open ...

  15. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... in the first three to four months of pregnancy unless the potential benefit from the MRI exam ... the MRI Safety page for more information about pregnancy and MRI. If you have claustrophobia (fear of ...

  16. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... information on the chemicals present in the body's cells, may also be performed during the MRI exam ... medically necessary. MRI may not always distinguish between cancer tissue and fluid, known as edema . MRI typically ...

  17. MRI in sarcoglycanopathies

    DEFF Research Database (Denmark)

    Tasca, Giorgio; Monforte, Mauro; Díaz-Manera, Jordi

    2018-01-01

    OBJECTIVES: To characterise the pattern and spectrum of involvement on muscle MRI in a large cohort of patients with sarcoglycanopathies, which are limb-girdle muscular dystrophies (LGMD2C-2F) caused by mutations in one of the four genes coding for muscle sarcoglycans. METHODS: Lower limb MRI sca...

  18. MRI of the Chest

    Medline Plus

    Full Text Available ... Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info About Us News Physician ... absolutely necessary for medical treatment. See the MRI Safety page for more information about pregnancy and MRI. ...

  19. MRI of the Chest

    Medline Plus

    Full Text Available ... internal body structures. MRI does not use ionizing radiation (x-rays). Detailed MR images allow physicians to evaluate various ... seen by other imaging modalities, such as chest x-ray or CT. A special form of MRI called ...

  20. MRI of the Chest

    Medline Plus

    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician ... Magnetic resonance imaging (MRI) is a noninvasive medical test that physicians use to diagnose medical conditions. MRI ...

  1. MRI of the Chest

    Medline Plus

    Full Text Available ... fitting and has no metal fasteners. Guidelines about eating and drinking before an MRI exam vary with the specific exam and with the imaging facility. Unless you are told otherwise, you may follow your regular daily routine and take food and medications as usual. Some MRI examinations may ...

  2. MRI of the Chest

    Medline Plus

    Full Text Available ... metallic items, which can distort MRI images removable dental work pens, pocket knives and eyeglasses body piercings In most cases, an MRI exam is safe for patients with metal implants, except for a few types. People with the ...

  3. MRI of neonatal encephalopathy

    International Nuclear Information System (INIS)

    Khong, P.L.; Lam, B.C.C.; Tung, H.K.S.; Wong, V.; Chan, F.L.; Ooi, G.C.

    2003-01-01

    We present the magnetic resonance imaging (MRI) findings in neonatal encephalopathy, including hypoxic-ischaemic encephalopathy, perinatal/neonatal stroke, metabolic encephalopathy from inborn errors of metabolism, congenital central nervous system infections and birth trauma. The applications of advanced MRI techniques, such as diffusion-weighted imaging and magnetic resonance spectroscopy are emphasized

  4. MRI of the Chest

    Medline Plus

    Full Text Available ... body structures. MRI does not use ionizing radiation (x-rays). Detailed MR images allow physicians to evaluate various ... seen by other imaging modalities, such as chest x-ray or CT. A special form of MRI called ...

  5. MRI of the Chest

    Medline Plus

    Full Text Available ... structure of an organ and how it is working. MRI enables the discovery of abnormalities that might be obscured by bone with other imaging methods. The contrast material used in MRI exams is less likely to produce an allergic reaction than the ...

  6. MRI of the Chest

    Medline Plus

    Full Text Available ... computer to produce detailed pictures of organs, soft tissues, bone and virtually all other internal body structures. MRI ... cancer, heart and vascular disease, heart valve abnormalities, bone and other soft tissue abnormalities of the chest. MRI is also useful ...

  7. MRI of the Chest

    Medline Plus

    Full Text Available ... other internal body structures. MRI does not use ionizing radiation (x-rays). Detailed MR images allow physicians to ... computed tomography (CT) scans, MRI does not utilize ionizing radiation. Instead, radiofrequency pulses re-align hydrogen atoms that ...

  8. MRI of the Chest

    Medline Plus

    Full Text Available ... Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us ... absolutely necessary for medical treatment. See the MRI Safety page for more information about pregnancy and MRI. ...

  9. MRI in head trauma

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Jin Kyo [Shin Wha Hospital, Seoul (Korea, Republic of)

    1986-02-15

    In the diagnosis of head injury, Magnetic Resonance Imaging (MRI), like CT, is an effective method of distinguishing between intracerebral and extracerebral lesions. In our experience of MRI, early hematomas are almost isointense by Saturation Recovery (SR) method, so these must be performed with Spin Echo (SE) method for better visualization of hematomas. Isodense subdural hematomas, which is a diagnostic dilemma on CT images, are clearly seen on MRI. Delayed hematomas or residual parenchymal lesions are better demonstrated on MRI than on CT. Direct cornal, sagittal images and multiplanar facility of MRI provides excellent visualization of the the location and shape of extracerebral collection of hematoma. For the screening of head traumas, SE method is a technique of choice because of its excellent sensitivity within limited time.

  10. Mobius syndrome: MRI features

    International Nuclear Information System (INIS)

    Markarian, Maria F.; Villarroel, Gonzalo M.; Nagel, Jorge R.

    2003-01-01

    Purpose: Mobius Syndrome or congenital facial diplegia is associated with paralysis of the lateral gaze movements. This syndrome may include other cranial nerve palsies and be associated to musculoskeletal anomalies. Our objective is to show the MRI findings in Mobius Syndrome. Material and methods: MRI study was performed in 3 patients with clinic diagnosis of Mobius Syndrome. RMI (1.5T); exams included axial FSE (T1 and T2), FLAIR, SE/EPI, GRE/20, sagittal FSE T2 , coronal T1, diffusion, angio MRI and Spectroscopy sequences. Results: The common features of this syndrome found in MRI were: depression or straightening of the floor of the fourth ventricle, brainstem anteroposterior diameter diminution, morphologic alteration of the pons and medulla oblongata and of the hypoglossal nuclei as well as severe micrognathia. Conclusion: The morphologic alterations of Mobius Syndrome can be clearly identified by MRI; this method has proved to be a useful diagnostic examination. (author)

  11. MRI in head trauma

    International Nuclear Information System (INIS)

    Hong, Jin Kyo

    1986-01-01

    In the diagnosis of head injury, Magnetic Resonance Imaging (MRI), like CT, is an effective method of distinguishing between intracerebral and extracerebral lesions. In our experience of MRI, early hematomas are almost isointense by Saturation Recovery (SR) method, so these must be performed with Spin Echo (SE) method for better visualization of hematomas. Isodense subdural hematomas, which is a diagnostic dilemma on CT images, are clearly seen on MRI. Delayed hematomas or residual parenchymal lesions are better demonstrated on MRI than on CT. Direct cornal, sagittal images and multiplanar facility of MRI provides excellent visualization of the the location and shape of extracerebral collection of hematoma. For the screening of head traumas, SE method is a technique of choice because of its excellent sensitivity within limited time.

  12. Smart dendrimer-based nanogel for enhancing 5-fluorouracil ...

    Indian Academy of Sciences (India)

    Author for correspondence (nckhoavnn@yahoo.com) chemical properties of the ..... accounting for 90% of loaded 5-FU from dialysis membrane, whereas ... of the NIPAM layer-coated dendrimer contributed to control the drug sustainably from ...

  13. New Dendrimer-Based Nanoparticles Enhance Curcumin Solubility.

    Science.gov (United States)

    Falconieri, Maria Cristina; Adamo, Mauro; Monasterolo, Claudio; Bergonzi, Maria Camilla; Coronnello, Marcella; Bilia, Anna Rita

    2017-03-01

    Curcumin, the main curcuminoid of the popular Indian spice turmeric, is a potent chemopreventive agent and useful in many different diseases. A major limitation of applicability of curcumin as a health promoting and medicinal agent is its extremely low bioavailability due to efficient first pass metabolism, poor gastrointestinal absorption, rapid elimination, and poor aqueous solubility. In the present study, nanotechnology was selected as a choice approach to enhance the bioavailability of the curcuminis. A new polyamidoamine dendrimer (G0.5) was synthesized, characterized, and tested for cytotoxicity in human breast cancer cells (MCF-7). No cytotoxicity of G0.5 was found in the range between 10 -3 and 3 × 10 -8  M. Consequently, G0.5 was used to prepare spherical nanoparticles of ca. 150 nm, which were loaded with curcumin [molar ratio G0.5/curcumin 1 : 1 (formulation 1) and 1 : 0.5 (formulation 2)]. Remarkably, the occurrence of a single population of nanoparticles having an excellent polydispersity index (solubility of curcumin was increased ca. 415 and 150 times with respect to the unformulated drug, respectively, for formulation 1 and formulation 2. The release of curcumin from the nanoparticles showed an interesting prolonged and sustained release profile. Georg Thieme Verlag KG Stuttgart · New York.

  14. Dendrimer-based biosensor for chemiluminescent detection of DNA hybridization

    International Nuclear Information System (INIS)

    Liu, P.; Hun, X.; Qing, H.

    2011-01-01

    We report on a highly sensitive chemiluminescent (CL) biosensor for the sequence-specific detection of DNA using a novel bio barcode DNA probe modified with gold nanoparticles that were covered with a dendrimer. The modified probe is composed of gold nanoparticles, a dendrimer, the CL reagent, and the DNA. The capture probe DNA was immobilized on magnetic beads covered with gold. It first hybridizes with the target DNA and then with one terminal end of the signal DNA on the barcoded DNA probe. CL was generated by adding H 2 O 2 and Co(II) ions as the catalyst. The immobilization of dendrimer onto the gold nanoparticles can significantly enhance sensitivity and gives a detection limit of 6 fmol L -1 of target DNA. (author)

  15. Formulation and Development of Dendrimer-Based Transdermal ...

    African Journals Online (AJOL)

    Shandong Traditional Chinese Medicine University, Jinan 250012, China ... system for the management of some diseased conditions. Keywords: Dendrimers ... anti-inflammatory and analgesic activity [3]. ..... Cost-effective management of.

  16. Fullerene and dendrimer based nano-composite gas separation membranes

    NARCIS (Netherlands)

    Sterescu, D.M.

    2007-01-01

    This thesis describes the development of new materials for membrane based gas separation processes. Long-term stable, loosely packed (high free volume) amorphous polymer films were prepared by introduction of super-molecular pendant groups, which possess hardsphere properties to avoid dense

  17. Thiophene dendrimer-based low donor content solar cells

    Science.gov (United States)

    Stoltzfus, Dani M.; Ma, Chang-Qi; Nagiri, Ravi C. R.; Clulow, Andrew J.; Bäuerle, Peter; Burn, Paul L.; Gentle, Ian R.; Meredith, Paul

    2016-09-01

    Low donor content solar cells containing polymeric and non-polymeric donors blended with fullerenes have been reported to give rise to efficient devices. In this letter, we report that a dendrimeric donor can also be used in solution-processed low donor content devices when blended with a fullerene. A third generation dendrimer containing 42 thiophene units (42T) was found to give power conversion efficiencies of up to 3.5% when blended with PC70BM in optimized devices. The best efficiency was measured with 10 mole percent (mol. %) of 42T in PC70BM and X-ray reflectometry showed that the blends were uniform. Importantly, while 42T comprised 10 mol. % of the film, it made up 31% of the film by volume. Finally, it was found that solvent annealing was required to achieve the largest open circuit voltage and highest device efficiencies.

  18. Dendrimer-protein interactions versus dendrimer-based nanomedicine.

    Science.gov (United States)

    Shcharbin, Dzmitry; Shcharbina, Natallia; Dzmitruk, Volha; Pedziwiatr-Werbicka, Elzbieta; Ionov, Maksim; Mignani, Serge; de la Mata, F Javier; Gómez, Rafael; Muñoz-Fernández, Maria Angeles; Majoral, Jean-Pierre; Bryszewska, Maria

    2017-04-01

    Dendrimers are hyperbranched polymers belonging to the huge class of nanomedical devices. Their wide application in biology and medicine requires understanding of the fundamental mechanisms of their interactions with biological systems. Summarizing, electrostatic force plays the predominant role in dendrimer-protein interactions, especially with charged dendrimers. Other kinds of interactions have been proven, such as H-bonding, van der Waals forces, and even hydrophobic interactions. These interactions depend on the characteristics of both participants: flexibility and surface charge of a dendrimer, rigidity of protein structure and the localization of charged amino acids at its surface. pH and ionic strength of solutions can significantly modulate interactions. Ligands and cofactors attached to a protein can also change dendrimer-protein interactions. Binding of dendrimers to a protein can change its secondary structure, conformation, intramolecular mobility and functional activity. However, this strongly depends on rigidity versus flexibility of a protein's structure. In addition, the potential applications of dendrimers to nanomedicine are reviwed related to dendrimer-protein interactions. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Formulation and Development of Dendrimer-Based Transdermal ...

    African Journals Online (AJOL)

    Methods: The patches were prepared by solvent casting evaporation technique using 3-factor, 3-level Box-Behnken design. The patches were evaluated for physical appearance, thickness, weight variation, folding endurance, drug content uniformity, tensile strength, moisture absorption and moisture loss, in vitro drug ...

  20. Nanoparticulate platinum films on gold using dendrimer-based wet ...

    Indian Academy of Sciences (India)

    Central Electrochemical Research Institute, Karaikudi 630 006, India. E-mail: ... deposition methods for applications involving thin films, e.g., catalysis. Deposition of platinum .... The spectrum recorded at 0.3 V shows a mixed control behaviour ...

  1. Indications for body MRI

    Energy Technology Data Exchange (ETDEWEB)

    Dujardin, M. [Department of Radiology, Vrije Universiteit Brussel, BEFY, Laarbeeklaan 101, 1090 Brussels (Belgium)], E-mail: martine.dujardin@gmail.com; Vandenbroucke, F. [Department of Radiology, Vrije Universiteit Brussel, Laarbeeklaan 101, 1090 Brussels (Belgium)], E-mail: frederik.vandenbroucke@az.vub.ac.be; Boulet, C. [Department of Radiology, Vrije Universiteit Brussel, Laarbeeklaan 101, 1090 Brussels (Belgium)], E-mail: cedric.boulet@az.vub.ac.be; Op de Beeck, B. [Department of Radiology, UZA and Vrije Universiteit Brussel, Laarbeeklaan 101, 1090 Brussels (Belgium)], E-mail: bart.op.de.beeck@uza.be; Mey, J. de [Department of Radiology, Vrije Universiteit Brussel, BEFY, Laarbeeklaan 101, 1090 Brussels (Belgium)], E-mail: johan.demey@az.vub.ac.be

    2008-02-15

    The lack of ionizing radiation use in MRI makes the high spatial resolution technique very appealing. Also, the easy access to multiplanar imaging and the fact that gadolinium-DTPA is well tolerated and not nephrotoxic makes MRI a robust alternative in the healthy as well as the renal compromised patient. Furthermore, MRI adds advanced possibility for tissue characterization and pathology detection and dynamic imaging can be performed. Specific contrast agents specific to the hepatobiliary or the reticuloendothelial system can help with additional information in problem cases. The role of MRI for different organs is discussed and a review of the literature is given. We concluded that MRI is considered a useful and non-invasive diagnostic tool for the detection of hepatic iron concentration, to correct misdiagnosis (pseudolesions) from US and CT in focal steatosis and to help with focal lesion detection and characterization, in the healthy and especially in the cirrhotic liver, where MRI is superior to CT. Moreover, MRCP is excellent for identifying the presence and the level of biliary obstruction in malignant invasion and is considered in the literature as a non-invasive screening tool for common bile duct stones, appropriately selecting candidates for preoperative ERCP and sparing others the need for an endoscopic procedure with its associated complications. MRI is the first choice modality for adrenal evaluation in contemporary medical imaging. It is a useful examination in renal as well as splenic pathology and best assesses loco-regional staging, i.e. arterial involvement in pancreatic cancer.

  2. Explaining MRI examinations DVD

    International Nuclear Information System (INIS)

    Takatsu, Yasuo; Komeda, Takuya

    2010-01-01

    When conducting MRI examinations, there are various things to be careful of. There is often stress related to the MRI examinations, so in order to perform an examination safely and smoothly, sufficient explanation must be given. An explanation of what to do and what not to do during an examination should be outlined in a brochure given to patients before the examination. There may be many patients who have misgivings about their MRI examinations, so to reduce their anxiousness and deepen their understanding of MRI examinations and to improve the safety and effiency of MRI examinations,; we created a DVD about MRI examinations. We gathered MRI-related safety information and instructions, and assessed the effect that the information might have on patients. We started a workgroup for a project to plan and record a video according to the Storyboard. When editing, we reviewed the length of each segment, the amount of information on screen, and the overall length of the DVD. We discussed the issue within the workgroup and had hospital approval. It was possible for us to complete it without depending on the supplier and the cost was kept to a minimum. Finally, we decided on a viewing location. We asked a hospital volunteers to see a complete DVD and we evaluated their responses by questionnaires. As the result, their understanding and anxieties related to MRI examinations were alleviated, as expected. Their anxiety seemed to be eased. Patients also seemed to have a deeper understanding of MRI examinations having seen an examination being conducted. (author)

  3. MRI of 'brain death'

    International Nuclear Information System (INIS)

    Nishino, Shigeki; Itoh, Takahiko; Tuchida, Shohei; Kinugasa, Kazushi; Asari, Shoji; Nishimoto, Akira; Sanou, Kazuo.

    1990-01-01

    Magnetic resonance imaging (MRI) was undertaken for two patients who suffered from severe cerebrovascular diseases and were clinically brain dead. The MRI system we used was Resona (Yokogawa Medical Systems, superconductive system 0.5 T) and the CT apparatus was Toshiba TCT-300. Initial CT and MRI were undertaken as soon as possible after admission, and repeated sequentially. After diagnosis of brain death, we performed angiography to determine cerebral circulatory arrest, and MRI obtained at the same time was compared with the angiogram and CT. Case 1 was a 77-year-old man who was admitted in an unconscious state. CT and MRI on the second day after hospitalization revealed cerebellar infarction. He was diagnosed as brain dead on day 4. Case 2 was a 35-year-old man. When he was transferred to our hospital, he was in cardiorespiratory arrested. Cardiac resuscitation was successful but no spontaneous respiration appeared. CT and MRI on admission revealed right intracerebral hemorrhage. Angiography revealed cessation of contrast medium in intracranial vessels in both of the patients. We found no 'flow signal void sign' in the bilateral internal carotid and basilar arteries on MRI images in both cases after brain death. MRI, showing us the anatomical changes of the brain, clearly revealed brain herniations, even though only nuclear findings of 'brain tamponade' were seen on CT. But in Case 1, we could not see the infarct lesions in the cerebellum on MR images obtained after brain death. This phenomenon was caused by the whole brain ischemia masking the initial ischemic lesions. We concluded that MRI was useful not only the anatomical display of lesions and brain herniation with high contrast resolution but for obtaining information on cerebral circulation of brain death. (author)

  4. Magnetic Resonance Imaging (MRI) -- Head

    Science.gov (United States)

    ... News Physician Resources Professions Site Index A-Z Magnetic Resonance Imaging (MRI) - Head Magnetic resonance imaging (MRI) of the head uses a powerful ... the Head? What is MRI of the Head? Magnetic resonance imaging (MRI) is a noninvasive medical test that ...

  5. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... News Physician Resources Professions Site Index A-Z Magnetic Resonance Imaging (MRI) - Head Magnetic resonance imaging (MRI) of the head uses a powerful ... the Head? What is MRI of the Head? Magnetic resonance imaging (MRI) is a noninvasive medical test that ...

  6. MRI of the Chest

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    Full Text Available ... has any questions. Some implanted devices require a short period of time after placement (usually six weeks) ... center of the magnet. Some MRI units, called short-bore systems , are designed so that the magnet ...

  7. MRI of the Chest

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    Full Text Available ... any recent surgeries. Some conditions, such as severe kidney disease, may prevent you from being given gadolinium contrast ... an MRI. If you have a history of kidney disease or liver transplant, it will be necessary to ...

  8. MRI of the Chest

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    Full Text Available ... told otherwise, take your regular medications as usual. Leave jewelry at home and wear loose, comfortable clothing. ... contrast material except when absolutely necessary for medical treatment. See the MRI Safety page for more information ...

  9. MRI of the Chest

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    Full Text Available ... told otherwise, take your regular medications as usual. Leave jewelry at home and wear loose, comfortable clothing. ... contrast material except when absolutely necessary for medical treatment. See the MRI ... pocket knives and eyeglasses body piercings ...

  10. MRI of the Chest

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    Full Text Available ... imaging modalities (typically CT) or which are particularly well-suited to MR imaging. determine tumor size, extent, ... the exam. MRI scanners are air-conditioned and well-lit. Music may be played through the headphones ...

  11. MRI of the Chest

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    Full Text Available ... metallic items, which can distort MRI images removable dental work pens, pocket knives and eyeglasses body piercings ... and send a signed report to your primary care or referring physician, who will share the results ...

  12. MRI of the Chest

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    Full Text Available ... a risk, depending on their nature and the strength of the MRI magnet. Many implanted devices will ... abnormalities where Chest CT is a preferred imaging test. MR imaging can assess blood flow without risking ...

  13. MRI of the Chest

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    Full Text Available ... scans, MRI does not utilize ionizing radiation. Instead, radiofrequency pulses re-align hydrogen atoms that naturally exist ... thumping sounds when the coils that generate the radiofrequency pulses are activated. Some centers provide earplugs, while ...

  14. MRI of the Chest

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    Full Text Available ... invaluable tool in early diagnosis and evaluation of cardiovascular conditions. MRI has proven valuable in diagnosing a broad range of conditions, including cancer, heart and vascular disease, heart valve abnormalities, bone and other soft tissue ...

  15. MRI of the Chest

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    Full Text Available ... Infants and young children usually require sedation or anesthesia to complete an MRI exam without moving. Whether ... A physician or nurse specializing in sedation or anesthesia for children should be available during the exam ...

  16. MRI of the Chest

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    Full Text Available ... imaging (MRI) exam. View full size with caption Pediatric Content Some imaging tests and treatments have special pediatric considerations. The teddy bear denotes child-specific content. ...

  17. MRI of the Chest

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    Full Text Available ... it may cause some medical devices to malfunction. Most orthopedic implants pose no risk, but you should ... or if you have asthma. The contrast material most commonly used for an MRI exam contains a ...

  18. MRI of the Chest

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    Full Text Available ... six weeks) before being safe for MRI examinations. Examples include but are not limited to: artificial heart ... usually completed within one hour but may occasionally take longer. top of page What will I experience ...

  19. MRI of the Chest

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    Full Text Available ... devices or metal in your body. Guidelines about eating and drinking before your exam vary between facilities. ... fitting and has no metal fasteners. Guidelines about eating and drinking before an MRI exam vary with ...

  20. MRI of the Chest

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    Full Text Available ... to a CD or uploaded to a digital cloud server. MRI of the chest gives detailed pictures ... community, you can search the ACR-accredited facilities database . This website does not provide cost information. The ...

  1. MRI of the Chest

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    Full Text Available ... three to four months of pregnancy unless the potential benefit from the MRI exam is assumed to outweigh the potential risks. Pregnant women should not receive injections of ...

  2. MRI features of chondroblastoma

    International Nuclear Information System (INIS)

    Cheng Xiaoguang; Liu Xia; Cheng Kebin; Liu Wei

    2009-01-01

    Objective: To evaluate the MR imaging features of chondroblastoma. Methods: MRI examinations of 20 patients with histological proven chondmblastoma were reviewed retrospectively. The MRI findings of chondroblastoma including the signal intensity, the shape, the growth patterns, and the surrounding bone marrow edema and the adjacent soft tissue edema, the periosteal reaction, the adjacent joint effusion were analyzed. Results: All 20 cases demonstrated heterogeneous MR signal intensity on T 1 WI and T 2 WI images and showed lobular margins. Sixteen cases demonstrated expansive growth patterns. Surrounding bone marrow edema was found in 18 cases and adjacent soft tissue edema in 14 cases. Periosteal reaction was identified in 6 cases. In 7 cases the tumor extended to adjacent soft tissue. Adjacent joint effusion was visible on MRI in 6 cases. Conclusion: Heterogeneous signal intensity, lobular margins and expansive growth pattern, adjacent bone marrow and soft tissue edema were the common features of chondroblastoma on MRI. (authors)

  3. MRI of the Chest

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    Full Text Available ... also provides movie-like sequential imaging of the cardiovascular system that is important to assess the health ... invaluable tool in early diagnosis and evaluation of cardiovascular conditions. MRI has proven valuable in diagnosing a ...

  4. MRI of the Chest

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    Full Text Available ... prior obstruction of blood flow). determine blood flow dynamics in the vessels and heart chambers. display lymph ... the magnet. Some MRI units, called short-bore systems , are designed so that the magnet does not ...

  5. MRI of the Chest

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    Full Text Available ... an MRI scan, but this is rare. Tooth fillings and braces usually are not affected by the magnetic field, but they may distort images of the facial area or brain, so you should let the ...

  6. MRI of the Chest

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    Full Text Available ... is not harmful, but it may cause some medical devices to malfunction. Most orthopedic implants pose no ... Chest? Magnetic resonance imaging (MRI) is a noninvasive medical test that physicians use to diagnose medical conditions. ...

  7. MRI of the Chest

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  8. MRI of the Chest

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    Full Text Available ... traditional MRI unit is a large cylinder-shaped tube surrounded by a circular magnet. You will lie ... your skin at the site of the IV tube insertion. Some patients may sense a temporary metallic ...

  9. MRI of the Breast

    Science.gov (United States)

    ... in evaluating women at high risk for breast cancer. MRI can successfully image the dense breast tissue common in younger women, and it can successfully image breast implants. Both of these are difficult to image using ...

  10. MRI of the Chest

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    Full Text Available ... metal in your body. Guidelines about eating and drinking before your exam vary between facilities. Unless you ... has no metal fasteners. Guidelines about eating and drinking before an MRI exam vary with the specific ...

  11. MRI of the Chest

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    Full Text Available ... MRI examinations may require you to receive an injection of contrast material into the bloodstream. The radiologist , ... the potential risks. Pregnant women should not receive injections of gadolinium contrast material except when absolutely necessary ...

  12. MRI of the Chest

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    Full Text Available ... will be removed. MRI exams generally include multiple runs (sequences), some of which may last several minutes. ... top of page Who interprets the results and how do I get them? A radiologist, a physician ...

  13. MRI of the Chest

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    Full Text Available ... others nearby harm. These items include: jewelry, watches, credit cards and hearing aids, all of which can ... top of page What are the benefits vs. risks? Benefits MRI is a noninvasive imaging technique that ...

  14. Arm MRI scan

    Science.gov (United States)

    ... MRI and ultrasound. In: Adam A, Dixon AK, Gillard JH, Schaefer-Prokop CM, eds. Grainger & Allison's Diagnostic ... Magnetic resonance imaging: In: Adam A, Dixon AK, Gillard JH, Schaefer-Prokop CM, eds. Grainger & Allison's Diagnostic ...

  15. Sinus MRI scan

    Science.gov (United States)

    ... CT, and MRI. In: Adam A, Dixon AK, Gillard JH, Schaefer-Prokop CM, eds. Grainger & Allison's Diagnostic ... Magnetic resonance imaging. In: Adam A, Dixon AK, Gillard JH, Schaefer-Prokop CM, eds. Grainger & Allison's Diagnostic ...

  16. Leg MRI scan

    Science.gov (United States)

    ... MRI and ultrasound. In: Adam A, Dixon AK, Gillard JH, Schaefer-Prokop CM, eds. Grainger & Allison's Diagnostic ... Magnetic resonance imaging: In: Adam A, Dixon AK, Gillard JH, Schaefer-Prokop CM, eds. Grainger & Allison's Diagnostic ...

  17. Knee MRI scan

    Science.gov (United States)

    ... MRI and ultrasound. In: Adam A, Dixon AK, Gillard JH, Schaefer-Prokop CM, eds. Grainger & Allison's Diagnostic ... Magnetic resonance imaging. In: Adam A, Dixon AK, Gillard JH, Schaefer-Prokop CM, eds. Grainger & Allison's Diagnostic ...

  18. MRI of the Chest

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    Full Text Available ... scanner. top of page How does the procedure work? Unlike conventional x-ray examinations and computed tomography ( ... MRI scanners are air-conditioned and well-lit. Music may be played through the headphones to help ...

  19. MRI of the Chest

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    Full Text Available ... provides movie-like sequential imaging of the cardiovascular system that is important to assess the health and ... the magnet. Some MRI units, called short-bore systems , are designed so that the magnet does not ...

  20. MRI of the Chest

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    Full Text Available ... you should let the radiologist know about them. Parents or family members who accompany patients into the ... intercom. Many MRI centers allow a friend or parent to stay in the room as long as ...

  1. MRI of the Chest

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    Full Text Available ... to produce detailed pictures of organs, soft tissues, bone and virtually all other internal body structures. MRI ... of the chest. assess disorders of the chest bones (vertebrae, ribs and sternum) and chest wall soft ...

  2. MRI of the Chest

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    Full Text Available ... contrast for an MRI. If you have a history of kidney disease or liver transplant, it will ... Thus, the child remains motionless allowing for good quality images. Jewelry and other accessories should be left ...

  3. MRI of the Chest

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    Full Text Available ... will hear and feel loud tapping or thumping sounds when the coils that generate the radiofrequency pulses ... use headphones to reduce the intensity of the sounds made by the MRI machine. You may be ...

  4. MRI of the Chest

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    Full Text Available ... food, or the environment, or if you have asthma. The contrast material most commonly used for an ... Infants and young children usually require sedation or anesthesia to complete an MRI exam without moving. Whether ...

  5. MRI of the Chest

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  6. MRI of the Chest

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    Full Text Available ... take food and medications as usual. Some MRI examinations may require you to receive an injection of ... for a mild sedative prior to your scheduled examination. Infants and young children usually require sedation or ...

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    Full Text Available ... magnetic field of the MRI unit, metal and electronic items are not allowed in the exam room. ... tell the technologist if you have medical or electronic devices in your body. These objects may interfere ...

  8. MRI of the Chest

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    Full Text Available ... The magnetic field is produced by passing an electric current through wire coils in most MRI units. ... signals that are detected by the coils. The electric current does not come in contact with the ...

  9. MRI of the Chest

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    Full Text Available ... have any devices or metal in your body. Guidelines about eating and drinking before your exam vary ... is loose-fitting and has no metal fasteners. Guidelines about eating and drinking before an MRI exam ...

  10. MRI of the Chest

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    Full Text Available ... Most MRI exams are painless. However, some patients find it uncomfortable to remain still during MR imaging. ... anxious, confused or in severe pain, you may find it difficult to lie still during imaging. A ...

  11. MRI of the Chest

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    Full Text Available ... More Info Images/Videos About Us News Physician Resources Professions Site Index A-Z Magnetic Resonance Imaging ( ... patient to have an allergy to a gadolinium-based contrast agent used for MRI than the iodine- ...

  12. MRI of the Chest

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    Full Text Available ... procedure performed? MRI examinations may be performed on outpatients or inpatients. You will be positioned on the ... and send a signed report to your primary care or referring physician, who will share the results ...

  13. MRI of the Chest

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    Full Text Available ... used in tattoos may contain iron and could heat up during an MRI scan, but this is ... injection. If you do not require sedation, no recovery period is necessary. You may resume your usual ...

  14. MRI of the Chest

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    Full Text Available ... prior to your scheduled examination. Infants and young children usually require sedation or anesthesia to complete an MRI exam without moving. Whether a child requires sedation depends on the child's age, intellectual ...

  15. MRI of the Chest

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    Full Text Available ... MRI exam, a physician, nurse or technologist will insert an intravenous (IV) catheter, also known as an ... physicians with expertise in several radiologic areas. Outside links: For the convenience of our users, RadiologyInfo .org ...

  16. MRI of the Chest

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    Full Text Available ... used in tattoos may contain iron and could heat up during an MRI scan, but this is ... a preferred imaging test. MR imaging can assess blood flow without risking the side effects of conventional ( ...

  17. MRI of the Chest

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    Full Text Available ... bear denotes child-specific content. Related Articles and Media MR Angiography (MRA) Magnetic Resonance Imaging (MRI) Safety ... the web pages found at these links. About Us | Contact Us | FAQ | Privacy | Terms of Use | Links | ...

  18. MRI of the Chest

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    Full Text Available ... you have any devices or metal in your body. Guidelines about eating and drinking before your exam ... soft tissues, bone and virtually all other internal body structures. MRI does not use ionizing radiation (x- ...

  19. MRI of the Chest

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    Full Text Available ... usual. Some MRI examinations may require you to receive an injection of contrast material into the bloodstream. ... outweigh the potential risks. Pregnant women should not receive injections of gadolinium contrast material except when absolutely ...

  20. MRI of the Chest

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    Full Text Available ... MRI) of the chest uses a powerful magnetic field, radio waves and a computer to produce detailed ... there’s a possibility you are pregnant. The magnetic field is not harmful, but it may cause some ...

  1. MRI of the Chest

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    Full Text Available ... their nature and the strength of the MRI magnet. Many implanted devices will have a pamphlet explaining ... large cylinder-shaped tube surrounded by a circular magnet. You will lie on a moveable examination table ...

  2. MRI of the Chest

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    Full Text Available ... allergies and whether there’s a possibility you are pregnant. The magnetic field is not harmful, but it ... if there is any possibility that they are pregnant. MRI has been used for scanning patients since ...

  3. MRI of the Chest

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    Full Text Available ... vessels, from almost any angle. MRI also provides movie-like sequential imaging of the cardiovascular system that ... headsets so that the child can watch a movie while the scan is being performed. Thus, the ...

  4. MRI of the Chest

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    Full Text Available ... to assess the anatomy and function of the heart and its blood flow. Tell your doctor about ... chest cavity, including the mediastinum , chest wall, pleura, heart and vessels, from almost any angle. MRI also ...

  5. MRI of the Chest

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    Full Text Available ... and how it is working. MRI enables the discovery of abnormalities that might be obscured by bone ... Radiology (ACR) and the Radiological Society of North America (RSNA), comprising physicians with expertise in several radiologic ...

  6. MRI of the Chest

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    Full Text Available ... it is useful to bring that to the attention of the scheduler before the exam and bring ... patient for magnetic resonance imaging (MRI) exam. View full size with caption Pediatric Content Some imaging tests ...

  7. MRI of the Chest

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    Full Text Available ... MRI scanners are air-conditioned and well-lit. Music may be played through the headphones to help you pass the time. In some cases, intravenous injection of contrast material ...

  8. MRI of the Chest

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    Full Text Available ... MRI) exam. View full size with caption Pediatric Content Some imaging tests and treatments have special pediatric considerations. The teddy bear denotes child-specific content. Related Articles and Media MR Angiography (MRA) Magnetic ...

  9. MRI of the Chest

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    Full Text Available ... contrast for an MRI. If you have a history of kidney disease or liver transplant, it will ... and send a signed report to your primary care or referring physician, who will share the results ...

  10. MRI of the Chest

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    Full Text Available ... may have. top of page What does the equipment look like? The traditional MRI unit is a ... traction devices and many types of life support equipment may distort the MR images and as a ...

  11. MRI of the Chest

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    Full Text Available ... food, or the environment, or if you have asthma. The contrast material most commonly used for an ... complete an MRI exam without moving. Whether a child requires sedation depends on the child's age, intellectual ...

  12. MRI of the Chest

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    Full Text Available ... The magnetic field is produced by passing an electric current through wire coils in most MRI units. Other coils, located in the machine and in some cases, placed around the part ...

  13. MRI of the Chest

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    Full Text Available ... copied to a CD or uploaded to a digital cloud server. MRI of the chest gives detailed ... sedative prior to your scheduled examination. Infants and young children usually require sedation or anesthesia to complete ...

  14. VISARTTM superconducting MRI system

    International Nuclear Information System (INIS)

    Usui, Yoshiyuki; Goro, Takehiko; Yamagata, Hitoshi.

    1995-01-01

    We have developed VISART TM , a 1.5 T high-field magnetic resonance imaging (MRI) system based on technology developed for both the FLEXART TM (0.5T) and MRT-200/GP (1.5T) systems as the first and second products, respectively, of a new series of MRI systems. VISART TM is a newly coined word combining VISion and state-of-the-ART. A higher power gradient system and new high-speed imaging techniques have been developed to meet the market demand for higher resolution images and shorter scan times. The product concepts of VISART TM are high image quality, high patient throughput, flexible clinical application, and ease of use, all of which are essential features for an MRI system in the high-field MRI market segment. (author)

  15. MRI of the Chest

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    Full Text Available ... may follow your regular daily routine and take food and medications as usual. Some MRI examinations may ... to iodine or x-ray contrast material, drugs, food, or the environment, or if you have asthma. ...

  16. Studying neuroanatomy using MRI.

    Science.gov (United States)

    Lerch, Jason P; van der Kouwe, André J W; Raznahan, Armin; Paus, Tomáš; Johansen-Berg, Heidi; Miller, Karla L; Smith, Stephen M; Fischl, Bruce; Sotiropoulos, Stamatios N

    2017-02-23

    The study of neuroanatomy using imaging enables key insights into how our brains function, are shaped by genes and environment, and change with development, aging and disease. Developments in MRI acquisition, image processing and data modeling have been key to these advances. However, MRI provides an indirect measurement of the biological signals we aim to investigate. Thus, artifacts and key questions of correct interpretation can confound the readouts provided by anatomical MRI. In this review we provide an overview of the methods for measuring macro- and mesoscopic structure and for inferring microstructural properties; we also describe key artifacts and confounds that can lead to incorrect conclusions. Ultimately, we believe that, although methods need to improve and caution is required in interpretation, structural MRI continues to have great promise in furthering our understanding of how the brain works.

  17. MRI of the Chest

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    Full Text Available ... any recent surgeries. Some conditions, such as severe kidney disease, may prevent you from being given gadolinium ... an MRI. If you have a history of kidney disease or liver transplant, it will be necessary ...

  18. MRI of the Chest

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    Full Text Available ... your regular medications as usual. Leave jewelry at home and wear loose, comfortable clothing. You may be ... Jewelry and other accessories should be left at home, if possible, or removed prior to the MRI ...

  19. MRI of the Chest

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    Full Text Available ... MRI. If you have claustrophobia (fear of enclosed spaces) or anxiety, you may want to ask your ... there is any question of their presence, an x-ray may be taken to detect and identify ...

  20. MRI of the Chest

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    Full Text Available ... tissue and fluid, known as edema . MRI typically costs more and may take more time to perform ... accredited facilities database . This website does not provide cost information. The costs for specific medical imaging tests, ...

  1. Towards MRI microarrays.

    Science.gov (United States)

    Hall, Andrew; Mundell, Victoria J; Blanco-Andujar, Cristina; Bencsik, Martin; McHale, Glen; Newton, Michael I; Cave, Gareth W V

    2010-04-14

    Superparamagnetic iron oxide nanometre scale particles have been utilised as contrast agents to image staked target binding oligonucleotide arrays using MRI to correlate the signal intensity and T(2)* relaxation times in different NMR fluids.

  2. MRI of the Chest

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    Full Text Available ... Thus, the child remains motionless allowing for good quality images. Jewelry and other accessories should be left ... claustrophobia. Newer open MRI units provide very high quality images for many types of exams. Older open ...

  3. MRI of the Chest

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    Full Text Available ... pocket knives and eyeglasses body piercings In most cases, an MRI exam is safe for patients with ... exam and bring it to your exam in case the radiologist or technologist has any questions. Some ...

  4. MRI of the Chest

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    Full Text Available ... contrast for an MRI. If you have a history of kidney disease or liver transplant, it will ... data suggest that it is safe to continue breastfeeding after receiving intravenous contrast. For further information please ...

  5. MRI of the Chest

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    Full Text Available ... used in tattoos may contain iron and could heat up during an MRI scan, but this is ... from the contrast material, including nausea, headache and pain at the site of injection. Similarly, patients are ...

  6. MRI of the Chest

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    Full Text Available ... MRI scanners are air-conditioned and well-lit. Music may be played through the headphones to help ... contrast material in patients with very poor kidney function. Careful assessment of kidney function before considering a ...

  7. MRI of the Chest

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    Full Text Available ... used in tattoos may contain iron and could heat up during an MRI scan, but this is ... preferred imaging test. MR imaging can assess blood flow without risking the side effects of conventional (catheter) ...

  8. MRI of the Chest

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    Full Text Available ... as severe kidney disease, may prevent you from being given gadolinium contrast for an MRI. If you ... can watch a movie while the scan is being performed. Thus, the child remains motionless allowing for ...

  9. MRI of the Chest

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    Full Text Available ... it is useful to bring that to the attention of the scheduler before the exam and bring ... bore which can be more comfortable for larger size patients or patients with claustrophobia. Other MRI machines ...

  10. MRI in osteochondrosis dissecans

    Energy Technology Data Exchange (ETDEWEB)

    Lehner, K.; Heuck, A.; Rodammer, G.; Raff, W.; Haller, W.

    1987-08-01

    The osseous manifestations of osteochondrosis dissecans are well demonstrated by conventional and computerised tomography. Beyond that, magnetic resonance imaging (MRI) is effective in evaluating the vitality and loosening of an osseous dissecate. Subchondral cavities and cartilaginous defects are detected with high acccuracy. Further, MRI seems to be a useful method in childhood to differentiate a variant irregularity of the osseous articular surface from definite osteochondrosis dissecans.

  11. MRI assessment program

    International Nuclear Information System (INIS)

    1987-09-01

    The MRI Assessment Program involves installation and operation of five MRI units in Australian public hospitals and the evaluation at each unit of the cost and efficacy of the technology over a period of two years. This first report in a series presents preliminary usage and cost data for the year to 30 June 1987 as well as describing the background and the data set. 6 figs., tabs

  12. Functional MRI of the patellofemoral joint: comparison of ultrafast MRI, motion-triggered cine MRI and static MRI

    Energy Technology Data Exchange (ETDEWEB)

    Muhle, C. [Klinik fuer Radiologische Diagnostik, Univ. Kiel (Germany); Brossmann, J. [Klinik fuer Radiologische Diagnostik, Univ. Kiel (Germany); Melchert, U.H. [Klinik fuer Radiologische Diagnostik, Univ. Kiel (Germany); Schroeder, C. [Radiologische Abt., Universitaets-Kinderklinik, Christian-Albrechts-Universitaet, Kiel (Germany); Boer, R. de [Philips Medical Systems, Best (Netherlands); Spielmann, R.P. [Klinik fuer Radiologische Diagnostik, Univ. Kiel (Germany); Heller, M. [Klinik fuer Radiologische Diagnostik, Univ. Kiel (Germany)

    1995-12-31

    To evaluate the feasibility and usefulness of ultrafast MRI (u), patellar tracking from 30 of flexion to knee extension (0 ) was analysed and compared with motion-triggered cine MRI (m) and a static MRI technique (s). The different imaging methods were compared in respect of the patellofemoral relationship, the examination time and image quality. Eight healthy subjects and four patients (in total 18 joints) with patellar subluxation or luxation were examined. Significant differences between the static MRI series without quadriceps contraction and the functional MRI studies (motion-triggered cine MRI and ultrafast MRI) were found for the patellar tilt angle. In the dynamic joint studies there was no statistical difference of the regression coefficients between the motion-triggered cine MRI studies and the ultrafast MRI studies. The findings of the functional MRI studies compared with the static MRI images were significantly different for the lateralisation of the patella, expressed by the lateral patellar displacement and bisect offset. No significant differences in patellar lateralisation were found between motion-triggered cine MRI and ultrafast MRI. Ultrafast MRI was superior to motion-triggered cine MRI in terms of the reduction in imaging time and improvement of the image quality. (orig.)

  13. Functional MRI of the patellofemoral joint: comparison of ultrafast MRI, motion-triggered cine MRI and static MRI

    International Nuclear Information System (INIS)

    Muhle, C.; Brossmann, J.; Melchert, U.H.; Schroeder, C.; Boer, R. de; Spielmann, R.P.; Heller, M.

    1995-01-01

    To evaluate the feasibility and usefulness of ultrafast MRI (u), patellar tracking from 30 of flexion to knee extension (0 ) was analysed and compared with motion-triggered cine MRI (m) and a static MRI technique (s). The different imaging methods were compared in respect of the patellofemoral relationship, the examination time and image quality. Eight healthy subjects and four patients (in total 18 joints) with patellar subluxation or luxation were examined. Significant differences between the static MRI series without quadriceps contraction and the functional MRI studies (motion-triggered cine MRI and ultrafast MRI) were found for the patellar tilt angle. In the dynamic joint studies there was no statistical difference of the regression coefficients between the motion-triggered cine MRI studies and the ultrafast MRI studies. The findings of the functional MRI studies compared with the static MRI images were significantly different for the lateralisation of the patella, expressed by the lateral patellar displacement and bisect offset. No significant differences in patellar lateralisation were found between motion-triggered cine MRI and ultrafast MRI. Ultrafast MRI was superior to motion-triggered cine MRI in terms of the reduction in imaging time and improvement of the image quality. (orig.)

  14. Nano-network with dual temperature and pH responsiveness based on copolymers of 2-hydroxyethyl methacrylate with 3,9-divinyl-2,4,8,10-tetraoxaspiro[5.5]-undecane

    International Nuclear Information System (INIS)

    Chiriac, Aurica P.; Nita, Loredana E.; Nistor, Manuela T.

    2011-01-01

    This study refers to the synthesis of a nano-network with dual temperature and pH responsiveness based on the 2-hydroxyethyl methacrylate (HEMA) copolymers with a comonomer with spiroacetal moiety and crosslinking capacity, namely 3,9-divinyl-2,4,8,10-tetraoxaspiro[5.5]-undecane (U). The copolymers were synthesized by radical emulsion polymerization, using 4,4′-azobis(cyanopentanoic acid) as initiator, in the presence of sodium lauryl sulfate as tensioactive agent and poly(vinyl alcohol) as protective colloid. Three copolymer variants were taken into study resulted from the different ratio between the comonomers (HEMA/U), which was about 98/2, 95/5, and 90/10, respectively. The copolymers were characterized by FTIR and thermal analysis. The copolymers sensitivity was evidenced by studying the evolution of the hydrodynamic radius and zeta potential of the polymeric particles as a function of pH. Thus, the particles size increases with the comonomer amount, from 193 nm in case of the homopolymer up to 253 nm for the copolymer with maximum content of the comonomer (10%). The increase of the particle hydrodynamic radius with the growth of temperature was also put into evidence.Graphical Abstract

  15. Nano-network with dual temperature and pH responsiveness based on copolymers of 2-hydroxyethyl methacrylate with 3,9-divinyl-2,4,8,10-tetraoxaspiro[5.5]-undecane

    Science.gov (United States)

    Chiriac, Aurica P.; Nita, Loredana E.; Nistor, Manuela T.

    2011-12-01

    This study refers to the synthesis of a nano-network with dual temperature and pH responsiveness based on the 2-hydroxyethyl methacrylate (HEMA) copolymers with a comonomer with spiroacetal moiety and crosslinking capacity, namely 3,9-divinyl-2,4,8,10-tetraoxaspiro[5.5]-undecane (U). The copolymers were synthesized by radical emulsion polymerization, using 4,4'-azobis(cyanopentanoic acid) as initiator, in the presence of sodium lauryl sulfate as tensioactive agent and poly(vinyl alcohol) as protective colloid. Three copolymer variants were taken into study resulted from the different ratio between the comonomers (HEMA/U), which was about 98/2, 95/5, and 90/10, respectively. The copolymers were characterized by FTIR and thermal analysis. The copolymers sensitivity was evidenced by studying the evolution of the hydrodynamic radius and zeta potential of the polymeric particles as a function of pH. Thus, the particles size increases with the comonomer amount, from 193 nm in case of the homopolymer up to 253 nm for the copolymer with maximum content of the comonomer (10%). The increase of the particle hydrodynamic radius with the growth of temperature was also put into evidence.

  16. Cine MRI of dissecting aneurysm

    International Nuclear Information System (INIS)

    Takaki, Hajime

    1991-01-01

    Cine MRI was performed in 25 cases of aortic dissection and comparative study among cine MRI, spin-echo static MRI, contrast-enhanced CT and intravenous digital subtraction angiography (IVDSA) was made. Cine MRI accurately detected aortic dissection. It was most accurate among various diagnostic methods in demonstration of entry site of dissection. Take-off of renal artery and its relation to true and false channels was also accurately demonstrated by cine MRI. The above results suggest that cine MRI can be an important diagnostic modality with almost equal diagnostic quality to those of conventional angiography. However, further technical improvement to shorten the imaging time seems necessary to replace angiography. (author)

  17. Combined PET/MRI

    DEFF Research Database (Denmark)

    Bailey, D L; Pichler, B J; Gückel, B

    2018-01-01

    The 6th annual meeting to address key issues in positron emission tomography (PET)/magnetic resonance imaging (MRI) was held again in Tübingen, Germany, from March 27 to 29, 2017. Over three days of invited plenary lectures, round table discussions and dialogue board deliberations, participants c...... of response to pharmacological interventions and therapies. As such, PET/MRI is a key to advancing medicine and patient care.......The 6th annual meeting to address key issues in positron emission tomography (PET)/magnetic resonance imaging (MRI) was held again in Tübingen, Germany, from March 27 to 29, 2017. Over three days of invited plenary lectures, round table discussions and dialogue board deliberations, participants...... critically assessed the current state of PET/MRI, both clinically and as a research tool, and attempted to chart future directions. The meeting addressed the use of PET/MRI and workflows in oncology, neurosciences, infection, inflammation and chronic pain syndromes, as well as deeper discussions about how...

  18. MRI of the lung

    Energy Technology Data Exchange (ETDEWEB)

    Kauczor, Hans-Ulrich (ed.) [University Clinic Heidelberg (Germany). Diagnostic and Interventional Radiology

    2009-07-01

    For a long time, only chest X-ray and CT were used to image lung structure, while nuclear medicine was employed to assess lung function. During the past decade significant developments have been achieved in the field of magnetic resonance imaging (MRI), enabling MRI to enter the clinical arena of chest imaging. Standard protocols can now be implemented on up-to-date scanners, allowing MRI to be used as a first-line imaging modality for various lung diseases, including cystic fibrosis, pulmonary hypertension and even lung cancer. The diagnostic benefits stem from the ability of MRI to visualize changes in lung structure while simultaneously imaging different aspects of lung function, such as perfusion, respiratory motion, ventilation and gas exchange. On this basis, novel quantitative surrogates for lung function can be obtained. This book provides a comprehensive overview of how to use MRI for imaging of lung disease. Special emphasis is placed on benign diseases requiring regular monitoring, given that it is patients with these diseases who derive the greatest benefit from the avoidance of ionizing radiation. (orig.)

  19. Diffusion, confusion and functional MRI

    International Nuclear Information System (INIS)

    Le Bihan, Denis

    2012-01-01

    Diffusion MRI has been introduced in 1985 and has had a very successful life on its own. While it has become a standard for imaging stroke and white matter disorders, the borders between diffusion MRI and the general field of fMRI have always remained fuzzy. First, diffusion MRI has been used to obtain images of brain function, based on the idea that diffusion MRI could also be made sensitive to blood flow, through the intra-voxel incoherent motion (IVIM) concept. Second, the IVIM concept helped better understand the contribution from different vasculature components to the BOLD fMRI signal. Third, it has been shown recently that a genuine fMRI signal can be obtained with diffusion MRI. This 'DfMRI' signal is notably different from the BOLD fMRI signal, especially for its much faster response to brain activation both at onset and offset, which points out to structural changes in the neural tissues, perhaps such as cell swelling, occurring in activated neural tissue. This short article reviews the major steps which have paved the way for this exciting development, underlying how technical progress with MRI equipment has each time been instrumental to expand the horizon of diffusion MRI toward the field of fMRI. (authors)

  20. MRI for myocarditis

    International Nuclear Information System (INIS)

    Gutberlet, M.; Luecke, C.; Krieghoff, C.; Hildebrand, L.; Steiner, J.; Adam, J.; Grotthoff, M.; Lehmkuhl, L.; Lurz, P.; Eitel, I.; Thiele, H.

    2013-01-01

    Cardiovascular magnetic resonance imaging (CMRI) has become the primary tool for the non-invasive assessment in patients with suspected myocarditis, especially after exclusion of acute coronary syndrome (ACS) for the differential diagnosis. Various MRI parameters are available which have different accuracies. Volumetric and functional ventricular assessment and the occurrence of pericardial effusion alone demonstrate only a poor sensitivity and specificity. The calculation of the T2-ratio (edema assessment), the early or global relative myocardial enhancement (gRE) and the late gadolinium enhancement (LGE), which represents irreversibly injured myocardium, are more specific parameters. All MRI parameters demonstrate the best accuracy in infarct-like acute myocarditis, whereas in chronic myocarditis sensitivity and specificity are less accurate. Therefore, a multisequential (at least two out of three parameters are positive) approach is recommended. The assessment of the value of newer, more quantitative MRI sequences, such as T1 and T2-mapping is still under investigation. (orig.) [de

  1. MRI in gout

    International Nuclear Information System (INIS)

    Seidl, G.; Ullrich, R.; Trattnig, S.; Dominkus, M.; Morscher, M.; Aringer, M.; Imhof, H.

    1996-01-01

    The appearance of gouty tophus in magnetic resonance imaging (MRI) is characteristic. On T1- and T2-weighted SE images, the signal intensity of tophaceous lesions is similar to that of muscles. According to the histology, T2-weighted SE images demonstrate extremely hyperintense signals, which reflect the high protein content in the amorpheous center of the tophus. The microscopic urate crystals deposited there have no MRI signal and are of no further diagnostic impact. Vascularized granulation tissue surrounding the tophus center enhance after intervenous application of contrast agents (Gadolinium). The inflammed tophus is associated with local edema, causing high signal intensity. MRI is superior to plain radiography for early detection of intraosseous tophi. Involvement of anatomical structures such as ligaments and tendons can be evaluated sufficiently. For peripheral joints, axial slice orientation is most helpful. (orig.) [de

  2. MRI of oriental cholangiohepatitis

    Energy Technology Data Exchange (ETDEWEB)

    Wani, N.A., E-mail: ahmad77chinar@gmail.co [Department of Radiodiagnosis and Imaging, Sher-I-Kashmir Institute of Medical Sciences (SKIMS), Srinagar (India); Robbani, I.; Kosar, T. [Department of Radiodiagnosis and Imaging, Sher-I-Kashmir Institute of Medical Sciences (SKIMS), Srinagar (India)

    2011-02-15

    Oriental cholangiohepatitis (OCH) also called recurrent pyogenic cholangitis is characterized by intrahepatic duct calculi, strictures, and recurrent infections. In turn cholangitis can result in multiple hepatic abscesses, further biliary strictures, and in severe cases, progressive hepatic parenchymal destruction, cirrhosis, and portal hypertension. Magnetic resonance cholangiopancreatography (MRCP) and conventional T1-weighted (T1 W) and T2-weighted (T2 W) magnetic resonance imaging (MRI) findings have been described in patients with OCH. MRCP findings include duct dilation, strictures, and calculi. MRCP can help to localize the diseased ducts and determine the severity of involvement. T1 and T2 W sequences reveal the parenchymal changes of atrophy, abscess formation, and portal hypertension in addition to calculi. Post-treatment changes are also well depicted using MRI. Comprehensive, non-invasive assessment is achieved by using conventional MRI and MRCP in OCH providing a roadmap for endoscopic or surgical management.

  3. Contrast agents for MRI

    International Nuclear Information System (INIS)

    Bonnemain, B.

    1994-01-01

    Contrast agents MRI (Magnetic Resonance Imaging) have been developed to improve the diagnostic information obtained by this technic. They mainly interact on T1 and T2 parameters and increase consequently normal to abnormal tissues contrast. The paramagnetic agents which mainly act on longitudinal relaxation rate (T1) are gadolinium complexes for which stability is the main parameter to avoid any release of free gadolinium. The superparamagnetic agents that decrease signal intensity by an effect on transversal relaxation rate (T2) are developed for liver, digestive and lymph node imaging. Many area of research are now opened for optimal use of present and future contrast agents in MRI. (author). 28 refs., 4 tabs

  4. MRI of vaginal conditions

    International Nuclear Information System (INIS)

    Lopez, C.; Balogun, M.; Ganesan, R.; Olliff, J.F.

    2005-01-01

    Magnetic resonance imaging (MRI) has become an important part of the assessment of suspected vaginal pathology. This pictorial review demonstrates the MRI features and some of the histopathological findings of a variety of vaginal conditions. These may be congenital (total vaginal agenesis, partial vaginal agenesis, longitudinal vaginal septum, transverse vaginal septum), benign (Bartholin's cyst, diffuse vaginal inflammation, invasive endometriosis, ureterovaginal fistula, post-surgical appearances with the formation of a neovagina and adhesions) or malignant, usually due to extension or recurrence from another pelvic malignancy. In this paper, examples of the above are described and illustrated together with examples of the much rarer primary vaginal malignancies

  5. MRI of vaginal conditions

    Energy Technology Data Exchange (ETDEWEB)

    Lopez, C. [Department of Radiology, Birmingham Women' s Hospital, Birmingham (United Kingdom)]. E-mail: carolina.lopez@bwhct.nhs.uk; Balogun, M. [Department of Radiology, Birmingham Women' s Hospital, Birmingham (United Kingdom); Ganesan, R. [Department of Histopathology, Birmingham Women' s Hospital, Birmingham (United Kingdom); Olliff, J.F. [University Hospital Birmingham, Birmingham (United Kingdom)

    2005-06-01

    Magnetic resonance imaging (MRI) has become an important part of the assessment of suspected vaginal pathology. This pictorial review demonstrates the MRI features and some of the histopathological findings of a variety of vaginal conditions. These may be congenital (total vaginal agenesis, partial vaginal agenesis, longitudinal vaginal septum, transverse vaginal septum), benign (Bartholin's cyst, diffuse vaginal inflammation, invasive endometriosis, ureterovaginal fistula, post-surgical appearances with the formation of a neovagina and adhesions) or malignant, usually due to extension or recurrence from another pelvic malignancy. In this paper, examples of the above are described and illustrated together with examples of the much rarer primary vaginal malignancies.

  6. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... to a CD or uploaded to a digital cloud server. Currently, MRI is the most sensitive imaging ... over time. top of page What are the benefits vs. risks? Benefits MRI is a noninvasive imaging ...

  7. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... metallic items, which can distort MRI images removable dental work pens, pocket knives and eyeglasses body piercings In most cases, an MRI exam is safe for patients with metal implants, except for a few types. ...

  8. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... interfere with the magnetic field of the MRI unit, metal and electronic items are not allowed in ... does the equipment look like? The traditional MRI unit is a large cylinder-shaped tube surrounded by ...

  9. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... items, which can distort MRI images removable dental work pens, pocket knives and eyeglasses body piercings In most cases, an MRI exam is safe for patients with metal implants, except for a ...

  10. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... metallic items, which can distort MRI images removable dental work pens, pocket knives and eyeglasses body piercings ... tomography (CT) scans, MRI does not utilize ionizing radiation. Instead, radiofrequency pulses re-align hydrogen atoms that ...

  11. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... women should not have this exam in the first three to four months of pregnancy unless the ... not to have an MRI exam during the first trimester unless medically necessary. MRI may not always ...

  12. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... room. In addition to affecting the MRI images, these objects can become projectiles within the MRI scanner ... may cause you and/or others nearby harm. These items include: jewelry, watches, credit cards and hearing ...

  13. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... conditions. MRI uses a powerful magnetic field, radio frequency pulses and a computer to produce detailed pictures ... may follow your regular daily routine and take food and medications as usual. Some MRI examinations may ...

  14. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... contrast for an MRI. If you have a history of kidney disease or liver transplant, it will ... claustrophobia. Newer open MRI units provide very high quality images for many types of exams. Older open ...

  15. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... are the limitations of MRI of the Head? What is MRI of the Head? Magnetic resonance imaging ( ... brain) in routine clinical practice. top of page What are some common uses of the procedure? MR ...

  16. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... is done because a potential abnormality needs further evaluation with additional views or a special imaging technique. ... MRI an invaluable tool in early diagnosis and evaluation of many conditions, including tumors. MRI enables the ...

  17. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... MRI scanners are air-conditioned and well-lit. Music may be played through the headphones to help ... used in MRI exams is less likely to produce an allergic reaction than the iodine-based contrast ...

  18. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... or headphones during the exam. MRI scanners are air-conditioned and well-lit. Music may be played ... the limitations of MRI of the Head? High-quality images are assured only if you are able ...

  19. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... used in tattoos may contain iron and could heat up during an MRI scan, but this is ... imaging based on the electrical activity of the heart, such as electrocardiography (EKG). MRI generally is not ...

  20. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... medically necessary. MRI may not always distinguish between cancer tissue and fluid, known as edema . MRI typically ... Brain Tumors Radiation Therapy for Head and Neck Cancer Others : American Stroke Association National Stroke Association top ...

  1. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... MRI scanners are air-conditioned and well-lit. Music may be played through the headphones to help ... tissue and fluid, known as edema . MRI typically costs more and may take more time to perform ...

  2. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... top of page What are the benefits vs. risks? Benefits MRI is a noninvasive imaging technique that ... than 30 minutes from the onset of symptoms. Risks The MRI examination poses almost no risk to ...

  3. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... claustrophobia. Newer open MRI units provide very high quality images for many types of exams. Older open MRI units may not provide this same image quality. Certain types of exams cannot be performed using ...

  4. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... MRI examination poses almost no risk to the average patient when appropriate safety guidelines are followed. If ... tissue and fluid, known as edema . MRI typically costs more and may take more time to perform ...

  5. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... as severe kidney disease, may prevent you from being given gadolinium contrast for an MRI. If you ... of time after placement (usually six weeks) before being safe for MRI examinations. Examples include but are ...

  6. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... This detail makes MRI an invaluable tool in early diagnosis and evaluation of many conditions, including tumors. ... information. MRI can detect stroke at a very early stage by mapping the motion of water molecules ...

  7. Quality assurance in functional MRI

    DEFF Research Database (Denmark)

    Liu, Thomas T; Glover, Gary H; Mueller, Bryon A

    2015-01-01

    Over the past 20 years, functional magnetic resonance imaging (fMRI) has ben- efited greatly from improvements in MRI hardware and software. At the same time, fMRI researchers have pushed the technical limits of MRI systems and greatly in- fluenced the development of state-of-the-art systems...... consistent data throughout the course of a study, and consistent stability across time and sites is needed to allow data from different time periods or acquisition sites to be optimally integrated....

  8. Less Confusion in Diffusion MRI

    NARCIS (Netherlands)

    Tax, CMW

    2016-01-01

    With its unique ability to investigate tissue architecture and microstructure in vivo, diffusion MRI (dMRI) has gained tremendous interest and the society has been continuously triggered to develop novel dMRI image analysis approaches. With the overwhelming amount of strategies currently available

  9. MRI in subacute combined degeneration

    International Nuclear Information System (INIS)

    Murata, S.; Naritomi, H.; Sawada, T.

    1994-01-01

    Neuropathological studies show the main lesions to be in the posterior and lateral columns. Recent progress in MRI has made it possible to clarify the lesions of many neutrological diseases. However, there has only been one report of the lesions of SCD shown definitely on MRI. We report a typical case of the disease, with lesions shown clearly on MRI. (orig./MG)

  10. MRI of the Chest

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    Full Text Available ... to prepare your child for the sedation or anesthesia. Alternatively, certain pediatric facilities have child life personnel who can work with younger children to help avoid the need for sedation or anesthesia. They prepare the children for MRI by showing ...

  11. Combined PET/MRI

    DEFF Research Database (Denmark)

    Bailey, D. L.; Pichler, B. J.; Gückel, B.

    2015-01-01

    This paper summarises key themes and discussions from the 4th international workshop dedicated to the advancement of the technical, scientific and clinical applications of combined positron emission tomography (PET)/magnetic resonance imaging (MRI) systems that was held in Tübingen, Germany, from...

  12. MRI of the Chest

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    Full Text Available ... types of clips used for brain aneurysms some types of metal coils placed within blood vessels nearly all cardiac defibrillators and pacemakers You ... a preferred imaging test. MR imaging can assess blood flow without ... the opening of certain types of MRI machines. The presence of an implant ...

  13. MRI of the Chest

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    Full Text Available ... procedure work? How is the procedure performed? What will I experience during and after the procedure? Who interprets the results and how do I get them? What are the benefits vs. risks? What are the limitations of MRI ...

  14. MRI of the Chest

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    Full Text Available ... or anesthesia. Alternatively, certain pediatric facilities have child life personnel who can work with younger children to help avoid the need ... MRI units may not provide this same image quality. Certain types of exams cannot be ... work? Unlike conventional x-ray examinations and computed tomography ( ...

  15. MRI of the Chest

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    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician Resources Professions Site Index A-Z Magnetic Resonance Imaging (MRI) - ...

  16. MRI of the Chest

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    Full Text Available ... have allergies of any kind, such as an allergy to iodine or x-ray contrast material, drugs, food, or the environment, or if you have asthma. The contrast material most commonly used for an MRI exam contains a metal ... in patients with iodine contrast allergy. It is far less common for a patient ...

  17. Acute epiglottitis: MRI

    International Nuclear Information System (INIS)

    Ozanne, A.; Marsot-Dupuch, K.; Ducreux, D.; Lasjaunias, P.; Meyer, B.

    2004-01-01

    We report the MRI findings in an adult with epiglottitis. There was thickening of the epiglottis and left aryepiglottic fold. Management of this life-threatening condition requires imaging only when the diagnosis is uncertain or when an abscess or other complication is suspected. (orig.)

  18. MRI of the Chest

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    Full Text Available ... a mild sedative prior to your scheduled examination. Infants and young children usually require sedation or anesthesia to complete an MRI exam without moving. Whether a child requires sedation depends on the child's age, intellectual development and the type of exam. Moderate and conscious ...

  19. Hippocampal malrotation: MRI findings

    International Nuclear Information System (INIS)

    Yanez, Paulina; Martinez, Adriana; Romero, Carlos; Lopez, Miriam; Zaffaroni, Alejandra; Lopez, Adriana

    2001-01-01

    Purpose: To demonstrate the common features of hippocampus malrotation in patients with epilepsy by volumetric and high-resolution MRI. Material and methods: MRI study was performed in 5 patients (2 females and 3 males) ages ranged between 6-41 years (average: 25 years), all of them with epilepsy diagnosis. MRI was performed with a 1.5 T (GE Signa). The epilepsy protocol include sagittal T1, axial T1 and T2, coronal FLAIR, coronal T2 (high-resolution) and volumetric 3D SPGR IR 1.5 mm thick sequences. Results: The common features found in all patients were: a) Incomplete inversion and round configuration of the hippocampus; b) Unilateral affectation; c) Variable affectation of the hippocampus; d) Normal signal intensity; e) Modification of the inner structure of the hippocampus; f) Abnormal angularity of the collateral sulcus; g) Abnormal position and size of the fornix; h) Normal size of the temporal lobe; and i) Enlargement of the temporal horn with particular configuration. Conclusion: Hippocampus malrotation is a malformation that should be included in the differential diagnosis of the epilepsy patients. MRI provides accurate information for the diagnosis. (author)

  20. MRI of the Chest

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    Full Text Available ... Imaging (MRI) - Chest Sponsored by Please note RadiologyInfo.org is not a medical facility. Please contact your ... links: For the convenience of our users, RadiologyInfo .org provides links to relevant websites. RadiologyInfo.org , ACR ...

  1. MRI of the Chest

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    Full Text Available ... Whether a child requires sedation depends on the child's age, intellectual development and the type of exam. Moderate and conscious ... intercom. Many MRI centers allow a friend or parent to stay in the room as long as they are also ... will be given appropriately sized earplugs or headphones ...

  2. MRI of the Chest

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    Full Text Available ... of which shows a thin slice of the body. The images can then be studied from different angles by ... bear denotes child-specific content. Related Articles and Media MR ... Images related to Magnetic Resonance Imaging (MRI) - Chest Sponsored ...

  3. MRI of the Chest

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    Full Text Available ... about pregnancy and MRI. If you have claustrophobia (fear of enclosed spaces) or anxiety, you may want to ask your physician for a prescription for a mild sedative prior to your scheduled examination. Infants and young children usually require sedation or anesthesia to complete an ...

  4. MRI of the Chest

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    Full Text Available ... to have an allergy to a gadolinium-based contrast agent used for MRI than the iodine-containing contrast ... more information on adverse reactions to gadolinium-based contrast agents, please consult the ACR Manual on Contrast Media . ...

  5. MRI of the Chest

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    Full Text Available ... which they come. The MR scanner captures this energy and creates a picture of the tissues scanned based on this information. The magnetic field is produced by passing an electric current through wire coils in most MRI units. ...

  6. Fetal MRI; Fetales MRT

    Energy Technology Data Exchange (ETDEWEB)

    Blondin, D. [Inst. fuer Diagn. Radiologie, Uniklinikum Duesseldorf (Germany); Turowski, B. [Inst. fuer Diagn. Radiologie, Neuroradiologie, Uniklinikum Duesseldorf (Germany); Schaper, J. [Inst. fuer Diagn. Radiologie, Kinderradiologie, Uniklinikum Duesseldorf (Germany)

    2007-02-15

    Ultrasonography is the method of choice for prenatal malformation screening, but it does not always provide sufficient information for correct diagnosis or adequate abnormality evaluation. Fetal MRI is increasingly being used to complete sonographic findings. It was initially used for evaluation of cerebral abnormalities but is increasingly being applied to other fetal areas. In vivo investigation of fetal brain maturation has been enhanced by MRI. An adequate analysis of fetal chest and abdomen can be achieved with fast T2-, T1-weighted and diffusion-weighted imaging (DWI). The advantages include the great field of view and the excellent soft tissue contrast. This allows correct diagnosis of congenital diaphragmatic hernia and evaluation of the consequences on pulmonary growth. Other pulmonary malformations, such as cystic adenomatoid malformation, sequestration and brochogenic cysts, can also be easily identified. Renal position can be quickly determined using DWI sequences and renal agenesia can be easily diagnosed with only one sequence. Prenatal MRI is virtually as effective as postnatal examination, dispenses with transport of a potentially very ill newborn, and provides logistic advantages. Therefore, prenatal MRI is useful for adequate postnatal treatment of newborns with malformations. (orig.)

  7. MRI of the Chest

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    Full Text Available ... contrast for an MRI. If you have a history of kidney disease or liver transplant, it will be necessary to perform a blood test to determine whether the kidneys are functioning adequately. Women should always inform their physician or technologist if ...

  8. MRI of the Chest

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    Full Text Available ... complete an MRI exam without moving. Whether a child requires sedation depends on the child's age, intellectual development and the type of exam. ... should be available during the exam for your child's safety. You will be given special instructions for ...

  9. MRI in suspected appendicitis

    NARCIS (Netherlands)

    Leeuwenburgh, M.M.N.

    2014-01-01

    Dit proefschrift richt zich op de optimalisatie van beeldvormende diagnostiek bij patiënten met een klinische verdenking op appendicitis, waarbij het gebruik van ‘magnetic resonance imaging’ (MRI) wordt verkend. Het proefschrift omvat de resultaten van de OPTIMAP-studie (OPTimisation of IMaging

  10. MRI of the cardiomyopathies

    International Nuclear Information System (INIS)

    Di Cesare, Ernesto

    2001-01-01

    We examined the potentialities of Magnetic resonance imaging (MRI) in the evaluation of the main cardiomyopathies: hypertrophic, dilated, restrictive and arrhythmogenic right ventricular. The hypertrophic cardiomyopathy is generally adequately investigated by echocardiography, that well defines the myocardial thickening and the obstruction of the left ventricular output. However, by echocardiography we still have difficulties in the evaluation of the apex of the left ventricle and the right ventricle involvement. MRI provides a complete evaluation of the heart with a clear evidence also of the echocardiographic dark zones by means of a clear evidence of the apex of the right ventricle. The dilated form is also well investigated by MRI that provides a clear evaluation of the volumes, mass and ejection fraction by means of the 3D analysis including conditions of the ventricular remodelling. Moreover, this technique helps in the differential diagnosis of acute myocarditis. In the acute phase of myocarditis (first 2 weeks), in fact, the myocardium produces high signal intensity on the T2 weighted sequences due to the presence of oedema. The third form of cardiomyopathy is the restrictive one, characterised by reduced diastolic filling and diastolic volume, normality of the systolic function and parietal thickness, interstitial fibrosis and enlargement of both atria. The mean potentiality of MRI is related to the differential diagnosis with constrictive pericarditis. Only in the former, the pericardium appears irregularly thickened with areas exceeding 4 mm of pericardial thickness. Finally, the right ventricular arrhythmogenic cardiomyopathy represents the main indication to MRI evaluation. With this imaging modality we are can obtain a clear morpho-functional evaluation of the right ventricle and distinguish the intramyocardial adipose substitution characterised by areas of high signal in the myocardium

  11. MRI of cardiovascular malformations

    Energy Technology Data Exchange (ETDEWEB)

    Kastler, Bruno [Centre Hospitalier Univ. Jean Minjoz, Besancon (France); Universite de Franche-Comte, Besancon (FR). Lab. I4S (Health, Innovation, Intervention, Imaging, Engineering); Centre Hospitalier Sherbrooke Univ., PQ (Canada). Dept. of Radiology

    2011-07-01

    MRI is a non-invasive and non-ionizing imaging modality that is perfectly suited for the diagnosis and follow-up of both pediatric and adult congenital heart disease. It provides a large field of view and has the unique ability to depict complex cardiac and vascular anatomy and to measure cardiac function and flow within one examination. MRI is the ideal complement to echocardiography whenever the information provided by the latter is limited. This book has been conceived as a self-teaching manual that will assist qualified radiologists, cardiologists, and pediatricians, as well as those in training. It is richly illustrated with numerous images and drawings that cover all usual and most unusual anomalies. The principal author, Professor Bruno Kastler, is head of radiology at Besancon University Hospital, France and is board certified in both radiology and cardiology. (orig.)

  12. MRI of cardiovascular malformations

    International Nuclear Information System (INIS)

    Kastler, Bruno; Universite de Franche-Comte, Besancon; Centre Hospitalier Sherbrooke Univ., PQ

    2011-01-01

    MRI is a non-invasive and non-ionizing imaging modality that is perfectly suited for the diagnosis and follow-up of both pediatric and adult congenital heart disease. It provides a large field of view and has the unique ability to depict complex cardiac and vascular anatomy and to measure cardiac function and flow within one examination. MRI is the ideal complement to echocardiography whenever the information provided by the latter is limited. This book has been conceived as a self-teaching manual that will assist qualified radiologists, cardiologists, and pediatricians, as well as those in training. It is richly illustrated with numerous images and drawings that cover all usual and most unusual anomalies. The principal author, Professor Bruno Kastler, is head of radiology at Besancon University Hospital, France and is board certified in both radiology and cardiology. (orig.)

  13. MRI of the shoulder

    Energy Technology Data Exchange (ETDEWEB)

    Vahlensieck, M.

    2000-02-01

    Shoulder imaging is one of the major applications in musculoskeletal MRI. In order to analyze the images it is important to keep informed about anatomical and pathological findings and publications. In this article MRI technique, anatomy and pathology is reviewed. Technical considerations about MR sequences and examination strategy are only shortly discussed with emphasis on turbo spin echo and short T1 inversion recovery imaging. Basic anatomy as well as recent findings, including macroscopic aspects of the supraspinatus fat pad, composition of the supraspinatus muscle belly, and variability of the glenohumeral ligaments or coracoid ligament, are presented. Basic pathological conditions are described in detail, e. g. instability particularly problems in differentiating the various subtypes of labral pathology. Rotator cuff diseases are elucidated with emphasis on some rarer entities such as subscapularis calcifying tendinitis, coracoid impingement, chronic bursitis producing the double-line sign, prominent coraco-acromial ligament and the impingement due to an inflamed os acromiale. (orig.)

  14. Boomerang sign on MRI.

    Science.gov (United States)

    Hirsch, Karen G; Hoesch, Robert E

    2012-06-01

    Altered mental status and more subtle cognitive and personality changes after traumatic brain injury (TBI) are pervasive problems in patients who survive initial injury. MRI is not necessarily part of the diagnostic evaluation of these patients. Case report with relevant image and review of the literature. Injury to the corpus callosum is commonly described in traumatic brain injury; however, extensive lesions in the splenium are not well described. This image shows an important pattern of brain injury and demonstrates a common clinical syndrome seen in patients with corpus callosum pathology. Injury to the splenium of the corpus callosum due to trauma may be extensive and can cause significant neurologic deficits. MRI is important in the diagnostic evaluation of patients with cognitive changes after TBI.

  15. MRI of the shoulder

    International Nuclear Information System (INIS)

    Vahlensieck, M.

    2000-01-01

    Shoulder imaging is one of the major applications in musculoskeletal MRI. In order to analyze the images it is important to keep informed about anatomical and pathological findings and publications. In this article MRI technique, anatomy and pathology is reviewed. Technical considerations about MR sequences and examination strategy are only shortly discussed with emphasis on turbo spin echo and short T1 inversion recovery imaging. Basic anatomy as well as recent findings, including macroscopic aspects of the supraspinatus fat pad, composition of the supraspinatus muscle belly, and variability of the glenohumeral ligaments or coracoid ligament, are presented. Basic pathological conditions are described in detail, e. g. instability particularly problems in differentiating the various subtypes of labral pathology. Rotator cuff diseases are elucidated with emphasis on some rarer entities such as subscapularis calcifying tendinitis, coracoid impingement, chronic bursitis producing the double-line sign, prominent coraco-acromial ligament and the impingement due to an inflamed os acromiale. (orig.)

  16. MRI: Imaging of stomach

    International Nuclear Information System (INIS)

    Lam, W. W. M; Lee, J. S. W.; Ho, G.

    2007-01-01

    Full text: The study is to determine the optimal MRI bowel preparation regime for visualization of the stomach anatomy, Eight healthy volunteers were asked to take water, 75% barium and blueberry juice. The image quality and tolerance of different stomach distension regime were evaluated. Blueberry juice gave the best distension, but the signal intensity was not very homogeneous. Taking into account the image quality, tolerability and adverse effects, it is concluded that water is the most desirable oral contrast for MR stomach imaging

  17. MRI anatomy of schizophrenia.

    Science.gov (United States)

    McCarley, R W; Wible, C G; Frumin, M; Hirayasu, Y; Levitt, J J; Fischer, I A; Shenton, M E

    1999-05-01

    Structural magnetic resonance imaging (MRI) data have provided much evidence in support of our current view that schizophrenia is a brain disorder with altered brain structure, and consequently involving more than a simple disturbance in neurotransmission. This review surveys 118 peer-reviewed studies with control group from 1987 to May 1998. Most studies (81%) do not find abnormalities of whole brain/intracranial contents, while lateral ventricle enlargement is reported in 77%, and third ventricle enlargement in 67%. The temporal lobe was the brain parenchymal region with the most consistently documented abnormalities. Volume decreases were found in 62% of 37 studies of whole temporal lobe, and in 81% of 16 studies of the superior temporal gyrus (and in 100% with gray matter separately evaluated). Fully 77% of the 30 studies of the medial temporal lobe reported volume reduction in one or more of its constituent structures (hippocampus, amygdala, parahippocampal gyrus). Despite evidence for frontal lobe functional abnormalities, structural MRI investigations less consistently found abnormalities, with 55% describing volume reduction. It may be that frontal lobe volume changes are small, and near the threshold for MRI detection. The parietal and occipital lobes were much less studied; about half of the studies showed positive findings. Most studies of cortical gray matter (86%) found volume reductions were not diffuse, but more pronounced in certain areas. About two thirds of the studies of subcortical structures of thalamus, corpus callosum and basal ganglia (which tend to increase volume with typical neuroleptics), show positive findings, as do almost all (91%) studies of cavum septi pellucidi (CSP). Most data were consistent with a developmental model, but growing evidence was compatible also with progressive, neurodegenerative features, suggesting a "two-hit" model of schizophrenia, for which a cellular hypothesis is discussed. The relationship of clinical

  18. MRI anatomy of schizophrenia

    OpenAIRE

    McCarley, Robert William; Wible, Cynthia Gayle; Frumin, Melissa; Hirayasu, Yoshio; Levitt, James Jonathan; Fischer, Iris A.; Shenton, Martha Elizabeth

    1999-01-01

    Structural magnetic resonance imaging (MRI) data have provided much evidence in support of our current view that schizophrenia is a brain disorder with altered brain structure, and consequently involving more than a simple disturbance in neurotransmission. This review surveys 118 peer–reviewed studies with control group from 1987 to May 1998. Most studies (81%) do not find abnormalities of whole brain/intracranial contents, while lateral ventricle enlargement is reported in 77%, and third ven...

  19. MRI in insulinomas

    International Nuclear Information System (INIS)

    Liessi, Guido; Pasquali, Claudio; Alfano D'Andrea, Alfonso; Pedrazzoli, Sergio; Scandellari, Cesare

    1992-01-01

    After establishing the diagnosis of an insulinoma, most surgeons prefer preoperative localization. Selective arteriography is usually considered the gold standard for this purpose. Recently, computed tomography (CT) and preoperative US have contended the role to angiography. MRI has been used in few cases of endocrine pancreatic tumors, and its role in this particular field has to be defined. Between November 1988-September 1990 7 adult patients who had undergone surgery were evaluated. Eight tumors were resected in 6 patients who were cured; in an 18-year-old woman surgical treatment was unsuccessful. Arterio-graphy, CT, preoperative US, MRI and intraoperative US detected 2, 6, 6, 5 and 6 tumors respectively. Two insulinomas (0.2 and 0.7 cm) were found at histologic examination in resected specimen. The ability of intra-operative US and careful surgical exploration to resolve more than 90 percent of cases makes the preoperative use of arteriography and CT questionable value. If further experience confirms these findings, US and MRI may suffice. (author). 13 refs.; 3 figs.; 1 tab

  20. MRI of symptomatic shoulders

    International Nuclear Information System (INIS)

    Kikukawa, Kenshi; Segata, Tateki; Kunitake, Katsuhiko; Morisawa, Keizo; Harada, Masataka; Hirano, Mako

    2004-01-01

    The purpose of this study was to determine the prevalence of cuff tear and acromioclavicular joint (ACJ) osteoarthrosis by magnetic resonance imaging (MRI) evaluation in symptomatic shoulders. MRI was performed on 124 shoulders in 115 patients whose age ranged from 16 to 83 years (average: 58.0 years). There were 74 men (79 shoulders) and 41 women (45 shoulders). The patients were divided into three groups according to age; A group (10 shoulders: 16-29 years), B group (43 shoulders: 30-59 years), and C group (71 shoulders: 60-83 years). Rotator cuff tears and ACJ osteoarthrosis were graded on scales 0 to 3 (normal, increased signal intensity, incomplete, complete), and 1 to 4 (none, mild, moderate, severe), respectively. There was a significant difference in the severity of the cuff tears and the ACJ osteoarthrosis with respect to age. Twenty percent of the shoulders were graded incomplete or complete cuff tears in group A, 88% in group B, and 93% in group C. No shoulders were graded moderate or severe ACJ changes in group A, 63% in group B, and 93% in group C. There was a definite correlation between the cuff tears and ACJ osteoarthrosis. MRI of the symptomatic shoulders indicated well correlation between the rotator cuff tears and ACJ osteoarthrosis. (author)

  1. MRI diagnosis of meningovascular neurosyphilis

    International Nuclear Information System (INIS)

    Chen Shuang; Qian Jianguo; Feng Xiaoyuan

    2005-01-01

    Objective: To evaluate the value and limitation of MRI in the diagnosis of meningovascular neurosyphilis. Methods: Five cases of neurosyphilis confirmed by clinical history/laboratory were examined with MRI (3 plain MRI, 2 enhanced MRI). The results of blood and CSF TPPA/RPR were positive and HIV was negative. Results: Abnormal signals were demonstrated in the temporal lobe in 3 cases, and infarction was revealed in the basal ganglion and periventricular white matter in another 2 cases. There was no marked contrast enhancement in the 2 cases. Conclusion: Meningovascular neurosyphilis has no characteristic features on MRI, but MRI is an effective method in delineating the size, range, and characters of neurosyphilis, and it is also an useful modality to follow-up after antibiotic therapy. (authors)

  2. Functional MRI of the kidneys

    OpenAIRE

    Zhang, Jeff L.; Rusinek, Henry; Chandarana, Hersh; Lee, Vivian S.

    2013-01-01

    Renal function is characterized by different physiologic aspects, including perfusion, glomerular filtration, interstitial diffusion and tissue oxygenation. MRI shows great promise in assessing these renal tissue characteristics noninvasively. The last decade has witnessed a dramatic progress in MRI techniques for renal function assessment. This article briefly describes relevant renal anatomy and physiology, reviews the applications of functional MRI techniques for the diagnosis of renal dis...

  3. MRI assessment program. Consensus statement on clinical efficacy of MRI

    International Nuclear Information System (INIS)

    1998-05-01

    This consensus statement is largely based on the experience gained at the MRI units at the four hospitals which have operated scanners in the MRI program. It reflects the considered opinion of the radiologists responsible for the MRI services at those hospitals. Account has also been taken of relevant overseas data. This collection of opinion relates particularly to comparison with other imaging modalities. The specific comments will require further consideration as technical developments with MRI become available, additional experience is gained with gadolinium contrast material and additional data are obtained on the influence of MRI on patient management. MRI, at present, is used either to improve diagnostic accuracy when other tests are negative or equivocal, when there is strong clinical suspicion of disease, or to improve surgical or other management planning when the diagnosis known. In some situations (eg syringomyelia, congenital spinal disease, posterior fossa/cerebello-pontine angle tumours) it may entirely replace other tests (eg myelography, air contrast, CT) which are substantially less accurate and/or more invasive. In other situations (eg hemispheric brain tumours, lumbar disc protrusions) when other tests, such as CT, can be as accurate, MRI is not usually or initially indicated because it is currently more expensive and of limited availability. However, balanced against this is the fact that it does not expose the patient to potentially harmful ionising radiation. It is also stressed that MRI images depend on complex, widely variable and, as yet, incompletely understood parameters. There is concern that this may result in false positive diagnoses, especially where MRI is used alone as a screening test, or used as the initial test. For several reasons (availability, cost, medical and diagnostic efficacy), the specific comments on indications for MRI presented are based upon the assumption that MRI is a tertiary and complementary imaging examination

  4. MRI of the fetal abdomen

    International Nuclear Information System (INIS)

    Hoermann, M.; Brugger, P.C.; Witzani, L.; Prayer, D.

    2006-01-01

    Magnetic resonance imaging (MRI) is an important diagnostic component for central nervous system and thoracic diseases during fetal development. Although ultrasound remains the method of choice for observing the fetus during pregnancy, fetal MRI is being increasingly used as an additional technique for the accurate diagnosis of abdominal diseases. Recent publications confirm the value of MRI in the diagnosis of fetal gastrointestinal tract and urogenital system diseases. The following report provides an overview of MRI-examination techniques for the most frequent diseases of the abdomen. (orig.) [de

  5. MRI finding of hemangioblastomas

    International Nuclear Information System (INIS)

    Park, Seung Cheol; Oh, Min Cheol; Chung, Hwan Hoon; Seol, Hye Young; Lee, Nam Joon; Kim, Jung Hyuk

    1994-01-01

    The purpose of this study is to evaluate the findings of magnetic resonance imaging (MRI) of posterior fossa hemanangioblastoma and usefulness of contrast enhancement with Gd-DTPA. Seven patients with posterior fossa hemangioblastoma were studied with both pre- and post-enhanced MRI. The MR images were reviewed regarding the location, size, signal intensities of cysts and mural nodules, and their contrast enhancement pattern. Five tumors were located in cerebellar hemisphere, one in vermis, and one in posterior part of medulla. One patient with von Hippel-Lindau disease had a medullary hemangioblastoma with multiple pancreatic cysts. In 6 cases, the major portion of the tumor was cysts and had small mulkal nodules. The solid portion was relatively lange in one cases, cemprising half of the tumor cysts were oval shaped and their sized were 3-6.7 cm in diameter. In five cases(71%), septations were noted within the cysts. Cysts were isointense or slightly hyperintense on T1-weighted image and hyperintense on T2- weighted image compared with cerebrospinal fluid. Mural nodules were oval or rounded radiotherapy had better prognosis than those treated with radiotherapy alwas 0.5-2.5 cm in diameter. Mural nodules were isointense to gray matter. They were detected in five cases on T1-weighted images and one case on T2-weighted images. In two cases, vascular signal void area was noted in mural nodules. On contrast-enhanced T1-weighted images, all mural nodules were intensely enhanced. MRI provide to be a good diagnostic method to detect and characterize posterior fossa hemangioblastoma. The most common finding is Cystic posterior fossa lesion with enhancing mural nodule. Contrast enhancement is essential for specific diagnosis

  6. MRI case studies

    International Nuclear Information System (INIS)

    Huggett, S.; Barber, J.

    1989-01-01

    Three case studies are presented to show the value of magnetic resonance imaging used in conjunction with other imaging techniques. In each case MRI proved a vital diagnostic tool and superior to CT in showing firstly the haematoma in a patient with aphasia and right-sided weakness, secondly the size of the disc herniation in a patient with severe leg and ankle pains and thirdly the existence of a metastatic lesion in a patient with a previous history of breast cancer. 11 figs

  7. Tarsaltunnel syndrome - MRI diagnosis

    International Nuclear Information System (INIS)

    Trattnig, S.; Helbich, T.; Imhof, H.

    1995-01-01

    Clinical findings and symptoms of tarsal tunnel are commonly vague and diffuse and electrodiagnostic studies do not provide definitive diagnosis. MR imaging with its excellent soft tissue contrast can demonstrate clearly the anatomy of the tarsal tunnel and its contents. MRI is able to demonstrate a space-occypyinglesion and its relationship to the posterior tibial nerve and its branches. This information aids in surgical planning by determining the extent of the decompression required. MR imaging may also be used to follow up non-surgical causes of tarsal tunnel syndrome such as tenosynovitis. (orig.) [de

  8. Rabies, encephalomyelitis: MRI findings

    International Nuclear Information System (INIS)

    Peloso, Raul; Gonzalez, Roberto

    2002-01-01

    The authors present a 14 year old patient who started with walking and swallowing difficulty; followed by fever, abdominal and lower back pain. Mechanical breathing difficulties required a respiratory mechanic assistance. The diagnosis of Guillain-Barre syndrome was thought at first. Since the patient have had previous contact with a bat two months before the symptoms began, this suggested rabies as the main diagnosis, which was later confirmed by hair-bulb, cornea, oral mucosa and salival immunofluorescence. The brain and spinal cord MRI showed focal lesions in T2 and FLAIR sequences, compatible with encephalomyelitis. (author)

  9. Magnetic rubber inspection (MRI)

    International Nuclear Information System (INIS)

    Carro, L.

    1997-01-01

    Magnetic Rubber Inspection (MRI) was developed to inspect for small cracks and flaws encountered in high performance aircraft. A formula of very fine magnetic particles immersed in a room temperature curing rubber is catalysed and poured into dams (retainers) on the surface of the part to be inspected. Inducing a magnetic field then causes the particles to be drawn to discontinuities in the component under test. These indicating particles are held to the discontinuity by magnetic attraction, as the rubber cures. The solid rubber cast (Replica) is then removed and examined under a microscope for indicating lines of particle concentrations. 3 refs., 6 figs

  10. Ovarian cysts on prenatal MRI

    International Nuclear Information System (INIS)

    Nemec, Ursula; Nemec, Stefan F.; Bettelheim, Dieter; Brugger, Peter C.; Horcher, Ernst; Schöpf, Veronika; Graham, John M.; Rimoin, David L.; Weber, Michael; Prayer, Daniela

    2012-01-01

    Objective: Ovarian cysts are the most frequently encountered intra-abdominal masses in females in utero. They may, at times, require perinatal intervention. Using magnetic resonance imaging (MRI) as an adjunct to ultrasonography (US) in prenatal diagnosis, we sought to demonstrate the ability to visualize ovarian cysts on prenatal MRI. Materials and methods: This retrospective study included 17 fetal MRI scans from 16 female fetuses (23–37 gestational weeks) with an MRI diagnosis of ovarian cysts after suspicious US findings. A multiplanar MRI protocol was applied to image and to characterize the cysts. The US and MRI findings were compared, and the prenatal findings were compared with postnatal imaging findings or histopathology. Results: Simple ovarian cysts were found in 10/16 cases and complex cysts in 7/16 cases, including one case with both. In 11/16 (69%) cases, US and MRI diagnoses were in agreement, and, in 5/16 (31%) cases, MRI specified or expanded the US diagnosis. In 6/16 cases, postnatal US showed that the cysts spontaneously resolved or decreased in size, and in 1/16 cases, postnatal imaging confirmed a hemorrhagic cyst. In 4/16 cases, the prenatal diagnoses were confirmed by surgery/histopathology, and for the rest, postnatal correlation was not available. Conclusion: Our results illustrate the MRI visualization of ovarian cysts in utero. In most cases, MRI will confirm the US diagnosis. In certain cases, MRI may provide further diagnostic information, additional to US, which is the standard technique for diagnosis, monitoring, and treatment planning.

  11. Ovarian cysts on prenatal MRI

    Energy Technology Data Exchange (ETDEWEB)

    Nemec, Ursula [Department of Radiology, Division of Neuroradiology and Musculoskeletal Radiology, Medical University Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Nemec, Stefan F., E-mail: stefan.nemec@meduniwien.ac.at [Department of Radiology, Division of Neuroradiology and Musculoskeletal Radiology, Medical University Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Medical Genetics Institute, Cedars Sinai Medical Center, 8700 Beverly Boulevard, PACT Suite 400, Los Angeles, CA 90048 (United States); Bettelheim, Dieter [Department of Obstetrics and Gynaecology, Division of Prenatal Diagnosis and Therapy, Medical University Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Brugger, Peter C. [Center of Anatomy and Cell Biology, Integrative Morphology Group, Medical University Vienna, Waehringerstrasse 13, A-1090 Vienna (Austria); Horcher, Ernst [Department of Pediatric Surgery, Medical University Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Schoepf, Veronika [Department of Radiology, Division of Neuroradiology and Musculoskeletal Radiology, Medical University Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Graham, John M.; Rimoin, David L. [Medical Genetics Institute, Cedars Sinai Medical Center, 8700 Beverly Boulevard, PACT Suite 400, Los Angeles, CA 90048 (United States); Weber, Michael; Prayer, Daniela [Department of Radiology, Division of Neuroradiology and Musculoskeletal Radiology, Medical University Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria)

    2012-08-15

    Objective: Ovarian cysts are the most frequently encountered intra-abdominal masses in females in utero. They may, at times, require perinatal intervention. Using magnetic resonance imaging (MRI) as an adjunct to ultrasonography (US) in prenatal diagnosis, we sought to demonstrate the ability to visualize ovarian cysts on prenatal MRI. Materials and methods: This retrospective study included 17 fetal MRI scans from 16 female fetuses (23-37 gestational weeks) with an MRI diagnosis of ovarian cysts after suspicious US findings. A multiplanar MRI protocol was applied to image and to characterize the cysts. The US and MRI findings were compared, and the prenatal findings were compared with postnatal imaging findings or histopathology. Results: Simple ovarian cysts were found in 10/16 cases and complex cysts in 7/16 cases, including one case with both. In 11/16 (69%) cases, US and MRI diagnoses were in agreement, and, in 5/16 (31%) cases, MRI specified or expanded the US diagnosis. In 6/16 cases, postnatal US showed that the cysts spontaneously resolved or decreased in size, and in 1/16 cases, postnatal imaging confirmed a hemorrhagic cyst. In 4/16 cases, the prenatal diagnoses were confirmed by surgery/histopathology, and for the rest, postnatal correlation was not available. Conclusion: Our results illustrate the MRI visualization of ovarian cysts in utero. In most cases, MRI will confirm the US diagnosis. In certain cases, MRI may provide further diagnostic information, additional to US, which is the standard technique for diagnosis, monitoring, and treatment planning.

  12. MRI in intraspinal tuberculosis

    International Nuclear Information System (INIS)

    Gupta, R.K.; Gupta, S.; Kumar, S.; Kohli, A.; Misra, U.K.; Gujral, R.B.

    1994-01-01

    We studied 20 patients with intraspinal tuberculosis (TB), to characterise the MRI features of tuberculous meningitis and myelitis. MRI leptomeningitis and intramedullary involvement in 11 patients, intramedullary lesions alone in 5, leptomeningitis alone in 2, and isolated extradural disease in 2. TB leptomeningitis was characterised by loculation of the cerebrospinal fluid (CSF), nerve root thickening and clumping (seen only in the lumbar region) or complete obliteration of the subarachnoid space on unenhanced images. Gd-DTPA-enhanced images proved useful in 6 cases, revealing linear enhancement of the surface of the spinal cord and nerve roots or plaque-like enhancement of the dura-arachnoid mater complex. Intramedullary lesions included tuberculomas (8), cord oedema (5) and cavitation (3). In seven cases of intramedullary tuberculoma multiple lesions with skip areas were seen, without significant cord swelling. One patient had an isolated lesion in the conus medullaris. The lesions were iso- or hypointense on T1-weighted images, iso-, hypo- or hyperintense on T2-weighted images and showed rim or nodular enhancement with contrast medium. (orig.)

  13. Musculoskeletal MRI: dedicated systems

    International Nuclear Information System (INIS)

    Masciocchi, C.; Barile, A.; Satragno, L.

    2000-01-01

    The ''dedicated'' MRI units have characteristics of high diagnostic accuracy and lower installation and management costs as compared with whole-body systems. The dedicated MRI units are easy to install. The low weight allows their installation also under unfavorable circumstances. In a dedicated system cost-effectiveness and ease of installation must be accompanied by the capability of providing high-quality images. In our experience, the high number of examinations performed, the most part of which provided with the surgical controls, allowed an accurate evaluation of the diagnostic potentialities of the dedicated magnet. We were not able to perform the examinations in only 3 % of cases due to the physical shape of the patient and the clinical condition of the patient which may hinder the correct positioning of the limb. The overlapping of the diagnostic accuracy of the E-scan and Artoscan units in the study of the lower limbs, compared with whole-body units and surgery, prompted us to exploit the potentialities of the E-Scan in the study of the shoulder. We had a good correlation between E-Scan, whole-body units, and surgical findings, which confirmed the high diagnostic accuracy of the dedicated system. In conclusion, in our experience carried out in the musculoskeletal system, the dedicated magnets showed promising results. Their diagnostic reliability and utility was comparable to that obtained from conventional units operating at higher magnetic fields. (orig.)

  14. Cardiovascular MRI with ferumoxytol

    International Nuclear Information System (INIS)

    Finn, J.P.; Nguyen, K.-L.; Han, F.; Zhou, Z.; Salusky, I.; Ayad, I.; Hu, P.

    2016-01-01

    The practice of contrast-enhanced magnetic resonance angiography (CEMRA) has changed significantly in the span of a decade. Concerns regarding gadolinium (Gd)-associated nephrogenic systemic fibrosis in those with severely impaired renal function spurred developments in low-dose CEMRA and non-contrast MRA as well as efforts to seek alternative MR contrast agents. Originally developed for MR imaging use, ferumoxytol (an ultra-small superparamagnetic iron oxide nanoparticle), is currently approved by the US Food and Drug Administration for the treatment of iron deficiency anaemia in adults with renal disease. Since its clinical availability in 2009, there has been rising interest in the scientific and clinical use of ferumoxytol as an MR contrast agent. The unique physicochemical and pharmacokinetic properties of ferumoxytol, including its long intravascular half-life and high r 1 relaxivity, support a spectrum of MRI applications beyond the scope of Gd-based contrast agents. Moreover, whereas Gd is not found in biological systems, iron is essential for normal metabolism, and nutritional iron deficiency poses major public health challenges worldwide. Once the carbohydrate shell of ferumoxytol is degraded, the elemental iron at its core is incorporated into the reticuloendothelial system. These considerations position ferumoxytol as a potential game changer in the field of CEMRA and MRI. In this paper, we aim to summarise our experience with the cardiovascular applications of ferumoxytol and provide a brief synopsis of ongoing investigations on ferumoxytol-enhanced MR applications.

  15. MRI of the cartilage

    Energy Technology Data Exchange (ETDEWEB)

    Imhof, H.; Noebauer-Huhmann, I.-M.; Krestan, C.; Gahleitner, A.; Marlovits, S.; Trattnig, S. [Department of Osteology, Universitaetklinik fuer Radiodiagnostik, AKH-Vienna, Waehringer Guertel 18-20, 1090 Vienna (Austria); Sulzbacher, I. [Universitaetsklinik fuer Pathologie Vienna, Waehringer Guertel 18-20, 1090 Vienna (Austria)

    2002-11-01

    With the introduction of fat-suppressed gradient-echo and fast spin-echo (FSE) sequences in clinical routine MR visualization of the hyaline articular cartilage is routinely possible in the larger joints. While 3D gradient-echo with fat suppression allows exact depiction of the thickness and surface of cartilage, FSE outlines the normal and abnormal internal structures of the hyaline cartilage; therefore, both sequences seem to be necessary in a standard MRI protocol for cartilage visualization. In diagnostically ambiguous cases, in which important therapeutic decisions are required, direct MR arthrography is the established imaging standard as an add-on procedure. Despite the social impact and prevalence, until recent years there was a paucity of knowledge about the pathogenesis of cartilage damage. With the introduction of high-resolution MRI with powerful surface coils and fat-suppression techniques, visualization of the articular cartilage is now routinely possible in many joints. After a short summary of the anatomy and physiology of the hyaline cartilage, the different MR imaging methods are discussed and recommended standards are suggested. (orig.)

  16. Getting an MRI (For Kids)

    Medline Plus

    Full Text Available ... A) Staying Safe Videos for Educators Search English Español Getting an MRI (Video) KidsHealth / For Kids / Getting an MRI (Video) Print en español Obtención de una resonancia magnética, RM (video) An ...

  17. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info About Us News Physician ... absolutely necessary for medical treatment. See the MRI Safety page for more information about pregnancy and MRI. ...

  18. Postmortem MRI of bladder agenesis

    Energy Technology Data Exchange (ETDEWEB)

    Barber, Brendan R. [St George' s Hospital, Radiology Department, London (United Kingdom); Weber, Martin A. [Great Ormond Street Hospital for Children, Department of Histopathology, London (United Kingdom); Bockenhauer, Detlef [Great Ormond Street Hospital for Children, Department of Nephrology, London (United Kingdom); Hiorns, Melanie P.; McHugh, Kieran [Great Ormond Street Hospital for Children, Radiology Department, London (United Kingdom)

    2011-01-15

    We report a 35-week preterm neonate with bladder agenesis and bilateral dysplastic kidneys. A suprapubic catheter was inadvertently inserted into one of the larger inferior cysts of the left dysplastic kidney. A postmortem MRI scan was performed with the findings being confirmed on autopsy. We are unaware of another postmortem MRI study demonstrating bladder agenesis. (orig.)

  19. Postmortem MRI of bladder agenesis

    International Nuclear Information System (INIS)

    Barber, Brendan R.; Weber, Martin A.; Bockenhauer, Detlef; Hiorns, Melanie P.; McHugh, Kieran

    2011-01-01

    We report a 35-week preterm neonate with bladder agenesis and bilateral dysplastic kidneys. A suprapubic catheter was inadvertently inserted into one of the larger inferior cysts of the left dysplastic kidney. A postmortem MRI scan was performed with the findings being confirmed on autopsy. We are unaware of another postmortem MRI study demonstrating bladder agenesis. (orig.)

  20. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician ... Magnetic resonance imaging (MRI) is a noninvasive medical test that physicians use to diagnose medical conditions. MRI ...

  1. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... structures of the brain and can also provide functional information (fMRI) in selected cases. MR images of ... Articles and Media MR Angiography (MRA) Magnetic Resonance, Functional (fMRI) - Brain Head and Neck Cancer Treatment Brain ...

  2. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... fitting and has no metal fasteners. Guidelines about eating and drinking before an MRI exam vary with the specific exam and with the imaging facility. Unless you are told otherwise, you may follow your regular daily routine and take food and medications as usual. Some MRI examinations may ...

  3. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... metallic items, which can distort MRI images removable dental work pens, pocket knives and eyeglasses body piercings In most cases, an MRI exam is safe for patients with metal implants, except for a few types. People with the ...

  4. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us ... absolutely necessary for medical treatment. See the MRI Safety page for more information about pregnancy and MRI. ...

  5. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... can also provide functional information (fMRI) in selected cases. MR images of the brain and other cranial structures are clearer and more detailed than with other imaging methods. This detail makes MRI an invaluable tool in early diagnosis and evaluation of many conditions, ...

  6. Getting an MRI (For Kids)

    Medline Plus

    Full Text Available ... First Aid & Safety Doctors & Hospitals Videos Recipes for Kids Kids site Sitio para niños How the Body Works ... English Español Getting an MRI (Video) KidsHealth / For Kids / Getting an MRI (Video) Print en español Obtención ...

  7. A Technique for Generating Volumetric Cine MRI (VC-MRI)

    Science.gov (United States)

    Harris, Wendy; Ren, Lei; Cai, Jing; Zhang, You; Chang, Zheng; Yin, Fang-Fang

    2016-01-01

    Purpose To develop a technique to generate on-board volumetric-cine MRI (VC-MRI) using patient prior images, motion modeling and on-board 2D-cine MRI. Methods One phase of a 4D-MRI acquired during patient simulation is used as patient prior images. 3 major respiratory deformation patterns of the patient are extracted from 4D-MRI based on principal-component-analysis. The on-board VC-MRI at any instant is considered as a deformation of the prior MRI. The deformation field is represented as a linear combination of the 3 major deformation patterns. The coefficients of the deformation patterns are solved by the data fidelity constraint using the acquired on-board single 2D-cine MRI. The method was evaluated using both XCAT simulation of lung cancer patients and MRI data from four real liver cancer patients. The accuracy of the estimated VC-MRI was quantitatively evaluated using Volume-Percent-Difference(VPD), Center-of-Mass-Shift(COMS), and target tracking errors. Effects of acquisition orientation, region-of-interest(ROI) selection, patient breathing pattern change and noise on the estimation accuracy were also evaluated. Results Image subtraction of ground-truth with estimated on-board VC-MRI shows fewer differences than image subtraction of ground-truth with prior image. Agreement between profiles in the estimated and ground-truth VC-MRI was achieved with less than 6% error for both XCAT and patient data. Among all XCAT scenarios, the VPD between ground-truth and estimated lesion volumes was on average 8.43±1.52% and the COMS was on average 0.93±0.58mm across all time-steps for estimation based on the ROI region in the sagittal cine images. Matching to ROI in the sagittal view achieved better accuracy when there was substantial breathing pattern change. The technique was robust against noise levels up to SNR=20. For patient data, average tracking errors were less than 2 mm in all directions for all patients. Conclusions Preliminary studies demonstrated the

  8. MRI in ischemic heart disease

    International Nuclear Information System (INIS)

    Hazirolan, T.

    2012-01-01

    Full text: The role of magnetic resonance imaging in the evaluation of ischemic heart disease has increased over the last years. Cardiac MRI is the only imaging modality that provides 'one stop shop' assessment. Information about ventricular function, myocardial ischemia and myocardial viability can be obtained in a single cardiac MRI session. Additionally, Cardiac MRI has become a gold standard method in evaluation of myocardial viability and in assessment of ventricular mass and function. As a result, cardiac MRI enable radiologist to comprehensively assess ischemic heart disease. The aim of this presentation is to provide the reader a state-of-the art on how the newest cardiac MRI techniques can be used to study ischemic heart disease patients.

  9. MRI diagnosis for prostate cancer

    Energy Technology Data Exchange (ETDEWEB)

    Tamada, Tsutomu; Nagai, Kiyohisa; Imai, Shigeki; Kajihara, Yasumasa; Jo, Yoshimasa; Tanaka, Hiroyoshi; Fukunaga, Masao (Kawasaki Medical School, Kurashiki, Okayama (Japan)); Matsuki, Takakazu

    1998-01-01

    Recently, in Japan, both the Westernization of life styles and the advent of an aged-society have led to an increase in the incidence of prostate cancer. In making a localizing diagnosis of prostate cancer, magnetic resonance imaging (MRI), which has excellent contrast resolution, and transrectal ultrasonography, are used clinically, and their usefulness is being established. MRI is employed in the diagnosis of prostate cancer to detect tumors, and to determine the stage of such tumors. For the visualization of prostate cancer by MRI, T2-weighted axial images are used exclusively. After becoming familiar with normal prostate images, it is important to evaluate the localization of a tumor, and the invasion of the capsule and seminal vesicles. Future applications of new techniques for MRI will undoubtedly be found. In this paper, the present state of MRI diagnosis of prostate cancer at Kawasaki Medical School Hospital will be reviewed. (author)

  10. MRI diagnosis for prostate cancer

    Energy Technology Data Exchange (ETDEWEB)

    Tamada, Tsutomu; Nagai, Kiyohisa; Imai, Shigeki; Kajihara, Yasumasa; Jo, Yoshimasa; Tanaka, Hiroyoshi; Fukunaga, Masao [Kawasaki Medical School, Kurashiki, Okayama (Japan); Matsuki, Takakazu

    1998-12-31

    Recently, in Japan, both the Westernization of life styles and the advent of an aged-society have led to an increase in the incidence of prostate cancer. In making a localizing diagnosis of prostate cancer, magnetic resonance imaging (MRI), which has excellent contrast resolution, and transrectal ultrasonography, are used clinically, and their usefulness is being established. MRI is employed in the diagnosis of prostate cancer to detect tumors, and to determine the stage of such tumors. For the visualization of prostate cancer by MRI, T2-weighted axial images are used exclusively. After becoming familiar with normal prostate images, it is important to evaluate the localization of a tumor, and the invasion of the capsule and seminal vesicles. Future applications of new techniques for MRI will undoubtedly be found. In this paper, the present state of MRI diagnosis of prostate cancer at Kawasaki Medical School Hospital will be reviewed. (author)

  11. MRI-powered biomedical devices.

    Science.gov (United States)

    Hovet, Sierra; Ren, Hongliang; Xu, Sheng; Wood, Bradford; Tokuda, Junichi; Tse, Zion Tsz Ho

    2017-11-16

    Magnetic resonance imaging (MRI) is beneficial for imaging-guided procedures because it provides higher resolution images and better soft tissue contrast than computed tomography (CT), ultrasound, and X-ray. MRI can be used to streamline diagnostics and treatment because it does not require patients to be repositioned between scans of different areas of the body. It is even possible to use MRI to visualize, power, and control medical devices inside the human body to access remote locations and perform minimally invasive procedures. Therefore, MR conditional medical devices have the potential to improve a wide variety of medical procedures; this potential is explored in terms of practical considerations pertaining to clinical applications and the MRI environment. Recent advancements in this field are introduced with a review of clinically relevant research in the areas of interventional tools, endovascular microbots, and closed-loop controlled MRI robots. Challenges related to technology and clinical feasibility are discussed, including MRI based propulsion and control, navigation of medical devices through the human body, clinical adoptability, and regulatory issues. The development of MRI-powered medical devices is an emerging field, but the potential clinical impact of these devices is promising.

  12. MRI of plants and foods

    Science.gov (United States)

    Van As, Henk; van Duynhoven, John

    2013-04-01

    The importance and prospects for MRI as applied to intact plants and to foods are presented in view of one of humanity's most pressing concerns, the sustainable and healthy feeding of a worldwide increasing population. Intact plants and foods have in common that their functionality is determined by complex multiple length scale architectures. Intact plants have an additional level of complexity since they are living systems which critically depend on transport and signalling processes between and within tissues and organs. The combination of recent cutting-edge technical advances and integration of MRI accessible parameters has the perspective to contribute to breakthroughs in understanding complex regulatory plant performance mechanisms. In food science and technology MRI allows for quantitative multi-length scale structural assessment of food systems, non-invasive monitoring of heat and mass transport during shelf-life and processing, and for a unique view on food properties under shear. These MRI applications are powerful enablers of rationally (re)designed food formulations and processes. Limitations and bottlenecks of the present plant and food MRI methods are mainly related to short T2 values and susceptibility artefacts originating from small air spaces in tissues/materials. We envisage cross-fertilisation of solutions to overcome these hurdles in MRI applications in plants and foods. For both application areas we witness a development where MRI is moving from highly specialised equipment to mobile and downscaled versions to be used by a broad user base in the field, greenhouse, food laboratory or factory.

  13. MRI findings in bipartite patella

    International Nuclear Information System (INIS)

    Kavanagh, Eoin C.; Zoga, Adam; Omar, Imran; Ford, Stephanie; Eustace, Stephen; Schweitzer, Mark

    2007-01-01

    Bipartite patella is a known cause of anterior knee pain. Our purpose was to detail the magnetic resonance imaging (MRI) features of bipartite patella in a retrospective cohort of patients imaged at our institution. MRI exams from 53 patients with findings of bipartite patella were evaluated to assess for the presence of bone marrow edema within the bipartite fragment and for the presence of abnormal signal across the synchondrosis or pseudarthrosis. Any other significant knee pathology seen at MRI was also recorded. We also reviewed 400 consecutive knee MRI studies to determine the MRI prevalence of bipartite patella. Of the 53 patients with bipartite patella 40 (75%) were male; 35 (66%) had edema within the bipartite fragment. Of the 18 with no edema an alternative explanation for knee pain was found in 13 (72%). Edema within the bipartite fragment was the sole finding in 26 of 53 (49%) patients. Bipartite patella was seen in 3 (0.7%) of 400 patients. In patients with bipartite patella at knee MRI, bone marrow edema within the bipartite fragment was the sole finding on knee MRI in almost half of the patients in our series. (orig.)

  14. Situs anomalies on prenatal MRI

    International Nuclear Information System (INIS)

    Nemec, Stefan F.; Brugger, Peter C.; Nemec, Ursula; Bettelheim, Dieter; Kasprian, Gregor; Amann, Gabriele; Rimoin, David L.; Graham, John M.; Prayer, Daniela

    2012-01-01

    Objective: Situs anomalies refer to an abnormal organ arrangement, which may be associated with severe errors of development. Due regard being given to prenatal magnetic resonance imaging (MRI) as an adjunct to ultrasonography (US), this study sought to demonstrate the in utero visualization of situs anomalies on MRI, compared to US. Materials and methods: This retrospective study included 12 fetuses with situs anomalies depicted on fetal MRI using prenatal US as a comparison modality. With an MRI standard protocol, the whole fetus was assessed for anomalies, with regard to the position and morphology of the following structures: heart; venous drainage and aorta; stomach and intestines; liver and gallbladder; and the presence and number of spleens. Results: Situs inversus totalis was found in 3/12 fetuses; situs inversus with levocardia in 1/12 fetuses; situs inversus abdominis in 2/12 fetuses; situs ambiguous with polysplenia in 3/12 fetuses, and with asplenia in 2/12 fetuses; and isolated dextrocardia in 1/12 fetuses. Congenital heart defects (CHDs), vascular anomalies, and intestinal malrotations were the most frequent associated malformations. In 5/12 cases, the US and MRI diagnoses were concordant. Compared to US, in 7/12 cases, additional MRI findings specified the situs anomaly, but CHDs were only partially visualized in six cases. Conclusions: Our initial MRI results demonstrate the visualization of situs anomalies and associated malformations in utero, which may provide important information for perinatal management. Using a standard protocol, MRI may identify additional findings, compared to US, which confirm and specify the situs anomaly, but, with limited MRI visualization of fetal CHDs.

  15. MRI of cystic pituitary tumors

    Energy Technology Data Exchange (ETDEWEB)

    Tokunaga, Hitoshi; Hoshi, Seiichiro; Sunada, Souichi; Sunami, Kenro [Kawatetsu Chiba Hospital (Japan); Saeki, Naokatsu; Yamaura, Akira

    1998-11-01

    We retrospectively reviewed MRI findings of 17 patients with 3 histologically proven cystic pituitary tumors. They consisted of 10 cystic pituitary adenomas, 4 craniopharyngiomas and 3 Rathke`s cleft cysts. We analyzed the following MRI parameters such as cyst wall appearance, enhancement pattern of cyst wall, location of residual pituitary gland and location of tumor. They were clinically significant parameters for histological differentiation. Even though combinations of such MRI parameters helped for more accurate preoperative diagnosis, the differentiation between craniopharyngioma and Rathke`s cleft cyst was difficult in some cases. (author)

  16. Cerebral malaria: susceptibility weighted MRI

    Directory of Open Access Journals (Sweden)

    Vinit Baliyan

    2015-03-01

    Full Text Available Cerebral malaria is one of the fatal complications of Plasmodium falciparum infection. Pathogenesis involves cerebral microangiopathy related to microvascular plugging by infected red blood cells. Conventional imaging with MRI and CT do not reveal anything specific in case of cerebral malaria. Susceptibility weighted imaging, a recent advance in the MRI, is very sensitive to microbleeds related to microangiopathy. Histopathological studies in cerebral malaria have revealed microbleeds in brain parenchyma secondary to microangiopathy. Susceptibility weighted imaging, being exquisitely sensitive to microbleeds may provide additional information and improve the diagnostic accuracy of MRI in cerebral malaria.

  17. MRI of cystic pituitary tumors

    International Nuclear Information System (INIS)

    Tokunaga, Hitoshi; Hoshi, Seiichiro; Sunada, Souichi; Sunami, Kenro; Saeki, Naokatsu; Yamaura, Akira

    1998-01-01

    We retrospectively reviewed MRI findings of 17 patients with 3 histologically proven cystic pituitary tumors. They consisted of 10 cystic pituitary adenomas, 4 craniopharyngiomas and 3 Rathke's cleft cysts. We analyzed the following MRI parameters such as cyst wall appearance, enhancement pattern of cyst wall, location of residual pituitary gland and location of tumor. They were clinically significant parameters for histological differentiation. Even though combinations of such MRI parameters helped for more accurate preoperative diagnosis, the differentiation between craniopharyngioma and Rathke's cleft cyst was difficult in some cases. (author)

  18. MRI of the postoperative shoulder

    International Nuclear Information System (INIS)

    Zlatkin, Michael B.

    2002-01-01

    Performing and interpreting MRI of the shoulder in patients after surgery is a difficult task. The normal anatomic features are distorted by the surgical alterations as well as the artifacts that result from metal and other materials used in the surgical procedures. This article reviews the common surgical procedures undertaken in patients with rotator cuff disease and shoulder instability, and how they affect the appearance of the relevant anatomic structures on MRI examination. It also reviews the more common causes for residual and recurrent abnormalities seen in such patients and how MRI can be used to diagnose such lesions, thus aiding the orthopedic surgeon in treating these difficult clinical problems. (orig.)

  19. MRI of congenital urethroperineal fistula

    Energy Technology Data Exchange (ETDEWEB)

    Ghadimi-Mahani, Maryam; Dillman, Jonathan R.; Pai, Deepa; DiPietro, Michael [C. S. Mott Children' s Hospital, Department of Radiology, Section of Pediatric Radiology, University of Michigan Health System, Ann Arbor, MI (United States); Park, John [C. S. Mott Children' s Hospital, Department of Pediatric Urology, University of Michigan Health System, Ann Arbor, MI (United States)

    2010-12-15

    We present the MRI features of a congenital urethroperineal fistula diagnosed in a 12-year-old boy being evaluated after a single urinary tract infection. This diagnosis was initially suggested by voiding cystourethrogram and confirmed by MRI. Imaging revealed an abnormal fluid-filled tract arising from the posterior urethra and tracking to the perineal skin surface that increased in size during micturition. Surgical resection and histopathological evaluation of the abnormal tract confirmed the diagnosis of congenital urethroperineal fistula. MRI played important roles in confirming the diagnosis and assisting surgical planning. (orig.)

  20. MRI of congenital urethroperineal fistula

    International Nuclear Information System (INIS)

    Ghadimi-Mahani, Maryam; Dillman, Jonathan R.; Pai, Deepa; DiPietro, Michael; Park, John

    2010-01-01

    We present the MRI features of a congenital urethroperineal fistula diagnosed in a 12-year-old boy being evaluated after a single urinary tract infection. This diagnosis was initially suggested by voiding cystourethrogram and confirmed by MRI. Imaging revealed an abnormal fluid-filled tract arising from the posterior urethra and tracking to the perineal skin surface that increased in size during micturition. Surgical resection and histopathological evaluation of the abnormal tract confirmed the diagnosis of congenital urethroperineal fistula. MRI played important roles in confirming the diagnosis and assisting surgical planning. (orig.)

  1. Brain venous pathologies: MRI findings

    International Nuclear Information System (INIS)

    Salvatico, Rosana; Gonzalez, Alejandro; Yanez, Paulina; Romero, Carlos; Trejo, Mariano; Lambre, Hector

    2006-01-01

    Purpose: To describe MRI findings of the different brain venous pathologies. Material and Methods: Between January 2002 and March 2004, 18 patients were studied 10 males and 8 females between 6 and 63 years old; with different brain venous pathologies. In all cases brain MRI were performed including morphological sequences with and without gadolinium injection and angiographic venous sequences. Results: 10 venous occlusions were found, 6 venous angiomas, and 2 presented varices secondary to arteriovenous dural fistula. Conclusion: Brain venous pathologies can appear in many different clinical contexts, with different prognosis and treatment. In all the cases brain MRI was the best imaging study to disclose typical morphologic abnormalities. (author) [es

  2. Anaesthesia for MRI: ….child's play?

    African Journals Online (AJOL)

    Adele

    radiology as well as in the operating room. MRI offers superior soft-tissue contrast and can create images through any body plane. The success of an MRI ... MRI then became a practical real- ity with the ... Magnetic field strengths in MRI systems range from 0. 15-3. 0 tesla. ... Time varied magnetic field interference. Magnetic ...

  3. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... MRI can detect stroke at a very early stage by mapping the motion of water molecules in ... is because traction devices and many types of life support equipment may distort the MR images and ...

  4. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... told otherwise, take your regular medications as usual. Leave jewelry at home and wear loose, comfortable clothing. ... contrast material except when absolutely necessary for medical treatment. See the MRI Safety page for more information ...

  5. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... images removable dental work pens, pocket knives and eyeglasses body piercings In most cases, an MRI exam ... and treatments have special pediatric considerations. The teddy bear denotes child-specific content. Related Articles and Media ...

  6. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... any recent surgeries. Some conditions, such as severe kidney disease, may prevent you from being given gadolinium contrast ... an MRI. If you have a history of kidney disease or liver transplant, it will be necessary to ...

  7. MRI appearance of muscle denervation

    Energy Technology Data Exchange (ETDEWEB)

    Kamath, S. [University Hospital of Wales, Department of Radiology, Cardiff (United Kingdom); Venkatanarasimha, N.; Walsh, M.A.; Hughes, P.M. [Derriford Hospital, Department of Radiology, Plymouth (United Kingdom)

    2008-05-15

    Muscle denervation results from a variety of causes including trauma, neoplasia, neuropathies, infections, autoimmune processes and vasculitis. Traditionally, the diagnosis of muscle denervation was based on clinical examination and electromyography. Magnetic resonance imaging (MRI) offers a distinct advantage over electromyography, not only in diagnosing muscle denervation, but also in determining its aetiology. MRI demonstrates characteristic signal intensity patterns depending on the stage of muscle denervation. The acute and subacutely denervated muscle shows a high signal intensity pattern on fluid sensitive sequences and normal signal intensity on T1-weighted MRI images. In chronic denervation, muscle atrophy and fatty infiltration demonstrate high signal changes on T1-weighted sequences in association with volume loss. The purpose of this review is to summarise the MRI appearance of denervated muscle, with special emphasis on the signal intensity patterns in acute and subacute muscle denervation. (orig.)

  8. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... the exam. MRI scanners are air-conditioned and well-lit. Music may be played through the headphones ... full size with caption Pediatric Content Some imaging tests and treatments have special pediatric considerations. The teddy ...

  9. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... metallic items, which can distort MRI images removable dental work pens, pocket knives and eyeglasses body piercings ... and send a signed report to your primary care or referring physician, who will share the results ...

  10. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... a risk, depending on their nature and the strength of the MRI magnet. Many implanted devices will ... full size with caption Pediatric Content Some imaging tests and treatments have special pediatric considerations. The teddy ...

  11. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... scans, MRI does not utilize ionizing radiation. Instead, radiofrequency pulses re-align hydrogen atoms that naturally exist ... thumping sounds when the coils that generate the radiofrequency pulses are activated. Some centers provide earplugs, while ...

  12. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... tissue from which they come. The MR scanner captures this energy and creates a picture of the ... imaging based on the electrical activity of the heart, such as electrocardiography (EKG). MRI generally is not ...

  13. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... tumors stroke infections developmental anomalies hydrocephalus — dilatation of fluid spaces within the brain (ventricles) causes of epilepsy ( ... may not always distinguish between cancer tissue and fluid, known as edema . MRI typically costs more and ...

  14. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... Imaging (MRI) procedure View full size with caption Pediatric Content Some imaging tests and treatments have special pediatric considerations. The teddy bear denotes child-specific content. ...

  15. Thermal injuries associated with MRI

    International Nuclear Information System (INIS)

    Dempsey, Mary F.; Condon, Barrie

    2001-01-01

    Most physicians are aware of the absolute contraindications to magnetic resonance imaging (MRI). However, less familiar is the potential for an MRI-induced thermal or electrical burn associated with electrical monitoring devices. Although detailed studies concerning the burn hazard in MRI have not been reported, it is widely believed that direct electromagnetic induction in looped cables associated with the patient is responsible for the excessive heating and it is on this theory that present guidelines are based. Recent reports have however indicated that other mechanisms may cause the heating of metal, either in or on the patient. This document reviews numerous reported burn injuries sustained during MRI and addresses the underlying heating mechanisms possibly causing these events. Dempsey, M.F. and Condon, B. (2001)

  16. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... it may cause some medical devices to malfunction. Most orthopedic implants pose no risk, but you should ... a digital cloud server. Currently, MRI is the most sensitive imaging test of the head (particularly the ...

  17. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... six weeks) before being safe for MRI examinations. Examples include but are not limited to: artificial heart ... the area to be imaged. Furthermore, the examination takes longer than other imaging modalities (typically x-ray ...

  18. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... and may add approximately 15 minutes to the total exam time. top of page What will I ... the limitations of MRI of the Head? High-quality images are assured only if you are able ...

  19. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... distort images of the facial area or brain, so you should let the radiologist know about them. ... MRI units, called short-bore systems , are designed so that the magnet does not completely surround you. ...

  20. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... the head (particularly the brain) in routine clinical practice. top of page What are some common uses ... gadolinium contrast material except when absolutely necessary for medical treatment. See the MRI Safety page for more ...

  1. An fMRI study

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Biosciences; Volume 38; Issue 5 ... Alcoholism; brain; fMRI; language processing; lexical; semantic judgment ... alcohol dependence is associated with neurocognitive deficits in tasks requiring memory, perceptual ...

  2. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... devices or metal in your body. Guidelines about eating and drinking before your exam vary between facilities. ... fitting and has no metal fasteners. Guidelines about eating and drinking before an MRI exam vary with ...

  3. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... to a CD or uploaded to a digital cloud server. Currently, MRI is the most sensitive imaging ... community, you can search the ACR-accredited facilities database . This website does not provide cost information. The ...

  4. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... three to four months of pregnancy unless the potential benefit from the MRI exam is assumed to outweigh the potential risks. Pregnant women should not receive injections of ...

  5. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... for Brain Tumors Radiation Therapy for Head and Neck Cancer Others : American Stroke Association National Stroke Association ... MRA) Magnetic Resonance, Functional (fMRI) - Brain Head and Neck Cancer Treatment Brain Tumor Treatment Magnetic Resonance Imaging ( ...

  6. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... an MRI scan, but this is rare. Tooth fillings and braces usually are not affected by the magnetic field, but they may distort images of the facial area or brain, so you should let the ...

  7. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... is not harmful, but it may cause some medical devices to malfunction. Most orthopedic implants pose no ... Head? Magnetic resonance imaging (MRI) is a noninvasive medical test that physicians use to diagnose medical conditions. ...

  8. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... a CD or uploaded to a digital cloud server. Currently, MRI is the most sensitive imaging test ... understanding of the possible charges you will incur. Web page review process: This Web page is reviewed ...

  9. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... traditional MRI unit is a large cylinder-shaped tube surrounded by a circular magnet. You will lie ... your skin at the site of the IV tube insertion. Some patients may sense a temporary metallic ...

  10. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... metal in your body. Guidelines about eating and drinking before your exam vary between facilities. Unless you ... has no metal fasteners. Guidelines about eating and drinking before an MRI exam vary with the specific ...

  11. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... not use ionizing radiation and may require an injection of a contrast material called gadolinium, which is ... MRI examinations may require you to receive an injection of contrast material into the bloodstream. The radiologist , ...

  12. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... will be removed. MRI exams generally include multiple runs (sequences), some of which may last several minutes. ... top of page Who interprets the results and how do I get them? A radiologist, a physician ...

  13. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... others nearby harm. These items include: jewelry, watches, credit cards and hearing aids, all of which can ... top of page What are the benefits vs. risks? Benefits MRI is a noninvasive imaging technique that ...

  14. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... scanner. top of page How does the procedure work? Unlike conventional x-ray examinations and computed tomography ( ... MRI scanners are air-conditioned and well-lit. Music may be played through the headphones to help ...

  15. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... you should let the radiologist know about them. Parents or family members who accompany patients into the ... intercom. Many MRI centers allow a friend or parent to stay in the room as long as ...

  16. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... to produce detailed pictures of organs, soft tissues, bone and virtually all other internal body structures. MRI ... discovery of abnormalities that might be obscured by bone with other imaging methods. The contrast material used ...

  17. Respiratory challenge MRI: Practical aspects

    Directory of Open Access Journals (Sweden)

    Fiona C. Moreton

    2016-01-01

    Full Text Available Respiratory challenge MRI is the modification of arterial oxygen (PaO2 and/or carbon dioxide (PaCO2 concentration to induce a change in cerebral function or metabolism which is then measured by MRI. Alterations in arterial gas concentrations can lead to profound changes in cerebral haemodynamics which can be studied using a variety of MRI sequences. Whilst such experiments may provide a wealth of information, conducting them can be complex and challenging. In this paper we review the rationale for respiratory challenge MRI including the effects of oxygen and carbon dioxide on the cerebral circulation. We also discuss the planning, equipment, monitoring and techniques that have been used to undertake these experiments. We finally propose some recommendations in this evolving area for conducting these experiments to enhance data quality and comparison between techniques.

  18. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... will hear and feel loud tapping or thumping sounds when the coils that generate the radiofrequency pulses ... use headphones to reduce the intensity of the sounds made by the MRI machine. You may be ...

  19. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... contrast for an MRI. If you have a history of kidney disease or liver transplant, it will ... are not limited to: artificial heart valves implanted drug infusion ports artificial limbs or metallic joint prostheses ...

  20. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... take food and medications as usual. Some MRI examinations may require you to receive an injection of ... for a mild sedative prior to your scheduled examination. Jewelry and other accessories should be left at ...

  1. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... stroke infections developmental anomalies hydrocephalus — dilatation of fluid spaces within the brain (ventricles) causes of epilepsy (seizure) ... MRI. If you have claustrophobia (fear of enclosed spaces) or anxiety, you may want to ask your ...

  2. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... top of page Additional Information and Resources RTAnswers.org : Radiation Therapy for Brain Tumors Radiation Therapy for ... Imaging (MRI) - Head Sponsored by Please note RadiologyInfo.org is not a medical facility. Please contact your ...

  3. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... magnetic field of the MRI unit, metal and electronic items are not allowed in the exam room. ... tell the technologist if you have medical or electronic devices in your body. These objects may interfere ...

  4. MRI of orbital hydroxyapatite implants

    International Nuclear Information System (INIS)

    Flanders, A.E.; De Potter P.; Rao, V.M.; Tom, B.M.; Shields, C.L.; Shields, J.A.

    1996-01-01

    Our aim was to use MRI for the postsurgical assessment of a new form of integrated orbital implant composed of a porous calcium phosphate hydroxyapatite substrate. We studied ten patients 24-74 years of age who underwent enucleation and implantation of a hydroxyapatite ball; 5-13 months after surgery, each patient was examined by spin-echo MRI, with fat suppression and gadolinium enhancement. Fibrovascular ingrowth was demonstrated in all ten patients as areas of enhancement at the periphery of the hydroxyapatite sphere that extended to the center to a variable degree. The radiologist should aware of the MRI appearances of the coralline hydroxyapatite orbital implant since it is now widely used following enucleation. MRI is a useful means to determine successful incorporation of the substrate into the orbital tissues. The normal pattern of contrast enhancement should not be mistaken for recurrent tumor or infection. (orig.)

  5. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... The magnetic field is produced by passing an electric current through wire coils in most MRI units. ... signals that are detected by the coils. The electric current does not come in contact with the ...

  6. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... have any devices or metal in your body. Guidelines about eating and drinking before your exam vary ... is loose-fitting and has no metal fasteners. Guidelines about eating and drinking before an MRI exam ...

  7. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... the head (particularly the brain) in routine clinical practice. top of page What are some common uses ... may follow your regular daily routine and take food and medications as usual. Some MRI examinations may ...

  8. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... can help diagnose conditions such as: brain tumors stroke infections developmental anomalies hydrocephalus — dilatation of fluid spaces ... MRA page for more information. MRI can detect stroke at a very early stage by mapping the ...

  9. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... Most MRI exams are painless. However, some patients find it uncomfortable to remain still during MR imaging. ... anxious, confused or in severe pain, you may find it difficult to lie still during imaging. A ...

  10. MRI of the hip joint

    International Nuclear Information System (INIS)

    Czerny, C.; Noebauer-Huhmann, I.M.; Imhof, H.

    2005-01-01

    Magnetic resonance imaging (MRI) is performed to diagnose many pathologic conditions affecting the hip joint. Either conventional MRI (without contrast enhancement of the joint cavity) or MR arthrography is used to detect and most accurately differentiate hip joint pathologies. Conventional MRI is performed in cases of bone marrow edema, necrosis, arthrosis and especially the so-called ''activated arthrosis'', as well as in inflammatory and tumorous entities. MR arthography, which has only recently become available for use, is excellently suited for diagnosing lesions of the acetabular labrum, cartilage lesions, and free articular bodies. This article provides an overview about MRI characteristics and their accuracy of hip joint diseases and the impact on the therapeutic procedure. (orig.)

  11. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... procedure performed? MRI examinations may be performed on outpatients or inpatients. You will be positioned on the ... and send a signed report to your primary care or referring physician, who will share the results ...

  12. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... As the hydrogen atoms return to their usual alignment, they emit different amounts of energy that vary ... story about radiology? Share your patient story here Images × Image Gallery Magnetic Resonance Imaging (MRI) procedure View ...

  13. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... about pregnancy and MRI. If you have claustrophobia (fear of enclosed spaces) or anxiety, you may want ... also screened for safety in the magnetic environment. Children will be given appropriately sized earplugs or headphones ...

  14. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... used in tattoos may contain iron and could heat up during an MRI scan, but this is ... injection. If you do not require sedation, no recovery period is necessary. You may resume your usual ...

  15. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... MRI exam, a physician, nurse or technologist will insert an intravenous (IV) catheter, also known as an ... physicians with expertise in several radiologic areas. Outside links: For the convenience of our users, RadiologyInfo .org ...

  16. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... used in tattoos may contain iron and could heat up during an MRI scan, but this is ... called MR angiography (MRA) provides detailed images of blood vessels in the brain—often without the need ...

  17. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... bear denotes child-specific content. Related Articles and Media MR Angiography (MRA) Magnetic Resonance, Functional (fMRI) - Brain ... the web pages found at these links. About Us | Contact Us | FAQ | Privacy | Terms of Use | Links | ...

  18. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... you have any devices or metal in your body. Guidelines about eating and drinking before your exam ... soft tissues, bone and virtually all other internal body structures. MRI does not use ionizing radiation (x- ...

  19. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... On very rare occasions, a few patients experience side effects from the contrast material, including nausea, headache and ... structures of the brain and can also provide functional information (fMRI) in selected cases. MR images of ...

  20. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... MRI) of the head uses a powerful magnetic field, radio waves and a computer to produce detailed ... there’s a possibility you are pregnant. The magnetic field is not harmful, but it may cause some ...

  1. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... by the interpreting radiologist. Frequently, the differentiation of abnormal (diseased) tissue from normal tissues is better with ... Tumor Treatment Magnetic Resonance Imaging (MRI) Safety Alzheimer's Disease Head Injury Brain Tumors Images related to Magnetic ...

  2. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... their nature and the strength of the MRI magnet. Many implanted devices will have a pamphlet explaining ... large cylinder-shaped tube surrounded by a circular magnet. You will lie on a moveable examination table ...

  3. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... allergies and whether there’s a possibility you are pregnant. The magnetic field is not harmful, but it ... if there is any possibility that they are pregnant. MRI has been used for scanning patients since ...

  4. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... Examples include but are not limited to: artificial heart valves implanted drug infusion ports artificial limbs or ... imaging based on the electrical activity of the heart, such as electrocardiography (EKG). MRI generally is not ...

  5. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... of many conditions, including tumors. MRI enables the discovery of abnormalities that might be obscured by bone ... Radiology (ACR) and the Radiological Society of North America (RSNA), comprising physicians with expertise in several radiologic ...

  6. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... it is useful to bring that to the attention of the scheduler before the exam and bring ... Image Gallery Magnetic Resonance Imaging (MRI) procedure View full size with caption Pediatric Content Some imaging tests ...

  7. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... MRI scanners are air-conditioned and well-lit. Music may be played through the headphones to help you pass the time. In some cases, intravenous injection of contrast material ...

  8. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... scanner. top of page How does the procedure work? Unlike conventional x-ray examinations and computed tomography ( ... The contrast material used in MRI exams is less likely to produce an allergic reaction than the ...

  9. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... MRI) procedure View full size with caption Pediatric Content Some imaging tests and treatments have special pediatric considerations. The teddy bear denotes child-specific content. Related Articles and Media MR Angiography (MRA) Magnetic ...

  10. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... detailed pictures of the brain and other cranial structures that are clearer and more detailed than other ... tissues, bone and virtually all other internal body structures. MRI does not use ionizing radiation (x-rays). ...

  11. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... contrast for an MRI. If you have a history of kidney disease or liver transplant, it will ... and send a signed report to your primary care or referring physician, who will share the results ...

  12. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... MRI scanners are air-conditioned and well-lit. Music may be played through the headphones to help ... page Additional Information and Resources RTAnswers.org : Radiation Therapy for Brain Tumors Radiation Therapy for Head and ...

  13. Getting an MRI (For Kids)

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    Full Text Available ... site Sitio para adolescentes Body Mind Sexual Health Food & ... RM (video) An MRI (magnetic resonance imaging) scan creates detailed pictures of the inside of the body. The test is painless. All you'll need to do ...

  14. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... structures of the brain and can also provide functional information (fMRI) in selected cases. MR images of the brain and other cranial structures are clearer and more detailed than with other ...

  15. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... are clearer and more detailed than other imaging methods. This exam does not use ionizing radiation and ... clearer and more detailed than with other imaging methods. This detail makes MRI an invaluable tool in ...

  16. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... The magnetic field is produced by passing an electric current through wire coils in most MRI units. Other coils, located in the machine and in some cases, placed around the part ...

  17. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... into the bloodstream. The radiologist , technologist or a nurse may ask if you have allergies of any ... be used in the MRI exam, a physician, nurse or technologist will insert an intravenous (IV) catheter, ...

  18. MRI in bone marrow lesions

    International Nuclear Information System (INIS)

    Linden, A.; Theissen, P.; Schauerte, G.; Schicha, H.; Diehl, V.

    1989-01-01

    MRI has the potential to demonstrate bone marrow pathology due to its good soft tissue contrast. Inflammation and necrosis can be detected very early before there is evidence of radiological changes. In bone tumors intramedullary infiltration can be visualized in addition to soft tissue changes. Metastases of bone and bone marrow, especially in spinal and pelvic regions, are well depicted, often before bone scintigraphy yields pathological findings. In haematological disorders MRI permits follow-up studies due to its good reproducibility. Infiltration by malignant lymphoma and multiple myeloma and its extension in bone marrow can be visualized by MRI, too. However, the most common pathological MRI findings in bone marrow are not very specific, and final diagnosis requires further clinical or histological information. (orig.) [de

  19. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... may follow your regular daily routine and take food and medications as usual. Some MRI examinations may ... to iodine or x-ray contrast material, drugs, food, or the environment, or if you have asthma. ...

  20. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... other imaging methods. This exam does not use ionizing radiation and may require an injection of a contrast ... other internal body structures. MRI does not use ionizing radiation (x-rays). Detailed MR images allow physicians to ...

  1. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... any recent surgeries. Some conditions, such as severe kidney disease, may prevent you from being given gadolinium ... an MRI. If you have a history of kidney disease or liver transplant, it will be necessary ...

  2. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... your regular medications as usual. Leave jewelry at home and wear loose, comfortable clothing. You may be ... Jewelry and other accessories should be left at home, if possible, or removed prior to the MRI ...

  3. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... tissue and fluid, known as edema . MRI typically costs more and may take more time to perform ... accredited facilities database . This website does not provide cost information. The costs for specific medical imaging tests, ...

  4. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... contrast for an MRI. If you have a history of kidney disease or liver transplant, it will ... data suggest that it is safe to continue breastfeeding after receiving intravenous contrast. For further information please ...

  5. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... used in tattoos may contain iron and could heat up during an MRI scan, but this is ... from the contrast material, including nausea, headache and pain at the site of injection. Similarly, patients are ...

  6. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... MRI scanners are air-conditioned and well-lit. Music may be played through the headphones to help ... contrast material in patients with very poor kidney function. Careful assessment of kidney function before considering a ...

  7. Superparamagnetic iron oxides for MRI

    International Nuclear Information System (INIS)

    Weissleder, R.; Reimer, P.

    1993-01-01

    Pharmaceutical iron oxide preparations have been used as MRI contrast agents for a variety of purposes. These agents predominantly decrease T2 relaxation times and therefore cause a decrease in signal intensity of tissues that contain the agent. After intravenous administration, dextran-coated iron oxides typically accumulate in phagocytic cells in liver and spleen. Clinical trials have shown that iron oxide increases lesion/liver and lesion/spleen contrast, that more lesions can be depicted than on plain MRI or CT, and that the size threshold for lesion detection decreases. Decreased uptake of iron oxides in liver has been observed in hepatitis and cirrhosis, potentially allowing the assessment of organ function. More recently a variety of novel, target-specific monocrystalline iron oxides compounds have been used for receptor and immunospecific images. Future development of targeted MRI contrast agents is critical for organ- or tissue-specific quantitative and functional MRI. (orig.)

  8. Superparamagnetic iron oxides for MRI

    Energy Technology Data Exchange (ETDEWEB)

    Weissleder, R [MGH-NMR Center, Dept. of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Reimer, P [MGH-NMR Center, Dept. of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); [Inst. fuer Klinische Radiologie, Zentrale Roentgendiagnostik, Westfaelische-Wilhelms-Univ., Muenster (Germany)

    1993-06-01

    Pharmaceutical iron oxide preparations have been used as MRI contrast agents for a variety of purposes. These agents predominantly decrease T2 relaxation times and therefore cause a decrease in signal intensity of tissues that contain the agent. After intravenous administration, dextran-coated iron oxides typically accumulate in phagocytic cells in liver and spleen. Clinical trials have shown that iron oxide increases lesion/liver and lesion/spleen contrast, that more lesions can be depicted than on plain MRI or CT, and that the size threshold for lesion detection decreases. Decreased uptake of iron oxides in liver has been observed in hepatitis and cirrhosis, potentially allowing the assessment of organ function. More recently a variety of novel, target-specific monocrystalline iron oxides compounds have been used for receptor and immunospecific images. Future development of targeted MRI contrast agents is critical for organ- or tissue-specific quantitative and functional MRI. (orig.)

  9. MRI of cerebral alveolar echinococcosis

    International Nuclear Information System (INIS)

    Tunaci, M.; Tunaci, A.; Engin, G.; Oezkorkmaz, B.; Ahishali, B.; Rozanes, I.

    1999-01-01

    Cerebral alveolar echinococcosis is rare. We report a case with multiple intracranial masses which show cauliflower-like contrast enhancement pattern on MRI. The lesions originated from hepatic involvement with invasion of the inferior vena cava. (orig.)

  10. Getting an MRI (For Kids)

    Medline Plus

    Full Text Available ... resonancia magnética, RM (video) An MRI (magnetic resonance imaging) scan creates detailed pictures ... educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor. © 1995- ...

  11. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... MRI. For more information, consult your radiologist. The computer workstation that processes the imaging information is located ... not come in contact with the patient. A computer then processes the signals and generates a series ...

  12. Magnetic Resonance Imaging (MRI) -- Head

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    Full Text Available ... it is useful to bring that to the attention of the scheduler before the exam and bring ... bore which can be more comfortable for larger size patients or patients with claustrophobia. Other MRI machines ...

  13. MRI in diagnosis of spinal cord diseases

    International Nuclear Information System (INIS)

    Kobayashi, Naotoshi; Ono, Yuko; Kakinoki, Yoshio; Kimura, Humiko; Ebihara, Reiko; Nagayama, Takashi; Okada, Takaharu; Watanabe, Hiromi

    1985-01-01

    64 MRI studies of 57 cases of spinal cord diseases were reviewed, and following results were obtained. (1) MRI is usefull for screening method of spinal cord diseases, as CT in cerebral diseases. (2) MRI might replaces myelography in most of spinal cord disease, and more reliable informations might be obtained by MRI than in myelography in some cases, but (3) in detection of small organic changes, some technological problems are layed regarding to the image resolution of MRI. (author)

  14. Clinical application of functional MRI

    International Nuclear Information System (INIS)

    Taniwaki, Takayuki

    2010-01-01

    Described is the present state of clinical application of fMRI in the preoperative assessment of brain tumors, and plasticity in and pathophysiology of central diseases. For the tumor resection, fMRI is useful for risk assessment of postoperative nerve dysfunction, for selection of the patient rather suitable for brain mapping at the invasive surgery than at the pre-operation and for guidance of the operation itself. Preoperative fMRI alone can neither distinguish the regions of the primary and secondary functions nor exhibit the relation between the tumor and white matter fibers but there are compensatory means for these drawbacks. Benefit of preoperative fMRI has not yet been based on the evidence on double blind trials. Combination of fMRI imaging and electroencephalography (EEG) finding has shown that, in generalized epilepsy, extensive and stimulated activation occurs in both frontal/occipital regions and in thalamus area, respectively, and that the concomitant lowered activities are conceivably the reflection of burst discharge in normal brain functions. Plasticity in the human brain has been demonstrated by fMRI in cerebral vascular diseases, multiple sclerosis and amyotrophic lateral sclerosis. Pathogenesis of Parkinson disease and depression has been better understood by fMRI investigations revealing regions with elevated and reduced activities. Studies of attention deficit hyperactivity disorder have shown similar change of activities with functional reductions of the right dorsolateral frontal anterior area and of dorsal frontal cingulate gyrus, together with stimulated wider regions to given tasks. As above, fMRI has greatly contributed to our understanding of diseases of central nervous system and is to be expected to expand wider in this field. (T.T.)

  15. MRI in acute disseminated encephalomyelitis

    International Nuclear Information System (INIS)

    Caldemeyer, K.S.; Smith, R.R.; Harris, T.M.; Edwards, M.K.

    1994-01-01

    A retrospective analysis of CT and MRI studies in 12 patients with a clinical diagnosis of acute disseminated encephalomyelitis (ADEM) was performed. MRI was the definitive modality for the assessment of the lesions of ADEM: all patients had abnormalities consistent with the clinical diagnosis. Ten had abnormalities in the brain, three spinal cord lesions, and three showed evidence of optic neuritis. CT was normal in 6 of the 7 patients in which it was performed. (orig.)

  16. MRI and intraocular tamponade media

    International Nuclear Information System (INIS)

    Manfre, I.; Fabbri, G.; Avitabile, T.; Biondi, P.; Reibaldi, A.; Pero, G.

    1993-01-01

    Thirteen patients who underwent surgery for retinal detachment and injection of intraocular tamponade media (silicone oil, flurosilicone oil, or perfluoro-carbon liquid) underwent magnetic resonance imaging (MRI), using spin-echo T1- and T2-weighted images. The ophthalmic tamponade media showed different signal intensity, according to their chemical structure. Unlike ophthalmoscopy or ultrasonography, MRI showed no oil-related artefact, making possible recognition of recurrent retinal detachment. (orig.)

  17. MRI and intraocular tamponade media

    Energy Technology Data Exchange (ETDEWEB)

    Manfre, I. (Dept. of Neuroradiology, Inst. of Neurosurgery, Univ. of Catania (Italy)); Fabbri, G. (Dept. of Neuroradiology, Inst. of Neurosurgery, Univ. of Catania (Italy)); Avitabile, T. (Inst. of Ophthalmology, Univ. of Catania (Italy)); Biondi, P. (Inst. of Ophthalmology, Univ. of Catania (Italy)); Reibaldi, A. (Inst. of Ophthalmology, Univ. of Catania (Italy)); Pero, G. (Dept. of Neuroradiology, Inst. of Neurosurgery, Univ. of Catania (Italy))

    1993-05-01

    Thirteen patients who underwent surgery for retinal detachment and injection of intraocular tamponade media (silicone oil, flurosilicone oil, or perfluoro-carbon liquid) underwent magnetic resonance imaging (MRI), using spin-echo T1- and T2-weighted images. The ophthalmic tamponade media showed different signal intensity, according to their chemical structure. Unlike ophthalmoscopy or ultrasonography, MRI showed no oil-related artefact, making possible recognition of recurrent retinal detachment. (orig.)

  18. MRI in ocular drug delivery

    OpenAIRE

    Li, S. Kevin; Lizak, Martin J.; Jeong, Eun-Kee

    2008-01-01

    Conventional pharmacokinetic methods for studying ocular drug delivery are invasive and cannot be conveniently applied to humans. The advancement of MRI technology has provided new opportunities in ocular drug-delivery research. MRI provides a means to non-invasively and continuously monitor ocular drug-delivery systems with a contrast agent or compound labeled with a contrast agent. It is a useful technique in pharmacokinetic studies, evaluation of drug-delivery methods, and drug-delivery de...

  19. [Recent advances in newborn MRI].

    Science.gov (United States)

    Morel, B; Hornoy, P; Husson, B; Bloch, I; Adamsbaum, C

    2014-07-01

    The accurate morphological exploration of the brain is a major challenge in neonatology that advances in magnetic resonance imaging (MRI) can now provide. MRI is the gold standard if an hypoxic ischemic pathology is suspected in a full term neonate. In prematures, the specific role of MRI remains to be defined, secondary to US in any case. We present a state of the art of hardware and software technical developments in MRI. The increase in magnetic field strength (3 tesla) and the emergence of new MRI sequences provide access to new information. They both have positive and negative consequences on the daily clinical data acquisition use. The semiology of brain imaging in full term newborns and prematures is more extensive and complex and thereby more difficult to interpret. The segmentation of different brain structures in the newborn, even very premature, is now available. It is now possible to dissociate the cortex and basal ganglia from the cerebral white matter, to calculate the volume of anatomical structures, which improves the morphometric quantification and the understanding of the normal and abnormal brain development. MRI is a powerful tool to analyze the neonatal brain. The relevance of the diagnostic contribution requires an adaptation of the parameters of the sequences to acquire and of the image processing methods. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  20. Nanomaterials and MRI molecular probe

    International Nuclear Information System (INIS)

    Inubushi, Toshiro

    2008-01-01

    This paper presents the current state and future prospect of enhancing probes in MRI which enable to image specific cells and molecules mainly from the aspect of cell trafficking. Although MRI requires such probes for specific imaging, it has an advantage that anatomical images are simultaneously available even during surgical operation without radiation exposure, differing from X-CT, -transillumination and positron emission tomography (PET). In the development of novel MRI molecular probes, the recent topic concerns the cell trafficking biology where cells related with transplantation and immunological therapy can be traced. Although superparamagnetic iron oxide (SPIO) has been used as a commercially available enhancer, this nanoparticle has problems like a difficulty to penetrate cell, cytotoxicity and others. For these, authors have developed the nanoparticle SPIO covered with silica shell, which can be chemically modified, e.g., by binding fluorescent pigments to possibly allow MR bimodal molecular imaging. For penetration of particles in cells, envelop of Sendai virus is used. PET-CT has been more popular these days; however, MRI is superior to CT for imaging soft tissues, and development of PET-MRI is actively under progress aiming the multi-modal imaging. At present, molecular probes for MRI are certainly not so many as those for PET and cooperative efforts to develop the probes are required in medical, technological and pharmaceutical fields. (R.T.)

  1. MRI diagnosis of eyeball diseases

    International Nuclear Information System (INIS)

    Tao Xiaofeng; Shi Zengru; Xiao Xiangsheng; Yu Hong; Wei Ruili

    2003-01-01

    Objective: To review the MR imaging of eyeball mass in 75 patients with the intention to enhance the acknowledgement to eyeball diseases. Methods: Seventy-five patients, 45 males and 30 females, were examined with MRI before treatment. Most MRI studies were performed with head coil and a few with orbit surface coil. Sagittal, coronal, and axial images were attained. Enhanced MRI studies were performed in 37 cases. High magnetic field MRI studies were performed with additional fat saturation technique. Results: Retinoblastoma (20 cases) showed isointensity in 11 and low signal intensity in 9 on T 1 WI, and isointensity in 5 and slight high signal in 15 on T 2 WI. Coats' disease (5 cases) involved single eyeball in all cases without calcification or eyeball enlargement, and presented as slight high signal on T 1 WI and high signal on T 2 WI. Choroidal angioma (3 cases) showed slight high signal on T 1 WI and high signal on T 2 WI. Metastasis (20 cases) was located in the posterior wall of the eyeball. Extra-global invasion occurred in 8 cases and intra-global invasion in 20. Marked thickening of the global wall with isointensity (8 cases) or low signal intensity (12 cases) was detected on T 1 WI, and isointensity (6 cases) or slight high signal intensity (14 cases) was demonstrated on T 2 WI. Marked enhancement was revealed in all 15 cases. Melanoma (7 cases) showed high signal intensity (5) and isointensity (2) on T 1 WI, and low signal (7) on T 2 WI. Retinal detachment (19 cases) showed high signal on both T 1 and T 2 WI, etc. In the diagnosis of eyeball diseases with MRI, the total sensitivity was 100% and specificity was 86.7%. Conclusions: MRI imaging is an important examination method to eyeball diseases, and most diagnosis and differential diagnosis of eyeball diseases can be made correctly with MRI

  2. Dementia: role of MRI

    International Nuclear Information System (INIS)

    Georgieva-Kozarova, G.

    2012-01-01

    Full text: This presentation will focus on the role of MRI in the diagnosis of dementia and related diseases. We will discuss the following subjects: 1. Systematic assessment of MR in dementia 2. MR protocol for dementia 3. Typical findings in the most common dementia syndrome Alzheimer's disease (AD), Vascular Dementia (VaD), Frontotemporal lobe dementia (FTLD) 4. Short overview of neurodegenerative disorders which may be associated with dementia. The role of neuroimaging in dementia nowadays extends to support the diagnosis of specific neurodegenerative disorders. It is a challenge to the early diagnosis of neurodegenerative diseases such as Alzheimer's disease. Early diagnosis includes recognition of predementia conditions, such as mild cognitive impairment (MCI). Neuroimaging may also be used to assess disease progression and is adopted in current trials investigating MCI and AD. An MR-study of a patient suspected of having dementia must be assessed in a standardized way. First of all, treatable diseases like subdural hematomas, tumors and hydrocephalus need to be excluded. Next we should look for signs of specific dementias such as: Alzheimer's disease (AD): medial temporal lobe atrophy (MTA) and parietal atrophy. Frontotemporal Lobar Degeneration (FTLD): (asymmetric) frontal lobe atrophy and atrophy of the temporal pole. Vascular Dementia (VaD): global atrophy, diffuse white matter lesions, lacunas and 'strategic infarcts' (infarcts in regions that are involved in cognitive function). Dementia with Lewy bodies (DLB): in contrast to other forms of dementia usually no specific abnormalities. So when we study the MR images we should score in a systematic way for global atrophy, focal atrophy and for vascular disease (i.e. infarcts, white matter lesions, lacunas)

  3. MRI in patients with general paresis

    International Nuclear Information System (INIS)

    Zifko, U.; Wimberger, D.; Lindner, K.; Zier, G.; Grisold, W.; Schindler, E.

    1996-01-01

    Few cases of MRI in neurosyphilis have been reported. We examined the value of MRI in patients with general paresis; MRI was performed on four HIV-negative patients with parenchymatous neurosyphilis. It demonstrated frontal and temporal atrophy, subcortical gliosis and, in one patient, increased ferritin in the basal ganglia. The progression of the lesions on MRI correlated well with the neuropsychiatric disturbances. The MRI findings correlated with the wellknown neuropathological findings. This combination of pathological findings in neurosyphilis has not been described before and we suggest that MRI is of prognostic value in patients with general paresis. (orig.)

  4. Whole-body MRI screening

    Energy Technology Data Exchange (ETDEWEB)

    Puls, Ralf [HELIOS Klinikum Erfurt (Germany). Inst. of Diagnostic and Interventional Radiology and Neuroradiology; Hosten, Norbert (ed.) [Universitaetsklinikum Greifswald (Germany). Diagnostic Radiology and Neuroradiology

    2014-07-01

    The advent of dedicated whole-body MRI scanners has made it possible to image the human body from head to toe with excellent spatial resolution and with the sensitivity and specificity of conventional MR systems. A comprehensive screening examination by MRI relies on fast image acquisition, and this is now feasible owing to several very recent developments, including multichannel techniques, new surface coil systems, and automatic table movement. The daily analysis of whole-body MRI datasets uncovers many incidental findings, which are discussed by an interdisciplinary advisory board of physicians from all specialties. This book provides a systematic overview of these incidental findings with the aid of approximately 240 high-quality images. The radiologists involved in the project have written chapters on each organ system, presenting a structured compilation of the most common findings, their morphologic appearances on whole-body MRI, and guidance on their clinical management. Chapters on technical and ethical issues are also included. It is hoped that this book will assist other diagnosticians in deciding how to handle the most common incidental findings encountered when performing whole-body MRI.

  5. MRI in ischemic brain diseases

    International Nuclear Information System (INIS)

    Steinbrich, W.; Friedmann, G.; Pawlik, G.; Boecher-Schwarz, H.G.; Heiss, W.D.

    1986-01-01

    The results of MRI and CT in 55 patients with brain infarcts were compared; in 26 of these cases an additional PET examination was obtained in order to study the regional glucose utilisation. MRI was superior to CT, demonstrating 11% more of the infarcts, particularly during the first 24 hours, in small lesions confined to the grey or subcortical white matter and in infratentorial ischemic lesion. On the other hand, only CT was able to show fresh hemorrhage, although MRI was the method of choice to demonstrate old blood collections. To characterise the follow up of an infarct, CT and MRI were similar, except the marginal contrast enhancement sometimes demonstrated by CT studies between the 2nd and 4th week after stroke event. PET was inferior to show details because of its poorer spatial resolution, but anyhow had a high sensitivity and provided additional informations concerning secondary inactivations of brain areas not directly damaged. Additionally PET was able to demonstrate areas of anaerobic glycolysis and lesions of diminished glucose utilisation in TIAs. Small areas of gliosis in the white matter of the cerebral hemispheres were frequently found in patients with cerebro-vascular diseases; they were best shown by MRI, but do not correlate with the extent of vascular stenoses or occlusions, shown by angiography. (orig) [de

  6. FAST MRI breast screening revisited

    International Nuclear Information System (INIS)

    Jain, Manish; Jain, Arushi; Hyzy, Marek D.; Werth, Graziella

    2017-01-01

    Screening for breast cancer in high-risk women takes about 40 minutes to acquire an MRI scan and is time-intensive to report. There is recent interest in the performance of an abbreviated MRI protocol (FAST) in the screening setting. FAST scans have a reported negative predictive value of 99.8%. This study evaluates the false positive rates (FPR) and recall rates for FAST scans as compared to full diagnostic studies (FD). A database of all screening breast MRI scans performed at our institution between 30 June 2013 and 1 July 2014 (n = 591) was created by one of the researchers, who did not subsequently analyse the MRI scans. The T1W and first post-contrast and subtracted images from each of these scans (FAST protocol) were assessed by experienced breast MRI radiologists, blinded to the final diagnosis. The findings were then compared with the FD result. The recall rates were 6.6% for FAST scans and 5.8% for FD scans. FPR rates were 4.7% and 3.9% respectively. There is no statistically significant difference in the recall rates or FPR of FAST scans in comparison with full diagnostic studies. Given the absence of statistically significant difference in the FPR and recall rates in comparison with FD, FAST scans can replace FD for screening of breast cancer.

  7. Whole-body MRI screening

    International Nuclear Information System (INIS)

    Puls, Ralf; Hosten, Norbert

    2014-01-01

    The advent of dedicated whole-body MRI scanners has made it possible to image the human body from head to toe with excellent spatial resolution and with the sensitivity and specificity of conventional MR systems. A comprehensive screening examination by MRI relies on fast image acquisition, and this is now feasible owing to several very recent developments, including multichannel techniques, new surface coil systems, and automatic table movement. The daily analysis of whole-body MRI datasets uncovers many incidental findings, which are discussed by an interdisciplinary advisory board of physicians from all specialties. This book provides a systematic overview of these incidental findings with the aid of approximately 240 high-quality images. The radiologists involved in the project have written chapters on each organ system, presenting a structured compilation of the most common findings, their morphologic appearances on whole-body MRI, and guidance on their clinical management. Chapters on technical and ethical issues are also included. It is hoped that this book will assist other diagnosticians in deciding how to handle the most common incidental findings encountered when performing whole-body MRI.

  8. MRI diagnosis of meniscal tears

    International Nuclear Information System (INIS)

    Kuga, Naoyuki; Oh, Toshihiro

    1996-01-01

    We studied the accuracy of magnetic resonance imaging (MRI) of the knee in fifty-six patients who were also examined arthroscopically. The accuracy, sensitivity, and specificity were 96%, 100%, and 95% for medial meniscal tears, and 91%, 67%, and 100% for lateral meniscal tears respectively. Two MRIs of the medial meniscus were false-positives. These MRI findings were both meniscocapsular separation of the medial meniscus, but the arthroscopic findings were normal. One case was an ACL injury and the other PCL and MCL injury. Hemorrhage and edema of the medial capsule caused by valgus stress at injury may look like a meniscal pseudo-tear on MRI. Five MRIs of the lateral meniscus were false-negatives. All menisci showed normal signal and shape on MRI but traumatic and stable tears of the lateral meniscus were identified arthroscopically. All were associated with ACL tears and lateral condylar bone bruise. The traumatic and stable tear of the meniscus tended to be overlooked on MRI because a meniscus without degeneration shows a normal signal. (author)

  9. MRI experiments for introductory physics

    Science.gov (United States)

    Taghizadeh, Sanaz; Lincoln, James

    2018-04-01

    The introductory physics classroom has long educated students about the properties of the atom and the nucleus. But absent from these lessons has been an informed discussion of magnetic resonance imaging (MRI) and its parent science nuclear magnetic resonance (NMR). Physics teachers should not miss the opportunity to instruct upon this highly relevant application of modern physics, especially with so many of our students planning to pursue a career in medicine. This article provides an overview of the physics of MRI and gives advice on how physics teachers can introduce this topic. Also included are some demonstration activities and a discussion of a desktop MRI apparatus that may be used by students in the lab or as a demo.

  10. Superconducting magnet systems for MRI

    International Nuclear Information System (INIS)

    Hawksworth, D.G.

    1988-01-01

    MRI is the first large scale commercial application of superconductivity and has not achieved the status of a mature industry with an annual turnover in the magnet industry alone in excess of $150M. Conservative estimates put the investment of the medical industry in MRI as a whole at more than a billion dollars. In the nine years since shipment of the first superconducting whole body imaging magnets of 0.3 Tesla field the standard product of the industry has become a system of 1 meter bore and field strength 0.5 Tesla to 1.5 Tesla. In this paper the evolution of present day MRI magnets from small bore but high field spectrometer magnets is reviewed and the direction of future developments discussed

  11. Computational Diffusion MRI : MICCAI Workshop

    CERN Document Server

    Grussu, Francesco; Ning, Lipeng; Tax, Chantal; Veraart, Jelle

    2018-01-01

    This volume presents the latest developments in the highly active and rapidly growing field of diffusion MRI. The reader will find numerous contributions covering a broad range of topics, from the mathematical foundations of the diffusion process and signal generation, to new computational methods and estimation techniques for the in-vivo recovery of microstructural and connectivity features, as well as frontline applications in neuroscience research and clinical practice. These proceedings contain the papers presented at the 2017 MICCAI Workshop on Computational Diffusion MRI (CDMRI’17) held in Québec, Canada on September 10, 2017, sharing new perspectives on the most recent research challenges for those currently working in the field, but also offering a valuable starting point for anyone interested in learning computational techniques in diffusion MRI. This book includes rigorous mathematical derivations, a large number of rich, full-colour visualisations and clinically relevant results. As such, it wil...

  12. MRI of neuronal migration disorders

    International Nuclear Information System (INIS)

    Engelbrecht, V.

    1996-01-01

    Twenty-one MRI examinations of the brain were performed in 19 children with neuronal migration disorders. Multiplanar oriented spin-echo sequences were on a scanner with 1.5 T. In 8 children we performed an additional turbo-inversion recovery (TIR) sequence. Results of sonography or CT from five children were compared with MRI scans. Using the actual nomenclature, we found the following migration disorders: Lissencephaly (n=6), cobblestone lissencephaly with Walker-Warbung syndrome (WWS) (n=2), polymicrogyria and schizencephaly (n=2), focal heterotopia (n=5), diffuse heterotopie (n=2) and hemimegalencephaly (n=2). MRI was superior to CT and sonography in all children. Except for the two boys with WWS, the TIR sequence was the best to demonstrate the changes in migration disorder because of the high contrast between gray and white matter. We demonstrate the characteristic features of the different migration disorders and compare them with the existing literature. (orig.) [de

  13. Complex Wavelet transform for MRI

    International Nuclear Information System (INIS)

    Junor, P.; Janney, P.

    2004-01-01

    Full text: There is a perpetual compromise encountered in magnetic resonance (MRl) image reconstruction, between the traditional elements of image quality (noise, spatial resolution and contrast). Additional factors exacerbating this trade-off include various artifacts, computational (and hence time-dependent) overhead, and financial expense. This paper outlines a new approach to the problem of minimizing MRI image acquisition and reconstruction time without compromising resolution and noise reduction. The standard approaches for reconstructing magnetic resonance (MRI) images from raw data (which rely on relatively conventional signal processing) have matured but there are a number of challenges which limit their use. A major one is the 'intrinsic' signal-to-noise ratio (SNR) of the reconstructed image that depends on the strength of the main field. A typical clinical MRI almost invariably uses a super-cooled magnet in order to achieve a high field strength. The ongoing running cost of these super-cooled magnets prompts consideration of alternative magnet systems for use in MRIs for developing countries and in some remote regional installations. The decrease in image quality from using lower field strength magnets can be addressed by improvements in signal processing strategies. Conversely, improved signal processing will obviously benefit the current conventional field strength MRI machines. Moreover, the 'waiting time' experienced in many MR sequences (due to the relaxation time delays) can be exploited by more rigorous processing of the MR signals. Acquisition often needs to be repeated so that coherent averaging may partially redress the shortfall in SNR, at the expense of further delay. Wavelet transforms have been used in MRI as an alternative for encoding and denoising for over a decade. These have not supplanted the traditional Fourier transform methods that have long been the mainstay of MRI reconstruction, but have some inflexibility. The dual

  14. Interstitial pregnancy: role of MRI

    International Nuclear Information System (INIS)

    Filhastre, M.; Lesnik, A.; Dechaud, H.; Taourel, P.

    2005-01-01

    We report the MRI features of two cases of interstitial pregnancy. In both cases, MRI was able to localize the ectopic pregnancy by showing a gestational structure surrounded by a thick wall in the upper part of the uterine wall separated from the endometrium by an uninterrupted junctional zone. Because US may confuse angular and interstitial pregnancies and because interstitial pregnancy has a particular evolutive course, MR imaging may play a key role in the diagnosis and management of women with interstitial pregnancy. (orig.)

  15. MRI imaging in pediatric appendicitis

    Directory of Open Access Journals (Sweden)

    Robin Riley

    2018-04-01

    Full Text Available An 8-year-old male presents with two days of abdominal pain and emesis. Computed tomography was concerning for obstruction or reactive ileus with an apparent transition point in the right lower quadrant, possibly due to Crohn's. Magnetic resonance imaging was concerning for perforated appendicitis. As demonstrated by this case MRI can be as sensitive as CT in detecting pediatric appendicitis [2]. We recommend using MRI instead of CT to diagnose appendicitis to avoid ionizing radiation and increased cancer risk in the pediatric population. Keywords: Computer tomography, Magnetic resonance imaging, Pediatric appendicitis

  16. MRI of focal cortical dysplasia

    International Nuclear Information System (INIS)

    Lee, B.C.P.; Hatfield, G.A.; Bourgeois, B.; Park, T.S.

    1998-01-01

    We studied nine cases of focal cortical dysplasia (FCD) by MRI, with surface-rendered 3D reconstructions. One case was also examined using single-voxel proton MR spectroscopy (MRS). The histological features were reviewed and correlated with the MRI findings. The gyri affected by FCD were enlarged and the signal of the cortex was slightly increased on T1-weighted images. The gray-white junction was indistinct. Signal from the subcortical white matter was decreased on T1- and increased on T2-weighted images in most cases. Contrast enhancement was seen in two cases. Proton MRS showed a spectrum identical to that of normal brain. (orig.) (orig.)

  17. MRI of the foetal brain

    International Nuclear Information System (INIS)

    Rich, P.; Jones, R.; Britton, J.; Foote, S.; Thilaganathan, B.

    2007-01-01

    Ultrasound examinations for foetal brain abnormalities have been a part of the routine antenatal screening programme in the UK for many years. In utero brain magnetic resonance imaging (MRI) is now being used increasingly successfully to clarify abnormal ultrasound findings, often resulting in a change of diagnosis or treatment plan. Interpretation requires an understanding of foetal brain development, malformations and acquired diseases. In this paper we will outline the technique of foetal MRI, relevant aspects of brain development and provide illustrated examples of foetal brain pathology

  18. Magnetic Resonance Imaging (MRI): Dynamic Pelvic Floor

    Science.gov (United States)

    ... to a CD or uploaded to a digital cloud server. Dynamic pelvic floor MRI provides detailed pictures ... with you. top of page What are the benefits vs. risks? Benefits MRI is a noninvasive imaging ...

  19. Magnetic Resonance Imaging (MRI): Brain (For Parents)

    Science.gov (United States)

    ... Staying Safe Videos for Educators Search English Español Magnetic Resonance Imaging (MRI): Brain KidsHealth / For Parents / Magnetic Resonance Imaging (MRI): Brain What's in this article? What ...

  20. MRI of intracranial meningeal malignant fibrous histiocytoma

    International Nuclear Information System (INIS)

    Ogino, A.; Ochi, M.; Hayashi, K.; Hirata, K.; Hayashi, T.; Yasunaga, A.; Shibata, S.

    1996-01-01

    We describe the CT and MRI findings in a patient with primary intracranial meningeal malignant fibrous histiocytoma (MFH). CT delineated the anatomical relations and MRI aided in tissue characterisation. To our knowledge, this is the first report describing the MRI findings in primary intracranial meningeal MFH. (orig.). With 1 fig

  1. 'Unusual' MRI appearance of sphenoid sinus mucocele

    International Nuclear Information System (INIS)

    Ruelle, A.; Pisani, R.; Andrioli, G.

    1991-01-01

    The authors report a case of sphenoid sinus mucocele which exhibited unusual MRI features. However a review of the literature shows that these lesions may present with different MRI appearances probably related to the variability of the cyst content. Further series are needed for a better definition of the MRI behaviour of the lesions. (orig.)

  2. Practical aspects of MRI of the prostate

    Directory of Open Access Journals (Sweden)

    Dragoș Cuzino

    2014-12-01

    Full Text Available The article presents the main aspects of sectional anatomy, lymph nodes and adjacent structures as well as MRI examination standard protocol for prostate cancer diagnosis. Using MRI multiparametric examination we succeed in classifying efficiently the malignant prostatic tumors using PI- RADS system. Also, using MRI multiparametric examination we can evaluate the effectiveness of prostate cancer treatment

  3. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... types of clips used for brain aneurysms some types of metal coils placed within blood vessels nearly all cardiac defibrillators and pacemakers You ... called MR angiography (MRA) provides detailed images of blood vessels in the ... the opening of certain types of MRI machines. The presence of an implant ...

  4. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... procedure work? How is the procedure performed? What will I experience during and after the procedure? Who interprets the results and how do I get them? What are the benefits vs. risks? What are the limitations of MRI ...

  5. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician Resources Professions Site Index A-Z Magnetic Resonance Imaging (MRI) - ...

  6. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... have allergies of any kind, such as an allergy to iodine or x-ray contrast material, drugs, food, or the environment, or if you have asthma. The contrast material most commonly used for an MRI exam contains a metal ... in patients with iodine contrast allergy. It is far less common for a patient ...

  7. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... provides detailed images of blood vessels in the brain—often without the need for contrast material. See the MRA page for more information. MRI can detect stroke at a very early stage by mapping the motion of water molecules in the tissue. ...

  8. MRI findings in cranial eumycetoma

    International Nuclear Information System (INIS)

    Ahmed, Munawwar; Sureka, Jyoti; Chacko, Geeta; Eapen, Anu

    2011-01-01

    Cranial eumycetoma (CE) due to direct inoculation of Madurella grisea into the scalp is extremely rare. We describe a case of CE caused by direct inoculation of M. grisea with the characteristic MRI findings of the “dot-in-circle” sign and a conglomeration of multiple, extremely hypointense “dots.”

  9. Getting an MRI (For Kids)

    Medline Plus

    Full Text Available ... Answers (Q&A) Staying Safe Videos for Educators Search English Español Getting an MRI (Video) KidsHealth / For ... Nondiscrimination Visit the Nemours Web site. Note: All information on KidsHealth® is for educational purposes only. For ...

  10. MRI-induced retrocalcaneal bursitis

    NARCIS (Netherlands)

    Tol, J. L.; van Dijk, C. N.; Maas, M.

    1999-01-01

    This case report describes a patient with acute retrocalcaneal bursitis, which developed after MRI examination of the ankle. The sagittal T2*-weighted gradient echo sequence revealed an extensive susceptibility artifact in the area surrounding the Achilles tendon near its insertion at the os calcis.

  11. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... internal body structures. MRI does not use ionizing radiation (x-rays). Detailed MR images allow physicians to evaluate various ... kind, such as an allergy to iodine or x-ray contrast material, drugs, food, or the environment, or ...

  12. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... very early stage by mapping the motion of water molecules in the tissue. This water motion, known as diffusion, is impaired by most ... the limitations of MRI of the Head? High-quality images are assured only if you are able ...

  13. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... of which shows a thin slice of the body. The images can then be studied from different angles by ... information please consult the ACR Manual on Contrast Media and its references. top of page What are the limitations of MRI of the Head? High-quality images are assured only if you are able to ...

  14. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... also screened for safety in the magnetic environment. Children will be given appropriately sized earplugs or headphones during the exam. MRI scanners are air-conditioned and well-lit. Music may be played through the headphones to help ...

  15. MRI in recurrent nasopharyngeal carcinoma

    International Nuclear Information System (INIS)

    Ng, S.H.; Ko, S.F.; Wan, Y.L.; Chang, J.T.C.; Chen, W.C.; Tang, L.M.

    1999-01-01

    In this study, we retrospectively reviewed the MRI features of recurrent nasopharyngeal carcinoma (NPC) in 72 patients who underwent MRI before and after gadolinium injection. Recurrent NPC exhibited a high degree of regional spread and a variety of signal intensities and contours. MRI showed a nasopharyngeal mass in 50 patients (69.4 %); other sites of involvement included the parapharyngeal space (44.4 %), nasal cavity (12.5 %), paranasal sinuses (27.8 %), oropharynx (4.2 %), orbit (8.3 %), infratemporal fossa (18.1 %), skull base (59.8 %), intracranial area (51.4 %) and regional lymph nodes (15.3 %). On T2-weighted images, the nasopharyngeal mass gave high signal in 9 of 50 cases (18 %), intermediate in 27 (54 %), mixed in 8 (16 %) and low signal in 6 (12 %). Contrast enhancement was strong in 12 cases (24 %), moderate in 29 (58 %) and heterogeneous in 9 (18 %). The lesion was convex in 31 cases (62 %) and concave or straight in 19 (38 %). Recognition of the distribution and the appearance of recurrent NPC on MRI is essential for timely diagnosis and appropriate treatment. (orig.)

  16. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... to have an allergy to a gadolinium-based contrast agent used for MRI than the iodine-containing contrast ... more information on adverse reactions to gadolinium-based contrast agents, please consult the ACR Manual on Contrast Media . ...

  17. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... which they come. The MR scanner captures this energy and creates a picture of the tissues scanned based on this information. The magnetic field is produced by passing an electric current through wire coils in most MRI units. ...

  18. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... body structures. MRI does not use ionizing radiation (x-rays). Detailed MR images allow physicians to evaluate various ... kind, such as an allergy to iodine or x-ray contrast material, drugs, food, or the environment, or ...

  19. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... contrast for an MRI. If you have a history of kidney disease or liver transplant, it will be necessary to perform a blood test to determine whether the kidneys are functioning adequately. Women should always inform their physician or technologist if ...

  20. MRI in distal vaginal atresia

    International Nuclear Information System (INIS)

    Hugosson, C.; Jorulf, H.; Bakri, Y.

    1991-01-01

    Magnetric resonance imaging in two young females with abdominal pain revealed vaginal atresia with massive hematocolpos but a normal cervix and uterine body. Information obtained with MRI was superior to ultrasound and CT and is suggested as the examination of choice prior to surgical correction. (orig.)

  1. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us ... the equipment look like? How does the procedure work? How is the ... use to diagnose medical conditions. MRI uses a powerful magnetic field, radio frequency ...

  2. Congenital bronchobiliary fistula: MRI appearance

    International Nuclear Information System (INIS)

    Hourigan, Jon S.; Carr, Michael G.; Burton, Edward M.; Ledbetter, Joel C.

    2004-01-01

    Congenital bronchobiliary fistula (CBBF) is a rare anomaly. Twenty-three cases have been reported since the anomaly was first described in 1952. Most of these cases were diagnosed by bronchoscopy, cholangiography, or hepatobiliary nuclear imaging. Our case of a newborn with bilious emesis with CBBF was depicted by T1-weighted gradient-echo MRI sequences. (orig.)

  3. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... able to see, hear and speak with you at all times using a two-way intercom. Many MRI centers allow a friend or parent to stay in the room as long as they are also screened for safety in the magnetic environment. Children will be given ...

  4. MRI of medulloblastoma in adults

    International Nuclear Information System (INIS)

    Malheiros, S.M.F.; Santos, A.J.; Borges, L.R.R.; Guimaraes, I.F.; Franco, C.M.R.; Gabbai, A.A.; Carrete, H.; Stavale, J.N.; Pelaez, M.P.

    2003-01-01

    Medulloblastoma has variable appearances on MRI in both children and adults. Adults are more likely to have heterogeneous cerebellar hemisphere tumours, and this is thought to be related to the greater prevalence of desmoplastic tumours in adulthood. Few studies have addressed the MRI features of adult medulloblastoma and the specific characteristics of desmoplastic and classic tumours have not been analysed. Our aim was to analyse the imaging characteristics of desmoplastic (DM) and classic (CM) medulloblastomas in adult. We retrospectively studied preoperative MRI of six men and three women, median age 33 years, range 23-53 years, with pathologically proved medulloblastomas. There were six (67%) with DM. The tumour was in the cerebellar hemisphere in eight patients (89%), including the three with CM, one of which was bilateral. All tumours were heterogeneous, giving predominantly low or isointense signal on T1- and isointense signal on T2-weighted images. Cystic or necrotic areas in all patients were particularly visible on T2-weighted images. Contrast enhancement was absent in one DM and varied from slight to intense in eight (three CM), homogeneous in one DM and patchy in seven. All tumours extended to the surface of the cerebellum and two had well-defined margins. MRI does not allow a clear distinction between DM and CM in adults. (orig.)

  5. MRI Experiments for Introductory Physics

    Science.gov (United States)

    Taghizadeh, Sanaz; Lincoln, James

    2018-01-01

    The introductory physics classroom has long educated students about the properties of the atom and the nucleus. But absent from these lessons has been an informed discussion of magnetic resonance imaging (MRI) and its parent science nuclear magnetic resonance (NMR). Physics teachers should not miss the opportunity to instruct upon this highly…

  6. CT and MRI of the epigastrium - is the MRI competitive?

    International Nuclear Information System (INIS)

    Hamm, B. von

    1993-01-01

    The conclusion drawn in this article is: - CT will continue to rank first as a method for diagnostic evaluation of the entire abdomen. - MRI now offers advantages over CT for diagnostic identification of focal liver lesions, both with regard to detection as such and to a differential diagnosis of liver tumors. - CT continues to be the modality of first choice for diagnostic evaluation of acute pancreatitis. - CT offers advantages for the diagnostic evaluation of the gastrointestinal tract (as e.g. in case of complications in the course of inflammatory intestinal affection). - Interventional measures such as biopsies or abscess drainage will still be best controlled by CT, and MRI is not likely to become a really competitive method for such tasks in the foreseeable future. (orig.) [de

  7. MRI in subacute sclerosing panencephalitis

    International Nuclear Information System (INIS)

    Tuncay, R.; Akman-Demir, G.; Goekyigit, A.; Eraksoy, M.; Barlas, M.; Tolun, R.; Guersoy, G.

    1996-01-01

    Subacute sclerosing panencephalitis (SSPE) is a progressive, slow virus infection of the brain, caused by the measles virus, attacking children and young adults. We investigated 15 patients with SSPE by MRI, with 5 normal and 10 pathological results. In the early period, lesions were in the grey matter and subcortical white matter. They were asymmetrical and had a predilection for the posterior parts of the hemispheres. Later, high-signal changes in deep white matter and severe cerebral atrophy were observed. Parenchymal lesions significantly correlated with the duration of disease. A significant relationship between MRI findings and clinical stage was observed in the 1st year of the disease. (orig.). With 4 figs., 1 tab

  8. MRI of Wolfram syndrome (DIDMOAD)

    Energy Technology Data Exchange (ETDEWEB)

    Galluzzi, P.; Filosomi, G.; Vallone, I.M.; Venturi, C. [Dept. of Neuroradiology, Policlinico ' ' Le Scotte' ' , Siena (Italy); Bardelli, A.M. [Dept. of Ophthalmological Sciences, Unit of Paediatric Ophthalmology, University of Siena (Italy)

    1999-10-01

    Wolfram syndrome (DIDMOAD) is a rare diffuse neurodegenerative disorder characterised by diabetes insipidus, diabetes mellitus, optic atrophy, deafness, and a wide variety of abnormalities of the central nervous system, urinary tract and endocrine glands. It may be familial or sporadic. Reported features on MRI of the brain are absence of the physiological high signal of the posterior lobe of the pituitary, shrinkage of optic nerves, chiasm and tracts, atrophy of the hypothalamic region, brain stem, cerebellum, and cerebral cortex. We report a 12-year-old girl with a 5-year history without brain stem, cerebellar or cerebral atrophy. MRI showed an unusual feature: a focus of high signal on PD- and T2-weighted images in the right substantia nigra. This is consistent with previously reported neuropathological post-mortem studies, but has never been reported in vivo. (orig.)

  9. Partial volume effect in MRI

    International Nuclear Information System (INIS)

    Maeda, Munehiro; Yoshiya, Kazuhiko; Suzuki, Eiji

    1989-01-01

    According to the direction and the thickness of the imaging slice in tomography, the border between the tissues becomes unclear (partial volume effect). In the present MRI experiment, we examined border area between fat and water components using phantom in order to investigate the partial volume effect in MRI. In spin echo sequences, the intensity of the border area showed a linear relationship with composition of fat and water. Whereas, in inversion recovery and field echo sequences, we found the parameters to produce an extremely low intensity area at the border region between fat and water. This low intensity area was explained by cancellation of NMR signals from fat and water due to the difference in the direction of magnetic vectors. Clinically, partial volume effect can cause of mis-evaluation of walls, small nodules, tumor capsules and the tumor invasion in the use of inversion recovery and field echo sequences. (author)

  10. MRI in subacute sclerosing panencephalitis

    Energy Technology Data Exchange (ETDEWEB)

    Tuncay, R. [Department of Neurology, Istanbul Medical Faculty, University of Istanbul (Turkey); Akman-Demir, G. [Department of Neurology, Istanbul Medical Faculty, University of Istanbul (Turkey); Goekyigit, A. [Department of Neurology, Istanbul Medical Faculty, University of Istanbul (Turkey); Eraksoy, M. [Department of Neurology, Istanbul Medical Faculty, University of Istanbul (Turkey); Barlas, M. [Department of Neurology, Istanbul Medical Faculty, University of Istanbul (Turkey); Tolun, R. [Department of Neurology, Istanbul Medical Faculty, University of Istanbul (Turkey); Guersoy, G. [Department of Neurology, Istanbul Medical Faculty, University of Istanbul (Turkey)

    1996-10-01

    Subacute sclerosing panencephalitis (SSPE) is a progressive, slow virus infection of the brain, caused by the measles virus, attacking children and young adults. We investigated 15 patients with SSPE by MRI, with 5 normal and 10 pathological results. In the early period, lesions were in the grey matter and subcortical white matter. They were asymmetrical and had a predilection for the posterior parts of the hemispheres. Later, high-signal changes in deep white matter and severe cerebral atrophy were observed. Parenchymal lesions significantly correlated with the duration of disease. A significant relationship between MRI findings and clinical stage was observed in the 1st year of the disease. (orig.). With 4 figs., 1 tab.

  11. MRI in mucoviscidosis (cystic fibrosis)

    International Nuclear Information System (INIS)

    Eichinger, M.; Puderbach, M.; Kauczor, H.-U.; Heussel, C.-P.

    2006-01-01

    Cystic fibrosis (CF) is a multi-systemic disease with major impact on the lungs. Pulmonary manifestation is crucial for the prognosis and life expectancy of patients. Imaging modalities and lung function tests reflect the pulmonary status in these patients. The standard imaging modality for diagnosis and follow-up of pulmonary changes is chest x-ray. The gold standard for the detection of parenchymal lung changes remains high resolution computed tomography (HRCT), but this is not used routinely for CF-patients due to radiation exposure. Magnetic resonance imaging (MRI) used to be of no importance in monitoring cystic fibrosis lung disease, as shown in studies from the 1980s and early 1990s. The continuing improvement of MRI techniques, however, has allowed for an adequate application of this non-radiation method in diagnosing the major pulmonary findings in CF, in addition to the assessment of lung function. (orig.) [de

  12. MRI of Wolfram syndrome (DIDMOAD)

    International Nuclear Information System (INIS)

    Galluzzi, P.; Filosomi, G.; Vallone, I.M.; Venturi, C.; Bardelli, A.M.

    1999-01-01

    Wolfram syndrome (DIDMOAD) is a rare diffuse neurodegenerative disorder characterised by diabetes insipidus, diabetes mellitus, optic atrophy, deafness, and a wide variety of abnormalities of the central nervous system, urinary tract and endocrine glands. It may be familial or sporadic. Reported features on MRI of the brain are absence of the physiological high signal of the posterior lobe of the pituitary, shrinkage of optic nerves, chiasm and tracts, atrophy of the hypothalamic region, brain stem, cerebellum, and cerebral cortex. We report a 12-year-old girl with a 5-year history without brain stem, cerebellar or cerebral atrophy. MRI showed an unusual feature: a focus of high signal on PD- and T2-weighted images in the right substantia nigra. This is consistent with previously reported neuropathological post-mortem studies, but has never been reported in vivo. (orig.)

  13. MRI atlas of MS lesions

    Energy Technology Data Exchange (ETDEWEB)

    Sahraian, Mohammad Ali [Tehran Univ. of Medical Sciences Sina Hospital (Iran). Dept. of Neurology; Radue, Ernst-Wilhelm [Univ. Hospital Basel (Switzerland). Dept. of Neuroradiology

    2008-07-01

    MRI has become the main paraclinical test in the diagnosis and management of multiple sclerosis. We have demonstrated more than 400 pictures of different typical and atypical MS lesions in this atlas. Each image has a teaching point. New diagnostic criteria and differential diagnosis are discussed and the book is supported by a teaching DVD where the reader can see MS lesions in different slices and sequences. (orig.)

  14. Multicentre structural and functional MRI

    OpenAIRE

    Gountouna, Viktoria-Eleni

    2014-01-01

    Neuroimaging techniques are likely to continue to improve our understanding of the brain in health and disease, but studies tend to be small, based in one imaging centre and of uncertain generalisability. Multicentre imaging studies therefore have great appeal but it is not yet clear under which circumstances data from different scanners can be combined. The successful harmonisation of multiple Magnetic Resonance Imaging (MRI) machines will increase study power, flexibility and...

  15. MRI-induced retrocalcaneal bursitis

    International Nuclear Information System (INIS)

    Tol, J.L.; Dijk, C.N. van; Maas, M.

    1999-01-01

    This case report describes a patient with acute retrocalcaneal bursitis, which developed after MRI examination of the ankle. The sagittal T2*-weighted gradient echo sequence revealed an extensive susceptibility artifact in the area surrounding the Achilles tendon near its insertion at the os calcis. This artifact was caused by postsurgical metallic particles. We postulate that these particles were mechanically stimulated by the magnetic field and induced the inflammatory response. (orig.)

  16. MRI-induced retrocalcaneal bursitis

    Energy Technology Data Exchange (ETDEWEB)

    Tol, J.L.; Dijk, C.N. van [Dept. of Orthopaedic Surgery, University of Amsterdam (Netherlands); Maas, M. [Dept. of Radiology, University of Amsterdam (Netherlands)

    1999-10-01

    This case report describes a patient with acute retrocalcaneal bursitis, which developed after MRI examination of the ankle. The sagittal T2*-weighted gradient echo sequence revealed an extensive susceptibility artifact in the area surrounding the Achilles tendon near its insertion at the os calcis. This artifact was caused by postsurgical metallic particles. We postulate that these particles were mechanically stimulated by the magnetic field and induced the inflammatory response. (orig.)

  17. MRI and hydrocephalus in childhood

    International Nuclear Information System (INIS)

    Britton, J.; Marsh, H.; Kendall, B.; Kingsley, D.

    1988-01-01

    In six young patients presenting with raised intracranial pressure during the period of a year, CT revealed the presence of hydrocephalus, but not the cause. Magnetic Resonance Imaging not only showed the site and nature of the obstructing lesion, but also detected additional clinically silent spinal cord tumors in five of the patients. The place of MRI in the diagnosis of diseases involving the region of the cranio-cervical junction and in the elucidation of 'unexplained hydrocephalus' is considered. (orig.)

  18. MRI of vulvar Crohn disease

    Energy Technology Data Exchange (ETDEWEB)

    Pai, Deepa; Dillman, Jonathan R.; Mahani, Maryam Ghadimi; Strouse, Peter J. [University of Michigan Health System, Department of Radiology, Section of Pediatric Radiology, C.S. Mott Children' s Hospital, F3503, Ann Arbor, MI (United States); Adler, Jeremy [University of Michigan Health System, Department of Pediatrics and Communicable Diseases, Division of Pediatric Gastroenterology, C. S. Mott Children' s Hospital, Ann Arbor, MI (United States)

    2011-04-15

    Crohn disease is a chronic granulomatous inflammatory disorder that most commonly affects the gastrointestinal tract, particularly the distal small bowel and colon. While certain extraintestinal manifestations of Crohn disease are relatively common and well-known, others, such as metastatic cutaneous involvement, are quite rare and may be difficult to recognize, particularly in the pediatric population. This case report illustrates the magnetic resonance imaging (MRI) appearance of vulvar region cutaneous Crohn disease in an 11-year-old girl. (orig.)

  19. Mandarin functional MRI Language paradigms

    OpenAIRE

    Ci, He; van Graan, Andre; Gonz?lvez, Gloria; Thompson, Pamela; Hill, Andrea; Duncan, John S.

    2016-01-01

    Abstract Objective The objective of this study was to implement convenient, fast, and accurate Mandarin task paradigms for functional MRI, and to locate the Chinese language functional areas in frontal and temporal lobes. Materials and Methods Nineteen healthy Chinese volunteers participated in this study, which utilized a block design with four language tasks: auditory naming (AN), picture naming (PN), verbal fluency?character (VFC), and verbal fluency?letter (VFL). All functional images wer...

  20. MRI EVALUATION OF TRIGEMINAL NEURALGIA

    Directory of Open Access Journals (Sweden)

    Sama Surya Sravani

    2017-04-01

    Full Text Available BACKGROUND Neuralgia is the set of symptoms associated with nerve dysfunction. The most common of these symptoms is pain, which can occur intermittently in one area of the body or can radiate along the length of a damaged nerve. The most common type of neuralgia is trigeminal neuralgia. This study focuses on the effectiveness of MRI in visualising the entire course of trigeminal nerve and to diagnose the exact location, aetiology responsible for trigeminal neuralgia and possible pretreatment evaluation. MATERIALS AND METHODS Clinical records and imaging studies of 30 patients between the ages of 18-60 years who presented to the Department of Radiodiagnosis, KIMS, for brain magnetic resonance imaging with (Philips 1.5T machine during June 2015 to December 2016 were analysed retrospectively. RESULTS  The entire course of trigeminal nerve is evaluated in these patients.  There are different causes of trigeminal neuralgia, but in our study, most frequent cause is mechanical irritation of nerve is due to neurovascular contact (24 cases. The other causes identified are cerebellopontine angle lesions, brainstem tumours, demyelinating disease involving brainstem.  The cisternal portion of the nerve is the most common site of involvement. CONCLUSION Trigeminal nerve is the largest cranial nerve. MRI is unique as it produces images of entire course of the nerve. Of the many causes of trigeminal neuralgia, neurovascular conflict is the most common cause. The exact location and degree of neurovascular compression is graded on MRI.

  1. MRI characteristics of midbrain tumours

    International Nuclear Information System (INIS)

    Sun, B.; Wang, C.C.; Wang, J.

    1999-01-01

    We diagnosed 60 cases of midbrain tumours by MRI between 1993 to 1997. There were 39 males and 21 females, aged 2-64 years, mean 25.6 years. We found 38 patients with true intramedullary midbrain tumours, 11 predominantly in the tectum, 20 in the tegmentum and 7 with a downward extension to the pons; there were 7 within the cerebral aqueduct. There were 22 patients with infiltrating midbrain tumours extending from adjacent structures, 11 cases each from the thalamus and pineal region. All patients received surgical treatment. Gross total resection was achieved in 42 cases, subtotal (> 75 %) resection in 18. Pathological diagnoses included 16 low-grade and 15 high-grade astrocytomas; 5 oligodendroastrocytomas; 2 ependymomas; 11 glioblastomas; and 11 pineal parenchymal or germ-cell tumours. Midbrain tumours are a heterogeneous group of neoplasms, with wide variation in clinical and MRI features, related to the site and type of tumour. MRI not only allows precise analysis of their growth pattern, but also can lead to a correct preoperative diagnosis in the majority of cases. (orig.) (orig.)

  2. MRI findings of extramedullary haemopoiesis

    International Nuclear Information System (INIS)

    Chourmouzi, D.; Pistevou-Gompaki, K.; Plataniotis, G.; Skaragas, G.; Papadopoulos, L.; Drevelegas, A.

    2001-01-01

    Extramedullary haemopoiesis (EH) is a compensatory process associated with chronic haemolytic anaemia. It is rare, however, for such an abnormality to cause spinal cord compression. We present two patients with known beta-thalassaemia intermedia who developed spinal cord compression due to masses of extramedullary haematopoietic tissue in the epidural space of the thoracic spine. The EH masses were diagnosed by MRI as an isointense epidural lesion on both T1- and T2-weighted images, compressing severely the spinal cord. After administration of a paramagnetic agent, an intermediate enhancement of the masses was evident. All the vertebral bodies had low to intermediate signal intensity as a result of displacement of fatty marrow by haematopoietic marrow. Expansion of thoracic ribs with bilateral paravertebral masses were characteristic. A small dose of radiotherapy was given and marked improvement in neurological symptoms was evident. An MRI examination established shrinkage of the mass and decompression of spinal cord. The role of MRI in diagnosis of EH masses is essential and radiation therapy is a very effective treatment for this rare complication. (orig.)

  3. MRI of discoid lateral meniscus

    International Nuclear Information System (INIS)

    Araki, Yutaka; Ootani, Masatoshi; Furukawa, Tomoaki; Yamamoto, Tadatsuka; Tomoda, Kaname; Tsukaguchi, Isao; Mitomo, Masanori.

    1991-01-01

    We retrospectively reviewed the MR examinations of 10 patients (17 knees) with surgically documented discoid lateral meniscus of the knee joint. As MRI of the knee is being used more often, the criteria for diagnosis of this entity with MRI need to be established. We tried to define MRI criteria for the detection of discoid menisci by performing numerical measurements of MR images on a display screen. The transverse diameter of the midbody of a discoid lateral meniscus averaged 21.9 mm (normal control: 8.6 mm), and its proportion to the transverse width of the tibia averaged 29.4% (normal control: 12.0%). The measurable difference in height between the discoid and the medial meniscus was negligible. The number of sagittal sections on which the anterior and posterior horns connected varied from two to five in cases of discoid lateral meniscus, and from zero to two in normal controls. Among these parameters, the transverse diameter and its proportion of the transverse width of the tibia proved to be the most reliable. We concluded that a discoid meniscus is indicated if a transverse diameter of a lateral meniscus exceeds 15 mm (proportion to the tibia: 20%). (author)

  4. MRI findings of juvenile psoriatic arthritis

    International Nuclear Information System (INIS)

    Lee, Edward Y.; Kleinman, Paul K.; Sundel, Robert P.; Kim, Susan; Zurakowski, David

    2008-01-01

    The aim of this study was to describe the magnetic resonance imaging (MRI) features of juvenile psoriatic arthritis (JpsA) in children in order to facilitate early diagnosis and proper management. Two pediatric radiologists retrospectively reviewed in consensus a total of 37 abnormal MRI examinations from 31 pediatric patients (nine boys, 22 girls; age range 1-17 years; mean age 9.4 years) who had a definite diagnosis of JpsA and underwent MRI. Each MRI was evaluated for synovium abnormality (thickening and enhancement), joint effusion (small, moderate, and large), bone marrow abnormality (edema, enhancement, and location of abnormality), soft tissue abnormality (edema, enhancement, atrophy, and fatty infiltration), tendon abnormality (thickening, edema, tendon sheath fluid, and enhancement), and articular abnormality (joint space narrowing and erosion). The distribution of abnormal MRI findings among the six categories for the 37 MRI examinations was evaluated. The number of abnormal MRI findings for each MRI examination was assessed. Age at MRI examination and all six categories of abnormal MRI findings according to gender were evaluated. There were a total 96 abnormal MRI findings noted on 37 abnormal MRI examinations from 31 pediatric patients. The 37 abnormal MRI examinations included MRI of the hand (n=8), knee (n = 8), ankle (n = 5), pelvis (n = 5), temporomandibular joint (n = 4), wrist (n = 3), foot (n = 2), elbow (n = 1), and shoulder (n = 1). Twenty-eight diffuse synovial thickening and/or enhancement were the most common MRI abnormality (29.2%). Joint effusion comprised 22 abnormal MRI findings (22.9%). There were 16 abnormal MRI bone marrow edema and/or enhancement findings (16.7%), and in seven (7.3%) the edema involved non-articular sites. Soft tissue abnormality manifested as edema and/or enhancement constituted 14 abnormal MRI findings (14.5%). There were ten MRI abnormalities (10.4%) involving tendons. Articular abnormality seen as joint space

  5. MRI findings of juvenile psoriatic arthritis

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Edward Y.; Kleinman, Paul K. [Harvard Medical School, Department of Radiology, Boston, MA (United States); Children' s Hospital Boston, MA (United States); Sundel, Robert P.; Kim, Susan [Harvard Medical School, Rheumatology Program, Division of Immunology and the Department of Pediatrics, Boston, MA (United States); Children' s Hospital Boston, MA (United States); Zurakowski, David [Harvard Medical School, Department of Radiology, Boston, MA (United States); Harvard Medical School, Department of Orthopaedic Surgery, Boston, MA (United States); Children' s Hospital Boston, MA (United States)

    2008-11-15

    The aim of this study was to describe the magnetic resonance imaging (MRI) features of juvenile psoriatic arthritis (JpsA) in children in order to facilitate early diagnosis and proper management. Two pediatric radiologists retrospectively reviewed in consensus a total of 37 abnormal MRI examinations from 31 pediatric patients (nine boys, 22 girls; age range 1-17 years; mean age 9.4 years) who had a definite diagnosis of JpsA and underwent MRI. Each MRI was evaluated for synovium abnormality (thickening and enhancement), joint effusion (small, moderate, and large), bone marrow abnormality (edema, enhancement, and location of abnormality), soft tissue abnormality (edema, enhancement, atrophy, and fatty infiltration), tendon abnormality (thickening, edema, tendon sheath fluid, and enhancement), and articular abnormality (joint space narrowing and erosion). The distribution of abnormal MRI findings among the six categories for the 37 MRI examinations was evaluated. The number of abnormal MRI findings for each MRI examination was assessed. Age at MRI examination and all six categories of abnormal MRI findings according to gender were evaluated. There were a total 96 abnormal MRI findings noted on 37 abnormal MRI examinations from 31 pediatric patients. The 37 abnormal MRI examinations included MRI of the hand (n=8), knee (n = 8), ankle (n = 5), pelvis (n = 5), temporomandibular joint (n = 4), wrist (n = 3), foot (n = 2), elbow (n = 1), and shoulder (n = 1). Twenty-eight diffuse synovial thickening and/or enhancement were the most common MRI abnormality (29.2%). Joint effusion comprised 22 abnormal MRI findings (22.9%). There were 16 abnormal MRI bone marrow edema and/or enhancement findings (16.7%), and in seven (7.3%) the edema involved non-articular sites. Soft tissue abnormality manifested as edema and/or enhancement constituted 14 abnormal MRI findings (14.5%). There were ten MRI abnormalities (10.4%) involving tendons. Articular abnormality seen as joint space

  6. An MRI-Conditional External Cardiac Defibrillator for Resuscitation Within the MRI Scanner Bore

    Science.gov (United States)

    Schmidt, Ehud J.; Watkins, Ronald D.; Zviman, Menekhem M.; Guttman, Michael A.; Wang, Wei; Halperin, Henry A.

    2016-01-01

    Background Subjects undergoing cardiac arrest within an MRI scanner are currently removed from the bore and then from the MRI suite, prior to delivery of CPR and defibrillation, potentially increasing risk of mortality. This precludes many higher-risk (acute-ischemic, acute-stroke) patients from undergoing MRI imaging and MRI-guided intervention. An MRI-conditional cardiac defibrillator should enable scanning with defibrillation pads attached and the generator ON, enabling application of defibrillation within the MRI seconds after a cardiac event. An MRI-conditional external defibrillator may improve patient acceptance for MRI procedures. Methods and Results A commercial external defibrillator was rendered 1.5 Tesla MRI-conditional by addition of novel Radio-Frequency (RF) filters between the generator and commercial disposable surface-pads. The RF filters reduced emission into the MRI scanner, and prevented cable/surface-pad heating during imaging, while preserving all the defibrillator’s monitoring and delivery functions. Human volunteers were imaged using high Specific-Absorption-Rate sequences to validate MRI image quality (IQ) and lack of heating. Swine were electrically fibrillated (N=4) and thereafter defibrillated both outside and inside the MRI bore. MRI IQ was reduced by 0.8 or 1.6 dB, with the generator in monitoring mode and operating on battery or AC power, respectively. Commercial surface-pads did not create artifacts deeper than 6mm below the skin surface. RF heating was within FDA guidelines. Defibrillation was completely successful inside and outside the MRI bore. Conclusions A prototype MRI-conditional defibrillation system successfully defibrillated in the MRI without degrading image quality, or increasing the time needed for defibrillation. It can increase patient acceptance for MRI procedures. PMID:27729363

  7. Uterus MRI. Normal and pathological aspects

    International Nuclear Information System (INIS)

    Moulin, G.; Bartoli, J.M.; Gaubert, J.Y.; Bayle, O.; Distefano-Louineau, D.; Kasbarian, M.

    1991-01-01

    Magnetic Resonance Imaging (MRI), a non invasive procedure, is taking a place of growing importance as a means of radiological exploration. Its use in uterine pathologies has shown considerable developments. This requires an excellent knowledge of the normal and pathological aspects of the uterus. In fact it exists a zonal anatomy of the uterus which varies according to hormonal impregnation and this is very well seen by MRI. MRI gives excellent results in the diagnosis and study of different uterine pathologies. The radiological appearance of leiomyomas differs depending on the presence or not of degenerative changes within them. Uterine adenomyosis is also well studied by MRI. Lastly different studies in the literature have shown MRI to be a reliable method of exploration with a high degree of fiability, specificity and sensibility to study the local spread of malignant uterine diseases. The authors report their experience and also that present in the literature concerning the study of the uterus by MRI [fr

  8. Designing a compact MRI motion phantom

    Directory of Open Access Journals (Sweden)

    Schmiedel Max

    2016-09-01

    Full Text Available Even today, dealing with motion artifacts in magnetic resonance imaging (MRI is a challenging task. Image corruption due to spontaneous body motion complicates diagnosis. In this work, an MRI phantom for rigid motion is presented. It is used to generate motion-corrupted data, which can serve for evaluation of blind motion compensation algorithms. In contrast to commercially available MRI motion phantoms, the presented setup works on small animal MRI systems. Furthermore, retrospective gating is performed on the data, which can be used as a reference for novel motion compensation approaches. The motion of the signal source can be reconstructed using motor trigger signals and be utilized as the ground truth for motion estimation. The proposed setup results in motion corrected images. Moreover, the importance of preprocessing the MRI raw data, e.g. phase-drift correction, is demonstrated. The gained knowledge can be used to design an MRI phantom for elastic motion.

  9. PH-Responsive mechanised nanoparticles gated by semirotaxanes

    KAUST Repository

    Khashab, Niveen M.; Belowich, Matthew E.; Trabolsi, Ali; Friedman, Douglas C.; Valente, Cory; Lau, Yuen; Khatib, Hussam A.; Zink, Jeffrey I.; Stoddart, Fraser Fraser Raser

    2009-01-01

    A [2]pseudorotaxane-based mechanised nanoparticle system, which operates within an aqueous acidic environment, has been prepared and characterised; this integrated system affords both water-soluble stalk and ring components in an effort to improve the biocompatibility of these promising new drug delivery vehicles. © The Royal Society of Chemistry 2009.

  10. pH Responsiveness of hydrogels formed by telechelic polyampholytes

    Czech Academy of Sciences Publication Activity Database

    Dyakonova, M. A.; Gotzamanis, G.; Niebuur, B.-J.; Vishnevetskaya, N. S.; Raftopoulos, K. N.; Di, Z.; Filippov, Sergey K.; Tsitsilianis, C.; Papadakis, C. M.

    2017-01-01

    Roč. 13, č. 19 (2017), s. 3568-3579 ISSN 1744-683X R&D Projects: GA ČR(CZ) GC15-10527J Institutional support: RVO:61389013 Keywords : polyampholyte * self-assembly * block copolymers Subject RIV: CF - Physical ; Theoretical Chemistry OBOR OECD: Physical chemistry Impact factor: 3.889, year: 2016

  11. Engineering a pH responsive pore forming protein.

    Science.gov (United States)

    Kisovec, Matic; Rezelj, Saša; Knap, Primož; Cajnko, Miša Mojca; Caserman, Simon; Flašker, Ajda; Žnidaršič, Nada; Repič, Matej; Mavri, Janez; Ruan, Yi; Scheuring, Simon; Podobnik, Marjetka; Anderluh, Gregor

    2017-02-08

    Listeriolysin O (LLO) is a cytolysin capable of forming pores in cholesterol-rich lipid membranes of host cells. It is conveniently suited for engineering a pH-governed responsiveness, due to a pH sensor identified in its structure that was shown before to affect its stability. Here we introduced a new level of control of its hemolytic activity by making a variant with hemolytic activity that was pH-dependent. Based on detailed structural analysis coupled with molecular dynamics and mutational analysis, we found that the bulky side chain of Tyr406 allosterically affects the pH sensor. Molecular dynamics simulation further suggested which other amino acid residues may also allosterically influence the pH-sensor. LLO was engineered to the point where it can, in a pH-regulated manner, perforate artificial and cellular membranes. The single mutant Tyr406Ala bound to membranes and oligomerized similarly to the wild-type LLO, however, the final membrane insertion step was pH-affected by the introduced mutation. We show that the mutant toxin can be activated at the surface of artificial membranes or living cells by a single wash with slightly acidic pH buffer. Y406A mutant has a high potential in development of novel nanobiotechnological applications such as controlled release of substances or as a sensor of environmental pH.

  12. Engineering a pH responsive pore forming protein

    Science.gov (United States)

    Kisovec, Matic; Rezelj, Saša; Knap, Primož; Cajnko, Miša Mojca; Caserman, Simon; Flašker, Ajda; Žnidaršič, Nada; Repič, Matej; Mavri, Janez; Ruan, Yi; Scheuring, Simon; Podobnik, Marjetka; Anderluh, Gregor

    2017-02-01

    Listeriolysin O (LLO) is a cytolysin capable of forming pores in cholesterol-rich lipid membranes of host cells. It is conveniently suited for engineering a pH-governed responsiveness, due to a pH sensor identified in its structure that was shown before to affect its stability. Here we introduced a new level of control of its hemolytic activity by making a variant with hemolytic activity that was pH-dependent. Based on detailed structural analysis coupled with molecular dynamics and mutational analysis, we found that the bulky side chain of Tyr406 allosterically affects the pH sensor. Molecular dynamics simulation further suggested which other amino acid residues may also allosterically influence the pH-sensor. LLO was engineered to the point where it can, in a pH-regulated manner, perforate artificial and cellular membranes. The single mutant Tyr406Ala bound to membranes and oligomerized similarly to the wild-type LLO, however, the final membrane insertion step was pH-affected by the introduced mutation. We show that the mutant toxin can be activated at the surface of artificial membranes or living cells by a single wash with slightly acidic pH buffer. Y406A mutant has a high potential in development of novel nanobiotechnological applications such as controlled release of substances or as a sensor of environmental pH.

  13. Type gaucher disease: radiographic and MRI manifestations

    International Nuclear Information System (INIS)

    Dong Yanqing; Li Kuncheng; Wang Yunzhao; Tian Ding

    1999-01-01

    Objective: To enhance the understanding of Gaucher disease (GD) type I bone involvement on imaging findings. Methods: The X-ray plain film and MRI findings of GD type I were reported, and literature reviewed. Results: The X-ray plain film of GD had characteristic change. The extent of bone involvement demonstrated could be depicted in longitudinal direction and the changes of marrow involvement on MRI. Conclusions: MRI is the best way to diagnose the bone involvement of GD

  14. MRI of Adnexal Masses in Pregnancy

    Science.gov (United States)

    Telischak, Nicholas A.; Yeh, Benjamin M.; Joe, Bonnie N.; Westphalen, Antonio C.; Poder, Liina; Coakley, Fergus V.

    2009-01-01

    OBJECTIVE The objective of this article is to provide a practical review of the incremental benefit of MRI in the assessment of adnexal masses in pregnancy. CONCLUSION MRI can assist sonographic assessment of adnexal masses in pregnancy by depicting the characteristic findings of exophytic leiomyoma, red degeneration of leiomyoma, endometrioma, decidualized endometrioma, and massive ovarian edema. Accordingly, MRI should be considered as a useful adjunct when sonography is inconclusive or insufficient to guide management of adnexal masses discovered in pregnancy. PMID:18647903

  15. Incidental findings on MRI of the spine

    Energy Technology Data Exchange (ETDEWEB)

    Kamath, S.; Jain, N.; Goyal, N.; Mansour, R. [Department of Radiology, University Hospital of Wales, Cardiff (United Kingdom); Mukherjee, K. [Department of Radiology, University Hospital of Wales, Cardiff (United Kingdom)], E-mail: kausikmukherjee@doctors.org.uk

    2009-04-15

    MRI is widely used as the imaging of choice for spinal disorders and may reveal either a clinically insignificant incidental abnormality or a significant lesion, unrelated to the spine, which may explain the patient's symptoms. This article attempts to establish the importance of such findings and describes a sensible approach to the reporting of MRI examinations of the spine with special attention to the incidental findings commonly encountered. The MRI characteristics of such findings are briefly described.

  16. Competitive advantage of PET/MRI

    Energy Technology Data Exchange (ETDEWEB)

    Jadvar, Hossein, E-mail: jadvar@usc.edu; Colletti, Patrick M.

    2014-01-15

    Multimodality imaging has made great strides in the imaging evaluation of patients with a variety of diseases. Positron emission tomography/computed tomography (PET/CT) is now established as the imaging modality of choice in many clinical conditions, particularly in oncology. While the initial development of combined PET/magnetic resonance imaging (PET/MRI) was in the preclinical arena, hybrid PET/MR scanners are now available for clinical use. PET/MRI combines the unique features of MRI including excellent soft tissue contrast, diffusion-weighted imaging, dynamic contrast-enhanced imaging, fMRI and other specialized sequences as well as MR spectroscopy with the quantitative physiologic information that is provided by PET. Most evidence for the potential clinical utility of PET/MRI is based on studies performed with side-by-side comparison or software-fused MRI and PET images. Data on distinctive utility of hybrid PET/MRI are rapidly emerging. There are potential competitive advantages of PET/MRI over PET/CT. In general, PET/MRI may be preferred over PET/CT where the unique features of MRI provide more robust imaging evaluation in certain clinical settings. The exact role and potential utility of simultaneous data acquisition in specific research and clinical settings will need to be defined. It may be that simultaneous PET/MRI will be best suited for clinical situations that are disease-specific, organ-specific, related to diseases of the children or in those patients undergoing repeated imaging for whom cumulative radiation dose must be kept as low as reasonably achievable. PET/MRI also offers interesting opportunities for use of dual modality probes. Upon clear definition of clinical utility, other important and practical issues related to business operational model, clinical workflow and reimbursement will also be resolved.

  17. Competitive advantage of PET/MRI.

    Science.gov (United States)

    Jadvar, Hossein; Colletti, Patrick M

    2014-01-01

    Multimodality imaging has made great strides in the imaging evaluation of patients with a variety of diseases. Positron emission tomography/computed tomography (PET/CT) is now established as the imaging modality of choice in many clinical conditions, particularly in oncology. While the initial development of combined PET/magnetic resonance imaging (PET/MRI) was in the preclinical arena, hybrid PET/MR scanners are now available for clinical use. PET/MRI combines the unique features of MRI including excellent soft tissue contrast, diffusion-weighted imaging, dynamic contrast-enhanced imaging, fMRI and other specialized sequences as well as MR spectroscopy with the quantitative physiologic information that is provided by PET. Most evidence for the potential clinical utility of PET/MRI is based on studies performed with side-by-side comparison or software-fused MRI and PET images. Data on distinctive utility of hybrid PET/MRI are rapidly emerging. There are potential competitive advantages of PET/MRI over PET/CT. In general, PET/MRI may be preferred over PET/CT where the unique features of MRI provide more robust imaging evaluation in certain clinical settings. The exact role and potential utility of simultaneous data acquisition in specific research and clinical settings will need to be defined. It may be that simultaneous PET/MRI will be best suited for clinical situations that are disease-specific, organ-specific, related to diseases of the children or in those patients undergoing repeated imaging for whom cumulative radiation dose must be kept as low as reasonably achievable. PET/MRI also offers interesting opportunities for use of dual modality probes. Upon clear definition of clinical utility, other important and practical issues related to business operational model, clinical workflow and reimbursement will also be resolved. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  18. Competitive advantage of PET/MRI

    International Nuclear Information System (INIS)

    Jadvar, Hossein; Colletti, Patrick M.

    2014-01-01

    Multimodality imaging has made great strides in the imaging evaluation of patients with a variety of diseases. Positron emission tomography/computed tomography (PET/CT) is now established as the imaging modality of choice in many clinical conditions, particularly in oncology. While the initial development of combined PET/magnetic resonance imaging (PET/MRI) was in the preclinical arena, hybrid PET/MR scanners are now available for clinical use. PET/MRI combines the unique features of MRI including excellent soft tissue contrast, diffusion-weighted imaging, dynamic contrast-enhanced imaging, fMRI and other specialized sequences as well as MR spectroscopy with the quantitative physiologic information that is provided by PET. Most evidence for the potential clinical utility of PET/MRI is based on studies performed with side-by-side comparison or software-fused MRI and PET images. Data on distinctive utility of hybrid PET/MRI are rapidly emerging. There are potential competitive advantages of PET/MRI over PET/CT. In general, PET/MRI may be preferred over PET/CT where the unique features of MRI provide more robust imaging evaluation in certain clinical settings. The exact role and potential utility of simultaneous data acquisition in specific research and clinical settings will need to be defined. It may be that simultaneous PET/MRI will be best suited for clinical situations that are disease-specific, organ-specific, related to diseases of the children or in those patients undergoing repeated imaging for whom cumulative radiation dose must be kept as low as reasonably achievable. PET/MRI also offers interesting opportunities for use of dual modality probes. Upon clear definition of clinical utility, other important and practical issues related to business operational model, clinical workflow and reimbursement will also be resolved

  19. PET/MRI. Challenges, solutions and perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Herzog, Hans [Forschungszentrum Juelich (Germany). Inst. of Neuroscience and Medicine - 4

    2012-07-01

    Already from the start of PET/CT integrating positron emission tomography (PET) and computed tomography (CT) in one instrument, there have been considerations how to combine PET and magnetic resonance imaging (MRI) so that their complementary abilities can be utilized in a single investigation. Since classical PET electronics fail in an even weak magnetic field and PET signal processing might disturb high-frequency signals of MRI, it soon became clear that new solutions had to be found to avoid mutual interferences. During the last fifteen years a number of different approaches towards PET/MRI for small animal imaging have been developed by research groups which together with their specific features are summarized in this review. Recently, PET/MRI for human imaging became available as well - this time by industrial initiatives. First some prototypes of BrainPET/MRI were developed followed by commercial products for simultaneous and non-simultaneous whole-body PET/MRI. Although only PET/MRI integrated in one scanner offers the full diversity of complementary multiparametric imaging, there are also promising applications of non-simultaneous sequential PET/MRI. While describing the present instrumentation for human PET/MRI, this review discusses the challenges and promises related to this new imaging technology. (orig.)

  20. Research progress of functional MRI in depression

    International Nuclear Information System (INIS)

    Xie Shenghui; Niu Guangming; Han Xiaodong; Qiao Pengfei

    2013-01-01

    The mood disorders of depression are associated with abnormalities of brain structure and function, and exploring their pathological mechanism has important significance for the choice of treatment and the curative effect evaluation. In recent years, the research of MRI on brain structure and function of depression has made great progress, especially in functional magnetic resonance imaging (fMRI). fMRI can detect the functional change in real time, and also can display the activity of brain and changes in the nerve pathways in patients with depression. This article summarizes the present research situation and progress of MRI in the diagnosis of depression. (authors)