WorldWideScience

Sample records for clinical magnetic resonance

  1. Clinical magnetic resonance: imaging and spectroscopy

    International Nuclear Information System (INIS)

    Andrew, E.R.; Bydder, Graeme; Griffiths, John; Iles, Richard; Styles, Peter

    1990-01-01

    This book begins with a readable, comprehensive but non-mathematical introduction to the basic underlying principles of magnetic resonance. Further chapters include information on the theory and principles of MRI and MRS, the interpretation of MR images, the clinical applications and scope of MRI and MRS, practical aspects of spectroscopy and magnetic resonance, and also the practical problems associated with the siting, safety and operation of large MRI and MRS equipment. (author)

  2. Cardiac magnetic resonance imaging in clinical practice

    Directory of Open Access Journals (Sweden)

    Adriana Dias Barranhas

    2014-01-01

    Full Text Available Objective To evaluate and describe indications, mainly diagnoses and cardiac magnetic resonance imaging findings observed in clinical practice. Materials and Methods Retrospective and descriptive study of cardiac magnetic resonance performed at a private hospital and clinic in the city of Niterói, RJ, Brazil, in the period from May 2007 to April 2011. Results The sample included a total of 1000 studies performed in patients with a mean age of 53.7 ± 16.2 years and predominance for male gender (57.2%. The majority of indications were related to assessment of myocardial perfusion at rest and under pharmacological stress (507/1000; 51%, with positive results in 36.2% of them. Suspected myocarditis was the second most frequent indication (140/1000; 14%, with positive results in 63.4% of cases. These two indications were followed by study of arrhythmias (116/1000; 12%, myocardial viability (69/1000; 7% and evaluation of cardiomyopathies (47/1000; 5%. In a subanalysis, it was possible to identify that most patients were assessed on an outpatient basis (58.42%. Conclusion Cardiac magnetic resonance has been routinely performed in clinical practice, either on an outpatient or emergency/inpatient basis, and myocardial ischemia represented the main indication, followed by investigation of myocarditis, arrhythmogenic right ventricular dysplasia and myocardial viability.

  3. Clinical applications of cardiovascular magnetic resonance imaging

    International Nuclear Information System (INIS)

    Marcu, C.B.; Beek, A.M.; Van Rossum, A.C.

    2006-01-01

    Cardiovascular magnetic resonance imaging (MRI) has evolved from an effective research tool into a clinically proven, safe and comprehensive imaging modality. It provides anatomic and functional information in acquired and congenital heart disease and is the most precise technique for quantification of ventricular volumes, function and mass. Owing to its excellent interstudy reproducibility, cardiovascular MRI is the optimal method for assessment of changes in ventricular parameters after therapeutic intervention. Delayed contrast enhancement is an accurate and robust method used in the diagnosis of ischemic and nonischemic cardiomyopathies and less common diseases, such as cardiac sarcoidosis and myocarditis. First-pass magnetic contrast myocardial perfusion is becoming an alternative to radionuclide techniques for the detection of coronary atherosclerotic disease. In this review we outline the techniques used in cardiovascular MRI and discuss the most common clinical applications. (author)

  4. Clinical application of magnetic resonance coronary angiography

    International Nuclear Information System (INIS)

    Murakami, Akihiko; Onoe, Teruyuki; Kodera, Akifumi; Ohtsuki, Tetsuya; Shiomi, Akio; Ida, Masaaki; Sawada, Takahisa

    1999-01-01

    We performed the magnetic resonance coronary angiography (MRCA) in the cases which underwent coronary angiography (CAG) and obtained images were compared. Lesion with significant constriction more than 75% on CAG were determined as abnormal findings on MRCA, however, lesions with about 50% constriction were as the normal findings. On the assessment of the re-constriction after PTCA, the changes in signal were found in about half of cases. This may come from the contribution of flexion lesions, the difficulty to assess moderate constriction after PTCA, etc. For the anomalous aortic origin of coronary artery, peripheral large vessels could be simultaneously imaged by MRCA and be also assessed among their clear spatial relationship. Although MRCA has some problems on the assessment for flexion or moderate constriction, these results suggested that MRCA is useful to clinical application as the non-invasive examination. (K.H.)

  5. Magnetic resonance imaging in clinically-definite multiple sclerosis

    International Nuclear Information System (INIS)

    Noakes, J.B.; Herkes, G.K.; Frith, J.A.

    1990-01-01

    Forty-two patients with clinically-definite multiple sclerosis were examined by magnetic resonance imaging using a 1.5-T instrument. Magnetic resonance imaging detected an abnormality in 90% of patients. In four patients, no lesions were demonstrated. The number, size and site of the lesions by magnetic resonance imaging were compared with the patients' clinical status and other variables. The Kurtzke disability status scale score increased in patients with corpus callosum atrophy, brainstem and basal ganglia lesions, and correlated with the total number of lesions. No correlation was shown between the findings of magnetic resonance imaging and disease duration, age, sex or pattern-reversal visual-evoked potentials. The variety of magnetic resonance images that could be obtained in patients with clinically-definite multiple sclerosis is highlighted. 24 refs., 8 figs., 1 tab

  6. Magnetic Resonance Imaging in Malawi: Contributions to Clinical ...

    African Journals Online (AJOL)

    Magnetic Resonance Imaging in Malawi: Contributions to Clinical Care, Medical Education and Biomedical Research. MJ Potchen, S Kampondeni, GL Birbeck, CA Hammond, A Gonani, KS Phiri, KB Seydel, TE Taylor ...

  7. Magnetic resonance imaging for clinical management of rectal cancer

    DEFF Research Database (Denmark)

    Beets-Tan, Regina G H; Lambregts, Doenja M J; Maas, Monique

    2018-01-01

    OBJECTIVES: To update the 2012 ESGAR consensus guidelines on the acquisition, interpretation and reporting of magnetic resonance imaging (MRI) for clinical staging and restaging of rectal cancer. METHODS: Fourteen abdominal imaging experts from the European Society of Gastrointestinal and Abdomin...

  8. Magnetic resonance spectroscopy: clinical application in neuroradiology

    International Nuclear Information System (INIS)

    Penev, L.

    2012-01-01

    Full text: Magnetic Resonance Spectroscopy (MRS) provides a non-invasive method of studying metabolism in vivo. Magnetic resonance spectroscopy (MRS) defines neuro chemistry on a regional basis by acquiring a radiofrequency signal with chemical shift from one or many voxels or volumes previously selected on MRI. The tissue's chemical environment determines the frequency of a metabolite peak in an MRS spectrum. Candidates for MRS include: 1 H, 31 P, 13 C, 23 Na, 7 Li, 19 F, 14 N, 15 N, 17 O, 39 K The most commonly studied nuclei are 1 H and 31 P. This lecture is focused on Proton ( 1 H) Spectroscopy. Proton MRS can be added on to conventional MR imaging protocols. It can be used to serially monitor biochemical changes in tumors, stroke, epilepsy, metabolic disorders, infections, and neurodegenerative diseases.The MR spectra do not come labeled with diagnoses. They require interpretation and should always be correlated with the MR images before making a final diagnosis. As a general rule, the single voxel, short TE technique is used to make the initial diagnosis, because the signal-to-noise is high and all metabolites are represented. Multi-voxel, long TE techniques are used to further characterize different regions of a mass and to assess brain parenchyma around or adjacent to the mass. Multi-voxel, long TE techniques are also used to assess response to therapy and to search for tumor recurrence. Each metabolite appears at a specific ppm, and each one reflects specific cellular and biochemical processes

  9. Clinical application of functional magnetic resonance imaging

    International Nuclear Information System (INIS)

    Alwatban, Adnan Z.W.

    2002-01-01

    The work described in this thesis was carried out at the Magnetic Resonance Centre of the University of Nottingham during the time from May 1998 to April 2001, and is the work of the author except where indicated by reference. The main source of signal changes in functional magnetic resonance imaging (fMRJ) is the fluctuation of paramagnetic deoxyhaemoglobin in the venous blood during different states of functional performance. For the work of this thesis, fMRI studies were carried out using a 3 T MR system with an echo planar imaging (EPI) pulse sequence. Hearing research utilising fMRI has been previously reported in normal subjects. Hearing fMRI is normally performed by stimulating the auditory cortex via an acoustic task presentation such as music, tone, etc. However, performing the same research on deaf subjects requires special equipment to be designed to allow direct stimulation of the auditory nerve. In this thesis, a new method of direct electrical stimulation of the auditory nerve is described that uses a transtympanic electrode implanted onto the surface of the cochlea. This approach would however, result in electromotive forces (EMFs) being induced by the time varying magnetic field, which would lead to current flow and heating, as well as deflection of the metallic electrode within the static magnetic field, and image distortion due to the magnetic susceptibility difference. A gold-plated tungsten electrode with a zero magnetic susceptibility was developed to avoid image distortion. Used with carbon leads and a carbon reference pad, it enabled safe, distortion-free fMRI studies of deaf subjects. The study revealed activation of the primary auditory cortex. This fMRI procedure can be used to demonstrate whether the auditory pathway is fully intact, and may provide a useful method for pre-operative assessment of candidates for cochlear implantation. Glucose is the energy source on which the function of the human brain is entirely dependent. Failure to

  10. Clinical application of functional magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Alwatban, Adnan Z W

    2002-07-01

    The work described in this thesis was carried out at the Magnetic Resonance Centre of the University of Nottingham during the time from May 1998 to April 2001, and is the work of the author except where indicated by reference. The main source of signal changes in functional magnetic resonance imaging (fMRJ) is the fluctuation of paramagnetic deoxyhaemoglobin in the venous blood during different states of functional performance. For the work of this thesis, fMRI studies were carried out using a 3 T MR system with an echo planar imaging (EPI) pulse sequence. Hearing research utilising fMRI has been previously reported in normal subjects. Hearing fMRI is normally performed by stimulating the auditory cortex via an acoustic task presentation such as music, tone, etc. However, performing the same research on deaf subjects requires special equipment to be designed to allow direct stimulation of the auditory nerve. In this thesis, a new method of direct electrical stimulation of the auditory nerve is described that uses a transtympanic electrode implanted onto the surface of the cochlea. This approach would however, result in electromotive forces (EMFs) being induced by the time varying magnetic field, which would lead to current flow and heating, as well as deflection of the metallic electrode within the static magnetic field, and image distortion due to the magnetic susceptibility difference. A gold-plated tungsten electrode with a zero magnetic susceptibility was developed to avoid image distortion. Used with carbon leads and a carbon reference pad, it enabled safe, distortion-free fMRI studies of deaf subjects. The study revealed activation of the primary auditory cortex. This fMRI procedure can be used to demonstrate whether the auditory pathway is fully intact, and may provide a useful method for pre-operative assessment of candidates for cochlear implantation. Glucose is the energy source on which the function of the human brain is entirely dependent. Failure to

  11. Magnetic resonance imaging- physical principles and clinical application

    International Nuclear Information System (INIS)

    Tavri, Omprakash J.

    1996-01-01

    The advances in equipment and knowledge related to radiology are occurring at an astonishingly rapid rate. On November 8, 1895, William Conrad Roentgen discovered x-rays. In 1972, Godfrey Hounsfield and George Ambrose introduced computec tomography at a meeting of the British Institute of Radiology. In the same year, Paul Lauterbur published the idea of spatially resolving nuclear magnetic resonance samples, naming it zeugmatography. In 1977, Waldo Hinshaw and co-workers published a magnetic resonance image of a human hand and wrist, and by 1981 several centres were obtaining clinical magnetic resonance (MR) images. In a very short time, magnetic resonance imaging (MRI) has gained acceptance as a clinically useful imaging tool. (author)

  12. Magnetic resonance annual 1986

    International Nuclear Information System (INIS)

    Kressel, H.Y.

    1986-01-01

    This book contains papers written on magnetic resonance during 1986. Topics include: musculosketetal magnetic resonance imaging; imaging of the spine; magnetic resonance chemical shift imaging; magnetic resonance imaging in the central nervous system; comparison to computed tomography; high resolution magnetic resonance imaging using surface coils; magnetic resonance imaging of the chest; magnetic resonance imaging of the breast; magnetic resonance imaging of the liver; magnetic resonance spectroscopy of neoplasms; blood flow effects in magnetic resonance imaging; and current and potential applications of clinical sodium magnetic resonance imaging

  13. The introduction of clinical magnetic resonance imaging in Australia

    International Nuclear Information System (INIS)

    Sorby, W.; Baddeley, H.

    1986-01-01

    Magnetic resonance imaging is a new, but expensive, modality that is being introduced into clinical use in Australia. While it promises increased safety and accuracy in many situations, its precise role when compared with computed tomography and other modalities is not fully established. Therefore, a Government financed evaluation of costs and efficacy of magnetic resonance imaging units in five teaching hospitals is to be conducted over two years (1986-1988). Experience with the introduction of computed tomography to Australia and other nations has revealed difficulties in the evaluation by conventional methods of a diagnostic technology that is improving rapidly; it is to be hoped that a systematic evaluation of the clinical applications of magnetic resonance imaging will be more achievable and useful

  14. Normal feline brain: clinical anatomy using magnetic resonance imaging.

    Science.gov (United States)

    Mogicato, G; Conchou, F; Layssol-Lamour, C; Raharison, F; Sautet, J

    2012-04-01

    The purpose of this study was to provide a clinical anatomy atlas of the feline brain using magnetic resonance imaging (MRI). Brains of twelve normal cats were imaged using a 1.5 T magnetic resonance unit and an inversion/recovery sequence (T1). Fourteen relevant MRI sections were chosen in transverse, dorsal, median and sagittal planes. Anatomic structures were identified and labelled using anatomical texts and Nomina Anatomica Veterinaria, sectioned specimen heads, and previously published articles. The MRI sections were stained according to the major embryological and anatomical subdivisions of the brain. The relevant anatomical structures seen on MRI will assist clinicians to better understand MR images and to relate this neuro-anatomy to clinical signs. © 2011 Blackwell Verlag GmbH.

  15. Clinical applications of nuclear magnetic resonance spectroscopy: a review

    International Nuclear Information System (INIS)

    Newman, R.J.

    1984-01-01

    The advantages and present limitations of the clinical applications of nuclear magnetic resonance spectroscopy are reviewed in outline, with passing references to skeletal muscular studies, in particular a group of children with advanced Duchenne dystrophy, and the applications to the study of cerebral metabolism of neonates, excised kidneys, biopsy studies of breast and axillary lymph node samples, and NMR spectroscopy performed during chemotherapy of a secondary rhabdomyosarcoma in the skin. (U.K.)

  16. Clinical applications of nuclear magnetic resonance spectroscopy: a review

    Energy Technology Data Exchange (ETDEWEB)

    Newman, R.J. (Glasgow Western Infirmary (UK))

    1984-09-01

    The advantages and present limitations of the clinical applications of nuclear magnetic resonance spectroscopy are reviewed in outline, with passing references to skeletal muscular studies, in particular a group of children with advanced Duchenne dystrophy, and the applications to the study of cerebral metabolism of neonates, excised kidneys, biopsy studies of breast and axillary lymph node samples, and NMR spectroscopy performed during chemotherapy of a secondary rhabdomyosarcoma in the skin.

  17. Clinical applications of proton magnetic resonance spectroscopy of the brain

    International Nuclear Information System (INIS)

    Laubenberger, J.; Bayer, S.; Thiel, T.; Hennig, J.; Langer, M.

    1998-01-01

    In spite of all the scientific advances of the past few years, proton magnetic resonance spectroscopy of the brain has not attained the status of a routine examination technique with clinically accepted indications. The method should be considered as an additional option to MR imaging for inherited and acquired encephalopathic changes as well as, in future, for localization diagnosis of epilepsies. A proton magnetic resonance spectroscopic investigation without a prior intensive clinical and imaging investigation is not useful. Above all, factors influencing metabolite distribution such as for example, serum osmolability must be known. Methodological prerequisites for the clinical application of proton resonance spectroscopy are, first of all, a high stability of the chosen technique as well as a sufficiently certain quantification of metabolites and the availability of a reference group. The use of short echo times is necessary for the quantification of glutamine and the osmolyte myo-inositol. Indications for individual cases in which clinical investigations and MR topography cannot provide sufficient certainty and spectroscopy can furnish additional information are, in addition to uses in neuropediatrics, the suspicion of Alzheimer's dementia, HIV encephalopathy in early manifestations, and unclarified depressions of consciousness accompanying liver cirrhosis. (orig.) [de

  18. A comparison between clinical assessment and magnetic resonance imaging of acute hamstring injuries

    NARCIS (Netherlands)

    Schneider-Kolsky, Michal E.; Hoving, Jan Lucas; Warren, Price; Connell, David A.

    2006-01-01

    BACKGROUND: Physicians evaluating hamstring strains in professional football players are increasingly turning to magnetic resonance imaging to support the clinical diagnosis and management of the injury. However, little information is available to assess how magnetic resonance imaging compares with

  19. Clinical experience of magnetic resonance angiography in hand surgery

    International Nuclear Information System (INIS)

    Kawabata, Hidehiko; Yasui, Natsuo; Kitano, Motohiro; Sai, Eikoh

    1996-01-01

    Magnetic resonance angiography was performed in fourteen patients with congenital hand abnormalities. A two-dimentional time-of-flight imaging clearly demonstrated presence or absence of the radial, ulnar, and anterior interosseous arteires at forearm. However, smaller arteries such as digital arteries were depressed sometimes. This fact makes clinical application of the method somewhat limited. At present. appropriate applications in orthopaedic fields are evaluation of run-off of the major vessels after trauma or atherosclerotic diseases, venous vascular problems such as thrombophlebitis and aneurysm, and preoperative and post operative evaluation in microsurgery. If more detailed information is required, for example, in differential diagnosis of tumors conventional angiography or digital subtraction angiography is recommended. Because magnetic resonance angiography is non-invasive and does not need anesthesia, it is suitable especially for children. No requirement of contrast medium makes it easy to apply angiography to high risk patients and allergic patients to iodine. Technical advancement in near future will rise up magnetic resonance angiography to a standard evaluation method for vascular problems in orthopaedic fields very soon. (author)

  20. The clinical use of contrast agents in magnetic resonance imaging

    International Nuclear Information System (INIS)

    Bydder, G.M.

    1987-01-01

    Interest in the use of external agents to increase tissue contrasts has come from many sources dating back to the earliest work in NMR, to animal studies and to the widespread use of contrast agents in conventional radiological practice. The first clinical magnetic resonance images were published in 1980 and in the following year a brief account of the use of the paramagnetic agents in human volunteers was established. It was apparent relatively early in the development of magnetic resonance imaging (MRI) that a high level of soft tissue contrast was available de novo and the need for externally administered agents might therefore be small. This observation was tempered by the fact that separation of tumour from oedema was frequently better with contrast enhanced CT X-ray than with unenhanced MRI and that of a contrast agent might therefore be needed for MRI. At the end of 1983 the first parenteral agent gadoliminum diethylene triamine pentaacetic acid (Gd-DTPA) was used in volunteers and clinical studies began in 1984. At the present time only molecular O/sub 2/, oral iron compounds and Gd-DTPA are in clinical use although there are a number of other agents which have been used in animals and some of these may become available for clinical use in the foreseeable future

  1. Pediatric magnetic resonance imaging

    International Nuclear Information System (INIS)

    Cohen, M.D.

    1986-01-01

    This book defines the current clinical potential of magnetic resonance imaging and focuses on direct clinical work with pediatric patients. A section dealing with the physics of magnetic resonance imaging provides an introduction to enable clinicians to utilize the machine and interpret the images. Magnetic resonance imaging is presented as an appropriate imaging modality for pediatric patients utilizing no radiation

  2. Magnetic resonance imaging- physical principles and clinical application

    International Nuclear Information System (INIS)

    Tavri, O.J.

    1996-01-01

    The advances in imaging techniques for better and efficient diagnosis have become possible with the advent of Magnetic Resonance Imaging (MRI). The modalities of MRI technique for indication and diagnosis are mentioned in with typical examples. (author)

  3. Magnetic resonance spectroscopy in pediatric neuroradiology: clinical and research applications

    International Nuclear Information System (INIS)

    Panigrahy, Ashok; Nelson, Marvin D.; Blueml, Stefan

    2010-01-01

    Magnetic resonance spectroscopy (MRS) offers a unique, noninvasive approach to assess pediatric neurological abnormalities at microscopic levels by quantifying cellular metabolites. The most widely available MRS method, proton ( 1 H; hydrogen) spectroscopy, is FDA approved for general use and can be ordered by clinicians for pediatric neuroimaging studies if indicated. There are a multitude of both acquisition and post-processing methods that can be used in the implementation of MR spectroscopy. MRS in pediatric neuroimaging is challenging to interpret because of dramatic normal developmental changes that occur in metabolites, particularly in the first year of life. Still, MRS has been proven to provide additional clinically relevant information for several pediatric neurological disease processes such as brain tumors, infectious processes, white matter disorders, and neonatal injury. MRS can also be used as a powerful quantitative research tool. In this article, specific research applications using MRS will be demonstrated in relation to neonatal brain injury and pediatric brain tumor imaging. (orig.)

  4. Functional magnetic resonance in the conditions of a clinical department

    International Nuclear Information System (INIS)

    Obenberger, J.; Seidl, Z.; Krasensky, J.; Vitak, T.; Haberzettel, V.

    1997-01-01

    Functional magnetic resonance is a novel technique enabling non-invasive monitoring of the brain function and metabolism at a time resolution and spatial resolution unmatched by any other imaging technique. The principle of the method is outlined, and it is demonstrated that such demanding examinations can be performed using state-of-the-art MR instrumentation combined with conventional equipment and GE sequences available at normal clinical departments. The functional MR examination, which does not take a much longer time than routine examination, can be improved by fixing the patient's head. As a prerequisite for correlation, the MR instrument has to be interfaced to a computer, and suitable tools for mutual data correlation have to be created. (P.A.)

  5. Magnetic resonance cardiac perfusion imaging-a clinical perspective

    Energy Technology Data Exchange (ETDEWEB)

    Hunold, Peter; Schlosser, Thomas; Barkhausen, Joerg [University Hospital, Department of Diagnostic and Interventional Radiology and Neuroradiology, Essen (Germany)

    2006-08-15

    Coronary artery disease (CAD) with its clinical appearance of stable or unstable angina and acute myocardial infarction is the leading cause of death in developed countries. In view of increasing costs and the rising number of CAD patients, there has been a major interest in reliable non-invasive imaging techniques to identify CAD in an early (i.e. asymptomatic) stage. Since myocardial perfusion deficits appear very early in the ''ischemic cascade'', a major breakthrough would be the non-invasive quantification of myocardial perfusion before functional impairment might be detected. Therefore, there is growing interest in other, target-organ-specific parameters, such as relative and absolute myocardial perfusion imaging. Magnetic resonance (MR) imaging has been proven to offer attractive concepts in this respect. However, some important difficulties have not been resolved so far, which still causes uncertainty and prevents the broad application of MR perfusion imaging in a clinical setting. This review explores recent technical developments in MR hardware, software and contrast agents, as well as their impact on the current and future clinical status of MR imaging of first-pass myocardial perfusion imaging. (orig.)

  6. Magnetic resonance cardiac perfusion imaging-a clinical perspective

    International Nuclear Information System (INIS)

    Hunold, Peter; Schlosser, Thomas; Barkhausen, Joerg

    2006-01-01

    Coronary artery disease (CAD) with its clinical appearance of stable or unstable angina and acute myocardial infarction is the leading cause of death in developed countries. In view of increasing costs and the rising number of CAD patients, there has been a major interest in reliable non-invasive imaging techniques to identify CAD in an early (i.e. asymptomatic) stage. Since myocardial perfusion deficits appear very early in the ''ischemic cascade'', a major breakthrough would be the non-invasive quantification of myocardial perfusion before functional impairment might be detected. Therefore, there is growing interest in other, target-organ-specific parameters, such as relative and absolute myocardial perfusion imaging. Magnetic resonance (MR) imaging has been proven to offer attractive concepts in this respect. However, some important difficulties have not been resolved so far, which still causes uncertainty and prevents the broad application of MR perfusion imaging in a clinical setting. This review explores recent technical developments in MR hardware, software and contrast agents, as well as their impact on the current and future clinical status of MR imaging of first-pass myocardial perfusion imaging. (orig.)

  7. Magnetic resonance angiography: Physical principles and clinical applications

    International Nuclear Information System (INIS)

    Hausmann, R.; Mueller, E.

    1992-01-01

    Within the last four years magnetic resonance angiography (MRA) developed very rapidly towards a well accepted screening technique for vascular examinations as a fast add-on to conventional MR. This review describes the basic physical principles as well as the different methods like time-of-flight and phase-sensitive MRA for visualization of blood vessels. Different applications of 3D, 2D sequential and 3D multivolume MRA are shown from various regions of the head and body. A short outlock to quantitative flow measurments is given in the last chapter including some interesting applications of these techniques which show the still expanding potential of magnetic resonance. (orig.) [de

  8. Late whiplash syndrome: a clinical and magnetic resonance imaging study.

    Science.gov (United States)

    Bonuccelli, U; Pavese, N; Lucetti, C; Renna, M R; Gambaccini, G; Bernardini, S; Canapicchi, R; Carrozzi, L; Murri, L

    1999-01-01

    Cervical hyperextension injuries are common and are associated with significant morbidity. Clinically two syndromes are described: "acute" whiplash syndrome and "late" whiplash syndrome (in which the patients are still symptomatic after six months despite normal physical and radiological examination). In order to clarify the pathology of the persistent pain in late whiplash syndrome we performed a cervical spine magnetic resonance imaging (MRI) in 33 consecutive patients suffering from this condition. Twenty-six patients (78.8%) showed MRI abnormalities, the most common MRI finding (57.6%) was pre-existent spondylosis. Indeed, the group of patients with spondylosis and other MRI changes had higher clinical scores than those without MRI abnormalities as measured by a three-point grading system based upon the symptoms and signs shown. Several MRI changes, most of them already demonstrable by standard X-ray were seen among 33 patients suffering from late whiplash syndrome. Although no one of these findings appears to be specific and certainly related to the previous neck injury, they could represent a risk factor for a longer pain duration.

  9. Clinical application of magnetic resonance in acute traumatic brain injury

    Energy Technology Data Exchange (ETDEWEB)

    Morais, Dionei F.; Gaia, Felipe F.P. [Hospital de Base de Sao Jose do Rio Preto, SP (Brazil). Servico de Neurocirurgia]. E-mail: centro@cerebroecoluna.com.br; Spotti, Antonio R.; Tognola, Waldir A. [Faculdade de Medicina de Sao Jose do Rio Preto (FAMERP), SP (Brazil). Dept. de Ciencias Neurologicas; Andrade, Almir F. [Universidade de Sao Paulo (USP), SP (Brazil). Hospital das Clinicas. Dept. de Neurocirurgia da Emergencia

    2008-07-01

    Purpose: To evaluate the clinical applications of magnetic resonance imaging (MRI) in patients with acute traumatic brain injury (TBI): to identify the type, quantity, severity; and improvement clinical-radiological correlation. Method: Assessment of 55 patients who were imaged using CT and MRI, 34 (61.8%) males and 21 (38.2%) females, with acute (0 to 5 days) and closed TBI. Results: Statistical significant differences (McNemar test): occurred fractures were detected by CT in 29.1% and by MRI in 3.6% of the patients; subdural hematoma by CT in 10.9% and MRI in 36.4 %; diffuse axonal injury (DAI) by CT in 1.8% and MRI in 50.9%; cortical contusions by CT in 9.1% and MRI in 41.8%; subarachnoid hemorrhage by CT in 18.2% and MRI in 41.8%. Conclusion: MRI was superior to the CT in the identification of DAI, subarachnoid hemorrhage, cortical contusions, and acute subdural hematoma; however it was inferior in diagnosing fractures. The detection of DAI was associated with the severity of acute TBI. (author)

  10. Clinical application of magnetic resonance in acute traumatic brain injury

    International Nuclear Information System (INIS)

    Morais, Dionei F.; Gaia, Felipe F.P.; Spotti, Antonio R.; Tognola, Waldir A.; Andrade, Almir F.

    2008-01-01

    Purpose: To evaluate the clinical applications of magnetic resonance imaging (MRI) in patients with acute traumatic brain injury (TBI): to identify the type, quantity, severity; and improvement clinical-radiological correlation. Method: Assessment of 55 patients who were imaged using CT and MRI, 34 (61.8%) males and 21 (38.2%) females, with acute (0 to 5 days) and closed TBI. Results: Statistical significant differences (McNemar test): occurred fractures were detected by CT in 29.1% and by MRI in 3.6% of the patients; subdural hematoma by CT in 10.9% and MRI in 36.4 %; diffuse axonal injury (DAI) by CT in 1.8% and MRI in 50.9%; cortical contusions by CT in 9.1% and MRI in 41.8%; subarachnoid hemorrhage by CT in 18.2% and MRI in 41.8%. Conclusion: MRI was superior to the CT in the identification of DAI, subarachnoid hemorrhage, cortical contusions, and acute subdural hematoma; however it was inferior in diagnosing fractures. The detection of DAI was associated with the severity of acute TBI. (author)

  11. Clinically relevant magnetic resonance imaging (MRI) findings in ...

    African Journals Online (AJOL)

    Background: Shoulder pain is the most common and well-documented site of musculoskeletal pain in elite swimmers. Structural abnormalities on magnetic resonance imaging (MRI) of elite swimmers' symptomatic shoulders are common. Little has been documented about the association between MRI findings in the ...

  12. Radiofrequency solutions in clinical high field magnetic resonance

    NARCIS (Netherlands)

    Andreychenko, A.

    2013-01-01

    Magnetic resonance imaging (MRI) and spectroscopy (MRS) benefit from the sensitivity gain at high field (≥7T). However, high field brings also certain challenges associated with growing frequency and spectral dispersion. Frequency growth results in degraded performance of large volume radiofrequency

  13. Basic principles of magnetic resonance imaging in cerebral ischemia and initial clinical experience

    International Nuclear Information System (INIS)

    Brant-Zawadzki, M.; Solomon, M.; Newton, T.H.; Weinstein, P.; Schmidley, J.; Norman, D.

    1985-01-01

    The basic principles of magnetic resonance imaging are described and their use in the investigation of cerebral ischemia outlined. A brief account is given of the clinical results of investigation to date

  14. The clinical usefulness of magnetic resonance imaging for lung cancer

    International Nuclear Information System (INIS)

    Kobayashi, Hideo; Tanaka, Osamu; Hata, Enjyo; Fukushima, Kanae; Ishihara, Teruo; Matsuoka, Rokuro; Osawa, Tadashi; Kitamura, Satoshi

    1987-01-01

    Sixty patients with lung cancer, including 35 operated cases and 4 autopsy cases, were studied by magnetic resonance imaging (MRI). Transverse and coronal imaging were performed by spin-echo sequence with electrocardiogram gating. MRI clearly demonstrated the normal mediastinal and hilar structures. More than 90 % of pulmonary vessels and lobar bronchi were identified. Seventy six percent of mediastinal and hilar lymph nodes shown on resected materials to be over than 1 cm in diameter were detected, as compared to 82 % for hilar nodes alone. Staging for T factor, tumor size were fairly accurate but P factor was correctly diagnosed of 64 %. In atelectasis, the pulmonary artery was presented as a linear structure, and this finding has not been reported yet. Our experience suggests that MRI is useful for the diagnosis of atelectasis, vascular involvement, and hilar lymphadenopathy. (author)

  15. Disc pathology after whiplash injury. A prospective magnetic resonance imaging and clinical investigation

    International Nuclear Information System (INIS)

    Pettersson, K.; Hildingsson, C.; Toolanen, G.; Fagerlund, M.; Bjornebrink, J.

    1997-01-01

    Although disc pathology seems to be one contributing factor in the development of chronic symptoms after whiplash injury, it may be unnecessary to examine these patients in the acute phase with magnetic resonance imaging ; correlating initial symptoms and signs to magnetic resonance imaging findings is difficult because of the relatively high proportion of false-positive results. Magnetic resonance imaging is indicated later in the course of treatment in patients with persistent arm pain, neurologic deficits, or clinical signs of nerve root compression to diagnose disc herniations requiring surgery. (authors)

  16. Disc pathology after whiplash injury. A prospective magnetic resonance imaging and clinical investigation.

    Science.gov (United States)

    Pettersson, K; Hildingsson, C; Toolanen, G; Fagerlund, M; Björnebrink, J

    1997-02-01

    This study was used to evaluate the relationship between magnetic resonance imaging findings and clinical findings after whiplash injury. To identify initial soft-tissue damage after whiplash injury, the development of disc pathology, and the relationship of disc pathology to clinical findings. Although a few studies have reported pathological magnetic resonance imaging findings after whiplash injuries, there is no prospective study published to our knowledge. Thirty-nine patients, 20 women and 19 men with a mean age of 32 years, were treated for whiplash injury. Magnetic resonance imaging and clinical examination were performed in a blinded manner at a mean of 11 days after trauma. The procedure was repeated at a 2-year follow-up visit. Two patients could not be examined with the second magnetic resonance imaging because of claustrophobia and pregnancy, respectively. The authors found 13 patients (33%) with disc herniations with medullary (six cases) or dura (seven cases) impingement over the 2-year follow-up period. At the follow-up examination all patients with medullary impingement had persistent or increased symptoms, and three of 27 patients (11%) with no or slight changes on magnetic resonance imaging had persistent symptoms. No ligament injuries were diagnosed. Although disc pathology seems to be one contributing factor in the development of chronic symptoms after whiplash injury, it may be unnecessary to examine these patients in the acute phase with magnetic resonance imaging; correlating initial symptoms and signs to magnetic resonance imaging findings is difficult because of the relatively high proportion of false-positive results. Magnetic resonance imaging is indicated later in the course of treatment in patients with persistent arm pain, neurologic deficits or clinical signs of nerve root compression to diagnose disc herniations requiring surgery.

  17. Cardiovascular Magnetic Resonance in Cardiology Practice: A Concise Guide to Image Acquisition and Clinical Interpretation.

    Science.gov (United States)

    Valbuena-López, Silvia; Hinojar, Rocío; Puntmann, Valentina O

    2016-02-01

    Cardiovascular magnetic resonance plays an increasingly important role in routine cardiology clinical practice. It is a versatile imaging modality that allows highly accurate, broad and in-depth assessment of cardiac function and structure and provides information on pertinent clinical questions in diseases such as ischemic heart disease, nonischemic cardiomyopathies, and heart failure, as well as allowing unique indications, such as the assessment and quantification of myocardial iron overload or infiltration. Increasing evidence for the role of cardiovascular magnetic resonance, together with the spread of knowledge and skill outside expert centers, has afforded greater access for patients and wider clinical experience. This review provides a snapshot of cardiovascular magnetic resonance in modern clinical practice by linking image acquisition and postprocessing with effective delivery of the clinical meaning. Copyright © 2015 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

  18. Dedicated Magnetic Resonance Imaging in the Radiotherapy Clinic

    International Nuclear Information System (INIS)

    Karlsson, Mikael; Karlsson, Magnus G.; Nyholm, Tufve; Amies, Christopher; Zackrisson, Bjoern

    2009-01-01

    Purpose: To introduce a novel technology arrangement in an integrated environment and outline the logistics model needed to incorporate dedicated magnetic resonance (MR) imaging in the radiotherapy workflow. An initial attempt was made to analyze the value and feasibility of MR-only imaging compared to computed tomography (CT) imaging, testing the assumption that MR is a better choice for target and healthy tissue delineation in radiotherapy. Methods and Materials: A 1.5-T MR unit with a 70-cm-bore size was installed close to a linear accelerator, and a special trolley was developed for transporting patients who were fixated in advance between the MR unit and the accelerator. New MR-based workflow procedures were developed and evaluated. Results: MR-only treatment planning has been facilitated, thus avoiding all registration errors between CT and MR scans, but several new aspects of MR imaging must be considered. Electron density information must be obtained by other methods. Generation of digitally reconstructed radiographs (DRR) for x-ray setup verification is not straight forward, and reliable corrections of geometrical distortions must be applied. The feasibility of MR imaging virtual simulation has been demonstrated, but a key challenge to overcome is correct determination of the skeleton, which is often needed for the traditional approach of beam modeling. The trolley solution allows for a highly precise setup for soft tissue tumors without the invasive handling of radiopaque markers. Conclusions: The new logistics model with an integrated MR unit is efficient and will allow for improved tumor definition and geometrical precision without a significant loss of dosimetric accuracy. The most significant development needed is improved bone imaging.

  19. Dedicated magnetic resonance imaging in the radiotherapy clinic.

    Science.gov (United States)

    Karlsson, Mikael; Karlsson, Magnus G; Nyholm, Tufve; Amies, Christopher; Zackrisson, Björn

    2009-06-01

    To introduce a novel technology arrangement in an integrated environment and outline the logistics model needed to incorporate dedicated magnetic resonance (MR) imaging in the radiotherapy workflow. An initial attempt was made to analyze the value and feasibility of MR-only imaging compared to computed tomography (CT) imaging, testing the assumption that MR is a better choice for target and healthy tissue delineation in radiotherapy. A 1.5-T MR unit with a 70-cm-bore size was installed close to a linear accelerator, and a special trolley was developed for transporting patients who were fixated in advance between the MR unit and the accelerator. New MR-based workflow procedures were developed and evaluated. MR-only treatment planning has been facilitated, thus avoiding all registration errors between CT and MR scans, but several new aspects of MR imaging must be considered. Electron density information must be obtained by other methods. Generation of digitally reconstructed radiographs (DRR) for x-ray setup verification is not straight forward, and reliable corrections of geometrical distortions must be applied. The feasibility of MR imaging virtual simulation has been demonstrated, but a key challenge to overcome is correct determination of the skeleton, which is often needed for the traditional approach of beam modeling. The trolley solution allows for a highly precise setup for soft tissue tumors without the invasive handling of radiopaque markers. The new logistics model with an integrated MR unit is efficient and will allow for improved tumor definition and geometrical precision without a significant loss of dosimetric accuracy. The most significant development needed is improved bone imaging.

  20. A clinical study and the diagnosis in magnetic resonance imaging of renal scarring

    International Nuclear Information System (INIS)

    Tsugaya, Masayuki; Hirao, Noriaki; Ohtaguro, Kazuo; Kato, Jiro.

    1989-01-01

    Twenty-nine kidneys of seventeen patients (nine boys and eight girls) with vesicoureteral reflux and repeated urinary tract infection were studied by magnetic resonance imaging for diagnosis of renal scarring and correlation between clinical data and the degree renal scarring. Renal scarring is classified into three types according to findings in magnetic resonance imaging. The degree of renal scarring are classified into five grades according to traditional grading of intravenous pyelogram. If a fine deformity of calyx is shown on intravenous pyelogram, magnetic resonance imaging demonstrates renal scarring. Magnetic resonance imaging without irradiation is exceedingly valuable for the diagnosis of renal scarring. The appearances of magnetic resonance imaging were supported by X-ray computed tomography. There is a substantial correlation between serum creatinine and the grades of renal scarring by magnetic resonance imaging. There is a substantial correlation between fever attacks and the grade of renal scarring, and there is a significant reverse correlation between the age of the onset of upper urinary tract infection and the grade of renal scarring. It is suggested that upper urinary tract infection is the most significant factor in scar formation. (author)

  1. Magnetic resonance imaging

    International Nuclear Information System (INIS)

    Robertson, Angus

    1990-01-01

    An assessment is made of the clinical benefits of expensive diagnostic technology, such as the magnetic resonance imaging. It is concluded that to most radiologists, magnetic resonance imaging has a definite place in the diagnostic scenario, especially for demonstrating central nervous system lesions in multiple sclerosis. While it is recognized that medical and financial resources are limited, it is emphasised that the cost to society must be balanced against the patient benefit. 17 refs

  2. Magnetic resonance imaging in the differential diagnosis of true placenta accreta: a clinical case

    Directory of Open Access Journals (Sweden)

    E. V. Tarachkova

    2016-01-01

    Full Text Available True placenta accreta is the attachment of chorionic villi to the myometrium, possibly penetrating into the thickness of the myometrium and its outside, including through the serous tunic. The main current diagnostic techniques are considered to be ultrasonography, laboratory diagnosis (elevated human chorionic gonadotropin and placental lactogen levels, and clinical data (pain and vaginal discharge. Magnetic resonance imaging is deemed to be an adjuvant technique. By using a clinical example, this paper considers the capabilities of magnetic resonance imaging to diagnose this abnormality and to choose a right treatment policy. The abnormality is compared with the conditions (trophoblastic tumor and myoma with lysis that are similar in their diagnosis and magnetic resonance pattern. The disorder in question is rather rare and its detailed consideration, determination of the capabilities of various techniques, and comparison with externally similar cases areimportant for the development of diagnostic opportunities.

  3. 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 ...

  4. Loop radiofrequency coils for clinical magnetic resonance imaging at 7 tesla

    NARCIS (Netherlands)

    Kraff, O.

    2011-01-01

    To date, the 7 T magnetic resonance imaging (MRI) scanner remains a pure research system and there is still a long way ahead till full clinical integration. Key challenges are the absence of a body transmit radiofrequency (RF) coil as well as of dedicated RF coils in general, short RF wavelengths of

  5. Clinical safety of magnetic resonance imaging in patients with implanted SynchroMed EL infusion pumps

    International Nuclear Information System (INIS)

    Diehn, Felix E.; Wood, Christopher P.; Watson, Robert E.; Hunt, Christopher H.; Mauck, William D.; Burke, Michelle M.

    2011-01-01

    Patients with implanted SynchroMed spinal infusion pumps (Medtronic, Inc., Minneapolis, MN) routinely undergo magnetic resonance imaging at our institution. In August 2008, Medtronic issued an urgent medical device correction report regarding several pumps. Because of the rare potential ''for a delay in the return of proper drug infusion'' and ''for a delay in the logging of motor stall events,'' ''a patient's pump must be interrogated after MRI exposure in order to confirm proper pump functionality.'' This is particularly important in patients receiving intrathecal baclofen, for whom a delay in return of proper pump infusion could lead to life-threatening baclofen withdrawal syndrome. The objective of this report is to present our experience and protocol of performing magnetic resonance imaging in patients with implanted SynchroMed EL pumps. We retrospectively reviewed records of 86 patients with implanted SynchroMed EL spinal infusion pumps who underwent 112 examinations on 1.5-T magnetic resonance imaging scanners from September 1, 1998 to July 7, 2004. No SynchroMed EL pumps were damaged by magnetic resonance imaging, and the programmable settings remained unchanged in all patients. Our data suggest that SynchroMed EL pump malfunction is indeed rare after routine clinical 1.5-T magnetic resonance imaging examinations. However, based on the Medtronic correction report, we perform pump interrogation before and after imaging. (orig.)

  6. Clinical safety of magnetic resonance imaging in patients with implanted SynchroMed EL infusion pumps

    Energy Technology Data Exchange (ETDEWEB)

    Diehn, Felix E.; Wood, Christopher P.; Watson, Robert E.; Hunt, Christopher H. [Mayo Clinic, Department of Radiology, Rochester, MN (United States); Mauck, William D. [Mayo Clinic, Department of Anesthesiology, Rochester, MN (United States); Burke, Michelle M. [Mayo Clinic, Department of Psychiatry and Psychology, Rochester, MN (United States)

    2011-02-15

    Patients with implanted SynchroMed spinal infusion pumps (Medtronic, Inc., Minneapolis, MN) routinely undergo magnetic resonance imaging at our institution. In August 2008, Medtronic issued an urgent medical device correction report regarding several pumps. Because of the rare potential ''for a delay in the return of proper drug infusion'' and ''for a delay in the logging of motor stall events,'' ''a patient's pump must be interrogated after MRI exposure in order to confirm proper pump functionality.'' This is particularly important in patients receiving intrathecal baclofen, for whom a delay in return of proper pump infusion could lead to life-threatening baclofen withdrawal syndrome. The objective of this report is to present our experience and protocol of performing magnetic resonance imaging in patients with implanted SynchroMed EL pumps. We retrospectively reviewed records of 86 patients with implanted SynchroMed EL spinal infusion pumps who underwent 112 examinations on 1.5-T magnetic resonance imaging scanners from September 1, 1998 to July 7, 2004. No SynchroMed EL pumps were damaged by magnetic resonance imaging, and the programmable settings remained unchanged in all patients. Our data suggest that SynchroMed EL pump malfunction is indeed rare after routine clinical 1.5-T magnetic resonance imaging examinations. However, based on the Medtronic correction report, we perform pump interrogation before and after imaging. (orig.)

  7. Magnetic resonance imaging

    International Nuclear Information System (INIS)

    Anon.

    1988-01-01

    Magnetic resonance imaging (MRI) is a new and innovative technique that affords anatomic images in multiple planes and that may provide information about tissue characterization. The magnetic resonance images are obtained by placing the patient or the area of interest within a powerful, highly uniform, static magnetic field. Magnetized protons (hydrogen nuclei) within the patient align like small magnets in this field. Radiofrequency pulses are then used to create an oscillating magnetic field perpendicular to the main field. Magnetic resonance images differ from those produced by x-rays: the latter are associated with absorption of x-ray energy while magnetic resonance images are based on proton density and proton relaxation dynamics. Proton characteristics vary according to the tissue under examination and reflect its physical and chemical properties. To resolve issues regarding safety and efficacy, the Warren Grant Magnuson Clinical Center and the Office of Medical Applications of Research of the National Institutes of Health (NIH) convened a consensus conference about MRI Oct 26 through 28, 1987. At the NIH, the Consensus Development Conference brings together investigators in the biomedical sciences, clinical investigators, practicing physicians, and consumer and special interest groups to make a scientific assessment of technologies, including drugs, devices, and procedures, and to seek agreement on their safety and effectiveness

  8. Magnetic Resonance Imaging in Malawi: Contributions to Clinical ...

    African Journals Online (AJOL)

    Michigan State University, Department of Radiology, Radiology 184,. East Lansing, MI 48824-USA. 2. .... reviews be permitted to use MRI data free of charge? Should authors of .... chemistry, and clinical hematology). This rare combination.

  9. Joubert syndrome: Clinical manifestations and magnetic resonance imaging

    International Nuclear Information System (INIS)

    Kim, Seung Cheol; Kim, In One; Yoon, Yong Kyu; Yeon, Kyung Mo; Kim, Woo Sun; Song, Jong Gi; Hwang, Yong Seung

    1994-01-01

    Joubert syndrome presents neonatal respiratory abnormalities and other clinical manifestations. Pathologically the patients show hypoplasia or agenesis of cerebellar vermis and other intracranial anomalies. Our purpose is to evaluate the clinical manifestations and MR findings of Joubert syndrome. Among the patient presenting with clinical stigmata of Joubert syndrome and agenesis of vermis on MR imaging, eight patients who did not satisfied the criteria of Dandy-Walker malformation, tectocerebellar dysraphia and rhombencephalosynapsis were selected. MR findings and clinical manifestation were analyzed. On MR imaging, agenesis of the cerebellar vermis (all cases), hypoplasia of the cerebellar peduncle (6 cases), fourth ventricular contour deformity (6 cases), tentorial elevation (4 caes), deformity of the lateral ventricles (4 cases), dysgenesis of the straight sinus (3 cases) were demonstrated. Other findings were abnormalities of corpus callosum (3 cases), falx anomalies (3 case), occipital encephalomeningocele (2 cases) and fluid collection in posterior cranial fossa (2 cases). Clinical manifestations were developmental delay (5 cases), abnormal eyeball movement (3 cases), hypotonia (2 cases), neonatal respiratory abnormality (2 cases), etc. Joubert syndrome showed various clinical manifestations and intracranial anomalies. MR imaging is an useful modality in detection of the cerebellar vermian agenesis and other anomalies of the patients

  10. ST-Segment resolution and clinical outcome with ischemic postconditioning and comparison to magnetic resonance

    DEFF Research Database (Denmark)

    Lønborg, Jacob; Holmvang, Lene; Kelbæk, Henning

    2010-01-01

    Ischemic postconditioning (IPost) during primary percutaneous coronary intervention (PPCI) is suggested to reduce myocardial damage. However, the association with ST-segment resolution (STR) and clinical outcome is not determined. The primary aim of this study was to evaluate the association of I...... of IPost with STR and clinical outcome. Secondly, we sought to determine the relationship between STR and cardiac magnetic resonance (CMR) parameters in these patients....

  11. Clinically low-risk prostate cancer: evaluation with transrectal doppler ultrasound and functional magnetic resonance imaging

    Directory of Open Access Journals (Sweden)

    Maria Inês Novis

    2011-01-01

    Full Text Available OBJECTIVES: To evaluate transrectal ultrasound, amplitude Doppler ultrasound, conventional T2-weighted magnetic resonance imaging, spectroscopy and dynamic contrast-enhanced magnetic resonance imaging in localizing and locally staging low-risk prostate cancer. INTRODUCTION: Prostate cancer has been diagnosed at earlier stages and the most accepted classification for low-risk prostate cancer is based on clinical stage T1c or T2a, Gleason score <6, and prostate-specific antigen (PSA <10 ng/ml. METHODS: From 2005 to 2006, magnetic resonance imaging was performed in 42 patients, and transrectal ultrasound in 26 of these patients. Seven patients were excluded from the study. Mean patient age was 64.94 years and mean serum PSA was 6.05 ng/ml. The examinations were analyzed for tumor identification and location in prostate sextants, detection of extracapsular extension, and seminal vesicle invasion, using surgical pathology findings as the gold standard. RESULTS: Sixteen patients (45.7% had pathologically proven organ-confined disease, 11 (31.4% had positive surgical margin, 8 (28.9% had extracapsular extension, and 3 (8.6% presented with extracapsular extension and seminal vesicle invasion. Sensitivity, specificity, positive predictive value (PPV, negative predictive value (NPV and accuracy values for localizing low-risk prostate cancer were 53.1%, 48.3%, 63.4%, 37.8% and 51.3% for transrectal ultrasound; 70.4%, 36.2%, 65.1%, 42.0% and 57.7% for amplitude Doppler ultrasound; 71.5%, 58.9%, 76.6%, 52.4% and 67.1% for magnetic resonance imaging; 70.4%, 58.7%, 78.4%, 48.2% and 66.7% for magnetic resonance spectroscopy; 67.2%, 65.7%, 79.3%, 50.6% and 66.7% for dynamic contrast-enhanced magnetic resonance imaging, respectively. Sensitivity, specificity, PPV, NPV and accuracy values for detecting extracapsular extension were 33.3%, 92%, 14.3%, 97.2% and 89.7% for transrectal ultrasound and 50.0%, 77.6%, 13.7%, 95.6% and 75.7% for magnetic resonance imaging

  12. Magnetic resonance annual, 1988

    International Nuclear Information System (INIS)

    Kressel, H.Y.

    1987-01-01

    This book features reviews of high-resolution MRI of the knee, MRI of the normal and ischmeic hip, MRI of the heart, and temporomandibular joint imaging, as well as thorough discussion on artifacts in magnetic resonance imaging. Contributors consider the clinical applications of gadolinium-DTPA in magnetic resonance imaging and the clinical use of partial saturation and saturation recovery sequences. Timely reports assess the current status of rapid MRI and describe a new rapid gated cine MRI technique. Also included is an analysis of cerebrospinal fluid flow effects during MRI of the central nervous system

  13. REVIEW Magnetic resonance imaging of the breast: A clinical ...

    African Journals Online (AJOL)

    and it increases the number of mastectomies being performed. The available data suggest that the change in management of patients following an MRI will not increase their survival. Case 1. A 40-year-old woman presented with a mass in her left breast. Clinically the mass was consistent with a benign process. Her.

  14. Nuclear magnetic resonance imaging

    International Nuclear Information System (INIS)

    1983-06-01

    This report summarises the aspects of nuclear magnetic resonance imaging (NMRI) considered by the National Health Technology Advisory Panel and makes recommendations on its introduction in Australia with particular regard to the need for thorough evaluation of its cost effectiveness. Topics covered are: principles of the technique, equipment required, installation, costs, reliability, performance parameters, clinical indications, training and staff requirements, and safety considerations

  15. Assmentment of myocardial perfusion by magnetic resonance imaging: on the way to clinical application

    International Nuclear Information System (INIS)

    Fischer, S.E.; Lorenz, C.H.

    1997-01-01

    Magnetic resonance imaging detects the flow of contrast - enhanced blood and even allows the quantitative assessment of myocardial perfusion. The clinical application of this method is being held back by the difficulties in image evaluation and the limitation of standard techniques to the acquisition of a single slice per heart beat cycle. Recent developments in scanner hardware as well as in image acquisition techniques open up the possibility of assessing myocardial perfusion over the entire heart with a spatial resolution in the range of 2 mm. As an example of such a new scanning strategy, a segmented gradient-echo recalled echo planar imaging sequence with preceding saturation is discussed and results in a patient with an infarction are presented. The clinical use of perfusion assessment covering the entire heart for the diagnosis of coronary artery disease is enhanced by the flexibility of magnetic resonance imaging for the assessment of functional cardiac parameters. (orig.) [de

  16. Automated Modular Magnetic Resonance Imaging Clinical Decision Support System (MIROR): An Application in Pediatric Cancer Diagnosis.

    Science.gov (United States)

    Zarinabad, Niloufar; Meeus, Emma M; Manias, Karen; Foster, Katharine; Peet, Andrew

    2018-05-02

    Advances in magnetic resonance imaging and the introduction of clinical decision support systems has underlined the need for an analysis tool to extract and analyze relevant information from magnetic resonance imaging data to aid decision making, prevent errors, and enhance health care. The aim of this study was to design and develop a modular medical image region of interest analysis tool and repository (MIROR) for automatic processing, classification, evaluation, and representation of advanced magnetic resonance imaging data. The clinical decision support system was developed and evaluated for diffusion-weighted imaging of body tumors in children (cohort of 48 children, with 37 malignant and 11 benign tumors). Mevislab software and Python have been used for the development of MIROR. Regions of interests were drawn around benign and malignant body tumors on different diffusion parametric maps, and extracted information was used to discriminate the malignant tumors from benign tumors. Using MIROR, the various histogram parameters derived for each tumor case when compared with the information in the repository provided additional information for tumor characterization and facilitated the discrimination between benign and malignant tumors. Clinical decision support system cross-validation showed high sensitivity and specificity in discriminating between these tumor groups using histogram parameters. MIROR, as a diagnostic tool and repository, allowed the interpretation and analysis of magnetic resonance imaging images to be more accessible and comprehensive for clinicians. It aims to increase clinicians' skillset by introducing newer techniques and up-to-date findings to their repertoire and make information from previous cases available to aid decision making. The modular-based format of the tool allows integration of analyses that are not readily available clinically and streamlines the future developments. ©Niloufar Zarinabad, Emma M Meeus, Karen Manias

  17. Clinical relevance of magnetic resonance imaging and magnetic resonance spectroscopy for the cirrhotic without overt hepatic encephalopathy

    Energy Technology Data Exchange (ETDEWEB)

    Fujishima, Yukou; Kato, Akinobu; Suzuki, Kazuyuki [Iwate Medical Univ., Morioka (Japan). School of Medicine

    1999-04-01

    To clarify the changes of pallidal high intensity on T1-weighted magnetic resonance imaging (MRI) and brain metabolites on magnetic resonance spectroscopy (MRS) as related to the severity of hepatic functions, the concentrations of blood ammonia (B-NH{sub 3}) and the levels of trace elements (Mn, Cu and Zn), 30 patients with liver cirrhosis without hepatic encephalopathy (HE) and 5 age-matched healthy control subjects underwent MRI and proton MRS. Pallidal high intensity (Pl index) and glutamine are higher in cirrhosis, and myo-inositol is lower than that of control statistically. In cirrhosis, there were statistically negative correlation between B-NH{sub 3} and myo-inositol and positive correlation between B-NH{sub 3} and glutamine. There was a statistically lower myo-inositol and higher Pl index, glutamine as the severity of hepatic functions increased. Furthermore there was a statistically positive correlation between Pl index and Mn. These data suggest that the changes of MRI and MRS findings already detected in cirrhosis without HE and these abnormalities may be reflect the B-NH{sub 3} and Mn metabolism and the severity of the hepatic functions. (author)

  18. Clinical relevance of magnetic resonance imaging and magnetic resonance spectroscopy for the cirrhotic without overt hepatic encephalopathy

    International Nuclear Information System (INIS)

    Fujishima, Yukou; Kato, Akinobu; Suzuki, Kazuyuki

    1999-01-01

    To clarify the changes of pallidal high intensity on T1-weighted magnetic resonance imaging (MRI) and brain metabolites on magnetic resonance spectroscopy (MRS) as related to the severity of hepatic functions, the concentrations of blood ammonia (B-NH 3 ) and the levels of trace elements (Mn, Cu and Zn), 30 patients with liver cirrhosis without hepatic encephalopathy (HE) and 5 age-matched healthy control subjects underwent MRI and proton MRS. Pallidal high intensity (Pl index) and glutamine are higher in cirrhosis, and myo-inositol is lower than that of control statistically. In cirrhosis, there were statistically negative correlation between B-NH 3 and myo-inositol and positive correlation between B-NH 3 and glutamine. There was a statistically lower myo-inositol and higher Pl index, glutamine as the severity of hepatic functions increased. Furthermore there was a statistically positive correlation between Pl index and Mn. These data suggest that the changes of MRI and MRS findings already detected in cirrhosis without HE and these abnormalities may be reflect the B-NH 3 and Mn metabolism and the severity of the hepatic functions. (author)

  19. Reliability of clinical findings and magnetic resonance imaging for the diagnosis of chondromalacia patellae.

    Science.gov (United States)

    Pihlajamäki, Harri K; Kuikka, Paavo-Ilari; Leppänen, Vesa-Veikko; Kiuru, Martti J; Mattila, Ville M

    2010-04-01

    This diagnostic study was performed to determine the correlation between anterior knee pain and chondromalacia patellae and to define the reliability of magnetic resonance imaging for the diagnosis of chondromalacia patellae. Fifty-six young adults (median age, 19.5 years) with anterior knee pain had magnetic resonance imaging of the knee followed by arthroscopy. The patellar chondral lesions identified by magnetic resonance imaging were compared with the arthroscopic findings. Arthroscopy confirmed the presence of chondromalacia patellae in twenty-five (45%) of the fifty-six knees, a synovial plica in twenty-five knees, a meniscal tear in four knees, and a femorotibial chondral lesion in four knees; normal anatomy was seen in six knees. No association was found between the severity of the chondromalacia patellae seen at arthroscopy and the clinical symptoms of anterior knee pain syndrome (p = 0.83). The positive predictive value for the ability of 1.0-T magnetic resonance imaging to detect chondromalacia patellae was 75% (95% confidence interval, 53% to 89%), the negative predictive value was 72% (95% confidence interval, 56% to 84%), the sensitivity was 60% (95% confidence interval, 41% to 77%), the specificity was 84% (95% confidence interval, 67% to 93%), and the diagnostic accuracy was 73% (95% confidence interval, 60% to 83%). The sensitivity was 13% (95% confidence interval, 2% to 49%) for grade-I lesions and 83% (95% confidence interval, 59% to 94%) for grade-II, III, or IV lesions. Chondromalacia patellae cannot be diagnosed on the basis of symptoms or with current physical examination methods. The present study demonstrated no correlation between the severity of chondromalacia patellae and the clinical symptoms of anterior knee pain syndrome. Thus, symptoms of anterior knee pain syndrome should not be used as an indication for knee arthroscopy. The sensitivity of 1.0-T magnetic resonance imaging was low for grade-I lesions but considerably higher for more

  20. Clinical, radiographic, and magnetic resonance imaging findings of gastrocnemius musculotendinopathy in various dog breeds.

    Science.gov (United States)

    Kaiser, Susanne M; Harms, Oliver; Konar, Martin; Staudacher, Anne; Langer, Anna; Thiel, Cetina; Kramer, Martin; Schaub, Sebastian; von Pückler, Kerstin H

    2016-11-23

    To describe clinical, radiographic, and magnetic resonance imaging (MRI) findings in 16 dogs diagnosed with gastrocnemius musculotendinopathy. Retrospective evaluation of medical records, radiographs, and MRI results, as well as follow-up completed by telephone questionnaire. Most dogs had chronic hindlimb lameness with no history of trauma or athletic activities. Clinical examination revealed signs of pain on palpation without stifle joint instability. Seven dogs had radiographic signs of osteophyte formation on the lateral fabella. Magnetic resonance imaging revealed T2 hyperintensity and uptake of contrast agent in the region of the origin of the gastrocnemius muscle. Changes were found in the lateral and medial heads of the gastrocnemius. Conservative treatment resulted in return to full function in 11 dogs. Two dogs showed partial restoration of normal function, one dog showed no improvement. Two dogs were lost to follow-up. Gastrocnemius musculotendinopathy is a potential cause of chronic hindlimb lameness in medium to large breed dogs. A history of athletic activity must not necessarily be present. Magnetic resonance imaging shows signal changes and uptake of contrast agent in the region of the origin of the gastrocnemius muscle. A combination of T1 pre- and post-contrast administration and T2 weighted sequences completed by a fat-suppressed sequence in the sagittal plane are well-suited for diagnosis. Conservative treatment generally results in return to normal function.

  1. Comparison of magnetic resonance angiography and conventional angiography in sickle cell disease: clinical significance and realibility

    International Nuclear Information System (INIS)

    Kandeel, A.Y.; Zimmerman, R.A.; Ohene-Frempong, K.

    1996-01-01

    We retrospectively reviewed the medical records and conventional angiograms of 21 patients with known sickle cell disease, who underwent a total of 50 magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) studies. MRA and conventional angiography were assessed separately for evidence of stenosis or occulusion. Follow up MRI/MRA studies were also assessed for evidence of progression, regression or stability of the disease in these patients. In the carotid circulation, MRA made the correct diagnosis in 85% of the vessels evaluated with a sensitivity of 80.5% and a specificity of 94%. MRA was also found to show evidence of disease progression, more often than did MRI or the clinical condition of the patients. (orig.)

  2. Magnetic resonance imaging and clinical findings in a miniature Schnauzer with hypodipsic hypernatremia

    International Nuclear Information System (INIS)

    Shimokawa Miyama, Takako; Iwamoto, Emiko; Umeki, Saori; Nakaichi, Munekazu; Okuda, Masaru; Mizuno, Takuya

    2009-01-01

    A 6-month-old miniature Schnauzer presented with hypernatremia and clinical signs of vomiting, diarrhea, inappetence, and lethargy. The dog did not consume water on its own. Hypernatremia and the related clinical signs were resolved by fluid administration. Endocrinological investigations and urinalysis excluded the possibility of diabetes insipidus and hyperaldosteronism. Therefore, the dog was diagnosed with hypodipsic hypernatremia. Magnetic resonance imaging revealed dysgenesis of the corpus callosum and other forebrain structures. On the basis of these findings, congenital brain malformation associated with failure of the osmoreceptor system was suspected. (author)

  3. Magnetic resonance imaging and clinical findings in a miniature Schnauzer with hypodipsic hypernatremia.

    Science.gov (United States)

    Shimokawa Miyama, Takako; Iwamoto, Emiko; Umeki, Saori; Nakaichi, Munekazu; Okuda, Masaru; Mizuno, Takuya

    2009-10-01

    A 6-month-old miniature Schnauzer presented with hypernatremia and clinical signs of vomiting, diarrhea, inappetence, and lethargy. The dog did not consume water on its own. Hypernatremia and the related clinical signs were resolved by fluid administration. Endocrinological investigations and urinalysis excluded the possibility of diabetes insipidus and hyperaldosteronism. Therefore, the dog was diagnosed with hypodipsic hypernatremia. Magnetic resonance imaging revealed dysgenesis of the corpus callosum and other forebrain structures. On the basis of these findings, congenital brain malformation associated with failure of the osmoreceptor system was suspected.

  4. The Role of Clinical Cardiac Magnetic Resonance Imaging in China: Current Status and the Future

    Directory of Open Access Journals (Sweden)

    Shi Chen, MD

    2016-12-01

    Full Text Available Cardiac magnetic resonance (CMR imaging plays an important role in the diagnosis and management of cardiovascular diseases. The state-of-the-art CMR imaging has many advantages in cardiac imaging, including excellent spatial and temporal resolution, unrestricted imaging field, no exposure to ionizing radiation, excellent tissue contrast, and unique myocardial tissue characterization. Clinical CMR imaging is used during the cardiovascular diagnostic workup in the United States and some European countries. Use of CMR imaging is emerging in hospitals in China and has a promising future. This review briefly describes the real-world clinical application of CMR imaging in China and discuss obstacles for its future development.

  5. Relationship between external anal sphincter atrophy at endoanal magnetic resonance imaging and clinical, functional, and anatomic characteristics in patients with fecal incontinence

    NARCIS (Netherlands)

    Terra, Maaike P.; Deutekom, Marije; Beets-Tan, Regina G. H.; Engel, Alexander F.; Janssen, Lucas W. M.; Boeckxstaens, Guy E. E.; Dobben, Annette C.; Baeten, Cor G. M. I.; de Priester, Jacobus A.; Bossuyt, Patrick M. M.; Stoker, Jaap

    2006-01-01

    PURPOSE: External anal sphincter atrophy at endoanal magnetic resonance imaging has been associated with poor outcome of anal sphincter repair. We studied the relationship between external anal sphincter atrophy on endoanal magnetic resonance imaging and clinical, functional, and anatomic

  6. Clinical and magnetic resonance imaging correlation in acute spinal cord injury

    International Nuclear Information System (INIS)

    Ramon, S.; Dominguez, R.; Ramirez, L.; Garcia Fernandez, L.

    1998-01-01

    The aim of this study was to correlate traumatic spinal cord injury (SCI) patients'outcome with magnetic resonance imaging (MRI) performed within the first 15 days following trauma. We retrospectively analyzed 55 SCI patients. Early functional prognosis may be established on the basis of clinical presentation of SCI and associated MRI. Cord hemorrhage and transection are irreversible, while edema has a potential for neurological recovery. Cord contusion tends to be associated with an incomplete SCI, unlike the compression pattern, in which the prognosis depends on the degree of the initial neurological damage. (author)

  7. Giant intracranial aneurysms; Magnetic resonance imaging follow-up and clinical symptoms

    Energy Technology Data Exchange (ETDEWEB)

    Kondoh, Takeshi; Fujita, Katsuzo; Tamaki, Norihiko; Matsumoto, Satoshi [Kobe Univ. (Japan). School of Medicine; Yamashita, Haruo; Shirakata, Masaya

    1991-06-01

    Twenty-four intracranial aneurysms over 20 mm in diameter were studied with magnetic resonance (MR) imaging. MR imaging follow-up of eight cases revealed induced thrombus with homogeneous intensity and decreased size even after complete intraluminal thrombosis. Most cases demonstrated homogeneous intensity thrombus in contrast to the heterogeneous intensity of spontaneous thrombus. The clinical symptoms could not be explained retrospectively by the thrombus characteristics. Perianeurysmal high intensity, indicating cerebral edema, was detected in one case presenting with a rapid increase in size. MR imaging is useful for following these pathological intra- and perianeurysmal changes. (author).

  8. Physiological and technical limitations of functional magnetic resonance imaging (fMRI) - consequences for clinical use

    International Nuclear Information System (INIS)

    Wuestenberg, T.; Jordan, K.; Giesel, F.L.; Villringer, A.

    2003-01-01

    Functional magnetic resonance imaging (fMRI) is the most common noninvasive technique in functional neuroanatomy. The capabilities and limitations of the method will be discussed based on a short review of the current knowledge about the neurovascular relationship. The focus of this article is on current methodical and technical problems regarding fMRI-based detection and localization of neuronal activity. Main error sources and their influence on the reliability and validity of fMRI-methods are presented. Appropriate solution strategies will be proposed and evaluated. Finally, the clinical relevance of MR-based diagnostic methods are discussed. (orig.) [de

  9. Clinical and magnetic resonance imaging correlation in acute spinal cord injury

    Energy Technology Data Exchange (ETDEWEB)

    Ramon, S.; Dominguez, R.; Ramirez, L.; Garcia Fernandez, L. [University Hospital Vall d`Hebron, Barcelona (Spain)

    1998-04-01

    The aim of this study was to correlate traumatic spinal cord injury (SCI) patients`outcome with magnetic resonance imaging (MRI) performed within the first 15 days following trauma. We retrospectively analyzed 55 SCI patients. Early functional prognosis may be established on the basis of clinical presentation of SCI and associated MRI. Cord hemorrhage and transection are irreversible, while edema has a potential for neurological recovery. Cord contusion tends to be associated with an incomplete SCI, unlike the compression pattern, in which the prognosis depends on the degree of the initial neurological damage. (author)

  10. Lactate quantification by proton magnetic resonance spectroscopy using a clinical MRI machine: a basic study

    International Nuclear Information System (INIS)

    Isobe, T.; Muraishi, H.; Matsumura, A.; Kawamura, H.; Shibata, Y.; Anno, I.; Minami, M.

    2007-01-01

    The purpose of this study was to establish quantification method of lactate concentration by proton magnetic resonance spectroscopy (MRS) carried out using a conventional 1.5-T MRI machine. We used a lactate phantom with known concentrations (1, 1.5, 3, 6, 12 and 14 mmol/L). As a clinical example, a patient with mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS) was evaluated. Proton MRS was carried out using a clinical 1.5-T super-conducting magnetic resonance whole-body system. Data were acquired by point resolved spectroscopy. A coupling constant of J = 7.35 Hz (2/7 = 272 ms) and two long in-phase echo time of 272 ms and 544 ms were used to calculate the T2 relaxation time. The tissue water signal was used as an internal standard to quantify lactate. The correlation coefficient R between the calculated lactate concentrations and the known concentration of lactate was 0.99 with a constant factor of 0.32 (1/3.14). In patients with MELAS, the lactate concentration measured by MRS was 6.2 mmol/kg wet weight, which is similar to the value obtained in previous studies. In the present study, we have established a reliable method for lactate quantification in a phantom study and have shown a sample of clinical case of MELAS

  11. A comparison of clinical symptoms and magnetic resonance images in temporomandibular joint disorders

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Yong Suk; Hwang, Eui Hwan; Lee, Sang Rae [Kyunghee University College of Medicine, Seoul (Korea, Republic of)

    2003-06-15

    To determine the relationship between clinical symptoms and magnetic resonance (MR) images in patients presenting with temporomandibular joint (TMJ) disorders. This study was based on 172 joints in 86 patients presenting with TMJ disorders. Joint pain and sound during jaw opening and closing movements were recorded, and the possible relationship between disc positions and bony changes of the condylar head and the articular fossa in MR images in the oblique sagittal planes were examined. Data were analyzed by Chi-square test. There was no statistically significant relationship between clinical symptoms and MR images in the patients with TMJ disorders. In the patient with TMJ disorders, joint pain and sound could not be specific clinical symptoms that are related with MR image findings, and asymptomatic joint did not necessarily imply that the joints are normal according to MR image findings.

  12. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    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 ...

  13. Magnetic resonance imaging apparatus

    International Nuclear Information System (INIS)

    Ehnholm, G.J.

    1991-01-01

    This patent describes an electron spin resonance enhanced magnetic resonance (MR) imaging (ESREMRI) apparatus able to generate a primary magnetic field during periods of nuclear spin transition excitation and magnetic resonance signal detection. This allows the generation of ESREMRI images of a subject. A primary magnetic field of a second and higher value generated during periods of nuclear spin transition excitation and magnetic resonance signal detection can be used to generate conventional MR images of a subject. The ESREMRI and native MR images so generated may be combined, (or superimposed). (author)

  14. Pre-clinical functional magnetic resonance imaging. Pt. I. The kidney

    Energy Technology Data Exchange (ETDEWEB)

    Zoellner, Frank G.; Kalayciyan, Raffi; Chacon-Caldera, Jorge; Zimmer, Fabian; Schad, Lothar R. [Heidelberg Univ., Mannheim (Germany). Computer Assisted Clinical Medicine

    2014-07-01

    The prevalence of chronic kidney disease (CKD) is increasing worldwide. In Europe alone, at least 8% of the population currently has some degree of CKD. CKD is associated with serious comorbidity, reduced life expectancy, and high economic costs; hence, the early detection and adequate treatment of kidney disease is important. Pre-clinical research can not only give insights into the mechanisms of the various kidney diseases but it also allows for investigating the outcome of new drugs developed to treat kidney disease. Functional magnetic resonance imaging provides non-invasive access to tissue and organ function in animal models. Advantages over classical animal research approaches are numerous: the same animal might be repeatedly imaged to investigate a progress or a treatment of disease over time. This has also a direct impact on animal welfare and the refinement of classical animal experiments as the number of animals in the studies might be reduced. In this paper, we review current state of the art in functional magnetic resonance imaging with a focus on pre-clinical kidney imaging.

  15. Pre-clinical functional magnetic resonance imaging. Pt. I. The kidney

    International Nuclear Information System (INIS)

    Zoellner, Frank G.; Kalayciyan, Raffi; Chacon-Caldera, Jorge; Zimmer, Fabian; Schad, Lothar R.

    2014-01-01

    The prevalence of chronic kidney disease (CKD) is increasing worldwide. In Europe alone, at least 8% of the population currently has some degree of CKD. CKD is associated with serious comorbidity, reduced life expectancy, and high economic costs; hence, the early detection and adequate treatment of kidney disease is important. Pre-clinical research can not only give insights into the mechanisms of the various kidney diseases but it also allows for investigating the outcome of new drugs developed to treat kidney disease. Functional magnetic resonance imaging provides non-invasive access to tissue and organ function in animal models. Advantages over classical animal research approaches are numerous: the same animal might be repeatedly imaged to investigate a progress or a treatment of disease over time. This has also a direct impact on animal welfare and the refinement of classical animal experiments as the number of animals in the studies might be reduced. In this paper, we review current state of the art in functional magnetic resonance imaging with a focus on pre-clinical kidney imaging.

  16. Imaging vascular function for early stage clinical trials using dynamic contrast-enhanced magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Leach, M.O.; Orton, M. [Institute of Cancer Research and Royal Marsden NHS Foundation Trust, Cancer Research UK and EPSRC Cancer Imaging Centre, Sutton, Surrey (United Kingdom); Morgan, B. [Univ. of Leicester, College of Medicine, Biological Sciences and Psychology, Leicester (United Kingdom); Tofts, P.S. [Brighton and Sussex Medical School, Univ. of Sussex, Clinical Imaging Sciences Centre, Sussex (United Kingdom); Buckley, D.L. [University of Leeds, Division of Medical Physics, Leeds (United Kingdom); Huang, W. [Oregon Health and Science Univ., Advanced Imaging Research Centre, Portland, OR (United States); Horsfield, M.A. [Medical Physics Section, Leicester Royal Infirmary, Dept. of Cardiovascular Sciences, Leicester (United Kingdom); Chenevert, T.L. [Univ. of Michigan Health System, Ann Arbor, MI (United States); Collins, D.J. [Royal Marsden Hospital NHS Foundation Trust, Cancer Research UK and EPSRC Cancer Imaging Centre, Sutton, Surrey (United Kingdom); Jackson, A. [Univ. of Manchester, Wolfson Molecular Imaging Centre, Withington, Manchester, M20 3LJ (United Kingdom); Lomas, D. [Univ. of Cambridge, Dept. of Radiology, Cambridge (United Kingdom); Whitcher, B. [Unit 2 Greenways Business Park, Mango Solutions, Chippenham (United Kingdom); Clarke, L. [Cancer Imaging Program, Imaging Technology Development Branch, Rockville, MD (United States); Plummer, R. [Univ. of Newcastle Upon Tyne, The Medical School, Medical Oncology, Northern Inst. for Cancer Research, Newcastle Upon Tyne (United Kingdom); Judson, I. [Royal Marsden Hospital, Sutton, Surrey (United Kingdom); Jones, R. [Beatson West of Scotland Cancer Centre, Glasgow (United Kingdom); Alonzi, R. [Mount Vernon Cancer Centre, Northwood (United Kingdom); Brunner, T. [Gray Inst. for Radiation, Oncology and Biology, Oxford (United Kingdom); Koh, D.M. [Royal Marsden NHS Foundation Trust, Diagnostic Radiology, Sutton, Surrey (United Kingdom)] [and others

    2012-07-15

    Many therapeutic approaches to cancer affect the tumour vasculature, either indirectly or as a direct target. Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) has become an important means of investigating this action, both pre-clinically and in early stage clinical trials. For such trials, it is essential that the measurement process (i.e. image acquisition and analysis) can be performed effectively and with consistency among contributing centres. As the technique continues to develop in order to provide potential improvements in sensitivity and physiological relevance, there is considerable scope for between-centre variation in techniques. A workshop was convened by the Imaging Committee of the Experimental Cancer Medicine Centres (ECMC) to review the current status of DCE-MRI and to provide recommendations on how the technique can best be used for early stage trials. This review and the consequent recommendations are summarised here. (orig.)

  17. DIAGNOSTIC ACCURACY OF CLINICAL AND MAGNETIC RESONANCE IN KNEE MENISCI AND LIGAMENTOUS INJURIES

    Directory of Open Access Journals (Sweden)

    Nilesh

    2016-03-01

    Full Text Available OBJECTIVE The purpose of this study was to evaluate the reliability of clinical diagnosis compared to MRI findings in ligamentous and meniscal injuries with respect to arthroscopic confirmation as a gold standard. METHODS 485 patients with knee injuries were prospectively assessed by clinical evaluation and magnetic resonance imaging and correlated after therapeutic arthroscopy. The overall accuracy, clinically productive values of sensitivity and specificity was derived. The actual value of the test with respect to positive predictive and negative predictive value was also derived, taking arthroscopic findings as confirmatory. The overall partial and total agreement among the clinical, MRI and arthroscopy was documented. RESULTS The overall accuracy for clinical examination was 85, 92, 100 and 100 and accuracy for MRI was 90, 97, 97 and 97 for detecting medial meniscus, lateral meniscus, ACL and PCL tears respectively. Clinically lateral meniscus tears are difficult to diagnose clinically with negative predictive value (90 whereas ACL injuries do not need MRI for diagnosis as evident by a high negative predictive value (100 of clinical examination. Total agreement with the clinical findings confirmed by arthroscopy was 64.40% which was relatively high as compared to total agreement of MRI findings which was only 31.50%. We found similar total agreement versus total disagreement of both clinical and MRI to be only 2.74% indicating very high accuracy in clinical diagnosis of meniscal and ligamentous injuries combined. CONCLUSION The clinical evaluation alone is sufficient to diagnose meniscal and ACL/PCL pathologies and MRI should be considered only as a powerful negative diagnostic tool. The arthroscopy decision should not be heavily dependent on MRI for ligamentous injuries but reverse is true for meniscal lesions. MR evaluation functions as a powerful negative diagnostic tool to rule out doubtful and complex knee injuries.

  18. Relationship between clinical findings of temporomandibular disorders and magnetic resonance imaging

    International Nuclear Information System (INIS)

    Iizuka, Yasuyuki; Miura, Hiroyuki; Ishikawa, Fujiro; Kikuchi, Shiori; Konishi, Nobuhiro; Sakamaki, Kimio

    1996-01-01

    The present study was conducted to investigate the relationship between magnetic resonance imaging (MRI) of the temporomandibular joint (TMJ) and clinical findings of patients having symptoms of temporomandibular disorders, and to consider the possibility to grasp the internal derangement of the TMJ from clinical findings. Subjects were 80 patients who visited to ask orthodontic treatment 16 males and 64 females. The average age was 22 years and 4 months. We performed a investigation of both their previous and present illness. In addition, to decide the correct condition concerning the internal derangement of the TMJ, patients were given MRI examinations (G. E. medical system Signa 1.5 Tesla) before orthodontic treatment. Results were as follows: The three symptoms of temporomandibular disorders-noise, pain, and abnormal mandibular movement, were not related to constant disk displacement. It seemed difficult to infer and obtain the diagnosis of the condition of internal derangement of the TMJ only from clinical findings. In a dental clinics having no medical imaging instrument such as MRI, it was, however, considered that the following items will make it possible to define the condition of internal derangements of the TMJ from clinical findings. As to respects concerning clinical findings, it is necessary to consider the previous illness as well as present illness. TMJ noise indicates a higher relationship to the disk displacement in MRI findings. The temporomandibular joint with plural symptoms indicated a higher incidence of disk displacement examined by MR Imaging than that with a single symptom. (author)

  19. Magnetic resonance imaging of injuries to the ankle joint: can it predict clinical outcome?

    Science.gov (United States)

    Zanetti, M; De Simoni, C; Wetz, H H; Zollinger, H; Hodler, J

    1997-02-01

    To predict clinical outcome after ankle sprains on the basis of magnetic resonance (MR) findings. Twenty-nine consecutive patients (mean age 32.9 years, range 13-60 years) were examined clinically and with MR imaging both after trauma and following standardized conservative therapy. Various MR abnormalities were related to a clinical outcome score. There was a tendency for a better clinical outcome in partial, rather than complete, tears of the anterior talofibular ligament and when there was no fluid within the peroneal tendon sheath at the initial MR examination (P = 0.092 for either abnormality). A number of other MR features did not significantly influence clinical outcome, including the presence of a calcaneofibular ligament lesion and a bone bruise of the talar dome. Clinical outcome after ankle sprain cannot consistently be predicted by MR imaging, although MR imaging may be more accurate when the anterior talofibular ligament is only partially torn and there are no signs of injury to the peroneal tendon sheath.

  20. Dental magnetic resonance imaging

    International Nuclear Information System (INIS)

    Hilgenfeld, Tim; Bendszus, Martin; Haehnel, Stefan

    2016-01-01

    Growing distribution and utilization of digital volume tomography (DVT) extend the spectrum of clinical dental imaging. Additional diagnostic value, however, comes along with an increasing amount of radiation. In contrast, magnetic resonance imaging is a radiation free imaging technique. Furthermore, it offers a high soft tissue contrast. Morphological and numerical dental anomalies, differentiation of periapical lesions and exclusion of complications of dental diseases are field of applications for dental MRI. In addition, detection of caries and periodontal lesions and injury of inferior alveolar nerve are promising application areas in the future.

  1. Magnetic resonance imaging in the evaluation of clinical treatment of otospongiosis: a pilot study.

    Science.gov (United States)

    de Oliveira Vicente, Andy; Chandrasekhar, Sujana S; Yamashita, Helio K; Cruz, Oswaldo Laercio M; Barros, Flavia A; Penido, Norma O

    2015-06-01

    To evaluate the applicability of magnetic resonance imaging (MRI) as a method for monitoring the activity of otospongiotic lesions before and after clinical treatment. Prospective, randomized, controlled, double-blind study. One single tertiary care institution in a large, cosmopolitan city. Twenty-six patients (n = 42 ears) with clinical, audiometric, and tomographic diagnosis of otosclerosis were enrolled. If computed tomography (CT) demonstrated active lesions, these patients underwent MRI to detect otospongiotic foci, seen as areas of gadolinium enhancement. Patients were divided into 3 groups and received treatment with placebo, sodium alendronate, or sodium fluoride for 6 months. After this period, clinical and audiometric evaluations and a second MRI were performed. Each MRI was evaluated by both a neuroradiologist and an otolaryngologist in a subjective (visual) and objective (using specific eFilm Workstation software) manner. Otospongiosis was most predominantly identified in the region anterior to the oval window, and this site was reliable for comparing pre- and posttreatment scans. The patients in the alendronate and sodium fluoride groups had MRI findings that suggested a decrease in activity of otospongiotic lesions, more relevant in the alendronate group. These findings were statistically significant for both subjective and objective MRI evaluations. MRI shows higher sensitivity than clinical or audiometric assessment for detecting reduction in activity of otospongiosis. The objective MRI evaluation based on software analysis was the most accurate method of monitoring clinical treatment response in otospongiosis. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2015.

  2. Contrast-enhanced magnetic resonance imaging of tumours of the central nervous systems: a clinical review

    International Nuclear Information System (INIS)

    Graif, M.; Steiner, R.E.

    1986-01-01

    The clinical application of the intravascular paramagnetic contrast agent gadolinium-DTPA for magnetic resonance imaging (MRI) imaging of tumours of the central nervous system (CNS) has been assessed over the past 3 years. Various patterns of contrast enhancement were observed, and situations in MRI where the administration of contrast medium may be useful have been defined. These include lesions which are isointense with normal brain matter, the separation of tumour from surrounding oedema, evaluation of the degree of blood-brain barrier breakdown, delineation of tumours obscured by overlying calcification on computed tomography (CT) and in the investigation of lesions in anatomical areas where CT has known limitations (brain, stem, cervical spine). Changes in relaxation times in normal and abnormal tissues following contrast medium, toxicity and dosage of gadolinium-DTPA, and MRI pulse sequence techniques are reviewed. (author)

  3. Clinical impacts of 3.0 Tesla magnetic resonance imaging in stroke patients

    International Nuclear Information System (INIS)

    Inoue, Takashi; Ogasawara, Kuniaki; Ogawa, Akira

    2004-01-01

    The progress of the magnetic resonance (MR) imaging in the cerebral stroke patients was remarkable, and it became possible to evaluate a brain perfusion or function. Here, we describe about the clinical application of the neuronal tracts and brain perfusion evaluation using 3.0 Tesla MR imaging. The subjects were patients with internal cerebral hemorrhage and major cerebral occlusive diseases. Three dimensional anisotropy contrast (3DAC) imaging and diffusion tensor imaging (DTI) were accepted to estimate the damages of neurnal tracts. Perfusion weighted images with the contrast medium were performed for a quantitative evaluation. The pyramidal tracts were depicted well with 3DAC imaging. Fractional anisotropy (FA) value generated from DTI can predict the outcome of the motor dysfunction in each patient at early stage. Cerebral blood volume calculated from perfusion weighted imaging (PWI) was correlated with and cerebral vascular reserve capacity. 3.0 Tesla MR imaging may develop in cerebral stroke patients in near future. (author)

  4. Magnetic resonance imaging of a cerebral cavernous haemangioma in a dog : clinical communication

    Directory of Open Access Journals (Sweden)

    J.P. Schoeman

    2002-07-01

    Full Text Available A 13-month-old, neutered, male Golden retriever presented with seizures and progressive depression. Clinical and neurological assessment was consistent with severe intracranial disease. The neurological condition progressively deteriorated and magnetic resonance imaging (MRI revealed the presence of a large, contrast-enhancing, space-occupying mass in the right cerebral hemisphere. Therapy with corticosteroids, mannitol and furosemide ameliorated the signs of depression and ataxia, but the owner elected euthanasia after 1 week. Post mortem examination of the brain confirmed the presence of a large haemorrhagic lesion in the right olfactory lobe, the histopathological appearance of which was consistent with cerebral cavernous haemangioma. This is the 1st case describing the MRI appearance of a cavernous haemangioma of the cerebrum in the veterinary literature.

  5. In vivo neurochemistry with emission tomography and magnetic resonance spectroscopy: clinical applications

    International Nuclear Information System (INIS)

    Sole, Angelo Del; Gambini, Anna; Falini, Andrea; Lecchi, Michela; Lucignani, Giovanni

    2002-01-01

    The assessment of neurochemical processes in vivo has received much attention in the past decade as techniques such as positron or single photon emission tomography (PET and SPET), and magnetic resonance spectroscopy (MRS) have become more available. With PET and SPET, basic processes, such as blood flow and oxygen or glucose metabolism, can be regionally assessed, along with more specific functions such as the production, release, and reuptake of neurotransmitters and their occupancy of specific receptors. At the same time, MRS can reveal changes in concentration of several hydrogenate compounds in the brain. All these methods have been extensively applied for research in neurology, and some applications have reached the clinical level, namely for the study of degenerative diseases, motor-neuron diseases, movement disorders, cerebrovascular diseases, and epilepsy. This article focuses on the most relevant information that can be obtained with these complementary techniques to help clinicians in the assessment of neurological diseases. (orig.)

  6. In vivo neurochemistry with emission tomography and magnetic resonance spectroscopy: clinical applications

    Energy Technology Data Exchange (ETDEWEB)

    Sole, Angelo Del [Azienda Ospedaliera San Paolo e Universita di Milano, 20142 Milan (Italy); Gambini, Anna; Falini, Andrea [IRCCS H San Raffaele e Universita Vita e Salute, 20132 Milan (Italy); Lecchi, Michela [Azienda Ospedaliera L. Sacco e Universita di Milano, 20157 Milan (Italy); Lucignani, Giovanni [Azienda Ospedaliera L. Sacco e Universita di Milano, 20157 Milan (Italy); Universita di Milano, Istituto di Scienze Radiologiche, Cattedra di Medicina Nucleare c/o Ospedale L. Sacco, Via G.B. Grassi, 74, 20157 Milan (Italy)

    2002-10-01

    The assessment of neurochemical processes in vivo has received much attention in the past decade as techniques such as positron or single photon emission tomography (PET and SPET), and magnetic resonance spectroscopy (MRS) have become more available. With PET and SPET, basic processes, such as blood flow and oxygen or glucose metabolism, can be regionally assessed, along with more specific functions such as the production, release, and reuptake of neurotransmitters and their occupancy of specific receptors. At the same time, MRS can reveal changes in concentration of several hydrogenate compounds in the brain. All these methods have been extensively applied for research in neurology, and some applications have reached the clinical level, namely for the study of degenerative diseases, motor-neuron diseases, movement disorders, cerebrovascular diseases, and epilepsy. This article focuses on the most relevant information that can be obtained with these complementary techniques to help clinicians in the assessment of neurological diseases. (orig.)

  7. Cardiac magnetic resonance imaging

    African Journals Online (AJOL)

    2011-03-06

    Mar 6, 2011 ... Cardiac magnetic resonance imaging. Cardiovascular magnetic resonance imaging is becoming a routine diagnostic technique. BRUCE s sPOTTiswOOdE, PhD. MRC/UCT Medical Imaging Research Unit, University of Cape Town, and Division of Radiology, Stellenbosch University. Bruce Spottiswoode ...

  8. Investigation of Factors Affecting Body Temperature Changes During Routine Clinical Head Magnetic Resonance Imaging

    Science.gov (United States)

    Kim, Myeong Seong

    2016-01-01

    Background Pulsed radiofrequency (RF) magnetic fields, required to produce magnetic resonance imaging (MRI) signals from tissue during the MRI procedure have been shown to heat tissues. Objectives To investigate the relationship between body temperature rise and the RF power deposited during routine clinical MRI procedures, and to determine the correlation between this effect and the body’s physiological response. Patients and Methods We investigated 69 patients from the Korean national cancer center to identify the main factors that contribute to an increase in body temperature (external factors and the body’s response) during a clinical brain MRI. A routine protocol sequence of MRI scans (1.5 T and 3.0 T) was performed. The patient’s tympanic temperature was recorded before and immediately after the MRI procedure and compared with changes in variables related to the body’s physiological response to heat. Results Our investigation of the physiological response to RF heating indicated a link between increasing age and body temperature. A higher increase in body temperature was observed in older patients after a 3.0-T MRI (r = 0.07, P = 0.29 for 1.5-T MRI; r = 0.45, P = 0.002 for 3.0-T MRI). The relationship between age and body heat was related to the heart rate (HR) and changes in HR during the MRI procedure; a higher RF power combined with a reduction in HR resulted in an increase in body temperature. Conclusion A higher magnetic field strength and a decrease in the HR resulted in an increase in body temperature during the MRI procedure. PMID:27895872

  9. Magnetic resonance imaging the basics

    CERN Document Server

    Constantinides, Christakis

    2014-01-01

    Magnetic resonance imaging (MRI) is a rapidly developing field in basic applied science and clinical practice. Research efforts in this area have already been recognized with five Nobel prizes awarded to seven Nobel laureates in the past 70 years. Based on courses taught at The Johns Hopkins University, Magnetic Resonance Imaging: The Basics provides a solid introduction to this powerful technology. The book begins with a general description of the phenomenon of magnetic resonance and a brief summary of Fourier transformations in two dimensions. It examines the fundamental principles of physics for nuclear magnetic resonance (NMR) signal formation and image construction and provides a detailed explanation of the mathematical formulation of MRI. Numerous image quantitative indices are discussed, including (among others) signal, noise, signal-to-noise, contrast, and resolution. The second part of the book examines the hardware and electronics of an MRI scanner and the typical measurements and simulations of m...

  10. Clinical significance of dynamic magnetic resonance imaging in the evaluation of wrist joint in Rheumatoid arthritis

    International Nuclear Information System (INIS)

    Shim, Yong Woon; Suh, Jin Suck; Lee, Soo Kon; Lee, Ji Soo; Cho, Jae Hyun

    1996-01-01

    To assess the role of contrast-enhanced dynamic Magnetic Resonance Imaging in evaluation disease activity of rheumatoid arthritis. Forty-seven wrist joints with rheumatoid arthritis were examined prospectively. Coronal images of the wrist were obtained using fat-suppression Fast multi-planar spoiled gradient recalled (FMPSPGR) acquisition in the steady state ; TR/TE 102/6.4 msec, flip angle = 60, 4 slices per sequence, FOV = 8 cm, matrix 256 X 192 at 1.5 Tesla. Scans were carried out once before and five to eight times after an intravenous Gd-DPTA injection, at 30-second-intervals. The enhancement of synovium were measured, the enhancement ratio was calculated(postcontrast SNR/precontrast SNR) and time-enhancement ratio curves were plotted. Patients were divided into three groups according to the ratio of initial to peak enhancement : less than 30% ; 30-80% more than 80%. Differences among the three groups were statistically tested using clinical indices and laboratory data as variable. Comparing one group with another, there were no significant differences in clinical indices and laboratory data except for the parameter of grip strength. Enhancement pattern measured in a single wrist joint was not comparable to a clinical index in predicting disease activity in rheumatoid arthritis

  11. Delayed-enhancement magnetic resonance imaging in patients with clinically suspected stress cardiomyopathy (Tako-Tsubo)

    International Nuclear Information System (INIS)

    Muellerleile, K.; Sultan, A.; Willems, S.; Lund, G.; Groth, M.; Adam, G.; Barmeyer, A.; Meinertz, T.; Koester, R.; Heitzer, T.

    2010-01-01

    To compare the ability of delayed-enhancement magnetic resonance imaging (DE-MRI) and other MRI and clinical parameters to identify diseases mimicking stress cardiomyopathy (SCM). The study included 14 consecutive patients fulfilling the American Heart Association (AHA) criteria for SCM with acute left ventricular dysfunction in the absence of coronary artery disease, triggered by psychological stress. The MRI protocol consisted of cine, T 2-weighted, first-pass-perfusion (FPP) and DE-MRI. Six patients with DE were classified as mimicking SCM (non-SCM) and 8 patients without DE as SCM. FPP defects were found in 4 patients with non-SCM and in none with SCM (p < 0.05). Myocardial edema was found in 5 patients with non-SCM and in 2 patients with SCM (p = ns). No significant differences in clinical findings such as ECG, cardiac markers and echocardiographic recovery of left ventricular function were found between patients with non-SCM and SCM. Non-SCM defined by DE-MRI is a frequent finding in patients fulfilling the AHA criteria for SCM. Clinical findings seem to be of limited value to differentiate between non-SCM and SCM. (orig.)

  12. Clinical perspectives of hybrid proton-fluorine magnetic resonance imaging and spectroscopy.

    Science.gov (United States)

    Wolters, Martijn; Mohades, Seyede G; Hackeng, Tilman M; Post, Mark J; Kooi, Marianne E; Backes, Walter H

    2013-05-01

    The number of applications of fluorine 19 (19F) magnetic resonance (MR) imaging and spectroscopy in biomedical and clinical research is steadily growing. The 100% natural abundance of fluorine and its relatively high sensitivity for MR (83% to that of protons) make it an interesting nucleus for a wide range of MR applications. Fluorinated contrast media have a number of advantages over the conventionally used gadolinium-based or iron-based contrast agents. The absence of an endogenous fluorine background intensity in the human body facilitates reliable quantification of fluorinated contrast medium or drugs. Anatomy can be visualized separately with proton MR imaging, creating the application of hybrid hydrogen 1 (1H)/19F MR imaging. The availability of 2 channels (ie, the 1H and 19F channels) enables dual-targeted molecular imaging. Recently, novel developments have emerged on fluorine-based contrast media in preclinical studies and imaging techniques. The developments in fluorine MR seem promising for clinical applications, with contributions in therapy monitoring, assessment of lung function, angiography, and molecular imaging. This review outlines the translation from recent advances in preclinical MR imaging and spectroscopy to future perspectives of clinical hybrid 1H/19/F MR imaging applications.

  13. Clinical examination and magnetic resonance imaging in the assessment of ankle sprains treated with an orthosis.

    Science.gov (United States)

    De Simoni, C; Wetz, H H; Zanetti, M; Hodler, J; Jacob, H; Zollinger, H

    1996-03-01

    This is a prospective clinical study of treatment of ankle sprains with an ankle brace that permits ankle dorsiflexion and plantarflexion of 20 degrees, but limits inversion and eversion for 6 weeks. The ankle brace is followed by physiotherapy for another 6 weeks. Thirty patients were evaluated with clinical examination and magnetic resonance (MR) imaging before treatment and after 12 weeks of treatment. MR imaging revealed acute tears in the anterior talofibular ligament in all 30 ankles (100%) and tears in the calcaneofibular ligament in 25 of 30 ankles (83%). At 12 weeks after injury, MR evidence of healing was present for the anterior talofibular ligament in 22 of 30 ankles (73%) and for the calcaneofibular ligament in 23 of 25 ankles (92%). Postural sway analysis after therapy was used to quantify functional stability of the ankle. There was no correlation with MR findings, but there was a correlation with the subjective impression of functional instability. Twenty-eight of 30 patients (93%) had a functionally stable ankle after 12 weeks of treatment. MR findings after ankle sprain could not predict clinical outcome.

  14. Magnetic Resonance Force Microscopy System

    Data.gov (United States)

    Federal Laboratory Consortium — The Magnetic Resonance Force Microscopy (MRFM) system, developed by ARL, is the world's most sensitive nuclear magnetic resonance (NMR) spectroscopic analysis tool,...

  15. Nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Ethier, R.; Melanson, D.; Peters, T.M.

    1983-01-01

    Ten years following computerized tomography, a new technique called nuclear magnetic resonance revolutionizes the field of diagnostic imaging. A major advantage of nuclear magnetic resonance is that the danger of radiation is non-existent as compared to computerized tomography. When parts of the human body are subject to radio-frequencies while in a fixed magnetic field, its most detailed structures are revealed. The quality of images, the applications, as well as the indications are forever increasing. Images obtained at the level of the brain and spinal cord through nuclear magnetic resonance supercede those obtained through computerized tomography. Hence, it is most likely that myelography, along with pneumoencephalography will be eliminated as a diagnostic means. It is without a doubt that nuclear magnetic resonance is tomorrow's computerized tomography [fr

  16. The diagnosis of silicone breast-implant rupture: clinical findings compared with findings at magnetic resonance imaging

    DEFF Research Database (Denmark)

    Hölmich, Lisbet Rosenkrantz; Fryzek, Jon P; Kjøller, Kim

    2005-01-01

    The objective was to evaluate the usefulness of clinical examination in the evaluation of breast-implant integrity, using the diagnosis at magnetic resonance imaging (MRI) as the "gold standard." Fifty-five women with 109 implants underwent a breast examination either just before or shortly after...

  17. Clinical use of gadobutrol for contrast-enhanced magnetic resonance imaging of neurological diseases

    Directory of Open Access Journals (Sweden)

    Cheng KT

    2012-02-01

    Full Text Available Kenneth T Cheng1, Hannah Y Cheng2, Kam Leung31Department of Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, MD, USA; 2Freelance Technical Writer, New Orleans, LA, USA; 3National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD, USAAbstract: Contrast-enhanced magnetic resonance imaging (CE-MRI is an important clinical tool for diagnosing neurological diseases. The appropriate use of a suitable MRI contrast agent or contrast pharmaceutical is essential for CE-MRI to produce desirable diagnostic images. Currently, there are seven contrast agents (CAs or pharmaceuticals approved for clinical imaging of the central nervous system (CNS in the US, Europe, or Japan. All of the clinically approved CAs are water-soluble gadolinium-based contrast agents (GBCAs which do not penetrate the CNS blood–brain barrier (BBB. These agents are used for imaging CNS areas without a BBB, or various pathologies, such as tumors and infection that break down the BBB and allow CAs to enter into the surrounding parenchyma. Clinically, GBCAs are most useful for detecting primary and secondary cerebral neoplastic lesions. Among these CNS GBCAs, gadobutrol (Gd-BT-DO3A, Gadovist™ is a neutral, nonionic, macrocyclic compound that showed promising results from clinical trials of CNS imaging. In comparison with other GBCAs, Gd-BT-DO3A has relatively high in vitro kinetic stability and r1 relaxivity. Gd-BT-DO3A has been recently approved by the US Food and Drug Administration (FDA in 2011 for CNS imaging. A review of available literature shows that Gd-BT-DO3A exhibits similar safety and clinical efficacy profiles to other GBCAs. Gd-BT-DO3A has the distinguishing feature that it is the only clinical agent commercially available in a formulation of 1.0 M concentration with a relatively higher in vitro T1 shortening per unit volume than other clinical GBCAs which are only

  18. Incidental extracerebral findings on brain nonenhanced magnetic resonance imaging: frequency, nondetection rate, and clinical importance

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ming-Liang; Wei, Xiao-Er [School of Medicine, Department of Radiology, Shanghai Jiao Tong University Affiliated Sixth People' s Hospital, Shanghai (China); Lu, Li-Yan [Nanjing Medical University, Department of Radiology, Nanjing First Hospital, Nanjing (China); Li, Wen-Bin [School of Medicine, Department of Radiology, Shanghai Jiao Tong University Affiliated Sixth People' s Hospital, Shanghai (China); Kashgar Prefecture Second People' s Hospital, Imaging Center, Kashgar (China)

    2017-03-15

    This study aims to elucidate the frequency, nondetection rate, and clinical importance of incidental extracerebral findings (IECFs) on brain nonenhanced magnetic resonance imaging (MRI). A total of 8284 brain MRIs performed between January 1, 2015 and December 31, 2015 were evaluated for the presence of IECFs and the distribution of IECFs was analyzed. IECFs were categorized as E1 (clinically unimportant, e.g., sinus mucosal thickening); E2 (likely unimportant, e.g., pharyngeal mucosal symmetrical thickening); and E3 (potentially important, e.g., pharyngeal mucosal asymmetrical thickening). The nondetection rate was determined by comparing the results of the structured approach with the initial MRI reports. The medical records were examined for patients with E3 IECFs to assess clinical importance and outcome of these lesions. A total of 5992 IECFs were found in 4469 of the 8284 patients (54.0%). E1 findings constituted 82.2% (4924/5992) of all IECFs; E2 constituted 16.6% (995/5992) and E3 constituted 1.2% (73/5992). Overall IECFs and E1 findings were significantly more common in male patients (P < 0.05). Statistically significant difference was also seen between the different age groups (P < 0.001). The nondetection rate was 56.9% (3409/5992) for overall IECFs and 32.9% (24/73) for E3 IECFs. Of the 73 patients with E3 IECFs, 34 (46.6%) received final diagnosis and appropriate treatment during the study period. IECFs are prevalent in clinical patients on brain MR images with a nondetection rate of 32.9% for potentially important (E3) findings. The reporting of IECFs according to clinical importance is helpful for patients' management. (orig.)

  19. T2 Magnetic Resonance Assay: Overview of Available Data and Clinical Implications

    Directory of Open Access Journals (Sweden)

    Ioannis M. Zacharioudakis

    2018-04-01

    Full Text Available Invasive candidiasis is a common healthcare-associated infection with a high mortality rate that can exceed 60% in cases of septic shock. Blood culture performance is far from ideal, due to the long time to positivity and suppression by antifungal agents. The T2 Magnetic Resonance (T2MR assay is an FDA-approved qualitative molecular diagnostic method that can detect and speciate the 5 most common Candida spp.; namely, Candida albicans, Candida glabrata, Candida parapsilosis, Candida tropicalis, and Candida krusei, in approximately 5 h. In a multicenter clinical trial that included both a prospective and a contrived arm to represent the full range of clinically relevant concentrations of Candida spp., T2MR demonstrated a sensitivity and specificity of 91.1% and 98.1%, respectively. The utility of T2MR in candidemia depends on the prevalence of disease in each clinical setting. In intensive care units and other high-prevalence settings, the incorporation of T2MR in diagnostic algorithms is very appealing. T2MR is expected to allow timely initiation of antifungal therapy and help with anti-fungal stewardship. In low-prevalence settings, the positive predictive value of T2MR might not be enough to justify initiation of antifungal treatment in itself. The performance of T2MR has not been studied in cases of deep-seated candidiasis. Despite some promising evidence in published clinical trials, further studies are needed to determine the performance of T2MR in invasive candidiasis without candidemia. Overall, experience with T2MR in everyday clinical practice is evolving but, in the right setting, this technology is expected to provide “actionable information” for the management of patients evaluated for candidemia.

  20. Magnetic Resonance Imaging of Patients With Chronic Lateral Epicondylitis: Is There a Relationship Between Magnetic Resonance Imaging Abnormalities of the Common Extensor Tendon and the Patient's Clinical Symptom?

    Science.gov (United States)

    Qi, Liang; Zhang, Yu-Dong; Yu, Rong-Bin; Shi, Hai-Bin

    2016-02-01

    The aim of the study is to determine the inter-reliability and intra-observer reliability of magnetic resonance imaging (MRI) for lateral epicondylitis and investigate whether there is a potential relationship between MRI abnormalities of the common extensor tendon (CET) and its clinical symptom.The study group comprised 96 consecutive patients (46 men and 50 women) with a clinical diagnosis of chronic lateral epicondylitis, which were examined on 3.0 T MR. An MRI scoring system was used to grade the degree of tendinopahty. Three independent musculoskeletal radiologists, who were blinded to the patients' clinical information, scored images separately. Clinical symptoms were assessed using the Patient-Rated Tennis Elbow Evaluation (PRTEE).Of all the patients, total 96 elbows had MRI-assessed tendinopathy, including 38 (39.6%) with grade 1, 31 (32.3%) with grade 2, and 27 (28.1%) with grade 3. Inter-observer reliability and intra-observer agreement for MRI interpretation of the grades of tendinopathy was good, and a positive correlation between the grades of tendinopathy and PRTEE was determined.MRI is a reliable tool in determining radiological severity of chronical lateral epicondylitis. The severity of MR signal changes positively correlate with the patient's clinical symptom.

  1. Clinical, laboratory, psychiatric and magnetic resonance findings in patients with Sydenham chorea

    International Nuclear Information System (INIS)

    Faustino, Patricia C.; Terreri, Maria Teresa R.A.; Rocha, Antonio J. da; Zappitelli, Marcelo C.; Lederman, Henrique M.; Hilario, Maria Odete E.

    2003-01-01

    The objective of this study was to determine the clinical and laboratory characteristics, psychiatric manifestations and magnetic resonance imaging (MRI) findings in children and adolescents with Sydenham chorea (SyC). The imaging examination was repeated 1 year after the acute phase of SyC. There were 19 patients with a mean age of 11.7 years and a predominance of females (79%);68% had generalized chorea and 53% moderate chorea. SyC presented as an isolated manifestation in 74%. No association between SyC and obsessive-compulsive disorder was found. Mental health problems were present in 45% of the patients. MRI analysis revealed persistent alterations in the caudate nucleus in three patients (16%), who presented recurrent episodes of chorea during the study. In one patient, MRI revealed the presence of nodular heteropathy close to the caudate nucleus region. We conclude that attention problems can be associated with acute clinical features of SyC and persistent alterations in the basal nuclei, evidenced by MRI, can be found in some patients who tend to suffer prolonged attacks and a greater number of recurrences. (orig.)

  2. Whole-body magnetic resonance angiography of patients using a standard clinical scanner

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, Tomas; Wikstroem, Johan; Eriksson, Mats-Ola; Lundberg, Anders; Ahlstroem, Haakan [Uppsala University Hospital, Department of Diagnostic Radiology, Uppsala (Sweden); Johansson, Lars [Uppsala University Hospital, Uppsala (Sweden); Ljungman, Christer [Uppsala University Hospital, Department of Vascular Surgery, Uppsala (Sweden); Hoogeven, Romhild [Philips Medical Systems, MR Clinical Science, Best (Netherlands)

    2006-01-01

    The purpose of this study was to evaluate the technique of whole-body magnetic resonance angiography (MRA) of patients with a standard clinical scanner. Thirty-three patients referred for stenoses, occlusions, aneurysms, assessment of patency of vascular grafts, vasculitis and vascular aplasia were examined in a 1.5-T scanner using its standard body coil. Three-dimensional sequences were acquired in four stations after administration of one intravenous injection of 40 ml conventional gadolinium contrast agent. Different vessel segments were evaluated as either diagnostic or nondiagnostic and regarding the presence of stenoses with more than 50% diameter reduction, occlusions or aneurysms. Of 923 vessel segments, 67 were not evaluable because of poor contrast filling (n=31), motion artefacts (n=20), venous overlap (n=12) and other reasons (n=4). Stenoses of more than 50%, occlusions or aneurysms were observed in 26 patients (129 segments). In nine patients additional unsuspected pathology was found. In 10 out of 14 patients (71/79 segments) there was conformity between MRA and digital subtraction angiography regarding the grade of stenosis. This study shows that whole-body MRA with a standard clinical scanner is feasible. Motion artefacts and the timing of the contrast agent through the different segments are still problems to be solved. (orig.)

  3. Nuclear magnetic resonance based metabolomics and liver diseases: Recent advances and future clinical applications.

    Science.gov (United States)

    Amathieu, Roland; Triba, Mohamed Nawfal; Goossens, Corentine; Bouchemal, Nadia; Nahon, Pierre; Savarin, Philippe; Le Moyec, Laurence

    2016-01-07

    Metabolomics is defined as the quantitative measurement of the dynamic multiparametric metabolic response of living systems to pathophysiological stimuli or genetic modification. It is an "omics" technique that is situated downstream of genomics, transcriptomics and proteomics. Metabolomics is recognized as a promising technique in the field of systems biology for the evaluation of global metabolic changes. During the last decade, metabolomics approaches have become widely used in the study of liver diseases for the detection of early biomarkers and altered metabolic pathways. It is a powerful technique to improve our pathophysiological knowledge of various liver diseases. It can be a useful tool to help clinicians in the diagnostic process especially to distinguish malignant and non-malignant liver disease as well as to determine the etiology or severity of the liver disease. It can also assess therapeutic response or predict drug induced liver injury. Nevertheless, the usefulness of metabolomics is often not understood by clinicians, especially the concept of metabolomics profiling or fingerprinting. In the present work, after a concise description of the different techniques and processes used in metabolomics, we will review the main research on this subject by focusing specifically on in vitro proton nuclear magnetic resonance spectroscopy based metabolomics approaches in human studies. We will first consider the clinical point of view enlighten physicians on this new approach and emphasis its future use in clinical "routine".

  4. Magnetic resonance angiography of peripheral arteries of the hand and its clinical usefulness

    International Nuclear Information System (INIS)

    Arikawa, Kouzou

    1996-01-01

    We established requirements for display of peripheral arteries and veins of the hand on magnetic resonance angiography (MRA) in normal adults. We performed MRA in 20 normal adult volunteers and 3 patients using the same method and parameters and obtained useful clinical examinations. Few studies have evaluated the use of MRA in the hand, especially for peripheral arteries and veins, because of problems of vessel diameter, velocity blood flow, and computer memory capacity. The diagnostic accuracy of MRA is largely dependent on the MR equipment, MR technique, ray-tracing technique, film reading system, and the skill of the MRA film reader. Because MRA methods are not standardized, optimal methods must be determined that produce the accurate information needed for diagnosis of disease. In 20 normal adults, the following MRA parameters allowed us to consistently visualize the peripheral arteries and veins: flip angle, 90deg; TR, 35; TE, 16; slice thickness, 2 mm; FOV, 170; NSA, 2; acquisition matrix, 141 x 256; and room temperature, 22degC. We were able to obtain clear MRA images by the multiple slide slice method, which corrects a weakness of usual methods of display. Results of MRA examinations with our methods and parameters in 20 normal adult volunteers and 3 patients suggest that MRA is safe and useful for clinical examination of the hand. (author)

  5. Diagnosis of deep endometriosis: clinical examination, ultrasonography, magnetic resonance imaging, and other techniques.

    Science.gov (United States)

    Bazot, Marc; Daraï, Emile

    2017-12-01

    The aim of the present review was to evaluate the contribution of clinical examination and imaging techniques, mainly transvaginal sonography and magnetic resonance imaging (MRI) to diagnose deep infiltrating (DE) locations using prisma statement recommendations. Clinical examination has a relative low sensitivity and specificity to diagnose DE. Independently of DE locations, for all transvaginal sonography techniques a pooled sensitivity and specificity of 79% and 94% are observed approaching criteria for a triage test. Whatever the protocol and MRI devices, the pooled sensitivity and specificity for pelvic endometriosis diagnosis were 94% and 77%, respectively. For rectosigmoid endometriosis, pooled sensitivity and specificity of MRI were 92% and 96%, respectively fulfilling criteria of replacement test. In conclusion, advances in imaging techniques offer high sensitivity and specificity to diagnose DE with at least triage value and for rectosigmoid endometriosis replacement value imposing a revision of the concept of laparoscopy as the gold standard. Copyright © 2017 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  6. The clinical utility of nuclear magnetic resonance spectroscopy: recent in vitro, in vivo animal and clinical observations

    International Nuclear Information System (INIS)

    Blackstock, A. William; Kwock, Lester; Mukherji, Suresh K.; Schiro, Sharon; Tepper, Joel E.

    1995-01-01

    Purpose/Objective: Combined radiation and 5-fluorouracil (5-FU) has resulted in improved outcomes in patients treated with gastrointestinal malignancies and squamous cancers of the head and neck. In our first aim, we proposed that the enhanced cell kill and tumor regression observed with the combination of 5-FU and radiation is related to radiation potentiating the anti-tumor effects of 5-FU. Using fluorine-19 ( 19 F) nuclear magnetic resonance (nmr) we non-invasively determined the tumor clearance rates of 5-FU +/- radiation in an animal model and used this research tool to predict tumor response in patients receiving concurrent radiation and 5-FU therapy. Our second aim was to evaluate the use of proton ( 1 H) nmr spectroscopy to non-invasively determine the spectral characteristics of malignant tumors in the head and neck and liver and correlate these clinical observations with in vitro and in vivo data. Materials and Methods: 1 H and 19 F spectroscopic analysis were performed with a 2.0T Otsuka magnetic resonance imaging and spectroscopy system. 1 H nmr patient studies were done on a clinical 1.5T Philips MR system. In vitro magnetic resonance spectroscopy (MRS) studies were performed on a 11 T Bruker nmr system. Animal experiments for the 19 F nmr studies were performed on 3-6 week old female (Nu/Nu) athymic nude mice. Animals were injected s.c. with 10 6 human colon adenocarcinoma (HT-29) cells. At a tumor size of 1.0 cm, animals in the first group received i.v. 5-FU (100 mg/kg) immediately prior to spectroscopic analysis. Animals in the second group were treated with a single radiation dose of either 2 Gy or 10 Gy just prior to the 5-FU injection and subsequent spectroscopy. Spectroscopic analyses were performed at 20-30 minute intervals for 4-6 hr's. Results: 19 F nmr: A decrease in tumor clearance was observed in tumors pre-treated with a single dose of irradiation (2.0 Gy and 10 Gy). The clearance rate of the 5-FU for non-irradiated animals was 0.0178 min

  7. Magnetic Resonance (MR) Defecography

    Science.gov (United States)

    ... to a CD or uploaded to a digital cloud server. Magnetic resonance (MR) defecography is a special ... with you. top of page What are the benefits vs. risks? Benefits MR defecography helps assess pelvic ...

  8. Magnetic resonance angiography (MRA)

    International Nuclear Information System (INIS)

    Arlart, I.P.; Guhl, L.

    1992-01-01

    An account is given in this paper of the physical and technical principles underlying the 'time-of-flight' technique for imaging of vessels by magnetic resonance tomography. Major indications for the new procedure of magnetic resonance angiography at present are intracerebral and extracerebral vessels, with digital subtraction angiography quite often being required to cope with minor alterations (small aneurysms, small occlusions). Magnetic resonance angiography and digital subtraction angiography are compared to each other for advantages and disadvantages. Basically, replacement of radiological angiography by magnetic resonance angiography appears to be possible only within limits, since X-ray diagnostics primarily provides morphological information about vessels, whereas flow dynamics is visualized by the 'time-of-flight' technique. (orig.) [de

  9. Magnetic Resonance Cholangiopancreatography (MRCP)

    Science.gov (United States)

    ... radio waves and a computer to evaluate the liver, gallbladder, bile ducts, pancreas and pancreatic duct for disease. It is ... of the hepatobiliary and pancreatic systems, including the liver, gallbladder, bile ducts, pancreas and pancreatic duct . Magnetic resonance imaging (MRI) ...

  10. Magnetic Resonance Sensors

    Directory of Open Access Journals (Sweden)

    Robert H. Morris

    2014-11-01

    Full Text Available Magnetic Resonance finds countless applications, from spectroscopy to imaging, routinely in almost all research and medical institutions across the globe. It is also becoming more frequently used for specific applications in which the whole instrument and system is designed for a dedicated application. With beginnings in borehole logging for the petro-chemical industry Magnetic Resonance sensors have been applied to fields as varied as online process monitoring for food manufacture and medical point of care diagnostics. This great diversity is seeing exciting developments in magnetic resonance sensing technology published in application specific journals where they are often not seen by the wider sensor community. It is clear that there is enormous interest in magnetic resonance sensors which represents a significant growth area. The aim of this special edition of Sensors was to address the wide distribution of relevant articles by providing a forum to disseminate cutting edge research in this field in a single open source publication.[...

  11. Magnetic resonance angiography

    Science.gov (United States)

    ... Saunders; 2015:chap 17. Litt H, Carpenter JP. Magnetic resonance imaging. In: Cronenwett JL, Johnston KW, eds. Rutherford's Vascular Surgery . 8th ed. Philadelphia, PA: Elsevier Saunders; 2014:chap ...

  12. Nuclear magnetic resonance gyroscope

    International Nuclear Information System (INIS)

    Grover, B.C.

    1984-01-01

    A nuclear magnetic resonance gyro using two nuclear magnetic resonance gases, preferably xenon 129 and xenon 131, together with two alkaline metal vapors, preferably rubidium, potassium or cesium, one of the two alkaline metal vapors being pumped by light which has the wavelength of that alkaline metal vapor, and the other alkaline vapor being illuminated by light which has the wavelength of that other alkaline vapor

  13. Nuclear magnetic resonance imaging

    International Nuclear Information System (INIS)

    Young, I.R.

    1984-01-01

    In a method of imaging a body in which nuclear magnetic resonance is excited in a region including part of the body, and the free induction decay signal is measured, a known quantity of a material of known nuclear magnetic resonance properties, for example a bag of water, is included in the region so as to enhance the measured free induction decay signal. This then reduces the generation of noise during subsequent processing of the signal. (author)

  14. Vision therapy in adults with convergence insufficiency: clinical and functional magnetic resonance imaging measures.

    Science.gov (United States)

    Alvarez, Tara L; Vicci, Vincent R; Alkan, Yelda; Kim, Eun H; Gohel, Suril; Barrett, Anna M; Chiaravalloti, Nancy; Biswal, Bharat B

    2010-12-01

    This research quantified clinical measurements and functional neural changes associated with vision therapy in subjects with convergence insufficiency (CI). Convergence and divergence 4° step responses were compared between 13 control adult subjects with normal binocular vision and four CI adult subjects. All CI subjects participated in 18 h of vision therapy. Clinical parameters quantified throughout the therapy included: nearpoint of convergence, recovery point of convergence, positive fusional vergence at near, near dissociated phoria, and eye movements that were quantified using peak velocity. Neural correlates of the CI subjects were quantified with functional magnetic resonance imaging scans comparing random vs. predictable vergence movements using a block design before and after vision therapy. Images were quantified by measuring the spatial extent of activation and the average correlation within five regions of interests (ROI). The ROIs were the dorsolateral prefrontal cortex, a portion of the frontal lobe, part of the parietal lobe, the cerebellum, and the brain stem. All measurements were repeated 4 months to 1 year post-therapy in three of the CI subjects. Convergence average peak velocities to step stimuli were significantly slower (p = 0.016) in CI subjects compared with controls; however, significant differences in average peak velocities were not observed for divergence step responses (p = 0.30). The investigation of CI subjects participating in vision therapy showed that the nearpoint of convergence, recovery point of convergence, and near dissociated phoria significantly decreased. Furthermore, the positive fusional vergence, average peak velocity from 4° convergence steps, and the amount of functional activity within the frontal areas, cerebellum, and brain stem significantly increased. Several clinical and cortical parameters were significantly correlated. Convergence peak velocity was significantly slower in CI subjects compared with controls

  15. Motion-Corrected Real-Time Cine Magnetic Resonance Imaging of the Heart: Initial Clinical Experience.

    Science.gov (United States)

    Rahsepar, Amir Ali; Saybasili, Haris; Ghasemiesfe, Ahmadreza; Dolan, Ryan S; Shehata, Monda L; Botelho, Marcos P; Markl, Michael; Spottiswoode, Bruce; Collins, Jeremy D; Carr, James C

    2018-01-01

    Free-breathing real-time (RT) imaging can be used in patients with difficulty in breath-holding; however, RT cine imaging typically experiences poor image quality compared with segmented cine imaging because of low resolution. Here, we validate a novel unsupervised motion-corrected (MOCO) reconstruction technique for free-breathing RT cardiac images, called MOCO-RT. Motion-corrected RT uses elastic image registration to generate a single heartbeat of high-quality data from a free-breathing RT acquisition. Segmented balanced steady-state free precession (bSSFP) cine images and free-breathing RT images (Cartesian, TGRAPPA factor 4) were acquired with the same spatial/temporal resolution in 40 patients using clinical 1.5 T magnetic resonance scanners. The respiratory cycle was estimated using the reconstructed RT images, and nonrigid unsupervised motion correction was applied to eliminate breathing motion. Conventional segmented RT and MOCO-RT single-heartbeat cine images were analyzed to evaluate left ventricular (LV) function and volume measurements. Two radiologists scored images for overall image quality, artifact, noise, and wall motion abnormalities. Intraclass correlation coefficient was used to assess the reliability of MOCO-RT measurement. Intraclass correlation coefficient showed excellent reliability (intraclass correlation coefficient ≥ 0.95) of MOCO-RT with segmented cine in measuring LV function, mass, and volume. Comparison of the qualitative ratings indicated comparable image quality for MOCO-RT (4.80 ± 0.35) with segmented cine (4.45 ± 0.88, P = 0.215) and significantly higher than conventional RT techniques (3.51 ± 0.41, P cine (1.51 ± 0.90, P = 0.088 and 1.23 ± 0.45, P = 0.182) were not different. Wall motion abnormality ratings were comparable among different techniques (P = 0.96). The MOCO-RT technique can be used to process conventional free-breathing RT cine images and provides comparable quantitative assessment of LV function and volume

  16. Laser magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Ferrari, C.A.

    1985-01-01

    The technique of laser resonance magnetic resonance allows one to study the high-resolution spectroscopy of transient paramagnetic species, viz, atoms, radicals, and molecular ions. This article is a brief exposition of the method, describing the principles, instrumentation and applicability of the IR and FIR-LMR and shows results of HF + . (Author) [pt

  17. Nuclear Magnetic Resonance Spectroscopy

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 9; Issue 1. Nuclear Magnetic Resonance Spectroscopy. Susanta Das. General Article Volume 9 Issue 1 January 2004 pp 34-49. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/009/01/0034-0049. Keywords.

  18. Encephalic magnetic resonance imaging in spinal clinical forms of multiple sclerosis

    International Nuclear Information System (INIS)

    Lubetzki, C.; Lyon-Caen, O.; Lhermitte, F.; Iba-Zizen, M.T.

    1988-01-01

    The diagnosis of multiple sclerosis (MS) in patients presenting with signs and symptoms of pure spinal cord involvement is always difficult. Previous studies have shown the usefulness of encephalic magnetic resonance imaging (MRI) of the brain in those cases. The aim was to evaluate the diagnosis value of brain MRI in medullar forms of MS. 3 refs

  19. Perinatal mortality: clinical value of postmortem magnetic resonance imaging compared with autopsy in routine obstetric practice

    NARCIS (Netherlands)

    Alderliesten, Marianne E.; Peringa, Jan; van der Hulst, Victor P. M.; Blaauwgeers, Hans L. G.; van Lith, Jan M. M.

    2003-01-01

    Objective To compare postmortem magnetic resonance imaging (MRI) with autopsy in perinatal deaths. To determine the acceptance and feasibility of postmortem perinatal MRI. Design Cohort study. Setting Large teaching hospital. Population Fetuses and neonates from 16 weeks gestational age until 28

  20. Correlation of computed tomography, magnetic resonance imaging and clinical outcome in acute carbon monoxide poisoning.

    Science.gov (United States)

    Ozcan, Namik; Ozcam, Giray; Kosar, Pinar; Ozcan, Ayse; Basar, Hulya; Kaymak, Cetin

    2016-01-01

    Carbon monoxide is a toxic gas for humans and is still a silent killer in both developed and developing countries. The aim of this case series was to evaluate early radiological images as a predictor of subsequent neuropsychological sequelae, following carbon monoxide poisoning. After carbon monoxide exposure, early computed tomography scans and magnetic resonance imaging findings of a 52-year-old woman showed bilateral lesions in the globus pallidus. This patient was discharged and followed for 90 days. The patient recovered without any neurological sequela. In a 58-year-old woman exposed to carbon monoxide, computed tomography showed lesions in bilateral globus pallidus and periventricular white matter. Early magnetic resonance imaging revealed changes similar to that like in early tomography images. The patient recovered and was discharged from hospital. On the 27th day of exposure, the patient developed disorientation and memory impairment. Late magnetic resonance imaging showed diffuse hyperintensity in the cerebral white matter. White matter lesions which progress to demyelination and end up in neuropsychological sequelae cannot always be diagnosed by early computed tomography and magnetic resonance imaging in carbon monoxide poisoning. Copyright © 2014 Sociedade Brasileira de Anestesiologia. Published by Elsevier Editora Ltda. All rights reserved.

  1. Current technological advances in magnetic resonance with critical impact for clinical diagnosis and therapy.

    Science.gov (United States)

    Runge, Val M

    2013-12-01

    The last 5 years of technological advances with major impact on clinical magnetic resonance (MR) are discussed, with greater emphasis on those that are most recent. These developments have already had a critical positive effect on clinical diagnosis and therapy and presage continued rapid improvements for the next 5 years. This review begins with a discussion of 2 topics that encompass the breadth of MR, in terms of anatomic applications, contrast media, and MR angiography. Subsequently, innovations are discussed by anatomic category, picking the areas with the greatest development, starting with the brain, moving forward to the liver and kidney, and concluding with the musculoskeletal system, breast, and prostate. Two final topics are then considered, which will likely, with time, become independent major fields in their own right, interventional MR and MR positron emission tomography (PET).The next decade will bring a new generation of MR contrast media, with research focused on substantial improvements (>100-fold) in relaxivity (contrast effect), thus providing greater efficacy, safety, and tissue targeting. Magnetic resonance angiography will see major advances because of the use of compressed sensing, in terms of spatial and temporal resolution, with movement away from nondynamic imaging. The breadth of available techniques and tissue contrast has greatly expanded in brain imaging, benefiting both from the introduction of new basic categories of imaging techniques, such as readout-segmented echo planar imaging and 3D fast spin echo imaging with variable flip angles, and from new refinements specific to anatomic areas, such as double inversion recovery and MP2RAGE. Liver imaging has benefited from the development of techniques to easily and rapidly assess lipid, and will see, overall, a marked improvement in the next 5 years from new techniques on the verge of clinical introduction, such as controlled aliasing in parallel imaging results in higher acceleration

  2. Magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Meyerhoff, D.J.; Weiner, M.W.

    1989-01-01

    A major function of the liver is regulation of carbohydrate, lipid, and nitrogen metabolism. Food is absorbed by the intestines and transported to the liver by the portal circulation. Substrates are metabolized and stored in the liver to maintain optimal blood concentrations of glucose and lipids. Ammonia generated in the gastrointestinal tract is converted to urea in the liver by the urea cycle. Various forms of liver disease are associated with disorders of carbohydrate, fat, and nitrogen metabolism. Therefore the ability to characterize liver metabolism noninvasively is of potential diagnostic value. Magnetic resonance spectroscopy (MRS) provides information about tissue metabolism by measuring concentrations of metabolites. However, to determine the anatomic location from which spectroscopic signals are derived, MRS could be performed in conjunction with MRI. This paper summarizes the current experience with spectroscopy ion animal models of human disease and reviews the clinical experience with hepatic MRS to date

  3. Magnetic resonance in neuroborreliosis

    International Nuclear Information System (INIS)

    Ustymowicz, A.; Zajkowska, J.

    2003-01-01

    Magnetic resonance (MR) is commonly used in diagnosing infections of the central nervous system. The aim of the study is to evaluate central nervous system changes in neuroborreliosis patients. MR examinations were performed in 44 patients with clinical symptoms, epidemiology and laboratory tests results of neuroborreliosis. Abnormalities were detected in 22 patients. Most of them presented cortico-subcortical atrophy (86%). In 9 cases foci of increased signal in T2-weighted and FLAIR images were observed in white matter. They were single or multiple, located subcorticaly and paraventriculary. In 2 subjects areas of increased signal were found in the brain stem. Central nervous system abnormalities detected with MR are not specific for Lyme disease. They can suggest demyelinating lesions and/or gliosis observed in many nervous system disorders (SM, ADEM, lacunar infarcts). (author)

  4. Clinical findings of intracranial vertebral artery disease using magnetic resonance angiography.

    Science.gov (United States)

    Liu, Lu-Han; Chen, Clayton Chi-Chang; Chang, Ming-Hong

    2004-09-01

    The vertebral artery lesion has a variety of clinical characteristics. We sought to clarify the clinical patterns and the location of the intracranial vertebral artery (ICVA) diseases according to analyses of images obtained using magnetic resonance angiography (MRA). We studied vascular lesions, risk factors, symptoms, signs, and outcomes in 35 patients with ICVA disease (3 had bilateral occlusion; 9, unilateral occlusion; 6, bilateral stenosis; and 17, unilateral stenosis). The most common site of unilateral and bilateral lesions was the distal ICVA after the origin of posterior inferior cerebellar artery (PICA). We found accompanying basilar artery disease in 28.6% of patients with unilateral and bilateral ICVA disease. The majority of the ICVA lesions were associated with internal carotid arteries disease (48.8%). The common vascular risk factors were hypertension (71%), diabetes mellitus (34%), hyperlipidemia (31%), smoking (29%), and coronary artery disease (23%). Eighteen patients (51.4%) had transient ischemic attacks (TIAs) only, 10 patients (28.6%) had TIAs before stroke, and 5 patients (14.3%) had strokes without TIAs. Most patients (80%) with TIAs, with or without stroke, had multiple episodes. Vertigo or dizziness, ataxia, limbs weakness and abnormal gait were the common symptoms and signs. At 6 months follow-up, 66.7% patients had no symptoms or only slight symptoms that caused no disability. Our data showed (1) the usual location of ICVA disease (occlusion or severe stenosis) was distal to PICA, especially near the vertebrobasilar junction; (2) the risk factors were hypertension, diabetes mellitus, hyperlipidemia, smoking, and coronary artery disease; (3) patients with ICVA disease had a high frequency of accompanying internal carotid, middle cerebral, or basilar artery disease; (4) vertigo or dizziness, and ataxia were the common symptoms and signs; (5) TIA was the most common clinical pattern; (6) the outcome was favorable, except in cases with

  5. Nuclear magnetic resonance apparatus

    International Nuclear Information System (INIS)

    Lambert, R.

    1991-01-01

    In order to include the effect of a magnetic object in a subject under investigation, Nuclear Magnetic Resonance (NMR) apparatus is operable at more than one radio frequency (RF) frequency. The apparatus allows normal practice as far as obtaining an NMR response or image from a given nuclear species is concerned, but, in addition, interrogates the nuclear spin system at a frequency which is different from the resonance frequency normally used for the given nuclear species, as determined from the applied magnetic field. The magnetic field close to a magnetised or magnetisable object is modified and the given nuclear species gives a response at the different frequency. Thus detection of a signal at the frequency indicates the presence of the chosen nuclei close to the magnetised or magnetisable object. Applications include validation of an object detection or automatic shape inspection system in the presence of magnetic impurities, and the detection of magnetic particles which affect measurement of liquid flow in a pipe. (author)

  6. Clinical usefulness of cardiac cine magnetic resonance imaging in patients with atrial fibrillation

    Energy Technology Data Exchange (ETDEWEB)

    Sakakura, Kazuyoshi; Anno, Hirofumi; Kondo, Takeshi [Fujita Health Univ., Toyoake, Aichi (Japan); and others

    1993-05-01

    We studied the clinical usefulness of cine mode magnetic resonance (MR) imaging in patients with atrial fibrillation (AF) from aspects of image quality and cardiac function. The signal-to-noise (S/N) ratio in the myocardium was significantly (p<0.05) lower in patients with AF than those with normal sinus rhythm. Two radiologists who did not know any patient's information evaluated the image quality visually by marking method on a scale of 12 points. There was no difference of image quality between the two groups. The standard deviation of R-R interval was significantly (r=-0.92, p<0.001) correlated with the S/N ratio in myocardium. Consequently, it was not favorable to estimate visually cardiac cine MR image in patients with AF, when standard deviation of R-R interval was large. The left ventricular (LV) end diastolic, end systolic and stroke volumes and ejection fraction were closely (r=0.82[approx]0.95, p<0.05[approx]0.001) correlated between MR imaging and M-mode echocardiography, respectively. The ability to detect left side valvular regurgitation was almost equal in both MR imaging and color Doppler echocardiography. This result was coincided to previous papers in patients with normal sinus rhythm. In conclusion, cine mode MR imaging was also useful to analyze cardiac function and detect valvular regurgitation in patients with AF. (author).

  7. Clinical significance of magnetic resonance imaging of skeletal muscles in idiopathic inflammatory myopathies of adults

    Energy Technology Data Exchange (ETDEWEB)

    Nishikai, Masahiko; Akiya, Kumiko [National Tokyo Medical Center (Japan)

    2000-12-01

    The purpose of this study was to evaluate the clinical significance of magnetic resonance imaging (MRI) of skeletal muscles in Japanese patients with idiopathic inflammatory myopathies (IIM). MRI was performed in 23 adult patients with IIM, including 10 with polymyositis, 12 with dermatomyositis, and 1 with focal myositis. Seven (73%) of 11 patients with active IIM and 2 (17%) of 12 patients with inactive IIM showed hyperintensity of T2-weighted images and normal intensity of T1-weighted images, indicating 'edema-like abnormalities' (MRI findings for active myositis). Muscle lipomatosis and fibrosis were demonstrated in four patients and 1 patient, respectively. Considerable selectivity of muscles in developing inflammatory disorders was found. In quadriceps muscles, for example, vastus muscles seemed to be more often affected in DM patients, whereas adductors were more often affected in PM patients. Serial examination of muscle MRIs was carried out in 4 patients and the findings paralleled the disease activities. The muscle MRI findings did not necessarily correlate with other findings, such as the presence of muscle weakness, elevated serum creatine kinase levels, myogenic electromyogram, or muscle biopsy findings. The muscle MRI was considered to be an additional useful tool for the diagnosis, evaluation of disease activity, and planning treatment of IIM. (author)

  8. Clinical significance of magnetic resonance imaging of skeletal muscles in idiopathic inflammatory myopathies of adults

    International Nuclear Information System (INIS)

    Nishikai, Masahiko; Akiya, Kumiko

    2000-01-01

    The purpose of this study was to evaluate the clinical significance of magnetic resonance imaging (MRI) of skeletal muscles in Japanese patients with idiopathic inflammatory myopathies (IIM). MRI was performed in 23 adult patients with IIM, including 10 with polymyositis, 12 with dermatomyositis, and 1 with focal myositis. Seven (73%) of 11 patients with active IIM and 2 (17%) of 12 patients with inactive IIM showed hyperintensity of T2-weighted images and normal intensity of T1-weighted images, indicating 'edema-like abnormalities' (MRI findings for active myositis). Muscle lipomatosis and fibrosis were demonstrated in four patients and 1 patient, respectively. Considerable selectivity of muscles in developing inflammatory disorders was found. In quadriceps muscles, for example, vastus muscles seemed to be more often affected in DM patients, whereas adductors were more often affected in PM patients. Serial examination of muscle MRIs was carried out in 4 patients and the findings paralleled the disease activities. The muscle MRI findings did not necessarily correlate with other findings, such as the presence of muscle weakness, elevated serum creatine kinase levels, myogenic electromyogram, or muscle biopsy findings. The muscle MRI was considered to be an additional useful tool for the diagnosis, evaluation of disease activity, and planning treatment of IIM. (author)

  9. Clinical significance of pontine high signals identified on magnetic resonance imaging

    International Nuclear Information System (INIS)

    Watanabe, Masaki; Takahashi, Akira; Arahata, Yutaka; Motegi, Yoshimasa; Furuse, Masahiro.

    1993-01-01

    Spin-echo magnetic resonance imaging (MRI) was evaluated to 530 cases in order to investigate the clinical significance of pontine high signals. The subjects comprised 109 cases of pontine infarction with high signal on T 2 -weighted image and low signal on T 1 -weighted image (PI group), 145 of pontine high signal with high signal on T 2 -weighted image but normal signal on T 1 -weighted image (PH group) and 276 of age-matched control without abnormality either on T 1 or T 2 -weighted images (AC group). Subjective complaints such as vertigo-dizziness were more frequent in the PH group than in the PI group. In both PI and groups, periventricular hyperintensity as well as subcortical high signals in the supratentorium were more severe than in the AC group. These degrees were higher in the PI group than in the PH group. In conclusion, PH as well as PI may result from diffuse arteriosclerosis and PH is considered to be an early finding of pontine ischemia. (author)

  10. Clinical significance of pontine high signals identified on magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Masaki; Takahashi, Akira (Nagoya Univ. (Japan). Faculty of Medicine); Arahata, Yutaka; Motegi, Yoshimasa; Furuse, Masahiro

    1993-07-01

    Spin-echo magnetic resonance imaging (MRI) was evaluated to 530 cases in order to investigate the clinical significance of pontine high signals. The subjects comprised 109 cases of pontine infarction with high signal on T[sub 2]-weighted image and low signal on T[sub 1]-weighted image (PI group), 145 of pontine high signal with high signal on T[sub 2]-weighted image but normal signal on T[sub 1]-weighted image (PH group) and 276 of age-matched control without abnormality either on T[sub 1] or T[sub 2]-weighted images (AC group). Subjective complaints such as vertigo-dizziness were more frequent in the PH group than in the PI group. In both PI and groups, periventricular hyperintensity as well as subcortical high signals in the supratentorium were more severe than in the AC group. These degrees were higher in the PI group than in the PH group. In conclusion, PH as well as PI may result from diffuse arteriosclerosis and PH is considered to be an early finding of pontine ischemia. (author).

  11. Temporomandibular joint involvement in juvenile idiopathic arthritis: clinical predictors of magnetic resonance imaging signs

    Energy Technology Data Exchange (ETDEWEB)

    Argyropoulou, Maria I.; Margariti, Persefoni N.; Astrakas, Loukas; Kosta, Paraskevi [Medical School University of Ioannina, Department of Radiology, Ioannina (Greece); Karali, Aikaterini; Alfandaki, Sapfo; Siamopoulou, Antigoni [University of Ioannina, Department of Child Health, Medical School, Ioannina (Greece)

    2009-03-15

    The aim of the study was to define clinical predictors of magnetic resonance imaging (MRI) findings of temporomandibular joint (TMJ) involvement in juvenile idiopathic arthritis (JIA). Forty-six patients, aged 2.08-36.7 years, with JIA (oligoartitular 18, polyarticular 17, systemic type 11) were examined with standard plain and contrast-enhanced sequences. Of 88 TMJs examined, an abnormal condyle was observed in 32%, flattened articular eminence in 27%, flattened articular disk in 17%, intra-articular fluid in 10%, enhancing pannus in 45% and restricted condylar motion in 9%. Logistic regression analysis revealed that for abnormal condyle and flattened articular eminence, independent predictors were type of JIA (P < 0.015), age at onset (P < 0.038), and duration of disease activity (P < 0.001). Plots of the logistic regression models showed that TMJ involvement approached certainty for systemic sooner than for the other JIA types. Pannus was present with probability >0.5 when the disease started before 4 years of age. In conclusion, the systemic type of JIA, young age at onset and long duration of activity are risk factors for TMJ damage. MRI of the TMJ should be performed in patients who are less than 4 years of age at the onset of JIA, and in those with the systemic type, whatever the age of onset. (orig.)

  12. Temporomandibular joint involvement in juvenile idiopathic arthritis: clinical predictors of magnetic resonance imaging signs

    International Nuclear Information System (INIS)

    Argyropoulou, Maria I.; Margariti, Persefoni N.; Astrakas, Loukas; Kosta, Paraskevi; Karali, Aikaterini; Alfandaki, Sapfo; Siamopoulou, Antigoni

    2009-01-01

    The aim of the study was to define clinical predictors of magnetic resonance imaging (MRI) findings of temporomandibular joint (TMJ) involvement in juvenile idiopathic arthritis (JIA). Forty-six patients, aged 2.08-36.7 years, with JIA (oligoartitular 18, polyarticular 17, systemic type 11) were examined with standard plain and contrast-enhanced sequences. Of 88 TMJs examined, an abnormal condyle was observed in 32%, flattened articular eminence in 27%, flattened articular disk in 17%, intra-articular fluid in 10%, enhancing pannus in 45% and restricted condylar motion in 9%. Logistic regression analysis revealed that for abnormal condyle and flattened articular eminence, independent predictors were type of JIA (P 0.5 when the disease started before 4 years of age. In conclusion, the systemic type of JIA, young age at onset and long duration of activity are risk factors for TMJ damage. MRI of the TMJ should be performed in patients who are less than 4 years of age at the onset of JIA, and in those with the systemic type, whatever the age of onset. (orig.)

  13. Clinical magnetic resonance imaging. Frequent incidental cerebral findings; Klinische Magnetresonanztomographie. Haeufige zerebrale Zufallsbefunde

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, A.; Ditter, P.; Schild, H.H.; Hattingen, E. [Universitaetsklinikum Bonn, Funktionseinheit Neuroradiologie der Klinik fuer Radiologie, Bonn (Germany); Weidauer, S. [St.-Katharinen-Krankenhaus, Neurologische Klinik, Frankfurt/M (Germany)

    2017-04-15

    The increasing use of magnetic resonance imaging (MRI) in clinical diagnostics means that patients and physicians are confronted more often with incidental findings. In the literature there are fluctuating data on the incidence of such findings and guidelines concerning the further procedure exist in only very few cases, such as incidental aneurysms and pituitary adenomas. The diagnostic and therapeutic implications which can be derived from incidental findings depend on multiple factors, such as anatomical location, patient age, comorbidity and patient wishes. For this reason it often makes sense to refer patients with incidental findings to an interdisciplinary neurological center at an early stage. In this review frequent incidental cerebral findings, epidemiological data, imaging criteria and, where possible, recommendations for the further procedure are shown. (orig.) [German] Durch den gehaeuften Einsatz der MRT in der zerebralen Diagnostik werden Arzt und Patienten in zunehmendem Masse mit Zufallsbefunden, auch Nebenbefunde genannt, konfrontiert. In der Literatur existieren sehr schwankende Angaben zur Haeufigkeit solcher Zufallsbefunde. Nur fuer einzelne dieser Befunde, wie z. B. das inzidentelle Aneurysma oder das Hypophysenadenom, existieren Leitlinien fuer das weitere Prozedere. Die aus einem Zufallsbefund abzuleitenden diagnostischen und therapeutischen Konsequenzen sind von vielen Faktoren, wie z. B. der anatomischen Lage, dem Patientenalter, den Komorbiditaeten und dem Patientenwunsch abhaengig. Daher ist es oft sinnvoll, den Patienten mit einem Zufallsbefund fruehzeitig in einem interdisziplinaeren Neurozentrum vorzustellen. In der vorliegenden Arbeit werden haeufige zerebrale Zufallsbefunde mit epidemiologischen Daten, bildgebenden Kriterien und - wenn moeglich - Empfehlungen bzgl. des weiteren Vorgehens gezeigt. (orig.)

  14. Cardiac Magnetic Resonance-Verified Myocardial Fibrosis in Chagas Disease: Clinical Correlates and Risk Stratification

    Directory of Open Access Journals (Sweden)

    Marly Uellendahl

    Full Text Available Abstract Background: Chagas disease (CD is an important cause of heart failure and mortality, mainly in Latin America. This study evaluated the morphological and functional characteristics of the heart as well the extent of myocardial fibrosis (MF in patients with CD by cardiac magnetic resonance (CMR. The prognostic value of MF evaluated by myocardial-delayed enhancement (MDE was compared with that via Rassi score. Methods: This study assessed 39 patients divided into 2 groups: 28 asymptomatic patients as indeterminate form group (IND; and symptomatic patients as Chagas Heart Disease (CHD group. All patients underwent CMR using the techniques of cine-MRI and MDE, and the amount of MF was compared with the Rassi score. Results: Regarding the morphological and functional analysis, significant differences were observed between both groups (p < 0.001. Furthermore, there was a strong correlation between the extent of MF and the Rassi score (r = 0.76. Conclusions: CMR is an important technique for evaluating patients with CD, stressing morphological and functional differences in all clinical presentations. The strong correlation with the Rassi score and the extent of MF detected by CMR emphasizes its role in the prognostic stratification of patients with CD.

  15. Understanding Magnetic Resonance Imaging of Knee Cartilage Repair: A Focus on Clinical Relevance.

    Science.gov (United States)

    Hayashi, Daichi; Li, Xinning; Murakami, Akira M; Roemer, Frank W; Trattnig, Siegfried; Guermazi, Ali

    2017-06-01

    The aims of this review article are (a) to describe the principles of morphologic and compositional magnetic resonance imaging (MRI) techniques relevant for the imaging of knee cartilage repair surgery and their application to longitudinal studies and (b) to illustrate the clinical relevance of pre- and postsurgical MRI with correlation to intraoperative images. First, MRI sequences that can be applied for imaging of cartilage repair tissue in the knee are described, focusing on comparison of 2D and 3D fast spin echo and gradient recalled echo sequences. Imaging features of cartilage repair tissue are then discussed, including conventional (morphologic) MRI and compositional MRI techniques. More specifically, imaging techniques for specific cartilage repair surgery techniques as described above, as well as MRI-based semiquantitative scoring systems for the knee cartilage repair tissue-MR Observation of Cartilage Repair Tissue and Cartilage Repair OA Knee Score-are explained. Then, currently available surgical techniques are reviewed, including marrow stimulation, osteochondral autograft, osteochondral allograft, particulate cartilage allograft, autologous chondrocyte implantation, and others. Finally, ongoing research efforts and future direction of cartilage repair tissue imaging are discussed.

  16. Computer simulation of a clinical magnet resonance tomography scanner for training purposes

    International Nuclear Information System (INIS)

    Hacklaender, T.; Mertens, H.; Cramer, B.M.

    2004-01-01

    Purpose: The idea for this project was born by the necessity to offer medical students an easy approach to the theoretical basics of magnetic resonance imaging. The aim was to simulate the features and functions of such a scanner on a commercially available computer by means of a computer program. Materials and Methods: The simulation was programmed in pure Java under the GNU General Public License and is freely available for a commercially available computer with Windows, Macintosh or Linux operating system. The graphic user interface is oriented to a real scanner. In an external program parameter, images for the proton density and the relaxation times T1 and T2 are calculated on the basis of clinical examinations. From this, the image calculation is carried out in the simulation program pixel by pixel on the basis of a pulse sequence chosen and modified by the user. The images can be stored and printed. In addition, it is possible to display and modify k-space images. Results: Seven classes of pulse sequences are implemented and up to 14 relevant sequence parameters, such as repetition time and echo time, can be altered. Aliasing and motion artifacts can be simulated. As the image calculation only takes a few seconds, interactive working is possible. (orig.)

  17. [Computer simulation of a clinical magnet resonance tomography scanner for training purposes].

    Science.gov (United States)

    Hackländer, T; Mertens, H; Cramer, B M

    2004-08-01

    The idea for this project was born by the necessity to offer medical students an easy approach to the theoretical basics of magnetic resonance imaging. The aim was to simulate the features and functions of such a scanner on a commercially available computer by means of a computer program. The simulation was programmed in pure Java under the GNU General Public License and is freely available for a commercially available computer with Windows, Macintosh or Linux operating system. The graphic user interface is oriented to a real scanner. In an external program parameter, images for the proton density and the relaxation times T1 and T2 are calculated on the basis of clinical examinations. From this, the image calculation is carried out in the simulation program pixel by pixel on the basis of a pulse sequence chosen and modified by the user. The images can be stored and printed. In addition, it is possible to display and modify k-space images. Seven classes of pulse sequences are implemented and up to 14 relevant sequence parameters, such as repetition time and echo time, can be altered. Aliasing and motion artifacts can be simulated. As the image calculation only takes a few seconds, interactive working is possible. The simulation has been used in the university education for more than 1 year, successfully illustrating the dependence of the MR images on the measuring parameters. This should facititate the approach of students to the understanding MR imaging in the future.

  18. Clinical Application of Magnetic Resonance Imaging in Management of Breast Cancer Patients Receiving Neoadjuvant Chemotherapy

    Directory of Open Access Journals (Sweden)

    Jeon-Hor Chen

    2013-01-01

    Full Text Available Neoadjuvant chemotherapy (NAC, also termed primary, induction, or preoperative chemotherapy, is traditionally used to downstage inoperable breast cancer. In recent years it has been increasingly used for patients who have operable cancers in order to facilitate breast-conserving surgery, achieve better cosmetic outcome, and improve prognosis by reaching pathologic complete response (pCR. Many studies have demonstrated that magnetic resonance imaging (MRI can assess residual tumor size after NAC, and that provides critical information for planning of the optimal surgery. NAC also allows for timely adjustment of administered drugs based on response, so ineffective regimens could be terminated early to spare patients from unnecessary toxicity while allowing other effective regimens to work sooner. This review article summarizes the clinical application of MRI during NAC. The use of different MR imaging methods, including dynamic contrast-enhanced MRI, proton MR spectroscopy, and diffusion-weighted MRI, to monitor and evaluate the NAC response, as well as how changes of parameters measured at an early time after initiation of a drug regimen can predict final treatment outcome, are reviewed. MRI has been proven a valuable tool and will continue to provide important information facilitating individualized image-guided treatment and personalized management for breast cancer patients undergoing NAC.

  19. Clinical study on magnetic resonance imaging of lacunar infarcts and cerebrovascular high-risk group

    Energy Technology Data Exchange (ETDEWEB)

    Hironaka, Masatoshi (Hiroshima Univ. (Japan). School of Medicine)

    1990-04-01

    Magnetic resonance imaging (MRI) study was performed in 32 patients with recent lacunar stroke. T2-weighted images showed ischemic lesions more clearly than T1-weighted images. Sixty-six percent of 32 patients had periventricular lesions. Eighty-four percent had subcortical white matter lesions. Sixty-nine percent had lesions in basal ganglia. Twenty-eight percent had lesions in brainstem. Periventricular lesions were revealed symmetrically. On the other hand, lesions in other areas were not detected symmetrically. Severe periventricular lesions on MRI were similar to those of Binswanger's disease. Patients with severe periventricular lesions had often hypertension. Moreover, two of them had dementia. Twenty-three patients with transient ischemic attack had less remarkable lesions than patients with lacunar stroke. Thirty-seven patients with a history of cerebrovascular risk factors (hypertension, diabetes mellitus) had severer lesions compared with normal controls. Sixty-one percent of controls, who had no cerebrovascular symptoms and signs, had MRI lesions. These results suggest that MRI is useful for detection of cerebral ischemic lesions with no associated clinical symptoms or signs. (author).

  20. Knee dislocations: a magnetic resonance imaging study correlated with clinical and operative findings

    Energy Technology Data Exchange (ETDEWEB)

    Bui, Kimmie L. [Cleveland Clinic, Department of Radiology, Cleveland, OH (United States); Cleveland Clinic, Department of Radiology, HB6, Cleveland, OH (United States); Ilaslan, Hakan; Sundaram, Murali [Cleveland Clinic, Department of Radiology, Cleveland, OH (United States); Parker, Richard D. [Cleveland Clinic, Department of Orthopaedics, Cleveland, OH (United States)

    2008-07-15

    Our objectives were to determine retrospectively the prevalence, patients' demographics, mechanism of injury, combination of torn ligaments, associated intra-articular and extra-articular injuries, fractures, bone bruises, femoral-tibial alignment and neurovascular complications of knee dislocations as evaluated by magnetic resonance (MR) imaging. From 17,698 consecutive knee examinations by magnetic resonance imaging (MRI) over a 6-year period, 20 patients with knee dislocations were identified. The medical records of these patients were subsequently reviewed for relevant clinical history, management and operative findings. The prevalence of knee dislocations was 0.11% [95% confidence interval (95% CI) 0.06-0.16]. There were 16 male patients and four female patients, with ages ranging from 15 years to 76 years (mean 31 years). Fifteen patients had low-velocity injuries (75%), of which 11 were amateur sports related and four were from falls. Four patients (20%) had suffered high-velocity trauma (motor vehicle accidents). One patient had no history available. Anatomic alignment was present at imaging in 16 patients (80%). Eighteen patients had three-ligament tears, two had four-ligament tears. The four-ligament tears occurred with low-velocity injuries. The anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) were torn in every patient; the lateral collateral ligament (LCL) was torn in 50%, and the medial collateral ligament (MCL) in 60%. Intra-articular injuries included meniscal tears (five in four patients), fractures (eight in seven patients), bone bruises (15 patients), and patellar retinaculum tears (eight partial, two complete). The most common extra-articular injury was a complete biceps femoris tendon tear (five, 25%). There were two popliteal tendon tears and one iliotibial band tear. One patient had received a vascular injury following a motor vehicle accident (MVA) and had been treated prior to undergoing MRI. Bone bruises

  1. Transarterial embolization for uterine fibroids: clinical success rate and results of magnetic resonance imaging

    International Nuclear Information System (INIS)

    Kroencke, T.J.; Scheurig, C.; Kluener, C.; Fischer, T.; Klessen, C.; Rudolph, J.; Siara, K.; Zimmermann, E.; Hamm, B.; Gauruder-Burmester, A.; Gronewold, M.

    2005-01-01

    Purpose: to analyze the clinical success rate and the findings of magnetic resonance imaging (MRI) after uterine artery embolization of symptomatic leiomyomas (fibroids) of the uterus. Materials and methods: this is a prospective single-center case study of 80 consecutively treated patients, followed for 3-6 months (group I), 7-12 months, (group II), and 13-25 months (group III). MRI was used to determine the uterine volume and size of the dominant leiomyoma. Symptoms and causes requiring repeat interventions were analyzed. Results: significant (p < 0.01) volume reduction of the uterus (median: 34.95% confidence interval [CI]: 30.41 - 41.76%) and dominant leiomyoma (median: 52.07%, CI: 47.71 - 61.57%) was found. The decrease in uterine volume (I-III: 22.68%, 33.56%, 47.93%) and dominant leiomyoma volume (I-III: 41.86%, 62.16%, 73.96%) progressed with the follow-up time. Bleeding resolved significantly (p < 0.0001) in all three follow-up groups (groups I-III: 92.86%, 95.23%, 96.67%). Furthermore, urinary frequency (groups I-III: 70%, 75%, 82.35%) and sensation of pelvic pressure (groups I-III: 42.86%, 60%, 93.75%) improved, which was statistically significant in group III (p < 0.01). The number of leiomyomas correlated (p < 0.05) with improvement of the bleeding and the pelvic pressure. Repeat therapy was necessary for complications in four patients (5%) and for therapeutic failure in three patients (3.8%). Permanent amenorrhea was observed in four patients (5%) of age 45 years or older. Conclusion: uterine artery embolization of uterine leiomyomas has a high clinical success rate with an acceptable incidence of complications and repeat interventions. (orig.)

  2. [Localized Scleroderma of Lower Extremities:Clinical and Magnetic Resonance Imaging Features].

    Science.gov (United States)

    Wang, Feng-dan; Wang, Hong-wei; Wu, Zhi-hong; Hou, Bo; Jiang, Bo; Zhang, Yan; Feng, Feng; Jin, Zheng-yu; Yuan, Xie

    2015-08-01

    To evaluate the clinical and musculoskeletal characteristics of localized scleroderma with lower extremities affected. All the localized scleroderma patients,who received magnetic resonance (MR ) examinations of affected lower extremities at Peking Union Medical College Hospital from April 2013 to June 2014,were retrospectively reviewed. Their clinical data and laboratory results of antinuclear antibody,anti-double stranded-DNA antibody, and anti-extractable nuclear antigen antibody were collected and analyzed. All the MR examinations were non-contrast imaging using Siemens Skyra 3.0T MR scanner. There were 16 localized scleroderma patients with lower extremities affected, 11 of whom were linear scleroderma, 4 generalized morphea, and 1 deep morphea. Female to male ratio was 1:2.2. The mean age was 22.5 years. The mean time span was 7.4 years. Four of the 14 patients (28.6%) who received antinuclear antibody test were positive. All the 10 patients who received anti-double stranded-DNA antibody test and the 7 patients who received anti-extractable nuclear antigen antibody test were negative. The most common musculoskeletal MR features were subcutaneous septal thickening (16/16) and fascial thickening (11/16). The thickened speta and fascia could either be hypointenstiy or hyperintensity on turbo inversion recovery magnitude/proton density weighted imaging. Other MR manifestations were intramuscular speta thickening (3/16), muscular abnormal signals (1/16), and bone marrow abnormal signals (2/16). Musculoskeletal manifestations of the lower extremities with localized scleroderma can be well revealed using MR imaging.

  3. Clinical utility of magnetic resonance imaging radiographs for suspected organic syndromes in adult psychiatry.

    Science.gov (United States)

    Erhart, Stephen M; Young, Alexander S; Marder, Stephen R; Mintz, Jim

    2005-08-01

    In psychiatric practice, adult patients are most commonly referred for magnetic resonance imaging (MRI) to screen for suspected organic medical diseases of the central nervous system that can mimic psychiatric syndromes. We identified the most common signs and symptoms prompting MRIs to establish the predictive value of these signs and symptoms for clinically pertinent organic syndromes. This study was a retrospective chart review of psychiatric patients at the Veterans Affairs Greater Los Angeles Health Care Center (Los Angeles, Calif.) who were referred for MRI of the brain between 1996 and 2002. Patients referred for evaluation of dementia were excluded. The specific indications leading clinicians to obtain MRI were identified and grouped. In order to offset the uncertain significance of many MRI findings, for this study, the predictive value of each indication was calculated based on the percentage of patients in whom clinical management changed in response to MRI findings rather than on the percentage with any abnormal MRI results. Of 253 patients who had MRIs, 38 (15%) incurred some degree of treatment modification as a result of MRI findings, including 6 patients in whom MRI identified a medical condition that became the focus of treatment. Six indications appeared most likely to prompt clinicians to obtain MRIs. Because pertinent results were associated with each of these indications, statistical evaluation did not reveal significant differences in their predictive values (chi(2) = 4.32, df = 5, p = .505). Unlike prior studies showing no value to screening radioimaging, this study shows MRI can be a useful screening test among patients suspected of having organic psychiatric disorders and that the common indications for MRI employed at one institution were predictive.

  4. Online Magnetic Resonance Image Guided Adaptive Radiation Therapy: First Clinical Applications

    International Nuclear Information System (INIS)

    Acharya, Sahaja; Fischer-Valuck, Benjamin W.; Kashani, Rojano; Parikh, Parag; Yang, Deshan; Zhao, Tianyu; Green, Olga; Wooten, Omar; Li, H. Harold; Hu, Yanle; Rodriguez, Vivian; Olsen, Lindsey; Robinson, Clifford; Michalski, Jeff; Mutic, Sasa; Olsen, Jeffrey

    2016-01-01

    Purpose: To demonstrate the feasibility of online adaptive magnetic resonance (MR) image guided radiation therapy (MR-IGRT) through reporting of our initial clinical experience and workflow considerations. Methods and Materials: The first clinically deployed online adaptive MR-IGRT system consisted of a split 0.35T MR scanner straddling a ring gantry with 3 multileaf collimator-equipped "6"0Co heads. The unit is supported by a Monte Carlo–based treatment planning system that allows real-time adaptive planning with the patient on the table. All patients undergo computed tomography and MR imaging (MRI) simulation for initial treatment planning. A volumetric MRI scan is acquired for each patient at the daily treatment setup. Deformable registration is performed using the planning computed tomography data set, which allows for the transfer of the initial contours and the electron density map to the daily MRI scan. The deformed electron density map is then used to recalculate the original plan on the daily MRI scan for physician evaluation. Recontouring and plan reoptimization are performed when required, and patient-specific quality assurance (QA) is performed using an independent in-house software system. Results: The first online adaptive MR-IGRT treatments consisted of 5 patients with abdominopelvic malignancies. The clinical setting included neoadjuvant colorectal (n=3), unresectable gastric (n=1), and unresectable pheochromocytoma (n=1). Recontouring and reoptimization were deemed necessary for 3 of 5 patients, and the initial plan was deemed sufficient for 2 of the 5 patients. The reasons for plan adaptation included tumor progression or regression and a change in small bowel anatomy. In a subsequently expanded cohort of 170 fractions (20 patients), 52 fractions (30.6%) were reoptimized online, and 92 fractions (54.1%) were treated with an online-adapted or previously adapted plan. The median time for recontouring, reoptimization, and QA was 26

  5. Online Magnetic Resonance Image Guided Adaptive Radiation Therapy: First Clinical Applications

    Energy Technology Data Exchange (ETDEWEB)

    Acharya, Sahaja; Fischer-Valuck, Benjamin W.; Kashani, Rojano; Parikh, Parag; Yang, Deshan; Zhao, Tianyu; Green, Olga; Wooten, Omar; Li, H. Harold; Hu, Yanle; Rodriguez, Vivian; Olsen, Lindsey; Robinson, Clifford; Michalski, Jeff; Mutic, Sasa; Olsen, Jeffrey, E-mail: jolsen@radonc.wustl.edu

    2016-02-01

    Purpose: To demonstrate the feasibility of online adaptive magnetic resonance (MR) image guided radiation therapy (MR-IGRT) through reporting of our initial clinical experience and workflow considerations. Methods and Materials: The first clinically deployed online adaptive MR-IGRT system consisted of a split 0.35T MR scanner straddling a ring gantry with 3 multileaf collimator-equipped {sup 60}Co heads. The unit is supported by a Monte Carlo–based treatment planning system that allows real-time adaptive planning with the patient on the table. All patients undergo computed tomography and MR imaging (MRI) simulation for initial treatment planning. A volumetric MRI scan is acquired for each patient at the daily treatment setup. Deformable registration is performed using the planning computed tomography data set, which allows for the transfer of the initial contours and the electron density map to the daily MRI scan. The deformed electron density map is then used to recalculate the original plan on the daily MRI scan for physician evaluation. Recontouring and plan reoptimization are performed when required, and patient-specific quality assurance (QA) is performed using an independent in-house software system. Results: The first online adaptive MR-IGRT treatments consisted of 5 patients with abdominopelvic malignancies. The clinical setting included neoadjuvant colorectal (n=3), unresectable gastric (n=1), and unresectable pheochromocytoma (n=1). Recontouring and reoptimization were deemed necessary for 3 of 5 patients, and the initial plan was deemed sufficient for 2 of the 5 patients. The reasons for plan adaptation included tumor progression or regression and a change in small bowel anatomy. In a subsequently expanded cohort of 170 fractions (20 patients), 52 fractions (30.6%) were reoptimized online, and 92 fractions (54.1%) were treated with an online-adapted or previously adapted plan. The median time for recontouring, reoptimization, and QA was 26

  6. Pre-clinical functional magnetic resonance imaging. Pt. II. The heart

    Energy Technology Data Exchange (ETDEWEB)

    Messner, Nadja M.; Zoellner, Frank G.; Kalayciyan, Raffi; Schad, Lothar R. [Heidelberg Univ., Mannheim (Germany). Computer Assisted Clinical Medicine

    2014-07-01

    One third of all deaths worldwide in 2008 were caused by cardiovascular diseases (CVD), and the incidence of CVD related deaths rises ever more. Thus, improved imaging techniques and modalities are needed for the evaluation of cardiac morphology and function. Cardiac magnetic resonance imaging (CMRI) is a minimally invasive technique that is increasingly important due to its high spatial and temporal resolution, its high soft tissue contrast and its ability of functional and quantitative imaging. It is widely accepted as the gold standard of cardiac functional analysis. In the short period of small animal MRI, remarkable progress has been achieved concerning new, fast imaging schemes as well as purpose-built equipment. Dedicated small animal scanners allow for tapping the full potential of recently developed animal models of cardiac disease. In this paper, we review state-of-the-art cardiac magnetic resonance imaging techniques and applications in small animals at ultra-high fields (UHF).

  7. The clinical study on high intensity zone of magnetic resonance imaging using Scolopendrid Aquacupuncture.

    Directory of Open Access Journals (Sweden)

    Jeong-a Lim

    2006-12-01

    Full Text Available Objective : This study was designed to find out the effect of scolopendrid aquacupuncture on low back pain with or without sciatica showing high intensity zone of magnetic resonance imaging. Methods : The 30 patients who had a diagnosis of high intensity zone by lumbar-MRI and admitted to Gwangju oriental medical hospital in wonkwang university from January 2005 to August 2004 were observed. The symptom of inpatients is low back pain with or without sciatica. We treated 30 patients by scolopendrid aquacupuncture besides the general conservative treatment of oriental medicine. Results and Conclusion : The scolopendrid aquacupuncture treatment led to improvement in the pain and symptom of disability as determined by all efficacy measures. After scolopendrid aquacupuncture treatment, there was improvement in VAS, ROM and SLRT. This results suggest that scolopendrid aquacupuncture is good method for treatment of low back pain with or without sciatica showing high intensity zone of magnetic resonance imaging.

  8. Recommendations concerning magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    1986-01-01

    In medicine the technique of nuclear magnetic resonance (NMR) is applied in the form of in vivo nuclear magnetic resonance spectroscopy (MRS). In vivo MRS can be carried out non-invasively. The committee of the Dutch Health Council briefly discusses the qualities and potentialities of the nuclei that will probably be used in future clinical spectroscopy: 31 P, 13 C, 1 H (and possibly 19 F and 23 Na). The committee discusses several possibilities of combining imaging and spectroscopy. The imaging of nuclei other than protons is also possible with MRS. Potential applications are considered in oncology, cardiology, neurology and hepatology. (Auth.)

  9. Clinical diagnostic criteria of multiple sclerosis: the role of magnetic resonance imaging

    International Nuclear Information System (INIS)

    Belair, M.; Girard, M.

    2004-01-01

    The objective of this article is to summarize the diagnostic criteria recommended by the International Panel on the Diagnosis of Multiple Sclerosis in 2001. The recommendations of another working group, the Consortium of Multiple Sclerosis Centers Consensus Meeting, which met in Vancouver in 2001, concerning the diagnosis and follow-up of patients with multiple sclerosis are also presented in an effort to standardize the protocols for magnetic resonance imaging of these patients. (author)

  10. Nuclear magnetic resonance scattering

    International Nuclear Information System (INIS)

    Young, I.R.

    1985-01-01

    A nuclear magnetic resonance apparatus is described including a magnet system which is capable of providing a steady magnetic field along an axis, and is constructed so as to define a plurality of regions along the axis in each of which the field is substantially homogeneous so that in each region an imaging operation may be separately carried out. Iron shields increase the field homogeneity. In use, each patient lies on a wheeled trolley which is provided with magnetic field gradient coils and an RF coil system, some of the coils being movable to facilitate positioning of the patient, and there are terminals for connection to a common computing and control facility. (author)

  11. Advances in magnetic resonance 10

    CERN Document Server

    Waugh, John S

    2013-01-01

    Advances in Magnetic Resonance, Volume 10, presents a variety of contributions to the theory and practice of magnetic resonance. The book contains three chapters that examine superoperators in magnetic resonance; ultrasonically modulated paramagnetic resonance; and the utility of electron paramagnetic resonance (EPR) and electron-nuclear double-resonance (ENDOR) techniques for studying low-frequency modes of atomic fluctuations and their significance for understanding the mechanism of structural phase transitions in solids.

  12. Disease activity in longstanding ankylosing spondylitis: a correlation of clinical and magnetic resonance imaging findings.

    Science.gov (United States)

    Goh, L; Suresh, P; Gafoor, A; Hughes, P; Hickling, P

    2008-04-01

    We evaluated magnetic resonance imaging (MRI) changes in ankylosing spondylitis (AS) patients with longstanding disease and investigated whether there is any relationship between MRI findings and validated methods of disease assessment. A total of 34 AS patients with disease duration greater than 10 years were included in this observational cross-sectional study (26 men, 8 women). The main outcome measures were Bath Ankylosing Spondylitis Functional Index (BASFI), Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Bath Ankylosing Spondylitis Global assessment (BASG), Bath Ankylosing Spondylitis Metrology Index (BASMI), MRI of the thoracic and lumbar spine (AS spi MRI A) and measurement of serum erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), plasma viscosity (PV) and immunoglobulin A (Ig A). The median scores for the acute lesions based on AS spi MRI A scoring system was 2.5 (0-4.12). The respective mean ESR and CRP were 36 (SD, 24.00) mm/h and 14.19 (SD, 24.00) mg/l with the median PV of 1.8 (1.75-1.87). The median BASG, BASFI and BASDAI were 4.55 (2.37-5.55), 4.40(2.31-5.47) and 4.32 (3.07-6.48), respectively. No significant correlations were found between the acute MRI scores and each of the clinical instruments and laboratory markers of inflammation. In this study, majority of AS patients with longstanding disease had very low AS spi MRI A scores or no evidence of spinal inflammatory lesions. Our study would suggest that MRI should be used along with other measures of disease activity in the assessment of symptomatic AS patients with longstanding disease.

  13. Correlation of clinical and magnetic resonance imaging findings in hips of elite female ballet dancers.

    Science.gov (United States)

    Duthon, Victoria B; Charbonnier, Caecilia; Kolo, Frank C; Magnenat-Thalmann, Nadia; Becker, Christophe D; Bouvet, Cindy; Coppens, Elia; Hoffmeyer, Pierre; Menetrey, Jacques

    2013-03-01

    To understand why professional female ballet dancers often complain of inguinal pain and experience early hip osteoarthritis (OA). Goals were to examine clinical and advanced imaging findings in the hips of dancers compared with those in a matched cohort of nondancers and to assess the femoral head translation in the forward split position using magnetic resonance imaging (MRI). Twenty professional female ballet dancers and 14 active healthy female individuals matched for age (control group) completed a questionnaire on hip pain and underwent hip examination with impingement tests and measurement of passive hip range of motion (ROM). All had a pelvic 1.5 T MRI in the back-lying position to assess femoroacetabular morphologic features and lesions. For the dancers, additional MR images were acquired in the split position to evaluate femoroacetabular congruency. Twelve of 20 dancers complained of groin pain only while dancing; controls were asymptomatic. Dancers' passive hip ROM was normal. No differences in α neck angle, acetabular depth, acetabular version, and femoral neck anteversion were found between dancers and controls. MRI of dancers while performing splits showed a mean femoral head subluxation of 2.05 mm. MRI of dancers' hips showed labral tears, cartilage thinning, and herniation pits, located in superior and posterosuperior positions. Lesions were the same for symptomatic and asymptomatic dancers. Controls had proportionally the same number of labral lesions but in an anterosuperior position. They also had 2 to 3 times fewer cartilage lesions and pits than did dancers. The results of our study are consistent with our hypothesis that repetitive extreme movements can cause femoral head subluxations and femoroacetabular abutments in female ballet dancers with normal hip morphologic features, which could result in early OA. Pathologic changes seen on MRI were symptomatic in less than two thirds of the dancers. Level IV, therapeutic case series. Copyright

  14. Clinical significance of magnetic resonance imaging (MRI) in evaluation of the extension of uterine cervical cancer

    International Nuclear Information System (INIS)

    Matsubara, Masaru

    1993-01-01

    Magnetic resonance imaging (MRI) was performed in 62 patients with uterine cervical cancer and the preoperative MRI findings were compared with the pathological findings following surgery. The surgical stages of 62 patients were 2 at stage 0, 18 at stage Ia, 19 at stage Ib, 9 at stage IIa, 11 at stage IIb, 2 at stage IIIa, and 1 at stage IIIb. The MRI findings in the present study included: (1) the existence of a high intensity area (HIA) in the uterine cervix or minimum thickness of residual normal cervical tissue, (2) necrotic cavity, (3) pyometra, (4) irregular margin of the cervix, (5) parametrial invasion, (6) vaginal invasion, (7) bladder invasion, and (8) lymph node enlargement. No HIA was observed in any patient with stage 0 or stage Ia, in 8 patients with stage Ib, and in 2 patients with stage IIa, while all patients with cancer tissues greater than 10 mm in diameter had a HIA. In 39 patients in whom hysterectomy was undergone without conization, the findings of MRI correlated significantly (r=0.929, p<0.001) with the minimum thickness of residual normal cervical tissue by the pathological measurement. When the irregular margin of the cervix was regarded as a disruption of the cervical myo-metrium by cancer tissue, accuracy was 87%. Furthermore, the degrees of accuracy for parametrial invasion, vaginal invasion and bladder invasion were 92%, 90% and 94%, respectively. When lymphnodes greater than 15 mm in diameter were regarded as a positive in MRI, accuracy was 88%. The present results indicate that MRI is clinically effective in preoperatively evaluating the extension of uterine cervical cancer. (author)

  15. Virtual phantom magnetic resonance imaging (ViP MRI) on a clinical MRI platform.

    Science.gov (United States)

    Saint-Jalmes, Hervé; Bordelois, Alejandro; Gambarota, Giulio

    2018-01-01

    The purpose of this study was to implement Virtual Phantom Magnetic Resonance Imaging (ViP MRI), a technique that allows for generating reference signals in MR images using radiofrequency (RF) signals, on a clinical MR system and to test newly designed virtual phantoms. MRI experiments were conducted on a 1.5 T MRI scanner. Electromagnetic modelling of the ViP system was done using the principle of reciprocity. The ViP RF signals were generated using a compact waveform generator (dimensions of 26 cm × 18 cm × 16 cm), connected to a homebuilt 25 mm-diameter RF coil. The ViP RF signals were transmitted to the MRI scanner bore, simultaneously with the acquisition of the signal from the object of interest. Different types of MRI data acquisition (2D and 3D gradient-echo) as well as different phantoms, including the Shepp-Logan phantom, were tested. Furthermore, a uniquely designed virtual phantom - in the shape of a grid - was generated; this newly proposed phantom allows for the investigations of the vendor distortion correction field. High quality MR images of virtual phantoms were obtained. An excellent agreement was found between the experimental data and the inverse cube law, which was the expected functional dependence obtained from the electromagnetic modelling of the ViP system. Short-term time stability measurements yielded a coefficient of variation in the signal intensity over time equal to 0.23% and 0.13% for virtual and physical phantom, respectively. MR images of the virtual grid-shaped phantom were reconstructed with the vendor distortion correction; this allowed for a direct visualization of the vendor distortion correction field. Furthermore, as expected from the electromagnetic modelling of the ViP system, a very compact coil (diameter ~ cm) and very small currents (intensity ~ mA) were sufficient to generate a signal comparable to that of physical phantoms in MRI experiments. The ViP MRI technique was successfully implemented on a clinical MR

  16. Indications for and clinical procedures resulting from magnetic resonance imaging of the knee in older patients

    Science.gov (United States)

    Parent, Marc-Etienne; Vézina, François; Carrier, Nathalie; Masetto, Ariel

    2018-01-01

    Abstract Objective To analyze the indications for and clinical procedures resulting from knee magnetic resonance imaging (MRI) in older patients. Design We retrospectively analyzed 215 medical records of patients 50 years of age and older who had undergone a unilateral knee MRI in 2009. Setting Centre hospitalier universitaire de Sherbrooke in Quebec. Participants Patients 50 years of age and older who underwent a knee MRI in 2009. Main outcome measures The main outcome measure was an invasive procedure in the same knee that underwent an MRI. Medical charts were reviewed up to 2014 for patient characteristics, MRI indication, ordering physician specialty, radiography before MRI, MRI findings, and clinical procedures resulting from the MRI. Results The patients’ mean (SD) age was 60.6 (7.5) years. The main MRI indications were meniscopathy (148 [68.8%]) and chronic pain (92 [42.8%]). The main MRI findings were osteoarthritis (OA) (185 [86.0%]) and meniscal lesions (170 [79.1%]). Only 82 (38.1%) patients had a plain radiograph in the 24 months preceding the MRI, usually without a standing anteroposterior view. Findings on pre-MRI radiography (n = 201) demonstrated OA in 144 (71.6%) patients. Overall, 87 (40.5%) patients were seen by an orthopedic surgeon and 27 (31.0%) of these patients underwent an invasive intervention. Among the 81 patients with moderate to severe OA on MRI, 36 (44.4%) had radiographic evidence of moderate to severe OA and only 3 (3.7%) underwent arthroscopic meniscectomy. Conclusion Our study reproduces the known association between OA and degenerative meniscal changes in older patients. We have found a surprising underuse of the standing anteroposterior view on radiography. Most patients in our cohort could have been appropriately diagnosed and treated based on such radiographic information, as demonstrated by pre-MRI findings, thus avoiding the MRI and subsequent evaluation by an orthopedic surgeon. Meniscectomy was rarely performed

  17. Imaging by magnetic resonance

    International Nuclear Information System (INIS)

    Duroure, J.F.; Serpolay, H.; Vallens, D.

    1995-01-01

    Here are described the advanced technology for nuclear magnetic resonance imaging: reduction of acquisition times, and rebuilding times, images quality improvement. The tendency is to open the machines at low and middle field, on a market being at 10% of NMR I sales, with economical, scientifical and ergonomic reasons broadly developed by constructors

  18. Magnetic resonance fingerprinting.

    Science.gov (United States)

    Ma, Dan; Gulani, Vikas; Seiberlich, Nicole; Liu, Kecheng; Sunshine, Jeffrey L; Duerk, Jeffrey L; Griswold, Mark A

    2013-03-14

    Magnetic resonance is an exceptionally powerful and versatile measurement technique. The basic structure of a magnetic resonance experiment has remained largely unchanged for almost 50 years, being mainly restricted to the qualitative probing of only a limited set of the properties that can in principle be accessed by this technique. Here we introduce an approach to data acquisition, post-processing and visualization--which we term 'magnetic resonance fingerprinting' (MRF)--that permits the simultaneous non-invasive quantification of multiple important properties of a material or tissue. MRF thus provides an alternative way to quantitatively detect and analyse complex changes that can represent physical alterations of a substance or early indicators of disease. MRF can also be used to identify the presence of a specific target material or tissue, which will increase the sensitivity, specificity and speed of a magnetic resonance study, and potentially lead to new diagnostic testing methodologies. When paired with an appropriate pattern-recognition algorithm, MRF inherently suppresses measurement errors and can thus improve measurement accuracy.

  19. Functional Magnetic Resonance Imaging

    Science.gov (United States)

    Voos, Avery; Pelphrey, Kevin

    2013-01-01

    Functional magnetic resonance imaging (fMRI), with its excellent spatial resolution and ability to visualize networks of neuroanatomical structures involved in complex information processing, has become the dominant technique for the study of brain function and its development. The accessibility of in-vivo pediatric brain-imaging techniques…

  20. Nuclear magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Rueterjans, H.

    1987-01-01

    Contributions by various authors who are working in the field of NMR imaging present the current status and the perspectives of in-vivo nuclear magnetic resonance spectroscopy, explaining not only the scientific and medical aspects, but also technical and physical principles as well as questions concerning practical organisation and training, and points of main interest for further research activities. (orig./TRV) [de

  1. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    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 ( ...

  2. 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 ...

  3. Magnetic Resonance Imaging of Stroke

    NARCIS (Netherlands)

    Bouts, Mark. J. R. J.; Wu, O.; Dijkhuizen, R. M.

    2017-01-01

    Magnetic resonance imaging (MRI) provides a powerful (neuro)imaging modality for the diagnosis and outcome prediction after (acute) stroke. Since MRI allows noninvasive, longitudinal, and three-dimensional assessment of vessel occlusion (with magnetic resonance angiography (MRA)), tissue injury

  4. Magnetic resonance of phase transitions

    CERN Document Server

    Owens, Frank J; Farach, Horacio A

    1979-01-01

    Magnetic Resonance of Phase Transitions shows how the effects of phase transitions are manifested in the magnetic resonance data. The book discusses the basic concepts of structural phase and magnetic resonance; various types of magnetic resonances and their underlying principles; and the radiofrequency methods of nuclear magnetic resonance. The text also describes quadrupole methods; the microwave technique of electron spin resonance; and the Mössbauer effect. Phase transitions in various systems such as fluids, liquid crystals, and crystals, including paramagnets and ferroelectrics, are also

  5. Magnetic resonance imaging. 1

    International Nuclear Information System (INIS)

    Wall, E.E. van der; Roos, A.A. de; Doornbos, J.; Dijkman, P.R.M. van; Matheijssen, N.A.A.; Laarse, A. van der; Krauss, X.H.; Blokland, J.A.k.; Manger Cats, V.; Voorthuisen, A.E. van; Bruschke, A.V.G.

    1991-01-01

    The cardiovascular applications of MRI in coronary artery disease have considerably increased in recent years. Although many applications overlap those of other more cost-effective techniques, such as echocardiography, radionuclide angiography, and CT, MRI offers unique features not shared by the conventional techniques. Technical advantages are the excellent spatial resolution, the characterization of myocardial tissue, and the potential for three-dimensional imaging. This allows the accurate assessment of left ventricular mass and volume, the differentiation of infarcted tissue from normal myocardial tissue, and the determination of systolic wall thickening and regional wall motion abnormalities. Also inducible myocardial ischemia using pharmacological stress (dipyramidole or dobutamine) may be assessed by magnetic resonance imaging. Future technical developments include real-time imaging and noninvasive visualization of the coronary arteries. These advantages will have a major impact on the application of MRI in coronary artery disease, potentially unsurpassed by other techniques and certainly justifying the expenses. Consequently, the clinical use of MRI for the detection of coronary artery disease largely depends on the progress of technical developments. (author). 134 refs.; 10 figs.; 2 tabs

  6. Three-dimensional magnetic resonance imaging of physeal injury: reliability and clinical utility.

    Science.gov (United States)

    Lurie, Brett; Koff, Matthew F; Shah, Parina; Feldmann, Eric James; Amacker, Nadja; Downey-Zayas, Timothy; Green, Daniel; Potter, Hollis G

    2014-01-01

    Injuries to the physis are common in children with a subset resulting in an osseous bar and potential growth disturbance. Magnetic resonance imaging allows for detailed assessment of the physis with the ability to generate 3-dimensional physeal models from volumetric data. The purpose of this study was to assess the interrater reliability of physeal bar area measurements generated using a validated semiautomated segmentation technique and to highlight the clinical utility of quantitative 3-dimensional (3D) physeal mapping in pediatric orthopaedic practice. The Radiology Information System/Picture Archiving Communication System (PACS) at our institution was searched to find consecutive patients who were imaged for the purpose of assessing a physeal bar or growth disturbance between December 2006 and October 2011. Physeal segmentation was retrospectively performed by 2 independent operators using semiautomated software to generate physeal maps and bar area measurements from 3-dimensional spoiled gradient recalled echo sequences. Inter-reliability was statistically analyzed. Subsequent surgical management for each patient was recorded from the patient notes and surgical records. We analyzed 24 patients (12M/12F) with a mean age of 11.4 years (range, 5-year to 15-year olds) and 25 physeal bars. Of the physeal bars: 9 (36%) were located in the distal tibia; 8 (32%) in the proximal tibia; 5 (20%) in the distal femur; 1 (4%) in the proximal femur; 1 (4%) in the proximal humerus; and 1 (4%) in the distal radius. The independent operator measurements of physeal bar area were highly correlated with a Pearson correlation coefficient (r) of 0.96 and an intraclass correlation coefficient for average measures of 0.99 (95% confidence interval, 0.97-0.99). Four patients underwent resection of the identified physeal bars, 9 patients were treated with epiphysiodesis, and 1 patient underwent bilateral tibial osteotomies. Semiautomated segmentation of the physis is a reproducible

  7. Children's (Pediatric) Magnetic Resonance Imaging

    Science.gov (United States)

    ... Physician Resources Professions Site Index A-Z Children’s (Pediatric) Magnetic Resonance Imaging Children’s magnetic resonance imaging (MRI) ... limitations of Children’s (Pediatric) MRI? What is Children’s (Pediatric) MRI? Magnetic resonance imaging (MRI) is a noninvasive ...

  8. Children's (Pediatric) Magnetic Resonance Imaging

    Medline Plus

    Full Text Available ... Physician Resources Professions Site Index A-Z Children’s (Pediatric) Magnetic Resonance Imaging Children’s magnetic resonance imaging (MRI) ... limitations of Children’s (Pediatric) MRI? What is Children’s (Pediatric) MRI? Magnetic resonance imaging (MRI) is a noninvasive ...

  9. 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 ...

  10. Children's (Pediatric) Magnetic Resonance Imaging

    Medline Plus

    Full Text Available ... News Physician Resources Professions Site Index A-Z Children’s (Pediatric) Magnetic Resonance Imaging Children’s magnetic resonance imaging ( ... the limitations of Children’s (Pediatric) MRI? What is Children’s (Pediatric) MRI? Magnetic resonance imaging (MRI) is a ...

  11. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    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 ...

  12. Magnetic resonance imaging of radiation optic neuropathy

    International Nuclear Information System (INIS)

    Zimmerman, C.F.; Schatz, N.J.; Glaser, J.S.

    1990-01-01

    Three patients with delayed radiation optic neuropathy after radiation therapy for parasellar neoplasms underwent magnetic resonance imaging. The affected optic nerves and chiasms showed enlargement and focal gadopentetate dimeglumine enhancement. The magnetic resonance imaging technique effectively detected and defined anterior visual pathway changes of radionecrosis and excluded the clinical possibility of visual loss because of tumor recurrence

  13. Clinical application of diffusion-weighted magnetic resonance imaging to intracranial disorders

    Energy Technology Data Exchange (ETDEWEB)

    Yanaka, Kiyoyuki; Shirai, Shizuo; Kimura, Hiroshi [Soujinkai Hospital, Ibaraki (Japan); Kamezaki, Takao; Matsumura, Akira; Nose, Tadao

    1995-09-01

    Diffusion-weighted magnetic resonance imaging was performed to determine the changes in water diffusion and to investigate the detectability of diffusion anisotropy in patients with intracranial disorders. Diffusion maps of the apparent diffusion coefficient (ADC) were created of 19 patients with cerebral infarction, five with intracerebral hematoma, four with glioma, four with meningioma, four with hydrocephalus, and five with subdural hematoma. ADC was increased in chronic cerebral infarction and glioma, and decreased in acute cerebral infarction, meningioma, and the marginal area of glioma compared with the ADC of the normal gray matter. There was a significant difference in ADC between the marginal and internal areas of glioma. Increased ADC may be due to increased vasogenic edema in infarction and a lack of significant restriction of diffusion within glioma. Decreased ADC can be attributed to restricted diffusion caused by cytotoxic edema in infarction and the underlying histological pattern of densely packed tumor cells in glioma. Diffusion anisotropy of the internal capsule was less detectable in pathological than normal hemispheres. Diffusion anisotropy was less detectable in patients with hydrocephalus and subdural hematoma. Intracranial lesions were thought to have influenced the compression of the brain structures and cells, resulting in decreased diffusion. The measurement of ADC by diffusion-weighted magnetic resonance imaging has the potential for greater understanding of the biophysical changes in various intracranial disorders, including correct diagnosis of cerebral infarction, and histological diagnosis of brain tumor. (author).

  14. Magnetic resonance imaging findings of a metastatic chemodectoma in a dog : clinical communication

    Directory of Open Access Journals (Sweden)

    S.H. Naudé

    2006-06-01

    Full Text Available A 6-year-old, male, Collie-cross was presented with a non-weight bearing right thoracic limb lameness, right m.deltoideus, m.infraspinatus and m.supraspinatus atrophy, and severe neck pain with spasm of the cervical epaxial muscles. MRI revealed complete destruction of the 5th and 6th cervical vertebral bodies with lateral extradural spinal cord compression at the level of the 4th and 5th cervical vertebrae. These lesions were very clearly demonstrated on magnetic resonance images, while only subtle changes were seen on survey radiographs. Post mortem investigation revealed a large heart base chemodectoma with multiple smaller tumours in the cranial mediastinum and a single tumour nodule on the thoracic aorta. The 5th cervical vertebral body had necrotic, haemorrhagic and lytic changes. Histopathology of the heart base tumour, the nodules in the cranial mediastinum and on the thoracic aorta and samples from the 5th cervical vertebra confirmed the presence of a malignant aortic or carotid body tumour originating from the chemoreceptor organs. Diagnostic imaging features and post mortem findings are described. To our knowledge, this is the first report of the magnetic resonance features of a metastatic chemodectoma in a dog.

  15. Magnetic resonance imaging: hazard, risk and safety

    International Nuclear Information System (INIS)

    Narayan, Pradeep; Suri, S.; Singh, P.

    2001-01-01

    The hazard and risk associated with magnetic resonance imaging is a matter of concern. In 1982, the Food and Drug Administration (FDA), USA issued guidelines to Hospital's Investigational Review Board (IRBs) in 'Guidelines for Evaluating Electromagnetic Exposure Risks for Trials of Clinical Nuclear Magnetic Resonance (NMR)'. In 1997, the Berufsgenossenschaft (BG), professional association for precision engineering and electronics of Germany, in their preliminary proposal for safety limits extended their concerns on static magnetic field. Owing to both time varying and static magnetic fields applied in Magnetic Resonance Imaging (MRI) this became of immediate concern to user community to assess the potential hazard and risk associated with the NMR system

  16. Measurements of Pulmonary Artery Size for Assessment of Pulmonary Hypertension by Cardiovascular Magnetic Resonance and Clinical Application

    Directory of Open Access Journals (Sweden)

    Fan YANG

    2017-02-01

    Full Text Available Background and objective Pulmonary hypertension (PH often leads to dilatation of main pulmonary artery (MPA. MPA measurements can be used to predict PH. This aim of this study is to investigate power of MPA vessel indices, which are acquired from cardiovascular magnetic resonance, to evaluate PH. Methods Cardiovascular-magnetic-resonance-determined parameters of MPA were acquired and calculated in 83 PH patients, whose diagnosis were confirmed with right heart catheterization and 49 healthy volunteers; these parameters included MPA diameter (DPA, ratio of DPA and ascending aorta diameter (DPA/DAo, max mean diameter (MDmax, min mean diameter (MDmin, fraction transverse diameter (fTD, fraction longitudinal diameter (fLD, and distensibility. Results Compared with control group, DPA, DPA/DAo, MDmax, and MDmin were significantly higher in patients with PH (P28.4 mm, and MDmax>32.4 mm (area under the curve, AUC=0.979, 0.981 showed best performance in predicting PH, yielding highest specificity at 100%. Conclusion Noninvasive cardiovascular-magnetic-resonance-derived MPA measurements provide excellent and practical reference in clinical settings for detecting PH.

  17. Magnetic resonance instrumentation

    International Nuclear Information System (INIS)

    Bell, R.A.

    1987-01-01

    Magnetic resonance (MR), while opening new vistas to diagnostic medicine, utilizes equipment that is unfamiliar to most clinicians. Beyond learning to cope with new terms, such as spin-echo, T1, T2, and spin density, health care professionals are faced with the inclusion of magnetic and radiofrequency effects in their facilities produced by a complex array of devices. It is the purpose of this chapter to outline the components of an MR imaging system, to discuss their functions, and to note the variations in equipment commercially available

  18. Adenosine stress cardiovascular magnetic resonance with variable-density spiral pulse sequences accurately detects coronary artery disease: initial clinical evaluation.

    Science.gov (United States)

    Salerno, Michael; Taylor, Angela; Yang, Yang; Kuruvilla, Sujith; Ragosta, Michael; Meyer, Craig H; Kramer, Christopher M

    2014-07-01

    Adenosine stress cardiovascular magnetic resonance perfusion imaging can be limited by motion-induced dark-rim artifacts, which may be mistaken for true perfusion abnormalities. A high-resolution variable-density spiral pulse sequence with a novel density compensation strategy has been shown to reduce dark-rim artifacts in first-pass perfusion imaging. We aimed to assess the clinical performance of adenosine stress cardiovascular magnetic resonance using this new perfusion sequence to detect obstructive coronary artery disease. Cardiovascular magnetic resonance perfusion imaging was performed during adenosine stress (140 μg/kg per minute) and at rest on a Siemens 1.5-T Avanto scanner in 41 subjects with chest pain scheduled for coronary angiography. Perfusion images were acquired during injection of 0.1 mmol/kg Gadolinium-diethylenetriaminepentacetate at 3 short-axis locations using a saturation recovery interleaved variable-density spiral pulse sequence. Significant stenosis was defined as >50% by quantitative coronary angiography. Two blinded reviewers evaluated the perfusion images for the presence of adenosine-induced perfusion abnormalities and assessed image quality using a 5-point scale (1 [poor] to 5 [excellent]). The prevalence of obstructive coronary artery disease by quantitative coronary angiography was 68%. The average sensitivity, specificity, and accuracy were 89%, 85%, and 88%, respectively, with a positive predictive value and negative predictive value of 93% and 79%, respectively. The average image quality score was 4.4±0.7, with only 1 study with more than mild dark-rim artifacts. There was good inter-reader reliability with a κ statistic of 0.67. Spiral adenosine stress cardiovascular magnetic resonance results in high diagnostic accuracy for the detection of obstructive coronary artery disease with excellent image quality and minimal dark-rim artifacts. © 2014 American Heart Association, Inc.

  19. Magnetic resonance imaging

    International Nuclear Information System (INIS)

    Sigal, R.

    1988-01-01

    This book is an introduction to magnetic resonance imaging (MRI). The basic principles for the interpretation of MR images are developed. The book is divided into five chapters: introduction, tissue, parameters, acquisition parameters, contribution to diagnosis, and practical management of an MR examination. Eight exercises allow the reader to test the knowledge he has acquired. Signal localization and MR artefacts are reviewed in an appendix

  20. Magnetic resonance imaging (MRI

    Directory of Open Access Journals (Sweden)

    Takavar A

    1993-04-01

    Full Text Available Basic physical principles of nuclear magnetic resonance imaging (N.M.R.I, a nonionizing medical imaging technique, are described. Principles of NMRI with other conventional imaging methods, ie, isotope scanning, ultrasonography and radiography have been compared. T1 and T2 and spin density (S.D. factors and different image construction techniques based on their different combinations is discussed and at the end physical properties of some N.M.R images is mentioned.

  1. Magnetic resonance imaging (MRI)

    OpenAIRE

    Takavar A

    1993-01-01

    Basic physical principles of nuclear magnetic resonance imaging (N.M.R.I), a nonionizing medical imaging technique, are described. Principles of NMRI with other conventional imaging methods, ie, isotope scanning, ultrasonography and radiography have been compared. T1 and T2 and spin density (S.D.) factors and different image construction techniques based on their different combinations is discussed and at the end physical properties of some N.M.R images is mentioned.

  2. Children's (Pediatric) Magnetic Resonance Imaging

    Medline Plus

    Full Text Available ... magnetic resonance imaging (MRI) uses a powerful magnetic field, radio waves and a computer to produce detailed ... problems, medications, recent surgeries and allergies. The magnetic field is not harmful, but it may cause some ...

  3. Ultrasound/Magnetic Resonance Image Fusion Guided Lumbosacral Plexus Block – A Clinical Study

    DEFF Research Database (Denmark)

    Strid, JM; Pedersen, Erik Morre; Søballe, Kjeld

    2014-01-01

    in a double-blinded randomized controlled trial with crossover design. MR datasets will be acquired and uploaded in an advanced US system (Epiq7, Phillips, Amsterdam, Netherlands). All volunteers will receive SSPS blocks with lidocaine added gadolinium contrast guided by US/MR image fusion and by US one week......Background and aims Ultrasound (US) guided lumbosacral plexus block (Supra Sacral Parallel Shift [SSPS]) offers an alternative to general anaesthesia and perioperative analgesia for hip surgery.1 The complex anatomy of the lumbosacral region hampers the accuracy of the block, but it may be improved...... by guidance of US and magnetic resonance (MR) image fusion and real-time 3D electronic needle tip tracking.2 We aim to estimate the effect and the distribution of lidocaine after SSPS guided by US/MR image fusion compared to SSPS guided by ultrasound. Methods Twenty-four healthy volunteers will be included...

  4. Clinical role of non-contrast magnetic resonance angiography for evaluation of renal artery stenosis

    International Nuclear Information System (INIS)

    Utsunomiya, Daisuke; Nomitsu, Yohei; Komeda, Yosuke; Okigawa, Takashi; Urata, Joji; Miyazaki, Mitsue; Yamashita, Yasuyuki

    2008-01-01

    The association between a gadolinium-based contrast material and nephrogenic systemic fibrosis has been discussed. The purpose of our study was to evaluate whether non-contrast enhanced magnetic resonance angiography (MRA) might provide sufficient information of renal artery stenosis. The non-contrast MRA of 26 patients with hypertension was retrospectively reviewed in the present study. The significant renal artery stenosis was visually evaluated by comparing non-contrast MRA with computed tomography or conventional angiographic finding. Difference of the intensities between the proximal and distal aorta was quantitatively evaluated. The sensitivity, specificity, positive predictive value and negative predictive value of non-contrast MRA in the evaluation of the renal artery stenosis was 78%, 91%, 64% and 96%, respectively. The distal abdominal aorta showed less signal intensity than the proximal aorta by 16.9±12.2%. Non-contrast MRA is a non-invasive and effective method that allows evaluation of the renal artery stenosis. (author)

  5. Magnetic resonance imaging of thoracic hydatid disease; Correlation with clinical findings, radiography, ultrasonography, CT and pathology

    Energy Technology Data Exchange (ETDEWEB)

    Sinner, W.N. von; Rifal, A.; Te Strake, L.; Sieck, J. (King Faisal Specialist Hospital and Research Centre, Riyadh (Saudi Arabia). Dept. of Radiology King Faisal Specialist Hospital and Research Centre, Riyadh (Saudi Arabia). Dept. of Medicine Michigan Univ., Ann Arbor (USA). Dept. of Radiology)

    1990-01-01

    Two patients with thoracic manifestations of hydatid disease (HD) are discussed; one patient had recurrent HD of the chest wall and the other, intrapulmonary HD after rupture and intrathoracic extension of an infradiaphragmatic cyst. At magnetic resonance (MR) imaging the manifestations of HD in the thorax are similar to previously reported MR findings in HD in the liver. The presence of a low signal intensity rim on T2 weighted images representing the cyst wall was confirmed. On T1 weighted images cysts with heterogeneous low and intermediate signal intensity contents and a relatively high signal intensity wall were seen. ''Folded parasitic membranes'' previously not described on MR were noted. Daughter cysts may have a low or high signal intensity depending on contents. Reactive changes in the lung may be quite marked compared with the liver, due to reaction to the parasite or simply because the lung is more easily compressed leading to secondary atelectasis. (orig.).

  6. Feasibility of interactive magnetic resonance imaging of moving anatomy for clinical practice

    DEFF Research Database (Denmark)

    Brix, Lau; Sørensen, Thomas S; Berber, Yasmina

    2014-01-01

    of electrodes during neurosurgery, the diagnostic value of this method is relatively unexplored. Purpose: To test an interactive slice-positioning system with respect to real-time MRI reconstruction for imaging of moving anatomical structures on two different scanner brands by using inexpensive computer......Background: Real-time magnetic resonance imaging (MRI) imaging with real-time reconstruction has been available for some time. The technique acquires and presents the MRI images to the operator the instant they are acquired. However, besides guiding purposes, like catheter tracking and placement...... hardware. Materials and methods: The MRI data were sampled using two acquisition schemes: a Cartesian sampling scheme and a radial sampling scheme based on the golden ratio. Four anatomical targets, which exhibit non-periodic movement, were identified and imaged: movement of the gastric ventricle emptying...

  7. Magnetic resonance tomography in syringomyelia

    International Nuclear Information System (INIS)

    Koehler, D.; Treisch, J.; Hertel, G.; Schoerner, W.; Fiegler, W.; Staedtisches Rudolf-Virchow Krankenhaus, Berlin

    1985-01-01

    Thirteen patients with a clinical diagnosis of syringomyelia were examined by nuclear tomography (0.35 T magnet) in the spin-echo mode. In all thirteen patients, the T1 images (Se 400/35) showed a longitudinal cavity with a signal intensity of CSF. The shape and extent of the syrinx could be adequately demonstrated in 12 of the 13 examinations. Downward displacement of the cerebellar tonsils was seen in eight cases. The examination took between half and one hour. Advantages of magnetic resonance tomography (nuclear tomography) include the absence of artifacts, images in the line of the lesion and its non-invasiveness. (orig.) [de

  8. Clinical use of intravenous gadolinium-DTPA in magnetic resonance imaging of the central nervous system

    International Nuclear Information System (INIS)

    Bydder, G.M.; Niendorf, H.P.; Young, I.R.

    1987-01-01

    Following extensive pharmacological and animal studies clinical trials with intravenous gadolinium-DTPA (Gd-DTPA) were begun at the end of 1983. During 1984 one group in Berlin and another in London conducted clinical trials. During 1985 Gd-DTPA was released more widely and now over 20 groups in Europe and four in the United States are involved in clinical evaluation programmes. Gd-DTPA is the first parenteral magnetic contrast agent available for clinical use and the results of these clinical trials have been followed with considerable interest. In general terms the clinical results with Gd-DTPA parallel those seen with iodinated contrast agents used in X-ray computed tomography (CT) but there are important differences, particularly in relation to the use of pulse sequences and effects due to increased concentration of Gd-DTPA. In this chapter the mode of action of Gd-DTPA is reviewed and the clinical results in the central nervous system are summarised

  9. Introduction lecture to magnetic resonance

    International Nuclear Information System (INIS)

    Conard, J.

    1980-01-01

    This lecture deals with all that is common either to electron paramagnetic resonance (E.P.R.) or to nuclear magnetic resonance (N.M.R.). It will present, in an as elementary form as possible, the main concepts used in magnetic resonance emphasizing some aspects, specific for interface science. (orig./BHO)

  10. Pocket atlas of cranial magnetic resonance imaging

    International Nuclear Information System (INIS)

    Haughton, V.M.; Daniels, D.L.

    1986-01-01

    This atlas illustrates normal cerebral anatomy in magnetic resonance images. From their studies in cerebral anatomy utilizing cryomicrotome and other techniques, the authors selected more than 100 high-resolution images that represent the most clinically useful scans

  11. Limits to magnetic resonance microscopy

    International Nuclear Information System (INIS)

    Glover, Paul; Mansfield, Peter

    2002-01-01

    The last quarter of the twentieth century saw the development of magnetic resonance imaging (MRI) grow from a laboratory demonstration to a multi-billion dollar worldwide industry. There is a clinical body scanner in almost every hospital of the developed nations. The field of magnetic resonance microscopy (MRM), after mostly being abandoned by researchers in the first decade of MRI, has become an established branch of the science. This paper reviews the development of MRM over the last decade with an emphasis on the current state of the art. The fundamental principles of imaging and signal detection are examined to determine the physical principles which limit the available resolution. The limits are discussed with reference to liquid, solid and gas phase microscopy. In each area, the novel approaches employed by researchers to push back the limits of resolution are discussed. Although the limits to resolution are well known, the developments and applications of MRM have not reached their limit. (author)

  12. Comparison of clinical, magnetic resonance and evoked potentials data in a case of valproic-acid-related hyperammonemic coma

    International Nuclear Information System (INIS)

    Hantson, Philippe; Grandin, Cecile; Duprez, Thierry; Nassogne, Marie-Cecile; Guerit, Jean-Michel

    2005-01-01

    Magnetic resonance (MR) multimodality evoked potentials (MEPs) and clinical findings were correlated in a 47-year-old epileptic man in whom parenteral valproic acid (VPA) therapy induced severe comatose hyperammonemic encephalopathy without biological signs of hepatotoxicity (or hepatocytic dysfunction). Although the plasma VPA level remained within a normal therapeutic range, the ammoniemia increased to a toxic peak level at 411 μmol/l 24 h after symptom onset, requiring VPA therapy discontinuation. Brain MR monitoring demonstrated early cytotoxic edema evolving into delayed vasogenic edema and final brain atrophy. Concomitantly to abnormalities within the brainstem on MR images, an increase in brainstem conduction at MEPs and clinical disturbance of brainstem reflexes were observed at the initial phase of the disease course. Later, the resolution of the MR and MEPs abnormalities paralleled the clinical recovery of the reflexes. (orig.)

  13. Comparison of clinical, magnetic resonance and evoked potentials data in a case of valproic-acid-related hyperammonemic coma

    Energy Technology Data Exchange (ETDEWEB)

    Hantson, Philippe [Universite Catholique de Louvain, Department of Intensive Care, Cliniques Saint-Luc, Brussels (Belgium); Grandin, Cecile; Duprez, Thierry [Universite Catholique de Louvain, Department of Neuroradiology, Cliniques Saint-Luc, Brussels (Belgium); Nassogne, Marie-Cecile [Universite Catholique de Louvain, Department of Pediatric Neurology, Cliniques Saint-Luc, Brussels (Belgium); Guerit, Jean-Michel [Universite Catholique de Louvain, Laboratory of Neurophysiology, Cliniques Saint-Luc, Brussels (Belgium)

    2005-01-01

    Magnetic resonance (MR) multimodality evoked potentials (MEPs) and clinical findings were correlated in a 47-year-old epileptic man in whom parenteral valproic acid (VPA) therapy induced severe comatose hyperammonemic encephalopathy without biological signs of hepatotoxicity (or hepatocytic dysfunction). Although the plasma VPA level remained within a normal therapeutic range, the ammoniemia increased to a toxic peak level at 411 {mu}mol/l 24 h after symptom onset, requiring VPA therapy discontinuation. Brain MR monitoring demonstrated early cytotoxic edema evolving into delayed vasogenic edema and final brain atrophy. Concomitantly to abnormalities within the brainstem on MR images, an increase in brainstem conduction at MEPs and clinical disturbance of brainstem reflexes were observed at the initial phase of the disease course. Later, the resolution of the MR and MEPs abnormalities paralleled the clinical recovery of the reflexes. (orig.)

  14. Imaging in the diagnosis and management of peripheral psoriatic arthritis-The clinical utility of magnetic resonance imaging and ultrasonography

    DEFF Research Database (Denmark)

    Østergaard, Mikkel; Eder, Lihi; Christiansen, Sara Nysom

    2016-01-01

    Psoriatic arthritis (PsA) is an inflammatory joint disease characterised by the presence of arthritis and often enthesitis and/or spondylitis in patients with psoriasis. However, it presents a wide range of disease manifestations in various patterns. Imaging is an important part of management of PsA...... or clinical studies. Magnetic resonance imaging (MRI) allows detailed assessment of all peripheral and axial joints involved in PsA, and can visualise both inflammation and structural changes. Ultrasonography (US) can visualise many of the peripheral heterogeneous tissue compartments affected by PsA....... In contrast to MRI, US is not useful for assessing axial involvement in the spine and sacroiliac joints. In this paper, we will provide an overview of the status, strengths and limitations of MRI and US in peripheral PsA in routine clinical practice and clinical trials....

  15. (1)H-Nuclear magnetic resonance-based plasma metabolic profiling of dairy cows with clinical and subclinical ketosis.

    Science.gov (United States)

    Sun, L W; Zhang, H Y; Wu, L; Shu, S; Xia, C; Xu, C; Zheng, J S

    2014-03-01

    The purpose of this study was to assess the metabolic profile of plasma samples from cows with clinical and subclinical ketosis. According to clinical signs and 3-hydroxybutyrate plasma levels, 81 multiparous Holstein cows were selected from a dairy farm 7 to 21 d after calving. The cows were divided into 3 groups: cows with clinical ketosis, cows with subclinical ketosis, and healthy control cows. (1)H-Nuclear magnetic resonance-based metabolomics was used to assess the plasma metabolic profiles of the 3 groups. The data were analyzed by principal component analysis, partial least squares discriminant analysis, and orthogonal partial least-squares discriminant analysis. The differences in metabolites among the 3 groups were assessed. The orthogonal partial least-squares discriminant analysis model differentiated the 3 groups of plasma samples. The model predicted clinical ketosis with a sensitivity of 100% and a specificity of 100%. In the case of subclinical ketosis, the model had a sensitivity of 97.0% and specificity of 95.7%. Twenty-five metabolites, including acetoacetate, acetone, lactate, glucose, choline, glutamic acid, and glutamine, were different among the 3 groups. Among the 25 metabolites, 4 were upregulated, 7 were downregulated, and 14 were both upregulated and downregulated. The results indicated that plasma (1)H-nuclear magnetic resonance-based metabolomics, coupled with pattern recognition analytical methods, not only has the sensitivity and specificity to distinguish cows with clinical and subclinical ketosis from healthy controls, but also has the potential to be developed into a clinically useful diagnostic tool that could contribute to a further understanding of the disease mechanisms. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  16. Advanced Nuclear Magnetic Resonance

    OpenAIRE

    Alonso, Diego A.

    2014-01-01

    Transparencias en inglés de la asignatura "Resonancia Magnética Nuclear Avanzada" (Advanced Nuclear Magnetic Resonance) (36643) que se imparte en el Máster de Química Médica como asignatura optativa de 3 créditos ECTS. En esta asignatura se completa el estudio iniciado en la asignatura de quinto curso de la licenciatura en Química "Determinación estructural" (7448) y en la del Grado de Química de tercer curso "Determinación estructural de los compuestos orgánicos" (26030) en lo referente a té...

  17. Cranial magnetic resonance imaging

    International Nuclear Information System (INIS)

    Elster, A.D.

    1988-01-01

    Cranial Magnetic Resonance Imaging is comprehensive, well structured, and well written. The material is current and well referenced. The illustrations are good and complement the text well. The overall quality of publication is above average. The greatest attribute of the book is its readability. The author demonstrates ample skill in making complex subjects, such as MR physics and imaging of cerebral hemorrhage, easy to understand. The book closes with a detailed atlas on the anatomic appearance of the brain on MR images in the axial, coronal, and sagittal planes

  18. Nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Cremin, B.J.

    1981-01-01

    Recent advances in diagnostic imaging, have been the medical application of nuclear magnetic resonance (NMR). It's been used to study the structure of various compounds in chemistry and physics, and in the mid-1970 to produce images of rabbits and eventually of the human hand and head. The images are produced by making use of the nuclear magnetization of the hydrogen ion, or proton, that is present in biological material to record the density distribution of protons in cellular water and lipids. An exploration of the end-results of complicated free induction decay signals, that have been digitized and frequency-analysed by mathematical computerized techniques to produce an image of tissue density, is given. At present NMR produces images comparable to those of early computed tomography

  19. [Clinical application of proton magnetic resonance spectroscopy in children with idiopathic epilepsy].

    Science.gov (United States)

    Shao, Xiao-Li; Zhou, Zhong-Shu; Hong, Wen

    2010-06-01

    This study examined the biochemical metabolism by proton magnetic resonance spectroscopy ('H-MRS) in order to explore the value of 'H-MRS in idiopathic epilepsy in children. Thirty-three children with idiopathic epilepsy (14 cases with history of febrile seizures and 19 cases without) and six normal controls experienced MRI of the skull and brain and single-voxel 'H-MRS examinations of the hippocampi-temporal lobe. The signal intensities of N-acetylaspartate (NAA), eatine+phosphocreatine (Cr), choline-containing compounds (Cho) and lactate (Lac) and the ratios of NAA/ (Cho+Cr) and Lac/Cr were compared between the patients and normal controls. MRI examination showed that only one child with epilepsy had myelin dysplasia. 'H-MRS examination showed that the ratio of NAA/ (Cho+Cr) in the epilepsy group was lower than that in the control group (0.64+/-0.07 vs 0.73+/-0.05; Pepilepsy and the control groups. 'H-MRS may provide early information on brain injury sensitively and non-invasively in children with epilepsy. It may be used for diagnosis and prognosis evaluation of epilepsy.

  20. Magnetic resonance imaging of clinically stable late pregnancy bleeding: beyond ultrasound

    Energy Technology Data Exchange (ETDEWEB)

    Masselli, Gabriele; Gualdi, Gianfranco [Sapienza University, Radiology Dea Department, Umberto I Hospital, Rome (Italy); Brunelli, Roberto; Perrone, Giuseppina [Sapienza University, Department of Gynecology and Obstetrics, Umberto I Hospital, Rome (Italy); Parasassi, Tiziana [Institute of Neurobiology and Molecular Medicine, National Research Council, Rome (Italy)

    2011-09-15

    To compare the accuracy of magnetic resonance (MRI) and colour Doppler-ultrasound (US) in the diagnosis of late pregnancy bleeding and to assess the accuracy of the different MR sequences in visualizing the origin of haemorrhage. 42 patients in the third trimester of pregnancy underwent to US and MRI for the evaluation of painless vaginal bleeding. Multiplanar HASTE, True Fisp, 3D T1 GRE and sagittal DWI sequences were acquired. Two radiologists, blinded to the results of US, reviewed each case, resolving by consensus any discrepancy. Reference standards were surgical and pathological findings. The reference standards identified 22 placenta previa, 11 placental abruptions (1 coincident with a placental chorioangioma), 1 thrombohaematoma and 1 fibroma with haemorrhagic degeneration. MRI identified correctly all these condition with an interobserver agreement of 0.955. DWI and T1 weighted sequences were statistically superior to Haste and True Fisp sequences in detecting the cause of bleeding (p <.001). US had 6 false negatives and 2 false positive results, its diagnostic accuracy resulting lower than MRI (p =.001). MRI accurately evaluates pregnancy bleeding with an excellent interobserver agreement and can grant new and additional data when US is negative. (orig.)

  1. Magnetic resonance imaging of clinically stable late pregnancy bleeding: beyond ultrasound

    International Nuclear Information System (INIS)

    Masselli, Gabriele; Gualdi, Gianfranco; Brunelli, Roberto; Perrone, Giuseppina; Parasassi, Tiziana

    2011-01-01

    To compare the accuracy of magnetic resonance (MRI) and colour Doppler-ultrasound (US) in the diagnosis of late pregnancy bleeding and to assess the accuracy of the different MR sequences in visualizing the origin of haemorrhage. 42 patients in the third trimester of pregnancy underwent to US and MRI for the evaluation of painless vaginal bleeding. Multiplanar HASTE, True Fisp, 3D T1 GRE and sagittal DWI sequences were acquired. Two radiologists, blinded to the results of US, reviewed each case, resolving by consensus any discrepancy. Reference standards were surgical and pathological findings. The reference standards identified 22 placenta previa, 11 placental abruptions (1 coincident with a placental chorioangioma), 1 thrombohaematoma and 1 fibroma with haemorrhagic degeneration. MRI identified correctly all these condition with an interobserver agreement of 0.955. DWI and T1 weighted sequences were statistically superior to Haste and True Fisp sequences in detecting the cause of bleeding (p <.001). US had 6 false negatives and 2 false positive results, its diagnostic accuracy resulting lower than MRI (p =.001). MRI accurately evaluates pregnancy bleeding with an excellent interobserver agreement and can grant new and additional data when US is negative. (orig.)

  2. Clinical role of secretin loading magnetic resonance cholangiopancreatography in the patients undergoing pancreatic resection

    Energy Technology Data Exchange (ETDEWEB)

    Shimada, Ken; Takahashi, Tsuyoshi; Yoshida, Muneki; Kakita, Akira [Kitasato Univ., Sagamihara, Kanagawa (Japan). School of Medicine

    2002-01-01

    We determined factors contributing to increased signal intensity in the reconstructed jejunal loop in patients undergoing pancreatic resection, frequently observed on magnetic resonance cholangiopancreatography following intravenous injection of secretin (S/MRCP). We also evaluated the possible roles of S/MRCP in assessing the patency of pancreatojejunal anastomosis and the secretory function of the remnant pancreas. Subject were 44 patients undergoing several types of pancreatic resection. Baseline output and response to secretin of the remnant pancreas were measured after surgery. S/MRCP and pancreatic function diagnostant (PFD) tests were conducted preoperatively, and in early and late periods after surgery. Baseline pancreatic output was 1.2{+-}0.7 ml/10-min, and increased after secretin load to a maximum 9.0{+-}6.6 ml/10-min in 10 min. Signal intensity of the jejunal loop increased in 2 patients versus 40 patients (95%) during the early versus late postoperative periods. During the late period, PFD was significantly higher in patients with increased signal intensity than in those without. PFD correlated well with cumulative pancreatic output following secretin loading (r=0.820). A major factor responsible for increased signal intensity in S/MRCP of the jejunal loop was increased pancreatic output. The increase in signal intensity was a definitive sign of patent pancreatojejunal anastomosis. S/MRCP thus seems to have a potential for evaluating the secretory function of the remnant pancreas. (author)

  3. Clinical role of secretin loading magnetic resonance cholangiopancreatography in the patients undergoing pancreatic resection

    International Nuclear Information System (INIS)

    Shimada, Ken; Takahashi, Tsuyoshi; Yoshida, Muneki; Kakita, Akira

    2002-01-01

    We determined factors contributing to increased signal intensity in the reconstructed jejunal loop in patients undergoing pancreatic resection, frequently observed on magnetic resonance cholangiopancreatography following intravenous injection of secretin (S/MRCP). We also evaluated the possible roles of S/MRCP in assessing the patency of pancreatojejunal anastomosis and the secretory function of the remnant pancreas. Subject were 44 patients undergoing several types of pancreatic resection. Baseline output and response to secretin of the remnant pancreas were measured after surgery. S/MRCP and pancreatic function diagnostant (PFD) tests were conducted preoperatively, and in early and late periods after surgery. Baseline pancreatic output was 1.2±0.7 ml/10-min, and increased after secretin load to a maximum 9.0±6.6 ml/10-min in 10 min. Signal intensity of the jejunal loop increased in 2 patients versus 40 patients (95%) during the early versus late postoperative periods. During the late period, PFD was significantly higher in patients with increased signal intensity than in those without. PFD correlated well with cumulative pancreatic output following secretin loading (r=0.820). A major factor responsible for increased signal intensity in S/MRCP of the jejunal loop was increased pancreatic output. The increase in signal intensity was a definitive sign of patent pancreatojejunal anastomosis. S/MRCP thus seems to have a potential for evaluating the secretory function of the remnant pancreas. (author)

  4. Assessment of Bladder Motion for Clinical Radiotherapy Practice Using Cine-Magnetic Resonance Imaging

    International Nuclear Information System (INIS)

    McBain, Catherine A.; Khoo, Vincent S.; Buckley, David L.; Sykes, Jonathan S.; Green, Melanie M.; Cowan, Richard A.; Hutchinson, Charles E.; Moore, Christopher J.; Price, Patricia M.

    2009-01-01

    Purpose: Organ motion is recognized as the principal source of inaccuracy in bladder radiotherapy (RT), but there is currently little information on intrafraction bladder motion. Methods and Materials: We used cine-magnetic resonance imaging (cine-MRI) to study bladder motion relevant to intrafraction RT delivery. On two occasions, a 28 minute cine-MRI sequence was acquired from 10 bladder cancer patients and 5 control participants immediately after bladder emptying, after abstinence from drinking for the preceding hour. From the resulting cine sequences, bladder motion was subjectively assessed. To quantify bladder motion, the bladder was contoured in imaging volume sets at 0, 14, and 28 min to measure changes to bladder volumes, wall displacements, and center of gravity (COG) over time. Results: The dominant source of bladder motion during imaging was bladder filling (up to 101% volume increase); rectal and small bowel movements were transient, with minimal impact. Bladder volume changes were similar for all participants. However for bladder cancer patients, wall displacements were larger (up to 58 mm), less symmetrical, and more variable compared with nondiseased control bladders. Conclusions: Significant and individualized intrafraction bladder wall displacements may occur during bladder RT delivery. This important source of inaccuracy should be incorporated into treatment planning and verification.

  5. Advances in magnetic resonance 11

    CERN Document Server

    Waugh, John S

    2013-01-01

    Advances in Magnetic Resonance, Volume 11, presents a variety of contributions to the theory and practice of magnetic resonance. The book contains three chapters and begins with a discussion of the principles and applications of dynamic nuclear polarization, with emphasis on molecular motions and collisions, intermolecular couplings, and chemical interactions. Subsequent chapters focus on the assessment of a proposed broadband decoupling method and studies of time-domain (or Fourier transform) multiple-quantum nuclear magnetic resonance.

  6. Clinical utility of magnetic resonance imaging and ultrasonography for diagnosis of polycystic ovary syndrome in adolescent girls.

    Science.gov (United States)

    Kenigsberg, Lisa E; Agarwal, Chhavi; Sin, Sanghun; Shifteh, Keivan; Isasi, Carmen R; Crespi, Rebecca; Ivanova, Janeta; Coupey, Susan M; Heptulla, Rubina A; Arens, Raanan

    2015-11-01

    To evaluate ovarian morphology using three-dimensional magnetic resonance imaging (MRI) in adolescent girls with and without polycystic ovary syndrome (PCOS). Also compare the utility of MRI versus ultrasonography (US) for diagnosis of PCOS. Cross-sectional study. Urban academic tertiary-care children's hospital. Thirty-nine adolescent girls with untreated PCOS and 22 age/body mass index (BMI)-matched controls. Magnetic resonance imaging and/or transvaginal/transabdominal US. Ovarian volume (OV); follicle number per section (FNPS); correlation between OV on MRI and US; proportion of subjects with features of polycystic ovaries (PCOs) on MRI and US. Magnetic resonance imaging demonstrated larger OV and higher FNPS in subjects with PCOS compared with controls. Within the PCOS group, median OV was 11.9 (7.7) cm(3) by MRI compared with 8.8 (7.8) cm(3) by US. Correlation coefficient between OV by MRI and US was 0.701. Due to poor resolution, FNPS could not be determined by US or compared with MRI. The receiver operating characteristic curve analysis for MRI demonstrated that increasing volume cutoffs for PCOs from 10-14 cm(3) increased specificity from 77%-95%. For FNPS on MRI, specificity increased from 82%-98% by increasing cutoffs from ≥ 12 to ≥ 17. Using Rotterdam cutoffs, 91% of subjects with PCOS met PCO criteria on MRI, whereas only 52% met criteria by US. Ultrasonography measures smaller OV than MRI, cannot accurately detect follicle number, and is a poor imaging modality for characterizing PCOs in adolescents with suspected PCOS. For adolescents in whom diagnosis of PCOS remains uncertain after clinical and laboratory evaluation, MRI should be considered as a diagnostic imaging modality. Copyright © 2015 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  7. Nuclear magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Rabenstein, D.L.; Guo, W.

    1988-01-01

    Nuclear magnetic resonance (NMR) spectroscopy is one of the most widely used instrumental methods, with applications ranging from the characterization of pure compounds by high-resolution NMR to the diagnosis of disease by magnetic resonance imaging (MRI). To give some idea of the wide-spread use of NMR, a computer search for the period 1985-1987 turned up over 500 books and review articles and over 7000 literature citations, not including papers in which NMR was used together with other spectroscopic methods for the routine identification of organic compounds. Consequently, they have by necessity been somewhat selective in the topics they have chosen to cover and in the articles they have cited. In this review, which covers the published literature for the approximate period Sept 1985-Aug 1987, they have focused on new developments and applications of interest to the chemist. First they review recent developments in instrumentation and techniques. Although there have not been any major break-throughs in NMR instrumentation during the past two years, significant refinements have been reported which optimize instrumentation for the demanding multiple pulse experiments in routine use today. Next they review new developments in methods for processing NMR data, followed by reviews of one-dimensional and two-dimensional NMR experiments

  8. Advances in magnetic resonance 6

    CERN Document Server

    Waugh, John S

    2013-01-01

    Advances in Magnetic Resonance, Volume 6 focuses on the theoretical and practical aspects of applying magnetic resonance methods to various problems in physical chemistry, emphasizing the different aspects of the exegesis of these problems. This book discusses the gas phase magnetic resonance of electronically excited molecules; techniques for observing excited electronic states; NMR studies in liquids at high pressure; and effect of pressure on self-diffusion in liquids. The nuclear magnetic resonance investigations of organic free radicals; measurement of proton coupling constants by NMR; an

  9. Disc pathology after whiplash injury. A prospective magnetic resonance imaging and clinical investigation; Pathologie vertebrale apres le coup du lapin. Une investigation clinique et d` imagerie prospective par resonance magnetique

    Energy Technology Data Exchange (ETDEWEB)

    Pettersson, K.; Hildingsson, C.; Toolanen, G.; Fagerlund, M.; Bjornebrink, J. [University Hospital of Northem (Sweden)

    1997-09-01

    Although disc pathology seems to be one contributing factor in the development of chronic symptoms after whiplash injury, it may be unnecessary to examine these patients in the acute phase with magnetic resonance imaging ; correlating initial symptoms and signs to magnetic resonance imaging findings is difficult because of the relatively high proportion of false-positive results. Magnetic resonance imaging is indicated later in the course of treatment in patients with persistent arm pain, neurologic deficits, or clinical signs of nerve root compression to diagnose disc herniations requiring surgery. (authors).

  10. Children's (Pediatric) Magnetic Resonance Imaging

    Medline Plus

    Full Text Available ... immediately after the exam. A few patients experience side effects from the contrast material, including nausea and local ... Related Articles and Media Catheter Angiography Magnetic Resonance, Functional (fMRI) - Brain Children's (Pediatric) CT (Computed Tomography) Magnetic ...

  11. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    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 ...

  12. Children's (Pediatric) Magnetic Resonance Imaging

    Medline Plus

    Full Text Available ... Related Articles and Media Catheter Angiography Magnetic Resonance, Functional (fMRI) - Brain Children's (Pediatric) CT (Computed Tomography) Magnetic ... the possible charges you will incur. Web page review process: This Web page is reviewed regularly by ...

  13. Collagene order of articular cartilage by clinical magnetic resonance images and its age dependency

    Energy Technology Data Exchange (ETDEWEB)

    Seidel, P.; Gruender, W. [Inst. of Medical Physics and Biophysics, Univ. of Leipzig (Germany)

    2005-07-01

    The present papers describes a novel method to obtain information on the degree of order of the collagen network of the knee meniscal cartilage by means of a single clinical MRI. Images were obtained from 34 healthy volunteers aged between 6 and 76 years as well as from one patient with clinically-diagnosed arthrosis at the age of 32 and 37 years. A siemens vision (1.5 T) MRT with TR = 750 ms, TE = 50 ms, FoV = 160 mm, and Matrix 512 x 512 was used for this purpose. The MR signal intensities of the cartilage were read out along slices with constant height above the subchondral bone and plotted versus the actual angle to the external magnetic field. The obtained intensity curves were fitted by a model distribution, and the degree of order of the collagen fibers was calculated. For the knee meniscal cartilage, there was an age-dependency of the degree of order and a significant deviation of the volunteer with arthrosis from the normal curve. The results are discussed in view of the arcade model and of a possible use of non-invasive clinical MRT for the detection of early arthrotic changes of cartilage. (orig.)

  14. Clinical significance of periventricular high intensity lesions on magnetic resonance imaging in dementia

    International Nuclear Information System (INIS)

    Kaieda, Makoto

    1991-01-01

    In this study, vascular dementia (VD, 31 cases), senile dementia of Alzheimer type (DAT, 36 cases) and mixed type dementia (14 cases) were studied by means of magnetic resonance imaging (MRI). Diagnosis of dementia was made according to DSM-III and Hachinski's ischemic score. The areas of periventricular high intensity lesions (PVH) and those of brain parenchyma were measured by digitizer which was connected to a computer. The PVH score was obtained by dividing the areas of PVH by those of brain parenchyma at the level of the body of the lateral ventricle. A multiple variable analysis was applied to the PVH scores and risk factors for dementia using Hayashi's quantification method I. The multiple correlation coefficient between the PVH and the risk factors was 0.685. The most significant correlation was found between Hachinski's ischemic score and the PVH score (partial correlation coefficient: 0.58). Significant correlations were also found between ADL and the PVH score (0.25), as well as between the Hasegawa dementia score and the PVH score (0.24). Using the student T test, it was shown that the large PVH group was significantly correlated to poor ADL, whereas the small PVH group was not. The large PVH group in VD showed lower Hasegawa score than the small PVH group. On the other hand, there was no such correlation in DAT. PVH with prolongation of T2 could exist in various pathological states irrespective of their causes. Diffuse PVH tended to be frequently observed in VD together with poor ADL. It was therefore thought that brain ischemia was the main cause of PVH. (author)

  15. Clinical significance of periventricular high intensity lesions on magnetic resonance imaging in dementia

    Energy Technology Data Exchange (ETDEWEB)

    Kaieda, Makoto [Nippon Medical School, Tokyo (Japan)

    1991-04-01

    In this study, vascular dementia (VD, 31 cases), senile dementia of Alzheimer type (DAT, 36 cases) and mixed type dementia (14 cases) were studied by means of magnetic resonance imaging (MRI). Diagnosis of dementia was made according to DSM-III and Hachinski's ischemic score. The areas of periventricular high intensity lesions (PVH) and those of brain parenchyma were measured by digitizer which was connected to a computer. The PVH score was obtained by dividing the areas of PVH by those of brain parenchyma at the level of the body of the lateral ventricle. A multiple variable analysis was applied to the PVH scores and risk factors for dementia using Hayashi's quantification method I. The multiple correlation coefficient between the PVH and the risk factors was 0.685. The most significant correlation was found between Hachinski's ischemic score and the PVH score (partial correlation coefficient: 0.58). Significant correlations were also found between ADL and the PVH score (0.25), as well as between the Hasegawa dementia score and the PVH score (0.24). Using the student T test, it was shown that the large PVH group was significantly correlated to poor ADL, whereas the small PVH group was not. The large PVH group in VD showed lower Hasegawa score than the small PVH group. On the other hand, there was no such correlation in DAT. PVH with prolongation of T2 could exist in various pathological states irrespective of their causes. Diffuse PVH tended to be frequently observed in VD together with poor ADL. It was therefore thought that brain ischemia was the main cause of PVH. (author).

  16. Magnetic resonance imaging-guided focused ultrasound ablation of uterine fibroids. Early clinical experience

    International Nuclear Information System (INIS)

    Mikami, Koji; Osuga, Keigo; Tomoda, Kaname; Nakamura, Hironobu; Murakami, Takamichi; Okada, Atsuya

    2008-01-01

    The aim of this study was to assess the feasibility and effectiveness of magnetic resonance (MRI)-guided focused ultrasound (MRIgFUS) ablation for uterine fibroids and to identify the candidates for this treatment. A total of 48 patients with a symptomatic uterine fibroid underwent MRIgFUS. The percent ablation volume was calculated, and the patients' characteristics and the MR imaging features of the fibroids that might predict the effect of this treatment were assessed. Changes in the symptoms related to the uterine fibroid were assessed at 6 and 12 months. The planned target zone were successfully treated in 32 patients with bulk-related and menstrual symptoms but unsuccessfully treated in the remaining 16 patients. These 16 patients were obese or their uterine fibroid showed heterogeneous high signal intensity on T2-weighted images. The 32 successfully treated patients were followed up for 6 months. At the 6-month follow-up, bulk-related and menstrual symptoms were diminished in 60% and 51% of patients, respectively. Among them, 17 patients were followed up for 12 months, and 9 of them who showed alleviation of bulk-related symptoms at 6 months had further improvement. The mean percent ablation volume of those nine patients was 51%. In 5 (33%) of the 15 patients with alleviation of menstrual symptoms at 6 months, the symptoms became worse at 12 months. There was a significant difference in the mean percent ablation volume between patients with alleviation of menstrual symptoms and those without (54% vs. 37%; P=0.03). MRIgFUS ablation is a safe, effective treatment for nonobese patients with symptomatic fibroids that show low signal intensity on T2-weighted images. Ablation of more than 50% of the fibroid volume may be needed with a short-term follow-up. (author)

  17. Clinical application of nuclear magnetic resonance imaging (resistive type) on cardiovascular disease

    International Nuclear Information System (INIS)

    Imai, Hitoshi; Yoshida, Katsuya; Watanabe, Shigeru; Masuda, Yoshiaki; Inagaki, Yoshiaki; Ikehira, Hiroo; Fukuda, Nobuo; Tateno, Yukio.

    1984-01-01

    In order to evaluate the usefulness of Nuclear Magnetic Resonance (NMR) imaging in diagnosing cardiovascular disease, 27 subjects were examined using a 0.1-Tesla resistive type (ASAHI MARK-J). In 10 normal subjects, four cardiac chambers, interventricular septum, aorta, pulmonary vessels and vena cava were clearly identified in NMR imaging. In two patients with old anteroseptal myocardial infarction, anteroseptal wall thinning and left ventricular aneurysm with mural thrombi were demonstrated. In two cases of antrolateral and posterolateral myocardial infarction, however, infarcted areas were not identified in NMR imaging. In one patient with congestive cardiomyopathy, enlarged left ventricle without hypertrophy was recognized. In two patients with hypertrophic obstructive cardiomyopathy, NMR imaging disclosed thickened left ventricular wall associated with its narrowed cavity. A mural thrombus in the right ventricle was distinctly visualized in one patient with cardio-vascular Behcet's disease. In two patients with mitral valve stenosis, enlarged left atrium with a mural thrombus was clearly demonstrated in both cross and longitudinal sections. In three patients with thoratic aortic aneurysm, local dilatation of aorta and mural thrombi were recognized. In four patients with dissecting aortic aneurysm, double channels with an intimal flap in the aorta were visualized in NMR imaging. Mean T 1 values and standard deviations of left ventricle, left ventricular wall, and thrombi were 593+-89, 341+-20, 316+-84 msec, respectively. Mean T 1 values of thrombi were ordinally shorter than those of left ventricule. But some thrombi which might be expected fresh had longer T 1 values. (J.P.N.)

  18. Cardiovascular magnetic resonance in congenital heart disease

    International Nuclear Information System (INIS)

    Cazacu, A.; Ciubotaru, A.

    2010-01-01

    The increasing prevalence of congenital heart disease can be attributed to major improvements in diagnosis and treatment. Cardiovascular magnetic resonance imaging plays an important role in the clinical management strategy of patients with congenital heart disease. The development of new cardiovascular magnetic resonance (CMR) techniques allows comprehensive assessment of complex cardiac anatomy and function and provides information about the long-term residual post-operative lesions and complications of surgery. It overcomes many of the limitations of echocardiography and cardiac catheterization. This review evaluates the role of cardiovascular magnetic resonance imaging modality in the management of subject with congenital heart disease (CHD). (authors)

  19. Functional magnetic resonance imaging by visual stimulation

    International Nuclear Information System (INIS)

    Nishimura, Yukiko; Negoro, Kiyoshi; Morimatsu, Mitsunori; Hashida, Masahiro

    1996-01-01

    We evaluated functional magnetic resonance images obtained in 8 healthy subjects in response to visual stimulation using a conventional clinical magnetic resonance imaging system with multi-slice spin-echo echo planar imaging. Activation in the visual cortex was clearly demonstrated by the multi-slice experiment with a task-related change in signal intensity. In addition to the primary visual cortex, other areas were also activated by a complicated visual task. Multi-slice spin-echo echo planar imaging offers high temporal resolution and allows the three-dimensional analysis of brain function. Functional magnetic resonance imaging provides a useful noninvasive method of mapping brain function. (author)

  20. Magnetic resonance imaging of the coronary arteries : clinical results from three dimensional evaluation of a respiratory gated technique

    NARCIS (Netherlands)

    van Geuns, R J; de Bruin, H G; Rensing, B J; Wielopolski, P A; Hulshoff, M D; van Ooijen, P M; Oudkerk, M; de Feyter, P J

    1999-01-01

    BACKGROUND: Magnetic resonance coronary angiography is challenging because of the motion of the vessels during cardiac contraction and respiration. Additional challenges are the small calibre of the arteries and their complex three dimensional course. Respiratory gating, turboflash acquisition, and

  1. Magnetic resonance imaging of the coronary arteries: clinical results from three dimensional evaluation of a respiratory gated technique

    NARCIS (Netherlands)

    R.J.M. van Geuns (Robert Jan); H.G. de Bruin (Hein); B.J.W.M. Rensing (Benno); P.A. Wielopolski (Piotr); M.D. Hulshoff; P.M.A. van Ooijen (Peter); M. Oudkerk (Matthijs); P.J. de Feyter (Pim)

    1999-01-01

    textabstractBACKGROUND: Magnetic resonance coronary angiography is challenging because of the motion of the vessels during cardiac contraction and respiration. Additional challenges are the small calibre of the arteries and their complex three dimensional course. Respiratory

  2. Cine magnetic resonance

    International Nuclear Information System (INIS)

    Higgins, C.B.; Sechtem, U.P.; Pflugfelder, P.

    1987-01-01

    Cine magnetic resonance (MR) is a fast MR imaging process with referencing of the imaging data to the electrocardiogram (ECG) so that images corresponding to 21-msec segments of the cardiac cycle are acquired. A series of such images, each corresponding to a 21-msec segment of the cardiac cycle, can be laced together for viewing in the cine format at a framing rate of 20 to 40 frames per second. Since cine angiograms of the heart are usually done at 30 frames per second, this technique achieves a temporal resolution adequate for the evluation of central cardiovascular function. The major application of this technique is to depict central cardiovascular function and blood flow

  3. Children's (Pediatric) Magnetic Resonance Imaging

    Medline Plus

    Full Text Available ... Resources Professions Site Index A-Z Children’s (Pediatric) Magnetic Resonance Imaging Children’s magnetic resonance imaging (MRI) uses a powerful ... for an MRI exam contains a metal called gadolinium . Gadolinium can be used in patients with iodine ...

  4. Children's (Pediatric) Magnetic Resonance Imaging

    Medline Plus

    Full Text Available ... work? Unlike conventional x-ray examinations and computed tomography (CT) scans, MRI does not utilize ionizing radiation. Instead, ... Angiography Magnetic Resonance, Functional (fMRI) - Brain Children's (Pediatric) CT (Computed Tomography) Magnetic Resonance Imaging (MRI) Safety Contrast Materials Children ...

  5. Children's (Pediatric) Magnetic Resonance Imaging

    Medline Plus

    Full Text Available ... Resources Professions Site Index A-Z Children’s (Pediatric) Magnetic Resonance Imaging Children’s magnetic resonance imaging (MRI) uses ... identify and accurately characterize diseases than other imaging methods. This detail makes MRI an invaluable tool in ...

  6. Can magnetic resonance imaging differentiate undifferentiated arthritis?

    DEFF Research Database (Denmark)

    Østergaard, Mikkel; Duer, Anne; Hørslev-Petersen, K

    2005-01-01

    A high sensitivity for the detection of inflammatory and destructive changes in inflammatory joint diseases makes magnetic resonance imaging potentially useful for assigning specific diagnoses, such as rheumatoid arthritis and psoriatic arthritis in arthritides, that remain undifferentiated after...... conventional clinical, biochemical and radiographic examinations. With recent data as the starting point, the present paper describes the current knowledge on magnetic resonance imaging in the differential diagnosis of undifferentiated arthritis....

  7. Magnetic resonance of low dimensional magnetic solids

    Energy Technology Data Exchange (ETDEWEB)

    Gatteschi, D.; Ferraro, F.; Sessoli, R. (Florence Univ. (Italy))

    1994-06-01

    The utility of EPR and NMR in the study of low-dimensional magnetic solids is shown. A short summary of the basis of magnetic resonance in these systems is reported, and the importance of spin-diffusion and magnetic anisotropy evidenced. Some results from experiments on metal-radical chains and clusters are presented. (authors). 37 refs., 7 figs.

  8. Magnetic resonance of low dimensional magnetic solids

    International Nuclear Information System (INIS)

    Gatteschi, D.; Ferraro, F.; Sessoli, R.

    1994-01-01

    The utility of EPR and NMR in the study of low-dimensional magnetic solids is shown. A short summary of the basis of magnetic resonance in these systems is reported, and the importance of spin-diffusion and magnetic anisotropy evidenced. Some results from experiments on metal-radical chains and clusters are presented. (authors). 37 refs., 7 figs

  9. Advances in magnetic resonance 12

    CERN Document Server

    Waugh, John S

    2013-01-01

    Advances in Magnetic Resonance, Volume 12, presents a variety of contributions to the theory and practice of magnetic resonance. The book contains six chapters and begins with a discussion of diffusion and self-diffusion measurements by nuclear magnetic resonance. This is followed by separate chapters on spin-lattice relaxation time in hydrogen isotope mixtures; the principles of optical detection of nuclear spin alignment and nuclear quadropole resonance; and the spin-1 behavior, including the relaxation of the quasi-invariants of the motion of a system of pairs of dipolar coupled spin-1/2 nu

  10. Analysis of clinical course and magnetic resonance imaging of posttraumatic diabetes insipidus

    International Nuclear Information System (INIS)

    Inoue, Yoshiaki; Hirota, Tetsuya; Kohno, Masanobu; Iwai, Atsushi; Abe, Yoshio; Ikeuchi, Hisashi; Yoshioka, Toshiharu

    2002-01-01

    We analyzed the relationship between posttraumatic diabetes insipidus (DI) onset and magnetic resonance imaging (MRI). In the last 5 years, 13 survivors of head injury were diagnosed with DI. We divided them into 2 groups, early and delayed, by DI onset. The early group consisted of 5 patients diagnosed with DI within 12 hours of injury. The delayed group consisted of 8 diagnosed after 12 hours or more. We analyzed differences between groups for factors such as Glasgow coma scale (GCS) on admission, Glasgow outcome scale (GOS) at discharge, DI duration, intracranial pressure (ICP) when diagnosed with DI, maximum ICP during observation, and MRI findings. In the early group, mean onset of DI was about 40 hours earlier than that in the delayed group, 7±2 vs. 47±19 hours, p<0.05. No significant differences were seen between groups for GCS, ISS, or GOS. Although no significant difference was seen in ICP, barbiturate therapy was needed in 7 cases, craniotomy in 4, and hypothermia therapy in 5 to control ICP in the delayed group. Barbiturate therapy was needed in only 2 cases and no indications were seen for craniotomy or hypothermia therapy in the early group. All cases in the delayed group recovered from DI within 3 weeks, but 3 in the early group were diagnosed with permanent DI and 1 needed antidiuretic hormone (ADH) during 75 days. All of the early group was recognized to have hypothalamic injury and diffuse axonal injury in MRI, but none in the delayed group was recognized for these MRI findings. In the delayed group, the high-intensity signal of the posterior pituitary gland in T1 weighted MRI, thought to represent the granule of ADH, disappeared in the early period and reappeared gradually after recovery from DI, but this signal did not reappear in the early group. We therefore conducted that the crucial cause of posttraumatic DI in the early group is direct hypothalamic injury, perhaps due to diffuse axonal injury, and that in the delayed group, secondary

  11. Analysis of clinical course and magnetic resonance imaging of posttraumatic diabetes insipidus

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, Yoshiaki; Hirota, Tetsuya; Kohno, Masanobu; Iwai, Atsushi; Abe, Yoshio; Ikeuchi, Hisashi; Yoshioka, Toshiharu [Osaka Prefectural General Hospital (Japan)

    2002-06-01

    We analyzed the relationship between posttraumatic diabetes insipidus (DI) onset and magnetic resonance imaging (MRI). In the last 5 years, 13 survivors of head injury were diagnosed with DI. We divided them into 2 groups, early and delayed, by DI onset. The early group consisted of 5 patients diagnosed with DI within 12 hours of injury. The delayed group consisted of 8 diagnosed after 12 hours or more. We analyzed differences between groups for factors such as Glasgow coma scale (GCS) on admission, Glasgow outcome scale (GOS) at discharge, DI duration, intracranial pressure (ICP) when diagnosed with DI, maximum ICP during observation, and MRI findings. In the early group, mean onset of DI was about 40 hours earlier than that in the delayed group, 7{+-}2 vs. 47{+-}19 hours, p<0.05. No significant differences were seen between groups for GCS, ISS, or GOS. Although no significant difference was seen in ICP, barbiturate therapy was needed in 7 cases, craniotomy in 4, and hypothermia therapy in 5 to control ICP in the delayed group. Barbiturate therapy was needed in only 2 cases and no indications were seen for craniotomy or hypothermia therapy in the early group. All cases in the delayed group recovered from DI within 3 weeks, but 3 in the early group were diagnosed with permanent DI and 1 needed antidiuretic hormone (ADH) during 75 days. All of the early group was recognized to have hypothalamic injury and diffuse axonal injury in MRI, but none in the delayed group was recognized for these MRI findings. In the delayed group, the high-intensity signal of the posterior pituitary gland in T1 weighted MRI, thought to represent the granule of ADH, disappeared in the early period and reappeared gradually after recovery from DI, but this signal did not reappear in the early group. We therefore conducted that the crucial cause of posttraumatic DI in the early group is direct hypothalamic injury, perhaps due to diffuse axonal injury, and that in the delayed group, secondary

  12. Cardiac Magnetic Resonance-Verified Myocardial Fibrosis in Chagas Disease: Clinical Correlates and Risk Stratification.

    Science.gov (United States)

    Uellendahl, Marly; Siqueira, Maria Eduarda Menezes de; Calado, Eveline Barros; Kalil-Filho, Roberto; Sobral, Dário; Ribeiro, Clébia; Oliveira, Wilson; Martins, Silvia; Narula, Jagat; Rochitte, Carlos Eduardo

    2016-11-01

    Chagas disease (CD) is an important cause of heart failure and mortality, mainly in Latin America. This study evaluated the morphological and functional characteristics of the heart as well the extent of myocardial fibrosis (MF) in patients with CD by cardiac magnetic resonance (CMR). The prognostic value of MF evaluated by myocardial-delayed enhancement (MDE) was compared with that via Rassi score. This study assessed 39 patients divided into 2 groups: 28 asymptomatic patients as indeterminate form group (IND); and symptomatic patients as Chagas Heart Disease (CHD) group. All patients underwent CMR using the techniques of cine-MRI and MDE, and the amount of MF was compared with the Rassi score. Regarding the morphological and functional analysis, significant differences were observed between both groups (p realce tardio miocárdico (RTM) foi comparado àquele do escore de Rassi. Avaliação de 39 pacientes divididos em 2 grupos: grupo 'forma indeterminada' (IND), 28 pacientes assintomáticos; e grupo 'cardiopatia chagásica' (CC), pacientes sintomáticos. Todos os pacientes foram submetidos a RMC com as técnicas de cine-RM e RTM, sendo a quantidade de FM evidenciada ao exame comparada ao escore de Rassi. As análises morfológica e funcional mostraram significativas diferenças entre os 2 grupos (p < 0,001). Houve ainda uma forte correlação entre a extensão da FM e o escore de Rassi (r = 0,76). A RMC é uma importante técnica para avaliar pacientes com DC, ressaltando as diferenças morfológicas e funcionais em todas as apresentações clínicas. A forte correlação entre o escore de Rassi e a extensão da FM detectada por RMC enfatiza seu papel na estratificação prognóstica de pacientes com DC.

  13. Magnetic resonance imaging methodology

    International Nuclear Information System (INIS)

    Moser, Ewald; Stadlbauer, Andreas; Windischberger, Christian; Quick, Harald H.; Ladd, Mark E.

    2009-01-01

    Magnetic resonance (MR) methods are non-invasive techniques to provide detailed, multi-parametric information on human anatomy, function and metabolism. Sensitivity, specificity, spatial and temporal resolution may, however, vary depending on hardware (e.g., field strength, gradient strength and speed) and software (optimised measurement protocols and parameters for the various techniques). Furthermore, multi-modality imaging may enhance specificity to better characterise complex disease patterns. Positron emission tomography (PET) is an interesting, largely complementary modality, which might be combined with MR. Despite obvious advantages, combining these rather different physical methods may also pose challenging problems. At this early stage, it seems that PET quality may be preserved in the magnetic field and, if an adequate detector material is used for the PET, MR sensitivity should not be significantly degraded. Again, this may vary for the different MR techniques, whereby functional and metabolic MR is more susceptible than standard anatomical imaging. Here we provide a short introduction to MR basics and MR techniques, also discussing advantages, artefacts and problems when MR hardware and PET detectors are combined. In addition to references for more detailed descriptions of MR fundamentals and applications, we provide an early outlook on this novel and exciting multi-modality approach to PET/MR. (orig.)

  14. Clinical applications of proton magnetic resonance spectroscopy of the brain; Klinische Anwendungen der Protonen-Magnetresonanzspektroskopie des Gehirns

    Energy Technology Data Exchange (ETDEWEB)

    Laubenberger, J.; Bayer, S.; Thiel, T.; Hennig, J.; Langer, M. [Radiologische Universitaetsklinik Freiburg (Germany). Abt. Roentgendiagnostik

    1998-06-01

    In spite of all the scientific advances of the past few years, proton magnetic resonance spectroscopy of the brain has not attained the status of a routine examination technique with clinically accepted indications. The method should be considered as an additional option to MR imaging for inherited and acquired encephalopathic changes as well as, in future, for localization diagnosis of epilepsies. A proton magnetic resonance spectroscopic investigation without a prior intensive clinical and imaging investigation is not useful. Above all, factors influencing metabolite distribution such as for example, serum osmolability must be known. Methodological prerequisites for the clinical application of proton resonance spectroscopy are, first of all, a high stability of the chosen technique as well as a sufficiently certain quantification of metabolites and the availability of a reference group. The use of short echo times is necessary for the quantification of glutamine and the osmolyte myo-inositol. Indications for individual cases in which clinical investigations and MR topography cannot provide sufficient certainty and spectroscopy can furnish additional information are, in addition to uses in neuropediatrics, the suspicion of Alzheimer`s dementia, HIV encephalopathy in early manifestations, and unclarified depressions of consciousness accompanying liver cirrhosis. (orig.) [Deutsch] Die Protonen-Magnetresonanzspektroskopie des Gehirns ist trotz aller wissenschaftlicher Fortschritte der letzten Jahre noch nicht zu einer Routineuntersuchung mit anerkannter klinischer Indikationsstellung geworden. Die Untersuchung muss bei angeborenen und erworbenen enzephalopathischen Veraenderungen sowie in Zukunft in der Lokalisationsdiagnostik von Epilepsien als Zusatzoption zur MR-Bildgebung erachtet werden. Eine protonenspektroskopische Untersuchung ohne ausgiebige klinische und bildgebende Basisuntersuchung ist nicht sinnvoll. Insbesondere muessen Einflussfaktoren, wie z

  15. Magnetic resonance imaging for assessing hamstring injuries: clinical benefits and pitfalls – a review of the current literature

    Directory of Open Access Journals (Sweden)

    Greenky M

    2017-07-01

    Full Text Available Max Greenky, Steven B Cohen Department of Orthopedic Surgery, Rothman Institute, Thomas Jefferson University, Philadelphia, PA, USA Abstract: Hamstring injuries are common injuries in all levels of athletics. Hamstring injuries can cause prolonged absence from sports and have a notorious rate of reinjury. Magnetic resonance imaging (MRI is being increasingly utilized following a hamstring injury. Physicians are being increasingly asked to utilize MRI to predict clinical outcomes, including time frame for return to play and risk of reinjury. In spite of numerous studies in this area, no clear consensus exists. The purpose of this paper is to summarize the literature and evidence regarding the role of MRI in treating hamstring injuries. Keywords: hamstring injury, MRI, return to play

  16. Potential clinical applications of {sup 18}F-fluorodeoxyglucose position emission tomography/magnetic resonance mammography in breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Ihn Ho; Kong, Eun Jung [Dept. of Nuclear Medicine, Yeugnam University Hospital, Daegu (Korea, Republic of)

    2017-09-15

    The whole-body positron emission tomography (PET)/magnetic resonance (MR) scan is a cutting edge technology providing comprehensive structural information from MR imaging and functional features from PET in a single session. Recent research findings and clinical experience have shown that 18F-fluorodeoxyglucose (FDG) whole-body PET/MR imaging has a diagnostic performance comparable with or superior to that of PET/CT in the field of oncology, including for breast cancer. In particular, FDG PET/MR mammography in the prone position with the breast hanging in a pendant manner can provide more comprehensive information about the metabolism, anatomy, and functional features of a breast lesion than a whole-body PET/MR scan. This article reports on current state-of-the-art PET/MR mammography in patients with breast cancer and the prospects for potential application in the future.

  17. Musculoskeletal applications of magnetic resonance imaging: Council on Scientific Affairs

    International Nuclear Information System (INIS)

    Harms, S.E.; Fisher, C.F.; Fulmer, J.M.

    1989-01-01

    Magnetic resonance imaging provides superior contrast, resolution, and multiplanar imaging capability, allowing excellent definition of soft-tissue and bone marrow abnormalities. For these reasons, magnetic resonance imaging has become a major diagnostic imaging method for the evaluation of many musculoskeletal disorders. The applications of magnetic resonance imaging for musculoskeletal diagnosis are summarized and examples of common clinical situations are given. General guidelines are suggested for the musculoskeletal applications of magnetic resonance imaging

  18. Clinical value of proton magnetic resonance spectroscopy for differentiating recurrent or residual brain tumor from delayed cerebral necrosis

    International Nuclear Information System (INIS)

    Taylor, June S.; Langston, James W.; Reddick, Wilburn E.; Kingsley, Peter B.; Ogg, Robert J.; Pui, Margaret H.; Kun, Larry E.; Jenkins, Jesse J.; Gang, Chen; Ochs, Judith J.; Sanford, Robert A.; Heideman, Richard L.

    1996-01-01

    Purpose: Delayed cerebral necrosis (DN) is a significant risk for brain tumor patients treated with high-dose irradiation. Although differentiating DN from tumor progression is an important clinical question, the distinction cannot be made reliably by conventional imaging techniques. We undertook a pilot study to assess the ability of proton magnetic resonance spectroscopy ( 1 H MRS) to differentiate prospectively between DN or recurrent/residual tumor in a series of children treated for primary brain tumors with high-dose irradiation. Methods and Materials: Twelve children (ages 3-16 years), who had clinical and MR imaging (MRI) changes that suggested a diagnosis of either DN or progressive/recurrent brain tumor, underwent localized 1 H MRS prior to planned biopsy, resection, or other confirmatory histological procedure. Prospective 1 H MRS interpretations were based on comparison of spectral peak patterns and quantitative peak area values from normalized spectra: a marked depression of the intracellular metabolite peaks from choline, creatine, and N-acetyl compounds was hypothesized to indicate DN, and median-to-high choline with easily visible creatine metabolite peaks was labeled progressive/recurrent tumor. Subsequent histological studies identified the brain lesion as DN or recurrent/residual tumor. Results: The patient series included five cases of DN and seven recurrent/residual tumor cases, based on histology. The MRS criteria prospectively identified five out of seven patients with active tumor, and four out of five patients with histologically proven DN correctly. Discriminant analysis suggested that the primary diagnostic information for differentiating DN from tumor lay in the normalized MRS peak areas for choline and creatine compounds. Conclusions: Magnetic resonance spectroscopy shows promising sensitivity and selectivity for differentiating DN from recurrent/progressive brain tumor. A novel diagnostic index based on peak areas for choline and

  19. A Proton Magnetic Resonance Spectroscopic Study in Autism Spectrum Disorder Using a 3-Tesla Clinical Magnetic Resonance Imaging (MRI) System: The Anterior Cingulate Cortex and the Left Cerebellum.

    Science.gov (United States)

    Ito, Hiromichi; Mori, Kenji; Harada, Masafumi; Hisaoka, Sonoka; Toda, Yoshihiro; Mori, Tatsuo; Goji, Aya; Abe, Yoko; Miyazaki, Masahito; Kagami, Shoji

    2017-07-01

    The pathophysiology of autism spectrum disorder (ASD) is not fully understood. We used proton magnetic resonance spectroscopy to investigate metabolite concentration ratios in the anterior cingulate cortex and left cerebellum in ASD. In the ACC and left cerebellum studies, the ASD group and intelligence quotient- and age-matched control group consisted of 112 and 114 subjects and 65 and 45 subjects, respectively. In the ASD group, γ-aminobutyric acid (GABA)+/ creatine/phosphocreatine (Cr) was significantly decreased in the anterior cingulate cortex, and glutamate (Glu)/Cr was significantly increased and GABA+/Cr was significantly decreased in the left cerebellum compared to those in the control group. In addition, both groups showed negative correlations between Glu/Cr and GABA+/Cr in the left cerebellum, and positive correlations between GABA+/Cr in the anterior cingulate cortex and left cerebellum. ASD subjects have hypoGABAergic alterations in the anterior cingulate cortex and hyperglutamatergic/hypoGABAergic alterations in the left cerebellum.

  20. Study of correlation between clinical, magnetic resonance imaging, and arthroscopic findings in meniscal and anterior cruciate ligament injuries

    Directory of Open Access Journals (Sweden)

    Subhash R Puri

    2013-01-01

    Full Text Available Background: Approx. 28% of patients presents to orthopedic OPD with complaints of knee pain. Common medical complications include an unstable knee, chronic knee pain, and post traumatic arthritis. Aim: To study the correlation between clinical, magnetic resonance imaging (MRI, and arthroscopic findings in knee injuries. Materials and Methods: About 30 cases with history of rotational injury having knee pain and recurrent swelling were subjected to study. Results: MRI had better sensitivity (0.95 vs. 0.85 and specificity (1.0 vs. 0.5 in comparison with clinical examination for medial meniscus. In lateral meniscus injury (sensitivity 0.65 vs. 0.61 and specificity 0.95 vs. 0.92 and in ACL injury (Sensitivity 0.77 vs. 0.8 and specificity 1.0 vs. 0.96 the sensitivity and specificity of MRI versus clinical examination showed minimal difference. Conclusion: Our conclusion is that carefully performed clinical examination can give equal or better diagnosis of meniscal and ACL injuries in comparison with MRI scan. MRI may be used as an additional tool for diagnosis.

  1. Low field magnetic resonance imaging

    Science.gov (United States)

    Pines, Alexander; Sakellariou, Dimitrios; Meriles, Carlos A.; Trabesinger, Andreas H.

    2010-07-13

    A method and system of magnetic resonance imaging does not need a large homogenous field to truncate a gradient field. Spatial information is encoded into the spin magnetization by allowing the magnetization to evolve in a non-truncated gradient field and inducing a set of 180 degree rotations prior to signal acquisition.

  2. Cardiovascular Magnetic Resonance Imaging-Incremental Value in a Series of 361 Patients Demonstrating Cost Savings and Clinical Benefits: An Outcome-Based Study.

    Science.gov (United States)

    Hegde, Vinayak A; Biederman, Robert Ww; Mikolich, J Ronald

    2017-01-01

    This study was designed to assess the clinical impact and cost-benefit of cardiovascular magnetic resonance imaging (CMR). In the face of current health care cost concerns, cardiac imaging modalities have come under focused review. Data related to CMR clinical impact and cost-benefit are lacking. Retrospective review of 361 consecutive patients (pts) who underwent CMR exams was conducted. Indications for CMR were tabulated for appropriateness criteria. Components of the CMR exam were identified along with evidence of clinical impact. The cost of each CMR exam was ascertained along with cost savings attributable to the CMR exam for calculation of an incremental cost-effectiveness ratio. A total of 354 of 361 pts (98%) had diagnostic quality studies. Of the 361 pts, 350 (97%) had at least 1 published Appropriateness Criterion for CMR. A significant clinical impact attributable to CMR exam results was observed in 256 of 361 pts (71%). The CMR exam resulted in a new diagnosis in 69 of 361 (27%) pts. Cardiovascular magnetic resonance imaging results avoided invasive procedures in 38 (11%) pts and prevented additional diagnostic testing in 26 (7%) pts. Comparison of health care savings using CMR as opposed to current standards of care showed a net cost savings of $833 037, ie, per patient cost savings of $2308. Cardiovascular magnetic resonance imaging provides diagnostic image quality in >98% of cases. Cardiovascular magnetic resonance imaging findings have documentable clinical impact on patient management in 71% of pts undergoing the exam, in a cost beneficial manner.

  3. Does non-echo-planar diffusion-weighted magnetic resonance imaging have a role in assisting the clinical diagnosis of cholesteatoma in selected cases?

    Science.gov (United States)

    Nash, R; Lingam, R K; Chandrasekharan, D; Singh, A

    2018-03-01

    To determine the diagnostic performance of diffusion-weighted magnetic resonance imaging in the assessment of patients with suspected, but not clinically evident, cholesteatoma. A retrospective analysis of a prospectively collected database of non-echo-planar diffusion-weighted magnetic resonance imaging studies (using a half-Fourier single-shot turbo-spin echo sequence) was conducted. Clinical records were retrospectively reviewed to determine indications for imaging and operative findings. Seventy-eight investigations in 74 patients with suspected cholesteatoma aged 5.7-79.2 years (mean, 41.7 years) were identified. Operative confirmation was available in 44 ears. Diagnostic accuracy of the imaging technique was calculated using operative findings as a 'gold standard'. Sensitivity of the investigation was examined via comparison with clinically evident cholesteatoma. The accuracy of diffusion-weighted magnetic resonance imaging in assessment of suspected cholesteatoma was 63.6 per cent. The imaging technique was significantly less accurate in assessment of suspected cholesteatoma than clinically evident disease (p < 0.001). Computed tomography and diffusion-weighted magnetic resonance imaging may be complementary in assessment of suspected cholesteatoma, but should be used with caution, and clinical judgement is paramount.

  4. Parallel magnetic resonance imaging

    International Nuclear Information System (INIS)

    Larkman, David J; Nunes, Rita G

    2007-01-01

    Parallel imaging has been the single biggest innovation in magnetic resonance imaging in the last decade. The use of multiple receiver coils to augment the time consuming Fourier encoding has reduced acquisition times significantly. This increase in speed comes at a time when other approaches to acquisition time reduction were reaching engineering and human limits. A brief summary of spatial encoding in MRI is followed by an introduction to the problem parallel imaging is designed to solve. There are a large number of parallel reconstruction algorithms; this article reviews a cross-section, SENSE, SMASH, g-SMASH and GRAPPA, selected to demonstrate the different approaches. Theoretical (the g-factor) and practical (coil design) limits to acquisition speed are reviewed. The practical implementation of parallel imaging is also discussed, in particular coil calibration. How to recognize potential failure modes and their associated artefacts are shown. Well-established applications including angiography, cardiac imaging and applications using echo planar imaging are reviewed and we discuss what makes a good application for parallel imaging. Finally, active research areas where parallel imaging is being used to improve data quality by repairing artefacted images are also reviewed. (invited topical review)

  5. Noncontrast Magnetic Resonance Lymphography.

    Science.gov (United States)

    Arrivé, Lionel; Derhy, Sarah; El Mouhadi, Sanaâ; Monnier-Cholley, Laurence; Menu, Yves; Becker, Corinne

    2016-01-01

    Different imaging techniques have been used for the investigation of the lymphatic channels and lymph glands. Noncontrast magnetic resonance (MR) lymphography has significant advantages in comparison with other imaging modalities. Noncontrast MR lymphography uses very heavily T2-weighted fast spin echo sequences which obtain a nearly complete signal loss in tissue background and specific display of lymphatic vessels with a long T2 relaxation time. The raw data can be processed with different algorithms such as maximum intensity projection algorithm to obtain an anatomic representation. Standard T2-weighted MR images easily demonstrate the location of edema. It appears as subcutaneous infiltration of soft tissue with a classical honeycomb pattern. True collection around the muscular area may be demonstrated in case of severe lymphedema. Lymph nodes may be normal in size, number, and signal intensity; in other cases, lymph nodes may be smaller in size or number of lymph nodes may be restricted. MR lymphography allows a classification of lymphedema in aplasia (no collecting vessels demonstrated); hypoplasia (a small number of lymphatic vessels), and numerical hyperplasia or hyperplasia (with an increased number of lymphatic vessels of greater and abnormal diameter). Noncontrast MR lymphography is a unique noninvasive imaging modality for the diagnosis of lymphedema. It can be used for positive diagnosis, differential diagnosis, and specific evaluation of lymphedema severity. It may also be used for follow-up evaluation after treatment. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  6. Magnetic resonance imaging in neuroradiology

    International Nuclear Information System (INIS)

    Voigt, K.; Lotx, J.W.

    1990-01-01

    Magnetic resonance imaging (MRI) is now accepted as an effective method of investigating a wide range of disorders, especially of the brain and spine. A short introduction on image contrast in MRI is given and the advantages and disadvantages for the different diseases of the brain is discussed. Excellent soft-tissue contrast, multiplanar imaging capabilities and lack of ionising radiation are conspicuous advantages, and it is now established as the investigation of choice in a large number of clinical conditions, especially when the central nervous system is involved. However, it remains only one of a series of imaging modalities. A confident provisional clinical diagnosis is essential for establishing an imaging protocol and the intention should always be to reach a definitive diagnosis in the least invasive and most cost-effective way. 7 figs., 19 refs

  7. Advances in magnetic resonance 9

    CERN Document Server

    Waugh, John S

    2013-01-01

    Advances in Magnetic Resonance, Volume 9 describes the magnetic resonance in split constants and dipolar relaxation. This book discusses the temperature-dependent splitting constants in the ESR spectra of organic free radicals; temperature-dependent splittings in ion pairs; and magnetic resonance induced by electrons. The electron impact excitation of atoms and molecules; intramolecular dipolar relaxation in multi-spin systems; and dipolar cross-correlation problem are also elaborated. This text likewise covers the NMR studies of molecules oriented in thermotropic liquid crystals and diffusion

  8. Advances in magnetic resonance 1

    CERN Document Server

    Waugh, John S

    2013-01-01

    Advances in Magnetic Resonance, Volume 1, discusses developments in various areas of magnetic resonance. The subject matter ranges from original theoretical contributions through syntheses of points of view toward series of phenomena to critical and painstaking tabulations of experimental data. The book contains six chapters and begins with a discussion of the theory of relaxation processes. This is followed by separate chapters on the development of magnetic resonance techniques for studying rate processes in chemistry and the application of these techniques to various problems; the geometri

  9. Central pontine myelinolysis in a chronic alcoholic: A clinical and brain magnetic resonance imaging follow-up

    Directory of Open Access Journals (Sweden)

    Dujmović Irena

    2013-01-01

    Full Text Available Introduction. Central pontine myelinolysis (CPM is a noninflammatory, demyelinating lesion usually localised in the basis pontis. Chronic alcoholism is frequently associated with this condition which may have a variable clinical outcome. Until now, brain magnetic resonance imaging (MRI follow-up in alcoholic CPM cases after alcohol withdrawal has been rarely described. Case report. We reported a 30- year-old male with a 12-year history of alcohol abuse, who presented with inability to stand and walk, nausea, vomiting and somnolence. Neurological examination revealed: impared fixation on lateral gaze, dysarthria, mild spastic quadriparesis, truncal and extremity ataxia, sock-like hypesthesia and moderate decrease in vibration sense in legs. Brain MRI showed a trident-shaped non-enhancing pontine lesion highly suggestive of CPM. After an eight-month alcoholfree follow-up period, the patient’s clinical status significantly improved, while the extent of MRI pontine lesion was merely slightly reduced. Conclusion. The presented case demonstrates that CPM in chronic alcoholics may have a benign clinical course after alcohol withdrawal, which is not necessarily associated with the reduction of lesions on brain MRI. [Projekat Ministarstva nauke Republike Srbije, br. 175031

  10. Reliability of gadolinium-enhanced magnetic resonance imaging findings and their correlation with clinical outcome in patients with sciatica.

    Science.gov (United States)

    el Barzouhi, Abdelilah; Vleggeert-Lankamp, Carmen L A M; Lycklama à Nijeholt, Geert J; Van der Kallen, Bas F; van den Hout, Wilbert B; Koes, Bart W; Peul, Wilco C

    2014-11-01

    Gadolinium-enhanced magnetic resonance imaging (Gd-MRI) is often performed in the evaluation of patients with persistent sciatica after lumbar disc surgery. However, correlation between enhancement and clinical findings is debated, and limited data are available regarding the reliability of enhancement findings. To evaluate the reliability of Gd-MRI findings and their correlation with clinical findings in patients with sciatica. Prospective observational evaluation of patients who were enrolled in a randomized trial with 1-year follow-up. Patients with 6- to 12-week sciatica, who participated in a multicentre randomized clinical trial comparing an early surgery strategy with prolonged conservative care with surgery if needed. In total 204 patients underwent Gd-MRI at baseline and after 1 year. Patients were assessed by means of the Roland Disability Questionnaire (RDQ) for sciatica, visual analog scale (VAS) for leg pain, and patient-reported perceived recovery at 1 year. Kappa coefficients were used to assess interobserver reliability. In total, 204 patients underwent Gd-MRI at baseline and after 1 year. Magnetic resonance imaging findings were correlated to the outcome measures using the Mann-Whitney U test for continuous data and Fisher exact tests for categorical data. Poor-to-moderate agreement was observed regarding Gd enhancement of the herniated disc and compressed nerve root (kappa0.95). Of the 59 patients with an enhancing herniated disc at 1 year, 86% reported recovery compared with 100% of the 12 patients with nonenhancing herniated discs (p=.34). Of the 12 patients with enhancement of the most affected nerve root at 1 year, 83% reported recovery compared with 85% of the 192 patients with no enhancement (p=.69). Patients with and without enhancing herniated discs or nerve roots at 1 year reported comparable outcomes on RDQ and VAS-leg pain. Reliability of Gd-MRI findings was poor-to-moderate and no correlation was observed between enhancement and

  11. Evaluation of carcinoma cervix using magnetic resonance imaging: correlation with clinical FIGO staging and impact on management

    International Nuclear Information System (INIS)

    Dhoot, Nilu Malpani; Bhuyan, Utpal; Kumar, Vinay; Shinagare, Atul; Kataki, Amal Chandra; Barmon, Debabrata

    2012-01-01

    To evaluate carcinoma of the cervix using magnetic resonance imaging (MRI), correlate with clinical approach of International Federation of Gynecology and Obstetrics (FIGO) staging system and to study the impact of MRI findings on patient management. Pathologically confirmed, 75 cases of carcinoma cervix referred to our institute from April 2007 to March 2008 were prospectively studied. Clinical FIGO stage was assigned to each patient by gynaecologists blinded to MRI findings. MRI stage (based on FIGO and TNM) was allotted by radiologists blinded to clinicopathological details. For patients who were operated, histopathological stage was taken as gold standard. For patients who were not operated, gynaecologists decided on a gold standard stage based on all available clinical and imaging data. MR staging was correlated with FIGO staging, with focus on significant alterations in treatment strategy caused due to MRI findings. MRI staging had an accuracy of 89.3% (67/75), while clinical FIGO staging had 61.3% (46/75) accuracy. MRI staging and FIGO staging concurred in 65.6% of the patients and differed in 34.4% of the patients. In about 30.6% (23/75) of the patients, there were relevant additional MRI findings not suspected clinically. The common significant MRI findings were detection of pelvic lymphadenopathy and clinically unsuspected bowel/bladder invasion. The management protocol was significantly altered in 86.9% (20/23) of the patients with additional MRI findings constituting 26.6% (20/75) of the total population. MRI is highly accurate in evaluating carcinoma of the cervix. MRI findings significantly altered therapeutic decisions in 26.6% of the patients. MRI should be considered prior to treatment planning in every patient.

  12. Magnetic resonance angiography in meningovascular syphilis

    Energy Technology Data Exchange (ETDEWEB)

    Gallego, J [Servicio de Neurologia, Hospital de Navarra and Pamplona Univ. Hospital (Spain); Soriano, G [Servicio de Neurologia, Hospital de Navarra and Pamplona Univ. Hospital (Spain); Zubieta, J L [Servicio de Neuroradiologia, Hospital de Navarra and Pamplona Univ. Hospital (Spain); Delgado, G [Servicio de Neurologia, Hospital de Navarra and Pamplona Univ. Hospital (Spain); Villanueva, J A [Servicio de Neurologia, Hospital de Navarra and Pamplona Univ. Hospital (Spain)

    1994-04-01

    Meningovascular neurosyphilis (MN) is an unusual cause of stroke in young adults. The clinical manifestations include prodromal symptoms weeks or months before definitive stroke. The diagnosis is based on clinical findings and examination of the serum and cerebrospinal fluid. We report a case of MN with basilar artery irregularities demonstrated by magnetic resonance angiography. (orig.)

  13. Magnetic resonance angiography in meningovascular syphilis

    International Nuclear Information System (INIS)

    Gallego, J.; Soriano, G.; Zubieta, J.L.; Delgado, G.; Villanueva, J.A.

    1994-01-01

    Meningovascular neurosyphilis (MN) is an unusual cause of stroke in young adults. The clinical manifestations include prodromal symptoms weeks or months before definitive stroke. The diagnosis is based on clinical findings and examination of the serum and cerebrospinal fluid. We report a case of MN with basilar artery irregularities demonstrated by magnetic resonance angiography. (orig.)

  14. Intervertebral disc disease in dogs - Part 2: Comparison of clinical, magnetic resonance imaging, and histological findings in 74 surgically treated dogs

    NARCIS (Netherlands)

    Kranenburg, H.C.; Grinwis, G.C.M.; Bergknut, N.; Gahrmann, Ninke; Voorhout, G.; Hazewinkel, H.A.W.

    The relationship between intervertebral disc (IVD) disease and IVD degeneration remains unclear. The aim of the present study was to compare the clinical severity of IVD herniation (IVDH), determined with a neurological grading system, with findings of magnetic resonance imaging (MRI) and

  15. The Value of Neurosurgical and Intraoperative Magnetic Resonance Imaging and Diffusion Tensor Imaging Tractography in Clinically Integrated Neuroanatomy Modules: A Cross-Sectional Study

    Science.gov (United States)

    Familiari, Giuseppe; Relucenti, Michela; Heyn, Rosemarie; Baldini, Rossella; D'Andrea, Giancarlo; Familiari, Pietro; Bozzao, Alessandro; Raco, Antonino

    2013-01-01

    Neuroanatomy is considered to be one of the most difficult anatomical subjects for students. To provide motivation and improve learning outcomes in this area, clinical cases and neurosurgical images from diffusion tensor imaging (DTI) tractographies produced using an intraoperative magnetic resonance imaging apparatus (MRI/DTI) were presented and…

  16. MAGNETIC-RESONANCE-IMAGING USING A CLINICAL WHOLE-BODY SYSTEM - AN INTRODUCTION TO A USEFUL TECHNIQUE IN SMALL ANIMAL-EXPERIMENTS

    NARCIS (Netherlands)

    WOLF, RFE; LAM, KH; MOOYAART, EL; BLEICHRODT, RP; NIEUWENHUIS, P; SCHAKENRAAD, JM

    A clinical whole body magnetic resonance imaging (MRI) system with high resolution coils was used to obtain non-invasive images of the living rat. The results demonstrate the feasibility of the set-up and the advantages of this new imaging technique: detailed information, no extra costs,

  17. The clinical value of magnetic resonance defecography in males with obstructed defecation syndrome.

    Science.gov (United States)

    Piloni, V; Bergamasco, M; Melara, G; Garavello, P

    2018-03-01

    The aim of the present study was to assess the relationship between symptoms of obstructed defecation and findings on magnetic resonance (MR) defecography in males with obstructed defecation syndrome (ODS). Thirty-six males with ODS who underwent MR defecography at our institution between March 2013 and February 2016 were asked in a telephone interview about their symptoms and subsequent treatment, either medical or surgical. Patients were divided into 2 groups, one with anismus (Group 1) and one with prolapse without anismus (Group 2). The interaction between ODS type and symptoms with MR findings was assessed by multivariate analysis for categorical data using a hierarchical log-linear model. MR imaging findings included lateral and/or posterior rectocele, rectal prolapse, intussusception, ballooning of levator hiatus with impingement of pelvic organs and dyskinetic puborectalis muscle. There were 21 males with ODS due to anismus (Group 1) and 15 with ODS due to rectal prolapse/intussusception (Group 2). Mean age of the entire group was 53.6 ± 4.1 years (range 18-77 years). Patients in Group 1 were slightly older than those in Group 2 (age peak, sixth decade in 47.6 vs 20.0%, p < 0.05). Symptoms most frequently associated with Group 1 patients included small volume and hard feces (85.0%, p < 0.01), excessive strain at stool (81.0%, p < 0.05), tenesmus and fecaloma formation (57.1 and 42.9%, p < 0.05); symptoms most frequently associated with Group 2 patients included mucous discharge, rectal bleeding and pain (86.7%, p < 0.05), prolonged toilet time (73.3%, p < 0.05), fragmented evacuation with or without digitation (66.7%, p < 0.005). Voiding outflow obstruction was more frequent in Group 1 (19.0 vs 13.3%; p < 0.05), while non-bacterial prostatitis and sexual dysfunction prevailed in Group 2 (26.7 and 46.7%, p < 0.05). At MR defecography, two major categories of findings were detected: a dyskinetic pattern (Type 1), seen in all Group 1

  18. Magnetic resonance imaging of chemistry.

    Science.gov (United States)

    Britton, Melanie M

    2010-11-01

    Magnetic resonance imaging (MRI) has long been recognized as one of the most important tools in medical diagnosis and research. However, MRI is also well placed to image chemical reactions and processes, determine the concentration of chemical species, and look at how chemistry couples with environmental factors, such as flow and heterogeneous media. This tutorial review will explain how magnetic resonance imaging works, reviewing its application in chemistry and its ability to directly visualise chemical processes. It will give information on what resolution and contrast are possible, and what chemical and physical parameters can be measured. It will provide examples of the use of MRI to study chemical systems, its application in chemical engineering and the identification of contrast agents for non-clinical applications. A number of studies are presented including investigation of chemical conversion and selectivity in fixed-bed reactors, temperature probes for catalyst pellets, ion mobility during tablet dissolution, solvent dynamics and ion transport in Nafion polymers and the formation of chemical waves and patterns.

  19. Collateral vessels on magnetic resonance angiography in endovascular-treated acute ischemic stroke patients associated with clinical outcomes.

    Science.gov (United States)

    Jiang, Liang; Su, Hao-Bo; Zhang, Ying-Dong; Zhou, Jun-Shan; Geng, Wen; Chen, Huiyou; Xu, Quan; Yin, Xindao; Chen, Yu-Chen

    2017-10-06

    Collateral vessels were considered to be related with outcome in endovascular-treated acute ischemic stroke patients. This study aimed to evaluate whether the collateral vessels on magnetic resonance angiography (MRA) could predict the clinical outcome. Acute stroke patients with internal carotid artery or middle cerebral artery occlusion within 6 hours of symptom onset were included. All patients underwent MRI and received endovascular treatment. The collateral circulations at the Sylvian fissure and the leptomeningeal convexity were evaluated. The preoperative and postoperative infarct volume was measured. The clinical outcome was evaluated by mRS score at 3 months after stroke. Of 55 patients, Cases with insufficient collateral circulation at the Sylvian fissure and leptomeningeal convexity showed that the NIHSS score at arrival and preoperative infarct volume were significantly lower in mRS score of 0-2 (both P collateral status at the leptomeningeal convexity were independent of the clinical outcome at 3 months after stroke (odds ratio (95% confidence interval): 1.094 (1.025-1.168); 9.542 (1.812-50.245) respectively). The change of infarct volume in the group with mRS score of 0-2 was smaller than that with mRS score of 3-6. While multivariate logistic models showed that postoperative infarct volume was non-significant in predicting the clinical outcome after stroke. The extent of collateral circulation at the leptomeningeal convexity may be useful for predicting the functional recovery while the relationship between postoperative infarct volume and clinical outcome still requires for further study.

  20. A study on the clinical significance of magnetic resonance imaging (MRI) findings in patients with cervical spondylotic myelopathy

    International Nuclear Information System (INIS)

    Toyooka, Satoshi

    1997-01-01

    This study was designed to evaluate magnetic resonance (MR) images of the cervical compressive myelopathy. It was also meant to serve as a review of clinical symptoms and an investigation of the usefulness of MRI. Comparative studies were carried out on 110 cases concerning the shape and signal intensity of the spinal cord, anterior epidural venous plexus MR images and clinical symptoms. The shape of the spinal cord and pre- and post-surgical conditions revealed by MRI correlated with clinical symptoms. As for the signal intensity of the spinal cord, in cases in which both high (T2-weighted image) and low (T1-weighted image) signals detected prior to surgery continued after surgery, as well as cases with high and low signals appearing after surgery, had the lower improvement than average. Low signal intensity on T1-weighted images are assumed to indicate irreversible changes of the spinal cord. High signal intensity on T2-weighted images is assumed to indicate both reversible and irreversible changes of the spinal cord. Epidural venous plexus can also be observed in healthy people and is not directly bound to clinical manifestations. Nevertheless, changes in the shape of the epidural venous plexus and signal intensity can reflect venous plexus compression and circulatory changes caused by compression. In the application of MRI to cervical compressive myelopathies, images of changes in the shape and signal intensity of the spinal cord and anterior epidural venous plexus images were considered important observations linked to clinical symptoms. MRI is an essential non-invasive imaging technique for the diagnosis of cervical compressive myelopathy, estimation of prognosis and postoperative follow-up. More investigations of compressive factors, circulatory dynamics of the spinal cord and high quality image are necessary. (author)

  1. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    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. ...

  2. Children's (Pediatric) Magnetic Resonance Imaging

    Medline Plus

    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 Radiologist prepping patient for magnetic resonance ...

  3. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    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 ...

  4. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    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 | ...

  5. Children's (Pediatric) Magnetic Resonance Imaging

    Medline Plus

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

  6. Children's (Pediatric) Magnetic Resonance Imaging

    Medline Plus

    Full Text Available ... or thyroid problems. Any of these conditions may influence the decision on whether contrast material will be ... bear denotes child-specific content. Related Articles and Media Catheter Angiography Magnetic Resonance, Functional (fMRI) - Brain Children's ( ...

  7. Children's (Pediatric) Magnetic Resonance Imaging

    Medline Plus

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

  8. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    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 ...

  9. Children's (Pediatric) Magnetic Resonance Imaging

    Medline Plus

    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 Catheter Angiography Magnetic Resonance, ...

  10. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... be necessary. Your doctor will explain the exact reason why another exam is requested. Sometimes a follow- ... necessary in trauma situations. Although there is no reason to believe that magnetic resonance imaging harms the ...

  11. Magnetic Resonance Imaging. Chapter 15

    Energy Technology Data Exchange (ETDEWEB)

    Leach, M. O. [The Institute of Cancer Research and The Royal Marsden Hospital, London (United Kingdom)

    2014-09-15

    In Chapter 14, the principles of nuclear magnetic resonance were presented, along with an introduction to image forming processes. In this chapter, magnetic resonance imaging (MRI) will be reviewed, beginning with the hardware needed and its impact on image quality. The acquisition processes and image reconstruction will be discussed, as well as the artefacts that are possible, with discussion of the important area of safety and bioeffects completing the chapter.

  12. The nuclear magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Goyer, Ph.

    1997-01-01

    The spectroscopy of nuclear magnetic resonance constitutes a major analytical technique in biological and organic analysis. This technique appears now in the programme of preparatory classes and its teaching is developed in the second year of DEUG. The following article reviews on the nuclear magnetic resonance and on the possibilities it offers to bring to the fore the physico-chemical properties of molecules. (N.C.)

  13. Advances in magnetic resonance 2

    CERN Document Server

    Waugh, John S

    2013-01-01

    Advances in Magnetic Resonance, Volume 2, features a mixture of experimental and theoretical contributions. The book contains four chapters and begins with an ambitious and general treatment of the problem of signal-to-noise ratio in magnetic resonance. This is followed by separate chapters on the interpretation of nuclear relaxation in fluids, with special reference to hydrogen; and various aspects of molecular theory of importance in NMR.

  14. Clinical application of proton magnetic resonance spectroscopy in differential diagnosis of intracranial lesions with ring-like enhancement

    International Nuclear Information System (INIS)

    Lai Ying; Cheng Kailiang; Zhang Mengchao; Liu Yunxia; Wang Wei

    2009-01-01

    Objective: To study the value of clinical application of 1 H proton magnetic resonance spectroscopy ( 1 H MRS) in the differential diagnosis of intracranial lesions with ring-like enhancement. Methods: 28 cases were diagnosed of intracranial lesions with ring-like enhancement by clinical examination and pathologic test. A total of 28 ratios cases included 6 cases high grade glioma, 10 cases of metastatic carcinoma (n=10) and 12 cases of brain abscess, after examined with 1HMRS, the ratios of various metabolites in focal center, enhancement ring,perifocal edema region and normal control group were detected and compared. Results: The ratios of NAA/Cho, Cho/Cr and NAA/Cr in focal center had no significantly differences between high grade glioma and metastatic carcinoma (P>0.05). The peak of NAA was significantly different between high grade glioma and metastatic carcinoma (P 0.05). The peak of AA was characteristic of brain abscess. The ratio of Cho/Cr 0 in brain abscess was significantly lower than those in high grade glioma and metastatic carcinoma (P 0 denoted the Cho content of contralateral normal brain region). These results accorded with the result of pathological examination. Conclusion: 1 HMRS can improve the diagnostic accuracy of intracranial lesions with ring-like enhancement. (authors)

  15. Nuclear magnetic resonance diagnostic apparatus

    International Nuclear Information System (INIS)

    Sugimoto, H.

    1985-01-01

    Nuclear magnetic resonance diagnostic apparatus including a coil for generating a gradient field in a plane perpendicular to a static magnetic field, means for controlling the operation of the coil to rotationally shift in angular steps the gradient direction of the gradient field at an angle pitch of some multiple of the unit index angle through a plurality of rotations to assume all the shift positions of the gradient direction, a rough image reconstructor for reconstructing a rough tomographic image on the basis of nuclear magnetic resonance signals acquired during a rotation of the second gradient magnetic field, a rough image display for depicting the rough tomographic image, a final image reconstructor for reconstructing a final tomographic image on the basis of all nuclear magnetic resonance signals corresponding to all of the expected rotation shift positions acquired during a plurality of rotations and a final image display for depicting the final tomographic image

  16. Nuclear magnetic resonance and earth magnetic field

    International Nuclear Information System (INIS)

    Anon.

    1998-01-01

    Nuclear magnetic resonance concerns nuclei whose spin is different from 0. These nuclei exposed to a magnetic field is comparable to a peg top spinning around its axis while being moved by a precession movement called Larmor precession. This article presents an experiment whose aim is to reveal nuclear magnetism of nuclei by observing Larmor precession phenomena due to the earth magnetic field. The earth magnetic field being too weak, it is necessary to increase the magnetization of the sample during a polarization phase. First the sample is submitted to a magnetic field B perpendicular to the earth magnetic field B 0 , then B is cut off and the nuclei move back to their equilibrium position by executing a precession movement due to B 0 field. (A.C.)

  17. Is magnetic resonance imaging reliable in predicting clinical outcome after articular cartilage repair of the knee?

    NARCIS (Netherlands)

    de Windt, T.S.; Welsch, G.H.; Brittberg, M.; Vonk, L.A.; Marlovits, S.; Trattnig, S.; Saris, Daniël B.F.

    2013-01-01

    Background: While MRI can provide a detailed morphological evaluation after articular cartilage repair, its additional value in determining clinical outcome has yet to be determined. Purpose: To evaluate the correlation between MRI and clinical outcome after cartilage repair and to identify

  18. Reproducibility of small animal cine and scar cardiac magnetic resonance imaging using a clinical 3.0 tesla system

    International Nuclear Information System (INIS)

    Manka, Robert; Jahnke, Cosima; Hucko, Thomas; Dietrich, Thore; Gebker, Rolf; Schnackenburg, Bernhard; Graf, Kristof; Paetsch, Ingo

    2013-01-01

    To evaluate the inter-study, inter-reader and intra-reader reproducibility of cardiac cine and scar imaging in rats using a clinical 3.0 Tesla magnetic resonance (MR) system. Thirty-three adult rats (Sprague–Dawley) were imaged 24 hours after surgical occlusion of the left anterior descending coronary artery using a 3.0 Tesla clinical MR scanner (Philips Healthcare, Best, The Netherlands) equipped with a dedicated 70 mm solenoid receive-only coil. Left-ventricular (LV) volumes, mass, ejection fraction and amount of myocardial scar tissue were measured. Intra-and inter-observer reproducibility was assessed in all animals. In addition, repeat MR exams were performed in 6 randomly chosen rats within 24 hours to assess inter-study reproducibility. The MR imaging protocol was successfully completed in 32 (97%) animals. Bland-Altman analysis demonstrated high intra-reader reproducibility (mean bias%: LV end-diastolic volume (LVEDV), -1.7%; LV end-systolic volume (LVESV), -2.2%; LV ejection fraction (LVEF), 1.0%; LV mass, -2.7%; and scar mass, -1.2%) and high inter-reader reproducibility (mean bias%: LVEDV, 3.3%; LVESV, 6.2%; LVEF, -4.8%; LV mass, -1.9%; and scar mass, -1.8%). In addition, a high inter-study reproducibility was found (mean bias%: LVEDV, 0.1%; LVESV, -1.8%; LVEF, 1.0%; LV mass, -4.6%; and scar mass, -6.2%). Cardiac MR imaging of rats yielded highly reproducible measurements of cardiac volumes/function and myocardial infarct size on a clinical 3.0 Tesla MR scanner system. Consequently, more widely available high field clinical MR scanners can be employed for small animal imaging of the heart e.g. when aiming at serial assessments during therapeutic intervention studies

  19. Magnetic resonance imaging of Parkinsonism

    International Nuclear Information System (INIS)

    Nakamura, Yusaku; Takahashi, Mitsuo; Kitaguchi, Masataka; Akaneya, Yukio; Mitui, Yoshiyuki; Tanaka, Hisashi

    1991-01-01

    We studied eighteen patients affected by Parkinsonism with symptoms of tremor, bradykinesia, or rigidity using magnetic resonance imaging (MRI). Patients ranged in age from 34 to 80 years (mean 62.8±11.6 years), and the duration of their disease had been 3.8±3.2 years. MRI examinations were performed with Shimazu and Siemens superconducting magnets, operating at 0.5 and 1.5 T magnetic fields, respectively. Both T 1 - and T 2 -weighted spin echo (SE) pulse sequences were used. In eight patients (44.4%), MRI demonstrated bilateral multiple lacunar infarction of the basal ganglia. The most common abnormality identified was multiple, bilateral lacunar infarcts in the lateral portion of the putamen. The average size of the lacunar infarction of the putamen was less than half that of the entire putamen. Patients with multiple lacunar infarction were significantly older than the other patients and had lower Yahr's scores. The clinical symptoms of patients with bilateral multiple lacunar infarction of the basal ganglia were compatible with the diagnosis of arteriosclerotic Parkinsonism of akinetic rigid type. It has been suggested that multiple lacunar infarction of the basal ganglia may have led to Parkinsonism in these patients. (author)

  20. Magnetic Resonance Imaging

    Science.gov (United States)

    ... Permanent cosmetics or tattoos Dentures/teeth with magnetic keepers Other implants that involve magnets Medication patch (i. ... or longer. You’ll be told ahead of time just how long your scan is expected to ...

  1. Noble gas magnetic resonator

    Science.gov (United States)

    Walker, Thad Gilbert; Lancor, Brian Robert; Wyllie, Robert

    2014-04-15

    Precise measurements of a precessional rate of noble gas in a magnetic field is obtained by constraining the time averaged direction of the spins of a stimulating alkali gas to lie in a plane transverse to the magnetic field. In this way, the magnetic field of the alkali gas does not provide a net contribution to the precessional rate of the noble gas.

  2. Clinically relevant magnetic resonance imaging (MRI findings in elite swimmers’ shoulders

    Directory of Open Access Journals (Sweden)

    Arno Celliers

    2017-01-01

    Objective: To assess clinically relevant MRI findings in the shoulders of symptomatic and asymptomatic elite swimmers. Method: Twenty (aged 16–23 years elite swimmers completed questionnaires on their swimming training, pain and shoulder function. MRI of both shoulders (n = 40 were performed and all swimmers were given a standardised clinical shoulder examination. Results: Both shoulders of 11 male and 9 female elite swimmers (n = 40 were examined. Eleven of the 40 shoulders were clinically symptomatic and 29 were asymptomatic. The most common clinical finding in both the symptomatic and asymptomatic shoulders was impingement during internal rotation, with impingement in 54.5% of the symptomatic shoulders and in 31.0% of the asymptomatic shoulders. The most common MRI findings in the symptomatic and asymptomatic shoulders were supraspinatus tendinosis (45.5% vs. 20.7%, subacromial subdeltoid fluid (45.5% vs. 34.5%, increased signal in the AC Joint (45.5% vs. 37.9% and AC joint arthrosis (36.4% vs. 34.5%. Thirty-nine (97.5% of the shoulders showed abnormal MRI features. Conclusion: MRI findings in the symptomatic and asymptomatic shoulders of young elite swimmers are similar and care should be taken when reporting shoulder MRIs in these athletes. Asymptomatic shoulders demonstrate manifold MRI abnormalities that may be radiologically significant but appear not to be clinically significant.

  3. Magnetic resonance imaging and clinical features of glenoid labral flap tears

    Energy Technology Data Exchange (ETDEWEB)

    Stewart, Jessica K.; Vinson, Emily N. [Duke University Hospital, Department of Radiology, Durham, NC (United States); Taylor, Dean C. [Duke University Hospital, Department of Orthopaedic Surgery, Durham, NC (United States)

    2017-08-15

    Displaced flaps of glenoid labral tissue are an uncommonly encountered finding on MRI of the shoulder, and are of unclear clinical significance. The purpose of this study is to describe the imaging characteristics of displaced glenoid labral flaps, evaluate for any common concomitant injuries, and identify the typical clinical presentation and management of patients with this lesion. This retrospective, observational study was approved by the institutional review board. Nineteen patients with flap-type tears of the labrum on preoperative MRI were identified. Each examination was retrospectively reviewed by two radiologists for size, location, and signal intensity of the displaced flap of tissue, in addition to any co-existing labrum or cartilage pathological conditions and clinical information. All displaced flaps extended from the inferior margin of the glenoid into the axillary recess. The average size of the visualized flap was 10.9 by 6.0 by 2.6 mm. Seventy percent of the flaps had signal intensity isointense to labrum and hypointense to hyaline cartilage on T2-weighted images. All 19 patients had concomitant labral pathological conditions and 63% had cartilage defects, visualized on MRI. Clinical evidence of shoulder instability was seen in 83% of patients, and 67% were managed surgically. Glenoid labral flap tears have distinct imaging characteristics that may aid in their identification. Their presence should prompt careful evaluation of the glenoid articular cartilage. Recognition of a labral flap tear may have clinical importance, as 83% of patients with this finding demonstrated clinical evidence of shoulder instability, often requiring surgical intervention. (orig.)

  4. Magnetic resonance imaging and clinical features of glenoid labral flap tears

    International Nuclear Information System (INIS)

    Stewart, Jessica K.; Vinson, Emily N.; Taylor, Dean C.

    2017-01-01

    Displaced flaps of glenoid labral tissue are an uncommonly encountered finding on MRI of the shoulder, and are of unclear clinical significance. The purpose of this study is to describe the imaging characteristics of displaced glenoid labral flaps, evaluate for any common concomitant injuries, and identify the typical clinical presentation and management of patients with this lesion. This retrospective, observational study was approved by the institutional review board. Nineteen patients with flap-type tears of the labrum on preoperative MRI were identified. Each examination was retrospectively reviewed by two radiologists for size, location, and signal intensity of the displaced flap of tissue, in addition to any co-existing labrum or cartilage pathological conditions and clinical information. All displaced flaps extended from the inferior margin of the glenoid into the axillary recess. The average size of the visualized flap was 10.9 by 6.0 by 2.6 mm. Seventy percent of the flaps had signal intensity isointense to labrum and hypointense to hyaline cartilage on T2-weighted images. All 19 patients had concomitant labral pathological conditions and 63% had cartilage defects, visualized on MRI. Clinical evidence of shoulder instability was seen in 83% of patients, and 67% were managed surgically. Glenoid labral flap tears have distinct imaging characteristics that may aid in their identification. Their presence should prompt careful evaluation of the glenoid articular cartilage. Recognition of a labral flap tear may have clinical importance, as 83% of patients with this finding demonstrated clinical evidence of shoulder instability, often requiring surgical intervention. (orig.)

  5. Characterization of the onboard imaging unit for the first clinical magnetic resonance image guided radiation therapy system

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Yanle, E-mail: Hu.Yanle@mayo.edu [Department of Radiation Oncology, Washington University School of Medicine, St. Louis, Missouri 63110 and Department of Radiation Oncology, Mayo Clinic in Arizona, Phoenix, Arizona 85054 (United States); Rankine, Leith; Green, Olga L.; Kashani, Rojano; Li, H. Harold; Li, Hua; Rodriguez, Vivian; Santanam, Lakshmi; Wooten, H. Omar; Mutic, Sasa [Department of Radiation Oncology, Washington University School of Medicine, St. Louis, Missouri 63110 (United States); Nana, Roger; Shvartsman, Shmaryu; Victoria, James; Dempsey, James F. [ViewRay, Inc., Oakwood Village, Ohio 44146 (United States)

    2015-10-15

    Purpose: To characterize the performance of the onboard imaging unit for the first clinical magnetic resonance image guided radiation therapy (MR-IGRT) system. Methods: The imaging performance characterization included four components: ACR (the American College of Radiology) phantom test, spatial integrity, coil signal to noise ratio (SNR) and uniformity, and magnetic field homogeneity. The ACR phantom test was performed in accordance with the ACR phantom test guidance. The spatial integrity test was evaluated using a 40.8 × 40.8 × 40.8 cm{sup 3} spatial integrity phantom. MR and computed tomography (CT) images of the phantom were acquired and coregistered. Objects were identified around the surfaces of 20 and 35 cm diameters of spherical volume (DSVs) on both the MR and CT images. Geometric distortion was quantified using deviation in object location between the MR and CT images. The coil SNR test was performed according to the national electrical manufacturers association (NEMA) standards MS-1 and MS-9. The magnetic field homogeneity test was measured using field camera and spectral peak methods. Results: For the ACR tests, the slice position error was less than 0.10 cm, the slice thickness error was less than 0.05 cm, the resolved high-contrast spatial resolution was 0.09 cm, the resolved low-contrast spokes were more than 25, the image intensity uniformity was above 93%, and the percentage ghosting was less than 0.22%. All were within the ACR recommended specifications. The maximum geometric distortions within the 20 and 35 cm DSVs were 0.10 and 0.18 cm for high spatial resolution three-dimensional images and 0.08 and 0.20 cm for high temporal resolution two dimensional cine images based on the distance-to-phantom-center method. The average SNR was 12.0 for the body coil, 42.9 for the combined torso coil, and 44.0 for the combined head and neck coil. Magnetic field homogeneities at gantry angles of 0°, 30°, 60°, 90°, and 120° were 23.55, 20.43, 18.76, 19

  6. Characterization of the onboard imaging unit for the first clinical magnetic resonance image guided radiation therapy system

    International Nuclear Information System (INIS)

    Hu, Yanle; Rankine, Leith; Green, Olga L.; Kashani, Rojano; Li, H. Harold; Li, Hua; Rodriguez, Vivian; Santanam, Lakshmi; Wooten, H. Omar; Mutic, Sasa; Nana, Roger; Shvartsman, Shmaryu; Victoria, James; Dempsey, James F.

    2015-01-01

    Purpose: To characterize the performance of the onboard imaging unit for the first clinical magnetic resonance image guided radiation therapy (MR-IGRT) system. Methods: The imaging performance characterization included four components: ACR (the American College of Radiology) phantom test, spatial integrity, coil signal to noise ratio (SNR) and uniformity, and magnetic field homogeneity. The ACR phantom test was performed in accordance with the ACR phantom test guidance. The spatial integrity test was evaluated using a 40.8 × 40.8 × 40.8 cm 3 spatial integrity phantom. MR and computed tomography (CT) images of the phantom were acquired and coregistered. Objects were identified around the surfaces of 20 and 35 cm diameters of spherical volume (DSVs) on both the MR and CT images. Geometric distortion was quantified using deviation in object location between the MR and CT images. The coil SNR test was performed according to the national electrical manufacturers association (NEMA) standards MS-1 and MS-9. The magnetic field homogeneity test was measured using field camera and spectral peak methods. Results: For the ACR tests, the slice position error was less than 0.10 cm, the slice thickness error was less than 0.05 cm, the resolved high-contrast spatial resolution was 0.09 cm, the resolved low-contrast spokes were more than 25, the image intensity uniformity was above 93%, and the percentage ghosting was less than 0.22%. All were within the ACR recommended specifications. The maximum geometric distortions within the 20 and 35 cm DSVs were 0.10 and 0.18 cm for high spatial resolution three-dimensional images and 0.08 and 0.20 cm for high temporal resolution two dimensional cine images based on the distance-to-phantom-center method. The average SNR was 12.0 for the body coil, 42.9 for the combined torso coil, and 44.0 for the combined head and neck coil. Magnetic field homogeneities at gantry angles of 0°, 30°, 60°, 90°, and 120° were 23.55, 20.43, 18.76, 19

  7. Functional magnetic resonance imaging study of external source memory and its relation to cognitive insight in non-clinical subjects.

    Science.gov (United States)

    Buchy, Lisa; Hawco, Colin; Bodnar, Michael; Izadi, Sarah; Dell'Elce, Jennifer; Messina, Katrina; Lepage, Martin

    2014-09-01

    Previous research has linked cognitive insight (a measure of self-reflectiveness and self-certainty) in psychosis with neurocognitive and neuroanatomical disturbances in the fronto-hippocampal neural network. The authors' goal was to use functional magnetic resonance imaging (fMRI) to investigate the neural correlates of cognitive insight during an external source memory paradigm in non-clinical subjects. At encoding, 24 non-clinical subjects travelled through a virtual city where they came across 20 separate people, each paired with a unique object in a distinct location. fMRI data were then acquired while participants viewed images of the city, and completed source recognition memory judgments of where and with whom objects were seen, which is known to involve prefrontal cortex. Cognitive insight was assessed with the Beck Cognitive Insight Scale. External source memory was associated with neural activity in a widespread network consisting of frontal cortex, including ventrolateral prefrontal cortex (VLPFC), temporal and occipital cortices. Activation in VLPFC correlated with higher self-reflectiveness and activation in midbrain correlated with lower self-certainty during source memory attributions. Neither self-reflectiveness nor self-certainty significantly correlated with source memory accuracy. By means of virtual reality and in the context of an external source memory paradigm, the study identified a preliminary functional neural basis for cognitive insight in the VLPFC in healthy people that accords with our fronto-hippocampal theoretical model as well as recent neuroimaging data in people with psychosis. The results may facilitate the understanding of the role of neural mechanisms in psychotic disorders associated with cognitive insight distortions. © 2014 The Authors. Psychiatry and Clinical Neurosciences © 2014 Japanese Society of Psychiatry and Neurology.

  8. SU-E-J-157: Improving the Quality of T2-Weighted 4D Magnetic Resonance Imaging for Clinical Evaluation

    International Nuclear Information System (INIS)

    Du, D; Mutic, S; Hu, Y; Caruthers, S; Glide-Hurst, C; Low, D

    2014-01-01

    Purpose: To develop an imaging technique that enables us to acquire T2- weighted 4D Magnetic Resonance Imaging (4DMRI) with sufficient spatial coverage, temporal resolution and spatial resolution for clinical evaluation. Methods: T2-weighed 4DMRI images were acquired from a healthy volunteer using a respiratory amplitude triggered T2-weighted Turbo Spin Echo sequence. 10 respiratory states were used to equally sample the respiratory range based on amplitude (0%, 20%i, 40%i, 60%i, 80%i, 100%, 80%e, 60%e, 40%e and 20%e). To avoid frequent scanning halts, a methodology was devised that split 10 respiratory states into two packages in an interleaved manner and packages were acquired separately. Sixty 3mm sagittal slices at 1.5mm in-plane spatial resolution were acquired to offer good spatial coverage and reasonable spatial resolution. The in-plane field of view was 375mm × 260mm with nominal scan time of 3 minutes 42 seconds. Acquired 2D images at the same respiratory state were combined to form the 3D image set corresponding to that respiratory state and reconstructed in the coronal view to evaluate whether all slices were at the same respiratory state. 3D image sets of 10 respiratory states represented a complete 4D MRI image set. Results: T2-weighted 4DMRI image were acquired in 10 minutes which was within clinical acceptable range. Qualitatively, the acquired MRI images had good image quality for delineation purposes. There were no abrupt position changes in reconstructed coronal images which confirmed that all sagittal slices were in the same respiratory state. Conclusion: We demonstrated it was feasible to acquire T2-weighted 4DMRI image set within a practical amount of time (10 minutes) that had good temporal resolution (10 respiratory states), spatial resolution (1.5mm × 1.5mm × 3.0mm) and spatial coverage (60 slices) for future clinical evaluation

  9. Perfusion magnetic resonance imaging with continuous arterial spin labeling: methods and clinical applications in the central nervous system

    Energy Technology Data Exchange (ETDEWEB)

    Detre, John A. E-mail: detre@mail.med.upenn.edu; Alsop, David C

    1999-05-01

    Several methods are now available for measuring cerebral perfusion and related hemodynamic parameters using magnetic resonance imaging (MRI). One class of techniques utilizes electromagnetically labeled arterial blood water as a noninvasive diffusible tracer for blood flow measurements. The electromagnetically labeled tracer has a decay rate of T1, which is sufficiently long to allow perfusion of the tissue and microvasculature to be detected. Alternatively, electromagnetic arterial spin labeling (ASL) may be used to obtain qualitative perfusion contrast for detecting changes in blood flow, similar to the use of susceptibility contrast in blood oxygenation level dependent functional MRI (BOLD fMRI) to detect functional activation in the brain. The ability to obtain blood flow maps using a non-invasive and widely available modality such as MRI should greatly enhance the utility of blood flow measurement as a means of gaining further insight into the broad range of hemodynamically related physiology and pathophysiology. This article describes the biophysical considerations pertaining to the generation of quantitative blood flow maps using a particular form of ASL in which arterial blood water is continuously labeled, termed continuous arterial spin labeling (CASL). Technical advances permit multislice perfusion imaging using CASL with reduced sensitivity to motion and transit time effects. Interpretable cerebral perfusion images can now be reliably obtained in a variety of clinical settings including acute stroke, chronic cerebrovascular disease, degenerative diseases and epilepsy. Over the past several years, the technical and theoretical foundations of CASL perfusion MRI techniques have evolved from feasibility studies into practical usage. Currently existing methodologies are sufficient to make reliable and clinically relevant observations which complement structural assessment using MRI. Future technical improvements should further reduce the acquisition times

  10. Clinical and magnetic resonance observations in cerebral small-vessel disease

    NARCIS (Netherlands)

    Kwa, V.I.H.

    1999-01-01

    The study reported in this thesis tried to address the following questions: 1. Is it possible to detect genetic factors and vascular risk factors that are specifically associated with the development of small- or large-vessel disease? 2. Are the different clinical and MRI manifestations, that are

  11. Magnetic resonance imaging of sacroiliitis in early seronegative spondylarthropathy. Abnormalities correlated to clinical and laboratory findings

    DEFF Research Database (Denmark)

    Puhakka, K B; Jurik, A G; Schiøttz-Christensen, Berit

    2004-01-01

    OBJECTIVE: To compare a new MRI scoring system of the sacroiliac joints (SIJs) in early spondylarthropathy (SpA) with clinical and laboratory parameters. METHODS: Forty-one patients (24 males, 17 females) with a median age of 26 yr and a median duration of inflammatory low back pain of 19 months...

  12. Role of magnetic resonance imaging in the clinical management of the acutely locked knee

    International Nuclear Information System (INIS)

    McNally, Eugene G.; Nasser, Khalid N.; Dawson, Stewart; Goh, Leslie A.

    2002-01-01

    To explore prospectively the hypothesis that MRI of the acutely locked knee can alter surgical decision-making.Design and patients. The study group comprised patients with a clinical diagnosis of knee locking requiring arthroscopy. The decision to carry out arthroscopy was made by an experienced consultant orthopaedic surgeon specialising in trauma and recorded in the patient's notes prior to MRI. Preoperative MRI was carried out using a 1.5 T system. The management was altered from surgical to conservative treatment in 20 (48%) patients on the basis of the MR findings. Arthroscopy was limited to patients with an MR diagnosis of a mechanical block, usually a displaced meniscal tear or loose body. Both patient groups were followed clinically until symptoms resolved.Results. Forty-two patients were entered into the study. MRI identified a mechanical cause for locking in 22 patients (21 avulsion meniscal tears and 1 loose body). All were confirmed at arthroscopy. Twenty patients were changed from operative to non-operative treatment on the basis of the MRI findings. One patient in this group required a delayed arthroscopy for an impinging anterior cruciate ligament stump. The sensitivity/specificity/accuracy of MRI in identifying patients who require arthroscopy was therefore 96%/100%/98% respectively.Conclusion. MRI can successfully segregate patients with a clinical diagnosis of mechanical locking into those who have a true mechanical block and those who can be treated conservatively. MRI should precede arthroscopy in this clinical setting. (orig.)

  13. Usefulness of 3-Tesla cardiac magnetic resonance imaging in the assessment of aortic stenosis severity in routine clinical practice.

    Science.gov (United States)

    Levy, Franck; Iacuzio, Laura; Civaia, Filippo; Rusek, Stephane; Dommerc, Carine; Hugues, Nicolas; Alexandrescu, Clara; Dor, Vincent; Tribouilloy, Christophe; Dreyfus, Gilles

    2016-11-01

    Recently, 1.5-Tesla cardiac magnetic resonance imaging (CMR) was reported to provide a reliable alternative to transthoracic echocardiography (TTE) for the quantification of aortic stenosis (AS) severity. Few data are available using higher magnetic field strength MRI systems in this context. To evaluate the feasibility and reproducibility of the assessment of aortic valve area (AVA) using 3-Tesla CMR in routine clinical practice, and to assess concordance between TTE and CMR for the estimation of AS severity. Ninety-one consecutive patients (60 men; mean age 74±10years) with known AS documented by TTE were included prospectively in the study. All patients underwent comprehensive TTE and CMR examination, including AVA estimation using the TTE continuity equation (0.81±0.18cm 2 ), direct CMR planimetry (CMRp) (0.90±0.22cm 2 ) and CMR using Hakki's formula (CMRhk), a simplified Gorlin formula (0.70±0.19cm 2 ). Although significant agreement with TTE was found for CMRp (r=0.72) and CMRhk (r=0.66), CMRp slightly overestimated (bias=0.11±0.18cm 2 ) and CMRhk slightly underestimated (bias=-0.11±0.17cm 2 ) AVA compared with TTE. Inter- and intraobserver reproducibilities of CMR measurements were excellent (r=0.72 and r=0.74 for CMRp and r=0.88 and r=0.92 for peak aortic velocity, respectively). 3-Tesla CMR is a feasible, radiation-free, reproducible imaging modality for the estimation of severity of AS in routine practice, knowing that CMRp tends to overestimate AVA and CMRhk to underestimate AVA compared with TTE. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  14. Relationship between magnetic resonance imaging and clinical results of decompression surgery for cervical myelopathy

    International Nuclear Information System (INIS)

    Okumura, Hiroshi

    1993-01-01

    MR imaging was investigated before and after surgery in 60 cases of cervical myelopathy. A preoperative high-signal-intensity area in the spinal cord was thought to be an important indicator of poor prognosis, because the recovery ratio of the preoperative high-signal group was 32±24%, while that of the normal-signal group was 86±15%. But, a high-signal-intensity area had no significant correlation with the morbidity period, preoperative clinical severity and degree of cord compression. There was a significant correlation between postoperative MR imaging and the neurological prognosis. And, atrophy and high-signal-intensity area in the spinal cord were frequently seen in cases of poor neurological postoperative recovery, corresponding to the morbidity period, preoperative clinical severity and degree of cord compression. MR imaging can serve as a useful tool to assess cervical myelopathy and to forecast the postoperative prognosis. (author)

  15. Temporomandibular disorders – validity of clinical diagnostics compared to magnetic resonance imaging

    OpenAIRE

    BADEL, TOMISLAV; MAROTTI, MILJENKO; SAVIĆ PAVIČIN, IVANA; DULČIĆ, NIKŠA; ZADRAVEC, DIJANA; KERN, JOSIPA

    2011-01-01

    Background and Purpose: Orthopedic examination techniques of the musculoskeletal system contribute to the successful diagnostics of temporomandibular disorders (TMD). The purpose of this study is to determine the validity of TMD clinical diagnostics by comparing the findings of manual functional analysis (MFA) and the results of MRI of temporomandibular joint (TMJ). The diagnostic significance of limited mouth opening and pain upon passive mouth opening were taken into consideration. M...

  16. Septo-optic dysplasia plus: clinical presentation and magnetic resonance imaging findings

    International Nuclear Information System (INIS)

    Matushita Junior, Joao Paulo K.; Tiel, Chan; Py, Marco; Batista, Raquel Ribeiro; Gasparetto, Emerson L.

    2010-01-01

    Septo-optic dysplasia (SOD) is a heterogeneous developmental malformation characterized by optic nerve hypoplasia associated with dysgenesis of the septum pellucidum and other cerebral malformations. The clinical manifestations include psychomotor retardation, visual impairment, thermoregulatory disturbances, conjugated hyperbilirubinemia and seizures. In 2000, Miller et al. first named the association of SOD and cortical dysplasia as SOD-plus. In this report, all the cases had severe clinical impairment, presenting global developmental delay and spastic motor deficits. Subsequent reports of SOD-plus also stressed the psychomotor development delay, spastic motor deficits and seizures seen in these patients, emphasizing the severity of the brain involvement. Recently, Kwak et al. reported a case of SOD-plus presenting with cortical dysplasia involving the insular cortex bilaterally. However, differently from all the previous reports, the patient had no signs or symptoms of cortical dysfunction, except for one episode of seizure. We report an additional case of SOD-plus, which presented extensive cortical malformation, with no signs or symptoms of cortical dysfunction. We suggest that similar to the classical form of SOD, the clinical presentation in patients with SOD-plus can also range from mild to extremely severe. (author)

  17. Septo-optic dysplasia plus: clinical presentation and magnetic resonance imaging findings

    Energy Technology Data Exchange (ETDEWEB)

    Matushita Junior, Joao Paulo K. [Instituto de Pos-Graduacao Medica Carlos Chagas (IPGMCC), Rio de Janeiro, RJ (Brazil); Tiel, Chan; Py, Marco [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Inst. de Neurologia Deolindo Couto; Batista, Raquel Ribeiro [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Hospital Universitario Clementino Fraga Filho; Gasparetto, Emerson L., E-mail: egasparetto@gmail.co [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Dept. de Radiologia

    2010-04-15

    Septo-optic dysplasia (SOD) is a heterogeneous developmental malformation characterized by optic nerve hypoplasia associated with dysgenesis of the septum pellucidum and other cerebral malformations. The clinical manifestations include psychomotor retardation, visual impairment, thermoregulatory disturbances, conjugated hyperbilirubinemia and seizures. In 2000, Miller et al. first named the association of SOD and cortical dysplasia as SOD-plus. In this report, all the cases had severe clinical impairment, presenting global developmental delay and spastic motor deficits. Subsequent reports of SOD-plus also stressed the psychomotor development delay, spastic motor deficits and seizures seen in these patients, emphasizing the severity of the brain involvement. Recently, Kwak et al. reported a case of SOD-plus presenting with cortical dysplasia involving the insular cortex bilaterally. However, differently from all the previous reports, the patient had no signs or symptoms of cortical dysfunction, except for one episode of seizure. We report an additional case of SOD-plus, which presented extensive cortical malformation, with no signs or symptoms of cortical dysfunction. We suggest that similar to the classical form of SOD, the clinical presentation in patients with SOD-plus can also range from mild to extremely severe. (author)

  18. Implementation of nuclear magnetic resonance polymer-gel dosimetry into clinical practice

    International Nuclear Information System (INIS)

    Novotny, Josef Jr.

    2003-01-01

    The aim of this thesis research was to evaluate some basic properties of the polymer-gel dosimeter and test it in clinical practice. Dependence of polymer-gel dosimeter sensitivity on different photon and electron energies as well as on different mean dose rates of standard clinically used linear accelerator was studied. A physical/mathematical description of the effect of temperature on the polymer-gel dosimeter, able to correct a dosimeter 1/T2 response for different temperatures during the NMR measurement, was developed. The polymer-gel dosimeter was tested for the verification of stereotactic radiosurgery techniques with the Leksell Gamma Knife. There was an observed trend in polymer-gel dosimeter sensitivity dependence on quality index for the high-energy x ray beams. Similarly, there was an observed trend in dosimeter sensitivity dependence on mean electron energy. It was demonstrated that these trends were statistically significant. Polymer-gel dosimeter sensitivity was decreased with increased photon or electron energy. There was observed no trend in polymer-gel dosimeter sensitivity dependence on mean dose rates for both photon and electron beams within experimental errors. It was demonstrated in this study that the NMR 1/T2-dose response is increased for lower temperatures of the evaluated polymer-gel samples. The relaxation rate response can be expressed as a function consisting of two terms, one denoted for the temperature dependence and the other one for the dose dependence. Two clinical applications of the polymer-gel dosimeter were demonstrated in this study. The first experiment allowed a check of the entire stereotactic procedure with the Leksell gamma knife including target stereotactic localization on NMR, treatment planning, and irradiation. The second experiment evaluated dosimetric and geometric inaccuracies associated with the stereotactic irradiation of the experimental rat brain. It was demonstrated that polymer-gel can be effectively used

  19. Basic principles of magnetic resonance imaging in cerebral ischemia and initial clinical experience

    International Nuclear Information System (INIS)

    Brant-Zawadzki, M.; Solomon, M.; Newton, T.H.; Weinstein, P.; Schmidley, J.; Norman, D.

    1985-01-01

    NMR tomography proved to be a method superior to computerized tomography (CT) in terms of sensitivity in the diagnosis of pathological changes in the brain. The article on hand gives a brief survey on the principle of the method and demonstrates the superiority of NMR tomography to CT exemplified by images taken from a number of cases. Instrumental factors influencing diagnosis of cerebral ischaemie are discussed. Clinical studies performed on more than 20 partients with suspected infarct revealed the superiority of NMR tomography to CT. (MG) [de

  20. Fourier transform nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Geick, R.

    1981-01-01

    This review starts with the basic principles of resonance phenomena in physical systems. Especially, the connection is shown between the properties of these systems and Fourier transforms. Next, we discuss the principles of nuclear magnetic resonance. Starting from the general properties of physical systems showing resonance phenomena and from the special properties of nuclear spin systems, the main part of this paper reviews pulse and Fourier methods in nuclear magnetic resonance. Among pulse methods, an introduction will be given to spin echoes, and, apart from the principle of Fourier transform nuclear magnetic resonance, an introduction to the technical problems of this method, e.g. resolution in the frequency domain, aliasing, phase and intensity errors, stationary state of the spin systems for repetitive measurements, proton decoupling, and application of Fourier methods to systems in a nonequilibrium state. The last section is devoted to special applications of Fourier methods and recent developments, e.g. measurement of relaxation times, solvent peak suppression, 'rapid scan'-method, methods for suppressing the effects of dipolar coupling in solids, two-dimensional Fourier transform nuclear magnetic resonance, and spin mapping or zeugmatography. (author)

  1. Magnetic resonance and porous materials

    International Nuclear Information System (INIS)

    McDonald, P.; Strange, J.

    1998-01-01

    Mention the words magnetic resonance to your medical advisor and he or she will immediately think of a multi-million pound scanner that peers deep into the brain. A chemist, on the other hand, will imagine a machine that costs several hundred thousand pounds and produces high-resolution spectra for chemical analysis. Food technologists will probably think of a bench-top instrument for determining moisture content, while an oil prospector will envisage a device that can be operated several kilometres down an oil well. To a physicist the term is more likely to conjure up a mental picture of nuclear spins precessing in a magnetic field. These examples illustrate the diverse aspects of a phenomenon discovered by physicists over 50 years ago. Electron spin resonance was first discovered by Russian scientists, and nuclear magnetic resonance was discovered in the US shortly afterwards by Ed Purcell at Harvard University and Felix Bloch at Stanford University. Today, nuclear magnetic resonance (NMR) is the most widely used technique. Modern NMR machines are making it possible to probe microstructure and molecular movement in materials as diverse as polymers, cements, rocks, soil and foods. NMR allows the distribution of different components in a material to be determined with a resolution approaching 1μm, although the signal can be sensitive to even smaller lengthscales. In this article the authors describe how physicists are still developing magnetic resonance to exploit a range of new applications. (UK)

  2. The clinical value of routine whole-body magnetic resonance imaging (MRI) in palliative care

    Energy Technology Data Exchange (ETDEWEB)

    Geitung, Jonn Terje (Department of Radiology, Haraldspass Deaconess (University) Hospital (Norway); Department of Surgical Sciences, University of Bergen (Norway)), Email: jtgeit@online.no; Eikeland, Joakim (Department of Public Health and Primary Health Care, University of Bergen (Norway)); Rosland, Jan Henrik (Department of Public Health and Primary Health Care, University of Bergen (Norway); Sunniva Clinic for Palliative Care, Haraldsplass Deaconess (University) Hospital (Norway))

    2012-03-15

    Background. Whole-body MRI (WBMRI) has become an accessible method for detecting different types of pathologies both in the skeleton and the viscera, which may explain painful conditions, for example tumors and inflammation. Purpose. To assess a possible value of using WBMRI in order to improve palliative care. Material and Methods. Twenty patients (all eligible patients) admitted to the Department for Palliative Care were consecutively included in this study. They underwent a modified WBMRI, with fewer and shorter pulse sequences than in a standard WBMRI, to reduce patient stress. However, the patients' physicians were to exclude patients where little might be obtained and discomfort, distress, and pain could be induced. The treating physicians registered clinical utility directly after receiving the MRI report in a questionnaire. The registration was repeated after ended treatment. Results. Eighty percent had new findings detected, and 40% of the patients had a change in treatment due to the MRI result, mainly changes in analgesics and/or radiation therapy. Conclusion. The WBMRI helped the clinicians to improve treatment and a majority of the patients benefited from this. In eight patients the treatment was changed due to the results. The clinical value (utility) was indicated to be high

  3. GHz nuclear magnetic resonance

    Energy Technology Data Exchange (ETDEWEB)

    Cross, T.A.; Drobny, G.; Trewhella, J.

    1994-12-01

    For the past dozen years, 500- and 600-MHz spectrometers have become available in many laboratories. The first 600-MHz NMR spectrometer (at Carnegie Mellon University) was commissioned more than 15 years ago and, until 1994, represented the highest field available for high-resolution NMR. This year, we have witnessed unprecedented progress in the development of very high field magnets for NMR spectroscopy, including the delivery of the first commercial 750-MHz NMR spectrometers. In addition, NMR signals have been obtained from 20-Tesla magnets (850 MHz for {sup 1}H`s) at both Los Alamos National Laboratory and Florida State University in the NHMFL (National High Magnetic Field Laboratory). These preliminary experiments have been performed in magnets with 100-ppm homogeneity, but a 20-Tesla magnet developed for the NHMFL will be brought to field this year with a projected homogeneity of 0.1 ppm over a 1-cm-diam spherical volume.

  4. Principles of magnetic resonance imaging

    International Nuclear Information System (INIS)

    Mlynarik, V.; Tkac, I.; Srbecky, M.

    1995-01-01

    The aim of this review is to describe and explain the basic principles of magnetic resonance imaging. The first part of the text is devoted to the phenomenon of magnetic resonance (the interaction of RF magnetic field with the set of magnetic moments in the homogeneous magnetic field) and to relaxation processes. Then, the creation of MR image is described (slice selection, phase and frequency encoding of spatial information). The basic and the most frequently used techniques are explained (spin echo, gradient echo). The way the repetition and echo times influence the image quality and contrast (T1 or T2 weighing) is described. The part with the technical description of the MR equipment is included in the review. The MR imagination examination are compared with X-ray computer tomography technique

  5. Magnetic resonance imaging of the fetal brain.

    Science.gov (United States)

    Tee, L Mf; Kan, E Yl; Cheung, J Cy; Leung, W C

    2016-06-01

    This review covers the recent literature on fetal brain magnetic resonance imaging, with emphasis on techniques, advances, common indications, and safety. We conducted a search of MEDLINE for articles published after 2010. The search terms used were "(fetal OR foetal OR fetus OR foetus) AND (MR OR MRI OR [magnetic resonance]) AND (brain OR cerebral)". Consensus statements from major authorities were also included. As a result, 44 relevant articles were included and formed the basis of this review. One major challenge is fetal motion that is largely overcome by ultra-fast sequences. Currently, single-shot fast spin-echo T2-weighted imaging remains the mainstay for motion resistance and anatomical delineation. Recently, a snap-shot inversion recovery sequence has enabled robust T1-weighted images to be obtained, which is previously a challenge for standard gradient-echo acquisitions. Fetal diffusion-weighted imaging, diffusion tensor imaging, and magnetic resonance spectroscopy are also being developed. With multiplanar capabilities, superior contrast resolution and field of view, magnetic resonance imaging does not have the limitations of sonography, and can provide additional important information. Common indications include ventriculomegaly, callosum and posterior fossa abnormalities, and twin complications. There are safety concerns about magnetic resonance-induced heating and acoustic damage but current literature showed no conclusive evidence of deleterious fetal effects. The American College of Radiology guideline states that pregnant patients can be accepted to undergo magnetic resonance imaging at any stage of pregnancy if risk-benefit ratio to patients warrants that the study be performed. Magnetic resonance imaging of the fetal brain is a safe and powerful adjunct to sonography in prenatal diagnosis. It can provide additional information that aids clinical management, prognostication, and counselling.

  6. Appropriateness of computed tomography and magnetic resonance ...

    African Journals Online (AJOL)

    Introduction. Computed tomography (CT) and magnetic resonance imaging (MRI) are an essential part of modern healthcare. Marked increases in clinical demand for these imaging modalities are straining healthcare expenditure and threatening health system sustainability. The number of CT and MRI scans requested in ...

  7. SU-E-J-181: Magnetic Resonance Image-Guided Radiation Therapy Workflow: Initial Clinical Experience

    International Nuclear Information System (INIS)

    Green, O; Kashani, R; Santanam, L; Wooten, H; Li, H; Rodriguez, V; Hu, Y; Mutic, S; Hand, T; Victoria, J; Steele, C

    2014-01-01

    Purpose: The aims of this work are to describe the workflow and initial clinical experience treating patients with an MRI-guided radiotherapy (MRIGRT) system. Methods: Patient treatments with a novel MR-IGRT system started at our institution in mid-January. The system consists of an on-board 0.35-T MRI, with IMRT-capable delivery via doubly-focused MLCs on three 60 Co heads. In addition to volumetric MR-imaging, real-time planar imaging is performed during treatment. So far, eleven patients started treatment (six finished), ranging from bladder to lung SBRT. While the system is capable of online adaptive radiotherapy and gating, a conventional workflow was used to start, consisting of volumetric imaging for patient setup using visible tumor, evaluation of tumor motion outside of PTV on cine images, and real-time imaging. Workflow times were collected and evaluated to increase efficiency and evaluate feasibility of adding the adaptive and gating features while maintaining a reasonable patient throughput. Results: For the first month, physicians attended every fraction to provide guidance on identifying the tumor and an acceptable level of positioning and anatomical deviation. Average total treatment times (including setup) were reduced from 55 to 45 min after physician presence was no longer required and the therapists had learned to align patients based on soft-tissue imaging. Presently, the source strengths were at half maximum (7.7K Ci each), therefore beam-on times will be reduced after source replacement. Current patient load is 10 per day, with increase to 25 anticipated in the near future. Conclusion: On-board, real-time MRI-guided RT has been incorporated into clinical use. Treatment times were kept to reasonable lengths while including volumetric imaging, previews of tumor movement, and physician evaluation. Workflow and timing is being continuously evaluated to increase efficiency. In near future, adaptive and gating capabilities of the system will be

  8. Magnetic resonance in multiple sclerosis

    International Nuclear Information System (INIS)

    Scotti, G.; Caputo, D.; Cazzullo, C.L.

    1986-01-01

    Magnetic Resonance Imaging was performed in more than 200 patients with clinical suspicion or knowledge of Multiple Sclerosis. One hundred and forty-seven (60 males and 87 females) had MR evidence of multiple sclerosis lesions. The MR signal of demyelinating plaques characteristically has prolonged T1 and T2 relaxation times and the T2-weighted spin-echo sequences are generally superior to the T1-weighted images because the lesions are better visualized as areas of increased signal intensity. MR is also able to detect plaques in the brainstem, cerebellum and within the cervical spinal cord. MR appears to be an important, non-invasive method for the diagnosis of Multiple Sclerosis and has proven to be diagnostically superior to CT, evoked potentials (EP) and CSF examination. In a selected group of 30 patients, with the whole battery of the relevant MS studies, MR was positive in 100%, CT in 33,3%, EP in 56% and CSF examination in 60%. In patients clinically presenting only with signs of spinal cord involvement or optic neuritis or when the clinical presentation is uncertain MR has proven to be a very useful diagnostic tool for diagnosis of MS by demonstrating unsuspected lesions in the cerebral hemispheres. (orig.)

  9. Magnetic resonance lung function – a breakthrough for lung imaging and functional assessment? A phantom study and clinical trial

    Directory of Open Access Journals (Sweden)

    Rauh Manfred

    2006-08-01

    Full Text Available Abstract Background Chronic lung diseases are a major issue in public health. A serial pulmonary assessment using imaging techniques free of ionizing radiation and which provides early information on local function impairment would therefore be a considerably important development. Magnetic resonance imaging (MRI is a powerful tool for the static and dynamic imaging of many organs. Its application in lung imaging however, has been limited due to the low water content of the lung and the artefacts evident at air-tissue interfaces. Many attempts have been made to visualize local ventilation using the inhalation of hyperpolarized gases or gadolinium aerosol responding to MRI. None of these methods are applicable for broad clinical use as they require specific equipment. Methods We have shown previously that low-field MRI can be used for static imaging of the lung. Here we show that mathematical processing of data derived from serial MRI scans during the respiratory cycle produces good quality images of local ventilation without any contrast agent. A phantom study and investigations in 85 patients were performed. Results The phantom study proved our theoretical considerations. In 99 patient investigations good correlation (r = 0.8; p ≤ 0.001 was seen for pulmonary function tests and MR ventilation measurements. Small ventilation defects were visualized. Conclusion With this method, ventilation defects can be diagnosed long before any imaging or pulmonary function test will indicate disease. This surprisingly simple approach could easily be incorporated in clinical routine and may be a breakthrough for lung imaging and functional assessment.

  10. Clinical, magnetic resonance imaging, and histopathologic findings in 6 dogs with surgically resected extraparenchymal spinal cord hematomas.

    Science.gov (United States)

    Hague, D W; Joslyn, S; Bush, W W; Glass, E N; Durham, A C

    2015-01-01

    Extraparenchymal spinal cord hematoma has been described in veterinary medicine in association with neoplasia, intervertebral disk disease, and snake envenomation. There are rare reports of spontaneous extraparenchymal spinal cord hematoma formation with no known cause in human medicine. Multiple cases of spontaneous extraparenchymal spinal cord hematoma have not been described previously in veterinary medicine. To describe the signalment, clinical findings, magnetic resonance imaging (MRI) features, and surgical outcomes in histopathologically confirmed extraparenchymal spinal cord hematomas in dogs with no identified underlying etiology. Six dogs had MRI of the spinal cord, decompressive spinal surgery, and histopathologic confirmation of extraparenchymal spinal cord hematoma not associated with an underlying cause. Multi-institutional retrospective study. Six patients had spontaneous extraparenchymal spinal cord hematoma formation. MRI showed normal signal within the spinal cord parenchyma in all patients. All hematomas had T2-weighted hyperintensity and the majority (5/6) had no contrast enhancement. All dogs underwent surgical decompression and most patients (5/6) returned to normal or near normal neurologic function postoperatively. Follow-up of the patients (ranging between 921 and 1,446 days) showed no progression of neurologic clinical signs or any conditions associated with increased bleeding tendency. Before surgery and histopathology confirming extraparenchymal hematoma, the primary differential in most cases was neoplasia, based on the MRI findings. This retrospective study reminds clinicians of the importance of the combination of advanced imaging combined with histopathologic diagnosis. The prognosis for spontaneous spinal cord extraparenchymal hematoma with surgical decompression appears to be favorable in most cases. Copyright © 2015 by the American College of Veterinary Internal Medicine.

  11. Bifurcation magnetic resonance in films magnetized along hard magnetization axis

    Energy Technology Data Exchange (ETDEWEB)

    Vasilevskaya, Tatiana M., E-mail: t_vasilevs@mail.ru [Ulyanovsk State University, Leo Tolstoy 42, 432017 Ulyanovsk (Russian Federation); Sementsov, Dmitriy I.; Shutyi, Anatoliy M. [Ulyanovsk State University, Leo Tolstoy 42, 432017 Ulyanovsk (Russian Federation)

    2012-09-15

    We study low-frequency ferromagnetic resonance in a thin film magnetized along the hard magnetization axis performing an analysis of magnetization precession dynamics equations and numerical simulation. Two types of films are considered: polycrystalline uniaxial films and single-crystal films with cubic magnetic anisotropy. An additional (bifurcation) resonance initiated by the bistability, i.e. appearance of two closely spaced equilibrium magnetization states is registered. The modification of dynamic modes provoked by variation of the frequency, amplitude, and magnetic bias value of the ac field is studied. Both steady and chaotic magnetization precession modes are registered in the bifurcation resonance range. - Highlights: Black-Right-Pointing-Pointer An additional bifurcation resonance arises in a case of a thin film magnetized along HMA. Black-Right-Pointing-Pointer Bifurcation resonance occurs due to the presence of two closely spaced equilibrium magnetization states. Black-Right-Pointing-Pointer Both regular and chaotic precession modes are realized within bifurcation resonance range. Black-Right-Pointing-Pointer Appearance of dynamic bistability is typical for bifurcation resonance.

  12. Bifurcation magnetic resonance in films magnetized along hard magnetization axis

    International Nuclear Information System (INIS)

    Vasilevskaya, Tatiana M.; Sementsov, Dmitriy I.; Shutyi, Anatoliy M.

    2012-01-01

    We study low-frequency ferromagnetic resonance in a thin film magnetized along the hard magnetization axis performing an analysis of magnetization precession dynamics equations and numerical simulation. Two types of films are considered: polycrystalline uniaxial films and single-crystal films with cubic magnetic anisotropy. An additional (bifurcation) resonance initiated by the bistability, i.e. appearance of two closely spaced equilibrium magnetization states is registered. The modification of dynamic modes provoked by variation of the frequency, amplitude, and magnetic bias value of the ac field is studied. Both steady and chaotic magnetization precession modes are registered in the bifurcation resonance range. - Highlights: ► An additional bifurcation resonance arises in a case of a thin film magnetized along HMA. ► Bifurcation resonance occurs due to the presence of two closely spaced equilibrium magnetization states. ► Both regular and chaotic precession modes are realized within bifurcation resonance range. ► Appearance of dynamic bistability is typical for bifurcation resonance.

  13. Contrast-enhanced magnetic resonance imaging of pulmonary lesions: Description of a technique aiming clinical practice

    International Nuclear Information System (INIS)

    Koenigkam-Santos, Marcel; Optazaite, Elzbieta; Sommer, Gregor; Safi, Seyer; Heussel, Claus Peter; Kauczor, Hans-Ulrich

    2015-01-01

    To propose a technique for evaluation of pulmonary lesions using contrast-enhanced MRI; to assess morphological patterns of enhancement and correlate quantitative analysis with histopathology. Material and methods: Thirty-six patients were prospectively studied. Volumetric-interpolated T1W images were obtained during consecutive breath holds after bolus triggered contrast injection. Volume coverage of first three acquisitions was limited (higher temporal resolution) and last acquisition obtained at 4th min. Two radiologists individually evaluated the patterns of enhancement. Region-of-interest-based signal intensity (SI)-time curves were created to assess quantitative parameters. Results: Readers agreed moderately to substantially concerning lesions’ enhancement pattern. SI-time curves could be created for all lesions. In comparison to benign, malignant lesions showed higher values of maximum enhancement, early peak, slope and 4th min enhancement. Early peak >15% showed 100% sensitivity to detect malignancy, maximum enhancement >40% showed 100% specificity. Conclusions: The proposed technique is robust, simple to perform and can be applied in clinical scenario. It allows visual evaluation of enhancement pattern/progression together with creation of SI-time curves and assessment of derived quantitative parameters. Perfusion analysis was highly sensitive to detect malignancy, in accordance to what is recommended by most recent guidelines on imaging evaluation of pulmonary lesions

  14. Magnetic resonance imaging in perinatal brain injury: clinical presentation, lesions and outcome

    Energy Technology Data Exchange (ETDEWEB)

    Rutherford, Mary; Ward, Phil; Allsop, Joanna; Counsell, Serena [Imperial College London, Hammersmith Hospital, Robert Steiner MR Unit, Imaging Sciences Department, Clinical Sciences Centre, London (United Kingdom); Srinivasan, Latha; Dyet, Leigh; Cowan, Frances [Imperial College, Hammersmith Hospital, Department of Paediatrics, Imaging Sciences Department, Clinical Sciences Centre, London (United Kingdom)

    2006-07-15

    Neonatal MR imaging is invaluable in assessing the term born neonate who presents with an encephalopathy. Successful imaging requires adaptations to both the hardware and the sequences used for adults. The perinatal and postnatal details often predict the pattern of lesions sustained and are essential for correct interpretation of the imaging findings, but additional or alternative diagnoses in infants with apparent hypoxic ischaemic encephalopathy should always be considered. Perinatally acquired lesions are usually at their most obvious between 1 and 2 weeks of age. Very early imaging (<3 days) may be useful to make management decisions in ventilated neonates, but abnormalities may be subtle at that stage. Diffusion-weighted imaging is clinically useful for the early identification of ischaemic white matter in the neonatal brain but is less reliable in detecting lesions within the basal ganglia and thalami. The pattern of lesions seen on MRI can predict neurodevelopmental outcome. Additional useful information may be obtained by advanced techniques such as MR angiography, venography and perfusion-weighted imaging. Serial imaging with quantification of both structure size and tissue damage provides invaluable insights into perinatal brain injury. (orig.)

  15. Contrast-enhanced magnetic resonance imaging of pulmonary lesions: Description of a technique aiming clinical practice

    Energy Technology Data Exchange (ETDEWEB)

    Koenigkam-Santos, Marcel, E-mail: marcelk46@yahoo.com.br [Department of Diagnostic and Interventional Radiology, University of Heidelberg, Im Neuenheimer Feld 110, 69120 Heidelberg (Germany); Radiology Department, German Cancer Research Center (Deutsches Krebsforschungszentrum – DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany); Department of Radiology, University Hospital of the School of Medicine of Ribeirao Preto, University of Sao Paulo, Avenida Bandeirantes 3900, Campus Universitario Monte Alegre, 14048 900 Ribeirao Preto, Sao Paulo (Brazil); Optazaite, Elzbieta, E-mail: optazaite@andrulis.eu [Diagnostic and Interventional Radiology with Nuclear Medicine, Chest Clinic (Thoraxklinik), University of Heidelberg, Amalienstraße 5, 69126 Heidelberg (Germany); Sommer, Gregor, E-mail: gregor.sommer@usb.ch [Clinic of Radiology and Nuclear Medicine, University Hospital Basel, Petersgraben 4, CH-4031 Basel (Switzerland); Safi, Seyer, E-mail: seyer.safi@gmail.com [Surgery Department, Chest Clinic (Thoraxklinik), University of Heidelberg, Amalienstraße 5, 69126 Heidelberg (Germany); Heussel, Claus Peter, E-mail: heussel@uni-heidelberg.de [Diagnostic and Interventional Radiology with Nuclear Medicine, Chest Clinic (Thoraxklinik), University of Heidelberg, Amalienstraße 5, 69126 Heidelberg (Germany); Translational Lung Research Center (TLRC), Member of the German Center for Lung Research (DZL), Im Neuenheimer Feld 350, 69120 Heidelberg (Germany); Kauczor, Hans-Ulrich, E-mail: hans-ulrich.kauczor@med.uni-heidelberg.de [Department of Diagnostic and Interventional Radiology, University of Heidelberg, Im Neuenheimer Feld 110, 69120 Heidelberg (Germany); Translational Lung Research Center (TLRC), Member of the German Center for Lung Research (DZL), Im Neuenheimer Feld 350, 69120 Heidelberg (Germany); and others

    2015-01-15

    To propose a technique for evaluation of pulmonary lesions using contrast-enhanced MRI; to assess morphological patterns of enhancement and correlate quantitative analysis with histopathology. Material and methods: Thirty-six patients were prospectively studied. Volumetric-interpolated T1W images were obtained during consecutive breath holds after bolus triggered contrast injection. Volume coverage of first three acquisitions was limited (higher temporal resolution) and last acquisition obtained at 4th min. Two radiologists individually evaluated the patterns of enhancement. Region-of-interest-based signal intensity (SI)-time curves were created to assess quantitative parameters. Results: Readers agreed moderately to substantially concerning lesions’ enhancement pattern. SI-time curves could be created for all lesions. In comparison to benign, malignant lesions showed higher values of maximum enhancement, early peak, slope and 4th min enhancement. Early peak >15% showed 100% sensitivity to detect malignancy, maximum enhancement >40% showed 100% specificity. Conclusions: The proposed technique is robust, simple to perform and can be applied in clinical scenario. It allows visual evaluation of enhancement pattern/progression together with creation of SI-time curves and assessment of derived quantitative parameters. Perfusion analysis was highly sensitive to detect malignancy, in accordance to what is recommended by most recent guidelines on imaging evaluation of pulmonary lesions.

  16. A clinical study of brainstem infarction identified on magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Masaki; Takahashi, Akira (Nagoya Univ. (Japan). Faculty of Medicine); Arahata, Yutaka; Motegi, Yoshimasa; Furuse, Masahiro

    1993-04-01

    We conducted a clinical study of 155 cases that were confirmed to have brainstem infarctions on MRI (T[sub 1]-weighted image showed a low signal and T[sub 2]-weighted image showed a high signal, measuring in excess of 2 x 2 mm). The majority of the brainstem infarction was located in the pontine base in 132 cases (85.2%). Of these, 19 cases had double lesions including infarctions in the pontine base. Second infarctions frequently occurred in the cerebral peduncle or medical medulla oblongata, unilateral to the pontine infarctions. In addition to 98 symptomatic cases, there were 57 cases of 'asymptomatic' brainstem infarction. They comprised 24 cases accompanying other symptomatic cerebrovascular diseases in the supratentorium and 33 cases of transient subjective complaints such as headache or vertigo-dizziness. Complication by supratentorial infarctions was significantly frequent in cases of brainstem infarction (p<0.001), 122 of 155 cases (78.7%), especially in the pontine base (88.6%); while in the control cases (without brainstem infarction) only 65 of 221 cases (29.4%). These findings are considered to show the widespread progress of arteriosclerosis in brainstem infarction, especially in ones in the pontine base. (author).

  17. Non-cardiovascular findings in clinical cardiovascular magnetic resonance imaging in children

    International Nuclear Information System (INIS)

    Ghadimi Mahani, Maryam; Morani, Ajaykumar C.; Lu, Jimmy C.; Dorfman, Adam L.; Fazeli Dehkordy, Soudabeh; Jeph, Sunil; Agarwal, Prachi P.

    2016-01-01

    With increasing use of pediatric cardiovascular MRI, it is important for all imagers to become familiar with the spectrum of non-cardiovascular imaging findings that can be encountered. This study aims to ascertain the prevalence and nature of these findings in pediatric cardiovascular MRIs performed at our institution. We retrospectively evaluated reports of all cardiovascular MRI studies performed at our institute from January 2008 to October 2012 in patients younger than18 years. Most studies (98%) were jointly interpreted by a pediatric cardiologist and a radiologist. We reviewed the electronic medical records of all cases with non-cardiovascular findings, defined as any imaging finding outside the cardiovascular system. Non-cardiovascular findings were classified into significant and non-significant, based on whether they were known at the time of imaging or they required additional workup or a change in management. In 849 consecutive studies (mean age 9.7 ± 6.3 years), 145 non-cardiovascular findings were found in 140 studies (16.5% of total studies). Overall, 51.0% (74/145) of non-cardiovascular findings were in the abdomen, 30.3% (44/145) were in the chest, and 18.6% (27/145) were in the spine. A total of 19 significant non-cardiovascular findings were observed in 19 studies in individual patients (2.2% of total studies, 47% male, mean age 5.9 ± 6.7 years). Significant non-cardiovascular findings included hepatic adenoma, arterially enhancing focal liver lesions, asplenia, solitary kidney, pelvicaliectasis, renal cystic diseases, gastric distention, adrenal hemorrhage, lung hypoplasia, air space disease, bronchial narrowing, pneumomediastinum and retained surgical sponge. Non-cardiovascular findings were seen in 16.5% of cardiovascular MRI studies in children, of which 2.2% were clinically significant findings. Prevalence and nature of these non-cardiovascular findings are different from those reported in adults. Attention to these findings is important

  18. Non-cardiovascular findings in clinical cardiovascular magnetic resonance imaging in children

    Energy Technology Data Exchange (ETDEWEB)

    Ghadimi Mahani, Maryam [University of Michigan Health System, C.S. Mott Children' s Hospital, Department of Radiology, Section of Pediatric Radiology, Ann Arbor, MI (United States); Morani, Ajaykumar C. [The University of Texas MD Anderson Cancer Center, Department of Diagnostic Radiology, Houston, TX (United States); Lu, Jimmy C.; Dorfman, Adam L. [University of Michigan Health System, C.S. Mott Children' s Hospital, Department of Pediatrics and Communicable Diseases, Division of Pediatric Cardiology, Ann Arbor, MI (United States); Fazeli Dehkordy, Soudabeh [University of Michigan Health System, C.S. Mott Children' s Hospital, Department of Radiology, Section of Pediatric Radiology, Ann Arbor, MI (United States); Providence Hospital and Medical Centers, Department of Graduate Medical Education, Southfield, MI (United States); Jeph, Sunil [The University of Texas MD Anderson Cancer Center, Department of Diagnostic Radiology, Houston, TX (United States); Geisinger Medical Center, Department of Radiology, Danville, PA (United States); Agarwal, Prachi P. [University of Michigan Health System, Department of Radiology, Division of Cardiothoracic Radiology, Ann Arbor, MI (United States)

    2016-04-15

    With increasing use of pediatric cardiovascular MRI, it is important for all imagers to become familiar with the spectrum of non-cardiovascular imaging findings that can be encountered. This study aims to ascertain the prevalence and nature of these findings in pediatric cardiovascular MRIs performed at our institution. We retrospectively evaluated reports of all cardiovascular MRI studies performed at our institute from January 2008 to October 2012 in patients younger than18 years. Most studies (98%) were jointly interpreted by a pediatric cardiologist and a radiologist. We reviewed the electronic medical records of all cases with non-cardiovascular findings, defined as any imaging finding outside the cardiovascular system. Non-cardiovascular findings were classified into significant and non-significant, based on whether they were known at the time of imaging or they required additional workup or a change in management. In 849 consecutive studies (mean age 9.7 ± 6.3 years), 145 non-cardiovascular findings were found in 140 studies (16.5% of total studies). Overall, 51.0% (74/145) of non-cardiovascular findings were in the abdomen, 30.3% (44/145) were in the chest, and 18.6% (27/145) were in the spine. A total of 19 significant non-cardiovascular findings were observed in 19 studies in individual patients (2.2% of total studies, 47% male, mean age 5.9 ± 6.7 years). Significant non-cardiovascular findings included hepatic adenoma, arterially enhancing focal liver lesions, asplenia, solitary kidney, pelvicaliectasis, renal cystic diseases, gastric distention, adrenal hemorrhage, lung hypoplasia, air space disease, bronchial narrowing, pneumomediastinum and retained surgical sponge. Non-cardiovascular findings were seen in 16.5% of cardiovascular MRI studies in children, of which 2.2% were clinically significant findings. Prevalence and nature of these non-cardiovascular findings are different from those reported in adults. Attention to these findings is important

  19. Study on the clinical usefulness of magnetic resonance imaging in cases of multiple cerebral infarction

    International Nuclear Information System (INIS)

    Miyashita, Kotaro

    1991-01-01

    The clinical significance of MRI in thrombotic multiple cerebral infarction was examined in 9 patients having recent lacunar stroke. Recent infarct was identified on Gd-enhanced MRI in 4 patients. For patients multiple small infarction, Gd-enhanced MRI made it possible to differentiate recent from other lesions. To clarify the significance of periventricular high intensity lesion (PVH) on T2-weighted MRI, hemodynamic and neuropsychologic examinations were carried out in 41 patients with multiple cerebral infarction. All the patients had PVH, which was classified into three grades as follows: grade I (n=16) showing only a thin high intensity band along the body of lateral ventricles; grade 2 (n=15) showing a definite high intensity area around the lateral ventricles; grade 3 (n=10) showing diffuse thick and irregular foci around the whole ventricle. In these patients, rCBF was measured by 133 Xe inhalation methods. Initial slope index was significantly higher in patients with grade 3 than those with grade I. Mini-mental state test score was significantly higher in patients with grade l than those with grade 2 and 3. Progression of PVH may be related with the reduction of the cerebral circulation and mental function in cases of multiple cerebral infarction. Ischemic and hemorrhagic lesions can be distinguished by MRI, because old intracerebral hemorrhage appear as hypointensity areas with or without hyperintensity area on T2w images. In 92 patients with multiple infarction, MRI was used to evaluate the incidence and distribution of coexisting old intracerebral hemorrhage. Old hemorrhage were found in 15 patients (16.3%). locating the site where hypertensive hemorrhage commonly occurred. High-field MRI is useful for assessing the coexistence of hemorrhage in hypertensive patients with multiple cerebral infarction. (N.K.)

  20. Cardiovascular Magnetic Resonance Imaging—Incremental Value in a Series of 361 Patients Demonstrating Cost Savings and Clinical Benefits: An Outcome-Based Study

    Science.gov (United States)

    Hegde, Vinayak A; Biederman, Robert WW; Mikolich, J Ronald

    2017-01-01

    BACKGROUND This study was designed to assess the clinical impact and cost-benefit of cardiovascular magnetic resonance imaging (CMR). In the face of current health care cost concerns, cardiac imaging modalities have come under focused review. Data related to CMR clinical impact and cost-benefit are lacking. METHODS AND RESULTS Retrospective review of 361 consecutive patients (pts) who underwent CMR exams was conducted. Indications for CMR were tabulated for appropriateness criteria. Components of the CMR exam were identified along with evidence of clinical impact. The cost of each CMR exam was ascertained along with cost savings attributable to the CMR exam for calculation of an incremental cost-effectiveness ratio. A total of 354 of 361 pts (98%) had diagnostic quality studies. Of the 361 pts, 350 (97%) had at least 1 published Appropriateness Criterion for CMR. A significant clinical impact attributable to CMR exam results was observed in 256 of 361 pts (71%). The CMR exam resulted in a new diagnosis in 69 of 361 (27%) pts. Cardiovascular magnetic resonance imaging results avoided invasive procedures in 38 (11%) pts and prevented additional diagnostic testing in 26 (7%) pts. Comparison of health care savings using CMR as opposed to current standards of care showed a net cost savings of $833 037, ie, per patient cost savings of $2308. CONCLUSIONS Cardiovascular magnetic resonance imaging provides diagnostic image quality in >98% of cases. Cardiovascular magnetic resonance imaging findings have documentable clinical impact on patient management in 71% of pts undergoing the exam, in a cost beneficial manner. PMID:28579858

  1. Cardiovascular Magnetic Resonance Imaging—Incremental Value in a Series of 361 Patients Demonstrating Cost Savings and Clinical Benefits: An Outcome-Based Study

    Directory of Open Access Journals (Sweden)

    Vinayak A Hegde

    2017-05-01

    Full Text Available Background: This study was designed to assess the clinical impact and cost-benefit of cardiovascular magnetic resonance imaging (CMR. In the face of current health care cost concerns, cardiac imaging modalities have come under focused review. Data related to CMR clinical impact and cost-benefit are lacking. Methods and Results: Retrospective review of 361 consecutive patients (pts who underwent CMR exams was conducted. Indications for CMR were tabulated for appropriateness criteria. Components of the CMR exam were identified along with evidence of clinical impact. The cost of each CMR exam was ascertained along with cost savings attributable to the CMR exam for calculation of an incremental cost-effectiveness ratio. A total of 354 of 361 pts (98% had diagnostic quality studies. Of the 361 pts, 350 (97% had at least 1 published Appropriateness Criterion for CMR. A significant clinical impact attributable to CMR exam results was observed in 256 of 361 pts (71%. The CMR exam resulted in a new diagnosis in 69 of 361 (27% pts. Cardiovascular magnetic resonance imaging results avoided invasive procedures in 38 (11% pts and prevented additional diagnostic testing in 26 (7% pts. Comparison of health care savings using CMR as opposed to current standards of care showed a net cost savings of $833 037, ie, per patient cost savings of $2308. Conclusions: Cardiovascular magnetic resonance imaging provides diagnostic image quality in >98% of cases. Cardiovascular magnetic resonance imaging findings have documentable clinical impact on patient management in 71% of pts undergoing the exam, in a cost beneficial manner.

  2. The Use of Cardiac Magnetic Resonance in Patients with Suspected Coronary Artery Disease: A Clinical Practice Perspective

    OpenAIRE

    Chang, Sung-A; Kim, Raymond J.

    2016-01-01

    Cardiac magnetic resonance imaging (CMR) is a useful diagnostic imaging modality in patients with known or suspected coronary artery disease (CAD). It provides unique information not available from other modalities, however, it is complex. CMR is not a single technique. Instead, it consists of multiple distinct techniques and a lack of understanding of which techniques to perform and how to interpret the findings in combination limits its efficacy and widespread use. Conversely, its multipara...

  3. Multispecialty retrospective review of the clinical utility of pelvic magnetic resonance imaging in the setting of pelvic pain.

    Science.gov (United States)

    Moore, John R; Pathak, Ram A; Snowden, Caroline; Bolan, Candice W; Young, Paul R; Broderick, Gregory A

    2017-12-01

    Pelvic pain is a common complaint, and management of it is often difficult. We sought to evaluate the utility of magnetic resonance imaging (MRI) in the diagnosis of male pelvic pain. Though MRIs are commonly ordered to evaluate pelvic pain, there are very few studies obtaining the efficacy of pelvic MRI in determining a definitive diagnosis. The primary aim of our study was to evaluate the clinical utility of pelvic MRI for a diagnosis code that included pain. After receiving institutional review board approval, a retrospective study was performed of all pelvic MRIs completed at our institution from January 2, 2010 to December 31, 2014. These were further delineated into ordering providers by specialty and urology-specific International Classification of Diseases, Ninth Revision (ICD-9) code diagnoses (male pelvic pain, prostatitis, groin pain, scrotal pain, testicular pain, and penile pain). Clinical utility was defined as positive if MRI findings resulted in a change in management. Subanalysis was performed on patients with an ICD-9 co-diagnosis of previous oncologic concern. A total of 2,643 pelvic MRIs were ordered at our institution over a 5-year period. Of these, 597 pelvic MRIs (23%) were ordered for a diagnosis code that included pain (hip pain, rectal pain, joint pain, penile pain, scrotal pain, male pelvic pain and orchitis). Total utility for MRIs to find anatomic abnormalities potentially responsible for the present pain was 34% (205/597). When ordered by urologic providers, utility was 23%. Oncologists represented the highest positivity rate at 57%. Chronic pelvic pain is a multispecialty complaint that is difficult to treat. We were surprised to find the large number of both specialists and generalists invested in the management of pelvic pain. The increasing availability of MRI technology makes it a likely candidate to test for a clinically significant anatomic reason for pain. Though MRI is a test with minimal adverse effect and no increased risk

  4. Migraine and magnetic resonance spectroscopy

    DEFF Research Database (Denmark)

    Younis, Samaira; Hougaard, Anders; Vestergaard, Mark B.

    2017-01-01

    Purpose of review: To present an updated and streamlined overview of the metabolic and biochemical aspect of the migraine pathophysiology based on findings from phosphorous (31P) and hydrogen (1H) magnetic resonance spectroscopy (MRS) studies. Recent findings: Despite of the variation in the meth......Purpose of review: To present an updated and streamlined overview of the metabolic and biochemical aspect of the migraine pathophysiology based on findings from phosphorous (31P) and hydrogen (1H) magnetic resonance spectroscopy (MRS) studies. Recent findings: Despite of the variation...

  5. Magnetic resonance imaging of hypophysis

    International Nuclear Information System (INIS)

    Malla Huesh, I. V.

    2016-01-01

    nuclei and sulci. FLAIR - sequences with its advantage in suppressing the signal from the cerebrospinal fluid is useful in case of meningeal involvement in hypophysitis. DWI is essential in case of ischemia, apoplexy and associated necrotic changes. Contrast medium application is not compulsory, but it increases the sensitivity of the method, especially in young patients. The contrast used is Gadolinium, applied according to the body weight. After contrast application the gland enhances homogeneously. MR-methods made are responsible for throwing light upon the normal images of the pituitary gland from the neonatal patients to adults, explaining the malformative and rare conditions, leading to disturbances in the hypothalamic-pituitary axis. The most common reason for pathologic conditions in the hypothalamic-pituitary axis remain the adenomas. MR-imaging is the method of choice to rule out a suspected formation in the sellar area. Small adenomas with size around 3mm are now detectable with the use of equipment with high strength of magnetic field. Authors agree on the fact the secreting and nonsecreting adenomas need a thorough MR-follow up in time, especially the nonsecreting ones that are usually detected accidentally. In the era before the multislice diagnostic imaging the pathologies in the hypothalamic-pituitary axis were difficult to assess. The introduction of the new methods of investigation made the diagnosis of such conditions achievable. Magnetic resonance imaging is convenient, informative and clinically applicable for detecting hypothalamic-pituitary axis. However there is no agreement how the MR-protocol should be carried out. MR with high magnetic field is an essential tool in obtaining images with better quality, higher diagnostic value and the opportunity for performing sequences in thin slices and reconstructions in different planes. Key words: Magnetic Resonance Imaging. Hypophysis. 3TESLA

  6. Clinical utility of high b-value diffusion-weighted magnetic resonance imaging in post-resuscitative encephalopathy

    Energy Technology Data Exchange (ETDEWEB)

    Kano, Hitoshi; Danjou, Wataru; Yamazaki, Kei [Sapporo City General Hospital (Japan)] (and others)

    2002-03-01

    It is very important to estimate brain functional capacity immediately after successful cardiopulmonary resuscitation (CPR) to determine subsequent treatment strategy and to elucidate the pathophysiology of patients with post-resuscitative encephalopathy. However, computed tomography scanning, electric encephalography and conventional magnetic resonance imaging do not contribute significantly to the assessment of brain functions immediately after CPR. Recently, diffusion-weighted magnetic resonance imaging (DW-MRI) has been applied to the patients with post-resuscitative encephalopathy. However, no papers have described serial clinical and repeated DW-MRI studies of patients during the acute phase of post-resuscitative encephalopathy. Moreover, in some cases, high signal intensity in the cortex after CPR is indistinguishable from normal cortex. Thus, we tried to apply high b-value DW-MRI to estimate the brain function of patients with post-resuscitative encephalopathy. This study was performed on 11 patients with post-resuscitative encephalopathy and 5 healthy volunteers as controls. DW-MRI was performed using GYROSCAN 1.5 Tesla MR imager (Philips) with single-shot echo-planner imaging sequences performed 3 times, first within 24 hours after CPR, second between day 3 to 6, and third more than 7 days after CPR. And we tested the usefulness of DW-MRI at 800, 1000, 1500, 2000 and 3000 in b value. Five patients survived, one fully recovered and four remained in a vegetative state. The other six died with clinical brain death. The first DW-MRI revealed in high signal intensity in the frontal and the parietal lobes in all patients who eventually progressed to a vegetative state or brain death. This result was much more wide-spread in the latter patients, while it was never seen in the patients who recovered fully. The high signal intensity areas increased in follow-up DW-MRI studies. The signal intensity remained high in some parts, while it decreased in other parts with

  7. Clinical utility of high b-value diffusion-weighted magnetic resonance imaging in post-resuscitative encephalopathy

    International Nuclear Information System (INIS)

    Kano, Hitoshi; Danjou, Wataru; Yamazaki, Kei

    2002-01-01

    It is very important to estimate brain functional capacity immediately after successful cardiopulmonary resuscitation (CPR) to determine subsequent treatment strategy and to elucidate the pathophysiology of patients with post-resuscitative encephalopathy. However, computed tomography scanning, electric encephalography and conventional magnetic resonance imaging do not contribute significantly to the assessment of brain functions immediately after CPR. Recently, diffusion-weighted magnetic resonance imaging (DW-MRI) has been applied to the patients with post-resuscitative encephalopathy. However, no papers have described serial clinical and repeated DW-MRI studies of patients during the acute phase of post-resuscitative encephalopathy. Moreover, in some cases, high signal intensity in the cortex after CPR is indistinguishable from normal cortex. Thus, we tried to apply high b-value DW-MRI to estimate the brain function of patients with post-resuscitative encephalopathy. This study was performed on 11 patients with post-resuscitative encephalopathy and 5 healthy volunteers as controls. DW-MRI was performed using GYROSCAN 1.5 Tesla MR imager (Philips) with single-shot echo-planner imaging sequences performed 3 times, first within 24 hours after CPR, second between day 3 to 6, and third more than 7 days after CPR. And we tested the usefulness of DW-MRI at 800, 1000, 1500, 2000 and 3000 in b value. Five patients survived, one fully recovered and four remained in a vegetative state. The other six died with clinical brain death. The first DW-MRI revealed in high signal intensity in the frontal and the parietal lobes in all patients who eventually progressed to a vegetative state or brain death. This result was much more wide-spread in the latter patients, while it was never seen in the patients who recovered fully. The high signal intensity areas increased in follow-up DW-MRI studies. The signal intensity remained high in some parts, while it decreased in other parts with

  8. Clinical utility of ultrasound versus magnetic resonance imaging for deciding to proceed with uterine artery embolization for presumed symptomatic fibroids

    International Nuclear Information System (INIS)

    Rajan, D.K.; Margau, R.; Kroll, R.R.; Simons, M.E.; Tan, K.T.; Jaskolka, J.D.; Kachura, J.R.; Sniderman, K.W.; Beecroft, J.R.; Haider, M.

    2011-01-01

    Aim: To compare the diagnostic utility of pelvic ultrasound (US) and magnetic resonance imaging (MRI) on the clinical decision to proceed with uterine artery embolization (UAE). Materials and methods: Over 2 years, 180 consecutive women (mean age 43) sought consultation for UAE, 116 underwent pelvic US and MRI before possible UAE. US was performed prior to MRI. Imaging was analysed for leiomyoma quantity, size and location, uterine volume, and the presence of potential contraindications to UAE. Discrepancies between imaging methods and cases where discrepancies could have altered management, were recorded. Results: For the 116 patients who completed imaging, the average uterine volume was 701 cm 3 using MRI versus 658 cm 3 using US (p = 0.48). The average dominant leiomyoma volume was 292 cm 3 using MRI versus 253 cm 3 using US (p = 0.16). In 14 (12.1%) patients US did not correctly quantify or localize leiomyomas compared with MRI (p = 0.0005). Thirteen patients did not undergo UAE (patient preference n = 9, pre-procedural imaging findings n = 4). In the four cases where UAE was not performed due to imaging findings, relevant findings were all diagnosed by MRI compared with two by US (p = 0.5). The two cases not detected by ultrasound were adenomyosis and a pedunculate subserosal leiomyoma. Of the 103 patients who underwent UAE, 14 were treated (without complication) despite the presence of a relative contraindication; all 14 relative contraindications were identified by MRI compared with 13 by US (p = 1.0). Conclusion: MRI is more accurate than US for characterizing uterine leiomyomas. In a small but statistically insignificant number of cases, MRI identified findings that were missed by US, which changed management. For patients that are unsuitable to be assessed with MRI, ultrasound alone is sufficient for pre-UAE assessment.

  9. Clinical utility of ultrasound versus magnetic resonance imaging for deciding to proceed with uterine artery embolization for presumed symptomatic fibroids

    Energy Technology Data Exchange (ETDEWEB)

    Rajan, D.K., E-mail: dheeraj.rajan@uhn.on.c [Department of Medical Imaging, University of Toronto (Canada); Departments of Vascular and Interventional Radiology, University Health Network and Mount Sinai Hospitals, Toronto (Canada); Margau, R. [Department of Medical Imaging, North York General Hospital, Toronto (Canada); Kroll, R.R. [Faculty of Social Science, University of Western Ontario, Toronto, Ontario (Canada); Simons, M.E.; Tan, K.T.; Jaskolka, J.D.; Kachura, J.R.; Sniderman, K.W.; Beecroft, J.R. [Department of Medical Imaging, University of Toronto (Canada); Departments of Vascular and Interventional Radiology, University Health Network and Mount Sinai Hospitals, Toronto (Canada); Haider, M. [Department of Medical Imaging, University of Toronto (Canada)

    2011-01-15

    Aim: To compare the diagnostic utility of pelvic ultrasound (US) and magnetic resonance imaging (MRI) on the clinical decision to proceed with uterine artery embolization (UAE). Materials and methods: Over 2 years, 180 consecutive women (mean age 43) sought consultation for UAE, 116 underwent pelvic US and MRI before possible UAE. US was performed prior to MRI. Imaging was analysed for leiomyoma quantity, size and location, uterine volume, and the presence of potential contraindications to UAE. Discrepancies between imaging methods and cases where discrepancies could have altered management, were recorded. Results: For the 116 patients who completed imaging, the average uterine volume was 701 cm{sup 3} using MRI versus 658 cm{sup 3} using US (p = 0.48). The average dominant leiomyoma volume was 292 cm{sup 3} using MRI versus 253 cm{sup 3} using US (p = 0.16). In 14 (12.1%) patients US did not correctly quantify or localize leiomyomas compared with MRI (p = 0.0005). Thirteen patients did not undergo UAE (patient preference n = 9, pre-procedural imaging findings n = 4). In the four cases where UAE was not performed due to imaging findings, relevant findings were all diagnosed by MRI compared with two by US (p = 0.5). The two cases not detected by ultrasound were adenomyosis and a pedunculate subserosal leiomyoma. Of the 103 patients who underwent UAE, 14 were treated (without complication) despite the presence of a relative contraindication; all 14 relative contraindications were identified by MRI compared with 13 by US (p = 1.0). Conclusion: MRI is more accurate than US for characterizing uterine leiomyomas. In a small but statistically insignificant number of cases, MRI identified findings that were missed by US, which changed management. For patients that are unsuitable to be assessed with MRI, ultrasound alone is sufficient for pre-UAE assessment.

  10. Analysis of the response of PVA-GTA Fricke-gel dosimeters with clinical magnetic resonance imaging

    Science.gov (United States)

    Collura, Giorgio; Gallo, Salvatore; Tranchina, Luigi; Abbate, Boris Federico; Bartolotta, Antonio; d'Errico, Francesco; Marrale, Maurizio

    2018-01-01

    Fricke gel dosimeters produced with a matrix of Poly-vinyl alcohol (PVA) cross-linked with glutaraldehyde (GTA) were analyzed with magnetic resonance imaging (MRI). Previous studies based on spectrophotometry showed valuable dosimetric features of these gels in terms of X-ray sensitivity and diffusion of the ferric ions produced after irradiation. In this study, MRI was performed on the gels at 1.5 T with a clinical scanner in order to optimize the acquisition parameters and obtain high contrast between irradiated and non-irradiated samples. The PVA gels were found to offer good linearity in the range of 0-10 Gy and a stable signal for several hours after irradiation. The sensitivity was about 40% higher compared to gels produced with agarose as gelling agent. The effect of xylenol orange (XO) on the MRI signal was also investigated: gel dosimeters made without XO show higher sensitivity to x-rays than those made with XO. The dosimetric accuracy of the 3D gels was investigated by comparing their MRI response to percentage depth dose and transversal dose profile measurements made with an ionization chamber in a water phantom. The comparison of PVA-GTA gels with and without XO showed that the chelating agent reduces the MRI sensitivity of the gels. Depth-dose and transversal dose profiles acquired by PVA-GTA gels without XO are more accurate and consistent with the ionization chamber data. However, diffusion effects hinder accurate measurements in the steep dose gradient regions and they should be further reduced by modifying the gel matrix and/or by minimizing the delay between irradiation and imaging.

  11. Distal border fragments of the equine navicular bone: association between magnetic resonance imaging characteristics and clinical lameness

    Science.gov (United States)

    Yorke, Elizabeth H.; Judy, Carter E.; Saveraid, Travis C.; McGowan, Conor P.; Caldwell, Fred J.

    2014-01-01

    Distal border fragments of the navicular bone are increasingly being detected due to the improved capabilities of magnetic resonance imaging (MRI), but their clinical significance remains unclear. The purpose of this retrospective study was to describe the location, size, and frequency of fragments in a cohort of horses presented for MRI of the foot and to compare MRI findings with severity of lameness. Archived MRI studies and medical records were searched from March 2006 to June 2008. Horses were included if a distal border fragment of the navicular bone was visible in MRI scans. Confidence interval comparisons and linear regression analyses were used to test hypotheses that fragments were associated with lameness and lameness severity was positively correlated with fragment volume and biaxial location. A total of 453 horses (874 limbs) were included. Fragments were identified in 60 horses (13.25%) and 90 limbs (10.3%). Fifty percent of the horses had unilateral fragments and 50% had bilateral fragments. Fragments were located at the lateral (62.2%), medial (8.89%), or medial and lateral (28.9%) angles of the distal border of the navicular bone. There was no increased probability of being categorized as lame if a fragment was present. There was no significant difference in fragment volume across lameness severity categorizations. Confidence intervals indicated a slightly increased probability of being classified as lame if both medial and lateral fragments were present. Findings indicated that distal border fragments of the navicular bone in equine MRI studies are unlikely to be related to existing lameness.

  12. Clinical diagnostic study by means of magnetic resonance imaging for lesions of the major salivary gland region

    International Nuclear Information System (INIS)

    Iihama, Tsuyoshi; Mataga, Izumi; Kato, Joji

    1994-01-01

    The diagnostic value of magnetic resonance imaging (MRI) for lesions situated in the major salivary glands was clinically discussed in this study. A total of 46 patients with salivary gland disorders treated in our department over the past five years were assessed by mean of MRI, and in 11 patients the findings were compared with the histopathological features of lesions sectioned at the same level postoperatively. In addition, preliminary investigations to introduce a new qualitative diagnostic procedure for estimation of salivary gland function in geriatric patients were attempted. In this investigation, T 1 and T 2 values, and signal intensity ratios of the submandibular gland were measured in elderly patients complaining of dry mouth and in healthy controls. Likewise, salivary gland function was examined by taste stimulation induced by applying citric acid to the tongue surface just before starting MRI. MRI clearly demonstrated lesions in the salivary glands. The histopathological diagnosis could not be accurately predicted by signal intensity. However, benign tumors showed higher intensity signals than did malignant tumors on T 2 -weighted images. Cystic lesions could be differentiated from tumors by signal intensity. Histopathological features of salivary gland tumors corresponded to the MRI signal intensity. Relaxation times of T 1 and T 2 values and signal intensity in each major salivary gland were diminished in elderly patients in a resting condition. Only T 1 values in healthy subjects remarkably responded to taste stimulation. These results suggest that MRI is useful and beneficial not only in the qualitative diagnosis of tumors arising from salivary glands but also in the estimation of salivary gland function. MRI should therefore be included in routine diagnostic examinations for salivary gland disorders. (author)

  13. Measurement of myocardial perfusion using magnetic resonance

    DEFF Research Database (Denmark)

    Fritz-Hansen, T.; Jensen, L.T.; Larsson, H.B.

    2008-01-01

    Cardiac magnetic resonance imaging (MRI) has evolved rapidly. Recent developments have made non-invasive quantitative myocardial perfusion measurements possible. MRI is particularly attractive due to its high spatial resolution and because it does not involve ionising radiation. This paper reviews...... myocardial perfusion imaging with MR contrast agents: methods, validation and experiences from clinical studies. Unresolved issues still restrict the use of these techniques to research although clinical applications are within reach Udgivelsesdato: 2008/12/8...

  14. Evanescent Waves Nuclear Magnetic Resonance

    DEFF Research Database (Denmark)

    Halidi, El Mohamed; Nativel, Eric; Akel, Mohamad

    2016-01-01

    Nuclear Magnetic Resonance spectroscopy and imaging can be classified as inductive techniques working in the near- to far-field regimes. We investigate an alternative capacitive detection with the use of micrometer sized probes positioned at sub wavelength distances of the sample in order...

  15. Children's (Pediatric) Magnetic Resonance Imaging

    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 Children’s (Pediatric) Magnetic Resonance ...

  16. 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) - ...

  17. Children's (Pediatric) Magnetic Resonance Imaging

    Medline Plus

    Full Text Available ... Magnetic Resonance Imaging 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 ...

  18. 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 ...

  19. Children's (Pediatric) Magnetic Resonance Imaging

    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 ...

  20. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    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 ...

  1. Children's (Pediatric) Magnetic Resonance Imaging

    Medline Plus

    Full Text Available ... of which shows a thin slice of the body. The images can then be studied from different angles by ... about radiology? Share your patient story here Images ... Articles and Media Catheter Angiography Magnetic Resonance, Functional (fMRI) - Brain Children's ( ...

  2. Longitudinal Long-term Magnetic Resonance Imaging and Clinical Follow-up After Single-Row Arthroscopic Rotator Cuff Repair: Clinical Superiority of Structural Tendon Integrity.

    Science.gov (United States)

    Heuberer, Philipp R; Smolen, Daniel; Pauzenberger, Leo; Plachel, Fabian; Salem, Sylvia; Laky, Brenda; Kriegleder, Bernhard; Anderl, Werner

    2017-05-01

    The number of arthroscopic rotator cuff surgeries is consistently increasing. Although generally considered successful, the reported number of retears after rotator cuff repair is substantial. Short-term clinical outcomes are reported to be rarely impaired by tendon retears, whereas to our knowledge, there is no study documenting long-term clinical outcomes and tendon integrity after arthroscopic rotator cuff repair. To investigate longitudinal long-term repair integrity and clinical outcomes after arthroscopic rotator cuff reconstruction. Case series; Level of evidence, 4. Thirty patients who underwent arthroscopic rotator cuff repair with suture anchors for a full-tendon full-thickness tear of the supraspinatus or a partial-tendon full-thickness tear of the infraspinatus were included. Two and 10 years after initial arthroscopic surgery, tendon integrity was analyzed using magnetic resonance imaging (MRI). The University of California, Los Angeles (UCLA) score and Constant score as well as subjective questions regarding satisfaction with the procedure and return to normal activity were used to evaluate short- and long-term outcomes. At the early MRI follow-up, 42% of patients showed a full-thickness rerupture, while 25% had a partial rerupture, and 33% of tendons remained intact. The 10-year MRI follow-up (129 ± 11 months) showed 50% with a total rerupture, while the other half of the tendons were partially reruptured (25%) or intact (25%). The UCLA and Constant scores significantly improved from preoperatively (UCLA total: 50.6% ± 20.2%; Constant total: 44.7 ± 10.5 points) to 2 years (UCLA total: 91.4% ± 16.0% [ P rotator cuff repair showed good clinical long-term results despite a high rate of retears. Nonetheless, intact tendons provided significantly superior clinical long-term outcomes, making the improvement of tendon healing and repair integrity important goals of future research efforts.

  3. Magnetic resonance enterography in pediatric celiac disease.

    Science.gov (United States)

    Koc, Gonca; Doganay, Selim; Sevinc, Eylem; Deniz, Kemal; Chavhan, Govind; Gorkem, Sureyya B; Karacabey, Neslihan; Dogan, Mehmet S; Coskun, Abdulhakim; Aslan, Duran

    To assess if magnetic resonance enterography is capable of showing evidence/extent of disease in pediatric patients with biopsy-proven celiac disease by comparing with a control group, and to correlate the magnetic resonance enterography findings with anti-endomysial antibody level, which is an indicator of gluten-free dietary compliance. Thirty-one pediatric patients (mean age 11.7±3.1 years) with biopsy-proven celiac disease and 40 pediatric patients as a control group were recruited in the study. The magnetic resonance enterography images of both patients with celiac disease and those of the control group were evaluated by two pediatric radiologists in a blinded manner for the mucosal pattern, presence of wall thickening, luminal distention of the small bowel, and extra-intestinal findings. Patient charts were reviewed to note clinical features and laboratory findings. The histopathologic review of the duodenal biopsies was re-conducted. The mean duration of the disease was 5.6±1.8 years (range: 3-7.2 years). In 24 (77%) of the patients, anti-endomysial antibody levels were elevated (mean 119.2±66.6RU/mL). Magnetic resonance enterography revealed normal fold pattern in all the patients. Ten (32%) patients had enlarged mesenteric lymph nodes. Although a majority of the patients had elevated anti-endomysial antibody levels indicating poor dietary compliance, magnetic resonance enterography did not show any mucosal abnormality associated with the inability of magnetic resonance enterography to detect mild/early changes of celiac disease in children. Therefore, it may not be useful for the follow-up of pediatric celiac disease. Copyright © 2017 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

  4. Indications for and clinical procedures resulting from magnetic resonance imaging of the knee in older patients: Are we choosing wisely?

    Science.gov (United States)

    Parent, Marc-Etienne; Vézina, François; Carrier, Nathalie; Masetto, Ariel

    2018-03-01

    To analyze the indications for and clinical procedures resulting from knee magnetic resonance imaging (MRI) in older patients. We retrospectively analyzed 215 medical records of patients 50 years of age and older who had undergone a unilateral knee MRI in 2009. Centre hospitalier universitaire de Sherbrooke in Quebec. Patients 50 years of age and older who underwent a knee MRI in 2009. The main outcome measure was an invasive procedure in the same knee that underwent an MRI. Medical charts were reviewed up to 2014 for patient characteristics, MRI indication, ordering physician specialty, radiography before MRI, MRI findings, and clinical procedures resulting from the MRI. The patients' mean (SD) age was 60.6 (7.5) years. The main MRI indications were meniscopathy (148 [68.8%]) and chronic pain (92 [42.8%]). The main MRI findings were osteoarthritis (OA) (185 [86.0%]) and meniscal lesions (170 [79.1%]). Only 82 (38.1%) patients had a plain radiograph in the 24 months preceding the MRI, usually without a standing anteroposterior view. Findings on pre-MRI radiography (n = 201) demonstrated OA in 144 (71.6%) patients. Overall, 87 (40.5%) patients were seen by an orthopedic surgeon and 27 (31.0%) of these patients underwent an invasive intervention. Among the 81 patients with moderate to severe OA on MRI, 36 (44.4%) had radiographic evidence of moderate to severe OA and only 3 (3.7%) underwent arthroscopic meniscectomy. Our study reproduces the known association between OA and degenerative meniscal changes in older patients. We have found a surprising underuse of the standing anteroposterior view on radiography. Most patients in our cohort could have been appropriately diagnosed and treated based on such radiographic information, as demonstrated by pre-MRI findings, thus avoiding the MRI and subsequent evaluation by an orthopedic surgeon. Meniscectomy was rarely performed, particularly in patients with advanced OA. Educational and pragmatic measures must be emphasized

  5. 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 ...

  6. Advances in magnetic and optical resonance

    CERN Document Server

    Warren, Warren S

    1997-01-01

    Since 1965, Advances in Magnetic and Optical Resonance has provided researchers with timely expositions of fundamental new developments in the theory of, experimentation with, and application of magnetic and optical resonance.

  7. Identification of threshold prostate specific antigen levels to optimize the detection of clinically significant prostate cancer by magnetic resonance imaging/ultrasound fusion guided biopsy.

    Science.gov (United States)

    Shakir, Nabeel A; George, Arvin K; Siddiqui, M Minhaj; Rothwax, Jason T; Rais-Bahrami, Soroush; Stamatakis, Lambros; Su, Daniel; Okoro, Chinonyerem; Raskolnikov, Dima; Walton-Diaz, Annerleim; Simon, Richard; Turkbey, Baris; Choyke, Peter L; Merino, Maria J; Wood, Bradford J; Pinto, Peter A

    2014-12-01

    Prostate specific antigen sensitivity increases with lower threshold values but with a corresponding decrease in specificity. Magnetic resonance imaging/ultrasound targeted biopsy detects prostate cancer more efficiently and of higher grade than standard 12-core transrectal ultrasound biopsy but the optimal population for its use is not well defined. We evaluated the performance of magnetic resonance imaging/ultrasound targeted biopsy vs 12-core biopsy across a prostate specific antigen continuum. We reviewed the records of all patients enrolled in a prospective trial who underwent 12-core transrectal ultrasound and magnetic resonance imaging/ultrasound targeted biopsies from August 2007 through February 2014. Patients were stratified by each of 4 prostate specific antigen cutoffs. The greatest Gleason score using either biopsy method was compared in and across groups as well as across the population prostate specific antigen range. Clinically significant prostate cancer was defined as Gleason 7 (4 + 3) or greater. Univariate and multivariate analyses were performed. A total of 1,003 targeted and 12-core transrectal ultrasound biopsies were performed, of which 564 diagnosed prostate cancer for a 56.2% detection rate. Targeted biopsy led to significantly more upgrading to clinically significant disease compared to 12-core biopsy. This trend increased more with increasing prostate specific antigen, specifically in patients with prostate specific antigen 4 to 10 and greater than 10 ng/ml. Prostate specific antigen 5.2 ng/ml or greater captured 90% of upgrading by targeted biopsy, corresponding to 64% of patients who underwent multiparametric magnetic resonance imaging and subsequent fusion biopsy. Conversely a greater proportion of clinically insignificant disease was detected by 12-core vs targeted biopsy overall. These differences persisted when controlling for potential confounders on multivariate analysis. Prostate cancer upgrading with targeted biopsy increases

  8. Presurgical functional magnetic resonance imaging

    International Nuclear Information System (INIS)

    Stippich, C.

    2010-01-01

    Functional magnetic resonance imaging (fMRI) is an important and novel neuroimaging modality for patients with brain tumors. By non-invasive measurement, localization and lateralization of brain activiation, most importantly of motor and speech function, fMRI facilitates the selection of the most appropriate and sparing treatment and function-preserving surgery. Prerequisites for the diagnostic use of fMRI are the application of dedicated clinical imaging protocols and standardization of the respective imaging procedures. The combination with diffusion tensor imaging (DTI) also enables tracking and visualization of important fiber bundles such as the pyramidal tract and the arcuate fascicle. These multimodal MR data can be implemented in computer systems for functional neuronavigation or radiation treatment. The practicability, accuracy and reliability of presurgical fMRI have been validated by large numbers of published data. However, fMRI cannot be considered as a fully established modality of diagnostic neuroimaging due to the lack of guidelines of the responsible medical associations as well as the lack of medical certification of important hardware and software components. This article reviews the current research in the field and provides practical information relevant for presurgical fMRI. (orig.) [de

  9. Endometrial cancer: magnetic resonance imaging.

    Science.gov (United States)

    Manfredi, R; Gui, B; Maresca, G; Fanfani, F; Bonomo, L

    2005-01-01

    Carcinoma of the endometrium is the most common invasive gynecologic malignancy of the female genital tract. Clinically, patients with endometrial carcinoma present with abnormal uterine bleeding. The role of magnetic resonance imaging (MRI) in endometrial carcinoma is disease staging and treatment planning. MRI has been shown to be the most valuable imaging mod-ality in this task, compared with endovaginal ultrasound and computed tomography, because of its intrinsic contrast resolution and multiplanar capability. MRI protocol includes axial T1-weighted images; axial, sagittal, and coronal T2-weighted images; and dynamic gadolinium-enhanced T1-weighted imaging. MR examination is usually performed in the supine position with a phased array multicoil using a four-coil configuration. Endometrial carcinoma is isointense with the normal endometrium and myometrium on noncontrast T1-weighted images and has a variable appearance on T2-weighted images demonstrating heterogeneous signal intensity. The appearance of noninvasive endometrial carcinoma on MRI is characterized by a normal or thickened endometrium, with an intact junctional zone and a sharp tumor-myometrium interface. Invasive endometrial carcinoma is characterized disruption or irregularity of the junctional zone by intermediate signal intensity mass on T2-weighted images. Invasion of the cervical stroma is diagnosed when the low signal intensity cervical stroma is disrupted by the higher signal intensity endometrial carcinoma. MRI in endometrial carcinoma performs better than other imaging modalities in disease staging and treatment planning. Further, the accuracy and the cost of MRI are equivalent to those of surgical staging.

  10. Endovascular interventional magnetic resonance imaging

    International Nuclear Information System (INIS)

    Bartels, L W; Bakker, C J G

    2003-01-01

    Minimally invasive interventional radiological procedures, such as balloon angioplasty, stent placement or coiling of aneurysms, play an increasingly important role in the treatment of patients suffering from vascular disease. The non-destructive nature of magnetic resonance imaging (MRI), its ability to combine the acquisition of high quality anatomical images and functional information, such as blood flow velocities, perfusion and diffusion, together with its inherent three dimensionality and tomographic imaging capacities, have been advocated as advantages of using the MRI technique for guidance of endovascular radiological interventions. Within this light, endovascular interventional MRI has emerged as an interesting and promising new branch of interventional radiology. In this review article, the authors will give an overview of the most important issues related to this field. In this context, we will focus on the prerequisites for endovascular interventional MRI to come to maturity. In particular, the various approaches for device tracking that were proposed will be discussed and categorized. Furthermore, dedicated MRI systems, safety and compatibility issues and promising applications that could become clinical practice in the future will be discussed. (topical review)

  11. Magnetic resonance imaging and neurolupus

    International Nuclear Information System (INIS)

    Schott, A.M.; Colson, F.; Tebib, J.; Noel, E.; Bouvier, M.

    1990-01-01

    Magnetic resonance imaging (MRI) was assessed in the management of neuropsychiatric manifestations occurring in 6 SLE patients. The MRI scans were normal in 3 cases and was associated with remission of the symptoms except for a patient who experienced a chorea at the time of the examination. Abnormal MRI scans always revealed more lesions than CT scan. 2 different patterns of abnormalities seem to correspond to 2 specific disorders. In 2 patients with clinical presentation suggesting a cortical ischemia by vascular thrombosis, both MRI scans showed areas of abnormal high signal intensities located in the subcortical white matter. In one last patient, MRI scan revealed multiple focal areas of high signal intensities (on T 1 weighter scans) disseminated not only in the deep white matter but also in the gray one. These lesions could be depend upon demyelinisation which may occur by a local vascular process. This serie confirms the interest of MRI in the management of SLE brain involvement as well as it points out some problem of interpretation. This suggest further comparative studies especially at the real onset and during the course of neuro-psychiatric manifestations. At last, the coronal sections may be more informative for the diagnosis and patholophysiology than the horizontal ones [fr

  12. Magnetic resonance for wireless power transfer

    OpenAIRE

    Hui, SYR

    2016-01-01

    Magnetic resonance has been a cornerstone of nonradiative wireless power transfer (WPT) since the late 19th century. However, some researchers have the misconception that magnetic resonance for WPT was developed recently. This article traces some early work of Tesla and other researchers related to the use of magnetic resonance in WPT. Included are some examples of magnetic resonance-based WPT projects conducted by researchers in the biomedical and power electronics communities over the last ...

  13. Contrast-enhanced three-dimensional magnetic resonance angiography of the aorta and its branches. Clinical applications for a new angiographic technique

    International Nuclear Information System (INIS)

    Dolz, J. L.; Vilanova, J. C.; Huguet, M.; Delgado, E.; Baquero, M.; Blanch, A.; Aldoma, J.; Capdevila, A.

    1999-01-01

    Magnetic resonance angiography (MRA) for the study of the aorta has developed at an impressive rate in recent years. It is now possible to evaluate the aorta and its branches by means of magnetic resonance (MR) following administration via peripheral vein of a paramagnetic contrast agent. The approach is similar to that of conventional arteriography, but without the risk associated with iodinated contrast media or invasive arterial catheterization. The technique involves the use of a sequence of ultrafast three-dimensional gradient-echo pulses acquired during apnea. This process enables angiographic or volumetric visualization in the desired plane. The objective of the present report is to describe the technique and demonstrate its many clinical applications. (Author) 23 refs

  14. Multiple systems atrophy: Differentiation and findings by Magnetic resonance

    International Nuclear Information System (INIS)

    Vargas Velez, Sergio Alberto; Alzate Betancur, Catalina Maria

    2006-01-01

    Multiple system atrophy (MSA) is a neuro degenerative disorder of undetermined cause, characterized clinically by Parkinson's, autonomic, cerebellar or pyramidal sing and symptoms. lts differentiation from Parkinson's disease may be difficult, mainly in the early stages owing to overlapping features. Magnetic resonance imaging has demonstrated usefulness in MSA diagnosis and in differentiation with Parkinson's disease. One case with magnetic resonance findings is described

  15. Ultrasonography of the metacarpophalangeal and proximal interphalangeal joints in rheumatoid arthritis: a comparison with magnetic resonance imaging, conventional radiography and clinical examination

    DEFF Research Database (Denmark)

    Szkudlarek, Marcin; Klarlund, Mette; Narvestad, E.

    2006-01-01

    ultrasonography can provide information on signs of inflammation and destruction in RA finger joints that are not available with conventional radiography and clinical examination, and comparable to the information provided by magnetic resonance imaging (MRI). The second to fifth metacarpophalangeal and proximal...... interphalangeal joints of 40 RA patients and 20 control persons were assessed with ultrasonography, clinical examination, radiography and MRI. With MRI as the reference method, the sensitivity, specificity and accuracy of ultrasonography in detecting bone erosions in the finger joints were 0.59, 0.98 and 0...

  16. Magnetic resonance imaging

    International Nuclear Information System (INIS)

    Beer, A.; Bielke, G.; Bockenheimer, S.; Brenner, G.; Dieringer, H.; Esswein, H.; Hopf, H.; Koch, H.; Meves, M.; Nagel, F.; Oberstein, A.; Ostheimer, E.; Pfaff, M.; Schlaps, D.; Schopka, H.J.; Seiderer, M.

    1990-01-01

    The study investigates three points of main interest: (1) The clinical efficacy of MR imaging as a routine method, if possible to be assessed in comparison to comparable imaging methods, and referring to a broad spectrum of available types of equipment and modes of operation, to be expressed in terms of diagnostic value and indication of therapy. (2) Specific economic aspects, considering different sites of operation and application conditions. (3) Results of clinical application with regard to individual cases (patient careers), in order to establish a nationwide basis for economic cost-benefit assessment of this diagnostic tool. Another aspect taken into account whenever available data allow so, is substitutional or additional application of MR imaging. The survey is performed on the basis of data accumulated by more than 21.000 MR examinations, and of data describing the application environment, furnished by 25 users from university hospitals, general hospitals, or private practice. (orig./HP) [de

  17. Magnetic resonance imaging of infectious myositis

    Energy Technology Data Exchange (ETDEWEB)

    Yun, Ji Young; Kim, Jee Young; Kim, Sang Heum; Jung, Youn Ju; Cha, Eun Suk; Park, Joung Mi; Park, Young Ha [The Catholic Univ., College of Medicine, Suwon (Korea, Republic of)

    1998-09-01

    To describe the findings of magnetic resonance imaging in infectious myositis and to determine their value for differentiation between ruberculous and bacterial myositis. Magnetic resonance images of ten proven cases of infectious myositis (five tuberculous and five bacterial) were retrospectively reviewed in the light of clinical and laboratory findings. On the basis of magnetic resonance images, signal intensity of the mass, the presence or absence of an abscess, signal intensity of the peripheral wall, patterns of contrast enhancement, and associated findings were evaluated. Compared with those of bacterial myositis, the symptoms of tuberculous myositis lasted longer but there were no difinite local inflammatory signs. In three of five cases of bacterial myositis there were specific medical records;trauma in two cases and systemic lupus erythematosus in one. All tuberculous myositis cases involved a single muscle, but bacterial myositis affected multipe muscles in three cases(60%). All but one case showed a mass in the involved muscles. In one bacterial case, there was diffuse swelling in the involved muscle. On T1-weighted images, eight infectious cases showed low signal intensity;two, of the bactrerial type, showed subtle increased signal intensity. all cases demonstrated high signal intensity on t2-weighted images. The signal intensity of peripheral wall was slightly increased on T1-weighted images, but low on T2-weighted. In four cases there was associated cellulitis, and in one case each, adjacent joint effusion and deep vein thrombosis were seen. After gadolinium infusion, peripheral rim enhancement was noted in nine cases and heterogeneous enhancement in one. After magnetic resonance imaging of infectious myositis, the characteristic finding was an abscessed lesion, with the peripheral wall showing high signal intensity on T1-weighted images and low signal intensity on T2 weighted. Although we found it difficult to differentiate bacterial from tuberculous

  18. Magnetic resonance imaging of infectious myositis

    International Nuclear Information System (INIS)

    Yun, Ji Young; Kim, Jee Young; Kim, Sang Heum; Jung, Youn Ju; Cha, Eun Suk; Park, Joung Mi; Park, Young Ha

    1998-01-01

    To describe the findings of magnetic resonance imaging in infectious myositis and to determine their value for differentiation between ruberculous and bacterial myositis. Magnetic resonance images of ten proven cases of infectious myositis (five tuberculous and five bacterial) were retrospectively reviewed in the light of clinical and laboratory findings. On the basis of magnetic resonance images, signal intensity of the mass, the presence or absence of an abscess, signal intensity of the peripheral wall, patterns of contrast enhancement, and associated findings were evaluated. Compared with those of bacterial myositis, the symptoms of tuberculous myositis lasted longer but there were no difinite local inflammatory signs. In three of five cases of bacterial myositis there were specific medical records;trauma in two cases and systemic lupus erythematosus in one. All tuberculous myositis cases involved a single muscle, but bacterial myositis affected multipe muscles in three cases(60%). All but one case showed a mass in the involved muscles. In one bacterial case, there was diffuse swelling in the involved muscle. On T1-weighted images, eight infectious cases showed low signal intensity;two, of the bactrerial type, showed subtle increased signal intensity. all cases demonstrated high signal intensity on t2-weighted images. The signal intensity of peripheral wall was slightly increased on T1-weighted images, but low on T2-weighted. In four cases there was associated cellulitis, and in one case each, adjacent joint effusion and deep vein thrombosis were seen. After gadolinium infusion, peripheral rim enhancement was noted in nine cases and heterogeneous enhancement in one. After magnetic resonance imaging of infectious myositis, the characteristic finding was an abscessed lesion, with the peripheral wall showing high signal intensity on T1-weighted images and low signal intensity on T2 weighted. Although we found it difficult to differentiate bacterial from tuberculous

  19. Magnetic resonance: safety measures and biological effects

    International Nuclear Information System (INIS)

    Gordillo, I.; Lafuente, J.; Fernandez, C.; Barbero, M.J.; Cascon, E.

    1997-01-01

    The biological effects of electromagnetic fields is currently a subject of great controversy. For this reason, magnetic resonance imaging (MRI) and spectroscopy are constantly under investigation. The source of the risk in MRI is associated with the three types of electromagnetic radiation to which the patient is exposed: the static magnetic field, variable (gradient) magnetic fields and radiofrequency fields. Each is capable of producing significant biological effects when employed at sufficient intensity. Patients exposed to risk sources are those situated within the lines of force of the magnetic field, ellipsoid lines that are arranged around the magnet, representing the strength of the surrounding field. To date, at the intensity normally utilized in MRI(<2T) and respecting the field limit recommendations established by the US Food and Drug Administration (FDA) for clinical use of this technique no adverse secondary biological effects have been reported. The known biological effects and other possible secondary effects are reviewed, and the recommended safety measures are discussed. (Author)

  20. Large intracranial vessel occlusive vasculopathy after radiation therapy in children: clinical features and usefulness of magnetic resonance imaging

    International Nuclear Information System (INIS)

    Omura, Motoko; Aida, Noriko; Sekido, Kenichi; Kakehi, Masae; Matsubara, Sho

    1997-01-01

    Purpose: To assess the relationship between large intracranial vessel occlusive vasculopathy (vasculopathy) and radiation therapy, and to clarify the clinical efficacy of magnetic resonance (MR) imaging in the diagnosis and screening of the vasculopathy. Methods and Materials: We retrospectively evaluated the medical records and serial MR images for 32 pediatric patients, in whom radiation therapy had been given to fields including the circle of Willis and major cerebral arteries. All children had periodically undergone follow-up neurologic assessment and MR imaging examinations at Kanagawa Children's Medical Center for more than one year after radiation therapy (range 1.3-14 years). Patients who had not remained free of tumor progression up to the time of final evaluation were excluded. Results: Vasculopathy developed in 6 of 32 patients 2-13 years after radiation therapy. Three of them presented with transient ischemic attacks (TIA) and the other three showed infarctions without preceding TIA. Steno-occlusive changes of major cerebral arteries were identified by MR imaging in all six patients, but not obtained in the remaining 26 patients. In the patients with TIA, MR imaging demonstrated steno-occlusive changes at the time of TIA, before irreversible infarction. They have been doing well subsequent to encephaloduraoarteriosyn-angiosis. In the three patients who presented infarction without preceding TIA, MR imaging did not demonstrate the vascular change before the onset of infarction, and two of them developed neurologic deficits. The mean exposure dose for the circle of Willis and major cerebral arteries in these six patients was significantly higher than that in the remaining 26 patients without this sequela (61Gy vs. 50Gy, p < 0.05). The mean age at radiation therapy of the six patients was lower, but the difference was not significant. Conclusion: The incidence of vasculopathy after radiation therapy has a considerable correlation with radiation dose and

  1. Clinical outcome of magnetic-resonance-guided focused ultrasound surgery (MRgFUS) in the treatment of symptomatic uterine fibroids

    International Nuclear Information System (INIS)

    Kamp, J.E.K.; Scheurig-Muenkler, C.; Beck, A.; David, M.; Hengst, S.

    2013-01-01

    Purpose: To investigate the clinical outcome of magnetic-resonance-guided focused ultrasound surgery (MRgFUS) treatment for symptomatic uterine fibroids in premenopausal women using the validated USF-QOL (Uterine Fibroid Symptom and Quality of Life) Questionnaire. Materials and Methods: 54 patients with symptomatic uterine fibroids were enrolled in this prospective study. The patients completed the UFS-QOL Questionnaire prior to MRgFUS treatment as well as after 3, 6, and 12 months. Results: The rate of technical success was 91.5 % (95.2 % after subtraction of screening errors). 6/54 patients (11 %) had other treatments (surgery, n = 4; UAE, n = 2), 8/54 (15 %) dropped out due to pregnancy, and 8/54 were lost to follow-up. The remaining group showed considerable symptom relief as early as after 3 months. The median overall quality of life score increased from 64.7 (quartile range QR: 49.8 - 77.6) before treatment to 77.6 (QR: 61.4 - 87.1) (p < 0.001), 78.4 (QR: 66.4 - 89.7) (p < 0.001), and 82.8 (QR: 69.8 - 92.2) (p < 0.001) at 3, 6, and 12 months, respectively. The corresponding median symptom severity score decreased from 46.9 (QR: 28.1 - 56.2) to 34.4 (QR: 21.9 - 43.7) at 3 months (p = 0.003) and 28.1 at 6 and 12 months (QR: 18.7 - 38.3, QR: 15.6 - 34.4) (p < 0.001, p = 0.002). The rate of complications requiring treatment was 9 %, and the rate of overall complications was 39 %. No major complications occurred. Conclusion: Our results indicate significant alleviation of fibroid-related symptoms within 12 months of MRgFUS with improvement beginning as early as 3 months after treatment. We observed no major complications, and some women became pregnant after MRgFUS. There was a low treatment failure rate of 11 %. (orig.)

  2. Arthroscopic Suture Anchor Fixation of Bony Bankart Lesions: Clinical Outcome, Magnetic Resonance Imaging Results, and Return to Sports.

    Science.gov (United States)

    Plath, Johannes E; Feucht, Matthias J; Bangoj, Robert; Martetschläger, Frank; Wörtler, Klaus; Seppel, Gernot; Aboalata, Mohamed; Tischer, Thomas; Imhoff, Andreas B; Vogt, Stephan

    2015-08-01

    The purpose of this study was to evaluate the outcome, return to sporting activity, and postoperative articular cartilage and bony morphology of shoulders that underwent arthroscopic suture anchor repair of bony Bankart lesions. The inclusion criteria for this retrospective study were anterior glenoid rim fractures after traumatic shoulder instability that were treated with arthroscopic suture anchor repair. Patients were surveyed by a questionnaire including sport-specific outcome, Rowe score, Western Ontario Shoulder Instability Index, and Oxford Instability Score. Three-tesla magnetic resonance imaging could be performed in 30 patients to assess osseous integration, glenoid reconstruction, and signs of osteoarthritis. From November 1999 to April 2010, 81 patients underwent an anterior bony Bankart repair in our department (50 arthroscopic suture anchor repairs, 5 arthroscopic screw fixations, and 26 open repairs). The 55 arthroscopic repairs comprised a consecutive cohort of patients treated by a single surgeon. Of the 50 patients in the suture anchor group, 45 (90%) were available for evaluation. At 82 ± 31 months postoperatively, the mean Rowe score was 85.9 ± 20.5 points, the mean Western Ontario Shoulder Instability Index score was 89.4% ± 14.7%, and the mean Oxford Instability Score was 13.6 ± 5.4 points. Compared with the contralateral shoulder, all scores showed a significantly reduced outcome (P sporting activity after surgery. The number of sports disciplines (P < .001), duration (P = .005), level (P = .02), and risk category (P = .013) showed a significant reduction compared with the pretrauma condition. However, only 19% of patients reported that shoulder complaints were the reason for the reduction in activity. Nonunion occurred in 16.6%, with a higher frequency in patients with chronic lesions (P = .031). Anatomic reduction was achieved in 72%, the medial step-off in patients with nonanatomic reduction averaged 1.8 ± 0.9 mm, and the

  3. [Magnetic resonance guided focused ultrasound surgery for pain palliation of bone metastases: early experience of clinical application in China].

    Science.gov (United States)

    Gu, Jianjun; Wang, Han; Tang, Na; Hua, Yingqi; Yang, Haiyan; Qiu, Yimin; Ge, Renbin; Zhou, Ying; Wang, Wenwen; Zhang, Guixiang

    2015-11-03

    To evaluate the safety and efficacy of magnetic resonance guided focused ultrasound surgery (MRgFUS) in treatment for pain palliation of bone metastases. Eighty-one patients of painful bone metastases were volunteered to screen for this study in Shanghai General Hospital from June 2014 to February 2015. Twenty-three patients among them were treated by MRgFUS, who was more than 18-years old, having the ability to fully understand the informed consent of the research, suffering with pain of numeric rating scale (NRS) ≥ 4, non-received radiotherapy or chemotherapy for pain palliation of bone metastases in the past two weeks. The NRS, the standard question of Brief Pain Inventory (BPI-QoL), and the standard question of Europe Organization for Research and Treatment of Cancer Quality of Life Questionnaire- Bone Metastases 22 (EORTC QLQ-BM22) were respectively recorded before and 1-week, 1-month, 3-month after the treatment. The related adverse events of MRgFUS were observed and recorded in 3 months after the treatment as well. (1)Twenty-three metastatic bone tumor lesions of 23 patients were treated by MRgFUS, the treatment data was as follows: the mean treatment time was (88 ± 33) minutes, the mean sonication number was 13 ± 8. (2) Adverse events included: pain in therapy area 3/23, which spontaneous relieving within one week; numbness in lower limb (1/23), which relieved after physiotherapy. (3) The NRS of before treatment and at 1-week, 1-month, and 3-month after treatment respectively was 6.0 ± 1.5, 3.7 ± 1.7,3.1 ± 2.0, and 2.2 ± 1.0,which significantly decreased after the treatment (P<0.01). (4) The BPI-QoL score of before treatment and at 1-week, 1-month, and 3-month after treatment respectively was 39 ± 16, 27 ± 18, 26 ± 18, and 21 ± 18, which significantly decreased after the treatment (P<0.01). (5) The EORTC QLQ-BM22 score of before treatment and at 1-week, 1-month, and 3-month after treatment respectively was 52 ± 13, 44 ± 12, 42 ± 12, and 39

  4. Interventional magnetic resonance imaging

    International Nuclear Information System (INIS)

    Debatin, J.F.; Adam, G.

    1998-01-01

    With the advent of open configuration MR imaging systems, the vision of MRI-based guidance, control, and monitoring of minimally invasive interventions has evolved from a hypothetical concept to a practical possibility. This book provides a comprehensive overview of the very exciting emerging field of interventional MRI. The international authorship provides firsthand experience of all relevant topics. This book will familiarize the reader with the basic principles underlying currently available hardware and software configurations. In addition, technical aspects of thermosensitive imaging, techniques for instrument visualization, and safety aspects are covered. Finally, the book emphasizes both existing and future clinical applications. (orig.)

  5. Clinical study of intermittent lock of the temporomandibular joint. Relation to frequency of intermittent lock on clinical examination and magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Ide, Takashi; Nagai, Itaru; Miyazaki, Akihiro; Yamaguchi, Akira; Kohama, Geniku [Sapporo Medical Univ. (Japan). School of Medicine

    2002-03-01

    To examine the occurrence of intermittent lock, we investigated the correlation between the frequency of intermittent lock of the temporomandibular joint and magnetic resonance imaging (MRI) findings. The subjects consisted of 25 patients (25 joints) with unilateral intermittent lock who were treated from April 1994 through March 2000 at our department. MRI examination of the joint was performed on the affected side. We divided the patients into two groups: a high-frequency group consisting of 15 patients who had symptoms of intermittent lock every day and a low-frequency group consisting of 10 patients who did not have symptoms every day. The results showed no statistical difference between the two groups in clinical findings such as age, sex, clicking side of the joint, duration of intermittent lock, method of unlocking, muscle pain on palpation, degree of maximal mouth opening, distance between the maxillary and mandibular tooth midline, or the degree of overbite and overjet. However, the two groups differed significantly in the degree of anterior disc displacement as assessed by MRI. (author)

  6. Magnetic resonance and its applications

    CERN Document Server

    Chizhik, Vladimir I; Donets, Alexey V; Frolov, Vyacheslav V; Komolkin, Andrei V; Shelyapina, Marina G

    2014-01-01

    The book provides a basic understanding of the underlying theory, fundamentals and applications of magnetic resonance The book implies a few levels of the consideration (from simple to complex) of phenomena, that can be useful for different groups of readers The introductory chapter provides the necessary underpinning knowledge for newcomers to the methods The exposition of theoretical materials goes from initial to final formulas through detailed intermediate expressions.

  7. Magnetic resonance in multiple sclerose twins

    International Nuclear Information System (INIS)

    Polman, C.H.; UitdeHaag, B.M.J.; Koetsier, C.J.; Valk, J.; Lucas, C.J.

    1989-01-01

    Magnetic resonance imaging (MR) examinations were performed in a series of 7 twin sets (4 monozygotic and 3 dizygotic) and one triplet set who were clinically discordant for multiple sclerosis (MS). MRI abnormalities were detected in a number of the unaffected members of the nonzygotic twin pairs. The authors discuss the possible implications of their findings for the present view on the aetiology of MS. (author). 3 refs.; 1 fig.; 1 tab

  8. Basic principles of nuclear magnetic resonance imaging

    International Nuclear Information System (INIS)

    Valk, J.; MacLean, C.; Algra, P.R.

    1985-01-01

    The intent of this book is to help clinicians understand the basic physical principles of magnetic resonance (MR) imaging. The book consists of the following: a discussion of elementary considerations; pulse sequencing; localization of MR signals in space; MR equipment; MR contrast agents; clinical applications; MR spectroscopy; and biological effects of MR imaging; a set of appendixes; and a bibliography. Illustrations and images are included

  9. Magnetic resonance imaging in MELAS syndrome

    International Nuclear Information System (INIS)

    Rosen, L.; Phillips, S.; Enzmann, D.

    1990-01-01

    MELAS syndrome is a distinct clinical entity belonging to a group of mitochondrial encephalomyopathies characterized by the tetrad of myopathy, encephalopathy, lactic acidosis, and stroke-like episodes. Computed tomography (CT) and magnetic resonance (MR) findings are reviewed in a patient with MELAS. Serial CT studies demonstrated multiple 'migrating' infarcts in various stages of evolution involving primarily the posterior temporal and occipital regions. MR was more sensitive than CT in demonstrating the number and extent of cortical lesions in this disease entity. (orig.)

  10. Magnetic resonance imaging findings as predictors of clinical outcome in patients with sciatica receiving active conservative treatment

    DEFF Research Database (Denmark)

    Jensen, Tue Secher; Albert, Hanne B; Sorensen, Joan S

    2007-01-01

    OBJECTIVE: The aims of this study were to investigate the possible prognostic value of disk-related magnetic resonance imaging (MRI) findings in relation to recovery at 14 months in patients with severe sciatica, and whether improvement of disk herniation and/or nerve root compromise is concurrent...... with recovery. METHODS: All patients included in this prospective observational study of patients with sciatica receiving active conservative treatment were scanned at baseline and at 14 months' follow-up. Definite recovery at follow-up was defined as an absence of sciatic leg pain and a Roland Morris...... in that the prevalence of disk-related MRI findings was different for men and women, and they had different recovery rates. Improvement of disk herniations and nerve root compromise over time did not coincide with definite recovery. CONCLUSIONS: In patients with sciatica receiving active conservative treatment, broad...

  11. A hyperpolarized equilibrium for magnetic resonance.

    Science.gov (United States)

    Hövener, Jan-Bernd; Schwaderlapp, Niels; Lickert, Thomas; Duckett, Simon B; Mewis, Ryan E; Highton, Louise A R; Kenny, Stephen M; Green, Gary G R; Leibfritz, Dieter; Korvink, Jan G; Hennig, Jürgen; von Elverfeldt, Dominik

    2013-01-01

    Nuclear magnetic resonance spectroscopy and imaging (MRI) play an indispensable role in science and healthcare but use only a tiny fraction of their potential. No more than ≈10 p.p.m. of all ¹H nuclei are effectively detected in a 3-Tesla clinical MRI system. Thus, a vast array of new applications lays dormant, awaiting improved sensitivity. Here we demonstrate the continuous polarization of small molecules in solution to a level that cannot be achieved in a viable magnet. The magnetization does not decay and is effectively reinitialized within seconds after being measured. This effect depends on the long-lived, entangled spin-order of parahydrogen and an exchange reaction in a low magnetic field of 10⁻³ Tesla. We demonstrate the potential of this method by fast MRI and envision the catalysis of new applications such as cancer screening or indeed low-field MRI for routine use and remote application.

  12. Characteristic cardiac phenotypes are detected by cardiovascular magnetic resonance in patients with different clinical phenotypes and genotypes of mitochondrial myopathy.

    Science.gov (United States)

    Florian, Anca; Ludwig, Anna; Stubbe-Dräger, Bianca; Boentert, Matthias; Young, Peter; Waltenberger, Johannes; Rösch, Sabine; Sechtem, Udo; Yilmaz, Ali

    2015-05-22

    Mitochondrial myopathies (MM) are a heterogeneous group of inherited conditions resulting from a primary defect in the mitochondrial respiratory chain with consecutively impaired cellular energy metabolism. Small sized studies using mainly electrocardiography (ECG) and echocardiography have revealed cardiac abnormalities ranging from conduction abnormalities and arrhythmias to hypertrophic or dilated cardiomyopathy in these patients. Recently, characteristic patterns of cardiac involvement were documented by cardiovascular magnetic resonance (CMR) in patients with chronic progressive external ophthalmoplegia (CPEO)/Kearns-Sayre syndrome (KSS) and with mitochondrial encephalopathy with lactic acidosis and stroke-like episodes (MELAS). The present study aimed to characterize the prevalence and pattern of cardiac abnormalities and to test the additional diagnostic value of CMR in this patient population. The hypothesis that different neuromuscular MM syndromes present with different cardiac disease phenotypes was evaluated. Sixty-four MM patients (50 ± 15 years, 44% male) and 25 matched controls (52 ± 14 years, 36% male) prospectively underwent cardiac evaluations including CMR (comprising cine- and late-gadolinium-enhancement (LGE) imaging). Based on the neuromuscular phenotype and genotype, the patients were grouped: (a) CPEO/KSS (N = 33); (b) MELAS/-like (N = 11); c) myoclonic epilepsy with ragged-red fibers (MERRF) (N = 3) and d) other non-specific MM forms (N = 17). Among the 64 MM patients, 34 (53%) had at least one abnormal CMR finding: 18 (28%) demonstrated an impaired left ventricular ejection-fraction (LV-EF patients showed significantly higher maximal wall thickness (10 ± 3 vs. 8 ± 2 mm, p = 0.005) and concentricity (LV mass to end-diastolic volume: 0.84 ± 0.27 vs. 0.67 ± 0.11, p patients showed the highest frequency of cardiac disease (in 10/11 (91%)), a mostly concentric LV hypertrophy (6/9; 67%) with or

  13. Contemporary imaging: Magnetic resonance imaging, computed tomography, and interventional radiology

    International Nuclear Information System (INIS)

    Goldberg, H.I.; Higgins, C.; Ring, E.J.

    1985-01-01

    In addition to discussing the most recent advances in magnetic resonance imaging (MRI), computerized tomography (CT), and the vast array of interventional procedures, this book explores the appropriate clinical applications of each of these important modalities

  14. Artifacts Affecting Musculoskeletal Magnetic Resonance Imaging: Their Origins and Solutions.

    Science.gov (United States)

    Roth, Eira; Hoff, Michael; Richardson, Michael L; Ha, Alice S; Porrino, Jack

    2016-01-01

    Among articles within the radiology literature, few present the manifestations of magnetic resonance imaging artifacts in a clinically oriented manner. Recognizing such artifacts is imperative given the increasing clinical use of magnetic resonance imaging and the emphasis by the American Board of Radiology on practical physics applications. The purpose of this article is to present magnetic resonance physics principles visually and conceptually in the context of common musculoskeletal radiology artifacts and their solutions, described using nonmathematical explanations. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Magnetic resonance imaging and morphometric histologic analysis of prostate tissue composition in predicting the clinical outcome of terazosin therapy in benign prostatic hyperplasia

    Energy Technology Data Exchange (ETDEWEB)

    Isen, K. [Karaelmas Univ., Zonguldak (Turkey). School of Medicine; Sinik, Z.; Alkibay, T.; Sezer, C.; Soezen, S.; Atilla, S.; Ataoglu, O.; Isik, S.

    2001-02-01

    The purpose of this study was to determine whether magnetic resonance imaging (MRI) or quantitative color-imaged morphometric analysis (MA) of the prostate gland are related to the clinical response to terazosin. Thirty-six male patients with symptomatic benign prostatic hyperplasia (BPH) with a serum prostate-specific antigen level of 4-10 ng/mL underwent MRI with body coil, transrectal prostate unltrasonography and biopsy prior to terazosin therapy. For MRI-determined stromal and non-stromal BPH, the ratio of the signal intensity of the inner gland to the obturator internus muscle was evaluated. Histologic sections were stained with hematoxylin and eosin. The MA of the specimens was performed by Samba 2000. Results of the two techniques were interpreted according to the terazosin therapy results. The mean stromal percentage was 60.5{+-}18.0%. No statistically significant relationship was found between the clinical outcome of terazosin and the MRI findings. The MA results showed a significant relationship between the percentage of stroma and the percent change of the peak urinary flow rate, but not with the percent change of the international prostate symptom score after terazosin therapy (P<0.05). Magnetic resonance imaging alone is not sufficient in predicting the response to terazosin therapy. Morphometric analysis of BPH tissue composition can be used in predicting the clinical outcome of terazosin therapy but it is suitable only in patients for whom prostatic biopsy is necessary in order to rule out prostate cancer. (author)

  16. Magnetic resonance imaging and morphometric histologic analysis of prostate tissue composition in predicting the clinical outcome of terazosin therapy in benign prostatic hyperplasia

    International Nuclear Information System (INIS)

    Isen, K.; Sinik, Z.; Alkibay, T.; Sezer, C.; Soezen, S.; Atilla, S.; Ataoglu, O.; Isik, S.

    2001-01-01

    The purpose of this study was to determine whether magnetic resonance imaging (MRI) or quantitative color-imaged morphometric analysis (MA) of the prostate gland are related to the clinical response to terazosin. Thirty-six male patients with symptomatic benign prostatic hyperplasia (BPH) with a serum prostate-specific antigen level of 4-10 ng/mL underwent MRI with body coil, transrectal prostate unltrasonography and biopsy prior to terazosin therapy. For MRI-determined stromal and non-stromal BPH, the ratio of the signal intensity of the inner gland to the obturator internus muscle was evaluated. Histologic sections were stained with hematoxylin and eosin. The MA of the specimens was performed by Samba 2000. Results of the two techniques were interpreted according to the terazosin therapy results. The mean stromal percentage was 60.5±18.0%. No statistically significant relationship was found between the clinical outcome of terazosin and the MRI findings. The MA results showed a significant relationship between the percentage of stroma and the percent change of the peak urinary flow rate, but not with the percent change of the international prostate symptom score after terazosin therapy (P<0.05). Magnetic resonance imaging alone is not sufficient in predicting the response to terazosin therapy. Morphometric analysis of BPH tissue composition can be used in predicting the clinical outcome of terazosin therapy but it is suitable only in patients for whom prostatic biopsy is necessary in order to rule out prostate cancer. (author)

  17. CLINICAL APPLICABILITY OF HUMAN IN-VIVO LOCALIZED P-31 MAGNETIC-RESONANCE SPECTROSCOPY OF BONE AND SOFT-TISSUE TUMORS

    NARCIS (Netherlands)

    HOEKSTRA, HJ; BOEVE, WJ; KAMMAN, RL; MOOYAART, EL

    1994-01-01

    Background: Magnetic resonance imaging (MRI) is of restricted value for the in vivo characterization of tumor types. The applicability of phosphorus-31 (P-31) magnetic resonance spectroscopy (MRS) in the diagnosis of bone and soft tissue tumors is unknown. Methods: A total of 191 consecutive

  18. Magnetic resonance imaging of the cardiovascular system

    International Nuclear Information System (INIS)

    Masuda, Yoshiaki; Imai, Hiroshi; Watanabe, Sigeru; Inagaki, Yoshiaki; Tateno, Yukio; Ikehira, Hiroo.

    1990-01-01

    Magnetic resonance imaging (MRI) is a new noninvasive technique for visualization of the cardiovascular system, and is used to evaluate tissue characteristics, cardiac function and blood flow abnormalities, as well as to obtain morphological information. In this paper we presented results of clinical and laboratory research obtained using conventional spin echo MRI with regard to cardiovascular anatomy, tissue characterization and physiology. Furthermore, experience with two new techniques, cine-MRI and volume-selected MR spectroscopy, and their potential clinical usefulness in detecting cardiovascular diseases are documented. (author)

  19. Cerebral fat embolism: magnetic resonance study

    International Nuclear Information System (INIS)

    Guedea, A.; Barrena, R.; Guelbenzu, S.; Tejada, A.

    1998-01-01

    We report the case of 26-year-old man who presented clinical evidence of fat embolism following a traffic accident. Although computed tomography (CT) of the brain showed no abnormalities, magnetic resonance imaging (MRI) disclosed several scattered points of high intensity on T2-weighted and proton density (PD) images, with complete resolution of the lesions on follow-up scan. MRI is considered more sensitive than computed tomography in detecting these lesions, and may be useful for their diagnosis, correlating well with the clinical course. (Author) 10 refs

  20. The nuclear magnetic resonance well logging

    International Nuclear Information System (INIS)

    Zhang Yumin; Shen Huitang

    2003-01-01

    In this paper, the characteristic of the nuclear magnetic resonance logging is described at first. Then its development and its principle is presented. Compared with the nuclear magnetic resonance spectrometer, the magnet techniques is the first question that we must solve in the manufacture of the NMR well logging

  1. Shimadzu magnetic resonance imaging system, SMT-50

    International Nuclear Information System (INIS)

    Oikawa, Shiro; Nishida, Takayuki; Fujio, Yasuo

    1986-01-01

    The magnetic resonance imaging (MRI) system, as a new modality of medical imaging, has already been put to practical applications on many clinical sites, through which a lot of clinical data has been accumulated. It can offer a powerful new probe of internal anatomy of the human body and its functions. Now that the MRI has established its effectiveness in diagnosis, a really practical MRI system which features high efficiency and economical design with high patient throughput is strongly called for. Introduced in this article is a superconductive magnet MRI system, SMT-50, operating at 5000 Gauss. It has realized an excellent diagnostic capability with such functions as multi-slice multi-echo imaging, high sensitive, surface coil technique and so on. High resolution image display (1024 x 1024 pixcel) unit and separate console system (viewing console and scanning console) will assist high patient throughput. The outline of the SMT-50 and its clinical data are reported here. (author)

  2. Magnetic resonance imaging at Rikshospitalet

    International Nuclear Information System (INIS)

    Smith, H.J.

    1990-01-01

    During the first 18 months of operations of the nuclear magnetic resonance (NMR) unit at Rikshospitalet, 1453 NMR examinations have been performed on 1431 patients. 64% of the time has been devoted to examinations of the central nervous system and spine in children and adults, 9% of the time has been used on non-neuroradiology pediatric patients, while the rest of the time has been spent equally on ear, nose and throat, thoracic (including cardiac) and abdominal examinations in adult patients. The indications for doing NMR at Rikshospitalet are listed and discussed, and it is concluded that NMR has proved to be useful at several conditions in most organ systems. 15 refs

  3. Magnetic resonance imaging in psychiatry

    International Nuclear Information System (INIS)

    Mann, K.

    1993-01-01

    Diagnosis and research in psychiatry are increasingly availing themselves of magnetic resonance imaging (MRI). In comparison to computed tomography (CT), this offers the combined benefits of no exposure to radiation, high resolution, artefact-free display of structures near bone, and a sharp contrast between the grey and white brain matter, with freedom to select the section. With the exception of very anxious patients, MRI will gradually replace CT scans for a wide range of differential diagnostic investigations. Its superiority in systematic studies of psychiatric patients with discrete cerebral parenchyma lesions is already considered proven. This is illustrated on the basis of research into schizophrenia and alcoholism. (orig.) [de

  4. Advances in magnetic resonance 3

    CERN Document Server

    Waugh, John S

    2013-01-01

    Advances in Magnetic Resonance, Volume 3, describes a number of important developments which are finding increasing application by chemists. The book contains five chapters and begins with a discussion of how the properties of random molecular rotations reflect themselves in NMR and how they show up, often differently, in other kinds of experiments. This is followed by separate chapters on the Kubo method, showing its equivalence to the Redfield approach in the cases of most general interest; the current state of dynamic nuclear polarization measurements in solutions and what they tell us abou

  5. PET measurements of myocardial blood flow post myocardial infarction: Relationship to invasive and cardiac magnetic resonance studies and potential clinical applications.

    Science.gov (United States)

    Gewirtz, Henry

    2017-12-01

    This review focuses on clinical studies concerning assessment of coronary microvascular and conduit vessel function primarily in the context of acute and sub acute myocardial infarction (MI). The ability of quantitative PET measurements of myocardial blood flow (MBF) to delineate underlying pathophysiology and assist in clinical decision making in this setting is discussed. Likewise, considered are physiological metrics fractional flow reserve, coronary flow reserve, index of microvascular resistance (FFR, CFR, IMR) obtained from invasive studies performed in the cardiac catheterization laboratory, typically at the time of PCI for MI. The role both of invasive studies and cardiac magnetic resonance (CMR) imaging in assessing microvascular function, a key determinant of prognosis, is reviewed. The interface between quantitative PET MBF measurements and underlying pathophysiology, as demonstrated both by invasive and CMR methodology, is discussed in the context of optimal interpretation of the quantitative PET MBF exam and its potential clinical applications.

  6. Resonant and nonresonant magnetic scattering (invited)

    International Nuclear Information System (INIS)

    McWhan, D.B.; Hastings, J.B.; Kao, C.; Siddons, D.P.

    1992-01-01

    The tunability and the polarization of synchrotron radiation open up new possibilities for the study of magnetism. Studies on magnetic materials performed at the National Synchrotron Light Source are reviewed, and they fall into four areas: structure, evolution of magnetic order, separation of L and S, and resonance effects. In the vicinity of atomic absorption edges, the Faraday effect, magnetic circular dichroism, and resonant magnetic scattering are all related resonance effects which measure the spin-polarized density of states. The production and analysis of polarized beams are discussed in the context of the study of magnetism with synchrotron radiation

  7. A simple solution for reducing artefacts due to conductive and dielectric effects in clinical magnetic resonance imaging at 3 T

    International Nuclear Information System (INIS)

    Sreenivas, M.; Lowry, M.; Gibbs, P.; Pickles, M.; Turnbull, L.W.

    2007-01-01

    The quality of imaging obtained at high magnetic field strengths can be degraded by various artefacts due to conductive and dielectric effects, which leads to loss of signal. Various methods have been described and used to improve the quality of the image affected by such artefacts. In this article, we describe the construction and use of a simple solution that can be used to diminish artefacts due to conductive and dielectric effects in clinical imaging at 3 T field strength and thereby improve the diagnostic quality of the images obtained

  8. A simple solution for reducing artefacts due to conductive and dielectric effects in clinical magnetic resonance imaging at 3 T

    Energy Technology Data Exchange (ETDEWEB)

    Sreenivas, M. [Department of Radiology (Yorkshire Deanery-East), Hull Royal Infirmary, Anlaby Road, Hull HU3 2JZ (United Kingdom)]. E-mail: aprilsreenivas@hotmail.com; Lowry, M. [Centre for Magnetic Resonance Investigations, University of Hull, Hull Royal Infirmary, Anlaby Road, 1PR, Hull HU3 2JZ (United Kingdom); Gibbs, P. [Centre for Magnetic Resonance Investigations, University of Hull, Hull Royal Infirmary, Anlaby Road, 1PR, Hull HU3 2JZ (United Kingdom); Pickles, M. [Centre for Magnetic Resonance Investigations, University of Hull, Hull Royal Infirmary, Anlaby Road, 1PR, Hull HU3 2JZ (United Kingdom); Turnbull, L.W. [Centre for Magnetic Resonance Investigations, University of Hull, Hull Royal Infirmary, Anlaby Road, 1PR, Hull HU3 2JZ (United Kingdom)

    2007-04-15

    The quality of imaging obtained at high magnetic field strengths can be degraded by various artefacts due to conductive and dielectric effects, which leads to loss of signal. Various methods have been described and used to improve the quality of the image affected by such artefacts. In this article, we describe the construction and use of a simple solution that can be used to diminish artefacts due to conductive and dielectric effects in clinical imaging at 3 T field strength and thereby improve the diagnostic quality of the images obtained.

  9. Nuclear magnetic resonance (NMR) tomography

    International Nuclear Information System (INIS)

    Skalpe, I.O.

    1984-01-01

    A brief survey of the working principle of the NMR technique in diagnostical medicine is given. Its clinical usefulness for locating tumors, diagnosing various other diseases, such as some mental illnesses and multiple sclerosis, and its possibilities for studying biochemical processes in vivo are mentioned. The price of NMR image scanners and the problems of the strong magnetic field around the machines are mentioned

  10. Tunable Magnetic Resonance in Microwave Spintronics Devices

    Science.gov (United States)

    Chen, Yunpeng; Fan, Xin; Xie, Yunsong; Zhou, Yang; Wang, Tao; Wilson, Jeffrey D.; Simons, Rainee N.; Chui, Sui-Tat; Xiao, John Q.

    2015-01-01

    Magnetic resonance is one of the key properties of magnetic materials for the application of microwave spintronics devices. The conventional method for tuning magnetic resonance is to use an electromagnet, which provides very limited tuning range. Hence, the quest for enhancing the magnetic resonance tuning range without using an electromagnet has attracted tremendous attention. In this paper, we exploit the huge exchange coupling field between magnetic interlayers, which is on the order of 4000 Oe and also the high frequency modes of coupled oscillators to enhance the tuning range. Furthermore, we demonstrate a new scheme to control the magnetic resonance frequency. Moreover, we report a shift in the magnetic resonance frequency as high as 20 GHz in CoFe based tunable microwave spintronics devices, which is 10X higher than conventional methods.

  11. A superconducting magnet for whole-body magnetic-resonance imaging

    International Nuclear Information System (INIS)

    Kan, Hisao; Watanabe, Tsugio; Takechi, Moriaki; Ogino, Osamu; Yamada, Tadatoshi

    1986-01-01

    Magnetic-resonance imaging is a promising new clinical diagnosis system that employs magnetic resonance to generate cross-sectional images of the object under examination. A large magnet plays a critical role in this system-it must supply a high-strength magnetic field that meets rigid standards of space and time uniformity. Mitsubishi Electric has developed a superconducting magnet that not only offers excellent magnetic characteristics but also features reduced helium consumption and a horizontal service port, and permits direct mounting of a magnetic shield. (author)

  12. Magnetic resonance imaging of Parkinsonism

    International Nuclear Information System (INIS)

    Mukai, Eiichiro; Makino, Naoki; Fujishiro, Kenichiro.

    1989-01-01

    We have analyzed magnetic resonance images in 33 patients; 18 patients with Parkinson's disease, 1 patient with diurnally fluctuating progressive dystonia, 1 patient with pure akinesia, 6 patients with multiple system atrophy, 1 patient with flunarizine induced parkinsonism, and 4 patients with unclassified parkinsonism. The MR images were obtained using a 1.5-T GE MR System. A spin-echo pulse sequence was used with a TE of 30 msec and 80 msec and a TR of 2000 msec. No signal abnormalities were seen in any patient with Parkinson's disease but 3 showed slightly decreased signal intensity of the putamen on T2-weighted sequences. Patients with diurnally fluctuating progressive dystonia and pure akinesia evidensed no abnormal findings. All six patients with multiple system atrophy demonstrated decreased signal intensity of the putamen, particularly along their lateral and posterior portions, and an enlarged substantia nigra. Atrophy of the pons and cerebellum was detected in all cases with multiple system atrophy. One case of flunarizine induced parkinsonism showed slightly decreased signal intensity of the putamen. Four cases of unclassified parkinsonism showed decreased signal in the putamen on T2-weighted sequences. Magnetic resonance imaging has the potential to become a useful diagnostic tool in the management of parkinsonism. (author)

  13. Magnetic resonance imaging of Parkinsonism

    Energy Technology Data Exchange (ETDEWEB)

    Mukai, Eiichiro [National Hospital of Nagoya (Japan); Makino, Naoki; Fujishiro, Kenichiro

    1989-06-01

    We have analyzed magnetic resonance images in 33 patients; 18 patients with Parkinson's disease, 1 patient with diurnally fluctuating progressive dystonia, 1 patient with pure akinesia, 6 patients with multiple system atrophy, 1 patient with flunarizine induced parkinsonism, and 4 patients with unclassified parkinsonism. The MR images were obtained using a 1.5-T GE MR System. A spin-echo pulse sequence was used with a TE of 30 msec and 80 msec and a TR of 2000 msec. No signal abnormalities were seen in any patient with Parkinson's disease but 3 showed slightly decreased signal intensity of the putamen on T2-weighted sequences. Patients with diurnally fluctuating progressive dystonia and pure akinesia evidensed no abnormal findings. All six patients with multiple system atrophy demonstrated decreased signal intensity of the putamen, particularly along their lateral and posterior portions, and an enlarged substantia nigra. Atrophy of the pons and cerebellum was detected in all cases with multiple system atrophy. One case of flunarizine induced parkinsonism showed slightly decreased signal intensity of the putamen. Four cases of unclassified parkinsonism showed decreased signal in the putamen on T2-weighted sequences. Magnetic resonance imaging has the potential to become a useful diagnostic tool in the management of parkinsonism. (author).

  14. Migraine and magnetic resonance spectroscopy

    DEFF Research Database (Denmark)

    Younis, Samaira; Hougaard, Anders; Vestergaard, Mark B.

    2017-01-01

    Purpose of review: To present an updated and streamlined overview of the metabolic and biochemical aspect of the migraine pathophysiology based on findings from phosphorous (31P) and hydrogen (1H) magnetic resonance spectroscopy (MRS) studies. Recent findings: Despite of the variation in the meth......Purpose of review: To present an updated and streamlined overview of the metabolic and biochemical aspect of the migraine pathophysiology based on findings from phosphorous (31P) and hydrogen (1H) magnetic resonance spectroscopy (MRS) studies. Recent findings: Despite of the variation...... in the methodology and quality of the MRS migraine studies over time, some results were consistent and reproducible. 31P-MRS studies suggested reduced availability of neuronal energy and implied a mitochondrial dysfunction in the migraine brain. 1H-MRS studies reported interictal abnormalities in the excitatory...... and inhibitory neurotransmitters, glutamate and g-aminobutyric acid (GABA), suggesting persistent altered excitability in migraine patients. N-Acetylaspartate levels were decreased in migraine, probably due to a mitochondrial dysfunction and abnormal energy metabolism. The reported abnormalities may increase...

  15. Clinical significance of bone bruises and cartilage lesions associated with anterior cruciate ligament injuries by magnetic resonance imaging and arthroscopy

    International Nuclear Information System (INIS)

    Nawata, Koji; Yamamoto, Kichizo; Teshima, Ryota; Suzuki, Toshiro; Yamagata, Taiji.

    1995-01-01

    In 85 patients with anterior cruciate ligament (ACL) rupture, we examined bone bruises retrospectively using magnetic resonance imaging (MRI). In 53 patients who underwent arthroscopy, the bone bruises were compared with the cartilage lesions. Depending on the time from their ligamentous injury to the performance of MRI, the patients were divided into three groups: the acute group (less than 1 months, n=29), the subacute group (between 1 and 12 months, n=29), and the chronic group (12 months or more, n=27). The detection rate of bone bruises by MRI was significantly higher in the acute group than in the other groups (p<0.0001). Bone bruises were always detected in the same locations of the lateral compartment of the knee joint. In four patients who observed bone bruises in the first MRI and underwent follow-up MRI 3-6 months later, bone bruises had disappeared in the follow-up MRI. In the acute group, bone bruises in the lateral femoral condyle were often found to be accompanied by cartilaginous injuries. In the subacute and chronic groups, the rate of degeneration of these cartilaginous lesions had progressed. (author)

  16. [Magnetic resonance semiotics of prostate cancer according to the PI-RADS classification. The clinical diagnostic algorithm of a study].

    Science.gov (United States)

    Korobkin, A S; Shariya, M A; Chaban, A S; Voskanvan, G A; Vinarov, A Z

    2015-01-01

    to elaborate the magnetic resonance imaging (MRI) signs of prostate cancer (PC) in accordance with the PI-RADS classification during multiparametric MRI (mpMRI). A total of 89 men aged 20 to 82 years were examined. A control group consisted of 8 (9%) healthy volunteers younger than 30 years of age with no urological history to obtain control images and MRI plots and 20 (22.5%) men aged 26-76 years, whose morphological changes were inflammatory and hyperplastic. The second age-matched group included 61 (68.5%) patients diagnosed with prostate cancer at morphological examination. A set of studies included digital rectal examination, serum prostate-specific antigen, and transrectal ultrasound-guided prostate biopsy. All the patients underwent prostate mpMRI applying a 3.0 T Achieva MRI scanner (Philips, the Netherlands). The patients have been found to have mpMRI signs that were typical of PC; its MRI semiotics according to the PI-RADS classification is presented. Each mpMRI procedure has been determined to be of importance and informative value in detecting PC. The comprehensive mpMRI approach to diagnosing PC improves the quality and diagnostic value of prostate MRI.

  17. Clinical features of congenital cystic disease of the mediastinum. Diagnostic usefulness of computed tomography and magnetic resonance imaging

    International Nuclear Information System (INIS)

    Bando, Masashi; Ishii, Yoshiki; Sugiyama, Yukihiko; Furuse, Makoto; Murayama, Fumio; Sohara, Yasunori

    2000-01-01

    We describe 18 cases of congenital mediastinal cysts, including 4 bronchogenic cysts, 5 pericardial cysts, and 9 thymic cysts. Fifteen of the 18 patients (62.5%) were asymptomatic, and the cysts were found incidentally on a chest radiograph conducted as a part of a physical screening. In 2 of the 4 cases of bronchogenic cysts, the cystic lesions were located in the posterior mediastinum and in the cephalad recess of the azgos vein (CRAzV). In 3 of the 5 cases of pericardial cysts, the lesions were located in the right cardio-phrenic region. In the remaining 2 cases, the cysts were located in the CRAzV and in the posterior mediastinum. Seventeen patients who had histologically proven mediastinal cysts were investigated by magnetic resonance (MR) imaging. In all 3 cases of bronchogenic cysts, MR signals of the cysts were of higher intensity than those of muscle on T1-weighted images. Neither the pericardial cysts nor the thymic cysts showed high signal intensity on T1-weighted images. Macroscopically, the intracystic fluids in all of the bronchogenic cysts contained viscid mucus that probably caused high signal intensities on the T1-weighted images. MR imaging is not only useful in revealing the location of mediastinal cysts, but also in the differential diagnosis of congenital mediastinal cysts. (author)

  18. Advances in mechanical detection of magnetic resonance

    International Nuclear Information System (INIS)

    Kuehn, Seppe; Hickman, Steven A.; Marohn, John A.

    2008-01-01

    The invention and initial demonstration of magnetic resonance force microscopy (MRFM) in the early 1990s launched a renaissance of mechanical approaches to detecting magnetic resonance. This article reviews progress made in MRFM in the last decade, including the demonstration of scanned probe detection of magnetic resonance (electron spin resonance, ferromagnetic resonance, and nuclear magnetic resonance) and the mechanical detection of electron spin resonance from a single spin. Force and force-gradient approaches to mechanical detection are reviewed and recent related work using attonewton sensitivity cantilevers to probe minute fluctuating electric fields near surfaces is discussed. Given recent progress, pushing MRFM to single proton sensitivity remains an exciting possibility. We will survey some practical and fundamental issues that must be resolved to meet this challenge.

  19. Magnetic Resonance Imaging Evaluation of Cardiac Masses

    International Nuclear Information System (INIS)

    Braggion-Santos, Maria Fernanda; Koenigkam-Santos, Marcel; Teixeira, Sara Reis; Volpe, Gustavo Jardim; Trad, Henrique Simão; Schmidt, André

    2013-01-01

    Cardiac tumors are extremely rare; however, when there is clinical suspicion, proper diagnostic evaluation is necessary to plan the most appropriate treatment. In this context, cardiovascular magnetic resonance imaging (CMRI) plays an important role, allowing a comprehensive characterization of such lesions. To review cases referred to a CMRI Department for investigation of cardiac and paracardiac masses. To describe the positive case series with a brief review of the literature for each type of lesion and the role of cardiovascular magnetic resonance imaging in evaluation. Between August 2008 and December 2011, all cases referred for CMRI with suspicion of tumor involving the heart were reviewed. Cases with positive histopathological diagnosis, clinical evolution or therapeutic response compatible with the clinical suspicion and imaging findings were selected. Among the 13 cases included in our study, eight (62%) had histopathological confirmation. We describe five benign tumors (myxomas, rhabdomyoma and fibromas), five malignancies (sarcoma, lymphoma, Richter syndrome involving the heart and metastatic disease) and three non-neoplastic lesions (pericardial cyst, intracardiac thrombus and infectious vegetation). CMRI plays an important role in the evaluation of cardiac masses of non-neoplastic and neoplastic origin, contributing to a more accurate diagnosis in a noninvasive manner and assisting in treatment planning, allowing safe clinical follow-up with good reproducibility

  20. Nuclear magnetic resonance imaging method

    International Nuclear Information System (INIS)

    Johnson, G.; MacDonald, J.; Hutchison, S.; Eastwood, L.M.; Redpath, T.W.T.; Mallard, J.R.

    1984-01-01

    A method of deriving three dimensional image information from an object using nuclear magnetic resonance signals comprises subjecting the object to a continuous, static magnetic field and carrying out the following set of sequential steps: 1) exciting nuclear spins in a selected volume (90deg pulse); 2) applying non-aligned first, second and third gradients of the magnetic field; 3) causing the spins to rephase periodically by reversal of the first gradient to produce spin echoes, and applying pulses of the second gradient prior to every read-out of an echo signal from the object, to differently encode the spin in the second gradient direction for each read-out signal. The above steps 1-3 are then successively repeated with different values of gradient of the third gradient, there being a recovery interval between the repetition of successive sets of steps. Alternate echoes only are read out, the other echoes being time-reversed and ignored for convenience. The resulting signals are appropriately sampled, set out in an array and subjected to three dimensional Fourier transformation. (author)

  1. Ultrasonography, magnetic resonance imaging, radiography, and clinical assessment of inflammatory and destructive changes in fingers and toes of patients with psoriatic arthritis

    DEFF Research Database (Denmark)

    Wiell, Charlotte; Szkudlarek, Marcin; Hasselquist, Maria

    2007-01-01

    The aim of the present study was to assess ultrasonography (US) for the detection of inflammatory and destructive changes in finger and toe joints, tendons, and entheses in patients with psoriasis-associated arthritis (PsA) by comparison with magnetic resonance imaging (MRI), projection radiography...... (x-ray), and clinical findings. Fifteen patients with PsA, 5 with rheumatoid arthritis (RA), and 5 healthy control persons were examined by means of US, contrast-enhanced MRI, x-ray, and clinical assessment. Each joint of the 2nd-5th finger (metacarpophalangeal joints, proximal interphalangeal [PIP...... tendons of the fingers were assessed for the presence of insertional changes and tenosynovitis. One hand was assessed by means of MRI for the aforementioned changes. X-rays of both hands and feet were assessed for bone erosions and proliferations. US was repeated in 8 persons by another ultrasonographer...

  2. Magnetic resonance imaging for the clinical management of rectal cancer patients: recommendations from the 2012 European Society of Gastrointestinal and Abdominal Radiology (ESGAR) consensus meeting

    Energy Technology Data Exchange (ETDEWEB)

    Beets-Tan, Regina G.H. [Maastricht University Medical Centre+, Maastricht (Netherlands); Maastricht University Medical Centre+, Department of Radiology, P.O. Box 5800, AZ, Maastricht (Netherlands); Lambregts, Doenja M.J.; Maas, Monique [Maastricht University Medical Centre+, Maastricht (Netherlands); Bipat, Shandra; Stoker, Jaap [Academic Medical Centre, Amsterdam (Netherlands); Barbaro, Brunella [Catholic University School of Medicine, Rome (Italy); Caseiro-Alves, Filipe; Curvo-Semedo, Luis [Coimbra University Hospitals, Coimbra (Portugal); Fenlon, Helen M. [Mater Misericordiae University Hospital, Dublin (Ireland); Gollub, Marc J. [Memorial Sloan-Kettering Cancer Center, New York (United States); Gourtsoyianni, Sofia [University Hospital of Heraklion, Crete (Greece); Guy' s and St. Thomas' NHS FT, London (United Kingdom); Halligan, Steve; Taylor, Stuart A. [University College London, Centre for Medical Imaging, London (United Kingdom); Hoeffel, Christine [Reims University Hospital, Reims (France); Kim, Seung Ho [Inje University Haeundae Paik Hospital, Busan (Korea, Republic of); Laghi, Andrea [Sapienza - University of Rome, Rome (Italy); Maier, Andrea [Medical University of Vienna, Vienna (Austria); Rafaelsen, Soeren R. [Vejle Hospital, Vejle (Denmark); Torkzad, Michael R. [Uppsala University, Uppsala (Sweden); Blomqvist, Lennart [Karolinska University Hospital and Karolinska Institutet, Stockholm (Sweden)

    2013-09-15

    To develop guidelines describing a standardised approach regarding the acquisition, interpretation and reporting of magnetic resonance imaging (MRI) for clinical staging and restaging of rectal cancer. A consensus meeting of 14 abdominal imaging experts from the European Society of Gastrointestinal and Abdominal Radiology (ESGAR) was conducted following the RAND-UCLA Appropriateness Method. Two independent (non-voting) chairs facilitated the meeting. Two hundred and thirty-six items were scored by participants for appropriateness and classified subsequently as appropriate or inappropriate (defined by {>=} 80 % consensus) or uncertain (defined by < 80 % consensus). Items not reaching 80 % consensus were noted. Consensus was reached for 88 % of items: recommendations regarding hardware, patient preparation, imaging sequences, angulation, criteria for MRI assessment and MRI reporting were constructed from these. These expert consensus recommendations can be used as clinical guidelines for primary staging and restaging of rectal cancer using MRI. (orig.)

  3. Inhalant-Abuse Myocarditis Diagnosed by Cardiac Magnetic Resonance.

    Science.gov (United States)

    Dinsfriend, William; Rao, Krishnasree; Matulevicius, Susan

    2016-06-01

    Multiple reports of toxic myocarditis from inhalant abuse have been reported. We now report the case of a 23-year-old man found to have toxic myocarditis from inhalation of a hydrocarbon. The diagnosis was made by means of cardiac magnetic resonance imaging with delayed enhancement. The use of cardiac magnetic resonance to diagnose myocarditis has become increasingly common in clinical medicine, although there is not a universally accepted criterion for diagnosis. We appear to be the first to document a case of toxic myocarditis diagnosed by cardiac magnetic resonance. In patients with a history of drug abuse who present with clinical findings that suggest myocarditis or pericarditis, cardiac magnetic resonance can be considered to support the diagnosis.

  4. Magnetic resonance imaging of optic nerve

    International Nuclear Information System (INIS)

    Gala, Foram

    2015-01-01

    Optic nerves are the second pair of cranial nerves and are unique as they represent an extension of the central nervous system. Apart from clinical and ophthalmoscopic evaluation, imaging, especially magnetic resonance imaging (MRI), plays an important role in the complete evaluation of optic nerve and the entire visual pathway. In this pictorial essay, the authors describe segmental anatomy of the optic nerve and review the imaging findings of various conditions affecting the optic nerves. MRI allows excellent depiction of the intricate anatomy of optic nerves due to its excellent soft tissue contrast without exposure to ionizing radiation, better delineation of the entire visual pathway, and accurate evaluation of associated intracranial pathologies

  5. New magnetic resonance imaging methods in nephrology

    Science.gov (United States)

    Zhang, Jeff L.; Morrell, Glen; Rusinek, Henry; Sigmund, Eric; Chandarana, Hersh; Lerman, Lilach O.; Prasad, Pottumarthi Vara; Niles, David; Artz, Nathan; Fain, Sean; Vivier, Pierre H.; Cheung, Alfred K.; Lee, Vivian S.

    2013-01-01

    Established as a method to study anatomic changes, such as renal tumors or atherosclerotic vascular disease, magnetic resonance imaging (MRI) to interrogate renal function has only recently begun to come of age. In this review, we briefly introduce some of the most important MRI techniques for renal functional imaging, and then review current findings on their use for diagnosis and monitoring of major kidney diseases. Specific applications include renovascular disease, diabetic nephropathy, renal transplants, renal masses, acute kidney injury and pediatric anomalies. With this review, we hope to encourage more collaboration between nephrologists and radiologists to accelerate the development and application of modern MRI tools in nephrology clinics. PMID:24067433

  6. Magnetic resonance in hearing loss and vertigo

    Directory of Open Access Journals (Sweden)

    Manuel Ángel MARTÍN-PÉREZ

    2017-03-01

    Full Text Available Introduction and objective: Hearing loss and vertiginous syndrome represent an important part of the otorhinolaryngology clinic. The role of the radiologist plays in their workup become fundamental. Studies using magnetic resonance imaging (MRI are essential to guide or give the diagnosis in these cases. Method: After performing a retrospective analysis of 456 MRI studies of patients with these symptoms, we conducted a review of the main pathologies recorded that can cause these symptoms. Results: We classify into vascular disorders and other variants, tumor pathology, malformations and inflammatory pathology; We also describe the most relevant findings on MRI and illustrated with examples of our center.

  7. Lateral patellar luxation: magnetic resonance findings

    International Nuclear Information System (INIS)

    Armesto, V.; Pulpeiro, J.R.

    1995-01-01

    The objective of this article is to present the magnetic resonance (MR) findings associated with lateral patellar luxation. The series consisted of eight patients, all of whom presented joint effusion, damage to the medical retinaculum and cortical contusion or fracture of medical aspect of the patella or of anterolateral surface of the outer condyle. Five patients also presented patellar sub luxation. Diagnosis depends on the technique employed, with axial planes being very useful. Thus, it is recommended that they be used as the standard plane, especially in pathologies that are clinically unsuspicious as in this case. MR can also provide information that leads to surgical treatment rather than the standard conservative treatment. (Author)

  8. Structural magnetic resonance imaging in epilepsy

    International Nuclear Information System (INIS)

    Deblaere, Karel; Achten, Eric

    2008-01-01

    Because of its sensitivity and high tissue contrast, magnetic resonance imaging (MRI) is the technique of choice for structural imaging in epilepsy. In this review the effect of using optimised scanning protocols and the use of high field MR systems on detection sensitivity is discussed. Also, the clinical relevance of adequate imaging in patients with focal epilepsy is highlighted. The most frequently encountered MRI findings in epilepsy are reported and their imaging characteristics depicted. Imaging focus will be on the diagnosis of hippocampal sclerosis and malformations of cortical development, two major causes of medically intractable focal epilepsy. (orig.)

  9. Magnetic resonance imaging of glenohumeral joint diseases

    International Nuclear Information System (INIS)

    Kieft, G.J.; Bloem, J.L.; Obermann, W.R.; Rozing, P.; Doornbos, J.

    1987-01-01

    Through the application of oblique planes and flexible surface coil techniques, magnetic resonance imaging (MRI) promises to be of great clinical value in the evaluation of a variety of pathologic conditions affecting the shoulder. In patients with joint effusions, the tendinous portion of the rotator cuff, glenoid labrum, and bicipital tendon can be readily visualized. This capability has particular relevance in patients with inflammatory disease and traumatic conditions. Rotator cuff atrophy and impingement of the coracoacromial arc upon the supraspinatus muscle and tendon can also be demonstrated. MRI is also useful in the evaluation of shoulder instability. (orig.)

  10. Structural magnetic resonance imaging in epilepsy

    Energy Technology Data Exchange (ETDEWEB)

    Deblaere, Karel [Ghent University Hospital, Department of Neuroradiology, Ghent (Belgium); Ghent University Hospital, MR Department - 1K12, Ghent (Belgium); Achten, Eric [Ghent University Hospital, Department of Neuroradiology, Ghent (Belgium)

    2008-01-15

    Because of its sensitivity and high tissue contrast, magnetic resonance imaging (MRI) is the technique of choice for structural imaging in epilepsy. In this review the effect of using optimised scanning protocols and the use of high field MR systems on detection sensitivity is discussed. Also, the clinical relevance of adequate imaging in patients with focal epilepsy is highlighted. The most frequently encountered MRI findings in epilepsy are reported and their imaging characteristics depicted. Imaging focus will be on the diagnosis of hippocampal sclerosis and malformations of cortical development, two major causes of medically intractable focal epilepsy. (orig.)

  11. Cardiac magnetic resonance assessment of takotsubo cardiomyopathy

    International Nuclear Information System (INIS)

    Abbas, A.; Sonnex, E.; Pereira, R.S.; Coulden, R.A.

    2016-01-01

    Takotsubo cardiomyopathy is an important condition that can be difficult to differentiate from acute coronary syndrome on the basis of clinical, electrocardiogram, and cardiac enzyme assessment alone. Although coronary angiography remains important in the acute assessment of patients with suspected takotsubo cardiomyopathy, cardiac magnetic resonance (CMR) has emerged over the last decade as an important non-invasive imaging tool in the diagnosis and follow-up of this condition. We present a review highlighting the CMR features of takotsubo cardiomyopathy and its complications with particular focus on differentiating this condition from acute myocardial infarction and myocarditis.

  12. Magnetic resonance imaging of spinal diseases

    International Nuclear Information System (INIS)

    Nakatani, Mariko; Sekiya, Toru; Harada, Junta; Kawakami, Kenji; Tada, Shimpei

    1985-01-01

    Twenty-two patients were examined to determine the clinical value of magnetic resonance imaging (MRI) in the spinal disease. Using different pulse sequences T 1 value was obtained from 38 spines; the result showed that increased T 1 value indicated spinal marrow abnormalities. A comparative study of MRI and bone scintigraphy was performed in 18 patients. Although it was not feasible to evaluate effect of therapy in metastatic disease by MRI, diffuse bone marrow disease, such as diffuse bone marrow metastases and blood dyscrasia could be detected by MRI. This limited study will suggest applicability of MRI in the spinal disease. (author)

  13. Magnetic resonance imaging of the pediatric airway

    International Nuclear Information System (INIS)

    Auringer, S.T.; Bisset, G.S. III; Myer, C.M.

    1991-01-01

    Evaluation of the pediatric airway is often complex and may require multiple imaging techniques and invasive procedures. We performed magnetic resonance (MR) imaging of the airway in 34 children with clinical evidence of chronic airway obstruction and compared MR findings with those obtained by surgery and/or endoscopy. MR diagnoses included vascular compression in 15 patients, primary tracheomalacic states in 12 patients, and mediastinal masses in 4 patients. Findings were normal for 3 patients. The MR findings were in agreement with the endoscopic findings in 25 to 28 cases and in agreement with the surgical findings in 21 to 21 cases. (orig./GDG)

  14. Transition metal nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Pregosin, P.S.

    1991-01-01

    Transition metal NMR spectroscopy has progressed enormously in recent years. New methods, and specifically solid-state methods and new pulse sequences, have allowed access to data from nuclei with relatively low receptivities with the result that chemists have begun to consider old and new problems, previously unapproachable. Moreover, theory, computational science in particular, now permits the calculation of not just 13 C, 15 N and other light nuclei chemical shifts, but heavy main-group element and transition metals as well. These two points, combined with increasing access to high field pulsed spectrometer has produced a wealth of new data on the NMR transition metals. A new series of articles concerned with measuring, understanding and using the nuclear magnetic resonance spectra of the metals of Group 3-12 is presented. (author)

  15. Gaucher's disease: Magnetic resonance findings

    International Nuclear Information System (INIS)

    Roca, M.; Gomez-Pereda, R.; Blasco, A.; Ros, L.

    1996-01-01

    The objective is to assess the role of magnetic resonance (MR) in determining the initial extension of Gaucher's disease and its complications. A retrospective study of eight patients diagnosed as having Gaucher's disease was carried out using MR. The study focused on pelvis, hip, femur, spine, liver parenchyma and splenic parenchyma. Infiltration of the cancellous portion of the vertebral bodies was observed in all but one of the patients. Three patients presented small hemangiomas in dorsal and lumbar vertebral bodies. Pelvic bone involvement was homogeneous in four cases and spotty in two, while the pelvic marrow was normal in the two patients with no vertebral infiltration. A vascular necrosis of the femoral head was detected in two cases. MR is very useful in determining the initial extension, in the early diagnosis of complications and in managing the posttreatment marrow response to assess the therapeutic efficacy. 16 refs

  16. Fetal abdominal magnetic resonance imaging

    International Nuclear Information System (INIS)

    Brugger, Peter C.; Prayer, Daniela

    2006-01-01

    This review deals with the in vivo magnetic resonance imaging (MRI) appearance of the human fetal abdomen. Imaging findings are correlated with current knowledge of human fetal anatomy and physiology, which are crucial to understand and interpret fetal abdominal MRI scans. As fetal MRI covers a period of more than 20 weeks, which is characterized not only by organ growth, but also by changes and maturation of organ function, a different MR appearance of the fetal abdomen results. This not only applies to the fetal intestines, but also to the fetal liver, spleen, and adrenal glands. Choosing the appropriate sequences, various aspects of age-related and organ-specific function can be visualized with fetal MRI, as these are mirrored by changes in signal intensities. Knowledge of normal development is essential to delineate normal from pathological findings in the respective developmental stages

  17. Fetal abdominal magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Brugger, Peter C. [Center of Anatomy and Cell Biology, Integrative Morphology Group, Medical University of Vienna, Waehringerstrasse 13, 1090 Vienna (Austria)]. E-mail: peter.brugger@meduniwien.ac.at; Prayer, Daniela [Department of Radiology, Medical University of Vienna, Waehringerguertel 18-20, 1090 Vienna (Austria)

    2006-02-15

    This review deals with the in vivo magnetic resonance imaging (MRI) appearance of the human fetal abdomen. Imaging findings are correlated with current knowledge of human fetal anatomy and physiology, which are crucial to understand and interpret fetal abdominal MRI scans. As fetal MRI covers a period of more than 20 weeks, which is characterized not only by organ growth, but also by changes and maturation of organ function, a different MR appearance of the fetal abdomen results. This not only applies to the fetal intestines, but also to the fetal liver, spleen, and adrenal glands. Choosing the appropriate sequences, various aspects of age-related and organ-specific function can be visualized with fetal MRI, as these are mirrored by changes in signal intensities. Knowledge of normal development is essential to delineate normal from pathological findings in the respective developmental stages.

  18. Monitoring Crohn's disease during anti-TNF-α therapy: validation of the magnetic resonance enterography global score (MEGS) against a combined clinical reference standard

    International Nuclear Information System (INIS)

    Prezzi, Davide; Bhatnagar, Gauraang; Makanyanga, Jesica; Halligan, Steve; Taylor, Stuart Andrew; Vega, Roser

    2016-01-01

    To assess the ability of magnetic resonance enterography global score (MEGS) to characterise Crohn's disease (CD) response to anti-TNF-α therapy. Thirty-six CD patients (median age 26 years, 20 males) commencing anti-TNF-α therapy with concomitant baseline MRI enterography (MRE) were identified retrospectively. Patients' clinical course was followed and correlated with subsequent MREs. Scan order was randomised and MEGS (a global activity score) was applied by two blinded radiologists. A physician's global assessment of the disease activity (remission, mild, moderate or severe) at the time of MRE was assigned. The cohort was divided into clinical responders and non-responders and MEGS compared according to activity status and treatment response. Interobserver agreement was assessed. Median MEGS decreased significantly between baseline and first follow-up in responders (28 versus 6, P < 0.001) but was unchanged in non-responders (26 versus 18, P = 0.28). The median MEGS was significantly lower in clinical remission (9) than in moderate (14) or severe (29) activity (P < 0.001). MEGS correlated significantly with clinical activity (r = 0.53; P < 0.001). Interobserver Bland-Altman limits of agreement (BA LoA) were -19.7 to 18.5. MEGS decreases significantly in clinical responders to anti-TNF-α therapy but not in non-responders, demonstrates good interobserver agreement and moderate correlation with clinical disease activity. (orig.)

  19. Magnetic resonance cholangiopancreaticography as a diagnostic tool for common bile duct stones - A comparison with ERCP and clinical follow-up

    NARCIS (Netherlands)

    Kats, J; Kraai, M; Dijkstra, AJ; Koster, K; ter Borg, F; Hazenberg, HJA; Schattenkerk, ME; des Plantes, BGZ; Eddes, EH

    2003-01-01

    Background/Aims: The diagnostic potential of magnetic resonance cholangiopancreaticography (MRCP) has improved as a result of evolving technique. MRCP has the advantage of negligible morbidity and mortality in contrast to endoscopic retrograde cholangiopancreatography (ERCP). This study was

  20. [Surface coils for magnetic-resonance images].

    Science.gov (United States)

    Rodríguez-González, Alfredo Odón; Amador-Baheza, Ricardo; Rojas-Jasso, Rafael; Barrios-Alvarez, Fernando Alejandro

    2005-01-01

    Since the introduction of magnetic resonance imaging in Mexico, the development of this important medical imaging technology has been almost non-existing in our country. The very first surface coil prototypes for clinical applications in magnetic resonance imaging has been developed at the Center of Research in Medical Imaging and Instrumentation of the Universidad Autónoma Metropolitana Iztapalapa (Metropolitan Autonomous University, Campus Iztapalapa). Two surface coil prototypes were built: a) a circular-shaped coil and b) a square-shaped coil for multiple regions of the body, such as heart, brain, knee, hands, and ankles. These coils were tested on the 1.5T imager of the ABC Hospital-Tacubaya, located in Mexico City. Brain images of healthy volunteers were obtained in different orientations: sagittal, coronal, and axial. Since images showed a good-enough clinical quality for diagnosis, it is fair to say that these coil prototypes can be used in the clinical environment, and with small modifications, they can be made compatible with almost any commercial scanner. This type of development can offer new alternatives for further collaboration between the research centers and the radiology community, in the search of new applications and developments of this imaging technique.

  1. Magnetic resonance imaging of the prostate

    DEFF Research Database (Denmark)

    Iversen, P; Kjaer, L; Thomsen, C

    1988-01-01

    Magnetic resonance imaging offers new possibilities in investigation of the prostate gland. Current results of imaging and tissue discrimination in the evaluation of prostatic disease are reviewed. Magnetic resonance imaging may be useful in the staging of carcinoma of the prostate....

  2. Magnetic resonance imaging of the prostate

    DEFF Research Database (Denmark)

    Iversen, P; Kjaer, L; Thomsen, C

    1987-01-01

    Magnetic resonance imaging offers new possibilities in the investigation of the prostate. The current results of imaging and tissue discrimination in the evaluation of prostatic disease are reviewed. Magnetic resonance imaging may be of value in the staging of carcinoma of the prostate....

  3. Single voxel magnetic resonance spectroscopy in distinguishing ...

    African Journals Online (AJOL)

    Objective: Assess diagnostic utility of combined magnetic resonance imaging and magnetic resonance spectroscopy (MRI, MRS) in differentiating focal neoplastic lesions from focal non- neoplastic (infective or degenerative) brain lesions. Design: Descriptive, analytical - prospective study. Setting: The Aga Khan University ...

  4. Magnetic resonance: discovery, investigations, and applications

    International Nuclear Information System (INIS)

    Kessenikh, Aleksandr V

    2009-01-01

    The history of the development of the theoretical ideas and experimental methods of magnetic resonance, as well as the applications of these methods in modern natural science, technology, and medicine, are outlined, with allowance for the contribution of Russian researchers. An assessment of some promising trends of studies and applications of magnetic resonance is given. (from the history of physics)

  5. Contrast agents in magnetic resonance imaging

    International Nuclear Information System (INIS)

    Karadjian, V.

    1987-01-01

    The origine of nuclear magnetic resonance signal is reminded and different ways for contrast enhancement in magnetic resonance imaging are presented, especially, modifications of tissus relaxation times. Investigations have focused on development of agents incorporating either paramagnetic ions or stable free radicals. Pharmacological and toxicological aspects are developed. The diagnostic potential of these substances is illustrated by the example of gadolinium complexes [fr

  6. Your Radiologist Explains Magnetic Resonance Angiography (MRA)

    Medline Plus

    Full Text Available ... Sponsored by Image/Video Gallery Your Radiologist Explains Magnetic Resonance Angiography (MRA) Transcript Welcome to Radiology Info dot ... I’d like to talk with you about magnetic resonance angiography, or as it’s commonly known, MRA. MRA ...

  7. Lymphoma of uterine cervix: magnetic resonance imaging findings

    Energy Technology Data Exchange (ETDEWEB)

    Kanaan, Daniel; Constantino, Carolina Pesce Lamas; Souza, Rodrigo Canellas de, E-mail: daniel.kanaan@hotmail.com [Department of Radiology, Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil); Parente, Daniella Braz [Instituto D' Or de Pesquisa e Ensino, Rio de Janeiro, RJ (Brazil)

    2012-05-15

    Lymphoma of the cervix is a rare disease. About 1.0% to 1.5% of extranodal lymphomas originates in the female genital tract. The clinical presentation of this condition is nonspecific and magnetic resonance imaging is important for diagnostic elucidation. The present report describes the case of a 80-year-old patient with lumbar pain, whose magnetic resonance imaging showed a large uterine mass. The final diagnosis was lymphoma. (author)

  8. Diffusion and Perfusion Magnetic Resonance Imaging:Fundamentals and Advances

    OpenAIRE

    Assili, Sanam

    2016-01-01

    Over the past few decades, magnetic resonance imaging has been utilized as a powerful imaging modality to evaluate the structure and function of various organs in the human body,such as the brain. Additionally, diffusion and perfusion MR imaging have been increasingly used in neurovascular clinical applications. In diffusion-weighted magnetic resonance imaging, the mobility of water molecules is explored in order to obtain information about the microscopic behavior of the tissues. In contrast...

  9. Significance of clinical evaluation of the metacarpophalangeal joint in relation to synovial/bone pathology in rheumatoid and psoriatic arthritis detected by magnetic resonance imaging.

    Science.gov (United States)

    Stone, Millicent A; White, Lawrence M; Gladman, Dafna D; Inman, Robert D; Chaya, Sam; Lax, Matthew; Salonen, David; Weber, Deborah A; Guthrie, Judy A; Pomeroy, Emma; Podbielski, Dominik; Keystone, Edward C

    2009-12-01

    Rheumatologists base many clinical decisions regarding the management of inflammatory joint diseases on joint counts performed at clinic. We investigated the reliability and accuracy of physically examining the metacarpophalangeal (MCP) joints to detect inflammatory synovitis using magnetic resonance imaging (MRI) as the gold standard. MCP joints 2 to 5 in both hands of 5 patients with rheumatoid arthritis (RA) and 5 with psoriatic arthritis (PsA) were assessed by 5 independent examiners for joint-line swelling (visually and by palpation); joint-line tenderness by palpation (tender joint count, TJC) and stress pain; and by MRI (1.5 Tesla superconducting magnet). Interrater reliability was assessed using kappa statistics, and agreement between examination and corresponding MRI assessment was assessed by Fisher's exact tests (p 0.8) and positive predictive value (= 0.8). For PsA, significant associations exist between TJC and MRI synovitis scores (p < 0.01) and stress pain and MRI edema scores (p < 0.04). Assessment of swelling by palpation was not significantly associated with synovitis or edema as determined by MRI in RA or PsA (p = 0.54-1.0). In inflammatory arthritis, disease activity in MCP joints can be reliably assessed at the bedside by examining for joint-line tenderness (TJC) and visual inspection for swelling. Clinical assessment may have to be complemented by other methods for evaluating disease activity in the joint, such as MRI, particularly in patients with PsA.

  10. Multidimensionally encoded magnetic resonance imaging.

    Science.gov (United States)

    Lin, Fa-Hsuan

    2013-07-01

    Magnetic resonance imaging (MRI) typically achieves spatial encoding by measuring the projection of a q-dimensional object over q-dimensional spatial bases created by linear spatial encoding magnetic fields (SEMs). Recently, imaging strategies using nonlinear SEMs have demonstrated potential advantages for reconstructing images with higher spatiotemporal resolution and reducing peripheral nerve stimulation. In practice, nonlinear SEMs and linear SEMs can be used jointly to further improve the image reconstruction performance. Here, we propose the multidimensionally encoded (MDE) MRI to map a q-dimensional object onto a p-dimensional encoding space where p > q. MDE MRI is a theoretical framework linking imaging strategies using linear and nonlinear SEMs. Using a system of eight surface SEM coils with an eight-channel radiofrequency coil array, we demonstrate the five-dimensional MDE MRI for a two-dimensional object as a further generalization of PatLoc imaging and O-space imaging. We also present a method of optimizing spatial bases in MDE MRI. Results show that MDE MRI with a higher dimensional encoding space can reconstruct images more efficiently and with a smaller reconstruction error when the k-space sampling distribution and the number of samples are controlled. Copyright © 2012 Wiley Periodicals, Inc.

  11. Magnetic resonance. Gamma Rays in cardiology laboratories

    International Nuclear Information System (INIS)

    Lombardi, M.

    2001-01-01

    In recent years Cardiologists have shown an increasing interest on the use of Magnetic Resonance Imaging (MRI) for assessing cardiovascular diseases. The first generation of MRI equipment dedicated to cardiology is now available. The MRI Laboratory of Clinical Physiology Institute in Pisa has joined a multi-centric international project for the development of prototype of this dedicated machine and is currently involved in several subprojects such as the study of myocardial perfusion and the assessment of congenital heart diseases. An interdisciplinary group (cardiologists, software and hardware engineers, biologists, etc.) is full time involved in the development of new analysis algorithms, etc. The new concept of installing a MRI machine within clinical cardiovascular department has started to induce fruitful cooperations either in the research field or in the clinical setting [it

  12. Accuracy of magnetic resonance based susceptibility measurements

    Science.gov (United States)

    Erdevig, Hannah E.; Russek, Stephen E.; Carnicka, Slavka; Stupic, Karl F.; Keenan, Kathryn E.

    2017-05-01

    Magnetic Resonance Imaging (MRI) is increasingly used to map the magnetic susceptibility of tissue to identify cerebral microbleeds associated with traumatic brain injury and pathological iron deposits associated with neurodegenerative diseases such as Parkinson's and Alzheimer's disease. Accurate measurements of susceptibility are important for determining oxygen and iron content in blood vessels and brain tissue for use in noninvasive clinical diagnosis and treatment assessments. Induced magnetic fields with amplitude on the order of 100 nT, can be detected using MRI phase images. The induced field distributions can then be inverted to obtain quantitative susceptibility maps. The focus of this research was to determine the accuracy of MRI-based susceptibility measurements using simple phantom geometries and to compare the susceptibility measurements with magnetometry measurements where SI-traceable standards are available. The susceptibilities of paramagnetic salt solutions in cylindrical containers were measured as a function of orientation relative to the static MRI field. The observed induced fields as a function of orientation of the cylinder were in good agreement with simple models. The MRI susceptibility measurements were compared with SQUID magnetometry using NIST-traceable standards. MRI can accurately measure relative magnetic susceptibilities while SQUID magnetometry measures absolute magnetic susceptibility. Given the accuracy of moment measurements of tissue mimicking samples, and the need to look at small differences in tissue properties, the use of existing NIST standard reference materials to calibrate MRI reference structures is problematic and better reference materials are required.

  13. Parasellar meningiomas: magnetic resonance imaging findings

    International Nuclear Information System (INIS)

    Santos, Alair Augusto S.M.D. dos; Fontes, Cristina Asvolinsque P.

    2001-01-01

    We reviewed 22 cases of patients with parasellar meningiomas evaluated with magnetic resonance imaging (MRI) in private clinics of the cities of Niteroi and Rio de Janeiro, Rio de Janeiro State, Brazil. Our aim was to characterize the imaging findings in this type of tumor. MRI scanners with 0.5 and 1.0 Tesla magnets were used for the acquisition of multiplanar T1-weighted (pre-and post-gadolinium administration) and T2-weighted images. The main symptoms observed were headache and visual disturbances. Hyperprolactinaemia was observed in only one patient. The most frequent imaging finding was a parasellar mass which appeared hypointense on T1-weighted and hyperintense on T2-weighted images, and enhanced intensively after gadolinium administration. MRI is useful to demonstrate the lesion and to asses the damage to adjacent structures, particularly when the patient presents visual disturbances due to involvement of the cavernous sinuses. (author)

  14. Precision of 3.0 Tesla quantitative magnetic resonance imaging of cartilage morphology in a multicentre clinical trial.

    Science.gov (United States)

    Eckstein, F; Buck, R J; Burstein, D; Charles, H C; Crim, J; Hudelmaier, M; Hunter, D J; Hutchins, G; Jackson, C; Kraus, V Byers; Lane, N E; Link, T M; Majumdar, L S; Mazzuca, S; Prasad, P V; Schnitzer, T J; Taljanovic, M S; Vaz, A; Wyman, B; Le Graverand, M-P Hellio

    2008-12-01

    Quantitative MRI (qMRI) of cartilage morphology is a promising tool for disease-modifying osteoarthritis drug (DMOAD) development. Recent studies at single sites have indicated that measurements at 3.0 Tesla (T) are more reproducible (precise) than those at 1.5 T. Precision errors and stability in multicentre studies with imaging equipment from various vendors have, however, not yet been evaluated. A total of 158 female participants (97 Kellgren and Lawrence grade (KLG) 0, 31 KLG 2 and 30 KLG 3) were imaged at 7 clinical centres using Siemens Magnetom Trio and GE Signa Excite magnets. Double oblique coronal acquisitions were obtained at baseline and at 3 months, using water excitation spoiled gradient echo sequences (1.0x0.31x0.31 mm3 resolution). Segmentation of femorotibial cartilage morphology was performed using proprietary software (Chondrometrics GmbH, Ainring, Germany). The precision error (root mean square coefficient of variation (RMS CV)%) for cartilage thickness/volume measurements ranged from 2.1%/2.4% (medial tibia) to 2.9%/3.3% (lateral weight-bearing femoral condyle) across all participants. No significant differences in precision errors were observed between KLGs, imaging sites, or scanner manufacturers/types. Mean differences between baseline and 3 months ranged from <0.1% (non-significant) in the medial to 0.94% (p<0.01) in the lateral femorotibial compartment, and were 0.33% (p<0.02) for the total femorotibial subchondral bone area. qMRI performed at 3.0 T provides highly reproducible measurements of cartilage morphology in multicentre clinical trials with equipment from different vendors. The technology thus appears sufficiently robust to be recommended for large-scale multicentre trials.

  15. Single voxel magnetic resonance spectroscopy at 3 Tesla in a memory disorders clinic: early right hippocampal NAA/Cr loss in mildly impaired subjects.

    Science.gov (United States)

    Caserta, Maria T; Ragin, Ann; Hermida, Adriana P; Ahrens, R John; Wise, Leon

    2008-11-30

    In this study, we use magnetic resonance spectroscopy (MRS) at 3 Tesla to measure N-acetyl aspartate (NAA), myo-inositol (mI) and choline (Cho) to creatine (Cr) ratios in R (right) and L (left) hippocampi (H) in 8 mildly memory impaired (MMI), 6 probable Alzheimer's Disease (PRAD), and 17 control subjects. NAA/Cr was significantly reduced in the RH in the MMI group and bilaterally in the PRAD group vs. controls. No other metabolite differences were noted between the three groups. Five MMI subjects have converted to PRAD in follow-up. These findings suggest that RH NAA/Cr ratios measured at 3 Tesla may be a sensitive marker of future progression to dementia in a clinically defined population with isolated memory complaints.

  16. Clinical relevance and indications for cardiac magnetic resonance imaging 2013. An interdisciplinary expert statement; Klinischer Stellenwert und Indikationen zur Magnetresonanztomografie des Herzens 2013. Ein interdisziplinaeres Expertenstatement

    Energy Technology Data Exchange (ETDEWEB)

    Hergan, Klaus [Universitaetsklinikum Salzburg (Austria). Universitaetsinst. fuer Radiologie; Globits, S. [Herz-Kreislauf-Zentrum Gross Gerungs (Austria); Schuchlenz, H. [Landeskrankenhaus Graz-West (Austria). Dept. fuer Kardiologie/Intensivmedizin] [and others

    2013-03-15

    During the last years the indications of Cardiac Magnetic Resonance Imaging (CMRI) have been continuously expanded. However, the acceptance of the method by cardiologists and radiologists does not correlate with respect to the diagnostic potential. Several factors, such as expensive equipment, relatively long examination times, high technical know how and lack of remuneration, limit the application of CMRI in everyday clinical practice. Furthermore, doctors tend to apply more conventional, well established diagnostic procedures, the access to the method is still limited and there exist difficulties in the interdisciplinary collaboration. The interdisciplinary Austrian approach to Cardiac Imaging is aimed to improve the aforementioned problems and to support the implementation of CMRI in the diagnostic tree of cardiac diseases thus enabling a cost efficient management of patients in cardiology. (orig.)

  17. Nuclear magnetic resonance in cardiology: cardiac MRI

    International Nuclear Information System (INIS)

    Fernandez, Claudio C.

    2003-01-01

    As a new gold standard for mass, volume and flow, the magnetic resonance imaging (MRI) is probably the most rapidly evolving technique in the cardiovascular diagnosis. An integrated cardiac MRI examination allows the evaluation of morphology, global and regional function, coronary anatomy, perfusion, viability and myocardial metabolism, all of them in only one diagnostic test and in a totally noninvasive manner. The surgeons can obtain relevant information on all aspects of diseases of the heart and great vessels, which include anatomical details and relationships with the greatest field of view, and may help to reduce the number of invasive procedures required in pre and postoperative evaluation. However, despite these excellent advantages the present clinical utilization of MRI is still too often restricted to few pathologies or case studies in which other techniques fail to identify the cardiac or cardiovascular abnormalities. If magnetic resonance is an excellent method for diagnosing so many different cardiac conditions, why is so little it used in routine cardiac practice? Cardiologists are still not very familiar with the huge possibilities or cardiovascular MRI utilities. Our intention is to give a comprehensive survey of many of the clinical applications of this challenger technique in the study of the heart and great vessels. Those who continue to ignore this important and mature imaging technique will rightly fail to benefit. (author) [es

  18. The adult spinal cord injury without radiographic abnormalities syndrome: magnetic resonance imaging and clinical findings in adults with spinal cord injuries having normal radiographs and computed tomography studies.

    Science.gov (United States)

    Kasimatis, Georgios B; Panagiotopoulos, Elias; Megas, Panagiotis; Matzaroglou, Charalambos; Gliatis, John; Tyllianakis, Minos; Lambiris, Elias

    2008-07-01

    Spinal cord injury without radiographic abnormalities (SCIWORA) is thought to represent mostly a pediatric entity and its incidence in adults is rather underreported. Some authors have also proposed the term spinal cord injury without radiologic evidence of trauma, as more precisely describing the condition of adult SCIWORA in the setting of cervical spondylosis. The purpose of the present study was to evaluate adult patients with cervical spine injuries and radiological-clinical examination discrepancy, and to discuss their characteristics and current management. During a 16-year period, 166 patients with a cervical spine injury were admitted in our institution (Level I trauma center). Upper cervical spine injuries (occiput to C2, 54 patients) were treated mainly by a Halo vest, whereas lower cervical spine injuries (C3-T1, 112 patients) were treated surgically either with an anterior, or posterior procedure, or both. Seven of these 166 patients (4.2%) had a radiologic-clinical mismatch, i.e., they presented with frank spinal cord injury with no signs of trauma, and were included in the study. Magnetic resonance imaging was available for 6 of 7 patients, showing intramedullary signal changes in 5 of 6 patients with varying degrees of compression from the disc and/or the ligamentum flavum, whereas the remaining patient had only traumatic herniation of the intervertebral disc and ligamentum flavum bulging. Follow-up period was 6.4 years on average (1-10 years). This retrospective chart review provides information on adult patients with cervical spinal cord injuries whose radiographs and computed tomography studies were normal. It furthers reinforces the pathologic background of SCIWORA in an adult population, when evaluated by magnetic resonance imaging. Particularly for patients with cervical spondylosis, special attention should be paid with regard to vascular compromise by predisposing factors such as smoking or vascular disease, since they probably contribute in

  19. Bi-exponential T2 analysis of healthy and diseased Achilles tendons: an in vivo preliminary magnetic resonance study and correlation with clinical score.

    Science.gov (United States)

    Juras, Vladimir; Apprich, Sebastian; Szomolanyi, Pavol; Bieri, Oliver; Deligianni, Xeni; Trattnig, Siegfried

    2013-10-01

    To compare mono- and bi-exponential T2 analysis in healthy and degenerated Achilles tendons using a recently introduced magnetic resonance variable-echo-time sequence (vTE) for T2 mapping. Ten volunteers and ten patients were included in the study. A variable-echo-time sequence was used with 20 echo times. Images were post-processed with both techniques, mono- and bi-exponential [T2 m, short T2 component (T2 s) and long T2 component (T2 l)]. The number of mono- and bi-exponentially decaying pixels in each region of interest was expressed as a ratio (B/M). Patients were clinically assessed with the Achilles Tendon Rupture Score (ATRS), and these values were correlated with the T2 values. The means for both T2 m and T2 s were statistically significantly different between patients and volunteers; however, for T2 s, the P value was lower. In patients, the Pearson correlation coefficient between ATRS and T2 s was -0.816 (P = 0.007). The proposed variable-echo-time sequence can be successfully used as an alternative method to UTE sequences with some added benefits, such as a short imaging time along with relatively high resolution and minimised blurring artefacts, and minimised susceptibility artefacts and chemical shift artefacts. Bi-exponential T2 calculation is superior to mono-exponential in terms of statistical significance for the diagnosis of Achilles tendinopathy. • Magnetic resonance imaging offers new insight into healthy and diseased Achilles tendons • Bi-exponential T2 calculation in Achilles tendons is more beneficial than mono-exponential • A short T2 component correlates strongly with clinical score • Variable echo time sequences successfully used instead of ultrashort echo time sequences.

  20. Functionalized Magnetic Resonance Contrast Agent Selectively Binds to Glycoprotein IIb/IIIa on Activated Human Platelets under Flow Conditions and Is Detectable at Clinically Relevant Field Strengths

    Directory of Open Access Journals (Sweden)

    Constantin von zur Mühlen

    2008-03-01

    Full Text Available Recent progress in molecular magnetic resonance imaging (MRI provides the opportunity to image cells and cellular receptors using microparticles of iron oxide (MPIOs. However, imaging targets on vessel walls remains challenging owing to the quantity of contrast agents delivered to areas of interest under shear stress conditions. We evaluated ex vivo binding characteristics of a functional MRI contrast agent to ligand-induced binding sites (LIBSs on activated glycoprotein IIb/IIIa receptors of human platelets, which were lining rupture-prone atherosclerotic plaques and could therefore facilitate detection of platelet-mediated pathology in atherothrombotic disease. MPIOs were conjugated to anti-LIBS single-chain antibodies (LIBS-MPIO or control antibodies (control MPIO. Ex vivo binding to human platelet-rich clots in a dose-dependent manner was confirmed on a 3 T clinical MRI scanner and by histology (p < .05 for LIBS-MPIO vs control MPIO. By using a flow chamber setup, significant binding of LIBS-MPIO to a platelet matrix was observed under venous and arterial flow conditions, but not for control MPIO (p < .001. A newly generated MRI contrast agent detects activated human platelets at clinically relevant magnetic field strengths and binds to platelets under venous and arterial flow conditions, conveying high payloads of contrast to specific molecular targets. This may provide the opportunity to identify vulnerable, rupture-prone atherosclerotic plaques via noninvasive MRI.

  1. Force detection of nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Rugar, D.; Zueger, O.; Hoen, S.; Yannoni, C.S.; Vieth, H.M.; Kendrick, R.D.

    1994-01-01

    Micromechanical sensing of magnetic force was used to detect nuclear magnetic resonance with exceptional sensitivity and spatial resolution. With a 900 angstrom thick silicon nitride cantilever capable of detecting subfemtonewton forces, a single shot sensitivity of 1.6 x 10 13 protons was achieved for an ammonium nitrate sample mounted on the cantilever. A nearby millimeter-size iron particle produced a 600 tesla per meter magnetic field gradient, resulting in a spatial resolution of 2.6 micrometers in one dimension. These results suggest that magnetic force sensing is a viable approach for enhancing the sensitivity and spatial resolution of nuclear magnetic resonance microimaging

  2. A review of magnetic resonance imaging in spinal trauma

    International Nuclear Information System (INIS)

    Davis, S.J.; Khangure, M.S.

    1994-01-01

    One hundred and ninety-five magnetic resonance (MR) images of 167 patients with neurological impairment following spinal trauma were reviewed. Acute cord injury produces central haemorrhagic necrosis that extends transversely and longitudinally with time and increased injury severity. Oedema appears more homogeneous, extensive and dominant in minimal lesions. Magnetic resonance appearances correlate with neurological status and outcome. Patients with MR evidence of cord blood had severe clinical lesions and failed to show useful clinical improvement. Patients with homogeneous 'oedema' improved to useful function. Lesion signal inhomogeneity relates to a worse prognosis. The clinical level correlates closely with cord blood or signal in homogeneity but imprecisely with homogeneous oedema. Disc herniations require differentiation from epidural blood and venous engorgement, which are prominent with bone displacement. Magnetic resonance is recommended in incomplete cord syndromes and in cord injuries with no apparent fracture, particularly of clinically deteriorating. 18 ref., 2 figs., 3 tabs

  3. Feasibility of studying brain morphology in major depressive disorder with structural magnetic resonance imaging and clinical data from the electronic medical record: A pilot study

    Science.gov (United States)

    Hoogenboom, Wouter S.; Perlis, Roy H.; Smoller, Jordan W.; Zeng-Treitler, Qing; Gainer, Vivian S.; Murphy, Shawn N.; Churchill, Susanne E.; Kohane, Isaac S.; Shenton, Martha E.; Iosifescu, Dan V.

    2012-01-01

    For certain research questions related to long-term outcomes or to rare disorders, designing prospective studies is impractical or prohibitively expensive. Such studies could instead utilize clinical and magnetic resonance imaging data (MRI) collected as part of routine clinical care, stored in the electronic medical record (EMR). Using major depressive disorder (MDD) as a disease model, we examined the feasibility of studying brain morphology and associations with remission using clinical and MRI data exclusively drawn from the EMR. Advanced automated tools were used to select MDD patients and controls from the EMR who had brain MRI data, but no diagnosed brain pathology. MDD patients were further assessed for remission status by review of clinical charts. Twenty MDD patients (eight full-remitters, six partial-remitters, and six non-remitters), and fifteen healthy control subjects met all study criteria for advanced morphometric analyses. Compared to controls, MDD patients had significantly smaller right rostral-anterior cingulate volume, and level of non-remission was associated with smaller left hippocampus and left rostral-middle frontal gyrus volume. The use of EMR data for psychiatric research may provide a timely and cost-effective approach with the potential to generate large study samples reflective of the real population with the illness studied. PMID:23149041

  4. Comparison of the clinical state and its changes in patients with Duchenne and Becker muscular dystrophy with results of in vivo 31P magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Hajek, M.; Grosmanova, A.; Horska, A.; Urban, P.

    1993-01-01

    A total of 14 boys with the Duchenne and Becker forms of muscular dystrophy (DMD, BMD) were examined using 31 P magnetic resonance (MR) spectroscopy; 12 boys were examined repeatedly. The results were correlated with clinical findings (including those of genetic tests) and with data obtained from examinations of an age-matched control group. Evaluation of results using principal component analysis revealed maximum variability in the following ratios: phosphocreatine/inorganic phosphate (PCr/Pi), phosphocreatine/phosphodiesters (PCr/PDe) and phosphocreatine/phosphomonoesters (PCr/PMe). A decrease in PCr/Pi correlates with weakness of the hip girdle and of the lower part of the shoulder girdle in DMD/BMD patients. The values of all ratios in the group of patients with the DMD phenotype differ significantly from results obtained in the group with the BMD phenotype. Continuous follow-up of patients using 31 P MR spectroscopy revealed a marked decrease in PCr/Pi in DMD/BMD patients at an age that could be expected in subjects with a typical clinical course of DMD/BMD. An attempt to manage a concomitant disease with prednisone and carnitene was followed by an increase in PCr/Pi in 3 cases. A rise in the PCr/Pi ratio signalled clinical improvement in the patients. A decrease in PCr/Pi was found after controlled physical training, a finding consistent with data obtained from clinical observations describing an adverse effect of physical stress on the dystrophic process. (orig.)

  5. Comparison of the clinical state and its changes in patients with Duchenne and Becker muscular dystrophy with results of in vivo {sup 31}P magnetic resonance spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Hajek, M [MR Unit, Inst. for Clinical and Experimental Medicine, Prague (Czech Republic); Grosmanova, A [Dept. of Neuropediatrics, Thomayer` s Hospital, Prague (Czech Republic); Horska, A [MR Unit, Inst. for Clinical and Experimental Medicine, Prague (Czech Republic); Urban, P [Dept. of Analytical Chemistry, Prague Inst. of Chemical Technology (Czech Republic)

    1993-12-01

    A total of 14 boys with the Duchenne and Becker forms of muscular dystrophy (DMD, BMD) were examined using {sup 31}P magnetic resonance (MR) spectroscopy; 12 boys were examined repeatedly. The results were correlated with clinical findings (including those of genetic tests) and with data obtained from examinations of an age-matched control group. Evaluation of results using principal component analysis revealed maximum variability in the following ratios: phosphocreatine/inorganic phosphate (PCr/Pi), phosphocreatine/phosphodiesters (PCr/PDe) and phosphocreatine/phosphomonoesters (PCr/PMe). A decrease in PCr/Pi correlates with weakness of the hip girdle and of the lower part of the shoulder girdle in DMD/BMD patients. The values of all ratios in the group of patients with the DMD phenotype differ significantly from results obtained in the group with the BMD phenotype. Continuous follow-up of patients using {sup 31}P MR spectroscopy revealed a marked decrease in PCr/Pi in DMD/BMD patients at an age that could be expected in subjects with a typical clinical course of DMD/BMD. An attempt to manage a concomitant disease with prednisone and carnitene was followed by an increase in PCr/Pi in 3 cases. A rise in the PCr/Pi ratio signalled clinical improvement in the patients. A decrease in PCr/Pi was found after controlled physical training, a finding consistent with data obtained from clinical observations describing an adverse effect of physical stress on the dystrophic process. (orig.)

  6. Extent of silent cerebral infarcts in adult sickle-cell disease patients on magnetic resonance imaging: is there a correlation with the clinical severity of disease?

    Directory of Open Access Journals (Sweden)

    Ekaterini Solomou

    2013-02-01

    Full Text Available The aim of this paper is to correlate the extent of silent cerebral infarcts (SCIs on magnetic resonance imaging (MRI with the clinical severity of sickle cell disease (SCD in adult patients. Twenty-four consecutive adult asymptomatic SCD patients (11 male and 13 female with a mean age of 38.4 years (range 20-59 were submitted to brain MRI on a 1 Tesla Gyroscan Intera, Philips MR scanner with a dedicated head coil. The protocol consisted of TSE T2-weighted and FLAIR images on the axial and coronal planes. MRI readings were undertaken by two radiologists and consensus readings. Patients were compound heterozygotes (HbS/β-thal. The extent of SCIs was classified from 0-2 with 0 designating no lesions. Clinical severity was graded as 0-2 by the hematologist, according to the frequency and severity of vaso-occlusive crises. There was no statistically significant correlation between the severity of clinical disease and the extent of SCIs on MR imaging. The extent of SCI lesions did not differ statistically between younger and older patients. Patients receiving hydroxyurea had no statistically significant difference in the extent of SCI lesions. The extent of SCIs in heterozygous (HbS/β-thal SCD patients is not age related and may be quite severe even in younger (<38.4 years patients. However the extent of SCIs is not correlated with the severity of clinical disease.

  7. Magnetic resonance elastometry using a single-sided permanent magnet

    International Nuclear Information System (INIS)

    Tan, Carl S; Marble, Andrew E; Ono, Yuu

    2012-01-01

    In this paper, we describe a magnetic resonance method of measuring material elasticity using a single-sided magnet with a permanent static field gradient. This method encodes sample velocity in a reciprocal space using Hahn spin-echoes with variable timing. The experimental results show a strong correlation between magnetic resonance signal attenuation and elasticity when an oscillating force is applied on the sample. This relationship in turn provides us with information about the displacement velocity experienced by the sample, which is inversely proportional to Young's modulus. The proposed method shows promise in offering a portable and cost-effective magnetic resonance elastography system. (paper)

  8. Artifacts in Magnetic Resonance Imaging

    International Nuclear Information System (INIS)

    Krupa, Katarzyna; Bekiesińska-Figatowska, Monika

    2015-01-01

    Artifacts in magnetic resonance imaging and foreign bodies within the patient’s body may be confused with a pathology or may reduce the quality of examinations. Radiologists are frequently not informed about the medical history of patients and face postoperative/other images they are not familiar with. A gallery of such images was presented in this manuscript. A truncation artifact in the spinal cord could be misinterpreted as a syrinx. Motion artifacts caused by breathing, cardiac movement, CSF pulsation/blood flow create a ghost artifact which can be reduced by patient immobilization, or cardiac/respiratory gating. Aliasing artifacts can be eliminated by increasing the field of view. An artificially hyperintense signal on FLAIR images can result from magnetic susceptibility artifacts, CSF/vascular pulsation, motion, but can also be found in patients undergoing MRI examinations while receiving supplemental oxygen. Metallic and other foreign bodies which may be found on and in patients’ bodies are the main group of artifacts and these are the focus of this study: e.g. make-up, tattoos, hairbands, clothes, endovascular embolization, prostheses, surgical clips, intraorbital and other medical implants, etc. Knowledge of different types of artifacts and their origin, and of possible foreign bodies is necessary to eliminate them or to reduce their negative influence on MR images by adjusting acquisition parameters. It is also necessary to take them into consideration when interpreting the images. Some proposals of reducing artifacts have been mentioned. Describing in detail the procedures to avoid or limit the artifacts would go beyond the scope of this paper but technical ways to reduce them can be found in the cited literature

  9. Magnetic resonance in obstructive jaundice

    International Nuclear Information System (INIS)

    Gupta, R.K.; Jena, A.; Khushu, S.; Kakar, A.K.; Mishra, P.K.

    1989-01-01

    Twelve cases of obstructive jaundice in whom ultrasound failed to demonstrate the site and/or the cause of obstruction of the biliary tract were examined with magnetic resonance imaging (MRI), correctly diagnosing the site and cause of obstruction in 10 of 12 surgically proven cases. In one case of cholangiocarcinoma, the site of obstruction was well shown on MR but a definite cause could not be ascertained. In another patient who developed intermittent jaundice following surgery for choledochal cyst, MR demonstrated a solitary stone in the common hepatic duct. Surgical confirmation could not be achieved as the patient was lost to follow up. There were 6 cases of choledocholithiasis, 3 cases of gall bladder carcinoma and one case each of pancreatic adenocarcinoma and cholangiocarcinoma. It is believed that MRI will provide obstructive jaundice and will be able to minimize the use of percutaneous transhepatic cholangiography (PTC) and endoscopic retrograde cholangiopancreatography (ERCP) in view of its ability to perform multiplanar imaging in multiple sequences. 11 refs., figs., 1 tab

  10. Low rank magnetic resonance fingerprinting.

    Science.gov (United States)

    Mazor, Gal; Weizman, Lior; Tal, Assaf; Eldar, Yonina C

    2016-08-01

    Magnetic Resonance Fingerprinting (MRF) is a relatively new approach that provides quantitative MRI using randomized acquisition. Extraction of physical quantitative tissue values is preformed off-line, based on acquisition with varying parameters and a dictionary generated according to the Bloch equations. MRF uses hundreds of radio frequency (RF) excitation pulses for acquisition, and therefore high under-sampling ratio in the sampling domain (k-space) is required. This under-sampling causes spatial artifacts that hamper the ability to accurately estimate the quantitative tissue values. In this work, we introduce a new approach for quantitative MRI using MRF, called Low Rank MRF. We exploit the low rank property of the temporal domain, on top of the well-known sparsity of the MRF signal in the generated dictionary domain. We present an iterative scheme that consists of a gradient step followed by a low rank projection using the singular value decomposition. Experiments on real MRI data demonstrate superior results compared to conventional implementation of compressed sensing for MRF at 15% sampling ratio.

  11. Myositis ossificans: magnetic resonance images

    International Nuclear Information System (INIS)

    Dosda, R.; Marti-Bonmati, L.; Concepcion, L.; Galant, J.

    1999-01-01

    Myositis ossificans is characterized by a benign, self-limiting, ossifying mass of the white tissue. In the present report, we describe the magnetic resonance (MR) images in three cases of myositis ossificans in pediatric patients, correlating the MR findings with those obtained with other radiological studies. The lesions were detected in three patients, two boys and one girl, ranging in age between 10 and 14 years. The nature of the lesion was confirmed histologically in all three cases. The MR images were obtained using superconductive units at 0.5 Teslas, with T1 and T2-weighted spin-echo and STIR sequences. In two patients, gadolinium-enhanced T1-weighted images were also obtained. As in any process of maturation, the proliferation/maturation ratio depends on the moment in the course of the lesion, which affects its MR features,. In acute phases, the soft tissue mass with an intraosseous, perilesional adematous reaction predominates, while annular calcification and lesser edema are characteristic of subacute episode. Myositis ossificans is very rare in children. The inflammatory response may present a radiological pattern difficult to distinguish from that of aggressive tumor or infection, especially in the acute phase. (Author) 7 refs

  12. Italian registry of cardiac magnetic resonance

    Energy Technology Data Exchange (ETDEWEB)

    Francone, Marco [Department of Radiological, Oncological and Pathological Sciences, Sapienza University of Rome (Italy); Di Cesare, Ernesto, E-mail: ernesto.dicesare@cc.univaq.it [Dipartimento di Scienze Cliniche Applicate e Biotecnologie, Università di L’Aquila (Italy); Cademartiri, Filippo [Cardio-Vascular Imaging Unit, Giovanni XXIII Hospital, Monastier di Treviso, TV (Italy); Erasmus Medical Center University, Rotterdam (Netherlands); Pontone, Gianluca [IRCCS Centro Cardiologico Monzino (Italy); Lovato, Luigi [Policlinico S. Orsola Bologna (Italy); Matta, Gildo [Azienda ospedaliera G Brotzu Cagliari (Italy); Secchi, Francesco [IRCCS Policlinico San Donato, Radiology Unit, Milan (Italy); Maffei, Erica [Cardio-Vascular Imaging Unit, Giovanni XXIII Hospital, Monastier di Treviso, TV (Italy); Erasmus Medical Center University, Rotterdam (Netherlands); Pradella, Silvia [Azienda Ospedaliera Universitaria Careggi (Italy); Carbone, Iacopo [Department of Radiological, Oncological and Pathological Sciences, Sapienza University of Rome (Italy); Marano, Riccardo [Policlinico Gemelli, Università Cattolica Roma (Italy); Bacigalupo, Lorenzo [Ospedale Galliera, Genova (Italy); Chiodi, Elisabetta [Ospedale S. Anna Ferrara (Italy); Donato, Rocco [Azienda Ospedaliera Universitaria G. Martino, Me (Italy); Sbarbati, Stefano [Ospedale Madre Giuseppina Vannini, Roma (Italy); De Cobelli, Francesco [IRCCS S. Raffaele, Università Vita Salute, Milano (Italy); Di Renzi, Paolo [Fate Bene Fratelli Isola tiberina, Roma (Italy); Ligabue, Guido; Mancini, Andrea [Azienda Ospedaliera-Universitaria Policlinico di Modena (Italy); Palmieri, Francesco [Diparimento di Diagnostica per immagini e radiologia interventistica, Ospedale S. Maria delle Grazie, Pozzuoli, Napoli (Italy); and others

    2014-01-15

    Objectives: Forty sites were involved in this multicenter and multivendor registry, which sought to evaluate indications, spectrum of protocols, impact on clinical decision making and safety profile of cardiac magnetic resonance (CMR). Materials and methods: Data were prospectively collected on a 6-month period and included 3376 patients (47.2 ± 19 years; range 1–92 years). Recruited centers were asked to complete a preliminary general report followed by a single form/patient. Referral physicians were not required to exhibit any specific certificate of competency in CMR imaging. Results: Exams were performed with 1.5 T scanners in 96% of cases followed by 3 T (3%) and 1 T (1%) magnets and contrast was administered in 84% of cases. The majority of cases were performed for the workup of inflammatory heart disease/cardiomyopathies representing overall 55.7% of exams followed by the assessment of myocardial viability and acute infarction (respectively 6.9% and 5.9% of patients). In 49% of cases the final diagnosis provided was considered relevant and with impact on patient's clinical/therapeutic management. Safety evaluation revealed 30 (0.88%) clinical events, most of which due to patient's preexisting conditions. Radiological reporting was recorded in 73% of exams. Conclusions: CMR is performed in a large number of centers in Italy with relevant impact on clinical decision making and high safety profile.

  13. Chest magnetic resonance imaging: a protocol suggestion

    Directory of Open Access Journals (Sweden)

    Bruno Hochhegger

    2015-12-01

    Full Text Available Abstract In the recent years, with the development of ultrafast sequences, magnetic resonance imaging (MRI has been established as a valuable diagnostic modality in body imaging. Because of improvements in speed and image quality, MRI is now ready for routine clinical use also in the study of pulmonary diseases. The main advantage of MRI of the lungs is its unique combination of morphological and functional assessment in a single imaging session. In this article, the authors review most technical aspects and suggest a protocol for performing chest MRI. The authors also describe the three major clinical indications for MRI of the lungs: staging of lung tumors; evaluation of pulmonary vascular diseases; and investigation of pulmonary abnormalities in patients who should not be exposed to radiation.

  14. Magnetic resonance tomography and ultrasound in rheumatology

    International Nuclear Information System (INIS)

    Kainberger, F.; Czerny, C.; Trattnig, S.; Lack, W.; Machold, K.; Graninger, W.

    1996-01-01

    Technical innovations and software improvements in magnetic resonance imaging (MRI) and high-resolution sonography (US) have definitely influenced the diagnostic imaging of rheumatic diseases. For MRI, improvements in surface coils, dedicated low-field systems (0.2 T), and software improvements (shorter acquisition times and refinements of fat suppressing techniques) must be mentioned. For sonography, the main innovations concern the development of higher transducer frequencies (7-15 Mhz) and power Doppler imaging. Clinical evaluations have shown that MRI and US are most useful in cases of suspected rheumatic disease with negative plain film radiographs and for documenting the course of the disease, diagnosing of early rheumatoid arthritis, making a differential diagnosis in clinically unclear rheumatic diseases, investigating vascularization, and quantifying pannus formation. In order to improve diagnostic efficacy the role of MRI and US in the management of patients with rheumatic disease should be reconsidered. (orig.) [de

  15. NMR magnetic field controller for pulsed nuclear magnetic resonance experiments

    International Nuclear Information System (INIS)

    Scheler, G.; Anacker, M.

    1975-01-01

    A nuclear magnetic resonance controller for magnetic fields, which can also be used for pulsed NMR investigations, is described. A longtime stability of 10 -7 is achieved. The control signal is generated by a modified time sharing circuit with resonance at the first side band of the 2 H signal. An exact calibration of the magnetic field is achieved by the variation of the H 1 - or of the time-sharing frequency. (author)

  16. A Magnetic Resonance Measurement Technique for Rapidly Switched Gradient Magnetic Fields in a Magnetic Resonance Tomograph

    Directory of Open Access Journals (Sweden)

    K. Bartušek

    2003-01-01

    Full Text Available This paper describes a method for measuring of the gradient magnetic field in Nuclear Magnetic Resonance (NMR tomography, which is one of the modern medical diagnostic methods. A very important prerequisite for high quality imaging is a gradient magnetic field in the instrument with exactly defined properties. Nuclear magnetic resonance enables us to measure the pulse gradient magnetic field characteristics with high accuracy. These interesting precise methods were designed, realised, and tested at the Institute of Scientific Instruments (ISI of the Academy of Sciences of the Czech Republic. The first of them was the Instantaneous Frequency (IF method, which was developed into the Instantaneous Frequency of Spin Echo (IFSE and the Instantaneous Frequency of Spin Echo Series (IFSES methods. The above named methods are described in this paper and their a comparison is also presented.

  17. State of the art magnetic resonance imaging

    International Nuclear Information System (INIS)

    Weissman, J.D.

    1987-01-01

    In less than a decade Magnetic Resonance Imaging (MRI) has evolved from a laboratory demonstration to a safe and effective technique for clinical diagnosis. This evolutionary process continues. At this time 2-D and 3-D imaging of the head and body is firmly established in clinical use. Surface coil imaging, two-component chemical shift imaging, in-vivo spectroscopy and flow imaging are currently in various stages of development. The present state of the art of MRI is a function of an array of technologies: magnet, Rf coil, Rf pulse amplifier, gradient coil and driver, pulse programmer, A/D converter, computer system architecture, array processors and mass storage (both magnetic and optical). The overall product design is the result of a complex process which balances the advantages and disadvantages of each component for optimal system performance and flexibility. The author discusses the organization of a state-of-the-art MRI system. Several examples of the kinds of system interactions affecting design choices are given. (Auth.)

  18. Spatial localization in nuclear magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Keevil, Stephen F

    2006-01-01

    The ability to select a discrete region within the body for signal acquisition is a fundamental requirement of in vivo NMR spectroscopy. Ideally, it should be possible to tailor the selected volume to coincide exactly with the lesion or tissue of interest, without loss of signal from within this volume or contamination with extraneous signals. Many techniques have been developed over the past 25 years employing a combination of RF coil properties, static magnetic field gradients and pulse sequence design in an attempt to meet these goals. This review presents a comprehensive survey of these techniques, their various advantages and disadvantages, and implications for clinical applications. Particular emphasis is placed on the reliability of the techniques in terms of signal loss, contamination and the effect of nuclear relaxation and J-coupling. The survey includes techniques based on RF coil and pulse design alone, those using static magnetic field gradients, and magnetic resonance spectroscopic imaging. Although there is an emphasis on techniques currently in widespread use (PRESS, STEAM, ISIS and MRSI), the review also includes earlier techniques, in order to provide historical context, and techniques that are promising for future use in clinical and biomedical applications. (topical review)

  19. Audit of a policy of magnetic resonance imaging with diffusion-weighted imaging as first-line neuroimaging for in-patients with clinically suspected acute stroke

    International Nuclear Information System (INIS)

    Buckley, B.T.; Wainwright, A.; Meagher, T.; Briley, D.

    2003-01-01

    AIM: To audit the feasibility and use of diffusion-weighted (DW) magnetic resonance imaging (MRI) as initial neuroimaging for in-patients with clinically suspected acute stroke. MATERIALS AND METHODS: In April 2000, MRI with DW and T2-weighted sequence was locally instituted as initial neuroimaging for patients with clinically suspected acute stroke. This retrospective study reviewed imaging performed for in-patients with suspected acute stroke over a 9-month period. Data were collected on image type, result and need for repeat imaging. RESULTS: During the study period, 124 patients had neuroimaging for suspected cerebrovascular accident, and 119 were MRI safe. Eighty-eight (73.9%) patients underwent DW MRI as first-line investigation. Five patients were not MRI safe and 31 had computed tomography (CT) as first-line imaging due to lack of available MRI capacity. Repeat neuroimaging was performed in 16 (12.9%) patients. Study times were comparable for both types of neuroimaging: a mean of 13 min for MRI and 11 min for CT. CONCLUSION: The audit standard was achieved in 88 (73.9%) patients. The use of DW MRI as a first-line investigation for patients with a clinical diagnosis of acute stroke is achievable in a district general hospital setting

  20. Clinical validation of semi-automated software for volumetric and dynamic contrast enhancement analysis of soft tissue venous malformations on magnetic resonance imaging examination

    Energy Technology Data Exchange (ETDEWEB)

    Caty, Veronique [Hopital Maisonneuve-Rosemont, Universite de Montreal, Department of Radiology, Montreal, QC (Canada); Kauffmann, Claude; Giroux, Marie-France; Oliva, Vincent; Therasse, Eric [Centre Hospitalier de l' Universite de Montreal (CHUM), Universite de Montreal and Research Centre, CHUM (CRCHUM), Department of Radiology, Montreal, QC (Canada); Dubois, Josee [Centre Hospitalier Universitaire Sainte-Justine et Universite de Montreal, Department of Radiology, Montreal, QC (Canada); Mansour, Asmaa [Institut de Cardiologie de Montreal, Heart Institute Coordinating Centre, Montreal, QC (Canada); Piche, Nicolas [Object Research System, Montreal, QC (Canada); Soulez, Gilles [Centre Hospitalier de l' Universite de Montreal (CHUM), Universite de Montreal and Research Centre, CHUM (CRCHUM), Department of Radiology, Montreal, QC (Canada); CHUM - Hopital Notre-Dame, Department of Radiology, Montreal, Quebec (Canada)

    2014-02-15

    To evaluate venous malformation (VM) volume and contrast-enhancement analysis on magnetic resonance imaging (MRI) compared with diameter evaluation. Baseline MRI was undertaken in 44 patients, 20 of whom were followed by MRI after sclerotherapy. All patients underwent short-tau inversion recovery (STIR) acquisitions and dynamic contrast assessment. VM diameters in three orthogonal directions were measured to obtain the largest and mean diameters. Volumetric reconstruction of VM was generated from two orthogonal STIR sequences and fused with acquisitions after contrast medium injection. Reproducibility (interclass correlation coefficients [ICCs]) of diameter and volume measurements was estimated. VM size variations in diameter and volume after sclerotherapy and contrast enhancement before sclerotherapy were compared in patients with clinical success or failure. Inter-observer ICCs were similar for diameter and volume measurements at baseline and follow-up (range 0.87-0.99). Higher percentages of size reduction after sclerotherapy were observed with volume (32.6 ± 30.7 %) than with diameter measurements (14.4 ± 21.4 %; P = 0.037). Contrast enhancement values were estimated at 65.3 ± 27.5 % and 84 ± 13 % in patients with clinical failure and success respectively (P = 0.056). Venous malformation volume was as reproducible as diameter measurement and more sensitive in detecting therapeutic responses. Patients with better clinical outcome tend to have stronger malformation enhancement. (orig.)

  1. Gadobutrol for contrast-enhanced magnetic resonance imaging in elderly patients: review of the safety profile from clinical trial, post-marketing surveillance, and pharmacovigilance data.

    Science.gov (United States)

    Endrikat, J; Schwenke, C; Prince, M R

    2015-07-01

    To assess the safety of gadobutrol administration in elderly patients (≥65 years) by comparing the incidence of adverse drug reactions (ADRs) following gadobutrol-enhanced magnetic resonance imaging (MRI) procedures in elderly patients with that in adults aged 18-64 years. Safety data on gadobutrol administration from clinical trials, post-marketing surveillance (PMS) studies, and pharmacovigilance reports were collected in three databases. In each dataset, absolute and relative frequencies of ADRs between age groups were analysed, along with odds ratios and 95% confidence intervals. Logistic regression was used to identify significant influencing factors on ADRs in the PMS and pharmacovigilance data. Rates of reported ADRs were lower in elderly patients versus adults aged statistically significant for the clinical trials and pharmacovigilance populations, with a trend in the PMS database. Serious ADRs occurred infrequently in the clinical trials and PMS populations (too low for statistical comparison), and pharmacovigilance data demonstrated a low incidence (<0.005%) in both age groups. This evaluation involving three large databases demonstrated no greater incidence of ADRs following gadobutrol-enhanced MRI in elderly patients (≥65 years) compared with younger adults, with gadobutrol having a favourable safety profile in both age groups. Copyright © 2015 The Royal College of Radiologists. All rights reserved.

  2. Audit of a policy of magnetic resonance imaging with diffusion-weighted imaging as first-line neuroimaging for in-patients with clinically suspected acute stroke

    Energy Technology Data Exchange (ETDEWEB)

    Buckley, B.T.; Wainwright, A.; Meagher, T.; Briley, D

    2003-03-01

    AIM: To audit the feasibility and use of diffusion-weighted (DW) magnetic resonance imaging (MRI) as initial neuroimaging for in-patients with clinically suspected acute stroke. MATERIALS AND METHODS: In April 2000, MRI with DW and T2-weighted sequence was locally instituted as initial neuroimaging for patients with clinically suspected acute stroke. This retrospective study reviewed imaging performed for in-patients with suspected acute stroke over a 9-month period. Data were collected on image type, result and need for repeat imaging. RESULTS: During the study period, 124 patients had neuroimaging for suspected cerebrovascular accident, and 119 were MRI safe. Eighty-eight (73.9%) patients underwent DW MRI as first-line investigation. Five patients were not MRI safe and 31 had computed tomography (CT) as first-line imaging due to lack of available MRI capacity. Repeat neuroimaging was performed in 16 (12.9%) patients. Study times were comparable for both types of neuroimaging: a mean of 13 min for MRI and 11 min for CT. CONCLUSION: The audit standard was achieved in 88 (73.9%) patients. The use of DW MRI as a first-line investigation for patients with a clinical diagnosis of acute stroke is achievable in a district general hospital setting.

  3. Magnetic Resonance Imaging of Liver Metastasis.

    Science.gov (United States)

    Karaosmanoglu, Ali Devrim; Onur, Mehmet Ruhi; Ozmen, Mustafa Nasuh; Akata, Deniz; Karcaaltincaba, Musturay

    2016-12-01

    Liver magnetic resonance imaging (MRI) is becoming the gold standard in liver metastasis detection and treatment response assessment. The most sensitive magnetic resonance sequences are diffusion-weighted images and hepatobiliary phase images after Gd-EOB-DTPA. Peripheral ring enhancement, diffusion restriction, and hypointensity on hepatobiliary phase images are hallmarks of liver metastases. In patients with normal ultrasonography, computed tomography (CT), and positron emission tomography (PET)-CT findings and high clinical suspicion of metastasis, MRI should be performed for diagnosis of unseen metastasis. In melanoma, colon cancer, and neuroendocrine tumor metastases, MRI allows confident diagnosis of treatment-related changes in liver and enables differential diagnosis from primary liver tumors. Focal nodular hyperplasia-like nodules in patients who received platinum-based chemotherapy, hypersteatosis, and focal fat can mimic metastasis. In cancer patients with fatty liver, MRI should be preferred to CT. Although the first-line imaging for metastases is CT, MRI can be used as a problem-solving method. MRI may be used as the first-line method in patients who would undergo curative surgery or metastatectomy. Current limitation of MRI is low sensitivity for metastasis smaller than 3mm. MRI fingerprinting, glucoCEST MRI, and PET-MRI may allow simpler and more sensitive diagnosis of liver metastasis. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Reducing Field Distortion in Magnetic Resonance Imaging

    Science.gov (United States)

    Eom, Byeong Ho; Penanen, Konstantin; Hahn, Inseob

    2010-01-01

    A concept for a magnetic resonance imaging (MRI) system that would utilize a relatively weak magnetic field provides for several design features that differ significantly from the corresponding features of conventional MRI systems. Notable among these features are a magnetic-field configuration that reduces (relative to the conventional configuration) distortion and blurring of the image, the use of a superconducting quantum interference device (SQUID) magnetometer as the detector, and an imaging procedure suited for the unconventional field configuration and sensor. In a typical application of MRI, a radio-frequency pulse is used to excite precession of the magnetic moments of protons in an applied magnetic field, and the decaying precession is detected for a short time following the pulse. The precession occurs at a resonance frequency proportional to the strengths of the magnetic field and the proton magnetic moment. The magnetic field is configured to vary with position in a known way; hence, by virtue of the aforesaid proportionality, the resonance frequency varies with position in a known way. In other words, position is encoded as resonance frequency. MRI using magnetic fields weaker than those of conventional MRI offers several advantages, including cheaper and smaller equipment, greater compatibility with metallic objects, and higher image quality because of low susceptibility distortion and enhanced spin-lattice-relaxation- time contrast. SQUID MRI is being developed into a practical MRI method for applied magnetic flux densities of the order of only 100 T

  5. Your Radiologist Explains Magnetic Resonance Angiography (MRA)

    Medline Plus

    Full Text Available ... Disorders Video: The Basketball Game: An MRI Story Radiology and You Sponsored by Image/Video Gallery Your ... Explains Magnetic Resonance Angiography (MRA) Transcript Welcome to Radiology Info dot org Hello, I’m Dr. Elliot ...

  6. Fifty years of nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Martinez Valderrama, Juan Crisostomo

    1997-01-01

    Short information about the main developments of nuclear magnetic resonance during their fifty existence years is presented. Beside two examples of application (HETCOR and INADEQUATE) to the structural determination of organic compounds are described

  7. Principles of nuclear magnetic resonance imaging

    International Nuclear Information System (INIS)

    Pykett, I.L.; Newhouse, J.H.; Buonanno, F.S.; Brady, T.J.; Goldman, M.R.; Kistler, J.P.; Pohost, G.M.

    1982-01-01

    The physical principles which underlie the phenomenon of nuclear magnetic resonance (NMR) are presented in this primer. The major scanning methods are reviewed, and the principles of technique are discussed. A glossary of NMR terms is included

  8. Your Radiologist Explains Magnetic Resonance Angiography (MRA)

    Medline Plus

    Full Text Available ... with you about magnetic resonance angiography, or as it’s commonly known, MRA. MRA is a noninvasive test ... of the major blood vessels throughout your body. It may be performed with or without contrast material ...

  9. The role of magnetic resonance cholangiopancreatography and ...

    African Journals Online (AJOL)

    ) is accepted as the gold standard, there is a place for magnetic resonance cholangiopancreatography (MRCP) and diffusion-weighted imaging (DWI) in the diagnosis of obstructive biliary disorders. Aim: To compare the findings of MRCP with ...

  10. Your Radiologist Explains Magnetic Resonance Angiography (MRA)

    Medline Plus

    Full Text Available ... An MRI Story Radiology and You Sponsored by Image/Video Gallery Your Radiologist Explains Magnetic Resonance Angiography ( ... posted: How to Obtain and Share Your Medical Images Movement Disorders Video: The Basketball Game: An MRI ...

  11. Your Radiologist Explains Magnetic Resonance Angiography (MRA)

    Medline Plus

    Full Text Available ... mild sedative prior to the examination. For more information about Magnetic Resonance Angiography of MRA or any ... Inc. (RSNA). To help ensure current and accurate information, we do not permit copying but encourage linking ...

  12. Chronic liver disease: evaluation by magnetic resonance

    International Nuclear Information System (INIS)

    Stark, D.D.; Goldberg, H.I.; Moss, A.A.; Bass, N.M.

    1984-01-01

    Magnetic resonance (MR) imaging distinguished hepatitis from fatty liver and cirrhosis in a woman with a history of alcohol abuse. Anatomic and physiologic manifestations of portal hypertension were also demonstrated by MR

  13. Nuclear Magnetic Resonance Trackbed Moisture Sensor System

    Science.gov (United States)

    2018-02-01

    In this initial phase, conducted from March 2015 through December 2016, Vista Clara and its subcontractor Zetica Rail successfully developed and tested a man-portable, non-invasive spot-check nuclear magnetic resonance (NMR) moisture sensor that dire...

  14. Nuclear magnetic resonance spectroscopy and imaging

    International Nuclear Information System (INIS)

    Jiang Weiping; Wang Qi; Zhou Xin

    2013-01-01

    This paper briefly introduces the basic principle of nuclear magnetic resonance (NMR). Protein's structures and functions and dynamics studied by liquid NMR are elaborated; methods for enhancing the resolution of solid state NMR and its applications are discussed; the principle of magnetic resonance imaging (MRI) is interpreted, and applications in different aspects are reviewed. Finally, the progress of NMR is commented. (authors)

  15. Concepts and indications of abdominal magnetic resonance

    International Nuclear Information System (INIS)

    Murillo Viera, Wendy

    2012-01-01

    A literature review and conceptualization was performed of the main indications of magnetic resonance studies of the abdomen and the characteristic findings for each sequence, according to organ and pathology. The radiologist has had in mind main indications for magnetic resonance studies of the abdomen, with the purpose to guide the clinician in the choice of imaging modality that works best for the patient at diagnosis [es

  16. Magnetic resonance imaging of muscle tears

    International Nuclear Information System (INIS)

    De Smet, A.A.; Fisher, D.R.; Heiner, J.P.; Keene, J.S.

    1990-01-01

    Magnetic resonance scans were obtained on 17 patients with acute, subacute, or chronic muscle tears. These patients presented with complaints of persistent pain or a palpable mass. Magnetic resonance findings were characterized according to alterations in muscle shape and the presence of abnormal high signal within the injured muscle. These areas of high signal were noted on both T1-weighted and T2-weighted scans and were presumed to represent areas of intramuscular hemorrhage. (orig.)

  17. Characterization of human breast disease using phosphorus magnetic resonance spectroscopy and proton magnetic resonance imaging

    International Nuclear Information System (INIS)

    Merchant, T.E.

    1992-01-01

    This thesis provides the fundamental characterization and differentiation of breast tissues using in vivo and ex vivo MR techniques in the hope that these techniques and experimental findings will be used on a larger scale and in a predictive manner in order to improve the specificity of diagnosis and treatment of breast cancer. In this dissertation, clinical studies were performed using proton magnetic resonance imaging and phosphorus magnetic resonance spectro-scopy ( 31 P MRS) to characterize and differentiate malignant breast tumors, benign breast tumors and normal breast tissues in vivo. These studies were carried out following the methodical characterization of chemical extracts of malignant breast tumor, benign breast tumor and normal breast parenchymal surgical tissue specimens using high resolution 31 P MRS. Alterations in breast tissue metabolism, as a result of pathological processes, were postulated to be responsible for measurable differences between malignant breast tumors, benign breast tumors and normal breast tissues using magnetic resonance techniques. (author). 365 refs.; 37 figs.; 25 tabs

  18. Nuclear magnetic resonance method and apparatus

    International Nuclear Information System (INIS)

    Burl, M.; Young, I.R.

    1984-01-01

    A method and apparatus for determining the rate of flow of a liquid in a selected region of a body by nuclear magnetic resonance techniques are described. The method includes a sequence of applying a first magnetic pulse effective to excite nuclear magnetic resonance of a chosen nucleus within the liquid preferentially in a slice of the body which includes the selected region. A period of time (tsub(D)) is waited and then a second magnetic pulse is applied which is effective to excite nuclear magnetic resonance of the nuclei preferentially in the slice, and the free induction decay signal is measured. The whole sequence is repeated for different values of the period of time (tsub(D)). The variation in the value of the measured signal with tsub(D) is then related to the rate of flow of the liquid through the slice. (author)

  19. Parenchymal abnormalities in cerebral venous thrombosis: findings of magnetic resonance imaging and magnetic resonance angiography

    International Nuclear Information System (INIS)

    Ferreira, Clecia Santos; Pellini, Marcos; Boasquevisque, Edson; Souza, Luis Alberto M. de

    2006-01-01

    Objective: to determine the frequency and localization of parenchymal abnormalities in cerebral venous thrombosis on magnetic resonance imaging and magnetic resonance angiography as well as their correlation with the territory and affected venous drainage. Materials and methods: retrospective analysis (1996 to 2004) of 21 patients (3 male and 18 female) age range between 3 and 82 years (mean 40 years, median 36 years) with clinical and radiological diagnosis of cerebral venous thrombosis on magnetic resonance imaging and magnetic resonance angiography in 2D PC, 3D PC and contrast-enhanced 3D TOF sequences. The statistical analysis was performed with the qui-square test. Four patients had follow-up exams and three patients underwent digital subtraction angiography. Results: main predisposing factors were: infection, use of oral contraceptives, hormone replacement therapy and collagenosis. Predominant symptoms included: focal deficit, headache, alteration of consciousness level and seizures. Most frequent parenchymal manifestations were: cortical/subcortical edema or infarct, venous congestion and collateral circulation, meningeal enhancement and thalamic and basal ganglia edema or infarct. Occlusion occurred mainly in superior sagittal, left transverse, left sigmoid and straight sinuses. Cavernous sinus and cortical veins thrombosis are uncommon events. Conclusion: cerebral venous thrombosis is an uncommon cause of stroke, with favorable prognosis because of its reversibility. Diagnosis is highly dependent on the radiologist capacity to recognize the presentations of this disease, principally in cases where the diagnosis is suggested by parenchymal abnormalities rather than necessarily by visualization of the thrombus itself. An accurate and rapid diagnosis allows an immediate treatment, reducing the morbidity and mortality rates. (author)

  20. Evaluation of Mayer-Rokitansky-Kuester-Hauser syndrome with magnetic resonance imaging: Three patterns of uterine remnants and related anatomical features and clinical settings

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yue; Lu, Jingjing; Jiang, Bo; Feng, Feng; Jin, Zhengyu [Peking Union Medical College, Chinese Academy of Medical Sciences, Department of Radiology, Peking Union Medical College Hospital, Beijing (China); Zhu, Lan; Sun, Zhijing [Chinese Academy of Medical Sciences, Department of Obstetrics and Gynaecology, Peking Union Medical College Hospital, Peking Union Medical College, Bejing (China)

    2017-12-15

    To characterize the anatomical features and clinical settings of Mayer-Rokitansky-Kuester-Hauser (MRKH) syndrome and correlate them with patterns of uterine involvement. Pelvic magnetic resonance images and medical records of 92 MRKH patients were retrospectively reviewed. Patients were subgrouped by uterine morphology: uterine agenesis, unilateral rudimentary uterus and bilateral rudimentary uteri. Uterine volume, presence of endometrium, location of ovary, endometriosis and pelvic pain were compared among groups. The mean uterine volume was 33.5 ml (17.5-90.0 ml) for unilateral uterine remnants, and 16.1 ml (3.5-21.5 ml) for bilateral uterine rudiments (p<0.01). The incidence of presence of endometrium (100% vs. 22%, p<0.001), haematometra (56% vs. 3%, p<0.001) and ovarian endometriosis (22% vs. 3%, p<0.01) was significantly increased in the group of unilateral rudimentary uteri as compared with the group of bilateral uterine remnants. Thirty-one patients (38%) showed ectopic ovaries. Pelvic pain was more common in individuals with unilateral rudimentary uterus than those who had no (56% vs. 5%, p<0.01) or bilateral uterine remnants (56% vs. 14%, p<0.05). MRKH patients with different patterns of uterine involvement may have differentiated anatomical features and clinical settings. (orig.)

  1. Clinical application of bilateral high temporal and spatial resolution dynamic contrast-enhanced magnetic resonance imaging of the breast at 7 T

    Energy Technology Data Exchange (ETDEWEB)

    Pinker, K.; Baltzer, P.; Bernathova, M.; Weber, M.; Leithner, D.; Helbich, T.H. [Medical University Vienna, Department of Biomedical Imaging and Image-guided Therapy, Division of Molecular and Gender Imaging, Waehringer Guertel 18-20, 1090, Vienna (Austria); Bogner, W.; Trattnig, S.; Gruber, S.; Zaric, O. [Medical University Vienna, Department of Biomedical Imaging and Image-guided Therapy, MR Centre of Excellence, Vienna (Austria); Abeyakoon, O. [King' s College, Department of Radiology, London (United Kingdom); Dubsky, P. [Medical University Vienna, Department of Surgery, Vienna (Austria); Bago-Horvath, Z. [Medical University Vienna, Department of Pathology, Vienna (Austria)

    2014-04-15

    The objective of our study was to evaluate the clinical application of bilateral high spatial and temporal resolution dynamic contrast-enhanced magnetic resonance imaging (HR DCE-MRI) of the breast at 7 T. Following institutional review board approval 23 patients with a breast lesion (BIRADS 0, 4-5) were included in our prospective study. All patients underwent bilateral HR DCE-MRI of the breast at 7 T (spatial resolution of 0.7 mm{sup 3} voxel size, temporal resolution of 14 s). Two experienced readers (r1, r2) and one less experienced reader (r3) independently assessed lesions according to BI-RADS registered. Image quality, lesion conspicuity and artefacts were graded from 1 to 5. Sensitivity, specificity and diagnostic accuracy were assessed using histopathology as the standard of reference. HR DCE-MRI at 7 T revealed 29 lesions in 23 patients (sensitivity 100 % (19/19); specificity of 90 % (9/10)) resulting in a diagnostic accuracy of 96.6 % (28/29) with an AUC of 0.95. Overall image quality was excellent in the majority of cases (27/29) and examinations were not hampered by artefacts. There was excellent inter-reader agreement for diagnosis and image quality parameters (κ = 0.89-1). Bilateral HR DCE-MRI of the breast at 7 T is feasible with excellent image quality in clinical practice and allows accurate breast cancer diagnosis. (orig.)

  2. Clinical significance of cerebrospinal fluid tap test and magnetic resonance imaging/computed tomography findings of tight high convexity in patients with possible idiopathic normal pressure hydrocephalus

    International Nuclear Information System (INIS)

    Ishikawa, Masatsune; Furuse, Motomasa; Nishida, Namiko; Oowaki, Hisayuki; Matsumoto, Atsuhito; Suzuki, Takayuki

    2010-01-01

    Idiopathic normal pressure hydrocephalus (iNPH) is a treatable syndrome with a classical triad of symptoms. The Japanese iNPH guidelines indicate that the cerebrospinal fluid (CSF) tap test and tight high-convexity on magnetic resonance (MR) imaging are important for the diagnosis. The relationships between the effectiveness of CSF shunt surgery in possible iNPH patients, the tap test result, and the MR imaging/computed tomography (CT) findings of tight high-convexity were evaluated in 88 possible iNPH patients (mean age 75 years) with one or more of the classical triad of symptoms, and mild to moderate ventricular dilation. All patients underwent the tap test in the outpatient clinic, and patients and caregivers assessed the clinical changes during one week. The tap test was positive in 47 patients and negative in 41 patients. Surgery was performed in 19 patients with positive tap test, and was effective in 17 patients. Although the findings were inconsistent in some patients, the result of the tap test was found to be highly correlated with the MR imaging/CT finding of tight high-convexity (p<0.0001), confirming that both these diagnostic tests are promising predictors of shunt effectiveness. (author)

  3. Measurement of blood flow in the left ventricle and aorta using clinical 2D cine phase-contrast magnetic resonance imaging

    International Nuclear Information System (INIS)

    Nakamura, Masanori; Wada, Shigeo; Yokosawa, Suguru; Yamaguchi, Takami; Isoda, Haruo; Takeda, Hiroyasu

    2007-01-01

    A recent development in phase-contrast magnetic resonance imaging (cine PC-MRI) allows the detailed measurement of the blood flow in humans. The objectives of this study are twofold: to discuss the utility of clinical two-dimensional (2D) cine PC-MRI as a practical tool for analyzing hemodynamics in the aorta and left ventricle; to provide flow information at those places as references for computational fluid dynamics studies. Using 2D cine PC-MRI, we mapped velocity profiles at various cross sections of the aorta and left ventricle. The results illustrated the main flow events in the left ventricle during the cardiac cycle, such as ventricular ejection and suction, while the secondary flows were less clear. The velocity profile at the entrance of the ascending aorta appeared to be slightly skewed posteriorly in early systole, but the flow in the central zone of the section was rapid. The estimated stroke volume, peak Reynolds numbers, and Womersley numbers were within the normal physiological range. A sequence of secondary flow images from the plane of the aortic valve to the descending aorta revealed the evolution of a helical flow within the aorta. Flows entering the aortic branches were captured well. Those results demonstrate that clinical 2D cine PC-MRI is a practical adjunct for analyzing blood flow in vivo and would be useful as references to check validity of flow dynamics obtained by computer simulations. (author)

  4. Ultra high field magnetic resonance imaging

    International Nuclear Information System (INIS)

    Lethimonnier, F.; Vedrine, P.

    2007-01-01

    Understanding human brain function, brain development and brain dysfunction is one of the great challenges of the twenty first century. Biomedical imaging has now run up against a number of technical constraints that are exposing limits to its potential. In order to overcome the current limits to high-field magnetic resonance cerebral imaging (MRI) and unleash its fullest potential, the Cea has built NeuroSpin, an ultra-high-field neuroimaging facility at its Saclay centre (in the Essonne). NeuroSpin already boasts three fully operational MRI systems. The first is a 3-tesla high-field system and the second is a very-high-field 7-tesla system, both of which are dedicated to clinical studies and investigations in humans, while the third is an ultra-high-field 17.65-tesla system designed for studies on small animals. In 2011, NeuroSpin will be commissioning an 11.7-tesla ultra-high-field system of unprecedented power that is designed for research on human subjects. The level of the magnetic field and the scale required will make this joint French-German project to build the magnet a breakthrough in the international arena. (authors)

  5. Resonance double magnetic bremsstrahlung in a strong magnetic field

    International Nuclear Information System (INIS)

    Fomin, P.I.; Kholodov, R.I.

    2003-01-01

    The possibility of resonance double magnetic bremsstrahlung in the approximation of weakly excited electron states in a strong external magnetic field is analyzed. The differential probability of this process in the Breit-Wigner form is obtained. The probability of double magnetic bremsstrahlung (second-order process of perturbation theory) is compared with the probability of magnetic bremsstrahlung (first-order process of perturbation theory)

  6. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... a powerful magnetic field, radio waves and a computer to produce detailed pictures of the brain and ... powerful magnetic field, radio frequency pulses and a computer to produce detailed pictures of organs, soft tissues, ...

  7. Children's (Pediatric) Magnetic Resonance Imaging

    Medline Plus

    Full Text Available ... a powerful magnetic field, radio waves and a computer to produce detailed pictures of the inside of ... powerful magnetic field, radio frequency pulses and a computer to produce detailed pictures of organs, soft tissues, ...

  8. Children's (Pediatric) Magnetic Resonance Imaging

    Medline Plus

    Full Text Available ... help detect certain chronic diseases of the nervous system, such as multiple sclerosis diagnose problems with the ... the magnet. Some MRI units, called short-bore systems , are designed so that the magnet does not ...

  9. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    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 ...

  10. Children's (Pediatric) Magnetic Resonance Imaging

    Medline Plus

    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. Your child will lie on a moveable examination ...

  11. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    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 ...

  12. Magnetic resonance arthrography in chronic wrist pain

    International Nuclear Information System (INIS)

    Valeri, G.; Ferrara, C.; Carloni, S.

    1999-01-01

    The purpose of this paper is to investigate the clinical role of Magnetic Resonance Arthrography (MRA) of the wrist in subjects with chronic pain. Thirty-five patients complaining of wrist pain for more than 6 months were submitted to MRI an MRA. All patients received and intra-articular injection of 2-10 mL of a 10 mmol saline solution of Gd-DPTA. The overall diagnostic accuracy rates of MRI and MRA were 40% and 81% respectively, with sensitivity and specificity of 63% and 39% (MRI) and of 82% and 79% (MRA). The conclusion is that compared with MRI, MRA can be considered a useful tool for the visualization of interosseus carpal ligaments and of the triangular fibrocartilage complex. MRA also helps detect injuries in these structures [it

  13. Cardiovascular magnetic resonance in carotid atherosclerotic disease

    Directory of Open Access Journals (Sweden)

    Chen Huijun

    2009-12-01

    Full Text Available Abstract Atherosclerosis is a chronic, progressive, inflammatory disease affecting many vascular beds. Disease progression leads to acute cardiovascular events such as myocardial infarction, stroke and death. The diseased carotid alone is responsible for one third of the 700,000 new or recurrent strokes occurring yearly in the United States. Imaging plays an important role in the management of atherosclerosis, and cardiovascular magnetic resonance (CMR of the carotid vessel wall is one promising modality in the evaluation of patients with carotid atherosclerotic disease. Advances in carotid vessel wall CMR allow comprehensive assessment of morphology inside the wall, contributing substantial disease-specific information beyond luminal stenosis. Although carotid vessel wall CMR has not been widely used to screen for carotid atherosclerotic disease, many trials support its potential for this indication. This review summarizes the current state of knowledge regarding carotid vessel wall CMR and its potential clinical application for management of carotid atherosclerotic disease.

  14. Magnetic resonance imaging of pancreatitis: An update

    Science.gov (United States)

    Manikkavasakar, Sriluxayini; AlObaidy, Mamdoh; Busireddy, Kiran K; Ramalho, Miguel; Nilmini, Viragi; Alagiyawanna, Madhavi; Semelka, Richard C

    2014-01-01

    Magnetic resonance (MR) imaging plays an important role in the diagnosis and staging of acute and chronic pancreatitis and may represent the best imaging technique in the setting of pancreatitis due to its unmatched soft tissue contrast resolution as well as non-ionizing nature and higher safety profile of intravascular contrast media, making it particularly valuable in radiosensitive populations such as pregnant patients, and patients with recurrent pancreatitis requiring multiple follow-up examinations. Additional advantages include the ability to detect early forms of chronic pancreatitis and to better differentiate adenocarcinoma from focal chronic pancreatitis. This review addresses new trends in clinical pancreatic MR imaging emphasizing its role in imaging all types of acute and chronic pancreatitis, pancreatitis complications and other important differential diagnoses that mimic pancreatitis. PMID:25356038

  15. Magnetic resonance imaging of spinal plasmacytoma

    International Nuclear Information System (INIS)

    Shah, B.K.; Saifuddin, A.; Price, G.J.

    2000-01-01

    AIM: To describe the magnetic resonance imaging (MRI) features of spinal plasmacytoma. MATERIALS AND METHODS: The clinical records and MRI findings in six patients (five men, one woman; age range 41-61 years) with histologically proven plasmacytoma of the spine were reviewed. All studies included sagittal T1- and T2-weighted spin-echo sequences and axial T1-weighted spin-echo sequences. Intravenous gadolinium DTPA was administered in four cases. RESULTS: MRI showed a characteristic appearances in four cases of low signal intensity curvilinear areas within the vertebra or cortical irregularity. CONCLUSION: Recognition of these imaging features can initiate the appropriate investigation as the commonest differential diagnosis for such lesions is metastasis. Shah, B. K. (2000)

  16. Magnetic resonance imaging of hypothalamic hamartoma

    Energy Technology Data Exchange (ETDEWEB)

    Kanazawa, Junichi; Uozumi, Tohru; Sakoda, Katsuaki; Yamanaka, Masami; Kihara, Mikio; Nishi, Yoshikazu; Kagawa, Yoshihiro; Kajima, Toshio.

    1988-05-01

    Magnetic resonance (MR) findings of two patients with a hypothalamic hamartoma are discussed. The two girls showed clinical symptoms and endocrinological signs of precocious puberty. MR imaging was of diagnostic value superior to that of CT in the demonstration of the characteristic location of this tumor and relationships to the neighboring structures because of its multi-dimensional utility. Although it has been reported that CT showed this lesion as isodense to the grey matter with and without injection of contrast medium, MR imaging depicted the lesion as a high signal intensity area on T2-weighted images in both patients. MR imaging is a useful method for the evaluation of the hypothalamic hamartoma.

  17. Pharmaceutical applications of magnetic resonance imaging (MRI).

    Science.gov (United States)

    Richardson, J Craig; Bowtell, Richard W; Mäder, Karsten; Melia, Colin D

    2005-06-15

    Magnetic resonance imaging (MRI) is a powerful imaging modality that provides internal images of materials and living organisms on a microscopic and macroscopic scale. It is non-invasive and non-destructive, and one of very few techniques that can observe internal events inside undisturbed specimens in situ. It is versatile, as a wide range of NMR modalities can be accessed, and 2D and 3D imaging can be undertaken. Despite widespread use and major advances in clinical MRI, it has seen limited application in the pharmaceutical sciences. In vitro studies have focussed on drug release mechanisms in polymeric delivery systems, but isolated studies of bioadhesion, tablet properties, and extrusion and mixing processes illustrate the wider potential. Perhaps the greatest potential however, lies in investigations of pharmaceuticals in vivo, where pilot human and animal studies have demonstrated we can obtain unique insights into the behaviour of gastrointestinal, topical, colloidal, and targeted drug delivery systems.

  18. Cardiovascular magnetic resonance in pulmonary hypertension

    Science.gov (United States)

    2012-01-01

    Pulmonary hypertension represents a group of conditions characterized by higher than normal pulmonary artery pressures. Despite improved treatments, outcomes in many instances remain poor. In recent years, there has been growing interest in the use of Cardiovascular Magnetic Resonance (CMR) in patients with pulmonary hypertension. This technique offers certain advantages over other imaging modalities since it is well suited to the assessment of the right ventricle and the proximal pulmonary arteries. Reflecting the relatively sparse evidence supporting its use, CMR is not routinely recommended for patients with pulmonary hypertension. However, it is particularly useful in patient with pulmonary arterial hypertension associated with congenital heart disease. Furthermore, it has proven informative in a number of ways; illustrating how right ventricular remodeling is favorably reversed by drug therapies and providing explicit confirmation of the importance of the right ventricle to clinical outcome. This review will discuss these aspects and practical considerations before speculating on future applications. PMID:22257586

  19. Magnetic islands created by resonant helical windings

    International Nuclear Information System (INIS)

    Fernandes, A.S.; Heller, M.V.; Caldas, I.L.

    1986-01-01

    The triggering of disruptive instabilities by resonant helical windings in large aspect-ratio tokamaks is associated to destruction of magnetic surfaces. The Chirikov condition is applied to estimate analytically the helical winding current thresholds for ergodization of the magnetic field lines. (Autor) [pt

  20. Topical questions in magnetic resonance imaging

    International Nuclear Information System (INIS)

    Andrew, E.R.; Florida Univ., Gainesville, FL; Florida Univ., Gainesville, FL

    1989-01-01

    This paper examines a number of practical questions concerning magnetic resonance imaging. These include the choice of operating magnetic field strength, the problem of siting and screening, a procedure for securing precise slice selection and the use of paramagnetic contrast agents. (author). 5 refs