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Sample records for cardiac magnetic resonance

  1. Automated Segmentation of Cardiac Magnetic Resonance Images

    DEFF Research Database (Denmark)

    Stegmann, Mikkel Bille; Nilsson, Jens Chr.; Grønning, Bjørn A.

    2001-01-01

    Magnetic resonance imaging (MRI) has been shown to be an accurate and precise technique to assess cardiac volumes and function in a non-invasive manner and is generally considered to be the current gold-standard for cardiac imaging [1]. Measurement of ventricular volumes, muscle mass and function...

  2. Cardiac Magnetic Resonance In Adults With Congenital Heart Disease

    OpenAIRE

    Partington, Sara L.; Valente, Anne Marie

    2013-01-01

    Increasing numbers of adults with congenital heart disease are referred for cardiac magnetic resonance imaging. Knowledge of the congenital heart anatomy, prior surgical interventions, and the development of an imaging focus for each individual patient plays a crucial role when performing a successful cardiac magnetic resonance imaging examination. The following manuscript focuses on cardiac magnetic resonance imaging considerations of three specific conotruncal congenital heart lesions: tetr...

  3. Cardiac magnetic resonance in clinical cardiology

    Institute of Scientific and Technical Information of China (English)

    Andreas; Kumar; Rodrigo; Bagur

    2015-01-01

    Over the last decades, cardiac magnetic resonance(CMR) has transformed from a research tool to a widely used diagnostic method in clinical cardiology. This method can now make useful, unique contributions to the work-up of patients with ischemic and non-ischemic heart disease. Advantages of CMR, compared to other imaging methods, include very high resolution imaging with a spatial resolution up to 0.5 mm × 0.5 mm in plane, a large array of different imaging sequences to provide in vivo tissue characterization, and radiationfree imaging. The present manuscript highlights the relevance of CMR in the current clinical practice and new perspectives in cardiology.

  4. Magnetic resonance imaging of congenital cardiac abnormalities

    International Nuclear Information System (INIS)

    Magnetic resonance imaging will not replace echocardiography as the simplest and most definitive method of establishing a noninvasive diagnosis in young patients with congenital cardiac malformations, nor will it replace radionuclide angiography for relatively noninvasive detection and quantitation of cardiac shunts. Magnetic resonance imaging is a complementary noninvasive imaging procedure that can answer some questions left in doubt by echocardiography (mainly extracardiac artery and vein assessments) or radionuclide angiography and used as a preferred follow-up imaging method in certain clinical circumstances. In addition, MRI can be a first-line modality for cardiovascular imaging in older patients in whom adequate echo windows are not available. Angiocardiography remains necessary to provide vital physiological data, i.e., chamber pressures, shunt volumes, oxygen saturations, and pulmonary vascular resistance; however, MRI could negate some follow-up catheterizations in appropriate clinical circumstances. High-resolution proton MRI tomography should ultimately permit the accurate evaluation of ventricular volumes, myocardial mass, and the assessment of regional wall motion and ejection fractions. Paramagnetic substances such as manganese ion may ultimately provide a basis for myocardial perfusion imaging. The potential for MRI evaluation of tissue characterization, noninvasive blood-flow measurements, and myocardial metabolism assessment in intriguing and awaits clinical evaluation

  5. Italian registry of cardiac magnetic resonance

    International Nuclear Information System (INIS)

    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

  6. 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.

  7. Magnetic Resonance Imaging of Benign Cardiac Masses: A Pictorial Essay

    Directory of Open Access Journals (Sweden)

    Thomas J Ward

    2013-01-01

    Full Text Available The differential diagnosis for a cardiac mass includes primary and metastatic neoplasms. While primary cardiac tumors are rare, metastatic disease to the heart is a common finding in cancer patients. Several "tumor-like" processes can mimic a true cardiac neoplasm with accurate diagnosis critical at guiding appropriate management. We present a pictorial essay of the most common benign cardiac masses and "mass-like" lesions with an emphasis on magnetic resonance imaging features.

  8. Advances in cardiac magnetic resonance imaging of congenital heart disease

    International Nuclear Information System (INIS)

    Due to advances in cardiac surgery, survival of patients with congenital heart disease has increased considerably during the past decades. Many of these patients require repeated cardiovascular magnetic resonance imaging to assess cardiac anatomy and function. In the past decade, technological advances have enabled faster and more robust cardiovascular magnetic resonance with improved image quality and spatial as well as temporal resolution. This review aims to provide an overview of advances in cardiovascular magnetic resonance hardware and acquisition techniques relevant to both pediatric and adult patients with congenital heart disease and discusses the techniques used to assess function, anatomy, flow and tissue characterization. (orig.)

  9. Advances in cardiac magnetic resonance imaging of congenital heart disease.

    Science.gov (United States)

    Driessen, Mieke M P; Breur, Johannes M P J; Budde, Ricardo P J; van Oorschot, Joep W M; van Kimmenade, Roland R J; Sieswerda, Gertjan Tj; Meijboom, Folkert J; Leiner, Tim

    2015-01-01

    Due to advances in cardiac surgery, survival of patients with congenital heart disease has increased considerably during the past decades. Many of these patients require repeated cardiovascular magnetic resonance imaging to assess cardiac anatomy and function. In the past decade, technological advances have enabled faster and more robust cardiovascular magnetic resonance with improved image quality and spatial as well as temporal resolution. This review aims to provide an overview of advances in cardiovascular magnetic resonance hardware and acquisition techniques relevant to both pediatric and adult patients with congenital heart disease and discusses the techniques used to assess function, anatomy, flow and tissue characterization. PMID:25552386

  10. Advances in cardiac magnetic resonance imaging of congenital heart disease

    Energy Technology Data Exchange (ETDEWEB)

    Driessen, Mieke M.P. [University of Utrecht, University Medical Center Utrecht, Department of Radiology, PO Box 85500, Utrecht (Netherlands); University of Utrecht, University Medical Center Utrecht, Department of Cardiology, PO Box 85500, Utrecht (Netherlands); The Interuniversity Cardiology Institute of the Netherlands (ICIN) - Netherlands Heart Institute, PO Box 19258, Utrecht (Netherlands); Breur, Johannes M.P.J. [Wilhelmina Children' s Hospital, University Medical Center Utrecht, Department of Pediatric Cardiology, PO Box 85500, Utrecht (Netherlands); Budde, Ricardo P.J.; Oorschot, Joep W.M. van; Leiner, Tim [University of Utrecht, University Medical Center Utrecht, Department of Radiology, PO Box 85500, Utrecht (Netherlands); Kimmenade, Roland R.J. van; Sieswerda, Gertjan Tj [University of Utrecht, University Medical Center Utrecht, Department of Cardiology, PO Box 85500, Utrecht (Netherlands); Meijboom, Folkert J. [University of Utrecht, University Medical Center Utrecht, Department of Cardiology, PO Box 85500, Utrecht (Netherlands); Wilhelmina Children' s Hospital, University Medical Center Utrecht, Department of Pediatric Cardiology, PO Box 85500, Utrecht (Netherlands)

    2015-01-01

    Due to advances in cardiac surgery, survival of patients with congenital heart disease has increased considerably during the past decades. Many of these patients require repeated cardiovascular magnetic resonance imaging to assess cardiac anatomy and function. In the past decade, technological advances have enabled faster and more robust cardiovascular magnetic resonance with improved image quality and spatial as well as temporal resolution. This review aims to provide an overview of advances in cardiovascular magnetic resonance hardware and acquisition techniques relevant to both pediatric and adult patients with congenital heart disease and discusses the techniques used to assess function, anatomy, flow and tissue characterization. (orig.)

  11. Advances in cardiac magnetic resonance imaging of congenital heart disease

    NARCIS (Netherlands)

    Driessen, Mieke M P; Breur, Johannes M. P. J.; Budde, Ricardo P J; van Oorschot, Joep W M; van Kimmenade, Roland R J; Sieswerda, Gertjan Tj.; Meijboom, Folkert J; Leiner, Tim

    2015-01-01

    Due to advances in cardiac surgery, survival of patients with congenital heart disease has increased considerably during the past decades. Many of these patients require repeated cardiovascular magnetic resonance imaging to assess cardiac anatomy and function. In the past decade, technological advan

  12. Magnetic resonance imaging in the evaluation of congestive cardiac failure

    OpenAIRE

    Rajiah, Prabhakar

    2012-01-01

    Congestive cardiac failure is the end-result of various cardiac disorders, and is a major contributor to morbidity, mortality, and financial burden throughout the world. Due to advances in the knowledge of the disease and scanner technology, magnetic resonance imaging (MRI) is playing an increasingly important role in the evaluation of cardiac failure, including in establishing diagnosis, problem solving, risk stratification, and monitoring of therapy. This review discusses and illustrates th...

  13. Cardiac magnetic resonance imaging of a patient with an magnetic resonance imaging conditional permanent pacemaker

    OpenAIRE

    Chris B. Pepper; Mohan Sivananthan; Artis, Nigel J.; Hogarth, Andrew J.

    2011-01-01

    Cardiac Magnetic Resonance Imaging (MRI) is increasingly used as the optimum modality for cardiac imaging. An aging population and rising numbers of patients with permanent pacemakers means many such individuals may require cardiac MRI scanning in the future. Whilst the presence of a permanent pacemaker is historically regarded as a contra-indication to MRI scanning, pacemaker systems have been developed to limit any associated risks. No reports have been published regarding the use of such d...

  14. Intraocular lymphoma after cardiac transplantation: Magnetic resonance imaging findings

    International Nuclear Information System (INIS)

    We report a case of intraocular lymphoma in a 65-year-old man, 15 months after cardiac transplantation. On Magnetic Resonance (MR) images, the iris and the anterior chamber of the right eye were found to be involved with an enhancing soft-tissue lesion. To our knowledge, this is the first case of post-transplantation intraocular lymphoma evaluated with MR imaging.

  15. Intraocular lymphoma after cardiac transplantation: Magnetic resonance imaging findings

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yi Kyung; Kim, Hyung Jin; Woo, Kyung In; Kim, Yoon Duck [Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2013-01-15

    We report a case of intraocular lymphoma in a 65-year-old man, 15 months after cardiac transplantation. On Magnetic Resonance (MR) images, the iris and the anterior chamber of the right eye were found to be involved with an enhancing soft-tissue lesion. To our knowledge, this is the first case of post-transplantation intraocular lymphoma evaluated with MR imaging.

  16. Unveiling nonischemic cardiomyopathies with cardiac magnetic resonance.

    Science.gov (United States)

    Aggarwal, Niti R; Peterson, Tyler J; Young, Phillip M; Araoz, Philip A; Glockner, James; Mankad, Sunil V; Williamson, Eric E

    2014-02-01

    Cardiomyopathy is defined as a heterogeneous group of myocardial disorders with mechanical or electrical dysfunction. Identification of the etiology is important for accurate diagnosis, treatment and prognosis, but continues to be challenging. The ability of cardiac MRI to non-invasively obtain 3D-images of unparalleled resolution without radiation exposure and to provide tissue characterization gives it a distinct advantage over any other diagnostic tool used for evaluation of cardiomyopathies. Cardiac MRI can accurately visualize cardiac morphology and function and also help identify myocardial edema, infiltration and fibrosis. It has emerged as an important diagnostic and prognostic tool in tertiary care centers for work up of patients with non-ischemic cardiomyopathies. This review covers the role of cardiac MRI in evaluation of nonischemic cardiomyopathies, particularly in the context of other diagnostic and prognostic imaging modalities. PMID:24417294

  17. Cardiac magnetic resonance imaging in Alström syndrome

    Directory of Open Access Journals (Sweden)

    Carey Catherine M

    2009-06-01

    Full Text Available Abstract Background A case series of the cardiac magnetic resonance imaging findings in seven adult Alström patients. Methods Seven patients from the National Specialist Commissioning Group Centre for Alström Disease, Torbay, England, UK, completed the cardiac magnetic resonance imaging protocol to assess cardiac structure and function in Alström cardiomyopathy. Results All patients had some degree of left and right ventricular dysfunction. Patchy mid wall gadolinium delayed enhancement was demonstrated, suggesting an underlying fibrotic process. Some degree of cardiomyopathy was universal. No evidence of myocardial infarction or fatty infiltration was demonstrated, but coronary artery disease cannot be completely excluded. Repeat scanning after 18 months in one subject showed progression of fibrosis and decreased left ventricular function. Conclusion Adult Alström cardiomyopathy appears to be a fibrotic process causing impairment of both ventricles. Serial cardiac magnetic resonance scanning has helped clarify the underlying disease progression and responses to treatment. Confirmation of significant mutations in the ALMS1 gene should lead to advice to screen the subject for cardiomyopathy, and metabolic disorders.

  18. Cardiac sarcoidosis &hypen; the value of magnetic resonance imaging.

    Science.gov (United States)

    Smedema, J. P.; Doubell, A. F.

    2000-08-01

    This report describes the management of a 40-year-old woman presenting with recurrent monomorphic ventricular tachycardias secondary to cardiac sarcoidosis. She was managed with a combination of steroids, azathioprine and mexiletine. Magnetic resonance imaging proved to be of great help in diagnosing this condition as well as in following up the response to therapy. A brief review on the management of this condition is presented. PMID:11447482

  19. Giant right atrial myxoma: characterization with cardiac magnetic resonance imaging.

    LENUS (Irish Health Repository)

    Ridge, Carole A

    2012-02-01

    A 53-year-old woman presented to the emergency department with a 2-week history of dyspnoea and chest pain. Computed tomography pulmonary angiography was performed to exclude acute pulmonary embolism (PE). This demonstrated a large right atrial mass and no evidence of PE. Transthoracic echocardiography followed by cardiac magnetic resonance imaging confirmed a mobile right atrial mass. Surgical resection was then performed confirming a giant right atrial myxoma. We describe the typical clinical, radiologic, and pathologic features of right atrial myxoma.

  20. Cardiac magnetic resonance spectroscopy: potential clinical applications

    International Nuclear Information System (INIS)

    MR spectroscopy is the only method for non-invasive detection of various aspects of cardiac metabolism in humans. While the 1H nucleus of water and fat molecules is the signal source for MR imaging, the MR spectroscopic technique allows for the study of a number of other nuclei, such as 13C, 19F, 23Na, 31P, 39K and 87Rb. Clinical applications presently are confined to the 31P nucleus. 31P-MR spectroscopy allows the non-invasive study of cardiac high-energy phosphate metabolites ATP and phosphocreatine. The phosphocreatine/ATP ratio is considered an index of the energetic state of the heart. Possible clinical indications include heart failure, valve disease and coronary artery disease. In heart failure, the phosphocreatine/ATP ratio is reduced and correlates with clinical severity, ejection fraction and prognosis. In mitral and aortic valve disease, a reduced phosphocreatine/ATP ratio may indicate the optimum timing for valve replacement. In coronary artery disease, a regional decrease of phosphocreatine during stress (''biochemical ergometry'') may indicate local ischemia. Furthermore, absolute quantification of high-energy phosphates may allow diagnosis of myocardial viability. Major technical developments, leading to improved spatial and temporal resolution will be necessary to establish MR spectroscopy as a routine clinical tool. (orig.)

  1. Cardiac carcinoid: tricuspid delayed hyperenhancement on cardiac 64-slice multidetector CT and magnetic resonance imaging.

    LENUS (Irish Health Repository)

    Martos, R

    2012-02-01

    INTRODUCTION: Carcinoid heart disease is a rare condition in adults. Its diagnosis can be easily missed in a patient presenting to a primary care setting. We revised the advantages of using coronary multidetector computed tomography (MDCT) and cardiac magnetic resonance imaging (MRI) in diagnosing this condition. MATERIALS AND METHODS: We studied a 65-year-old patient with carcinoid heart disease and right heart failure using transthoracic Doppler-echocardiogram, cardiac MDCT and MRI. Cardiac echocardiogram revealed marked thickening and retraction of the tricuspid leaflets with dilated right atrium and ventricle. Cardiac MDCT and MRI demonstrated fixation and retraction of the tricuspid leaflets with delayed contrast hyperenhancement of the tricuspid annulus. CONCLUSION: This case demonstrates fascinating imaging findings of cardiac carcinoid disease and highlights the increasing utility of contrast-enhanced MRI and cardiac MDCT in the diagnosis of this interesting condition.

  2. ABC of the cardiac magnetic resonance. Part 1: perfusion, viability and coronary anatomy

    International Nuclear Information System (INIS)

    The objective of this work is to demonstrate the fundamental concepts, the basic sequences and the clinical and potential applications of cardiac magnetic resonance as a diagnostic technique in updated radiology and cardiology practices. In this second part, we present basic aspects of the cardiac magnetic resonance application in the coronary anatomy and myocardial perfusion and viability. (author)

  3. Acupuncture Effects on Cardiac Functions Measured by Cardiac Magnetic Resonance Imaging in a Feline Model

    OpenAIRE

    Tzu-chi Lee; Jen-Hwey Chiu; Weng-Yih Tseng; Leang-Shin Wu; Krishna Kaphle; Jen-Hsou Lin; Chen-Haw Shih; Ying-Ling Wu

    2010-01-01

    The usefulness of acupuncture (AP) as a complementary and/or alternative therapy in animals is well established but more research is needed on its clinical efficacy relative to conventional therapy, and on the underlying mechanisms of the effects of AP. Cardiac magnetic resonance imaging (CMRI), an important tool in monitoring cardiovascular diseases, provides a reliable method to monitor the effects of AP on the cardiovascular system. This controlled experiment monitored the effect electro-a...

  4. Cardiac magnetic resonance imaging in patients with congenital heart disease

    International Nuclear Information System (INIS)

    The prevalence of congenital heart disease (CHD) is around 10 per 1000 live births in Germany. More than 90 % of these patients will survive into adulthood due to improvements in therapy. The classification of CHD may be based according to the anatomic structures involved, to the presence of an intracardiac shunt, the presence of a cyanosis and the intensity of therapy and complexity of the disease. Nearly half of all patients with CHD suffer from an intracardiac shunt, whereas complex cases such as patients with a tetralogy of Fallot or transposition of the great arteries are much more rare. Cardiac magnetic resonance imaging plays an important role in the work-up and follow-up of patients with CHD, especially after infancy and childhood. Depending on the abnormality in question, a multiparametric examination protocol is mandatory. Knowledge of operative procedures and findings of other imaging modalities help to optimize examination and time needed for it.

  5. Utility of Magnetic Resonance Imaging in Cardiac Venous Anatomic Variants

    International Nuclear Information System (INIS)

    The incidence of persistent left superior venacava (PLSVC) is approximately 0.5% in the general population; however,the coexistent absence of the right SVC has a reported incidence in tertiary centers of 0.1%. The vast majority of reports are limited to pediatric cardiology. Likewise, sinus of Valsalva aneurysm is a rare congenital anomaly, with a reported incidence of 0.1-3.5% of all congenital heart defects. We present a 71-year-old patient undergoing preoperative evaluation for incidental finding of aortic root aneurysm,and found to have all three in coexistence. Suggestive findings were demonstrated on cardiac catheterization and definitive diagnosis was made by magnetic resonance imaging. The use of MRI for the diagnosis of asymptomatic adult congenital heart disease will be reviewed

  6. The usefulness of magnetic resonance imaging (MRI) in cardiac myxoma

    International Nuclear Information System (INIS)

    The characteristics of cardiac myxoma on magnetic resonance imaging (MRI) were evaluated in 20 patients operated on from 1985 to 1991. MRI studies were performed with an 0.5-T system in 5 patients and an 0.15-T system in 15 patients using ECG gating. T1-weighted images (T1WI) were obtained in all 20 patients, T2-weighted images (T2WI) were obtained in 16, and Gd-DTPA-enhanced images were obtained in 9. MRI was able to correctly locate the myxoma and determine the site of attachment. MRI also correctly determined the shape of 19/20 tumors. The exception was an oval myxoma with a smooth but fibrotic and calcified margin, in which MRI visualized the signal void due to calcification as a villous surface. Myxomas showed an inhomogeneous intermediate intensity on T1WI and an inhomogeneous high intensity on T2WI. These findings were thought to be related to variations in the amount of cellular components, capillaries, and calcification within the myxoid matrix. A relatively high intensity on T1WI and enhancement was observed at the base of the myxomas, where less myxoid matrix and abundant vessels were seen histologically. A low intensity band was noted on T1WI just next to the base of 3 myxomas, and bundles of collagen fibers were observed at the same site histologically. MRI provided information about the internal architecture of these tumors, but the cause of the relatively high intensity area at the tumor based on T1WI remains unproven. In conclusion, MRI was reliable for the diagnosis of cardiac myxoma, and should be performed after cardiac ultrasonography. (author)

  7. New insights into peripartum cardiomyopathy using cardiac magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Renz, D.M.; Roettgen, R.; Wagner, M.; Elgeti, T. [Charite Universitaetsmedizin Berlin (Germany). Inst. fuer Radiologie; Habedank, D.; Dietz, R. [Charite Universitaetsmedizin Berlin (Germany). Medizinische Klinik mit Schwerpunkt Kardiologie; Boettcher, J. [SRH Wald-Klinikum Gera (Germany). Inst. fuer Diagnostische und Interventionelle Radiologie; Pfeil, A. [Jena Univ. (Germany). Klinik fuer Innere Medizin III; Kivelitz, D. [Asklepios Klinik St. Georg, Hamburg (Germany). Albers-Schoenberg-Institut fuer Strahlendiagnostik

    2011-09-15

    Purpose: The aim of this study was to evaluate a comprehensive cardiac magnetic resonance (MR) imaging approach in patients with peripartum cardiomyopathy (PPCM). The focus was on inflammatory myocardial changes. Materials and Methods: Retrospective analysis of 12 cardiac MR examinations was performed in 6 patients with PPCM. The protocol comprised cine sequences for the determination of chamber sizes and function. T2-weighted sequences for determination of edema (T2 ratio), T1-weighted images for measurement of early gadolinium enhancement ratio (EGER), and late gadolinium enhancement (LGE) sequences were used for tissue characterization. 5 examinations were performed during the acute stage, and 7 examinations were performed during the course of the disease. Results: Initially, 3 of 5 patients presented with an elevated left ventricular end-diastolic volume (LVEDV); in one patient, the LVEDV was in the upper range. In 4 of 5 subjects, the left ventricular ejection fraction (LVEF) was decreased. The T2 ratio and EGER values were initially elevated in all women. No LGE was detected in initial scans. In follow-up examinations, the LVEDV decreased and the LVEF increased in all patients. Tissue-characterizing parameters decreased to normal in all but 1 patient. 2 patients showing LGE did not present a favorable clinical course. Conclusion: Myocardial inflammation was detected in the acute stage of PPCM, which was mostly transient. In our small group, patients showing LGE had a non-favorable clinical course. Future studies should include tissue-characterizing parameters, such as T2 ratio and EGER. Thus, further insights into pathophysiology can be gained and therapeutic effects can be measured in a more extensive manner. (orig.)

  8. Acupuncture Effects on Cardiac Functions Measured by Cardiac Magnetic Resonance Imaging in a Feline Model

    Directory of Open Access Journals (Sweden)

    Jen-Hsou Lin

    2010-01-01

    Full Text Available The usefulness of acupuncture (AP as a complementary and/or alternative therapy in animals is well established but more research is needed on its clinical efficacy relative to conventional therapy, and on the underlying mechanisms of the effects of AP. Cardiac magnetic resonance imaging (CMRI, an important tool in monitoring cardiovascular diseases, provides a reliable method to monitor the effects of AP on the cardiovascular system. This controlled experiment monitored the effect electro-acupuncture (EA at bilateral acupoint Neiguan (PC6 on recovery time after ketamine/xylazine cocktail anesthesia in healthy cats. The CMRI data established the basic feline cardiac function index (CFI, including cardiac output and major vessel velocity. To evaluate the effect of EA on the functions of the autonomic nervous and cardiovascular systems, heart rate, respiration rate, electrocardiogram and pulse rate were also measured. Ketamine/xylazine cocktail anesthesia caused a transient hypertension in the cats; EA inhibited this anesthetic-induced hypertension and shortened the post-anesthesia recovery time. Our data support existing knowledge on the cardiovascular benefits of EA at PC6, and also provide strong evidence for the combination of anesthesia and EA to shorten post-anesthesia recovery time and counter the negative effects of anesthetics on cardiac physiology.

  9. Acupuncture effects on cardiac functions measured by cardiac magnetic resonance imaging in a feline model.

    Science.gov (United States)

    Lin, Jen-Hsou; Shih, Chen-Haw; Kaphle, Krishna; Wu, Leang-Shin; Tseng, Weng-Yih; Chiu, Jen-Hwey; Lee, Tzu-Chi; Wu, Ying-Ling

    2010-06-01

    The usefulness of acupuncture (AP) as a complementary and/or alternative therapy in animals is well established but more research is needed on its clinical efficacy relative to conventional therapy, and on the underlying mechanisms of the effects of AP. Cardiac magnetic resonance imaging (CMRI), an important tool in monitoring cardiovascular diseases, provides a reliable method to monitor the effects of AP on the cardiovascular system. This controlled experiment monitored the effect electro-acupuncture (EA) at bilateral acupoint Neiguan (PC6) on recovery time after ketamine/xylazine cocktail anesthesia in healthy cats. The CMRI data established the basic feline cardiac function index (CFI), including cardiac output and major vessel velocity. To evaluate the effect of EA on the functions of the autonomic nervous and cardiovascular systems, heart rate, respiration rate, electrocardiogram and pulse rate were also measured. Ketamine/xylazine cocktail anesthesia caused a transient hypertension in the cats; EA inhibited this anesthetic-induced hypertension and shortened the post-anesthesia recovery time. Our data support existing knowledge on the cardiovascular benefits of EA at PC6, and also provide strong evidence for the combination of anesthesia and EA to shorten post-anesthesia recovery time and counter the negative effects of anesthetics on cardiac physiology. PMID:18955311

  10. Cardiac energy metabolism probed with nuclear magnetic resonance. Chapter 12

    International Nuclear Information System (INIS)

    Nuclear magnetic resonance (NMR) spectroscopy possesses great potential for studying myocardial energy metabolism. To ensure that the observed NMR signal predominantly originates from the heart, localization is required, which can be achieved by excision or exposure of the heart, or by means of sophisticated NMR localization techniques. A number of different atomic nuclei have been employed. H-1 NMR has been mainly used to follow lactate accumulation is ischemic or anoxic hearts. C-13 NMR has been applied to study the fate of different substrates in the citric acid cycle and amino acid pools, and the role of glycogen metabolism in ischemia or anoxia. F-19, Na-23 and K-39 have been employed to investigate the consequences of altered energy metabolism for myocardial intracellular concentrations of Ca2+, Na+ and K+. The most abundantly used nucleus for studying myocardial energy metabolism is P-31. Numerous contributions have been made to the investigation of ischemia and reperfusion, protection of the heart against the consequences of ischemia and reperfusion, contractile failure, variation of high-energy phosphate levels over the cardiac cycle, regulation of oxidative phosphorylation and intracellular enzyme kinetics of both isolated perfused hearts and hearts in situ. Even human myocardial metabolism can be assessed by P-31 NMR, which is on the verge of becoming a clinical tool for investigating heart disease. 106 refs.; 3 figs.; 1 table

  11. A new stress test device for cardiac nuclear magnetic resonance studies

    International Nuclear Information System (INIS)

    A technique has been developed to exercise human subjects during acquisition of MRI and Magnetic Resonance Spectroscopy data in order to determine the effects of increased cardiac work on myocardial function and metabolism. (author). 6 refs.; 2 figs.; 1 tab

  12. Cardiac magnetic resonance T1 mapping of left atrial myocardium

    Science.gov (United States)

    Beinart, Roy; Khurram, Irfan M.; Liu, Songtao; Yarmohammadi, Hirad; Halperin, Henry R.; Bluemke, David A.; Gai, Neville; van der Geest, Rob J.; Lima, Joao A.C.; Calkins, Hugh; Zimmerman, Stefan L.; Nazarian, Saman

    2013-01-01

    BACKGROUND Cardiac magnetic resonance (CMR) T1 mapping is an emerging tool for objective quantification of myocardial fibrosis. OBJECTIVES To (a) establish the feasibility of left atrial (LA) T1 measurements, (b) determine the range of LA T1 values in patients with atrial fibrillation (AF) vs healthy volunteers, and (c) validate T1 mapping vs LA intracardiac electrogram voltage amplitude measures. METHODS CMR imaging at 1.5 T was performed in 51 consecutive patients before AF ablation and in 16 healthy volunteers. T1 measurements were obtained from the posterior LA myocardium by using the modified Look-Locker inversion-recovery sequence. Given the established association of reduced electrogram amplitude with fibrosis, intracardiac point-by-point bipolar LA voltage measures were recorded for the validation of T1 measurements. RESULTS The median LA T1 relaxation time was shorter in patients with AF (387 [interquartile range 364–428] ms) compared to healthy volunteers (459 [interquartile range 418–532] ms; P < .001) and was shorter in patients with AF with prior ablation compared to patients without prior ablation (P = .035). In a generalized estimating equations model, adjusting for data clusters per participant, age, rhythm during CMR, prior ablation, AF type, hypertension, and diabetes, each 100-ms increase in T1 relaxation time was associated with 0.1 mV increase in intracardiac bipolar LA voltage (P = .025). CONCLUSIONS Measurement of the LA myocardium T1 relaxation time is feasible and strongly associated with invasive voltage measures. This methodology may improve the quantification of fibrotic changes in thin-walled myocardial tissues. PMID:23643513

  13. Quadricuspid aortic valve by cardiac magnetic resonance imaging: a case report and review of the literature.

    Science.gov (United States)

    Khan, Shamruz Khan Akerem; Tamin, Syahidah Syed; Araoz, Philip A

    2011-01-01

    Quadricuspid aortic valve (QAV) is a rare congenital cardiac entity. The recognition of QAV has clinical significance as it causes aortic valve dysfunction, commonly aortic regurgitation, and is often associated with other congenital cardiac abnormalities. We showed the important role played by cardiac magnetic resonance imaging in detecting QAV and review the available literature to explain its incidence, diagnosis, classifications, embryology, correlation between morphology of the QAV and its function, associated conditions, and management. PMID:21926862

  14. T2-weighted cardiovascular magnetic resonance in acute cardiac disease

    OpenAIRE

    Eitel Ingo; Friedrich Matthias G

    2011-01-01

    Abstract Cardiovascular magnetic resonance (CMR) using T2-weighted sequences can visualize myocardial edema. When compared to previous protocols, newer pulse sequences with substantially improved image quality have increased its clinical utility. The assessment of myocardial edema provides useful incremental diagnostic and prognostic information in a variety of clinical settings associated with acute myocardial injury. In patients with acute chest pain, T2-weighted CMR is able to identify acu...

  15. Determinants of Left Ventricular Mass and Hypertrophy in Hemodialysis Patients Assessed by Cardiac Magnetic Resonance Imaging

    OpenAIRE

    Patel, Rajan K.; Oliver, Scott; Patrick B. Mark; Powell, Joanna R.; McQuarrie, Emily P.; Traynor, James P.; Dargie, Henry J; Jardine, Alan G

    2009-01-01

    Background and objectives: Left ventricular hypertrophy (LVH) is an independent risk factor for premature cardiovascular death in hemodialysis (HD) patients and one of the three forms of uremic cardiomyopathy. Cardiovascular magnetic resonance (CMR) is a volume-independent technique to assess cardiac structure. We used CMR to assess the determinants of left ventricular mass (LVM) and LVH in HD patients.

  16. Cardiac remodelling and function with primary mitral valve insufficiency studied by magnetic resonance imaging

    DEFF Research Database (Denmark)

    Aplin, Mark; Kyhl, Kasper; Bjerre, Jenny;

    2016-01-01

    AIMS: Evaluation of patients with primary mitral valve insufficiency (MI) is best supported by quantitative measures. Cardiovascular magnetic resonance imaging (CMR) offers flow and cardiac chamber volume quantification. We studied cardiac remodelling with CMR to determine MI regurgitation volumes...... (P < 0.05). In surgical patients, the MIVol correlated to the decrease in LV dimension after valve surgery (P < 0.02). CONCLUSION: CMR provides a reproducible quantitative technique for evaluation of MI, as MIVol and cardiac chamber volumes can be held against diagnostic cut-off values. The Aoflow...

  17. Coronary artery stent mimicking intracardiac thrombus on cardiac magnetic resonance imaging due to signal loss

    DEFF Research Database (Denmark)

    Qayyum, Abbas Ali; Vejlstrup, Niels Grove; Ahtarovski, Kiril Aleksov;

    2012-01-01

    Since the introduction of percutaneous coronary intervention for coronary artery disease, thousands of patients have been treated with the implantation of coronary stents. Moreover, several of the patients with coronary stent undergo cardiac magnetic resonance (CMR) imaging every year. This case...... report is of a 77-year-old man who was previously treated with the implantation of a coronary stent in the left circumflex artery. He underwent CMR imaging, which revealed a process 14×21 mm in the left atrium. Cardiac contrast computed tomography did not demonstrate any cardiac pathology. While the...

  18. Understanding the physiology of complex congenital heart disease using cardiac magnetic resonance imaging

    International Nuclear Information System (INIS)

    Complex congenital heart diseases are often associated with complex alterations in hemodynamics. Understanding these key hemodynamic changes is critical to making management decisions including surgery and postoperative management. Existing tools for imaging and hemodynamic assessment like echocardiography, computed tomography and cardiac catheterization have inherent limitations. Cardiac magnetic resonance imaging (MRI) is emerging as a powerful bouquet of tools that allow not only excellent imaging, but also a unique insight into hemodynamics. This article introduces the reader to cardiac MRI and its utility through the clinical example of a child with a complex congenital cyanotic heart disease

  19. Assessment of Myocardial Infarction by Cardiac Magnetic Resonance Imaging and Long-Term Mortality

    Directory of Open Access Journals (Sweden)

    João Luiz Fernandes Petriz

    2015-02-01

    Full Text Available Background: Cardiac magnetic resonance imaging provides detailed anatomical information on infarction. However, few studies have investigated the association of these data with mortality after acute myocardial infarction. Objective: To study the association between data regarding infarct size and anatomy, as obtained from cardiac magnetic resonance imaging after acute myocardial infarction, and long-term mortality. Methods: A total of 1959 reports of “infarct size” were identified in 7119 cardiac magnetic resonance imaging studies, of which 420 had clinical and laboratory confirmation of previous myocardial infarction. The variables studied were the classic risk factors – left ventricular ejection fraction, categorized ventricular function, and location of acute myocardial infarction. Infarct size and acute myocardial infarction extent and transmurality were analyzed alone and together, using the variable named “MET-AMI”. The statistical analysis was carried out using the elastic net regularization, with the Cox model and survival trees. Results: The mean age was 62.3 ± 12 years, and 77.3% were males. During the mean follow-up of 6.4 ± 2.9 years, there were 76 deaths (18.1%. Serum creatinine, diabetes mellitus and previous myocardial infarction were independently associated with mortality. Age was the main explanatory factor. The cardiac magnetic resonance imaging variables independently associated with mortality were transmurality of acute myocardial infarction (p = 0.047, ventricular dysfunction (p = 0.0005 and infarcted size (p = 0.0005; the latter was the main explanatory variable for ischemic heart disease death. The MET-AMI variable was the most strongly associated with risk of ischemic heart disease death (HR: 16.04; 95%CI: 2.64-97.5; p = 0.003. Conclusion: The anatomical data of infarction, obtained from cardiac magnetic resonance imaging after acute myocardial infarction, were independently associated with long

  20. Assessment of Myocardial Infarction by Cardiac Magnetic Resonance Imaging and Long-Term Mortality

    Energy Technology Data Exchange (ETDEWEB)

    Petriz, João Luiz Fernandes, E-mail: jlpetriz@cardiol.br [Universidade Federal do Rio de Janeiro (UFRJ) / Instituto do Coração Edson Saad - Programa de Pós Graduação em Medicina (Cardiologia), Rio de Janeiro, RJ (Brazil); Hospital Barra D’Or, Rio de Janeiro, RJ (Brazil); Instituto D’Or de Pesquisa e Ensino, Rio de Janeiro, RJ (Brazil); Gomes, Bruno Ferraz de Oliveira; Rua, Braulio Santos [Hospital Barra D’Or, Rio de Janeiro, RJ (Brazil); Azevedo, Clério Francisco [Instituto D’Or de Pesquisa e Ensino, Rio de Janeiro, RJ (Brazil); Hadlich, Marcelo Souza [Universidade Federal do Rio de Janeiro (UFRJ) / Instituto do Coração Edson Saad - Programa de Pós Graduação em Medicina (Cardiologia), Rio de Janeiro, RJ (Brazil); Instituto D’Or de Pesquisa e Ensino, Rio de Janeiro, RJ (Brazil); Mussi, Henrique Thadeu Periard [Universidade Federal do Rio de Janeiro (UFRJ) / Instituto do Coração Edson Saad - Programa de Pós Graduação em Medicina (Cardiologia), Rio de Janeiro, RJ (Brazil); Hospital Barra D’Or, Rio de Janeiro, RJ (Brazil); Taets, Gunnar de Cunto [Instituto D’Or de Pesquisa e Ensino, Rio de Janeiro, RJ (Brazil); Nascimento, Emília Matos do; Pereira, Basílio de Bragança; Silva, Nelson Albuquerque de Souza e [Universidade Federal do Rio de Janeiro (UFRJ) / Instituto do Coração Edson Saad - Programa de Pós Graduação em Medicina (Cardiologia), Rio de Janeiro, RJ (Brazil)

    2015-02-15

    Cardiac magnetic resonance imaging provides detailed anatomical information on infarction. However, few studies have investigated the association of these data with mortality after acute myocardial infarction. To study the association between data regarding infarct size and anatomy, as obtained from cardiac magnetic resonance imaging after acute myocardial infarction, and long-term mortality. A total of 1959 reports of “infarct size” were identified in 7119 cardiac magnetic resonance imaging studies, of which 420 had clinical and laboratory confirmation of previous myocardial infarction. The variables studied were the classic risk factors – left ventricular ejection fraction, categorized ventricular function, and location of acute myocardial infarction. Infarct size and acute myocardial infarction extent and transmurality were analyzed alone and together, using the variable named “MET-AMI”. The statistical analysis was carried out using the elastic net regularization, with the Cox model and survival trees. The mean age was 62.3 ± 12 years, and 77.3% were males. During the mean follow-up of 6.4 ± 2.9 years, there were 76 deaths (18.1%). Serum creatinine, diabetes mellitus and previous myocardial infarction were independently associated with mortality. Age was the main explanatory factor. The cardiac magnetic resonance imaging variables independently associated with mortality were transmurality of acute myocardial infarction (p = 0.047), ventricular dysfunction (p = 0.0005) and infarcted size (p = 0.0005); the latter was the main explanatory variable for ischemic heart disease death. The MET-AMI variable was the most strongly associated with risk of ischemic heart disease death (HR: 16.04; 95%CI: 2.64-97.5; p = 0.003). The anatomical data of infarction, obtained from cardiac magnetic resonance imaging after acute myocardial infarction, were independently associated with long-term mortality, especially for ischemic heart disease death.

  1. Measurements of pericardial adipose tissue using contrast enhanced cardiac multidetector computed tomography—comparison with cardiac magnetic resonance imaging

    DEFF Research Database (Denmark)

    Elming, Marie Bayer; Lønborg, Jacob; Rasmussen, Thomas;

    2013-01-01

    Recent studies have suggested that pericardial adipose tissue (PAT) located in close vicinity to the epicardial coronary arteries may play a role in the development of coronary artery disease. PAT has primarily been measured with cardiac magnetic resonance imaging (CMRI) or with non......-contrast cardiac multidetector computered tomography (MDCT) images. The aim of this study was to validate contrast MDCT derived measures of total PAT volume by a comparison to CMRI. In 52 patients, aged 60 years (34-81 years), Body Mass Index 28 kg/m(2) (18-39), and with stable ischemic heart disease, paired MDCT...

  2. Evaluation of cardiac tumors with magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Luna, Antonio [Clinica Las Nieves, MR Unit, Jaen (Spain); Ribes, Ramon [Reina Sofia Hospital, MR Unit, Radiology Department, Cordoba (Spain); Caro, Pilar [MR Unit, Dadisa, Cadiz (Spain); Vida, Jose [San Juan De Dios Hospital, MR Unit, Resalta, Cordoba (Spain); Erasmus, Jeremy J. [University of Texas, Department of Radiology, Houston, TX (United States)

    2005-07-01

    Primary cardiac neoplasms are rare, and are more commonly benign than malignant. However, metastases are by far the most common cardiac neoplasms. MRI allows evaluation of myocardial infiltration, pericardial involvement and/or extracardiac extension. MRI overcomes the usual limitations of echocardiography and assesses more accurately changes in cardiac function. Specific tumoral characterization is only possible in cases of myxoma, lipoma, fibroma and hemangioma. Suggestive features of malignancy are right side location, extracardiac extension, inhomogeneity in signal intensity of the tumor and pericardial effusion. The use of intravenous contrast material improves tumor characterization and depiction of tumor borders. MRI also allows differentiation of tumor from other nontumoral masses such as intracavitary tumors or fibromuscular elements of the posterior wall of the right atrium. (orig.)

  3. Utility of cardiac magnetic resonance in assessing right-sided heart failure in sarcoidosis

    International Nuclear Information System (INIS)

    Cardiac involvement in sarcoidosis is associated with a poor prognosis. In patients with right sided heart failure, differentiating between cor-pulmonale, or cardiac sarcoidosis has important implications to management. We present the case of a patient with severe but stable pulmonary sarcoidosis and new onset right sided heart failure despite only mild elevations of pulmonary artery pressure. CMR demonstration of extensive right ventricular fibrosis with associated dilatation and hypokinesis was a key finding for prognosis and management of the patient. Cardiac magnetic resonance (CMR) is the preferred investigation in the diagnosis of cardiac sarcoidosis, allowing assessment of myocardial inflammation and fibrosis, as well as function, in a manner not matched by other technologies

  4. Cardiac resynchronization therapy guided by cardiovascular magnetic resonance

    OpenAIRE

    Leyva Francisco

    2010-01-01

    Abstract Cardiac resynchronization therapy (CRT) is an established treatment for patients with symptomatic heart failure, severely impaired left ventricular (LV) systolic dysfunction and a wide (> 120 ms) complex. As with any other treatment, the response to CRT is variable. The degree of pre-implant mechanical dyssynchrony, scar burden and scar localization to the vicinity of the LV pacing stimulus are known to influence response and outcome. In addition to its recognized role in the assessm...

  5. Cardiac Magnetic Resonance Characterizes Myocarditis in a 16-Year-Old Female With Lyme Disease.

    Science.gov (United States)

    Avitabile, Catherine M; Harris, Matthew A; Chowdhury, Devyani

    2016-05-01

    Myocarditis may occur during early disseminated Lyme disease. A 16-year-old girl with serologic evidence of Borrelia burgdorferi infection and transient first-degree atrioventricular block underwent cardiac magnetic resonance imaging, which demonstrated myocardial hyperemia, edema, and delayed gadolinium enhancement. We discuss the use of T1- and T2-weighted dark blood sequences in addition to inversion recovery delayed enhancement imaging to support the diagnosis of Lyme myocarditis. PMID:26701623

  6. Cardiac magnetic resonance imaging parameters as surrogate endpoints in clinical trials of acute myocardial infarction

    OpenAIRE

    Gutberlet Matthias; Lurz Philipp; Fuernau Georg; de Waha Suzanne; Eitel Ingo; Desch Steffen; Schuler Gerhard; Thiele Holger

    2011-01-01

    Abstract Cardiac magnetic resonance (CMR) offers a variety of parameters potentially suited as surrogate endpoints in clinical trials of acute myocardial infarction such as infarct size, myocardial salvage, microvascular obstruction or left ventricular volumes and ejection fraction. The present article reviews each of these parameters with regard to the pathophysiological basis, practical aspects, validity, reliability and its relative value (strengths and limitations) as compared to competit...

  7. Delayed contrast enhancement cardiac magnetic resonance imaging in trastuzumab induced cardiomyopathy

    OpenAIRE

    Kirkpatrick Iain; Fang Tielan; Lytwyn Matthew; Fallah-Rad Nazanin; Jassal Davinder S

    2008-01-01

    Abstract Background Trastuzumab (Herceptin), an antagonist to the human epidermal growth factor 2 (HER2) receptor significantly decreases the rates of breast cancer recurrence and mortality by 50%. Despite therapeutic benefits, the risk of cardiotoxicity with trastuzumab ranges from 10–15% when administered sequentially following anthraycline chemotherapy. Little is known about the utility of cardiac magnetic resonance (CMR) in the assessment of trastuzumab mediated cardiomyopathy. Methods an...

  8. Simplified post processing of cine DENSE cardiovascular magnetic resonance for quantification of cardiac mechanics

    OpenAIRE

    Suever, Jonathan D.; Wehner, Gregory J.; Haggerty, Christopher M.; Jing, Linyuan; Hamlet, Sean M; Binkley, Cassi M.; Kramer, Sage P.; Mattingly, Andrea C.; Powell, David K.; Bilchick, Kenneth C.; Epstein, Frederick H.; Fornwalt, Brandon K

    2014-01-01

    Background Cardiovascular magnetic resonance using displacement encoding with stimulated echoes (DENSE) is capable of assessing advanced measures of cardiac mechanics such as strain and torsion. A potential hurdle to widespread clinical adoption of DENSE is the time required to manually segment the myocardium during post-processing of the images. To overcome this hurdle, we proposed a radical approach in which only three contours per image slice are required for post-processing (instead of th...

  9. Extra-cardiac findings in cardiovascular magnetic resonance: what the imaging cardiologist needs to know.

    Science.gov (United States)

    Rodrigues, Jonathan C L; Lyen, Stephen M; Loughborough, William; Amadu, Antonio Matteo; Baritussio, Anna; Dastidar, Amardeep Ghosh; Manghat, Nathan E; Bucciarelli-Ducci, Chiara

    2016-01-01

    Cardiovascular magnetic resonance (CMR) is an established non-invasive technique to comprehensively assess cardiovascular structure and function in a variety of acquired and inherited cardiac conditions. A significant amount of the neck, thorax and upper abdomen are imaged at the time of routine clinical CMR, particularly in the initial multi-slice axial and coronal images. The discovery of unsuspected disease at the time of imaging has ethical, financial and medico-legal implications. Extra-cardiac findings at the time of CMR are common, can be important and can change clinical management. Certain patient groups undergoing CMR are at particular risk of important extra-cardiac findings as several of the cardiovascular risk factors for atherosclerosis are also risk factors for malignancy. Furthermore, the presence of certain extra-cardiac findings may contribute to the interpretation of the primary cardiac pathology as some cardiac conditions have multi-systemic extra-cardiac involvement. The aim of this review is to give an overview of the type of extra-cardiac findings that may become apparent on CMR, subdivided by anatomical location. We focus on normal variant anatomy that may mimic disease, common incidental extra-cardiac findings and important imaging signs that help distinguish sinister pathology from benign disease. We also aim to provide a framework to the approach and potential further diagnostic work-up of incidental extra-cardiac findings discovered at the time of CMR. However, it is beyond the scope of this review to discuss and determine the clinical significance of extracardiac findings at CMR. PMID:27156861

  10. Evaluation of apical subtype of hypertrophic cardiomyopathy using cardiac magnetic resonance imaging with gadolinium enhancement.

    Science.gov (United States)

    Kebed, Kalie Y; Al Adham, Raed I; Bishu, Kalkidan; Askew, J Wells; Klarich, Kyle W; Araoz, Philip A; Foley, Thomas A; Glockner, James F; Nishimura, Rick A; Anavekar, Nandan S

    2014-09-01

    Apical hypertrophic cardiomyopathy (HC) is an uncommon variant of HC. We sought to characterize cardiac magnetic resonance imaging (MRI) findings among apical HC patients. This was a retrospective review of consecutive patients with a diagnosis of apical HC who underwent cardiac MRI examinations at the Mayo Clinic (Rochester, MN) from August 1999 to October 2011. Clinical and demographic data at the time of cardiac MRI study were abstracted. Cardiac MRI study and 2-dimensional echocardiograms performed within 6 months of the cardiac MRI were reviewed; 96 patients with apical HC underwent cardiac MRI examinations. LV end-diastolic and end-systolic volumes were 130.7 ± 39.1 ml and 44.2 ± 20.9 ml, respectively. Maximum LV thickness was 19 ± 5 mm. Hypertrophy extended beyond the apex into other segments in 57 (59.4%) patients. Obstructive physiology was seen in 12 (12.5%) and was more common in the mixed apical phenotype than the pure apical (19.3 vs 2.6%, p = 0.02). Apical pouches were noted in 39 (40.6%) patients. Late gadolinium enhancement (LGE) was present in 70 (74.5%) patients. LGE was associated with severe symptoms and increased maximal LV wall thickness. In conclusion, cardiac MRI is well suited for studying the apical form of HC because of difficulty imaging the cardiac apex with standard echocardiography. Cardiac MRI is uniquely suited to delineate the presence or absence of an apical pouch and abnormal myocardial LGE that may have implications in the natural history of apical HM. In particular, the presence of abnormal LGE is associated with clinical symptoms and increased wall thickness. PMID:25037678

  11. Evaluation of cardiac structures and function in hypertrophic cardiomyopathy with magnetic resonance imaging

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Objective:To assess the capability of magnetic resonance imaging(MRI)in evaluating the cardiac structures and function in the hypertrophic cardiomyopathy(HCM).Methods:Fourteen healthy volunteers and eighteen cases with HCM verified by history,clinical presentation,electrocardiogram and echocardiography(ECG)were performed with MRI.The myocardial thickness of interventricular septum at the basal segment and that of posterolateral free wall of the left ventricle(LV)were measured.Some indexes for evaluating cardiac function were measured using ARGUS auto-quantitative program.Resuits:The myocardial thickness of septum at the basal segment had significant difference between the HCM patients and the healthy volunteers.There was no significant difference between MRI and ECG in examining end-diastolic volume,ejection fraction of the LV.Conclusion:MRI can fully provide more information on the abnormalities of cardiac anatomy and function;thus,it is of great value in clinical application.

  12. Valve area and cardiac output in aortic stenosis: quantification by magnetic resonance velocity mapping

    DEFF Research Database (Denmark)

    Søndergaard, Lise; Hildebrandt, P; Lindvig, K;

    1993-01-01

    Valve area and cardiac output were determined with magnetic resonance (MR) velocity mapping in 12 patients with aortic stenosis. Heart catheterization, Doppler echocardiography, and indicator dilution were performed for comparison. Left ventricle could be catheterized in only nine patients; in...... material, MR measured a mean area of 1.1 cm2 compared with 1.2 cm2 derived from Doppler echocardiography data, with a mean difference of 0.1 cm2 and [-0.5, +0.6] cm2 as limits of agreement. In 11 patients the cardiac output was quantified by MR to a mean of 4.9 L/min and by indicator dilution to 5.0 L......--the valvular area and the cardiac output--may be quantified, MR has potential to become a clinical tool in assessment of severity in aortic stenosis....

  13. Denoising human cardiac diffusion tensor magnetic resonance images using sparse representation combined with segmentation

    Science.gov (United States)

    Bao, L. J.; Zhu, Y. M.; Liu, W. Y.; Croisille, P.; Pu, Z. B.; Robini, M.; Magnin, I. E.

    2009-03-01

    Cardiac diffusion tensor magnetic resonance imaging (DT-MRI) is noise sensitive, and the noise can induce numerous systematic errors in subsequent parameter calculations. This paper proposes a sparse representation-based method for denoising cardiac DT-MRI images. The method first generates a dictionary of multiple bases according to the features of the observed image. A segmentation algorithm based on nonstationary degree detector is then introduced to make the selection of atoms in the dictionary adapted to the image's features. The denoising is achieved by gradually approximating the underlying image using the atoms selected from the generated dictionary. The results on both simulated image and real cardiac DT-MRI images from ex vivo human hearts show that the proposed denoising method performs better than conventional denoising techniques by preserving image contrast and fine structures.

  14. The role of cardiac magnetic resonance imaging following acute myocardial infarction

    Energy Technology Data Exchange (ETDEWEB)

    Wong, Dennis T.L.; Richardson, James D.; Puri, Rishi; Nelson, Adam J.; Teo, Karen S.L.; Worthley, Matthew I. [Royal Adelaide Hospital, Cardiovascular Research Centre, Adelaide (Australia); University of Adelaide, Department of Medicine, Adelaide (Australia); Bertaso, Angela G. [Royal Adelaide Hospital, Cardiovascular Research Centre, Adelaide (Australia); Worthley, Stephen G. [Royal Adelaide Hospital, Cardiovascular Research Centre, Adelaide (Australia); University of Adelaide, Department of Medicine, Adelaide (Australia); Cardiovascular Investigational Unit, Adelaide, SA (Australia)

    2012-08-15

    Advances in the management of myocardial infarction have resulted in substantial reductions in morbidity and mortality. However, after acute treatment a number of diagnostic and prognostic questions often remain to be answered, whereby cardiac imaging plays an essential role. For example, some patients will sustain early mechanical complications after infarction, while others may develop significant ventricular dysfunction. Furthermore, many individuals harbour a significant burden of residual coronary disease for which clarification of functional ischaemic status and/or viability of the suspected myocardial territory is required. Cardiac magnetic resonance (CMR) imaging is well positioned to fulfil these requirements given its unparalleled capability in evaluating cardiac function, stress ischaemia testing and myocardial tissue characterisation. This review will focus on the utility of CMR in resolving diagnostic uncertainty, evaluating early complications following myocardial infarction, assessing inducible ischaemia, myocardial viability, ventricular remodelling and the emerging role of CMR-derived measures as endpoints in clinical trials. (orig.)

  15. Clinical relevance and indications for cardiac magnetic resonance imaging 2013. An interdisciplinary expert statement

    International Nuclear Information System (INIS)

    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.)

  16. Value of cardiac 320-multidetector computed tomography and cardiac magnetic resonance imaging for assessment of myocardial perfusion defects in patients with known chronic ischemic heart disease

    DEFF Research Database (Denmark)

    Qayyum, Abbas Ali; Kühl, Jørgen T; Mathiasen, Anders B;

    2013-01-01

    The challenge for therapies targeting perfusion abnormalities is to identify and evaluate the region of interest. The aim of this study was to compare rest and stress myocardial perfusion measured by cardiac multi-detector computed tomography (MDCT) and cardiac magnetic resonance (CMR) imaging in...

  17. Feasibility of Rapid-Sequence 31P Magnetic Resonance Spectroscopy in Cardiac Patients

    International Nuclear Information System (INIS)

    Purpose: To determine the clinical feasibility of rapid-sequence phosphorus-31 magnetic resonance spectroscopy (31P -MRS) of the heart with cardiac patients using a 5T clinical MR system. Material and Methods: Twenty cardiac patients, i.e. dilated cardiomyopathy (DCM)3 cases, hypertrophic cardiomyopathy (HCM) 3 cases, hypertensive heart diseases (HHD) 3 cases, and aortic regurgitation (AR) case were examined using rapid cardiac 31P-MRS. Complete three-dimensional localization was performed using a two-dimensional phosphorus chemical-shift imaging sequence in combination with 30-mm axial slice-selective excitation. The rapid-sequence 31P-MRS procedure was phase encoded in arrays of 8x8 steps with an average of 4 acquisitions. The total examination time, including proton imaging and shimming, for the rapid cardiac 31P-MRS procedure, ranged from 0 to 5 min, depending on the heart rate. Student's t test was used to compare creatine phosphate (PCr)/adenosine triphosphate (ATP) ratios from the cardiac patients with those of the control subjects (n≅13). Results: The myocardial PCr/ATP ratio obtained by rapid 31P-MRS was significantly lower (P 31P-MRS may be a valid diagnostic tool for patients with cardiac disease

  18. Extracardiac findings detected by cardiac magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Wyttenbach, Rolf; Medioni, Nathalie; Santini, Paolo [Ospedale San Giovanni Bellinzona (EOC), Department of Radiology, Bellinzona (Switzerland); Vock, Peter [University Hospital Bern, Department of Diagnostic, Interventional and Paediatric Radiology, Bern (Switzerland); Szucs-Farkas, Zsolt [University Hospital Bern, Department of Diagnostic, Interventional and Paediatric Radiology, Bern (Switzerland); Spitalzentrum Biel AG, Department of Radiology, Biel (Switzerland)

    2012-06-15

    To determine the prevalence and importance of extracardiac findings (ECF) in patients undergoing clinical CMR and to test the hypothesis that the original CMR reading focusing on the heart may underestimate extracardiac abnormalities. 401 consecutive patients (mean age 53 years) underwent CMR at 1.5 T. Main indications were ischaemic heart disease (n = 183) and cardiomyopathy (n = 164). All CMR sequences, including scout images, were reviewed with specific attention to ECF in a second reading by the same radiologist who performed the first clinical reading. Potentially significant findings were defined as abnormalities requiring additional clinical or radiological follow-up. 250 incidental ECF were detected, of which 84 (34%) had potentially significant ECF including bronchial carcinoma (n = 1), lung consolidation (n = 7) and abdominal abnormalities. In 166 CMR studies (41%) non-significant ECF were detected. The number of ECF identified at second versus first reading was higher for significant (84 vs. 47) and non-significant (166 vs. 36) findings (P < 0.00001). About one fifth of patients undergoing CMR were found to have potentially significant ECF requiring additional work-up. The second dedicated reading detected significantly more ECF compared with the first clinical reading emphasising the importance of active search for extracardiac abnormalities when evaluating CMR studies. circle Many patients undergoing cardiac MR have significant extracardiac findings (ECF) circle These impact on management and require additional work-up. circle Wide review of scout and cine sequences will detect most ECFs. circle Education of radiologists is important to identify ECFs on CMR studies. (orig.)

  19. Ventricular function following coronary artery bypass grafting: comparison between Gated SPECT and cardiac magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Mesquita, Claudio Tinoco [Hospital Pro-Cardiaco, Rio de Janeiro, RJ (Brazil). Servico de Medicina Nuclear; Instituto Nacional de Cardiologia, Rio de Janeiro, RJ (Brazil); Pessoa, Maria Carolina Pinheiro [Pro-Echo Hospital Samaritano, Rio de Janeiro, RJ (Brazil); Vasconcelos, Paulo Pontes [Centro de Diagnostico por Imagens (CDPI), Rio de Janeiro, RJ (Brazil); Oliveira Junior, Amarino Carvalho [Hospital Pro-Cardiaco, Rio de Janeiro, RJ (Brazil). Servico de Radiologia; Dohmann, Hans Fernando Rocha [Hospital Pro-Cardiaco, Rio de Janeiro, RJ (Brazil). Servico de Radiologia; Instituto Nacional de Cardiologia, Rio de Janeiro, RJ (Brazil); Reis, Adair Gomes dos [Nuclear Diagnosticos, SP (Brazil); Fonseca, Lea Mirian Barbosa da [Pro-Echo Hospital Samaritano, Rio de Janeiro, RJ (Brazil); Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil)

    2009-04-15

    Background: The assessment of left ventricular function may be impaired by the abnormal interventricular septal motion frequently found after coronary artery bypass grafting (CABG). Studies on the validation of gated SPECT as a tool for the assessment of left ventricular function in this patient group are scarce. Objective: We investigated the agreement and correlation between left ventricular ejection fraction (LVEF), end-diastolic volume (EDV), and end-systolic volume (ESV) as obtained using electrocardiogram-gated myocardial perfusion scintigraphy (gated SPECT) and cardiac magnetic resonance imaging in 20 patients undergoing coronary artery bypass grafting. Methods: Correlation was measured using Spearman's correlation coefficient ({rho}). Agreement was assessed using Bland-Altman analysis. Results: A good correlation was found between gated SPECT and cardiac magnetic resonance imaging in patients after CABG with regard to left ventricular ejection fraction ({rho} = 0.85; p =0.0001), moderate correlation for end-diastolic volume ({rho} = 0.51; p = 0.02), and non-significant correlation for end-diastolic volume ({rho} = 0.13; p = 0.5). Agreement ranges for LVEF, ESV and EDV were: -20% to 12%; -38 to 54 ml and; -96 to 100 ml, respectively. Conclusion: A reliable correlation was found for left ventricular ejection fraction as obtained by gated SPECT and magnetic resonance imaging in patients undergoing CABG. For ventricular volumes, however, the correlation is not adequate. (author)

  20. Functional Relevance of Coronary Artery Disease by Cardiac Magnetic Resonance and Cardiac Computed Tomography: Myocardial Perfusion and Fractional Flow Reserve

    Directory of Open Access Journals (Sweden)

    Gianluca Pontone

    2015-01-01

    Full Text Available Coronary artery disease (CAD is one of the leading causes of morbidity and mortality and it is responsible for an increasing resource burden. The identification of patients at high risk for adverse events is crucial to select those who will receive the greatest benefit from revascularization. To this aim, several non-invasive functional imaging modalities are usually used as gatekeeper to invasive coronary angiography, but the diagnostic yield of elective invasive coronary angiography remains unfortunately low. Stress myocardial perfusion imaging by cardiac magnetic resonance (stress-CMR has emerged as an accurate technique for diagnosis and prognostic stratification of the patients with known or suspected CAD thanks to high spatial and temporal resolution, absence of ionizing radiation, and the multiparametric value including the assessment of cardiac anatomy, function, and viability. On the other side, cardiac computed tomography (CCT has emerged as unique technique providing coronary arteries anatomy and more recently, due to the introduction of stress-CCT and noninvasive fractional flow reserve (FFR-CT, functional relevance of CAD in a single shot scan. The current review evaluates the technical aspects and clinical experience of stress-CMR and CCT in the evaluation of functional relevance of CAD discussing the strength and weakness of each approach.

  1. Cardiac magnetic resonance imaging parameters as surrogate endpoints in clinical trials of acute myocardial infarction

    Directory of Open Access Journals (Sweden)

    Gutberlet Matthias

    2011-09-01

    Full Text Available Abstract Cardiac magnetic resonance (CMR offers a variety of parameters potentially suited as surrogate endpoints in clinical trials of acute myocardial infarction such as infarct size, myocardial salvage, microvascular obstruction or left ventricular volumes and ejection fraction. The present article reviews each of these parameters with regard to the pathophysiological basis, practical aspects, validity, reliability and its relative value (strengths and limitations as compared to competitive modalities. Randomized controlled trials of acute myocardial infarction which have used CMR parameters as a primary endpoint are presented.

  2. Cardiac magnetic resonance imaging and computed tomography in ischemic cardiomyopathy: an update

    Directory of Open Access Journals (Sweden)

    Fernanda Boldrini Assunção

    2016-02-01

    Full Text Available Abstract Ischemic cardiomyopathy is one of the major health problems worldwide, representing a significant part of mortality in the general population nowadays. Cardiac magnetic resonance imaging (CMRI and cardiac computed tomography (CCT are noninvasive imaging methods that serve as useful tools in the diagnosis of coronary artery disease and may also help in screening individuals with risk factors for developing this illness. Technological developments of CMRI and CCT have contributed to the rise of several clinical indications of these imaging methods complementarily to other investigation methods, particularly in cases where they are inconclusive. In terms of accuracy, CMRI and CCT are similar to the other imaging methods, with few absolute contraindications and minimal risks of adverse side-effects. This fact strengthens these methods as powerful and safe tools in the management of patients. The present study is aimed at describing the role played by CMRI and CCT in the diagnosis of ischemic cardiomyopathies.

  3. Cardiac magnetic resonance imaging and computed tomography in ischemic cardiomyopathy: an update

    International Nuclear Information System (INIS)

    Ischemic cardiomyopathy is one of the major health problems worldwide, representing a significant part of mortality in the general population nowadays. Cardiac magnetic resonance imaging (CMRI) and cardiac computed tomography (CCT) are noninvasive imaging methods that serve as useful tools in the diagnosis of coronary artery disease and may also help in screening individuals with risk factors for developing this illness. Technological developments of CMRI and CCT have contributed to the rise of several clinical indications of these imaging methods complimentarily to other investigation methods, particularly in cases where they are inconclusive. In terms of accuracy, CMRI and CCT are similar to the other imaging methods, with few absolute contraindications and minimal risks of adverse side-effects. This fact strengthens these methods as powerful and safe tools in the management of patients. The present study is aimed at describing the role played by CMRI and CCT in the diagnosis of ischemic cardiomyopathies. (author)

  4. Cardiac magnetic resonance imaging and computed tomography in ischemic cardiomyopathy: an update

    Energy Technology Data Exchange (ETDEWEB)

    Assuncao, Fernanda Boldrini; Oliveira, Diogo Costa Leandro de; Nacif, Marcelo Souto, E-mail: msnacif@gmail.com [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Escola de Medicina; Souza, Vitor Frauches [Complexo Hospitalar de Niteroi (CHN), Niteroi, RJ (Brazil)

    2016-01-15

    Ischemic cardiomyopathy is one of the major health problems worldwide, representing a significant part of mortality in the general population nowadays. Cardiac magnetic resonance imaging (CMRI) and cardiac computed tomography (CCT) are noninvasive imaging methods that serve as useful tools in the diagnosis of coronary artery disease and may also help in screening individuals with risk factors for developing this illness. Technological developments of CMRI and CCT have contributed to the rise of several clinical indications of these imaging methods complimentarily to other investigation methods, particularly in cases where they are inconclusive. In terms of accuracy, CMRI and CCT are similar to the other imaging methods, with few absolute contraindications and minimal risks of adverse side-effects. This fact strengthens these methods as powerful and safe tools in the management of patients. The present study is aimed at describing the role played by CMRI and CCT in the diagnosis of ischemic cardiomyopathies. (author)

  5. Cardiac chamber quantification using magnetic resonance imaging at 7 Tesla - a pilot study

    International Nuclear Information System (INIS)

    Interest in cardiovascular magnetic resonance (CMR) at 7 T is motivated by the expected increase in spatial and temporal resolution, but the method is technically challenging. We examined the feasibility of cardiac chamber quantification at 7 T. A stack of short axes covering the left ventricle was obtained in nine healthy male volunteers. At 1.5 T, steady-state free precession (SSFP) and fast gradient echo (FGRE) cine imaging with 7 mm slice thickness (STH) were used. At 7 T, FGRE with 7 mm and 4 mm STH were applied. End-diastolic volume, end-systolic volume, ejection fraction and mass were calculated. All 7 T examinations provided excellent blood/myocardium contrast for all slice directions. No significant difference was found regarding ejection fraction and cardiac volumes between SSFP at 1.5 T and FGRE at 7 T, while volumes obtained from FGRE at 1.5 T were underestimated. Cardiac mass derived from FGRE at 1.5 and 7 T was larger than obtained from SSFP at 1.5 T. Agreement of volumes and mass between SSFP at 1.5 T and FGRE improved for FGRE at 7 T when combined with an STH reduction to 4 mm. This pilot study demonstrates that cardiac chamber quantification at 7 T using FGRE is feasible and agrees closely with SSFP at 1.5 T. (orig.)

  6. Cardiac chamber quantification using magnetic resonance imaging at 7 Tesla - a pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Knobelsdorff-Brenkenhoff, Florian von; Schulz-Menger, Jeanette [HELIOS Klinikum Berlin-Buch, Department of Cardiology and Nephrology, Berlin (Germany); Medical University Berlin, Charite Campus Buch, Experimental and Clinical Research Center (ECRC), Working Group on Cardiovascular Magnetic Resonance, Berlin (Germany); Max Delbrueck Center for Molecular Medicine, Berlin Ultrahigh Field Facility, Berlin (Germany); Frauenrath, Tobias; Hezel, Fabian [Max Delbrueck Center for Molecular Medicine, Berlin Ultrahigh Field Facility, Berlin (Germany); Prothmann, Marcel [Medical University Berlin, Charite Campus Buch, Experimental and Clinical Research Center (ECRC), Working Group on Cardiovascular Magnetic Resonance, Berlin (Germany); Dieringer, Matthias A.; Niendorf, Thoralf [Medical University Berlin, Charite Campus Buch, Experimental and Clinical Research Center (ECRC), Working Group on Cardiovascular Magnetic Resonance, Berlin (Germany); Max Delbrueck Center for Molecular Medicine, Berlin Ultrahigh Field Facility, Berlin (Germany); Renz, Wolfgang [Max Delbrueck Center for Molecular Medicine, Berlin Ultrahigh Field Facility, Berlin (Germany); Siemens Healthcare, Erlangen (Germany); Kretschel, Kerstin [HELIOS Klinikum Berlin-Buch, Department of Cardiology and Nephrology, Berlin (Germany); Medical University Berlin, Charite Campus Buch, Experimental and Clinical Research Center (ECRC), Working Group on Cardiovascular Magnetic Resonance, Berlin (Germany)

    2010-12-15

    Interest in cardiovascular magnetic resonance (CMR) at 7 T is motivated by the expected increase in spatial and temporal resolution, but the method is technically challenging. We examined the feasibility of cardiac chamber quantification at 7 T. A stack of short axes covering the left ventricle was obtained in nine healthy male volunteers. At 1.5 T, steady-state free precession (SSFP) and fast gradient echo (FGRE) cine imaging with 7 mm slice thickness (STH) were used. At 7 T, FGRE with 7 mm and 4 mm STH were applied. End-diastolic volume, end-systolic volume, ejection fraction and mass were calculated. All 7 T examinations provided excellent blood/myocardium contrast for all slice directions. No significant difference was found regarding ejection fraction and cardiac volumes between SSFP at 1.5 T and FGRE at 7 T, while volumes obtained from FGRE at 1.5 T were underestimated. Cardiac mass derived from FGRE at 1.5 and 7 T was larger than obtained from SSFP at 1.5 T. Agreement of volumes and mass between SSFP at 1.5 T and FGRE improved for FGRE at 7 T when combined with an STH reduction to 4 mm. This pilot study demonstrates that cardiac chamber quantification at 7 T using FGRE is feasible and agrees closely with SSFP at 1.5 T. (orig.)

  7. Cardiac dysfunction in the diabetic rat: quantitative evaluation using high resolution magnetic resonance imaging

    Directory of Open Access Journals (Sweden)

    Alenezy Mohammed D

    2006-04-01

    Full Text Available Abstract Background Diabetes is a major risk factor for cardiovascular disease. In particular, type 1 diabetes compromises the cardiac function of individuals at a relatively early age due to the protracted course of abnormal glucose homeostasis. The functional abnormalities of diabetic myocardium have been attributed to the pathological changes of diabetic cardiomyopathy. Methods In this study, we used high field magnetic resonance imaging (MRI to evaluate the left ventricular functional characteristics of streptozotocin treated diabetic Sprague-Dawley rats (8 weeks disease duration in comparison with age/sex matched controls. Results Our analyses of EKG gated cardiac MRI scans of the left ventricle showed a 28% decrease in the end-diastolic volume and 10% increase in the end-systolic volume of diabetic hearts compared to controls. Mean stroke volume and ejection fraction in diabetic rats were decreased (48% and 28%, respectively compared to controls. Further, dV/dt changes were suggestive of phase sensitive differences in left ventricular kinetics across the cardiac cycle between diabetic and control rats. Conclusion Thus, the MRI analyses of diabetic left ventricle suggest impairment of diastolic and systolic hemodynamics in this rat model of diabetic cardiomyopathy. Our studies also show that in vivo MRI could be used in the evaluation of cardiac dysfunction in this rat model of type 1 diabetes.

  8. [Research of Left Ventricle Function Analysis Using Real-time Cardiac Magnetic Resonance Imaging].

    Science.gov (United States)

    Yang, Fan; He, Yan; Zhang, Jie; Wu, Yin

    2015-12-01

    Real-time free breathing cardiac cine imaging is a reproducible method with shorter acquisition time and without breath-hold for cardiac magnetic resonance imaging. However, the detection of end-diastole and end-systole frames of real-time free breathing cardiac cine imaging for left ventricle function analysis is commonly completed by visual identification, which is time-consuming and laborious. In order to save processing time, we propose a method for semi-automatic identification of end-diastole and end-systole frames. The method fits respiratory motion signal and acquires the expiration phase, end-diastole and end-systole frames by cross correlation coefficient. The procedure successfully worked on ten healthy volunteers and validated by the analysis of left ventricle function compared to the standard breath-hold steady-state free precession cardiac cine imaging without any significant statistical differences. The results demonstrated that the present method could correctly detect end-diastole and end-systole frames. In the future, this technique may be used for rapid left ventricle function analysis in clinic. PMID:27079101

  9. Feasibility of Rapid-Sequence {sup 31}P Magnetic Resonance Spectroscopy in Cardiac Patients

    Energy Technology Data Exchange (ETDEWEB)

    Chida, K.; Otani, H.; Saito, H.; Nagasaka, T.; Kagaya, Y.; Kohzuki, M.; Zuguchi, M.; Shirato, K. [Tohoku Univ., School of Health Sciences, Sendai (Japan). Dept. of Radiological Technology

    2005-07-01

    Purpose: To determine the clinical feasibility of rapid-sequence phosphorus-31 magnetic resonance spectroscopy ({sup 31}P -MRS) of the heart with cardiac patients using a 5T clinical MR system. Material and Methods: Twenty cardiac patients, i.e. dilated cardiomyopathy (DCM)3 cases, hypertrophic cardiomyopathy (HCM) 3 cases, hypertensive heart diseases (HHD) 3 cases, and aortic regurgitation (AR) case were examined using rapid cardiac {sup 31}P-MRS. Complete three-dimensional localization was performed using a two-dimensional phosphorus chemical-shift imaging sequence in combination with 30-mm axial slice-selective excitation. The rapid-sequence {sup 31}P-MRS procedure was phase encoded in arrays of 8x8 steps with an average of 4 acquisitions. The total examination time, including proton imaging and shimming, for the rapid cardiac {sup 31}P-MRS procedure, ranged from 0 to 5 min, depending on the heart rate. Student's t test was used to compare creatine phosphate (PCr)/adenosine triphosphate (ATP) ratios from the cardiac patients with those of the control subjects (n{approx_equal}13). Results: The myocardial PCr/ATP ratio obtained by rapid {sup 31}P-MRS was significantly lower (P <0.001) in DCM patients (1.82{+-}0.33, mean{+-}SD), and in patients with global myocardial dysfunction (combined data for 20 patients:.89{+-}0.32) than in normal volunteers (2.96{+-}0.59). These results are similar to previous studies. Conclusion: Rapid-sequence {sup 31}P-MRS may be a valid diagnostic tool for patients with cardiac disease.

  10. Progress and promises of human cardiac magnetic resonance at ultrahigh fields: A physics perspective

    Science.gov (United States)

    Niendorf, Thoralf; Graessl, Andreas; Thalhammer, Christof; Dieringer, Matthias A.; Kraus, Oliver; Santoro, Davide; Fuchs, Katharina; Hezel, Fabian; Waiczies, Sonia; Ittermann, Bernd; Winter, Lukas

    2013-04-01

    A growing number of reports eloquently speak about explorations into cardiac magnetic resonance (CMR) at ultrahigh magnetic fields (B0 ⩾ 7.0 T). Realizing the progress, promises and challenges of ultrahigh field (UHF) CMR this perspective outlines current trends in enabling MR technology tailored for cardiac MR in the short wavelength regime. For this purpose many channel radiofrequency (RF) technology concepts are outlined. Basic principles of mapping and shimming of transmission fields including RF power deposition considerations are presented. Explorations motivated by the safe operation of UHF-CMR even in the presence of conductive implants are described together with the physics, numerical simulations and experiments, all of which detailing antenna effects and RF heating induced by intracoronary stents at 7.0 T. Early applications of CMR at 7.0 T and their clinical implications for explorations into cardiovascular diseases are explored including assessment of cardiac function, myocardial tissue characterization, MR angiography of large and small vessels as well as heteronuclear MR of the heart and the skin. A concluding section ventures a glance beyond the horizon and explores future directions. The goal here is not to be comprehensive but to inspire the biomedical and diagnostic imaging communities to throw further weight behind the solution of the many remaining unsolved problems and technical obstacles of UHF-CMR with the goal to transfer MR physics driven methodological advancements into extra clinical value.

  11. The developing role of fetal magnetic resonance imaging in the diagnosis of congenital cardiac anomalies: A systematic review

    Directory of Open Access Journals (Sweden)

    Rohit S Loomba

    2011-01-01

    Full Text Available Advances in the fetal magnetic resonance imaging (MRI over the last few years have resulted in the exploring the use of fetal MRI to detect congenital cardiac anomalies. Early detection of congenital cardiac anomalies can help more appropriately manage the infant′s delivery and neonatal management. MRI offers anatomical and functional studies and is a safe adjunct that can help more fully understand a fetus′ cardiac anatomy. It is important for the obstetricians and pediatric cardiologists to be aware of the recent advancements in fetal MRI and it`s potential utility in diagnosing congenital cardiac anomalies.

  12. The developing role of fetal magnetic resonance imaging in the diagnosis of congenital cardiac anomalies: A systematic review

    International Nuclear Information System (INIS)

    Advances in the fetal magnetic resonance imaging (MRI) over the last few years have resulted in the exploring the use of fetal MRI to detect congenital cardiac anomalies. Early detection of congenital cardiac anomalies can help more appropriately manage the infant's delivery and neonatal management. MRI offers anatomical and functional studies and is a safe adjunct that can help more fully understand a fetus' cardiac anatomy. It is important for the obstetricians and pediatric cardiologists to be aware of the recent advancements in fetal MRI and it's potential utility in diagnosing congenital cardiac anomalies

  13. Cardiac remodeling following percutaneous mitral valve repair - initial results assessed by cardiovascular magnetic resonance imaging

    DEFF Research Database (Denmark)

    Radunski, U K; Franzen, O; Barmeyer, A;

    2014-01-01

    PURPOSE: Percutaneous mitral valve repair with the MitraClip device (Abbott Vascular, Redwood City, California, USA) is a novel therapeutic option in patients with mitral regurgitation. This study evaluated the feasibility of cardiac volume measurements by cardiovascular magnetic resonance imaging...... mitral valve repair results in reverse LV but not in RV or LA remodeling. KEY POINTS: • Volume measurements by cardiovascular magnetic resonance imaging are feasible following percutaneous mitral valve repair despite device-related artifacts.• A significant reduction of left ventricular volume was found...... end-systolic (48 [42 - 80] vs. 51 [40 - 81] ml/m(2); p = 0.48), and LA (87 [55 - 124] vs. 92 [48 - 137] ml/m(2); p = 0.20) volume indices between BL and FU. CONCLUSION: CMR enables the assessment of cardiac volumes in patients after MitraClip implantation. Our CMR findings indicate that percutaneous...

  14. Effects of deep sedation or general anesthesia on cardiac function in mice undergoing cardiovascular magnetic resonance

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    Kutschke William

    2009-05-01

    Full Text Available Abstract Background Genetically engineered mouse models of human cardiovascular disease provide an opportunity to understand critical pathophysiological mechanisms. Cardiovascular magnetic resonance (CMR provides precise reproducible assessment of cardiac structure and function, but, in contrast to echocardiography, requires that the animal be immobilized during image acquisition. General anesthetic regimens yield satisfactory images, but have the potential to significantly perturb cardiac function. The purpose of this study was to assess the effects of general anesthesia and a new deep sedation regimen, respectively, on cardiac function in mice as determined by CMR, and to compare them to results obtained in mildly sedated conscious mice by echocardiography. Results In 6 mildly sedated normal conscious mice assessed by echo, heart rate was 615 ± 25 min-1 (mean ± SE and left ventricular ejection fraction (LVEF was 0.94 ± 0.01. In the CMR studies of normal mice, heart rate was slightly lower during deep sedation with morphine/midazolam (583 ± 30 min-1, but the difference was not statistically significant. General anesthesia with 1% inhaled isoflurane significantly depressed heart rate (468 ± 7 min-1, p In mice with ischemic LV failure, ejection fraction measurements were comparable when performed during light sedation, deep sedation, and general anesthesia, respectively. Contrast-to-noise ratios were similar during deep sedation and during general anesthesia, indicating comparable image quality. Left ventricular mass measurements made by CMR during deep sedation were nearly identical to those made during general anesthesia (r2 = 0.99, mean absolute difference Conclusion In mice with normal cardiac function, CMR during deep sedation causes significantly less depression of heart rate and ejection fraction than imaging during general anesthesia with isoflurane. In mice with heart failure, the sedation/anesthesia regimen had no clear impact on

  15. Cardiac pathologies in female carriers of Duchenne muscular dystrophy assessed by cardiovascular magnetic resonance imaging

    International Nuclear Information System (INIS)

    Duchenne muscular dystrophy (DMD) is the most common and severe dystrophinopathy. DMD carriers rarely present with clinical symptoms, but may suffer from cardiac involvement. Because echocardiographic findings are inconsistent and cardiac magnetic resonance imaging (CMRI) data are limited, this study sought to investigate asymptomatic carriers for cardiac abnormalities using CMRI. Fifteen genetically confirmed DMD carriers (age, 32.3 ± 10.2 years) were prospectively examined on a 1.5T MR system. Cine, T2, and late-gadolinium-enhanced (LGE) images were acquired, and were evaluated in consensus by two experienced readers. Left ventricular (LV) parameters were analysed semiautomatically, normalized to BSA. Normalized LV end-diastolic volume was increased in 7 % (73.7 ± 16.8 ml/m2; range, 48-116 ml/m2) and normalized LV end-systolic volume in 20 % (31.5 ± 13.3 ml/m2; range, 15-74 ml/m2). EF was reduced in 33 % (58.4 ± 7.6 %; range, 37-69 %) and normalized LV myocardial mass in 80 % (40.5 ± 6.8 g/m2; range, 31-55 g/m2). In 80 %, regional myocardial thinning was detected in more than one segment. In 13 % and 40 %, apical-lateral accentuation of LV non-compaction was present. LGE was found in 60 % (midmyocardial inferolateral accentuation). Given the high frequency of cardiac pathologies detected by CMRI, regular cardiac risk assessment is advisable for DMD carriers. Besides clinical examination, CMRI is an excellent tool for this purpose. (orig.)

  16. Cardiac pathologies in female carriers of Duchenne muscular dystrophy assessed by cardiovascular magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Schelhorn, Juliane; Schemuth, Haemi; Nensa, Felix; Nassenstein, Kai; Forsting, Michael; Schlosser, Thomas [University Hospital Essen, Department of Diagnostic and Interventional Radiology and Neuroradiology, Essen (Germany); Schoenecker, Anne; Neudorf, Ulrich [University Hospital Essen, Department of Pediatric Cardiology, Essen (Germany); Schara, Ulrike [University Hospital Essen, Department of Pediatric Neurology, Essen (Germany)

    2015-10-15

    Duchenne muscular dystrophy (DMD) is the most common and severe dystrophinopathy. DMD carriers rarely present with clinical symptoms, but may suffer from cardiac involvement. Because echocardiographic findings are inconsistent and cardiac magnetic resonance imaging (CMRI) data are limited, this study sought to investigate asymptomatic carriers for cardiac abnormalities using CMRI. Fifteen genetically confirmed DMD carriers (age, 32.3 ± 10.2 years) were prospectively examined on a 1.5T MR system. Cine, T2, and late-gadolinium-enhanced (LGE) images were acquired, and were evaluated in consensus by two experienced readers. Left ventricular (LV) parameters were analysed semiautomatically, normalized to BSA. Normalized LV end-diastolic volume was increased in 7 % (73.7 ± 16.8 ml/m{sup 2}; range, 48-116 ml/m{sup 2}) and normalized LV end-systolic volume in 20 % (31.5 ± 13.3 ml/m{sup 2}; range, 15-74 ml/m{sup 2}). EF was reduced in 33 % (58.4 ± 7.6 %; range, 37-69 %) and normalized LV myocardial mass in 80 % (40.5 ± 6.8 g/m{sup 2}; range, 31-55 g/m{sup 2}). In 80 %, regional myocardial thinning was detected in more than one segment. In 13 % and 40 %, apical-lateral accentuation of LV non-compaction was present. LGE was found in 60 % (midmyocardial inferolateral accentuation). Given the high frequency of cardiac pathologies detected by CMRI, regular cardiac risk assessment is advisable for DMD carriers. Besides clinical examination, CMRI is an excellent tool for this purpose. (orig.)

  17. Structural and functional cardiac changes in myotonic dystrophy type 1: a cardiovascular magnetic resonance study

    Directory of Open Access Journals (Sweden)

    Hermans Mieke CE

    2012-07-01

    Full Text Available Abstract Background Myotonic dystrophy type 1 (MD1 is a neuromuscular disorder with potential involvement of the heart and increased risk of sudden death. Considering the importance of cardiomyopathy as a predictor of prognosis, we aimed to systematically evaluate and describe structural and functional cardiac alterations in patients with MD1. Methods Eighty MD1 patients underwent physical examination, electrocardiography (ECG, echocardiography and cardiovascular magnetic resonance (CMR. Blood samples were taken for determination of NT-proBNP plasma levels and CTG repeat length. Results Functional and structural abnormalities were detected in 35 patients (44%. Left ventricular systolic dysfunction was found in 20 cases, left ventricular dilatation in 7 patients, and left ventricular hypertrophy in 6 patients. Myocardial fibrosis was seen in 10 patients (12.5%. In general, patients had low left ventricular mass indexes. Right ventricular involvement was uncommon and only seen together with left ventricular abnormalities. Functional or structural cardiac involvement was associated with age (p = 0.04, male gender (p Conclusions CMR can be useful to detect early structural and functional myocardial abnormalities in patients with MD1. Myocardial involvement is strongly associated with conduction abnormalities, but a normal ECG does not exclude myocardial alterations. These findings lend support to the hypothesis that MD1 patients have a complex cardiac phenotype, including both myocardial and conduction system alteration.

  18. Myocardial Infarct Segmentation From Magnetic Resonance Images for Personalized Modeling of Cardiac Electrophysiology.

    Science.gov (United States)

    Ukwatta, Eranga; Arevalo, Hermenegild; Li, Kristina; Yuan, Jing; Qiu, Wu; Malamas, Peter; Wu, Katherine C; Trayanova, Natalia A; Vadakkumpadan, Fijoy

    2016-06-01

    Accurate representation of myocardial infarct geometry is crucial to patient-specific computational modeling of the heart in ischemic cardiomyopathy. We have developed a methodology for segmentation of left ventricular (LV) infarct from clinically acquired, two-dimensional (2D), late-gadolinium enhanced cardiac magnetic resonance (LGE-CMR) images, for personalized modeling of ventricular electrophysiology. The infarct segmentation was expressed as a continuous min-cut optimization problem, which was solved using its dual formulation, the continuous max-flow (CMF). The optimization objective comprised of a smoothness term, and a data term that quantified the similarity between image intensity histograms of segmented regions and those of a set of training images. A manual segmentation of the LV myocardium was used to initialize and constrain the developed method. The three-dimensional geometry of infarct was reconstructed from its segmentation using an implicit, shape-based interpolation method. The proposed methodology was extensively evaluated using metrics based on geometry, and outcomes of individualized electrophysiological simulations of cardiac dys(function). Several existing LV infarct segmentation approaches were implemented, and compared with the proposed method. Our results demonstrated that the CMF method was more accurate than the existing approaches in reproducing expert manual LV infarct segmentations, and in electrophysiological simulations. The infarct segmentation method we have developed and comprehensively evaluated in this study constitutes an important step in advancing clinical applications of personalized simulations of cardiac electrophysiology. PMID:26731693

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

    International Nuclear Information System (INIS)

    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∼0.95, p<0.05∼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)

  20. Cardiac sarcoidosis evaluated with gadolinium-enhanced magnetic resonance and contrast-enhanced 64-slice computed tomography.

    Science.gov (United States)

    Smedema, Jan-Peter; Truter, Rene; de Klerk, Petra A; Zaaiman, Leonie; White, Leonie; Doubell, Anton F

    2006-09-20

    Sarcoidosis is a multi-system granulomatous disorder of unknown etiology with symptomatic cardiac involvement in up to 7% of patients. The clinical features of sarcoid heart disease include congestive heart failure, arrhythmias, conduction disturbances, and sudden death. We evaluated the value of contrast-enhanced multi-detector computed tomography in delineating myocardial scar and granulomatous inflammation by comparing our findings with gadolinium magnetic resonance in a patient diagnosed with cardiac sarcoidosis. PMID:16257460

  1. Cardiac Sarcoidosis or Giant Cell Myocarditis? On Treatment Improvement of Fulminant Myocarditis as Demonstrated by Cardiovascular Magnetic Resonance Imaging

    Directory of Open Access Journals (Sweden)

    Hari Bogabathina

    2012-01-01

    Full Text Available Giant cell myocarditis, but not cardiac sarcoidosis, is known to cause fulminant myocarditis resulting in severe heart failure. However, giant cell myocarditis and cardiac sarcoidosis are pathologically similar, and attempts at pathological differentiation between the two remain difficult. We are presenting a case of fulminant myocarditis that has pathological features suggestive of cardiac sarcoidosis, but clinically mimicking giant cell myocarditis. This patient was treated with cyclosporine and prednisone and recovered well. This case we believe challenges our current understanding of these intertwined conditions. By obtaining a sense of severity of cardiac involvement via delayed hyperenhancement of cardiac magnetic resonance imaging, we were more inclined to treat this patient as giant cell myocarditis with cyclosporine. This resulted in excellent improvement of patient’s cardiac function as shown by delayed hyperenhancement images, early perfusion images, and SSFP videos.

  2. Cardiac metabolism during exercise in healthy volunteers measured by 31P magnetic resonance spectroscopy.

    Science.gov (United States)

    Conway, M A; Bristow, J D; Blackledge, M J; Rajagopalan, B; Radda, G K

    1991-01-01

    A technique was devised for individuals to exercise prone in a magnet during magnetic resonance spectroscopy of the heart and phosphorus-31 magnetic resonance spectra of the heart were obtained by the phase modulated rotating frame imaging technique in six healthy volunteers during steady state dynamic quadriceps exercise. During prone exercise heart rate, blood pressure, and total body oxygen consumption were measured at increasing loads and the results were compared with those during Bruce protocol treadmill exercise. During prone exercise with a 5 kg load the heart rate was similar and the systolic and diastolic blood pressures were higher than those during stage 1 of the Bruce protocol. The rate-pressure products were similar but the total body oxygen consumption was lower during prone exercise. There was no difference in the ratio of phosphocreatine to adenosine triphosphate during rest and exercise.Thus during exercise that produced a local cardiac stress equal to or greater than that during stage 1 of the Bruce protocol treadmill exercise, the energy requirements of the normal human myocardium were adequately supplied by oxidative phosphorylation. PMID:1993127

  3. Serum lipidomics meets cardiac magnetic resonance imaging: profiling of subjects at risk of dilated cardiomyopathy.

    Directory of Open Access Journals (Sweden)

    Marko Sysi-Aho

    Full Text Available Dilated cardiomyopathy (DCM, characterized by left ventricular dilatation and systolic dysfunction, constitutes a significant cause for heart failure, sudden cardiac death or need for heart transplantation. Lamin A/C gene (LMNA on chromosome 1p12 is the most significant disease gene causing DCM and has been reported to cause 7-9% of DCM leading to cardiac transplantation. We have previously performed cardiac magnetic resonance imaging (MRI to LMNA carriers to describe the early phenotype. Clinically, early recognition of subjects at risk of developing DCM would be important but is often difficult. Thus we have earlier used the MRI findings of these LMNA carriers for creating a model by which LMNA carriers could be identified from the controls at an asymptomatic stage. Some LMNA mutations may cause lipodystrophy. To characterize possible effects of LMNA mutations on lipid profile, we set out to apply global serum lipidomics using Ultra Performance Liquid Chromatography coupled to mass spectrometry in the same LMNA carriers, DCM patients without LMNA mutation and controls. All DCM patients, with or without LMNA mutation, differed from controls in regard to distinct serum lipidomic profile dominated by diminished odd-chain triglycerides and lipid ratios related to desaturation. Furthermore, we introduce a novel approach to identify associations between the molecular lipids from serum and the MR images from the LMNA carriers. The association analysis using dependency network and regression approaches also helped us to obtain novel insights into how the affected lipids might relate to cardiac shape and volume changes. Our study provides a framework for linking serum derived molecular markers not only with clinical endpoints, but also with the more subtle intermediate phenotypes, as derived from medical imaging, of potential pathophysiological relevance.

  4. Late gadolinium enhancement by magnetic resonance explains adverse cardiac events in individuals with ventricular arrhythmia

    International Nuclear Information System (INIS)

    Objective: To determine whether the presence of late gadolinium enhancement (LGE) by cardiovascular magnetic resonance (CMR) predict adverse cardiac events in patients with ventricular arrhythmia. Methods: We selected 74 consecutive patients with symptomatic ventricular arrhythmia (premature ventricular contractions and ventricular tachycardia) and left ventricular ejection fraction (LVEF) >55% sent to CMR for evaluation of structural heart disease previously undetected by other complementary methods. LGE, systolic function and volumes of both ventricles were analyzed. At follow-up was assessed a combined end point: hospitalization for ventricular arrhythmia, appropriate implantable cardioverter-defibrillator therapy and cardiac death. Results: During a median follow up of 575 days (interquartile range 24-1120 days) and by analyzing the population according to the presence (n=9, 12%) or not (n=65, 88%) LGE was observed that the group with positive Gd had lower LVEF (58% vs. 66% respectively, p=0.01) and larger volumes (EDV: 185 ml vs. 123 ml respectively, p=0.01 and ESV: 81 ml vs. 42 ml respectively, p=0.01) than the other group. Two (22%) patients in the LGE + group vs. one (4%) of those without LGE showed the combined endpoint (p=0.01) and when performing a logistic regression analysis it was found that the LGE is a predictor of adverse cardiac events analyzed (p=0.029). Conclusions: In this consecutive series of patients with ventricular arrhythmia we demonstrate a strong association between myocardial LGE and adverse cardiac events; this supports the hypothesis that myocardial fibrosis is an important arrhythmogenic substrate. In addition, almost all individuals without LGE were free of events during follow-up suggesting that it is possible to identify through the CMR low-risk individuals who can be treated conservatively. (authors)

  5. Age-related normal structural and functional ventricular values in cardiac function assessed by magnetic resonance

    International Nuclear Information System (INIS)

    The heart is subject to structural and functional changes with advancing age. However, the magnitude of cardiac age-dependent transformation has not been conclusively elucidated. This retrospective cardiac magnetic resonance (CMR) study included 183 subjects with normal structural and functional ventricular values. End systolic volume (ESV), end diastolic volume (EDV), and ejection fraction (EF) were obtained from the left and the right ventricle in breath-hold cine CMR. Patients were classified into four age groups (20–29, 30–49, 50–69, and ≥70 years) and cardiac measurements were compared using Pearson’s rank correlation over the four different groups. With advanced age a slight but significant decrease in ESV (r=−0.41 for both ventricles, P<0.001) and EDV (r=−0.39 for left ventricle, r=−0.35 for right ventricle, P<0.001) were observed associated with a significant increase in left (r=0.28, P<0.001) and right (r=0.27, P<0.01) ventricular EF reaching a maximal increase in EF of +8.4% (P<0.001) for the left and +6.1% (P<0.01) for the right ventricle in the oldest compared to the youngest patient group. Left ventricular myocardial mass significantly decreased over the four different age groups (P<0.05). The aging process is associated with significant changes in left and right ventricular EF, ESV and EDV in subjects with no cardiac functional and structural abnormalities. These findings underline the importance of using age adapted values as standard of reference when evaluating CMR studies

  6. Semi-automated scar detection in delayed enhanced cardiac magnetic resonance images

    Science.gov (United States)

    Morisi, Rita; Donini, Bruno; Lanconelli, Nico; Rosengarden, James; Morgan, John; Harden, Stephen; Curzen, Nick

    2015-06-01

    Late enhancement cardiac magnetic resonance images (MRI) has the ability to precisely delineate myocardial scars. We present a semi-automated method for detecting scars in cardiac MRI. This model has the potential to improve routine clinical practice since quantification is not currently offered due to time constraints. A first segmentation step was developed for extracting the target regions for potential scar and determining pre-candidate objects. Pattern recognition methods are then applied to the segmented images in order to detect the position of the myocardial scar. The database of late gadolinium enhancement (LE) cardiac MR images consists of 111 blocks of images acquired from 63 patients at the University Hospital Southampton NHS Foundation Trust (UK). At least one scar was present for each patient, and all the scars were manually annotated by an expert. A group of images (around one third of the entire set) was used for training the system which was subsequently tested on all the remaining images. Four different classifiers were trained (Support Vector Machine (SVM), k-nearest neighbor (KNN), Bayesian and feed-forward neural network) and their performance was evaluated by using Free response Receiver Operating Characteristic (FROC) analysis. Feature selection was implemented for analyzing the importance of the various features. The segmentation method proposed allowed the region affected by the scar to be extracted correctly in 96% of the blocks of images. The SVM was shown to be the best classifier for our task, and our system reached an overall sensitivity of 80% with less than 7 false positives per patient. The method we present provides an effective tool for detection of scars on cardiac MRI. This may be of value in clinical practice by permitting routine reporting of scar quantification.

  7. Magnetic resonance imaging in familial hypertrophic cardiomyopathy associated with abnormal thallium perfusion and cardiac enzymes

    International Nuclear Information System (INIS)

    Gated magnetic resonance imaging (MRI) was performed in 6 patients with familial hypertrophic cardiomyopathy associated with abnormal thallium perfusion, and 12 patients with ordinary hypertrophic cardiomyopathy. The patients with ordinary hypertrophic cardiomyopathy and abnormal thickening of the septal wall and normal left ventricular dimensions, while the patients with familial hypertrophic cardiomyopathy had focal wall thinning (usually involving the apical-septal wall) and dilated left ventricle in addition to hypertrophied heart. The quantitative measurement for cardiac dimensions using MRI was similar to that found on echocardiography in all cases. In addition, inhomogeneous signal intensities at left ventricular wall were observed in 3 cases of familial hypertrophic cardiomyopathy, which may suggest the existence of myocardial fibrosis. Gated MRI should be performed for early detection and follow-up of hypertrophic cardiomyopathy, since some patients will progress from hypertrophic cardiomyopathy to dilated cardiomyopathy. (author)

  8. Magnetic resonance imaging in familial hypertrophic cardiomyopathy associated with abnormal thallium perfusion and cardiac enzymes

    Energy Technology Data Exchange (ETDEWEB)

    Nishimura, Tsunehiko; Nagata, Seiki; Sakakibara, Hiroshi

    1988-05-01

    Gated magnetic resonance imaging (MRI) was performed in 6 patients with familial hypertrophic cardiomyopathy associated with abnormal thallium perfusion, and 12 patients with ordinary hypertrophic cardiomyopathy. The patients with ordinary hypertrophic cardiomyopathy and abnormal thickening of the septal wall and normal left ventricular dimensions, while the patients with familial hypertrophic cardiomyopathy had focal wall thinning (usually involving the apical-septal wall) and dilated left ventricle in addition to hypertrophied heart. The quantitative measurement for cardiac dimensions using MRI was similar to that found on echocardiography in all cases. In addition, inhomogeneous signal intensities at left ventricular wall were observed in 3 cases of familial hypertrophic cardiomyopathy, which may suggest the existence of myocardial fibrosis. Gated MRI should be performed for early detection and follow-up of hypertrophic cardiomyopathy, since some patients will progress from hypertrophic cardiomyopathy to dilated cardiomyopathy.

  9. The utility of magnetic resonance imaging in cardiac tissue regeneration trials.

    Science.gov (United States)

    Fuster, Valentin; Sanz, Javier; Viles-Gonzalez, Juan F; Rajagopalan, Sanjay

    2006-03-01

    The past decade has seen the emergence of paradigm shifts in concepts involving cardiovascular tissue regeneration, including the idea that adult stem cells originate in hematopoietic or bone marrow cells, the belief that even adult organs, such as the heart and nervous system, are capable of post-mitotic regeneration, and the concept of inherent plasticity in cells that have undergone limited lineage differentiation. There has consequently been a flurry of proposed regenerative strategies, and safety and limited efficacy data from both animal and limited human trials have been presented. The drive to push these advances from the bench to the bedside has created a unique environment where the therapeutic agents, delivery approaches, and methods of measuring efficacy (often imaging technology) are evolving practically in parallel. The encouraging results of recent cell-therapy trials should therefore be assessed cautiously and in consonance with an understanding of the advantages and limitations of delivery strategies and end points. Arguably, the use of imaging technologies to evaluate surrogate end points might help overcome the difficulty posed by large sample sizes required for hard end point trials in cardiovascular therapeutics. Cardiac magnetic resonance imaging is one of the most sensitive techniques available to assess spatial and temporal changes following local or systemic therapies, and the availability of a bevy of complementary techniques enables interrogation of physiology, morphology, and metabolism in one setting. We contend that cardiac magnetic resonance imaging is ideally suited to assess response to myocardial regeneration therapy and can be exploited to yield valuable insights into the mechanism of action of myocardial regeneration therapies. PMID:16501625

  10. Performance of automated software in the assessment of segmental left ventricular function in cardiac CT: Comparison with cardiac magnetic resonance

    International Nuclear Information System (INIS)

    To evaluate the accuracy, reliability and time saving potential of a novel cardiac CT (CCT)-based, automated software for the assessment of segmental left ventricular function compared to visual and manual quantitative assessment of CCT and cardiac magnetic resonance (CMR). Forty-seven patients with suspected or known coronary artery disease (CAD) were enrolled in the study. Wall thickening was calculated. Segmental LV wall motion was automatically calculated and shown as a colour-coded polar map. Processing time for each method was recorded. Mean wall thickness in both systolic and diastolic phases on polar map, CCT, and CMR was 9.2 ± 0.1 mm and 14.9 ± 0.2 mm, 8.9 ± 0.1 mm and 14.5 ± 0.1 mm, 8.3 ± 0.1 mm and 13.6 ± 0.1 mm, respectively. Mean wall thickening was 68.4 ± 1.5 %, 64.8 ± 1.4 % and 67.1 ± 1.4 %, respectively. Agreement for the assessment of LV wall motion between CCT, CMR and polar maps was good. Bland-Altman plots and ICC indicated good agreement between CCT, CMR and automated polar maps of the diastolic and systolic segmental wall thickness and thickening. The processing time using polar map was significantly decreased compared with CCT and CMR. Automated evaluation of segmental LV function with polar maps provides similar measurements to manual CCT and CMR evaluation, albeit with substantially reduced analysis time. (orig.)

  11. Performance of automated software in the assessment of segmental left ventricular function in cardiac CT: Comparison with cardiac magnetic resonance

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Rui [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Capital Medical University, Department of Radiology, Beijing Anzhen Hospital, Beijing (China); Meinel, Felix G. [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Ludwig-Maximilians-University Hospital, Institute for Clinical Radiology, Munich (Germany); Schoepf, U.J. [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Medical University of South Carolina, Division of Cardiology, Department of Medicine, Charleston, SC (United States); Canstein, Christian [Siemens Medical Solutions USA, Malvern, PA (United States); Spearman, James V. [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); De Cecco, Carlo N. [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); University of Rome ' ' Sapienza' ' , Departments of Radiological Sciences, Oncology and Pathology, Latina (Italy)

    2015-12-15

    To evaluate the accuracy, reliability and time saving potential of a novel cardiac CT (CCT)-based, automated software for the assessment of segmental left ventricular function compared to visual and manual quantitative assessment of CCT and cardiac magnetic resonance (CMR). Forty-seven patients with suspected or known coronary artery disease (CAD) were enrolled in the study. Wall thickening was calculated. Segmental LV wall motion was automatically calculated and shown as a colour-coded polar map. Processing time for each method was recorded. Mean wall thickness in both systolic and diastolic phases on polar map, CCT, and CMR was 9.2 ± 0.1 mm and 14.9 ± 0.2 mm, 8.9 ± 0.1 mm and 14.5 ± 0.1 mm, 8.3 ± 0.1 mm and 13.6 ± 0.1 mm, respectively. Mean wall thickening was 68.4 ± 1.5 %, 64.8 ± 1.4 % and 67.1 ± 1.4 %, respectively. Agreement for the assessment of LV wall motion between CCT, CMR and polar maps was good. Bland-Altman plots and ICC indicated good agreement between CCT, CMR and automated polar maps of the diastolic and systolic segmental wall thickness and thickening. The processing time using polar map was significantly decreased compared with CCT and CMR. Automated evaluation of segmental LV function with polar maps provides similar measurements to manual CCT and CMR evaluation, albeit with substantially reduced analysis time. (orig.)

  12. Cardiac effects of 3 months treatment of acromegaly evaluated by magnetic resonance imaging and B-type natriuretic peptides

    DEFF Research Database (Denmark)

    Andreassen, Mikkel; Faber, Jens Oscar; Kjær, Andreas;

    2010-01-01

    acromegaly is initiated. This was a three months prospective study investigating short-term cardiac effects of treatment in acromegalic patients. Cardiac function was evaluated by the gold standard method cardiac magnetic resonance imaging (CMRI) and circulating levels of B-type natriuretic peptides (BNP and......Long-term treatment of acromegaly prevents aggravation and reverses associated heart disease. A previous study has shown a temporary increase in serum levels of the N-terminal fraction of pro B-type natriuretic peptide (NT-proBNP) suggesting an initial decline in cardiac function when treatment of...... increase in EDVI, and increased levels of BNP and NT-proBNP suggesting an initial decrease in cardiac function....

  13. Prevention of Cardiomyopathy in Transfusion-Dependent Homozygous Thalassaemia Today and the Role of Cardiac Magnetic Resonance Imaging

    Directory of Open Access Journals (Sweden)

    Athanassios Aessopos

    2009-01-01

    Full Text Available Transfusion and iron chelation therapy revolutionised survival and reduced morbidity in patients with transfusion-dependent beta thalassaemia major. Despite these improvements, cardiac disease remained the most common cause of death in those patients. Recently the ability to determine the degree of cardiac iron overload, through cardiac magnetic resonance imaging (CMR has allowed more logical approaches to iron removal, particularly from the heart. The availability of two oral chelators, deferiprone and deferasirox has reduced the need for the injectable chelator deferrioxamine and an additional benefit has been that deferiprone has been shown to be more cardioprotective than deferrioxamine. This review on the prevention of cardiac disease makes recommendations on the chelation regime that would be desirable for patients according to their cardiac iron status as determined by CMR determined by CMR. It also discusses approaches to chelation management should CMR not be available.

  14. Cardiac magnetic resonance: Impact on diagnosis and management of patients with congenital cardiovascular disease

    International Nuclear Information System (INIS)

    Aim: To estimate the clinical impact of cardiac magnetic resonance (CMR) in patients with congenital cardiovascular disease (CCD). Materials and methods: Since 2003, 1.5 T CMR was used at our university hospital to evaluate morphology, cardiac kinetics, aortic and pulmonary flow, and vascular anatomy in patients with CCD. The present study considered a consecutive series of these patients from 2003 to 2006. A paediatric cardiologist judged our reports as expected or unexpected and, secondarily, as not reliable (level 0), describing findings already known (level 1), not changing therapy/suggested lifestyle (level 2), changing therapy/suggested lifestyle (level 3) or changing diagnosis (level 4). Results: CMR reports were judged to be expected in 187/214 (87%) and unexpected in 27/214 (13%). Less than 2% of CMRs were judged as levels 0 or 1, 66% as level 2, and 5% as level 4. During 2005-2006 the clinical impact improved toward higher impact levels (p < 0.001, chi-square test). Conclusions: In patients with CCD, more than one in 10 CMR reports were unexpected to cardiologists and over seven in 10 prompted a change of diagnosis or therapy.

  15. X-ray and magnetic resonance imaging fusion for cardiac resynchronization therapy.

    Science.gov (United States)

    Choi, Jinwoo; Radau, Perry; Xu, Robert; Wright, Graham A

    2016-07-01

    Cardiac Resynchronization Therapy (CRT) can effectively treat left ventricle (LV) driven Heart Failure (HF). However, 30% of the CRT recipients do not experience symptomatic benefit. Recent studies show that the CRT response rate can reach 95% when the LV pacing lead is placed at an optimal site at a region of maximal LV dyssynchrony and away from myocardial scars. Cardiac Magnetic Resonance (CMR) can identify the optimal site in three dimensions (3D). 3D CMR data can be registered to clinical standard x-ray fluoroscopy to achieve an optimal pacing of the LV. We have developed a 3D CMR to 2D x-ray image registration method for CRT procedures. We have employed the LV pacing lead on x-ray images and coronary sinus on MR data as landmarks. The registration method makes use of a guidewire simulation algorithm, edge based image registration technique and x-ray C-arm tracking to register the coronary sinus and pacing lead landmarks. PMID:27025953

  16. Echocardiography to magnetic resonance image registration for use in image-guided cardiac catheterization procedures

    International Nuclear Information System (INIS)

    We present a robust method to register three-dimensional echocardiography (echo) images to magnetic resonance images (MRI) based on anatomical features, which is designed to be used in the registration pipeline for overlaying MRI-derived roadmaps onto two-dimensional live x-ray images during cardiac catheterization procedures. The features used in image registration are the endocardial surface of the left ventricle and the centre line of the descending aorta. The MR-derived left ventricle surface is generated using a fully automated algorithm, and the echo-derived left ventricle surface is produced using a semi-automatic segmentation method provided by the QLab software (Philips Healthcare) that it is routinely used in clinical practice. We test our method on data from six volunteers and four patients. We validated registration accuracy using two methods: the first calculated a root mean square distance error using expert identified anatomical landmarks, and the second method used catheters as landmarks in two clinical electrophysiology procedures. Results show a mean error of 4.1 mm, which is acceptable for our clinical application, and no failed registrations were observed. In addition, our algorithm works on clinical data, is fast and only requires a small amount of manual input, and so it is applicable for use during cardiac catheterization procedures.

  17. Cine magnetic resonance imaging for evaluation of cardiac structure and flow dynamics in congenital heart disease

    International Nuclear Information System (INIS)

    Cine magnetic resonance imaging (Cine MRI) was performed in 20 patients aged 19 days to 13 years (mean 4.0 years), who had congenital heart disease confirmed at echocardiography or angiography. Prior to cine MRI, gated MRI was performed to evaluate for cardiac structure. Cine MRI was demonstrated by fast low fip angle shot imaging technique with a 30deg flip angle, 15 msec echo time, 30-40 msec pulse repetition time, and 128 x 128 acquisition matrix. Abnormalities of cardiac structure were extremely well defined in all patients by gated MRI. Intracardiac or intravascular blood flow were visualized in 17 (85%) of 20 patients by cine MRI. Left to right shunt flow through ventricular septal defect, atrial septal defect, and endocardial cushion defect were visualized with low signal intensity area. Low intensity jets flow through the site of re-coarctation of the aorta were also visualized. However, the good recording of cine MRI was not obtained because of artifacts in 3 of 20 patients (15%) who had severe congestive heart failure or respiratory arrhythmia. Gated MRI provides excellent visualization of fine structure, and cine MRI can provide high spatial resolution imaging of flow dynamic in a variety of congenital heart disease, noninvasively. (author)

  18. Cardiac resynchronization therapy guided by late gadolinium-enhancement cardiovascular magnetic resonance

    Directory of Open Access Journals (Sweden)

    Smith Russell EA

    2011-06-01

    Full Text Available Abstract Background Myocardial scarring at the LV pacing site leads to incomplete resynchronization and a suboptimal symptomatic response to CRT. We sought to determine whether the use of late gadolinium cardiovascular magnetic resonance (LGE-CMR to guide left ventricular (LV lead deployment influences the long-term outcome of cardiac resynchronization therapy (CRT. Methods 559 patients with heart failure (age 70.4 ± 10.7 yrs [mean ± SD] due to ischemic or non-ischemic cardiomyopathy underwent CRT. Implantations were either guided (+CMR or not guided (-CMR by LGE-CMR prior to implantation. Fluoroscopy and LGE-CMR were used to localize the LV lead tip and and myocardial scarring retrospectively. Clinical events were assessed in three groups: +CMR and pacing scar (+CMR+S; CMR and not pacing scar (+CMR-S, and; LV pacing not guided by CMR (-CMR. Results Over a maximum follow-up of 9.1 yrs, +CMR+S had the highest risk of cardiovascular death (HR: 6.34, cardiovascular death or hospitalizations for heart failure (HR: 5.57 and death from any cause or hospitalizations for major adverse cardiovascular events (HR: 4.74 (all P Conclusions Compared with a conventional implantation approach, the use of LGE-CMR to guide LV lead deployment away from scarred myocardium results in a better clinical outcome after CRT. Pacing scarred myocardium was associated with the worst outcome, in terms of both pump failure and sudden cardiac death.

  19. Optimized protocols for cardiac magnetic resonance imaging in patients with thoracic metallic implants

    Energy Technology Data Exchange (ETDEWEB)

    Olivieri, Laura J.; Ratnayaka, Kanishka [Children' s National Health System, Division of Cardiology, Washington, DC (United States); National Institutes of Health, National Heart, Lung and Blood Institute, Bethesda, MD (United States); Cross, Russell R.; O' Brien, Kendall E. [Children' s National Health System, Division of Cardiology, Washington, DC (United States); Hansen, Michael S. [National Institutes of Health, National Heart, Lung and Blood Institute, Bethesda, MD (United States)

    2015-09-15

    Cardiac magnetic resonance (MR) imaging is a valuable tool in congenital heart disease; however patients frequently have metal devices in the chest from the treatment of their disease that complicate imaging. Methods are needed to improve imaging around metal implants near the heart. Basic sequence parameter manipulations have the potential to minimize artifact while limiting effects on image resolution and quality. Our objective was to design cine and static cardiac imaging sequences to minimize metal artifact while maintaining image quality. Using systematic variation of standard imaging parameters on a fluid-filled phantom containing commonly used metal cardiac devices, we developed optimized sequences for steady-state free precession (SSFP), gradient recalled echo (GRE) cine imaging, and turbo spin-echo (TSE) black-blood imaging. We imaged 17 consecutive patients undergoing routine cardiac MR with 25 metal implants of various origins using both standard and optimized imaging protocols for a given slice position. We rated images for quality and metal artifact size by measuring metal artifact in two orthogonal planes within the image. All metal artifacts were reduced with optimized imaging. The average metal artifact reduction for the optimized SSFP cine was 1.5+/-1.8 mm, and for the optimized GRE cine the reduction was 4.6+/-4.5 mm (P < 0.05). Quality ratings favored the optimized GRE cine. Similarly, the average metal artifact reduction for the optimized TSE images was 1.6+/-1.7 mm (P < 0.05), and quality ratings favored the optimized TSE imaging. Imaging sequences tailored to minimize metal artifact are easily created by modifying basic sequence parameters, and images are superior to standard imaging sequences in both quality and artifact size. Specifically, for optimized cine imaging a GRE sequence should be used with settings that favor short echo time, i.e. flow compensation off, weak asymmetrical echo and a relatively high receiver bandwidth. For static

  20. Optimized protocols for cardiac magnetic resonance imaging in patients with thoracic metallic implants

    International Nuclear Information System (INIS)

    Cardiac magnetic resonance (MR) imaging is a valuable tool in congenital heart disease; however patients frequently have metal devices in the chest from the treatment of their disease that complicate imaging. Methods are needed to improve imaging around metal implants near the heart. Basic sequence parameter manipulations have the potential to minimize artifact while limiting effects on image resolution and quality. Our objective was to design cine and static cardiac imaging sequences to minimize metal artifact while maintaining image quality. Using systematic variation of standard imaging parameters on a fluid-filled phantom containing commonly used metal cardiac devices, we developed optimized sequences for steady-state free precession (SSFP), gradient recalled echo (GRE) cine imaging, and turbo spin-echo (TSE) black-blood imaging. We imaged 17 consecutive patients undergoing routine cardiac MR with 25 metal implants of various origins using both standard and optimized imaging protocols for a given slice position. We rated images for quality and metal artifact size by measuring metal artifact in two orthogonal planes within the image. All metal artifacts were reduced with optimized imaging. The average metal artifact reduction for the optimized SSFP cine was 1.5+/-1.8 mm, and for the optimized GRE cine the reduction was 4.6+/-4.5 mm (P < 0.05). Quality ratings favored the optimized GRE cine. Similarly, the average metal artifact reduction for the optimized TSE images was 1.6+/-1.7 mm (P < 0.05), and quality ratings favored the optimized TSE imaging. Imaging sequences tailored to minimize metal artifact are easily created by modifying basic sequence parameters, and images are superior to standard imaging sequences in both quality and artifact size. Specifically, for optimized cine imaging a GRE sequence should be used with settings that favor short echo time, i.e. flow compensation off, weak asymmetrical echo and a relatively high receiver bandwidth. For static

  1. Cardiac remodeling following percutaneous mitral valve repair. Initial results assessed by cardiovascular magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Radunski, U.K [University Heart Center, Hamburg (Germany). Cardiology; Franzen, O. [Rigshospitalet, Copenhagen (Denmark). Cardiology; Barmeyer, A. [Klinikum Dortmund (Germany). Kardiologie; and others

    2014-10-15

    Percutaneous mitral valve repair with the MitraClip device (Abbott Vascular, Redwood City, California, USA) is a novel therapeutic option in patients with mitral regurgitation. This study evaluated the feasibility of cardiac volume measurements by cardiovascular magnetic resonance imaging (CMR) to assess reverse myocardial remodeling in patients after MitraClip implantation. 12 patients underwent CMR at baseline (BL) before and at 6 months follow-up (FU) after MitraClip implantation. Cine-CMR was performed in short- and long-axes for the assessment of left ventricular (LV), right ventricular (RV) and left atrial (LA) volumes. Assessment of endocardial contours was not compromised by the device-related artifact. No significant differences in observer variances were observed for LV, RV and LA volume measurements between BL and FU. LV end-diastolic (median 127 [IQR 96-150] vs. 112 [86-150] ml/m{sup 2}; p=0.03) and LV end-systolic (82 [54-91] vs. 69 [48-99] ml/m{sup 2}; p=0.03) volume indices decreased significantly from BL to FU. No significant differences were found for RV end-diastolic (94 [75-103] vs. 99 [77-123] ml/m{sup 2}; p=0.91), RV end-systolic (48 [42-80] vs. 51 [40-81] ml/m{sup 2}; p=0.48), and LA (87 [55-124] vs. 92 [48-137]R ml/m{sup 2}; p=0.20) volume indices between BL and FU. CMR enables the assessment of cardiac volumes in patients after MitraClip implantation. Our CMR findings indicate that percutaneous mitral valve repair results in reverse LV but not in RV or LA remodeling.

  2. Visualization of a Small Ventricular Septal Defect at First-pass Contrast-enhanced Cardiac Magnetic Resonance Imaging

    Directory of Open Access Journals (Sweden)

    Francesco Secchi

    2013-01-01

    Full Text Available Ventricular septal defect (VSD is a congenital heart disease that accounts for up to 40% of all congenital cardiac malformations. VSD is a connection between right and left ventricle, through the ventricular septum. Echocardiography and magnetic resonance imaging (MRI help identify this entity. This case presents a 12-year-old male diagnosed with a small muscular apical VSD of 3 mm in diameter, at echocardiography. Cardiac MRI using first-pass perfusion sequence, combining the right plane of acquisition with a short bolus of contrast material, clearly confirmed the presence of VSD.

  3. Sodium nuclear magnetic resonance imaging of acute cardiac rejection in heterotopic heart transplantation

    International Nuclear Information System (INIS)

    Nuclear magnetic resonance (NMR) imagings have been applied to the observation of tissue sodium-23 in myocardium undergoing cardiac rejection. Six canine donor hearts were heterotopically transplanted in the recipient's chest cavity. The dogs were then killed and sodium-23 image of the excised donor hearts were obtained using a high field NMR imaging system (1.5 Tesla, Magnetom). Proton NMR imaging was also performed and T1, T2 relaxation times were calculated. Subsequently, these data were correlated with pathologic findings such as mild, moderate and severe rejection. The correlation coefficients between rejection score, and T1, T2 times and sodium NMR signal intensity were 0.79, 0.70 and 0.80, respectively. The moderate or severe rejected myocardium were clearly visible as areas of increased sodium NMR signal. These data suggested that increase of sodium may be mainly caused by the myocardial cellular necrosis. Sodium NMR will allow us to evaluate the location and extent of rejected myocardium undergoing heart transplantation. (author)

  4. The Use of Cardiac Magnetic Resonance Imaging in the Diagnostic Workup and Treatment of Atrial Fibrillation

    Directory of Open Access Journals (Sweden)

    Peter Haemers

    2012-01-01

    Full Text Available Atrial fibrillation (AF is the most common cardiac arrhythmia and imposes a huge clinical and economic burden. AF is correlated with an increased morbidity and mortality, mainly due to stroke and heart failure. Cardiovascular imaging modalities, including echocardiography, computed tomography (CT, and cardiovascular magnetic resonance (CMR, play a central role in the workup and treatment of AF. One of the major advantages of CMR is the high contrast to noise ratio combined with good spatial and temporal resolution, without any radiation burden. This allows a detailed assessment of the structure and function of the left atrium (LA. Of particular interest is the ability to visualize the extent of LA wall injury. We provide a focused review of the value of CMR in identifying the underlying pathophysiological mechanisms of AF, its role in stroke prevention and in the guidance of radiofrequency catheter ablation. CMR is a promising technique that could add valuable information for therapeutic decision making in specific subpopulations with AF.

  5. Three-dimensional magnetic resonance imaging overlay to assist with percutaneous transhepatic access at the time of cardiac catheterization

    International Nuclear Information System (INIS)

    Multimodality image overlay is increasingly used for complex interventional procedures in the cardiac catheterization lab. We report a case in which three-dimensional magnetic resonance imaging (3D MRI) overlay onto live fluoroscopic imaging was utilized to safely obtain transhepatic access in a 12-year-old patient with prune belly syndrome, complex and distorted abdominal anatomy, and a vascular mass within the liver

  6. Moderate intensity supine exercise causes decreased cardiac volumes and increased outer volume variations: a cardiovascular magnetic resonance study

    DEFF Research Database (Denmark)

    Steding-Ehrenborg, Katarina; Jablonowski, Robert; Arvidsson, Per M;

    2013-01-01

    The effects on left and right ventricular (LV, RV) volumes during physical exercise remains controversial. Furthermore, no previous study has investigated the effects of exercise on longitudinal contribution to stroke volume (SV) and the outer volume variation of the heart. The aim of this study ...... was to determine if LV, RV and total heart volumes (THV) as well as cardiac pumping mechanisms change during physical exercise compared to rest using cardiovascular magnetic resonance (CMR)....

  7. Three-dimensional magnetic resonance imaging overlay to assist with percutaneous transhepatic access at the time of cardiac catheterization

    Directory of Open Access Journals (Sweden)

    Wendy Whiteside

    2015-01-01

    Full Text Available Multimodality image overlay is increasingly used for complex interventional procedures in the cardiac catheterization lab. We report a case in which three-dimensional magnetic resonance imaging (3D MRI overlay onto live fluoroscopic imaging was utilized to safely obtain transhepatic access in a 12-year-old patient with prune belly syndrome, complex and distorted abdominal anatomy, and a vascular mass within the liver.

  8. Magnetic Resonance Elastography as a Method for the Assessment of Effective Myocardial Stiffness throughout the Cardiac Cycle

    OpenAIRE

    Kolipaka, Arunark; Araoz, Philip A; McGee, Kiaran P.; Manduca, Armando; Ehman, Richard L.

    2010-01-01

    Magnetic resonance elastography (MRE) is a noninvasive technique in which images of externally generated waves propagating in tissue are used to measure stiffness. The first aim is to determine, from a range of driver configurations the optimal driver for the purpose of generating waves within the heart in vivo. The second aim is to quantify the shear stiffness of normal myocardium throughout the cardiac cycle using MRE and to compare MRE stiffness to left ventricular (LV) chamber pressure in...

  9. Angiographic correlations of patients with small vessel disease diagnosed by adenosine-stress cardiac magnetic resonance imaging

    OpenAIRE

    Scheck Roland; Hoefling Berthold; Ali Eman; Klos Markus; Pilz Guenter; Bernhardt Peter

    2008-01-01

    Abstract Cardiac magnetic resonance imaging (CMR) with adenosine-stress myocardial perfusion is gaining importance for the detection and quantification of coronary artery disease (CAD). However, there is little knowledge about patients with CMR-detected ischemia, but having no relevant stenosis as seen on coronary angiography (CA). The aims of our study were to characterize these patients by CMR and CA and evaluate correlations and potential reasons for the ischemic findings. 73 patients with...

  10. Cardiac Magnetic Resonance Imaging Findings in a Patient with Ebstein’s Anomaly and Left Ventricular Dysfunction

    OpenAIRE

    Nasim Naderi; Ahmad Amin; Hamidreza Pouraliakbar

    2013-01-01

    Ebstein anomaly is characterized by apical displacement of the septal and posterior tricuspid valve leaflets, leading to atrialization of the right ventricle and could be diagnosed in a routine transthoracic echocardiography exam. We reported a young man with right sided heart failure symptoms who was found to have biventricular failure with suspected apical displacement of septal leaflet of tricuspid valve. For better evaluation, cardiac magnetic resonance imaging (CMR) was performed and nic...

  11. Acute Cardiac Impairment Associated With Concurrent Chemoradiotherapy for Esophageal Cancer: Magnetic Resonance Evaluation

    International Nuclear Information System (INIS)

    Purpose: To evaluate acute cardiac effects of concurrent chemoradiotherapy (CCRT) for esophageal cancer. Methods and Materials: This prospective study was approved by the institutional review board, and written informed consent was obtained from all participants. The left ventricular function (LVF) of 31 patients with esophageal cancer who received cisplatin and 5-fluorouracil–based CCRT was evaluated using cardiac cine magnetic resonance imaging. The patients were classified into two groups according to mean LV dose. The parameters related to LVF were compared between before and during (40 Gy) or between before and after CCRT using a Wilcoxon matched-pairs single rank test, and parameter ratios (during/before CCRT, after/before CCRT) were also compared between the groups with a t test. Data were expressed as mean ± SE. Results: In the low LV-dose group (n = 10; mean LV dose 2), LV stroke volume index (38.6 ± 1.56 vs. 29.9 ± 1.60 mL/m2), and LV ejection fraction (56.9% ± 1.79% vs. 52.8% ± 1.15%) decreased significantly (p < 0.05) after CCRT. Heart rate increased significantly (before vs. during vs. after CCRT; 66.8 ± 3.05 vs. 72.4 ± 4.04 vs. 85.4 ± 3.75 beats per minute, p < 0.01). Left ventricle wall motion decreased significantly (p < 0.05) in segments 8 (before vs. during vs. after CCRT; 6.64 ± 0.54 vs. 4.78 ± 0.43 vs. 4.79 ± 0.50 mm), 9 (6.88 ± 0.45 vs. 5.04 ± 0.38 vs. 5.27 ± 0.47 mm), and 10 (9.22 ± 0.48 vs. 8.08 ± 0.34 vs. 8.19 ± 0.56 mm). The parameter ratios of LV end-diastolic volume index, stroke volume index, wall motion in segment 9, and heart rate showed significant difference (p < 0.05) after CCRT between the groups. Conclusions: Concurrent chemoradiotherapy for esophageal cancer impairs LVF from an early treatment stage. This impairment is prominent in patients with high LV dose.

  12. Diffuse myocardial fibrosis following tetralogy of Fallot repair: a T1 mapping cardiac magnetic resonance study

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    Kozak, Marcelo F.; Yoo, Shi-Joon; Seed, Mike; Grosse-Wortmann, Lars [The Hospital for Sick Children, University of Toronto, Labatt Family Heart Centre in the Department of Paediatrics and Department of Diagnostic Imaging, Toronto (Canada); Redington, Andrew [The Hospital for Sick Children, University of Toronto, Labatt Family Heart Centre in the Department of Paediatrics, Toronto (Canada); Greiser, Andreas [Siemens AG Healthcare Sector, Erlangen (Germany)

    2014-04-15

    Adverse ventricular remodeling after tetralogy of Fallot (TOF) repair is associated with diffuse myocardial fibrosis. The goal of this study was to measure post-contrast myocardial T1 in pediatric patients after TOF repair as surrogates of myocardial fibrosis. Children after TOF repair who underwent cardiac magnetic resonance imaging with T1 mapping using the modified look-locker inversion recovery (MOLLI) sequence were included. In addition to routine volumetric and flow data, we measured post-contrast T1 values of the basal interventricular septum, the left ventricular (LV) lateral wall, and the inferior and anterior walls of the right ventricle (RV). Results were compared to data from age-matched healthy controls. The scans of 18 children who had undergone TOF repair and 12 healthy children were included. Post-contrast T1 values of the left ventricular lateral wall (443 ± 54 vs. 510 ± 77 ms, P = 0.0168) and of the right ventricular anterior wall (333 ± 62 vs. 392 ± 72 ms, P = 0.0423) were significantly shorter in children with TOF repair than in controls, suggesting a higher degree of fibrosis. In children with TOF repair, but not in controls, post-contrast T1 values were shorter in the right ventricle than the left ventricle and shorter in the anterior wall of the right ventricle than in the inferior segments. In the TOF group, post-contrast T1 values of the RV anterior wall correlated with the RV end-systolic volume indexed to body surface area (r = 0.54; r{sup 2} = 0.30; P = 0.0238). In children who underwent tetralogy of Fallot repair the myocardium of both ventricles appears to bear an abnormally high fibrosis burden. (orig.)

  13. Unrecognized Myocardial Infarction Assessed by Cardiac Magnetic Resonance Imaging--Prognostic Implications.

    Directory of Open Access Journals (Sweden)

    Anna M Nordenskjöld

    Full Text Available Clinically unrecognized myocardial infarctions (UMI are not uncommon and may be associated with adverse outcome. The aims of this study were to determine the prognostic implication of UMI in patients with stable suspected coronary artery disease (CAD and to investigate the associations of UMI with the presence of CAD.In total 235 patients late gadolinium enhancement cardiovascular magnetic resonance (LGE-CMR imaging and coronary angiography were performed. For each patient with UMI, the stenosis grade of the coronary branch supplying the infarcted area was determined. UMIs were present in 25% of the patients and 67% of the UMIs were located in an area supplied by a coronary artery with a stenosis grade ≥70%. In an age- and gender-adjusted model, UMI independently predicted the primary endpoint (composite of death, myocardial infarction, resuscitated cardiac arrest, hospitalization for unstable angina pectoris or heart failure within 2 years of follow-up with an odds ratio of 2.9; 95% confidence interval 1.1-7.9. However, this association was abrogated after adjustment for age and presence of significant coronary disease. There was no difference in the primary endpoint rates between UMI patients with or without a significant stenosis in the corresponding coronary artery.The presence of UMI was associated with a threefold increased risk of adverse events during follow up. However, the difference was no longer statistically significant after adjustments for age and severity of CAD. Thus, the results do not support that patients with suspicion of CAD should be routinely investigated by LGE-CMR for UMI. However, coronary angiography should be considered in patients with UMI detected by LGE-CMR.ClinicalTrials.gov NTC01257282.

  14. Cardiac magnetic resonance imaging for myocardial perfusion and diastolic function-reference control values for women.

    Science.gov (United States)

    Bakir, May; Wei, Janet; Nelson, Michael D; Mehta, Puja K; Haftbaradaran, Afsaneh; Jones, Erika; Gill, Edward; Sharif, Behzad; Slomka, Piotr J; Li, Debiao; Shufelt, Chrisandra L; Minissian, Margo; Berman, Daniel S; Bairey Merz, C Noel; Thomson, Louise E J

    2016-02-01

    Angina, heart failure with preserved ejection fraction (HFpEF) and coronary microvascular dysfunction (CMD) in the absence of obstructive coronary artery disease (CAD) are more common in women and are associated with adverse cardiovascular prognosis. Cardiac magnetic resonance imaging (CMRI) is established for assessment of left ventricular (LV) morphology and systolic function and is increasingly used to assess myocardial perfusion and diastolic function. Indeed, stress CMRI allows measurement of myocardial perfusion reserve index (MPRI) using semi-quantitative techniques, and quantification of LV volumetric filling patterns provides valuable insight into LV diastolic function. The utility of these two techniques remains limited, because reference control values for MPRI and LV diastolic function in asymptomatic middle-aged, women have not previously been established. To address this limitation, we recruited twenty women, without clinical cardiovascular disease or cardiovascular risk factors, with normal maximal Bruce protocol exercise treadmill testing. Subjects underwent CMRI (1.5 tesla) using a standardized protocol of adenosine stress and rest perfusion and LV cinematic imaging. Commercially available with automated CMRI segmentation was used for calculation of MPRI, LV filling profiles, and ejection fraction. Mean age was 54±9 years and mean body mass index was 25±4 kg/m(3). The exercise treadmill testing results demonstrated a normotensive group with normal functional capacity and hemodynamic response. We report reference control values for semi-quantitative MPRI as well as measures of LV systolic and diastolic function including ejection fraction, stroke volume, peak filling rate (PFR), PFR adjusted for end-diastolic volume (EDV) and stroke volume, time to PFR, and EDV index. The data herein provide reference values for MPRI and diastolic function in a cohort of healthy, middle-aged of women. These reference values may be used for comparison with a

  15. Aerobic Training after Myocardial Infarction: Remodeling Evaluated by Cardiac Magnetic Resonance

    Directory of Open Access Journals (Sweden)

    Nataly Lino Izeli

    2016-04-01

    Full Text Available Abstract Background: Numerous studies show the benefits of exercise training after myocardial infarction (MI. Nevertheless, the effects on function and remodeling are still controversial. Objectives: To evaluate, in patients after (MI, the effects of aerobic exercise of moderate intensity on ventricular remodeling by cardiac magnetic resonance imaging (CMR. Methods: 26 male patients, 52.9 ± 7.9 years, after a first MI, were assigned to groups: trained group (TG, 18; and control group (CG, 8. The TG performed supervised aerobic exercise on treadmill twice a week, and unsupervised sessions on 2 additional days per week, for at least 3 months. Laboratory tests, anthropometric measurements, resting heart rate (HR, exercise test, and CMR were conducted at baseline and follow-up. Results: The TG showed a 10.8% reduction in fasting blood glucose (p = 0.01, and a 7.3-bpm reduction in resting HR in both sitting and supine positions (p < 0.0001. There was an increase in oxygen uptake only in the TG (35.4 ± 8.1 to 49.1 ± 9.6 mL/kg/min, p < 0.0001. There was a statistically significant decrease in the TG left ventricular mass (LVmass (128.7 ± 38.9 to 117.2 ± 27.2 g, p = 0.0032. There were no statistically significant changes in the values of left ventricular end-diastolic volume (LVEDV and ejection fraction in the groups. The LVmass/EDV ratio demonstrated a statistically significant positive remodeling in the TG (p = 0.015. Conclusions: Aerobic exercise of moderate intensity improved physical capacity and other cardiovascular variables. A positive remodeling was identified in the TG, where a left ventricular diastolic dimension increase was associated with LVmass reduction.

  16. Cardiac magnetic resonance imaging for myocardial perfusion and diastolic function—reference control values for women

    Science.gov (United States)

    Bakir, May; Wei, Janet; Nelson, Michael D.; Mehta, Puja K.; Haftbaradaran, Afsaneh; Jones, Erika; Gill, Edward; Sharif, Behzad; Slomka, Piotr J.; Li, Debiao; Shufelt, Chrisandra L.; Minissian, Margo; Berman, Daniel S.; Bairey Merz, C. Noel

    2016-01-01

    Angina, heart failure with preserved ejection fraction (HFpEF) and coronary microvascular dysfunction (CMD) in the absence of obstructive coronary artery disease (CAD) are more common in women and are associated with adverse cardiovascular prognosis. Cardiac magnetic resonance imaging (CMRI) is established for assessment of left ventricular (LV) morphology and systolic function and is increasingly used to assess myocardial perfusion and diastolic function. Indeed, stress CMRI allows measurement of myocardial perfusion reserve index (MPRI) using semi-quantitative techniques, and quantification of LV volumetric filling patterns provides valuable insight into LV diastolic function. The utility of these two techniques remains limited, because reference control values for MPRI and LV diastolic function in asymptomatic middle-aged, women have not previously been established. To address this limitation, we recruited twenty women, without clinical cardiovascular disease or cardiovascular risk factors, with normal maximal Bruce protocol exercise treadmill testing. Subjects underwent CMRI (1.5 tesla) using a standardized protocol of adenosine stress and rest perfusion and LV cinematic imaging. Commercially available with automated CMRI segmentation was used for calculation of MPRI, LV filling profiles, and ejection fraction. Mean age was 54±9 years and mean body mass index was 25±4 kg/m3. The exercise treadmill testing results demonstrated a normotensive group with normal functional capacity and hemodynamic response. We report reference control values for semi-quantitative MPRI as well as measures of LV systolic and diastolic function including ejection fraction, stroke volume, peak filling rate (PFR), PFR adjusted for end-diastolic volume (EDV) and stroke volume, time to PFR, and EDV index. The data herein provide reference values for MPRI and diastolic function in a cohort of healthy, middle-aged of women. These reference values may be used for comparison with a variety

  17. Diffuse myocardial fibrosis following tetralogy of Fallot repair: a T1 mapping cardiac magnetic resonance study

    International Nuclear Information System (INIS)

    Adverse ventricular remodeling after tetralogy of Fallot (TOF) repair is associated with diffuse myocardial fibrosis. The goal of this study was to measure post-contrast myocardial T1 in pediatric patients after TOF repair as surrogates of myocardial fibrosis. Children after TOF repair who underwent cardiac magnetic resonance imaging with T1 mapping using the modified look-locker inversion recovery (MOLLI) sequence were included. In addition to routine volumetric and flow data, we measured post-contrast T1 values of the basal interventricular septum, the left ventricular (LV) lateral wall, and the inferior and anterior walls of the right ventricle (RV). Results were compared to data from age-matched healthy controls. The scans of 18 children who had undergone TOF repair and 12 healthy children were included. Post-contrast T1 values of the left ventricular lateral wall (443 ± 54 vs. 510 ± 77 ms, P = 0.0168) and of the right ventricular anterior wall (333 ± 62 vs. 392 ± 72 ms, P = 0.0423) were significantly shorter in children with TOF repair than in controls, suggesting a higher degree of fibrosis. In children with TOF repair, but not in controls, post-contrast T1 values were shorter in the right ventricle than the left ventricle and shorter in the anterior wall of the right ventricle than in the inferior segments. In the TOF group, post-contrast T1 values of the RV anterior wall correlated with the RV end-systolic volume indexed to body surface area (r = 0.54; r2 = 0.30; P = 0.0238). In children who underwent tetralogy of Fallot repair the myocardium of both ventricles appears to bear an abnormally high fibrosis burden. (orig.)

  18. Prognostic significance of late gadolinium enhancement quantification in cardiac magnetic resonance imaging of hypertrophic cardiomyopathy with systolic dysfunction.

    Science.gov (United States)

    Funada, Akira; Kanzaki, Hideaki; Noguchi, Teruo; Morita, Yoshiaki; Sugano, Yasuo; Ohara, Takahiro; Hasegawa, Takuya; Hashimura, Hiromi; Ishibashi-Ueda, Hatsue; Kitakaze, Masafumi; Yasuda, Satoshi; Ogawa, Hisao; Anzai, Toshihisa

    2016-05-01

    Hypertrophic cardiomyopathy (HCM) with systolic dysfunction carries a poor prognosis. Although late gadolinium enhancement (LGE) on cardiac magnetic resonance is associated with adverse cardiac events in HCM and is inversely related to left ventricular ejection fraction (LVEF), it is unknown whether LGE or LVEF more accurately predicts adverse cardiac events in HCM with systolic dysfunction. We retrospectively assessed the extent of LGE with a threshold of 6 standard deviations in 46 consecutive HCM patients with systolic dysfunction defined as LVEF <50 % (average 35 ± 12 %) who underwent cardiac magnetic resonance (35 males, mean age 59 ± 14 years). They were followed up over 1755 ± 594 days. The composite adverse cardiac events end point included cardiovascular death, lethal arrhythmia, cardioembolic stroke, and unplanned heart failure hospitalization. LGE was detected in all patients, and the mean extent was 30 ± 15 %. Twenty-nine patients developed adverse cardiac events. Multivariate Cox proportional hazard analysis revealed the extent of LGE as a good independent predictor of adverse cardiac events. Risk increased with the extent of LGE (hazard ratio = 1.62/10 % increase in LGE, 95 % confidence interval = 1.23-2.15, p < 0.001). LVEF was inversely related to the extent of LGE (r = -0.44; p = 0.002) and was also an independent predictor of adverse cardiac events. Risk decreased with LVEF (hazard ratio = 0.68/10 % increase in LVEF, 95 % confidence interval = 0.51-0.91, p = 0.010). The Akaike information criterion evaluating the fit of a model demonstrated that the extent of LGE was a better independent predictor of MACE than LVEF (Akaike information criterion = 172.20 and 178.09, respectively).The extent of LGE was a good independent predictor of adverse cardiac events and reflected mortality and morbidity more precisely than LVEF in HCM with systolic dysfunction. PMID:25820658

  19. Relationship between myocardial T2* values and cardiac volumetric and functional parameters in β-thalassemia patients evaluated by cardiac magnetic resonance in association with serum ferritin levels

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    Liguori, Carlo, E-mail: c.liguori@unicampus.it [Department of Diagnostic Imaging, Campus Bio Medico University, via Alvaro del Portillo 200, 00128 Rome (Italy); Pitocco, Francesca, E-mail: f.pitocco@unicampus.it [Department of Diagnostic Imaging, Campus Bio Medico University, via Alvaro del Portillo 200, 00128 Rome (Italy); Di Giampietro, Ilenia, E-mail: i.digiampietro@unicampus.it [Department of Diagnostic Imaging, Campus Bio Medico University, via Alvaro del Portillo 200, 00128 Rome (Italy); Vivo, Aldo Eros de, E-mail: devivoeros@gmail.com [Department of Diagnostic Imaging, Campus Bio Medico University, via Alvaro del Portillo 200, 00128 Rome (Italy); Schena, Emiliano, E-mail: e.schena@unicampus.it [Unit of Measurements and Biomedical Instrumentation, Campus Bio Medico University, via Alvaro del Portillo 200, 00128 Rome (Italy); Cianciulli, Paolo, E-mail: CIANCIULLI.PAOLO@aslrmc.it [Thalassemia Unit, Ospedale Sant Eugenio, Piazzale dell’Umanesimo 10, 00143 Rome (Italy); Zobel, Bruno Beomonte, E-mail: b.zobel@unicampus.it [Department of Diagnostic Imaging, Campus Bio Medico University, via Alvaro del Portillo 200, 00128 Rome (Italy)

    2013-09-15

    Purpose: Myocardial T2* cardiovascular magnetic resonance provides a rapid and reproducible assessment of cardiac iron load in thalassemia patients. Although cardiac involvement is mainly characterized by left ventricular dysfunction caused by iron overload, little is known about right ventricular function. The aim of this study was to assess the relationship between T2* value in myocardium and left–right ventricular volumetric and functional parameters and to evaluate the existing associations between left–right ventricles volumetric and functional parameter, myocardial T2* values and blood ferritin levels. Materials and methods: A retrospective analysis of 208 patients with β-thalassemia major and thalassemia intermedia was performed (109 males and 99 females; mean age 37.7 ± 13 years; 143 thalassemia major, 65 thalassemia intermedia). Myocardial iron load was assessed by T2* measurements, and volumetric functions were analyzed using the steady state free precession sequence. Results: A significant correlation was observed between EFLV and T2* (p = 0.0001), EFRV and T2* (p = 0.0279). An inverse correlation was present between DVLV and T2* (p = 0.0468), SVLV and T2* (p = 0.0003), SVRV and T2* (p = 0.0001). There was no significant correlation between cardiac T2* and LV–RV mass indices. A significant correlation was observed between T2* and serum ferritin levels (p < 0.001) and between EFLV and serum ferritin (p < 0.05). Conclusion: Myocardial iron load assessed by T2* cardiac magnetic resonance is associated with deterioration in left–right ventricular function; this is more evident when T2* values fall below 14 ms. CMR appears to be a promising approach for cardiac risk evaluation in TM patients.

  20. Relationship between myocardial T2* values and cardiac volumetric and functional parameters in β-thalassemia patients evaluated by cardiac magnetic resonance in association with serum ferritin levels

    International Nuclear Information System (INIS)

    Purpose: Myocardial T2* cardiovascular magnetic resonance provides a rapid and reproducible assessment of cardiac iron load in thalassemia patients. Although cardiac involvement is mainly characterized by left ventricular dysfunction caused by iron overload, little is known about right ventricular function. The aim of this study was to assess the relationship between T2* value in myocardium and left–right ventricular volumetric and functional parameters and to evaluate the existing associations between left–right ventricles volumetric and functional parameter, myocardial T2* values and blood ferritin levels. Materials and methods: A retrospective analysis of 208 patients with β-thalassemia major and thalassemia intermedia was performed (109 males and 99 females; mean age 37.7 ± 13 years; 143 thalassemia major, 65 thalassemia intermedia). Myocardial iron load was assessed by T2* measurements, and volumetric functions were analyzed using the steady state free precession sequence. Results: A significant correlation was observed between EFLV and T2* (p = 0.0001), EFRV and T2* (p = 0.0279). An inverse correlation was present between DVLV and T2* (p = 0.0468), SVLV and T2* (p = 0.0003), SVRV and T2* (p = 0.0001). There was no significant correlation between cardiac T2* and LV–RV mass indices. A significant correlation was observed between T2* and serum ferritin levels (p < 0.001) and between EFLV and serum ferritin (p < 0.05). Conclusion: Myocardial iron load assessed by T2* cardiac magnetic resonance is associated with deterioration in left–right ventricular function; this is more evident when T2* values fall below 14 ms. CMR appears to be a promising approach for cardiac risk evaluation in TM patients

  1. Severe Left Ventricular Hypertrophy, Small Pericardial Effusion, and Diffuse Late Gadolinium Enhancement by Cardiac Magnetic Resonance Suspecting Cardiac Amyloidosis: Endomyocardial Biopsy Reveals an Unexpected Diagnosis

    Directory of Open Access Journals (Sweden)

    Nina P. Hofmann

    2016-01-01

    Full Text Available Left ventricular (LV hypertrophy can be related to a multitude of cardiac disorders, such as hypertrophic cardiomyopathy (HCM, cardiac amyloidosis, and hypertensive heart disease. Although the presence of LV hypertrophy is generally associated with poorer cardiac outcomes, the early differentiation between these pathologies is crucial due to the presence of specific treatment options. The diagnostic process with LV hypertrophy requires the integration of clinical evaluation, electrocardiography (ECG, echocardiography, biochemical markers, and if required CMR and endomyocardial biopsy in order to reach the correct diagnosis. Here, we present a case of a patient with severe LV hypertrophy (septal wall thickness of 23 mm, LV mass of 264 g, and LV mass index of 147 g/m2, severely impaired longitudinal function, and preserved radial contractility (ejection fraction = 55%, accompanied by small pericardial effusion and diffuse late gadolinium enhancement (LGE by cardiac magnetic resonance (CMR. Due to the imaging findings, an infiltrative cardiomyopathy, such as cardiac amyloidosis, was suspected. However, amyloid accumulation was excluded by endomyocardial biopsy, which revealed the presence of diffuse myocardial fibrosis in an advanced hypertensive heart disease.

  2. Characteristics and clinical relevance of late gadolinium enhancement in cardiac magnetic resonance in patients with systemic sclerosis.

    Science.gov (United States)

    Sano, Makoto; Satoh, Hiroshi; Suwa, Kenichiro; Nobuhara, Mamoru; Saitoh, Takeji; Saotome, Masao; Urushida, Tsuyoshi; Katoh, Hideki; Shimoyama, Kumiko; Suzuki, Daisuke; Ogawa, Noriyoshi; Takehara, Yasuo; Sakahara, Harumi; Hayashi, Hideharu

    2015-11-01

    Cardiac involvement in systemic sclerosis (SSc) is considerably frequent in autopsy, but the early identification is clinically difficult. Recent advantages in cardiac magnetic resonance (CMR) enabled to detect myocardial fibrotic scar as late gadolinium enhancement (LGE). We aimed to examine the prevalence and distribution of LGE in patients with SSc, and associate them with clinical features, electrocardiographic abnormalities and cardiac function. Forty patients with SSc (58 ± 14 years-old, 35 females, limited/diffuse 25/15, disease duration 106 ± 113 months) underwent serological tests, 12-lead electrocardiogram (ECG) and CMR. Seven patients (17.5 %) showed LGE in 26 segments of left ventricle (LV). LGE distributed mainly in the basal to mid inter-ventricular septum and the right ventricular (RV) insertion points, but involved all the myocardial regions. More patients with LGE showed NYHA functional class II and more (71 vs. 21 %, p 125 pg/ml). When cardiac involvement of SSc was defined as low LVEF, ECG abnormalities or high NT-proBNP, the sensitivity, specificity positive and negative predictive values of LGE were 36, 92, 71 and 72 %, respectively. We could clarify the prevalence and distribution of LGE in Japanese patients with SSc. The presence of LGE was associated with cardiac symptom, conduction disturbance and impaired LV/RV contraction. PMID:24996373

  3. Stenosis of the branches of the neopulmonary artery after the arterial switch operation: A cardiac magnetic resonance imaging study

    International Nuclear Information System (INIS)

    The neonatal arterial switch operation (ASO) is now the standard of care for children born with transposition of the great arteries. Stenosis of the neopulmonary artery on long-term follow up is a known complication. We performed a retrospective analysis of eleven patients who underwent a cardiac magnetic resonance imaging (MRI) due to echocardiographic evidence suggestive of stenosis of the neopulmonary artery or its branches (mean estimated Doppler gradient 48 mmHg, min 30 mmHg, max 70 mmHg). A comprehensive evaluation of anatomy and perfusion was done by cardiac MRI. The branches of the neopulmonary artery (neo PA) showed decreased caliber in three patients unilaterally and in two patients, bilaterally. Magnetic resonance (MR) perfusion studies showed concomitant decreased flow, with discrepancy between the two lungs of 35/65% or worse, only in the three patients with unilateral obstruction, by two different MR perfusion methods. Cardiac MR can be used as a comprehensive non-invasive imaging technique to diagnose stenosis of the branches of the neopulmonary after the ASO, allowing evaluation of anatomy and function of the neoPA, its branches, and the differential perfusion to each lung, thus facilitating clinical decision making

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

    OpenAIRE

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

    2013-01-01

    Background 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. Methods 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) volu...

  5. Automated classification of LV regional wall motion based on spatio-temporal profiles from cardiac cine magnetic resonance imaging

    Science.gov (United States)

    Mantilla, Juan; Garreau, Mireille; Bellanger, Jean-Jacques; Paredes, José Luis

    2013-11-01

    Assessment of the cardiac Left Ventricle (LV) wall motion is generally based on visual inspection or quantitative analysis of 2D+t sequences acquired in short-axis cardiac cine-Magnetic Resonance Imaging (MRI). Most often, cardiac dynamic is globally analized from two particular phases of the cardiac cycle. In this paper, we propose an automated method to classify regional wall motion in LV function based on spatio-temporal pro les and Support Vector Machines (SVM). This approach allows to obtain a binary classi cation between normal and abnormal motion, without the need of pre-processing and by exploiting all the images of the cardiac cycle. In each short- axis MRI slice level (basal, median, and apical), the spatio-temporal pro les are extracted from the selection of a subset of diametrical lines crossing opposites LV segments. Initialized at end-diastole phase, the pro les are concatenated with their corresponding projections into the succesive temporal phases of the cardiac cycle. These pro les are associated to di erent types of information that derive from the image (gray levels), Fourier, Wavelet or Curvelet domains. The approach has been tested on a set of 14 abnormal and 6 healthy patients by using a leave-one-out cross validation and two kernel functions for SVM classi er. The best classi cation performance is yielded by using four-level db4 wavelet transform and SVM with a linear kernel. At each slice level the results provided a classi cation rate of 87.14% in apical level, 95.48% in median level and 93.65% in basal level.

  6. Left cardiac ventricle refinement of magnetic resonance images based on simulated annealing

    International Nuclear Information System (INIS)

    In this work we present a methodology for the refinement of segmentation of 2D magnet resonance images. The algorithm proposed here begins with an initial segmentation and, through the addition and exclusion of pixels in the contour of the actual segmentation, the desired segmentation s is obtained. At each step, two segmentation are available, the current and a candidate one. One of these two is selected according to deterministic (hybrid technique refinement) or stochastic (refinement by simulated annealing) minimization of an energy function.This function is composed of terms that account for the contrast int he contour, for the variance of the signal and for the shape of the segmented object. The methodology was evaluated over numeric phantoms and applied to real resonance magnetic images with success. This proposal can be easily extended to other kinds of image modalities. (author)

  7. Early recurrence of atrial fibrillation after catheter ablation with left atrial fibrosis identified at cardiac magnetic resonance by late gadolinium enhancement.

    Science.gov (United States)

    Totaro, Antonio; Casavecchia, Graziapia; Gravina, Matteo; Ieva, Riccardo; Santoro, Francesco; Grimaldi, Massimo; Pellegrino, Pier Luigi; Macarini, Luca; Di Biase, Matteo; Brunetti, Natale Daniele

    2016-08-01

    In patients with atrial fibrillation (AF), extensive atrial tissue fibrosis identified by delayed enhancement magnetic resonance imaging has been associated with early recurrence of AF after catheter ablation. We present a case of a patient with extensive atrial fibrosis and AF recurrence.The study of late gadolinium enhancement with cardiac magnetic resonance imaging in patients with AF could be a valuable noninvasive tool for the selection of patients suitable for successful catheter ablation. PMID:26826170

  8. Cardiovascular magnetic resonance in cardiac sarcoidosis with MR conditional pacemaker in situ

    OpenAIRE

    Hausenloy Derek; Harkness Allan; Plant Gordon T; Holdright Diana R; Quarta Giovanni; Hyare Harpreet; Moon James C

    2011-01-01

    Abstract Cardiovascular implantable electronic devices represent important limitations to magnetic resonance imaging (MRI). Recently, MRI-conditional dual chamber pacemakers and leads have become available. We describe a case of a patient with neuro-sarcoidosis presenting with diplopia and hydrocephalus requiring an MRI-conditional programmable ventriculo-peritoneal shunt, who developed complete heart block. In view of the ongoing need for neuro-imaging, MRI-conditional dual chamber pacemaker...

  9. Resonancia magnética cardíaca: aplicaciones clínicas Cardiac magnetic resonance: clinical applications

    Directory of Open Access Journals (Sweden)

    G. Bastarrika

    2005-04-01

    Full Text Available La enfermedad cardiovascular es la causa más frecuente de mortalidad en los países desarrollados y constituye un grave problema social, económico y sanitario. Aunque existen muy diversas técnicas útiles para diagnosticar las enfermedades cardíacas, con frecuencia es preciso realizar más de una prueba para llegar a un diagnóstico concreto. La resonancia magnética es una técnica inocua, bien tolerada y segura que actualmente se encuentra disponible en la mayoría de los centros hospitalarios. Esta técnica permite estudiar en una única exploración la anatomía del corazón y valorar de forma cualitativa, semicuantitativa y cuantitativa los parámetros de función cardíaca. Es útil para el estudio de las enfermedades valvulares, miocardiopatías y de la enfermedad pericárdica. Aporta información de la anatomía y función cardíaca y vascular en las cardiopatías congénitas complejas. Además, con la administración de contraste intravenoso, permite conocer la viabilidad miocárdica en la cardiopatía isquémica. Por tanto, la resonancia magnética cardíaca se perfila como una de las técnicas más prometedoras para el estudio de la patología cardíaca congénita y adquirida.Cardiovascular disease is the most frequent cause of mortality in the developed countries and represents a serious social, economic and health problem. Although very diverse, useful techniques exist for diagnosing cardiac diseases, it is frequently necessary to ask for more than one test to reach a specific diagnosis. Magnetic resonance is a harmless, well tolerated and safe technique, which is currently available in the majority of hospitals. This technique makes it possible in a single exploration to study the anatomy of the heart and to make a qualitative, semi-quantitative and quantitative assessment of the parameters of cardiac function. It provides information of cardiac and vascular anatomy and function in complex congenital cardiopathies. Besides

  10. Early detection of cardiac involvement in Miyoshi myopathy: 2D strain echocardiography and late gadolinium enhancement cardiovascular magnetic resonance

    Directory of Open Access Journals (Sweden)

    Kim Byoung

    2010-05-01

    Full Text Available Abstract Background Miyoshi myopathy (MM is an autosomal recessive distal myopathy characterized by early adult onset. Cardiomyopathy is a major clinical manifestation in other muscular dystrophies and an important prognostic factor. Although dysferlin is highly expressed in cardiac muscle, the effect of dysferlin deficiency in cardiac muscle has not been studied. We hypothesized that early myocardial dysfunction could be detected by 2D strain echocardiography and late gadolinium enhancement (LGE cardiovascular magnetic resonance (CMR. Method Five consecutive MM patients (3 male in whom we detected the DYSF gene mutation and age-matched healthy control subjects were included. None of the patients had history of cardiac disease or signs and symptoms of overt heart failure. Patients were studied using 2D strain echocardiography and CMR, with 2D strain being obtained using the Automated Function Imaging technique. Results All patients had preserved left ventricular systolic function. However, segmental Peak Systolic Longitudinal Strain (PSLS was decreased in 3 patients. Global PSLS was significantly lower in patients with MM than in control subjects (p = 0.005. Basal anterior septum, basal inferior septum, mid anterior, and mid inferior septum PSLS were significantly lower in patients with MM than in control subjects (P Conclusions Patients with MM showed subclinical involvement of the heart. 2D strain and LGE are sensitive methods for detecting myocardial dysfunction prior to the development of cardiovascular symptoms. The prognostic significance of these findings warrants further longitudinal follow-up.

  11. Identification of cardiac malformations in mice lacking Ptdsr using a novel high-throughput magnetic resonance imaging technique

    Directory of Open Access Journals (Sweden)

    Clarke Kieran

    2004-12-01

    Full Text Available Abstract Background Congenital heart defects are the leading non-infectious cause of death in children. Genetic studies in the mouse have been crucial to uncover new genes and signaling pathways associated with heart development and congenital heart disease. The identification of murine models of congenital cardiac malformations in high-throughput mutagenesis screens and in gene-targeted models is hindered by the opacity of the mouse embryo. Results We developed and optimized a novel method for high-throughput multi-embryo magnetic resonance imaging (MRI. Using this approach we identified cardiac malformations in phosphatidylserine receptor (Ptdsr deficient embryos. These included ventricular septal defects, double-outlet right ventricle, and hypoplasia of the pulmonary artery and thymus. These results indicate that Ptdsr plays a key role in cardiac development. Conclusions Our novel multi-embryo MRI technique enables high-throughput identification of murine models for human congenital cardiopulmonary malformations at high spatial resolution. The technique can be easily adapted for mouse mutagenesis screens and, thus provides an important new tool for identifying new mouse models for human congenital heart diseases.

  12. The examination of cardiac metabolism of patients with hypercholesterolemia by phosphorus-31 magnetic resonance spectroscopy

    CERN Document Server

    Martinek, M

    2001-01-01

    Objectives: we decided to investigate weather alterations in high energy phosphates occur in the myocardium of persons with hypercholesterolemia. Background: myocardial high energy phosphates have been shown to be reduced in various diseases of the heart such as coronary artery disease, heart failure and dilated cardiomyopathy. The latest studies on hypercholesterolemia show direct effects of high serum cholesterol on heart muscle cells, so do studies on statins. Methods: in the present study 32 male patients (mean age 48) with hypercholesterolemia and 27 male healthy volunteers (mean age 44,5) as age matched controls were included. The patients were divided into a statin-treated (n = 17) and an untreated subgroup (n = 15). Using a 1,5 Tesla whole-body magnetic resonance scanner (Siemens, Germany) phosphor-31 magnetic resonance spectroscopic imaging (31P MRSI) of the heart was performed in all subjects. The 31P MRSI slab (slab thickness = 40 mm, field of view = 320 mm, matrix 32 x 32, TR = 323 ms, TE 3 ms) co...

  13. Quantitative assessment of left ventricular function with dual-source CT in comparison to cardiac magnetic resonance imaging: initial findings

    International Nuclear Information System (INIS)

    Cardiac magnetic resonance imaging and echocardiography are currently regarded as standard modalities for the quantification of left ventricular volumes and ejection fraction. With the recent introduction of dual-source computedtomography (DSCT), the increased temporal resolution of 83 ms should also improve the assessment of cardiac function in CT. The aim of this study was to evaluate the accuracy of DSCT in the assessment of left ventricular functional parameters with cardiac magnetic resonance imaging (MRI) as standard of reference. Fifteen patients (two female, 13 male; mean age 50.8 ± 19.2 years) underwent CT and MRI examinations on a DSCT (Somatom Definition; Siemens Medical Solutions, Forchheim, Germany) and a 3.0-Tesla MR scanner (Magnetom Trio; Siemens Medical Solutions), respectively. Multiphase axial CT images were analysed with a semiautomatic region growing algorithms (Syngo Circulation; Siemens Medical Solutions) by two independent blinded observers. In MRI, dynamic cine loops of short axis slices were evaluated with semiautomatic contour detection software (ARGUS; Siemens Medical Solutions) independently by two readers. End-systolic volume (ESV), end-diastolic volume (EDV), ejection fraction (EF) and stroke volume (SV) were determined for both modalities, and correlation coefficient, systematic error, limits of agreement and inter-observer variability were assessed. In DSCT, EDV and ESV were 135.8 ± 41.9 ml and 54.9 ± 29.6 ml, respectively, compared with 132.1 ± 40.8 ml EDV and 57.6 ± 27.3 ml ESV in MRI. Thus, EDV was overestimated by 3.7 ml (limits of agreement -46.1/+53.6), while ESV was underestimated by 2.6 ml (-36.6/+31.4). Mean EF was 61.6 ± 12.4% in DSCT and 57.9 ± 9.0% in MRI, resulting in an overestimation of EF by 3.8% with limits of agreement at -14.7 and +22.2%. Rank correlation rho values were 0.81 for EDV (P = 0.0024), 0.79 for ESV (P 0.0031) and 0.64 for EF (P = 0.0168). The kappa value of inter-observer variability were

  14. Cardiac magnetic resonance imaging in patients with congenital heart disease; Kardiale MRT bei Patienten mit angeborenen Herzfehlern

    Energy Technology Data Exchange (ETDEWEB)

    Kreitner, Karl-Friedrich [Mainz Univ. Universitaetsmedizin Mainz (Germany). Klinik und Poliklinik fuer Diagnostische und Interventionelle Radiologie; Kaufmann, Lilly [Mainz Univ. (Germany); Sorantin, Erich [Univ.-Klinik fuer Radiologie, Graz (Austria). Klinische Abt. fuer Kinderradiologie

    2015-06-15

    The prevalence of congenital heart disease (CHD) is around 10 per 1000 live births in Germany. More than 90 % of these patients will survive into adulthood due to improvements in therapy. The classification of CHD may be based according to the anatomic structures involved, to the presence of an intracardiac shunt, the presence of a cyanosis and the intensity of therapy and complexity of the disease. Nearly half of all patients with CHD suffer from an intracardiac shunt, whereas complex cases such as patients with a tetralogy of Fallot or transposition of the great arteries are much more rare. Cardiac magnetic resonance imaging plays an important role in the work-up and follow-up of patients with CHD, especially after infancy and childhood. Depending on the abnormality in question, a multiparametric examination protocol is mandatory. Knowledge of operative procedures and findings of other imaging modalities help to optimize examination and time needed for it.

  15. Left atrial and ventricular function during dobutamine and glycopyrrolate stress in healthy young and elderly as evaluated by cardiac magnetic resonance

    DEFF Research Database (Denmark)

    Ahtarovski, Kiril A; Iversen, Kasper K; Lønborg, Jacob T;

    2012-01-01

    ) filling. We hypothesized that changes in LV compliance from normal aging are reflected in LA volume changes and that PS will augment these differences. We enrolled twenty young (20-30 yr) and twenty elderly (60-70 yr) healthy subjects and measured their LV and LA volumes by cardiac magnetic resonance...

  16. Novel phase-based noise reduction strategy for quantification of left ventricular function and mass assessment by cardiac CT: Comparison with cardiac magnetic resonance

    Energy Technology Data Exchange (ETDEWEB)

    Wai, Bryan, E-mail: bwai@partners.org [Cardiac MR PET CT Program, Division of Cardiology and Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts (United States); Thai, Wai-ee [Cardiac MR PET CT Program, Division of Cardiology and Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts (United States); Brown, Heather [Qi Imaging, Redwood City, California (United States); Truong, Quynh A. [Cardiac MR PET CT Program, Division of Cardiology and Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts (United States)

    2013-08-15

    Background: Tube current modulation in retrospective ECG gated cardiac computed tomography (CT) results in increased image noise and may reduce the accuracy of left ventricular (LV) ejection fraction (EF) and mass assessment. Objective: To examine the effects of a novel CT phase-based noise reduction (NR) algorithm on LV EF and mass quantification as compared to cardiac magnetic resonance (CMR). Methods: In 40 subjects, we compared the LV EF and mass between CT and CMR. In a subset of 24 subjects with tube current modulated CT, the effect of phase-based noise reduction strategies on contrast-to-noise ratio (CNR) and the assessment of LV EF and mass was compared to CMR. Results: There was excellent correlation between CT and CMR for EF (r = 0.94) and mass (r = 0.97). As compared to CMR, the limits of agreement improved with increasing strength of NR strategy. There was a systematic underestimation of LV mass by CT compared to CMR with no NR (−10.3 ± 10.1 g) and low NR (−10.3 ± 12.5 g), but was attenuated with high NR (−0.5 ± 8.3 g). Studies without NR had lower CNR compared to low and high NR at both the ES phase and ED phase (all p < 0.01). Conclusions: A high NR strategy on tube current modulated functional cardiac CT improves correlation of EF compared to CMR and reduces variability of EF and mass evaluation by increasing the CNR. In an effort to reduce radiation dose with tube current modulation, this strategy provides better image quality when LV function and mass quantification is needed.

  17. Novel phase-based noise reduction strategy for quantification of left ventricular function and mass assessment by cardiac CT: Comparison with cardiac magnetic resonance

    International Nuclear Information System (INIS)

    Background: Tube current modulation in retrospective ECG gated cardiac computed tomography (CT) results in increased image noise and may reduce the accuracy of left ventricular (LV) ejection fraction (EF) and mass assessment. Objective: To examine the effects of a novel CT phase-based noise reduction (NR) algorithm on LV EF and mass quantification as compared to cardiac magnetic resonance (CMR). Methods: In 40 subjects, we compared the LV EF and mass between CT and CMR. In a subset of 24 subjects with tube current modulated CT, the effect of phase-based noise reduction strategies on contrast-to-noise ratio (CNR) and the assessment of LV EF and mass was compared to CMR. Results: There was excellent correlation between CT and CMR for EF (r = 0.94) and mass (r = 0.97). As compared to CMR, the limits of agreement improved with increasing strength of NR strategy. There was a systematic underestimation of LV mass by CT compared to CMR with no NR (−10.3 ± 10.1 g) and low NR (−10.3 ± 12.5 g), but was attenuated with high NR (−0.5 ± 8.3 g). Studies without NR had lower CNR compared to low and high NR at both the ES phase and ED phase (all p < 0.01). Conclusions: A high NR strategy on tube current modulated functional cardiac CT improves correlation of EF compared to CMR and reduces variability of EF and mass evaluation by increasing the CNR. In an effort to reduce radiation dose with tube current modulation, this strategy provides better image quality when LV function and mass quantification is needed

  18. The examination of cardiac metabolism of patients with hypercholesterolemia by phosphorus-31 magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Objectives: we decided to investigate weather alterations in high energy phosphates occur in the myocardium of persons with hypercholesterolemia. Background: myocardial high energy phosphates have been shown to be reduced in various diseases of the heart such as coronary artery disease, heart failure and dilated cardiomyopathy. The latest studies on hypercholesterolemia show direct effects of high serum cholesterol on heart muscle cells, so do studies on statins. Methods: in the present study 32 male patients (mean age 48) with hypercholesterolemia and 27 male healthy volunteers (mean age 44,5) as age matched controls were included. The patients were divided into a statin-treated (n = 17) and an untreated subgroup (n = 15). Using a 1,5 Tesla whole-body magnetic resonance scanner (Siemens, Germany) phosphor-31 magnetic resonance spectroscopic imaging (31P MRSI) of the heart was performed in all subjects. The 31P MRSI slab (slab thickness = 40 mm, field of view = 320 mm, matrix 32 x 32, TR = 323 ms, TE 3 ms) contained the left anterior ventricular wall (region of interest = 32 ml). The measurement was triggered on electrocardiography. The ratios of phosphocreatinine (PCr) to β-adenosine-triphosphate (β-ATP) were calculated. Results: the myocardium of untreated patients with hypercholesterolemia shows significantly decreased ratios of PCr/β-ATP compared with patients treated with statins (2,09 vs. 2,45). When comparing the untreated group with healthy persons there was a trend to significance for a difference of the groups (2,09 vs. 2,34). Conclusion: with this study we demonstrate the first time alterations of high energy phosphates in the myocardium of persons with hypercholesterolemia and the beneficial effects of statins on these parameters. (author)

  19. Clinical study on the adriamycin induced cardiomyopathy using the cardiac magnetic resonance imaging. Total dose and cardiac dysfunction

    International Nuclear Information System (INIS)

    We studied cardiac functional disorders caused by Adoriamycin using gadolinium (Gd) contrast cine MRI. Forty-eight patients were given ACT (31 men and 17 women; mean age, 52±15 years). First, the relationship between dose and the left ventricular volume, cardiac function, left ventricular cardiac mass and localized wall motion were examined in all patients. Patients given a total dose of 300 mg/m2 or higher were assigned to the high dose group and those given doses under 300 mg/m2 to the low dose group. The same parameters were studied in both groups and compared. A 1.5-Tesla superconductive MRI was used for all studies. Cine images of the long and short axes at the papillary muscle level were obtained by ECG R-wave synchronized Gd contrast cine MRI. Left ventricular volume and cardiac function were analyzed using the long-axis cine images and the wall thickness in diastole and systole was measured at each site using the short-axis cine images. The percentage of wall thickness was calculated at each site. The mean ACT dose was 273.3±218.2 mg/m2. In all patients the total dose directly correlated with ESVI and inversely correlated with the ejection fraction (EF). In the high dose group, the total dose and EF were inversely correlated, but no significant differences were observed in the low dose group. In the high dose group, the ESVI was significantly greater and the SVI and EF were more significantly reduced than in the low dose group. In the high dose group, the thickness of the anterior, lateral and posterior walls, excluding the septum, was significantly lower than in the low dose group. However, changes in wall thickness were not significantly different between the groups. Gd contrast cine MRI was useful in examining cardiac functional disorders caused by anthracyclines. The total dose of anthracycline correlated directly with the ESVI, and inversely with the EF. A total dose of 300 mg/m2 appeared to be the borderline dose beyond which there were significant

  20. Clinical study on the adriamycin induced cardiomyopathy using the cardiac magnetic resonance imaging. Total dose and cardiac dysfunction

    Energy Technology Data Exchange (ETDEWEB)

    Yamaguchi, Kyoko; Teraoka, Kunihiko; Hirano, Masaharu [Tokyo Medical Coll. (Japan)

    2001-05-01

    We studied cardiac functional disorders caused by Adoriamycin using gadolinium (Gd) contrast cine MRI. Forty-eight patients were given ACT (31 men and 17 women; mean age, 52{+-}15 years). First, the relationship between dose and the left ventricular volume, cardiac function, left ventricular cardiac mass and localized wall motion were examined in all patients. Patients given a total dose of 300 mg/m{sup 2} or higher were assigned to the high dose group and those given doses under 300 mg/m{sup 2} to the low dose group. The same parameters were studied in both groups and compared. A 1.5-Tesla superconductive MRI was used for all studies. Cine images of the long and short axes at the papillary muscle level were obtained by ECG R-wave synchronized Gd contrast cine MRI. Left ventricular volume and cardiac function were analyzed using the long-axis cine images and the wall thickness in diastole and systole was measured at each site using the short-axis cine images. The percentage of wall thickness was calculated at each site. The mean ACT dose was 273.3{+-}218.2 mg/m{sup 2}. In all patients the total dose directly correlated with ESVI and inversely correlated with the ejection fraction (EF). In the high dose group, the total dose and EF were inversely correlated, but no significant differences were observed in the low dose group. In the high dose group, the ESVI was significantly greater and the SVI and EF were more significantly reduced than in the low dose group. In the high dose group, the thickness of the anterior, lateral and posterior walls, excluding the septum, was significantly lower than in the low dose group. However, changes in wall thickness were not significantly different between the groups. Gd contrast cine MRI was useful in examining cardiac functional disorders caused by anthracyclines. The total dose of anthracycline correlated directly with the ESVI, and inversely with the EF. A total dose of 300 mg/m{sup 2} appeared to be the borderline dose beyond

  1. Assessment of sub-clinical acute cellular rejection after heart transplantation: comparison of cardiac magnetic resonance imaging and endomyocardial biopsy

    International Nuclear Information System (INIS)

    Comparing the diagnostic value of multi-sequential cardiac magnetic resonance imaging (CMR) with endomyocardial biopsy (EMB) for sub-clinical cardiac allograft rejection. One hundred and forty-six examinations in 73 patients (mean age 53 ± 12 years, 58 men) were performed using a 1.5 Tesla system and compared to EMB. Examinations included a STIR (short tau inversion recovery) sequence for calculation of edema ratio (ER), a T1-weighted spin-echo sequence for assessment of global relative enhancement (gRE), and inversion-recovery sequences to visualize late gadolinium enhancement (LGE). Histological grade ≥1B was considered relevant rejection. One hundred and twenty-seven (127/146 = 87 %) EMBs demonstrated no or mild signs of rejection (grades ≤1A) and 19/146 (13 %) a relevant rejection (grade ≥1B). Sensitivity, specificity, positive predictive, and negative predictive values were as follows: ER: 63 %, 78 %, 30 %, and 93 %; gRE: 63 %, 70 %, 24 %, and 93 %; LGE: 68 %, 36 %, 13 %, and 87 %; with the combination of ER and gRE with at least one out of two positive: 84 %, 57 %, 23 %, and 96 %. ROC analysis revealed an area under the curve of 0.724 for ER and 0.659 for gRE. CMR parameters for myocarditis are useful to detect sub-clinical acute cellular rejection after heart transplantation. Comparable results to myocarditis can be achieved with a combination of parameters. (orig.)

  2. Assessment of sub-clinical acute cellular rejection after heart transplantation: comparison of cardiac magnetic resonance imaging and endomyocardial biopsy

    Energy Technology Data Exchange (ETDEWEB)

    Krieghoff, Christian; Hildebrand, Lysann; Grothoff, Matthias; Lehmkuhl, Lukas; Luecke, Christian; Andres, Claudia; Nitzsche, Stefan; Riese, Franziska; Gutberlet, Matthias [University Leipzig - Heart Centre, Department of Diagnostic and Interventional Radiology, Leipzig (Germany); Barten, Markus J.; Strueber, Martin; Mohr, Friedrich Wilhelm [University Leipzig - Heart Centre, Department of Cardiac Surgery, Leipzig (Germany)

    2014-10-15

    Comparing the diagnostic value of multi-sequential cardiac magnetic resonance imaging (CMR) with endomyocardial biopsy (EMB) for sub-clinical cardiac allograft rejection. One hundred and forty-six examinations in 73 patients (mean age 53 ± 12 years, 58 men) were performed using a 1.5 Tesla system and compared to EMB. Examinations included a STIR (short tau inversion recovery) sequence for calculation of edema ratio (ER), a T1-weighted spin-echo sequence for assessment of global relative enhancement (gRE), and inversion-recovery sequences to visualize late gadolinium enhancement (LGE). Histological grade ≥1B was considered relevant rejection. One hundred and twenty-seven (127/146 = 87 %) EMBs demonstrated no or mild signs of rejection (grades ≤1A) and 19/146 (13 %) a relevant rejection (grade ≥1B). Sensitivity, specificity, positive predictive, and negative predictive values were as follows: ER: 63 %, 78 %, 30 %, and 93 %; gRE: 63 %, 70 %, 24 %, and 93 %; LGE: 68 %, 36 %, 13 %, and 87 %; with the combination of ER and gRE with at least one out of two positive: 84 %, 57 %, 23 %, and 96 %. ROC analysis revealed an area under the curve of 0.724 for ER and 0.659 for gRE. CMR parameters for myocarditis are useful to detect sub-clinical acute cellular rejection after heart transplantation. Comparable results to myocarditis can be achieved with a combination of parameters. (orig.)

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

    International Nuclear Information System (INIS)

    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

  4. 自触发心脏磁共振成像%Self-gated cardiac magnetic resonance imaging

    Institute of Scientific and Technical Information of China (English)

    邓尚友; 方可; 王旭霞; 谭萍

    2012-01-01

    目的 探讨和实现一种自触发磁共振心脏成像(CMRI).方法 将心电图(ECG)信号和呼吸信号从监测信号中提取出来,然后将K空间数据重新排列、重建,得到心脏图像.结果 自触发CMRI克服了传统的导联法难以获得稳定ECG信号的缺点,可提高扫描效率,得到高品质的亮血和黑血小鼠心脏电影图像.结论 采用自触发CMRI可以实现小鼠心脏电影成像以及黑血成像,并用于评价其心脏结构和功能.%Objective To discuss and realize a type of self-gated cardiac magnetic resonance imaging (CMRI). Methods K space data were rearranged according to electrocardiogram (ECG) and respiration signals, and the cardiac images were reconstructed. Results ECG and respiration signals were extracted from the Navigator, which overcame the difficulty to get stable ECG signal using conventional lead. The method improved CMRI scanning efficiency. High quality bright-blood and black-blood mouse cardiac cine images were acquired. Conclusion Self-gated CMRI can realize cine CMRI and black-blood CMRI, which can be used to evaluate the structure and function of the heart in mice.

  5. The pulsatility volume index: an indicator of cerebrovascular compliance based on fast magnetic resonance imaging of cardiac and respiratory pulsatility.

    Science.gov (United States)

    Bianciardi, Marta; Toschi, Nicola; Polimeni, Jonathan R; Evans, Karleyton C; Bhat, Himanshu; Keil, Boris; Rosen, Bruce R; Boas, David A; Wald, Lawrence L

    2016-05-13

    The influence of cardiac activity on the viscoelastic properties of intracranial tissue is one of the mechanisms through which brain-heart interactions take place, and is implicated in cerebrovascular disease. Cerebrovascular disease risk is not fully explained by current risk factors, including arterial compliance. Cerebrovascular compliance is currently estimated indirectly through Doppler sonography and magnetic resonance imaging (MRI) measures of blood velocity changes. In order to meet the need for novel cerebrovascular disease risk factors, we aimed to design and validate an MRI indicator of cerebrovascular compliance based on direct endogenous measures of blood volume changes. We implemented a fast non-gated two-dimensional MRI pulse sequence based on echo-planar imaging (EPI) with ultra-short repetition time (approx. 30-50 ms), which stepped through slices every approximately 20 s. We constrained the solution of the Bloch equations for spins moving faster than a critical speed to produce an endogenous contrast primarily dependent on spin volume changes, and an approximately sixfold signal gain compared with Ernst angle acquisitions achieved by the use of a 90° flip angle. Using cardiac and respiratory peaks detected on physiological recordings, average cardiac and respiratory MRI pulse waveforms in several brain compartments were obtained at 7 Tesla, and used to derive a compliance indicator, the pulsatility volume index (pVI). The pVI, evaluated in larger cerebral arteries, displayed significant variation within and across vessels. Multi-echo EPI showed the presence of significant pulsatility effects in both S0 and [Formula: see text] signals, compatible with blood volume changes. Lastly, the pVI dynamically varied during breath-holding compared with normal breathing, as expected for a compliance indicator. In summary, we characterized and performed an initial validation of a novel MRI indicator of cerebrovascular compliance, which might prove useful

  6. Cardiac magnetic resonance imaging in dilated cardiomyopathy in adults - towards identification of myocardial inflammation

    Energy Technology Data Exchange (ETDEWEB)

    Voigt, Antje; Beling, Mark; Stangl, Karl [Charite-Universitaetsmedizin Berlin, Department of Cardiology, Campus Mitte, Berlin (Germany); Elgeti, Thomas; Durmus, Tahir; Idiz, Merve Ece; Schilling, Rene; Taupitz, Matthias; Wagner, Moritz [Charite-Universitaetsmedizin Berlin, Department of Radiology, Campus Mitte, Berlin (Germany); Butler, Craig [University of Alberta, Mazankowski Alberta Heart Institute, Edmonton (Canada); Klingel, Karin; Kandolf, Reinhard [University Hospital, Department of Molecular Pathology, Tuebingen (Germany); Kivelitz, Dietmar [Asklepios Klinik St. Georg, Department of Radiology, Hamburg (Germany)

    2011-05-15

    To assess active myocardial inflammation by cardiovascular magnetic resonance (CMR) and endomyocardial biopsy (EMB) amongst adult patients with dilated cardiomyopathy (DCM). We evaluated 23 adults with chronic DCM, who had successfully undergone both CMR and EMB within 3.5 {+-} 2.6 days. EMB was considered the gold standard. CMR assessment of myocardial inflammation used the following parameters as recommended by the recently published ''Lake Louise Criteria'': global myocardial oedema, global relative enhancement (RE), and late gadolinium enhancement (LGE). According to ''Lake Louise Criteria'', myocardial inflammation was diagnosed if two or more of the three above-mentioned parameters were positive. Myocardial inflammation was confirmed by immunohistology in 12 patients (52.2%). Sensitivity, specificity, and diagnostic accuracy of CMR to detect immunohistologically confirmed myocardial inflammation were 75.0%, 72.7%, and 73.9%, respectively. Sensitivity, specificity, and diagnostic accuracy of the individual CMR parameters to detect myocardial inflammation were as follows: global myocardial oedema, 91.7%, 81.8%, and 87.0%, respectively; global RE, 58.3%, 63.6%, and 60.9%, respectively; LGE, 58.3%, 45.4%, and 52.2%, respectively. Global myocardial oedema was identified as a promising CMR parameter for assessment of myocardial inflammation in patients with DCM. In these patients, global myocardial oedema yielded superior diagnostic performance compared to ''Lake Louise Criteria''. (orig.)

  7. Early assessment of sub-clinical cardiac involvement in systemic sclerosis (SSc) using delayed enhancement cardiac magnetic resonance (CE-MRI)

    Energy Technology Data Exchange (ETDEWEB)

    Di Cesare, Ernesto, E-mail: ernesto.dicesare@cc.univaq.it [Department of Radiology, University of L’Aquila, Via Vetoio 1, 67100 L’Aquila (Italy); Battisti, Sara; Di Sibio, Alessandra [Department of Radiology, University of L’Aquila, Via Vetoio 1, 67100 L’Aquila (Italy); Cipriani, Paola; Giacomelli, Roberto; Liakouli, Vasiliky; Ruscitti, Piero [Rheumatology Clinic, Department of Internal Medicine and Public Health, University of L’Aquila, L’Aquila (Italy); Masciocchi, Carlo [Department of Radiology, University of L’Aquila, Via Vetoio 1, 67100 L’Aquila (Italy)

    2013-06-15

    Objectives: Systemic sclerosis heart involvement (SHI) is one of systemic sclerosis (SSc) most frequent complications, both in diffuse (dcSSc) and limited (lcSSc) cutaneous forms of disease. Nowadays, SHI is a major factor decreasing SSc survival rate because, when clinically evident, is associated with 70% of mortality at 5 years. SHI shows different forms, primary and/or secondary. Primary myocardial SHI is characterized by fibrosis. Aim of our study is to assess the presence and pattern of fibrosis as detected by cardiac magnetic resonance (CMR) in systemic sclerosis. Methods: In this study, we used CE-MRI (contrast enhanced-MRI) in 58 female SSc patients. Images were evaluated to obtain functional parameters and to see presence, location and pattern (nodular, linear or diffuse) of myocardial LE, sign of fibrosis. CE-MRI findings were correlated with patients clinical setting. Results: Myocardial fibrosis was detected in 25 of 58 patients (43%). The main finding observed in 16 of these 25 patients was a late enhancement showing a linear pattern, without coronary distribution and sparing the sub-endocardial myocardial layers. A patchy nodular enhancement pattern was observed in 9 patients (36%). Patients with linear pattern presented dcSSc, on the contrary patients with nodular LE displayed the lcSSc form. Conclusions: This study shows that CE-MRI is a reliable technique to detect SHI earlier than other methods. SHI increase passive myocardial stiffness, proportional to collagen deposition degree, leading to cardiac remodelling with possible development of heart failure, even with normal ejection fraction. An early treatment of SHI might improve SSc patients outcome.

  8. Early assessment of sub-clinical cardiac involvement in systemic sclerosis (SSc) using delayed enhancement cardiac magnetic resonance (CE-MRI)

    International Nuclear Information System (INIS)

    Objectives: Systemic sclerosis heart involvement (SHI) is one of systemic sclerosis (SSc) most frequent complications, both in diffuse (dcSSc) and limited (lcSSc) cutaneous forms of disease. Nowadays, SHI is a major factor decreasing SSc survival rate because, when clinically evident, is associated with 70% of mortality at 5 years. SHI shows different forms, primary and/or secondary. Primary myocardial SHI is characterized by fibrosis. Aim of our study is to assess the presence and pattern of fibrosis as detected by cardiac magnetic resonance (CMR) in systemic sclerosis. Methods: In this study, we used CE-MRI (contrast enhanced-MRI) in 58 female SSc patients. Images were evaluated to obtain functional parameters and to see presence, location and pattern (nodular, linear or diffuse) of myocardial LE, sign of fibrosis. CE-MRI findings were correlated with patients clinical setting. Results: Myocardial fibrosis was detected in 25 of 58 patients (43%). The main finding observed in 16 of these 25 patients was a late enhancement showing a linear pattern, without coronary distribution and sparing the sub-endocardial myocardial layers. A patchy nodular enhancement pattern was observed in 9 patients (36%). Patients with linear pattern presented dcSSc, on the contrary patients with nodular LE displayed the lcSSc form. Conclusions: This study shows that CE-MRI is a reliable technique to detect SHI earlier than other methods. SHI increase passive myocardial stiffness, proportional to collagen deposition degree, leading to cardiac remodelling with possible development of heart failure, even with normal ejection fraction. An early treatment of SHI might improve SSc patients outcome

  9. Society for Cardiovascular Magnetic Resonance guidelines for reporting cardiovascular magnetic resonance examinations

    OpenAIRE

    van Rossum Albert C; Raman Subha V; McConnell Michael V; Lawson Mark A; Higgins Charles B; Friedrich Matthias G; Bogaert Jan G; Bluemke David; Hundley W Gregory; Flamm Scott; Kramer Christopher M; Nagel Eike; Neubauer Stefan

    2009-01-01

    Abstract These reporting guidelines are recommended by the Society for Cardiovascular Magnetic Resonance (SCMR) to provide a framework for healthcare delivery systems to disseminate cardiac and vascular imaging findings related to the performance of cardiovascular magnetic resonance (CMR) examinations.

  10. Cardiac magnetic resonance: is phonocardiogram gating reliable in velocity-encoded phase contrast imaging?

    International Nuclear Information System (INIS)

    To assess the diagnostic accuracy of phonocardiogram (PCG) gated velocity-encoded phase contrast magnetic resonance imaging (MRI). Flow quantification above the aortic valve was performed in 68 patients by acquiring a retrospectively PCG- and a retrospectively ECG-gated velocity-encoded GE-sequence at 1.5 T. Peak velocity (PV), average velocity (AV), forward volume (FV), reverse volume (RV), net forward volume (NFV), as well as the regurgitant fraction (RF) were assessed for both datasets, as well as for the PCG-gated datasets after compensation for the PCG trigger delay. PCG-gated image acquisition was feasible in 64 patients, ECG-gated in all patients. PCG-gated flow quantification overestimated PV (Δ 3.8 ± 14.1 cm/s; P = 0.037) and underestimated FV (Δ -4.9 ± 15.7 ml; P = 0.015) and NFV (Δ -4.5 ± 16.5 ml; P = 0.033) compared with ECG-gated imaging. After compensation for the PCG trigger delay, differences were only observed for PV (Δ 3.8 ± 14.1 cm/s; P = 0.037). Wide limits of agreement between PCG- and ECG-gated flow quantification were observed for all variables (PV: -23.9 to 31.4 cm/s; AV: -4.5 to 3.9 cm/s; FV: -35.6 to 25.9 ml; RV: -8.0 to 7.2 ml; NFV: -36.8 to 27.8 ml; RF: -10.4 to 10.2 %). The present study demonstrates that PCG gating in its current form is not reliable enough for flow quantification based on velocity-encoded phase contrast gradient echo (GE) sequences. (orig.)

  11. Assessing Late Cardiopulmonary Function in Patients with Repaired Tetralogy of Fallot Using Exercise Cardiopulmonary Function Test and Cardiac Magnetic Resonance

    Science.gov (United States)

    Yang, Ming-Chun; Chen, Chun-An; Chiu, Hsin-Hui; Chen, Ssu-Yuan; Wang, Jou-Kou; Lin, Ming-Tai; Chiu, Shuenn-Nan; Lu, Chun-Wei; Huang, Shu-Chien; Wu, Mei-Hwan

    2015-01-01

    Background Patients with repaired tetralogy of Fallot (TOF) usually experience progressive right ventricle (RV) dysfunction due to pulmonary regurgitation (PR). This could further worsen the cardiopulmonary function. This study aimed to compare the changes in patient exercise cardiopulmonary test and cardiac magnetic resonance imaging, and consider the implication of these changes. Methods Our study examined repaired TOF patients who underwent cardiopulmonary exercise test (CPET) to obtain maximal (peak oxygen consumption, peak VO2) and submaximal parameters (oxygen uptake efficiency plateau, oxygen uptake efficiency plateau (OUEP), and ratio of minute ventilation to carbon dioxide production, VE/VCO2 slope). Additionally, the hemodynamic status was assessed by using cardiac magnetic resonance. Criteria for exclusion included TOF patients with pulmonary atresia, atrioventricular septal defect, or absence of pulmonary valve syndrome. Results We enrolled 158 patients whose mean age at repair was 7.8 ± 9.1 years (range 0.1-49.2 years) and the mean patient age at CPET was 29.5 ± 12.2 years (range 7.0-57.0 years). Severe PR (PR fraction ≥ 40%) in 53 patients, moderate in 55, and mild (PR fraction 163 ml/m2. The mean left ventricular ejection fraction (LVEF) was 63 ± 8%, left ventricular end-diastolic volume index (LVEDVi) was 65 ± 12 ml/m2, and LVESVi was 25 ± 14 ml/m2. CPET revealed significantly decreased peak VO2 (68.5 ± 14.4% of predicted), and fair OUEP (90.3 ± 14.1% of predicted) and VE/VCO2 slope (27.1 ± 5.3). PR fraction and age at repair were negatively correlated with maximal and submaximal exercise indicators (peak VO2 and OUEP). Left ventricular (LV) function and size were positively correlated with peak VO2 and OUEP. Conclusions The results of CPET showed that patients with repaired TOF had a low maximal exercise capacity (peak VO2), but a fair submaximal exercise capacity (OUEP and VE/VCO2 slope), suggesting limited exercise capability in high

  12. Current artefacts in cardiac and chest magnetic resonance imaging: tips and tricks.

    Science.gov (United States)

    Alfudhili, Khalid; Masci, Pier G; Delacoste, Jean; Ledoux, Jean-B; Berchier, Grégoire; Dunet, Vincent; Qanadli, Salah D; Schwitter, Juerg; Beigelman-Aubry, Catherine

    2016-06-01

    Currently MRI is extensively used for the evaluation of cardiovascular and thoracic disorders because of the well-established advantages that include use of non-ionizing radiation, good contrast and high spatial resolution. Despite the advantages of this technique, numerous categories of artefacts are frequently encountered. They may be related to the scanner hardware or software functionalities, environmental factors or the human body itself. In particular, some artefacts may be exacerbated with high-field-strength MR machines (e.g. 3 T). Cardiac imaging poses specific challenges with respect to breath-holding and cardiac motion. In addition, new cardiac MR-conditional devices may also be responsible for peculiar artefacts. The image quality may thus be impaired and give rise to a misdiagnosis. Knowledge of acquisition and reconstruction techniques is required to understand and recognize the nature of these artefacts. This article will focus on the origin and appearance of the most common artefacts encountered in cardiac and chest MRI along with possible correcting methods to avoid or reduce them. PMID:26986460

  13. Safety of cardiac magnetic resonance and contrast angiography for neonates and small infants: a 10-year single-institution experience

    Energy Technology Data Exchange (ETDEWEB)

    Rangamani, Sheela; Li, Ling; Harvey, Lisa; Fletcher, Scott E.; Danford, David A.; Kutty, Shelby [University of Nebraska College of Medicine/Creighton University School of Medicine, Joint Division of Pediatric Cardiology, Omaha, NE (United States); Varghese, Joby [Children' s Hospital and Medical Center, Division of Pediatric Cardiac Anesthesia, Omaha, NE (United States); Hammel, James M.; Duncan, Kim F. [Children' s Hospital and Medical Center, Division of Cardiothoracic Surgery, Omaha, NE (United States)

    2012-11-15

    With increasing applications of cardiac magnetic resonance (CMR) and magnetic resonance angiography (MRA) for evaluation of congenital heart disease (CHD), safety of this technology in the very young is of particular interest. We report our 10-year experience with CMR in neonates and small infants with particular focus on the safety profile and incidence of adverse events (AEs). We reviewed clinical, anesthesia and nursing records of all children {<=}120 days of age who underwent CMR. We recorded variables including cardiac diagnosis, study duration, anesthesia type and agents, prostaglandin E1 (PGE1) dependence and gadolinium (Gd) use. Serially recorded temperature, systemic saturation (SpO{sub 2}) and cardiac rhythm were analyzed. Primary outcome measure was any AE during or <24 h after the procedure, including minor AEs such as hypothermia (axillary temperature {<=}95 F), desaturation (SpO{sub 2} drop {>=}10% below baseline) and bradycardia (heart rate {<=}100 bpm). Secondary outcome measure was unplanned overnight hospitalization of outpatients. Children (n = 143; 74 boys, 69 girls) had a median age of 6 days (1-117), and 98 were {<=}30 days at the time of CMR. The median weight was 3.4 kg (1.4-6 kg) and body surface area 0.22 m{sup 2} (0.13-0.32 m{sup 2}). There were 118 (83%) inpatients (108 receiving intensive care) and 25 (17%) outpatients. Indications for CMR were assessment of aortic arch (n = 57), complex CHD (n = 41), pulmonary veins (n = 15), vascular ring (n = 8), intracardiac mass (n = 8), pulmonary artery (n = 7), ventricular volume (n = 4), and systemic veins (n = 3). CMR was performed using a 1.5-T scanner and a commercially available coil. CMR utilized general anesthesia (GA) in 86 children, deep sedation (DS) in 50 and comforting methods in seven. MRA was performed in 136 children. Fifty-nine children were PGE1-dependent and 39 had single-ventricle circulation. Among children on PGE1, 43 (73%) had GA and 10 (17%) had DS. Twelve children (9%) had

  14. Safety of cardiac magnetic resonance and contrast angiography for neonates and small infants: a 10-year single-institution experience

    International Nuclear Information System (INIS)

    With increasing applications of cardiac magnetic resonance (CMR) and magnetic resonance angiography (MRA) for evaluation of congenital heart disease (CHD), safety of this technology in the very young is of particular interest. We report our 10-year experience with CMR in neonates and small infants with particular focus on the safety profile and incidence of adverse events (AEs). We reviewed clinical, anesthesia and nursing records of all children ≤120 days of age who underwent CMR. We recorded variables including cardiac diagnosis, study duration, anesthesia type and agents, prostaglandin E1 (PGE1) dependence and gadolinium (Gd) use. Serially recorded temperature, systemic saturation (SpO2) and cardiac rhythm were analyzed. Primary outcome measure was any AE during or 2 drop ≥10% below baseline) and bradycardia (heart rate ≤100 bpm). Secondary outcome measure was unplanned overnight hospitalization of outpatients. Children (n = 143; 74 boys, 69 girls) had a median age of 6 days (1-117), and 98 were ≤30 days at the time of CMR. The median weight was 3.4 kg (1.4-6 kg) and body surface area 0.22 m2 (0.13-0.32 m2). There were 118 (83%) inpatients (108 receiving intensive care) and 25 (17%) outpatients. Indications for CMR were assessment of aortic arch (n = 57), complex CHD (n = 41), pulmonary veins (n = 15), vascular ring (n = 8), intracardiac mass (n = 8), pulmonary artery (n = 7), ventricular volume (n = 4), and systemic veins (n = 3). CMR was performed using a 1.5-T scanner and a commercially available coil. CMR utilized general anesthesia (GA) in 86 children, deep sedation (DS) in 50 and comforting methods in seven. MRA was performed in 136 children. Fifty-nine children were PGE1-dependent and 39 had single-ventricle circulation. Among children on PGE1, 43 (73%) had GA and 10 (17%) had DS. Twelve children (9%) had adverse events (AEs) - one major and 11 minor. Of those 12, nine children had GA (10%) and three had DS (6%). The single major AE was

  15. The effect of obesity on electrocardiographic detection of hypertensive left ventricular hypertrophy: recalibration against cardiac magnetic resonance.

    Science.gov (United States)

    Rodrigues, J C L; McIntyre, B; Dastidar, A G; Lyen, S M; Ratcliffe, L E; Burchell, A E; Hart, E C; Bucciarelli-Ducci, C; Hamilton, M C K; Paton, J F R; Nightingale, A K; Manghat, N E

    2016-03-01

    Electrocardiograph (ECG) criteria for left ventricular hypertrophy (LVH) are a widely used clinical tool. We recalibrated six ECG criteria for LVH against gold-standard cardiac magnetic resonance (CMR) and assessed the impact of obesity. One hundred and fifty consecutive tertiary hypertension clinic referrals for CMR (1.5 T) were reviewed. Patients with cardiac pathology potentially confounding hypertensive LVH were excluded (n=22). The final sample size was 128 (age: 51.0±15.2 years, 48% male). LVH was defined by CMR. From a 12-lead ECG, Sokolow-Lyon voltage and product, Cornell voltage and product, Gubner-Ungerleidger voltage and Romhilt-Estes score were evaluated, blinded to the CMR. ECG diagnostic performance was calculated. LVH by CMR was present in 37% and obesity in 51%. Obesity significantly reduced ECG sensitivity, because of significant attenuation in mean ECG values for Cornell voltage (22.2±5.7 vs 26.4±9.4 mm, PECG specificity, because of significantly higher prevalence of LV remodeling (no LVH but increased mass-to-volume ratio) in obese subjects without LVH (36% vs 16%, PECG LVH criteria values. Obesity-specific partition values were generated at fixed 95% specificity; Cornell voltage had highest sensitivity in non-obese (56%) and Sokolow-Lyon product in obese patients (24%). Obesity significantly lowers ECG sensitivity at detecting LVH, by attenuating ECG LVH values, and lowers ECG specificity through changes associated with LV remodeling. Our obesity-specific ECG partition values could improve the diagnostic performance in obese patients with hypertension. PMID:26040440

  16. Inter- and intra-rater reproducibility of semiautomatic determination of volume parameters in cardiac magnetic resonance imaging

    International Nuclear Information System (INIS)

    Purpose: The purpose of this study was to evaluate inter- and intra-rater reproducibility in volume assessment using cardiac magnetic resonance imaging (CMRI). Methods: Twenty-five healthy volunteers and 106 patients were included into this retrospective study and received CMRI. The patients were divided in three groups (group I, 80 patients with arrhythmia; group II, 20 patients with cardiomyopathy; group III, 6 patients after correction of septum defects). Therefore, the images were semiautomatically segmented by an experienced and an unexperienced radiologists. The analysis of end-diastolic volume (EDV), end-systolic volume (ESV) and stroke volume (SV) as well as ejection fraction (EF) and myocardial mass (MM) were performed twice by an experienced and an unexperienced radiologists. The intra-class correlation coefficients (ICC) were determined for the evaluation of inter- and intra-rater variance. Results: The intra-rater reproducibility for determination of EF, ESV, EDV and MM was excellent with ICCs ranging from 0.88 to 0.99 (all p < 0.001). The inter-observer reproducibility for these parameters was also excellent with ICCs ranging from 0.91 to 0.98 (all p < 0.001). The assessment of the SV showed an excellent intra-rater agreement with ICCs of 0.96 and 0.92 (both p < 0.001), but only a moderate ICC for the inter-rater reproducibility (0.54, p < 0.001). Conclusions: Our study shows that assessment of cardiac volumes can be performed on CMRIs with an excellent reproducibility by both experienced and unexperienced investigators

  17. Development of an automated processing method to detect still timing of cardiac motion for coronary magnetic resonance angiography

    Science.gov (United States)

    Asou, Hiroya; Ichikawa, Katsuhiro; Imada, Naoyuki; Masuda, Takanori; Satou, Tomoyasu

    2011-03-01

    Whole-heart coronary magnetic resonance angiography (WH-MRA) is useful noninvasive examination. Its signal acquisition is performed during very short still timing in each cardiac motion cycle, and therefore the adequate still timing selection is important to obtain the better image quality. However, since the current available selection method is only manual one using visual comparison of cine MRI images with different phases, the selected timings are often incorrect and their reproducibility is not sufficient. We developed an automated selection method to detect the best still timing for the WH-MRA and compared the automated method with conventional manual one. Cine MRI images were used for the analysis. In order to extract the high-speed cardiac cine image, each phase directional pixel set at each pixel position in all cine images were processed by a high-pass filtering using the Fourie transform. After this process, the cine images with low speed timing became dark, and the optimal timing could be determined by a threshold processing. We took ten volunteers' WH-MRA with the manually and automatically selected timings, and visually assessed image quality of each image on a 5-point scale (1=excellent, 2=very good, 3=good, 4=fair, 5=poor). The mean scores of the manual and automatic methods for right coronary arteries (RCA), LDA left anterior descending arteries (LAD) and LCX left circumflex arteries (LCX) were 4.2+/-0.38, 4.1+/-0.44, 3.9+/-0.52 and 4.1+/-0.42, 4.1+/-0.24, 3.2+/-0.35 respectively. The score were increased by our method in the RCA and LCX, and the LCX was significant (pcardiac phase more accurately than or equally to the conventional manual method.

  18. Myocardial inflammation after binge drinking assessed by cardiac magnetic resonance imaging

    OpenAIRE

    Aiche, Sascha

    2011-01-01

    Background: Chronic alcohol abuse leads to inflammatory changes in myocardium. The aim of this study was to determine acute effects of excessive consumption of alcohol – binge drinking – and hangover on the heart especially in myocardium. We assumed that binge drinking leads to detectable changes in myocardium. Methods: Cardiac-MRI (CMR) was the diagnostic method. Evaluated parameters were T2-Ratio, relative enhancement, late enhancement and left ventricular function. Additionally humoral...

  19. Acute oedema in the evaluation of microvascular reperfusion and myocardial salvage in reperfused myocardial infarction with cardiac magnetic resonance imaging

    International Nuclear Information System (INIS)

    The accurate measurement of myocardial salvage is critical to the ongoing refinement of reperfusion strategies in acute myocardial infarction (AMI). Cardiac magnetic resonance imaging (CMR) can define the area at risk in AMI by the presence of myocardial oedema, identified by high signal intensity on T2-weighted imaging with a short inversion time inversion-recovery (STIR) sequence. In addition, myocardial necrosis can be identified with CMR delayed contrast enhanced imaging. In this prospective study we examined the relationship of acute oedema and necrosis with impaired microvascular reperfusion. We also evaluated acute oedema as a marker of the area at risk in AMI, for the purposes of documenting myocardial salvage. CMR was performed on 15 patients with (AMI), within 24 h of successful percutaneous coronary intervention (PCI). Left ventricular (LV) systolic dysfunction was defined by a systolic thickening 0.5). The extent of myocardial salvage correlated with recovery of systolic function (R = 0.241, P < 0.05), which was strongest in LV segments with severely reduced systolic function (R = 0.422, P < 0.01). Conclusions: In acutely reperfused AMI, oedema can be used to identify the area at risk for the purpose of calculating myocardial salvage. The correlation between myocardial oedema and reperfusion status suggests a pathological role of acute oedema in the impairment of microvascular reperfusion.

  20. Correlation between myocardial fibrosis and the occurrence of atrial fibrillation in hypertrophic cardiomyopathy: A cardiac magnetic resonance imaging study

    Energy Technology Data Exchange (ETDEWEB)

    Pujadas, S., E-mail: sandrapujadas@gmail.co [Cardiac Imaging Unit, Cardiology Department, Hospital de la Santa Creu i Sant Pau, Av. Pare M Claret 167, 08025 Barcelona (Spain); Vidal-Perez, R. [Cardiac Imaging Unit, Cardiology Department, Hospital de la Santa Creu i Sant Pau, Av. Pare M Claret 167, 08025 Barcelona (Spain); Hidalgo, A. [Radiology Department, Hospital de la Santa Creu i Sant Pau, Av. Pare M Claret 167, 08025 Barcelona (Spain); Leta, R.; Carreras, F.; Barros, A. [Cardiac Imaging Unit, Cardiology Department, Hospital de la Santa Creu i Sant Pau, Av. Pare M Claret 167, 08025 Barcelona (Spain); Bayes-Genis, A. [Cardiomyopathy and Cardiac Transplant Unit, Cardiology Department, Hospital de la Santa Creu i Sant Pau, Av. Pare M Claret 167, 08025 Barcelona (Spain); Subirana, M.T. [Congenital Heart Disease Unit, Hospital de la Santa Creu i Sant Pau, Av. Pare M Claret 167, 08025 Barcelona (Spain); Pons-Llado, Guillem [Cardiac Imaging Unit, Cardiology Department, Hospital de la Santa Creu i Sant Pau, Av. Pare M Claret 167, 08025 Barcelona (Spain)

    2010-08-15

    Cardiac magnetic resonance imaging (CMR) in hypertrophic cardiomyopathy (HCM) often shows delayed contrast enhancement (DE) representing regions of focal myocardial fibrosis. Atrial fibrillation (AF) is a commonly reported complication of HCM. We determined the relationship between the presence of left ventricular myocardial fibrosis (LVMF) detected by DE-CMR and the occurrence AF in a series of patients with HCM. 67 patients with HCM (47 males; mean age 50.1 {+-} 18.5 years) were studied by CMR measuring mass of LVMF, left ventricular mass, volume and function, and left atrial (LA) area. AF was present in 17 (25%) patients. LVMF was observed in 57% of patients. AF was significantly more frequent in patients who also showed LVMF, compared with the group without LVMF (42.1% vs. 3.4%, respectively; p < 0.0001). LA size was larger in patients showing DE (LA area: 37.4 {+-} 11.1 vs. 25.9 {+-} 6.8 cm{sup 2}; respectively, p = 0.0001). AF in HCM is related with myocardial fibrosis detected by DE-CMR and dilatation of the LA. This fact adds to the proven adverse prognostic value of myocardial fibrosis in HCM, thus, reinforcing the usefulness of this technique in the assessment of these patients.

  1. Prognostic value of cardiac magnetic resonance imaging for idiopathic pulmonary arterial hypertension before initiating intravenous prostacyclin therapy

    International Nuclear Information System (INIS)

    Because few have reported the prognostic significance of cardiac magnetic resonance imaging (CMR) for idiopathic pulmonary arterial hypertension (IPAH), in this study we evaluated the value of CMR measurements as a prognostic predictor of IPAH before starting intravenous prostacyclin therapy. A total of 121 consecutive CMR studies for evaluating right ventricular (RV) function were reviewed. Forty-one patients were diagnosed with IPAH and served as the study group. Factors, such as age, sex, New York Heart Association functional class (NYHAFC), 6-min walk test, plasma brain natriuretic peptide level, serum uric acid level and CMR measurements were analyzed as predictors of first hospitalization and death. The mean follow-up period was 1,350±769 days. Nine patients were hospitalized because of heart failure, and 4 patients died from cardiopulmonary causes. The univariate analyses suggested that the left ventricular (LV) mass index, the left and right ventricular end-diastolic volume indices (LVEDVI, RVEDVI), the LV and RV end-systolic volume indices (LVESVI, RVESVI) and NYHAFC predicted the risk for hospitalization and that RVEDVI, RVESVI and NYHAFC predicted mortality. The multivariate analyses suggested that RVEDVI and NYHAFC are independent predictors of both hospitalization and mortality. The effects of RVEDVI and NYHAFC on hospitalization were not substantially affected by the concomitant medication. In IPAH patients, the RVEDVI predicts both hospitalization for right heart failure and mortality before initiating intravenous prostacyclin therapy. (author)

  2. Cardiac magnetic resonance imaging in patients with chest pain, high troponin levels and absence of coronary artery obstruction

    International Nuclear Information System (INIS)

    The prevalence of myocardial infarction with angiographically normal coronary arteries is approximately 7-10%. The etiological diagnosis is sometimes difficult and is important in terms of clinical practice and prognosis. The goal of our study was to show a series of consecutive patients with an initial diagnosis of acute coronary syndrome with high troponin levels and absence of coronary artery obstruction in which cardiac magnetic resonance imaging (CMRI) gave a description of the myocardial lesion, orientating towards the etiological diagnosis. From January 2005 to December 2009, 720 consecutive patients with an initial diagnosis of acute coronary syndrome and elevated troponins were included; 64 of these patients did not present angiographically significant coronary artery stenosis. Within 72 ± 24 h after coronary angiography, these patients underwent CMRI using b-SSFP sequences for cine imaging in short-axis, 2-, 3- and 4- chamber views for the evaluation of segmental wall motion, with T2-weighted and delayed enhancement (DE) images of the myocardium with an 'inversion-recovery' sequence. The following diagnoses were made: myocarditis (39 patients); myocardial infarction (12 patients); Tako-Tsubo syndrome (8 patients); apical hypertrophic cardiomyopathy (2 patients); 3 patients remained without diagnosis. These findings demonstrate the usefulness of CMRI in the clinical scenario of patients with chest pain, inconclusive ECG findings and high troponin levels with angiographically normal coronary arteries. The presence and distribution pattern of DE make it possible to define the etiological diagnosis and interpret the physiopathological process. (authors)

  3. Correlation between myocardial fibrosis and the occurrence of atrial fibrillation in hypertrophic cardiomyopathy: A cardiac magnetic resonance imaging study

    International Nuclear Information System (INIS)

    Cardiac magnetic resonance imaging (CMR) in hypertrophic cardiomyopathy (HCM) often shows delayed contrast enhancement (DE) representing regions of focal myocardial fibrosis. Atrial fibrillation (AF) is a commonly reported complication of HCM. We determined the relationship between the presence of left ventricular myocardial fibrosis (LVMF) detected by DE-CMR and the occurrence AF in a series of patients with HCM. 67 patients with HCM (47 males; mean age 50.1 ± 18.5 years) were studied by CMR measuring mass of LVMF, left ventricular mass, volume and function, and left atrial (LA) area. AF was present in 17 (25%) patients. LVMF was observed in 57% of patients. AF was significantly more frequent in patients who also showed LVMF, compared with the group without LVMF (42.1% vs. 3.4%, respectively; p 2; respectively, p = 0.0001). AF in HCM is related with myocardial fibrosis detected by DE-CMR and dilatation of the LA. This fact adds to the proven adverse prognostic value of myocardial fibrosis in HCM, thus, reinforcing the usefulness of this technique in the assessment of these patients.

  4. 7 Tesla (T) human cardiovascular magnetic resonance imaging using FLASH and SSFP to assess cardiac function: validation against 1.5 T and 3 T

    OpenAIRE

    Suttie, J. J.; DelaBarre, L; Pitcher, A.; van de Moortele, P. F.; Dass, S; Snyder, C. J.; Francis, J M; Metzger, G. J.; Weale, P.; Ugurbil, K; Neubauer, S.; Robson, M; Vaughan, T

    2011-01-01

    We report the first comparison of cardiovascular magnetic resonance imaging (CMR) at 1.5 T, 3 T and 7 T field strengths using steady state free precession (SSFP) and fast low angle shot (FLASH) cine sequences. Cardiac volumes and mass measurements were assessed for feasibility, reproducibility and validity at each given field strength using FLASH and SSFP sequences. Ten healthy volunteers underwent retrospectively electrocardiogram (ECG) gated CMR at 1.5 T, 3 T and 7 T using FLASH and SSFP se...

  5. 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 ... 8 MB) Also available in Other Language versions . Magnetic Resonance Imaging (MRI) is a medical imaging procedure for making ...

  6. Role of magnetic resonance imaging for evaluation of tumors in the cardiac region

    Energy Technology Data Exchange (ETDEWEB)

    Kaminaga, T.; Takeshita, T.; Kimura, I. [Dept. of Radiology/Pathology, Teikyo Univ. Medical School, Tokyo (Japan)

    2003-12-01

    The aim of this study was to review the role of MRI in the assessment of heart neoplasm, 25 cases with heart neoplasm (10 myxoma, 6 rhabdomyoma, 5 angiosarcoma, 2 mesothelioma, 1 lymphoma, and 1 fibroma) were examined with MRI and echocardiography. Multislice T1- and T2-weighted spin-echo images and static gradient-echo images were taken in appropriate directions with electrocardiogram gating. Gadolinium enhancement was performed in 21 cases. Transthoracic echocardiography was performed in all cases. Except for the 5 patients with rhabdomyoma, the pathological diagnosis was obtained. MRI proved to be useful for tissue characterization of myxoma, angiosarcoma, mesothelioma, and fibroma in cases with tuberous sclerosis. MRI also proved to be useful for detection of the tumor, depiction of contour, relation with other cardiac structures, in cases with myxoma, angiosarcoma, mesothelioma, lymphoma, and fibroma. In the differential diagnosis, MRI provided important information in cases with myxoma, rhabdomyoma, angiosarcoma, and fibroma. In cases with tumors expanding into the mediastinum, such as mesothelioma and fibroma in this report, MRI was useful in determining the location and border. In cases with tumors adjacent to pericardium, MRI was useful in detecting pericardial invasion. Gadolinium enhancement added useful information in cases with myxoma, rhabdomyoma, angiosarcoma, and mesothelioma. The role of MRI with and without Gd enhancement differs somewhat in individual types of heart neoplasm, and adaptation must be considered in each kind of neoplasm. On the other hand, MRI is an essential examination in all cases with a cardiac mass, which has not been diagnosed, since it may provide useful information for the differential diagnosis. (orig.)

  7. Validation of an evaluation routine for left ventricular volumes, ejection fraction and wall motion from gated cardiac FDG PET: a comparison with cardiac magnetic resonance imaging

    International Nuclear Information System (INIS)

    The aim of this study was to validate the estimation of left ventricular end-diastolic and end-systolic volumes (EDV, ESV) and ejection fraction (LVEF) as well as wall motion analysis from gated fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) in patients with severe coronary artery disease (CAD) using software originally designed for gated single-photon emission tomography (SPET). Thirty patients with severe CAD referred for myocardial viability diagnostics were investigated using a standard FDG PET protocol enhanced with gated acquisition (8 gates per cardiac cycle). EDV, ESV and LVEF were calculated using standard software designed for gated SPET (QGS). Wall motion was analysed using a visual four-point wall motion score on a 17-segment model. As a reference, all patients were also examined within a median of 3 days with cardiovascular cine magnetic resonance imaging (cMRI) (20 gates per cardiac cycle). Furthermore, all gated FDG PET data sets were reoriented in a second run with deliberately misaligned axes to test the quantification procedure for robustness. Correlation between the results of gated FDG PET and cMRI was very high for EDV and ESV (R=0.96 and R=0.97) and for LVEF (R=0.95). With gated FDG PET, there was a non-significant tendency to underestimate EDV (174±61 ml vs 179±59 ml, P=0.21) and to overestimate ESV (124±58 ml vs 122±60 ml, P=0.65), resulting in underestimated LVEF values (31.5%±9.4% vs 34.2%±12.4%, P<0.003). The results of reorientations 1 and 2 showed very high correlations (for all R≥0.99). Segmental wall motion analysis revealed good agreement between gated FDG PET data and cMRI (kappa =0.62±0.03). In conclusion, despite small systematic differences which contributed mainly to the lower temporal resolution of gated FDG PET, agreement between gated FDG PET and cMRI was good across a wide range of volumes and LVEF values as well as for wall motion analysis. Therefore, gated FDG PET provides clinically

  8. Magnetic resonance angiography

    Science.gov (United States)

    MRA; Angiography - magnetic resonance ... Kwong RY. Cardiovascular Magnetic Resonance Imaging. In: Bonow RO, Mann DL, Zipes DP, Libby P, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine . ...

  9. Cardiac function in growth hormone deficient patients before and after 1 year with replacement therapy: a magnetic resonance imaging study

    DEFF Research Database (Denmark)

    Andreassen, Mikkel; Faber, Jens Oscar; Petersen, Claus Leth;

    2011-01-01

    gold standard method cardiac magnetic resonance imaging (CMRI) and measurements of circulating levels of B-type natriuretic peptides. Sixteen patients (8 males and 8 females, mean age 49 years (range 18-75)) with severe GHD and 16 matched control subjects were included. CMRI was performed at baseline......Assessed by conventional echocardiography the influence of growth hormone deficiency (GHD) and effects of replacement therapy on left ventricle (LV) function and mass (LVM) have shown inconsistent results. We aimed to evaluate cardiac function before and during replacement therapy employing the...... (range 63-80%), cardiac output index and levels of BNP and NT-proBNP were similar at baseline in patients compared to controls (P-values from 0.09 to 0.37). The patients had significantly smaller LV end-diastolic volume index (P = 0.032) and end-systolic volume index (P = 0.038). No significant change in...

  10. 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.)

  11. Preliminary assessment of cardiac short term safety and efficacy of manganese chloride for cardiovascular magnetic resonance in humans

    Directory of Open Access Journals (Sweden)

    Kalaf Jose M

    2011-01-01

    Full Text Available Abstract Background Manganese based agents are intracellular and accumulate inside myocytes allowing for different imaging strategies compared to gadolinium contrasts. While previous agents release manganese very slowly in the circulation, MnCl2 allows for rapid Mn2+ uptake in myocytes, creating a memory effect that can be potentially explored. Data on animal models are very encouraging but the safety and efficacy of this approach in humans has not yet been investigated. Therefore, our objectives were to study the safety and efficacy of a rapid infusion of manganese chloride (MnCl2 for cardiovascular magnetic resonance (CMR in humans. Methods Fifteen healthy volunteers underwent a CMR scan on a 1.5 T scanner. Before the infusion, cardiac function was calculated and images of a short axis mid-ventricular slice were obtained using a 2D and 3D gradient-echo inversion recovery (GRE-IR sequence, a phase-sensitive IR sequence and a single breath-hold segmented IR prepared steady-state precession acquisition for T1 calculations. MnCl2 was infused over three minutes at a total dose of 5 μMol/kg. Immediately after the infusion, and at 15 and 30 minutes later, new images were obtained and cardiac function re-evaluated. Results There was a significant decrease in T1 values compared to baseline, sustained up to 30 minutes after the MnCl2 infusion (pre,839 ± 281 ms; 0 min, 684 ± 99; 15 min, 714 ± 168; 30 min, 706 ± 172, P = 0.003. The 2D and 3D GRE-IR sequence showed the greatest increase in signal-to-noise ratio compared to the other sequences (baseline 6.6 ± 4.2 and 9.7 ± 5.3; 0 min, 11.3 ± 4.1 and 15.0 ± 8.7; 15 min, 10.8 ± 4.0 and 16.9 ± 10.2; 30 min, 10.6 ± 5.2 and 16.5 ± 8.3, P 2 with no major adverse events, despite all reporting transient facial flush. Conclusions In the short term, MnCl2 appears safe for human use. It effectively decreases myocardium T1, maintaining this effect for a relatively long period of time and allowing for the

  12. Angiographic correlations of patients with small vessel disease diagnosed by adenosine-stress cardiac magnetic resonance imaging

    Directory of Open Access Journals (Sweden)

    Scheck Roland

    2008-01-01

    Full Text Available Abstract Cardiac magnetic resonance imaging (CMR with adenosine-stress myocardial perfusion is gaining importance for the detection and quantification of coronary artery disease (CAD. However, there is little knowledge about patients with CMR-detected ischemia, but having no relevant stenosis as seen on coronary angiography (CA. The aims of our study were to characterize these patients by CMR and CA and evaluate correlations and potential reasons for the ischemic findings. 73 patients with an indication for CA were first scanned on a 1.5T whole-body CMR-scanner including adenosine-stress first-pass perfusion. The images were analyzed by two independent investigators for myocardial perfusion which was classified as subendocardial ischemia (n = 22, no perfusion deficit (n = 27, control 1, or more than subendocardial ischemia (n = 24, control 2. All patients underwent CA, and a highly significant correlation between the classification of CMR perfusion deficit and the degree of coronary luminal narrowing was found. For quantification of coronary blood flow, corrected Thrombolysis in Myocardial Infarction (TIMI frame count (TFC was evaluated for the left anterior descending (LAD, circumflex (LCX and right coronary artery (RCA. The main result was that corrected TFC in all coronaries was significantly increased in study patients compared to both control 1 and to control 2 patients. Study patients had hypertension or diabetes more often than control 1 patients. In conclusion, patients with CMR detected subendocardial ischemia have prolonged coronary blood flow. In connection with normal resting flow values in CAD, this supports the hypothesis of underlying coronary microvascular impairment. CMR stress perfusion differentiates non-invasively between this entity and relevant CAD.

  13. Comparison of gated SPECT, echocardiography and cardiac magnetic resonance imaging for the assessment of left ventricular ejection fraction and volumes

    International Nuclear Information System (INIS)

    Left ventricular ejection fraction (LVEF), end-diastolic volume (EDV) and end-systolic volume (ESV) can be determined non-invasively by two-dimensional echocardiography (ECHO), gated single photon emission computed tomography (GSPECT) and cardiac magnetic resonance imaging (CMRI). This study was designed to analyze the concordance between LVEF, EDV and ESV values derived from ECHO, GSPECT and CMRI. ECHO, GSPECT and CMRI were performed in a group of 21 patients with suspected coronary artery disease. LVEF, EDV and ESV values were calculated. The mean LVEF measured with GSPECT, ECHO and CMRI were 5.9+-17.8%, 55.7+-16.4% and 56.4+-15.7% respectively. The mean EDV measured with GSPECT, ECHO and CMRI were 109.2+-42.4 mL, 127.5+-42.2 mL and 91.1+-38.0 mL, respectively. The mean ESV measured with GSPECT, ECHO and CMRI were 54.2+-41.2 mL, 59.9+-37.6 mL, respectively. The results of liner regression analysis showed very good correlation between LVEF and ESV values derived from GSPECT, ECHO and CMRI (r=0.91, r=0.92, r=0.97 for LVEF and r=0.86, r=0.91, r=0.91 for ESV, P<0.091). Good correlation were found between EDV values obtained from GSPECT, ECHO and CMRI (r=0.71, r=0.68, r=0.73, P<0.01). Agreement between these techniques in LVEF values was also good, but not in LV volumes, according to Bland-Altman plots. This study showed good overall correlations between LVEF, EDV and ESV values derived from GSPECT, ECHO and LVEF obtained from any of these three imaging modalities could be used interchangeably. However, care should be taken in comparing LV volumes. (author)

  14. Regional heterogeneity in cardiac sympathetic innervation in acute myocardial infarction: relationship with myocardial oedema on magnetic resonance

    Energy Technology Data Exchange (ETDEWEB)

    Gimelli, Alessia; Masci, Pier Giorgio; Pasanisi, Emilio Maria; Lombardi, Massimo [Fondazione CNR/Regione Toscana, Pisa (Italy); Liga, Riccardo; Grigoratos, Chrysanthos [University Hospital of Pisa, Pisa (Italy); Marzullo, Paolo [Fondazione CNR/Regione Toscana, Pisa (Italy); Institute of Clinical Physiology, CNR, Pisa (Italy)

    2014-09-15

    To assess the relationships between myocardial structure and function on cardiac magnetic resonance (CMR) imaging and sympathetic tone on {sup 123}I-metaiodobenzylguanidine ({sup 123}I-MIBG) scintigraphy early after myocardial infarction (MI). Ten patients underwent {sup 123}I-MIBG and {sup 99m}Tc-tetrofosmin rest cadmium zinc telluride scintigraphy 4 ± 1 days after MI. The segmental left ventricular (LV) relative radiotracer uptake of both {sup 99m}Tc-tetrofosmin and early {sup 123}I-MIBG was calculated. The day after scintigraphy, on CMR imaging, the extent of ischaemia-related oedema and of myocardial fibrosis (late gadolinium enhancement, LGE) was assessed. Accordingly, the extent of oedema and LGE was evaluated for each segment and segmental wall thickening determined. Based on LGE distribution, LV segments were categorized as ''infarcted'' (56 segments), ''adjacent'' (66 segments) or ''remote'' (48 segments). Infarcted segments showed a more depressed systolic wall thickening and greater extent of oedema than adjacent segments (p < 0.001) and remote segments (p < 0.001). Interestingly, while uptake of {sup 99m}Tc-tetrofosmin was significantly depressed only in infarcted segments (p < 0.001 vs. both adjacent and remote segments), uptake of {sup 123}I-MIBG was impaired not only in infarcted segments (p < 0.001 vs. remote) but also in adjacent segments (p = 0.024 vs. remote segments). At the regional level, after correction for {sup 99m}Tc-tetrofosmin and LGE distribution, segmental {sup 123}I-MIBG uptake (p < 0.001) remained an independent predictor of ischaemia-related oedema. After acute MI the regional impairment of sympathetic tone extends beyond the area of altered myocardial perfusion and is associated with myocardial oedema. (orig.)

  15. Diffuse myocardial fibrosis evaluation using cardiac magnetic resonance T1 mapping: sample size considerations for clinical trials

    Directory of Open Access Journals (Sweden)

    Liu Songtao

    2012-12-01

    Full Text Available Abstract Background Cardiac magnetic resonance (CMR T1 mapping has been used to characterize myocardial diffuse fibrosis. The aim of this study is to determine the reproducibility and sample size of CMR fibrosis measurements that would be applicable in clinical trials. Methods A modified Look-Locker with inversion recovery (MOLLI sequence was used to determine myocardial T1 values pre-, and 12 and 25min post-administration of a gadolinium-based contrast agent at 3 Tesla. For 24 healthy subjects (8 men; 29 ± 6 years, two separate scans were obtained a with a bolus of 0.15mmol/kg of gadopentate dimeglumine and b 0.1mmol/kg of gadobenate dimeglumine, respectively, with averaged of 51 ± 34 days between two scans. Separately, 25 heart failure subjects (12 men; 63 ± 14 years, were evaluated after a bolus of 0.15mmol/kg of gadopentate dimeglumine. Myocardial partition coefficient (λ was calculated according to (ΔR1myocardium/ΔR1blood, and ECV was derived from λ by adjusting (1-hematocrit. Results Mean ECV and λ were both significantly higher in HF subjects than healthy (ECV: 0.287 ± 0.034 vs. 0.267 ± 0.028, p=0.002; λ: 0.481 ± 0.052 vs. 442 ± 0.037, p Conclusion ECV and λ quantification have a low variability across scans, and could be a viable tool for evaluating clinical trial outcome.

  16. Acute oedema in the evaluation of microvascular reperfusion and myocardial salvage in reperfused myocardial infarction with cardiac magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Phrommintikul, Arintaya, E-mail: apromint@mail.med.cmu.ac.t [Baker Heart Research Institute, Melbourne (Australia); Department of Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200 (Thailand); Abdel-Aty, Hassan, E-mail: hassan.abdel-sty@charite.d [Franz-Volhard-Klinik, Helios-Klinikum Berlin, Kardiologie, Charite Campus Berlin-Buch, Humboldt-Universitaet zu Berlin, Berlin (Germany); Department of Cardiac Sciences, Foothills Medical Centre, University of Calgary, 1403-29th Street NW, Calgary, Alberta (Canada); Schulz-Menger, Jeanette, E-mail: jeanette.schulz-menger@charite.d [Franz-Volhard-Klinik, Helios-Klinikum Berlin, Kardiologie, Charite Campus Berlin-Buch, Humboldt-Universitaet zu Berlin, Berlin (Germany); Friedrich, Matthias G., E-mail: matthias.friedrich@ucalgary.c [Franz-Volhard-Klinik, Helios-Klinikum Berlin, Kardiologie, Charite Campus Berlin-Buch, Humboldt-Universitaet zu Berlin, Berlin (Germany); Department of Cardiac Sciences, Foothills Medical Centre, University of Calgary, 1403-29th Street NW, Calgary, Alberta (Canada); Taylor, Andrew J., E-mail: andrew.taylor@baker.edu.a [Baker Heart Research Institute, Melbourne (Australia)

    2010-06-15

    The accurate measurement of myocardial salvage is critical to the ongoing refinement of reperfusion strategies in acute myocardial infarction (AMI). Cardiac magnetic resonance imaging (CMR) can define the area at risk in AMI by the presence of myocardial oedema, identified by high signal intensity on T{sub 2}-weighted imaging with a short inversion time inversion-recovery (STIR) sequence. In addition, myocardial necrosis can be identified with CMR delayed contrast enhanced imaging. In this prospective study we examined the relationship of acute oedema and necrosis with impaired microvascular reperfusion. We also evaluated acute oedema as a marker of the area at risk in AMI, for the purposes of documenting myocardial salvage. CMR was performed on 15 patients with (AMI), within 24 h of successful percutaneous coronary intervention (PCI). Left ventricular (LV) systolic dysfunction was defined by a systolic thickening <40% (severe <20%). Microvascular reperfusion was evaluated during the acute phase of contrast wash-in. CMR was repeated 3 months post-PCI to evaluate recovery of LV function and final infarct size. Myocardial salvage was defined as the percentage of the area at risk that was not infarcted on follow up CMR. There was a significant correlation between impaired microvascular reperfusion and the extent of segmental oedema (R = 0.363, P < 0.01), but not myocardial necrosis (R = 0.110, P > 0.5). The extent of myocardial salvage correlated with recovery of systolic function (R = 0.241, P < 0.05), which was strongest in LV segments with severely reduced systolic function (R = 0.422, P < 0.01). Conclusions: In acutely reperfused AMI, oedema can be used to identify the area at risk for the purpose of calculating myocardial salvage. The correlation between myocardial oedema and reperfusion status suggests a pathological role of acute oedema in the impairment of microvascular reperfusion.

  17. Age- and gender-specific differences in left and right ventricular cardiac function and mass determined by cine magnetic resonance imaging

    International Nuclear Information System (INIS)

    We examined possible age- and gender-specific differences in the function and mass of left (LV) and right (RV) ventricles in 36 healthy volunteers using cine gradient-recalled echo magnetic resonance imaging. Subjects were divided into four groups (nine men and nine women in each): men aged under 45 years (32 ± 7), women aged under 45 (27 ± 6), men aged over 45 (59 ± 8), and women aged over 45 (57 ± 9). Functional analysis of cardiac volume and mass and of LV wall motion was performed by manual segmentation of the endocardial and epicardial borders of the end-diastolic and end-systolic frame; both absolute and normalized (per square meter body surface area) values were evaluated. With age there was a significant decrease in both absolute and normalized LV and RV chamber volumes (EDV, ESV), while LV and RV masses remained unchanged. Gender-specific differences were found in cardiac mass and volume (for men and women, respectively: LV mass, 155 ± 18 and 110 ± 16 g; LV EDV, 118 ± 27 and 96 ± 21 ml; LV ESV, 40 ± 13 and 29 ± 9 ml; RV mass, 52 ± 10 and 39 ± 5 g; RV EDV, 131 ± 28 and 100 ± 23 ml; RV ESV, 53 ± 17 and 33 ± 15 ml). Normalization to body surface area eliminated differences in LV volumes but not those in LV mass, RV mass, or RV function. Functional parameters such as cardiac output and LV ejection fraction showed nonsignificant or only slight differences and were thus largely independent of age and gender. Intra- and interobserver variability ranged between 1.4 % and 5.9 % for all parameters. Cine magnetic resonance imaging thus shows age- and gender-specific differences in cardiac function, and therefore the evaluation of cardiac function in patients should consider age- and gender-matched normative values. (orig.)

  18. Effect of thyroid hormones on cardiac function, geometry, and oxidative metabolism assessed noninvasively by positron emission tomography and magnetic resonance imaging.

    Science.gov (United States)

    Bengel, F M; Nekolla, S G; Ibrahim, T; Weniger, C; Ziegler, S I; Schwaiger, M

    2000-05-01

    Thyroid hormones influence cardiac performance directly and indirectly via changes in peripheral circulation. Little, however, is known about the effect on myocardial oxidative metabolism and its relation to cardiac function and geometry. Patients with a history of thyroidectomy for thyroid cancer present a unique model to investigate the cardiac effects of hypothyroidism. Ten patients without heart disease were investigated in the hypothyroid state and again 4-6 weeks later under euthyroid conditions. Myocardial oxidative metabolism was measured by positron emission tomography with [11C]acetate and the clearance constant k(mono). Cine magnetic resonance imaging was applied to determine left ventricular geometry. A stroke work index (SWI = stroke volume x systolic blood pressure/ventricular mass) was calculated. Then, to estimate myocardial efficiency, a work metabolic index [WMI = SWI x heart rate/k(mono)] was obtained. Compared to hormone replacement, systemic vascular resistance and left ventricular mass were significantly higher in hypothyroidism. Ejection fraction and SWI were significantly lower. Despite an additional reduction of k(mono), the WMI was significantly lower, too. In summary, cardiac oxygen consumption is reduced in hypothyroidism. This reduction is associated with increased peripheral resistance and reduced contractility. Estimates of cardiac work are more severely suppressed than those of oxidative metabolism, suggesting decreased efficiency. These findings may provide an explanation for development or worsening of heart failure in hypothyroid patients with preexisting heart disease. PMID:10843159

  19. D-Dimer Levels Predict Myocardial Injury in ST-Segment Elevation Myocardial Infarction: A Cardiac Magnetic Resonance Imaging Study

    Science.gov (United States)

    Song, Young Bin; Lima, Joao A. C.; Guallar, Eliseo; Choe, Yeon Hyeon; Hwang, Jin Kyung; Kim, Eun Kyoung; Yang, Jeong Hoon; Hahn, Joo-Yong; Choi, Seung-Hyuk; Lee, Sang-Chol; Lee, Sang Hoon; Gwon, Hyeon-Cheol

    2016-01-01

    Objectives Elevated D-dimer levels on admission predict prognosis in patients undergoing primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI), but the association of D-dimer levels with structural markers of myocardial injury in these patients is unknown. Methods We performed cardiac magnetic resonance (CMR) imaging in 208 patients treated with primary PCI for STEMI. CMR was performed a median of 3 days after the index procedure. Of the 208 patients studied, 75 patients had D-dimer levels above the normal range on admission (>0.5 μg/mL; high D-dimer group) while 133 had normal levels (≤0.5 μg/mL; low D-dimer group). The primary outcome was myocardial infarct size assessed by CMR. Secondary outcomes included area at risk (AAR), microvascular obstruction (MVO) area, and myocardial salvage index (MSI). Results In CMR analysis, myocardial infarct size was larger in the high D-dimer group than in the low D-dimer group (22.3% [16.2–30.5] versus 18.8% [10.7–26.7]; p = 0.02). Compared to the low D-dimer group, the high D-dimer group also had a larger AAR (38.1% [31.7–46.9] versus 35.8% [24.2–45.3]; p = 0.04) and a smaller MSI (37.7 [28.2–46.9] versus 47.1 [33.2–57.0]; p = 0.01). In multivariate analysis, high D-dimer levels were significantly associated with larger myocardial infarct (OR 2.59; 95% CI 1.37–4.87; p<0.01) and lower MSI (OR 2.62; 95% CI 1.44–4.78; p<0.01). Conclusions In STEMI patients undergoing primary PCI, high D-dimer levels on admission were associated with a larger myocardial infarct size, a greater extent of AAR, and lower MSI, as assessed by CMR data. Elevated initial D-dimer level may be a marker of advanced myocardial injury in patients treated with primary PCI for STEMI. PMID:27513758

  20. Takotsubo cardiomyopathy, a two-stage recovery of left ventricular systolic and diastolic function as determined by cardiac magnetic resonance imaging

    DEFF Research Database (Denmark)

    Ahtarovski, Kiril Aleksov; Iversen, Kasper Karmark; Christensen, Thomas Emil;

    2014-01-01

    -12) 16 patients (mean age 66, range 39-84 years) diagnosed with TTC and 20 healthy matched controls. We performed cardiac magnetic resonance imaging (CMR) at admission, pre-discharge, and 3-month follow-up. Diastolic function was assessed by LV peak filling rate (LVPFR) and left atrial (LA) emptying...... imaging demonstrated non-coronary distributed apical oedema without contrast enhancement. CONCLUSION: Patients with TTC undergo fast systolic recovery. However, at discharge, profound diastolic dysfunction is demonstrated by CMR. At follow-up, both LV systolic and diastolic function is normalized in...

  1. Advanced echocardiography and cardiac magnetic resonance in congenital heart disease : insights in right ventricular mechanics and clinical implications

    NARCIS (Netherlands)

    Hulst, Anna Elisabeth van der

    2011-01-01

    The thesis provides new insights into advanced echocardiographic and magnetic resonance imaging techniques for comprehensive mechanical assessment of the right ventricle in healthy children and in pediatric patients with right ventricular dysfunction. It is shown that the right ventricle does not co

  2. 31P magnetic resonance spectroscopy to measure in vivo cardiac energetics in normal myocardium and hypertrophic cardiomyopathy: Experiences at 3 T

    International Nuclear Information System (INIS)

    Background: 31P magnetic resonance spectroscopy (MRS) allows measurement of in vivo high-energy phosphate kinetics in the myocardium. While traditionally 31P cardiac spectroscopy is performed at 1.5 T, cardiac MRS at higher field strength can theoretically increase signal to noise ratio (SNR) and spectral resolution therefore improving sensitivity and specificity of the cardiac spectra. The reproducibility and feasibility of performing cardiac spectroscopy at 3 T is presented here in this study in healthy volunteers and patients with hypertrophic cardiomyopathy. Methods: Cardiac spectroscopy was performed using a Phillips 3T Achieva scanner in 37 healthy volunteers and 26 patients with hypertrophic cardiomyopathy (HCM) to test the feasibility of the protocol. To test the reproducibility a single volunteer was scanned eight times on separate occasions. A single voxel 31P MRS was performed using Image Selected In vivo Spectroscopy (ISIS) volume localization. Results: The mean phosphocreatine/adenosine triphosphate (PCr/ATP) ratio of the eight measurements performed on one individual was 2.11 ± 0.25. Bland Altman plots showed a variance of 12% in the measurement of PCr/ATP ratios. The PCr/ATP ratio was significantly reduced in HCM patients compared to controls, 1.42 ± 0.51 and 2.11 ± 0.57, respectively, P 31P MRS at 3 T is a reliable method of measuring in vivo high-energy phosphate kinetics in the myocardium for clinical studies and diagnostics. Based on our data an impairment of cardiac energetic state in patients with hypertrophic cardiomyopathy is indisputable.

  3. Magnetic resonance imaging; Imagerie par resonance magnetique

    Energy Technology Data Exchange (ETDEWEB)

    Fontanel, F. [Centre Hospitalier, 40 - Mont-de -Marsan (France); Clerc, T. [Centre Hospitalier Universitaire, 76 - Rouen (France); Theolier, S. [Hospice Civils de Lyon, 69 - Lyon (France); Verdenet, J. [Centre Hospitalier Universitaire, 25 - Besancon (France)

    1997-04-01

    The last improvements in nuclear magnetic resonance imaging are detailed here, society by society with an expose of their different devices. In the future the different technological evolutions will be on a faster acquisition, allowing to reduce the examination time, on the development of a more acute cardiac imaging, of a functional neuro-imaging and an interactive imaging for intervention. With the contrast products, staying a longer time in the vascular area, the angiography will find its place. Finally, the studies on magnetic fields should allow to increase the volume to examine. (N.C.).

  4. Advanced echocardiography and cardiac magnetic resonance in congenital heart disease: insights in right ventricular mechanics and clinical implications

    OpenAIRE

    Hulst, Anna Elisabeth van der

    2011-01-01

    The thesis provides new insights into advanced echocardiographic and magnetic resonance imaging techniques for comprehensive mechanical assessment of the right ventricle in healthy children and in pediatric patients with right ventricular dysfunction. It is shown that the right ventricle does not contract synchronously in the longitudinal direction and that this is related to right ventricular function. Various echocardiographic (Tissue Doppler imaging, Speckle tracking, 3D echocardiography) ...

  5. Magnetic Resonance Imaging (MRI)

    Science.gov (United States)

    ... How Can I Help a Friend Who Cuts? Magnetic Resonance Imaging (MRI) KidsHealth > For Teens > Magnetic Resonance Imaging (MRI) Print A A A Text Size What's ... Exam Safety Getting Your Results What Is MRI? Magnetic resonance imaging (MRI) is a type of safe, painless testing ...

  6. Automation analysis of cardiac wall deformation from tagged magnetic resonance images; Analise automatica de deformacao do miocardio em imagens marcadas por ressonancia magnetica

    Energy Technology Data Exchange (ETDEWEB)

    Piva, R.M.V. [Hospital das Clinicas, Sao Paulo, SP (Brazil). Instituto do Coracao. Div. de Informatica; Kitney, R.I. [Imperial College of Science, Technology and Medicine, London (United Kingdom)

    1998-07-01

    Automation of cardiac wall deformation analysis from tagged magnetic resonance images (MRI) derives, basically, from the automatic detection of MR tags and left ventricle contours. In this work, it was adopted an approach based on image processing techniques and fuzzy logic to extract and classify image features as belonging to tags or ventricular borders. The use of fuzzy logic and IF-THEN rules, which involve image features such as length and curvature of valleys and gradients, allow the estimation of the membership of the pixels in the searched classes. The myocardial deformation is estimated in regions circumvented by contiguous tag intersections. The proposed method was applied to cine SPAMM (Spatial Modulation of Magnetization) short-axis images of the left ventricle obtained from human volunteers. (author)

  7. Cardiac magnetic resonance tomography in the diagnostics of restrictive and unclassified cardiopathies; Kardiale Magnetresonanztomographie in der Diagnostik der restriktiven und unklassifizierten Kardiomyopathien

    Energy Technology Data Exchange (ETDEWEB)

    Kramer, U.; Mangold, S.; Krumm, P.; Claussen, C.D. [Universitaet Tuebingen, Abteilung fuer Diagnostische und Interventionelle Radiologie, Radiologische Klinik, Tuebingen (Germany); May, A.E. [Universitaet Tuebingen, Medizinische Klinik III, Abteilung fuer Kardiologie und Kreislauferkrankungen, Tuebingen (Germany)

    2013-01-15

    Besides ischemic heart disease cardiomyopathies are common causes of heart failure and sudden cardiac death. The diagnostic spectrum in cardiomyopathies comprises non-invasive and invasive examination techniques. The exact verification of certain cardiomyopathies necessitates knowledge of the latest classification of cardiomyopathies as well as dedicated examination protocols. Modern imaging modalities, such as echocardiography and cardiac magnetic resonance imaging (MRI) have emerged as useful imaging tools in the investigation of patients suspected of having many different types of cardiomyopathies. Based on a better understanding of the underlying pathophysiology several diagnostic criteria have been defined using cardiac MRI. In particular there is an increasing importance of cardiac MRI in the description of patients with restrictive and unclassified cardiomyopathies. Echocardiography still remains the modality of choice in the diagnostics of unclear left ventricular heart failure. Further diagnostic work-up should include cardiac MRI in case of any lack of clarity. (orig.) [German] Kardiomyopathien stellen neben den ischaemischen Herzerkrankungen eine wesentliche Ursache fuer die Entwicklung einer Herzinsuffizienz und den ploetzlichen Herztod dar. Das diagnostische Spektrum bei Kardiomyopathien umfasst nichtinvasive und invasive Untersuchungsmethoden. Die exakte Diagnosesicherung einzelner Krankheitsbilder erfordert zum einen die Kenntnis der aktuellen Klassifikationen der heterogenen Gruppe der Kardiomyopathien, zum anderen sind oft spezielle Untersuchungstechniken erforderlich. Moderne bildgebende Verfahren stellen einen zentralen Bestandteil der diagnostischen Moeglichkeiten bei der Abklaerung einer Kardiomyopathie dar. Neben der Echokardiographie ist hier insbesondere die kardiale Magnetresonanztomographie (MRT) zu nennen. Mit zunehmendem Verstaendnis ueber die Pathogenese einzelner Kardiomyopathien konnten diagnostische Kriterien fuer die kardiale MRT

  8. Comparison of cardiac magnetic resonance imaging features of isolated left ventricular non-compaction in adults versus dilated cardiomyopathy in adults

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, H. [Department of Radiology, Cardiovascular Institute and Fuwai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037 (China); Zhao, S., E-mail: cjrzhaoshihua2009@163.com [Department of Radiology, Cardiovascular Institute and Fuwai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037 (China); Jiang, S.; Lu, M.; Yan, C.; Ling, J.; Zhang, Y.; Liu, Q.; Ma, N.; Yin, G.; Wan, J. [Department of Radiology, Cardiovascular Institute and Fuwai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037 (China); Yang, Y. [Department of Cardiology, Cardiovascular Institute and Fuwai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037 (China); Li, L. [Department of Pathology, Cardiovascular Institute and Fuwai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037 (China); Jerecic, R. [MR Research and Development, Siemens Medical Solutions, Chicago, IL (United States); He, Z. [Department of Nuclear Medicine, Cardiovascular Institute and Fuwai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037 (China)

    2011-09-15

    Aim: To compare cardiac magnetic resonance imaging (MRI) features between isolated left ventricular non-compaction (IVNC) and dilated cardiomyopathy (DCM) in adults. Materials and methods: A consecutive series of 50 patients with IVNC from a single institution were reviewed. During the same period, 50 patients with DCM who had prominent trabeculations, who were matched for age, gender, and body surface area, were prospectively included. Left ventricular (LV) morphology and function were assessed using cardiac MRI. Results: Compared with patients with DCM, patients with IVNC had a significantly lower LV sphericity index and end-diastolic volume index (LVEDVI) and a greater LV ejection fraction (LVEF), number of trabeculated segments, and ratio of non-compacted to compacted myocardium (NC/C ratio). There were no significant differences in stroke volume index, cardiac output, and cardiac index between the two patient groups. In patients with IVNC, the number of trabeculated segments and the NC/C ratio correlated positively with LVEDVI (r = 0.626 and r = 0.559, respectively) and negatively with LVEF (r = -0.647 and r = -0.521, respectively, p < 0.001 for all). In patients with DCM, the number of non-compacted segments and the NC/C ratio had no correlation with either the LVEDVI (r = -0.082 and r = -0.135, respectively) or the LVEF (r = 0.097 and r = 0.205, respectively). Conclusion: There are demonstrable morphological and functional differences between IVNC and DCM at LV assessment using cardiac MRI. The occurrence of trabeculated myocardium might be due to a different pathophysiological mechanism.

  9. Multimodality evaluation of ventricular function: comparison of cardiac magnetic resonance imaging, echocardiography, and planar and SPECT blood pool imaging

    Science.gov (United States)

    Feiglin, David H.; Krol, Andrzej; Tillapaugh-Fay, Gwen M.; Szeverenyi, Nikolaus M.; Thomas, Frank D.

    2001-05-01

    Fifteen patients underwent resting echocardiography (EC), ECG gated cardiac MR ventriculography (MRV) and blood pool planar and SPECT ventriculography (SPV) sequentially on the same day. In addition, 36 patients had sequential ECG gated blood pool and SPV and 20 normal volunteers, age > 18 years, had sequential ECG gated cardiac MRI performed on both Siemens closed, 1.5T, and open, 0.2T, magnets. Echocardiography was performed using a HP 5500 system equipped with an S4 transducer in 2D mode. MRV at 0.2T and 1.5T used a circular polarized body coil. Nuclear Medicine studies used 25 mCi Tc- 99m labeled red blood cells. Gated planar and SPV were acquired on a dual head Siemens E-Cam system. We have found that MRV affords the most accurate measurement of ventricular function. SPV and MRV provide similar estimations of left ventricular function (LVEF). Further, SPV consistently provides higher LVEF, as compared to the planar data simultaneously acquired. Observed significant differences in intermodality measurements indicate that follow up studies in patients, especially in patients whose management is critically dependent on functional measurement changes, should be monitored by one modality only.

  10. Quantification of myocardial perfusion using cardiac magnetic resonance imaging correlates significantly to rubidium-82 positron emission tomography in patients with severe coronary artery disease

    DEFF Research Database (Denmark)

    Qayyum, Abbas A; Hasbak, Philip; Larsson, Henrik B W;

    2014-01-01

    rest and adenosine stress imaging by 1.5-Tesla MR Scanner and a mCT/PET 64-slice Scanner. CMRI were analyzed based on Tikhonov's procedure of deconvolution without specifying an explicit compartment model using our own software. PET images were analyzed using standard clinical software. CMRI and PET......INTRODUCTION: Aim was to compare absolute myocardial perfusion using cardiac magnetic resonance imaging (CMRI) based on Tikhonov's procedure of deconvolution and rubidium-82 positron emission tomography (Rb-82 PET). MATERIALS AND METHODS: Fourteen patients with coronary artery stenosis underwent...... data was compared with Spearman's rho and Bland-Altman analysis. RESULTS: CMRI results were strongly and significantly correlated with PET results for the absolute global myocardial perfusion differences (r=0.805, p=0.001) and for global myocardial perfusion reserve (MPR) (r=0.886, p<0.001). At vessel...

  11. Value of cardiac magnetic resonance imaging in diagnosing coronary heart disease%心脏磁共振在冠心病诊断中的意义

    Institute of Scientific and Technical Information of China (English)

    赵世华

    2011-01-01

    @@ 心脏磁共振(cardiac magnetic resonance,CMR)扫描不仅无电离辐射,且与超声、CT及核素等常见的无创性检查相比,其空间和时间分辨率的组合堪称最佳.不仅如此,CMR具有大视野、多成像序列、高度的组织分辨力及不断呈现的新方法、新技术,能对心脏形态、功能、心肌灌注、血管造影、动脉斑块及分子显像等进行"一站式"检查.

  12. Influence of pre-infarction angina, collateral flow, and pre-procedural TIMI flow on myocardial salvage index by cardiac magnetic resonance in patients with ST-segment elevation myocardial infarction

    DEFF Research Database (Denmark)

    Lønborg, Jacob Thomsen; Kelbæk, Henning Skov; Vejlstrup, Niels Grove;

    2012-01-01

    salvage index (MSI) and infarct size adjusting for area at risk in patients with STEMI treated with primary percutaneous coronary intervention. METHODS AND RESULTS: Cardiac magnetic resonance (CMR) was used to measure myocardial area at risk within 1-7 days and final infarct size 90±21 days after the...

  13. Magnetic Resonance Imaging (MRI)

    Science.gov (United States)

    ... Resonance Imaging (MRI) What is an MRI? MRI stands for Magnetic Resonance Imaging. It is an important ... MRI is often used for diagnosis or for monitoring disease. For example, if someone is having severe ...

  14. NMRES: an artificial intelligence expert system for quantification of cardiac metabolites from 31phosphorus nuclear magnetic resonance spectroscopy.

    Science.gov (United States)

    Chow, J L; Levitt, K N; Kost, G J

    1993-01-01

    The application of high-resolution 31Phosphorus Nuclear Magnetic Resonance (31P NMR) Spectroscopy in biology and medicine has provided new insights into biochemical processes and also a unique assessment of metabolites. However, accurate quantification of biological NMR spectra is frequently complicated by: (a) non-Lorentzian form of peak lineshapes, (b) contamination of peak signals by neighboring peaks, (c) presence of broad resonances, (d) low signal-to-noise ratios, and (e) poorly defined sloping baselines. Our objectives were to develop an expert system that captures and formalizes 31P NMR spectroscopists' expert knowledge, and to provide a reliable, efficient, and automated system for the interpretation of biological spectra. The NMR Expert System (NMRES) was written in the C and OPS5 programming languages and implemented on a Unix-based (Ultrix) mainframe system with XWindows bit-map graphics display. Expert knowledge was acquired from NMR spectroscopists and represented as production rules in the knowledge base. A heuristic weights method was employed to determine the confidence levels of potential peaks. Statistical and numerical methods were used to facilitate processing decisions. NMR spectra obtained from studies of ischemic neonatal and immature hearts were used to assess the performance of the expert system. The expert system performed signal extraction, noise treatment, resonance assignment, intracellular pH determination, and metabolite intensity quantitation in about 10 s per 4 KB (kilobyte) spectrum. The peak identification success rate was 98.2%. Peak areas and pH estimated by the expert system compared favorably with those determined by human experts. We conclude that the expert system has provided a framework for reliable and efficient quantification of complex biological 31P NMR spectra. PMID:8328724

  15. Gated myocardial perfusion SPECT underestimates left ventricular volumes and shows high variability compared to cardiac magnetic resonance imaging -- a comparison of four different commercial automated software packages

    Directory of Open Access Journals (Sweden)

    Arheden Håkan

    2010-05-01

    Full Text Available Abstract Background We sought to compare quantification of left ventricular volumes and ejection fraction by different gated myocardial perfusion SPECT (MPS programs with each other and to magnetic resonance (MR imaging. Methods N = 100 patients with known or suspected coronary artery disease were examined at rest with 99 mTc-tetrofosmin gated MPS and cardiac MR imaging. Left ventricular end-diastolic volume (EDV, end-systolic volume (ESV, stroke volume (SV and ejection fraction (EF were obtained by analysing gated MPS data with four different programs: Quantitative Gated SPECT (QGS, GE MyoMetrix, Emory Cardiac Toolbox (ECTb and Exini heart. Results All programs showed a mean bias compared to MR imaging of approximately -30% for EDV (-22 to -34%, p Conclusions Gated MPS, systematically underestimates left ventricular volumes by approximately 30% and shows a high variability, especially for ESV. For EF, accuracy was better, with a mean bias between -15 and 6% of EF. It may be of value to take this into consideration when determining absolute values of LV volumes and EF in a clinical setting.

  16. Cardiac magnetic resonance imaging-derived pulmonary artery distensibility index correlates with pulmonary artery stiffness and predicts functional capacity in patients with pulmonary arterial hypertension

    International Nuclear Information System (INIS)

    Increased stiffness of the pulmonary vascular bed is known to increase mortality in patients with pulmonary arterial hypertension (PAH); and pulmonary artery (PA) stiffness is also thought to be associated with exercise capacity. The purpose of the present study was to investigate whether cardiac magnetic resonance imaging (CMRI)-derived PA distensibility index correlates with PA stiffness estimated on right heart catheterization (RHC) and predicts functional capacity (FC) in patients with PAH. Thirty-five consecutive PAH patients (23% male, mean age, 44±13 years; 69% idiopathic) underwent CMRI, RHC, and 6-min walk test (6MWT). PA distensibility indices were derived from cross-sectional area change (%) in the transverse view, perpendicular to the axis of the main PA, on CMRI [(maximum area-minimum area)/minimum area during cardiac cycle]. Among the PA stiffness indices, pulmonary vascular resistance (PVR) and PA capacitance were calculated using hemodynamic dataset from RHC. CMRI-derived PA distensibility was inversely correlated with PVR (R2=0.34, P2=0.35, P2=0.61, P<0.001). Furthermore, PA distensibility <20% predicted poor FC (<400 m in 6MWT) with a sensitivity of 82% and a specificity of 94%. Non-invasive CMRI-derived PA distensibility index correlates with PA stiffness and can predict FC in patients with PAH. (author)

  17. Aortic stiffness is associated with cardiac function and cerebral small vessel disease in patients with type 1 diabetes mellitus: assessment by magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Elderen, Saskia G.C. van; Brandts, A.; Westenberg, J.J.M.; Grond, J. van der; Buchem, M.A. van; Kroft, L.J.M.; Roos, A. de [Leiden University Medical Center, Department of Radiology, Leiden (Netherlands); Tamsma, J.T.; Romijn, J.A.; Smit, J.W.A. [Leiden University Medical Center, Department of Endocrinology, Leiden (Netherlands)

    2010-05-15

    To evaluate, with the use of magnetic resonance imaging (MRI), whether aortic pulse wave velocity (PWV) is associated with cardiac left ventricular (LV) function and mass as well as with cerebral small vessel disease in patients with type 1 diabetes mellitus (DM). We included 86 consecutive type 1 DM patients (49 male, mean age 46.9 {+-} 11.7 years) in a prospective, cross-sectional study. Exclusion criteria included aortic/heart disease and general MRI contra-indications. MRI of the aorta, heart and brain was performed for assessment of aortic PWV, as a marker of aortic stiffness, systolic LV function and mass, as well as for the presence of cerebral white matter hyperintensities (WMHs), microbleeds and lacunar infarcts. Multivariate linear or logistic regression was performed to analyse the association between aortic PWV and outcome parameters, with covariates defined as age, gender, mean arterial pressure, heart rate, BMI, smoking, DM duration and hypertension. Mean aortic PWV was 7.1 {+-} 2.5 m/s. Aortic PWV was independently associated with LV ejection fraction (ss= -0.406, P = 0.006), LV stroke volume (ss=-0.407, P = 0.001), LV cardiac output (ss= -0.458, P = 0.001), and with cerebral WMHs (P < 0.05). There were no independent associations between aortic stiffness and LV mass, cerebral microbleeds or lacunar infarcts. Aortic stiffness is independently associated with systolic LV function and cerebral WMHs in patients with type 1 DM. (orig.)

  18. Aortic stiffness is associated with cardiac function and cerebral small vessel disease in patients with type 1 diabetes mellitus: assessment by magnetic resonance imaging

    International Nuclear Information System (INIS)

    To evaluate, with the use of magnetic resonance imaging (MRI), whether aortic pulse wave velocity (PWV) is associated with cardiac left ventricular (LV) function and mass as well as with cerebral small vessel disease in patients with type 1 diabetes mellitus (DM). We included 86 consecutive type 1 DM patients (49 male, mean age 46.9 ± 11.7 years) in a prospective, cross-sectional study. Exclusion criteria included aortic/heart disease and general MRI contra-indications. MRI of the aorta, heart and brain was performed for assessment of aortic PWV, as a marker of aortic stiffness, systolic LV function and mass, as well as for the presence of cerebral white matter hyperintensities (WMHs), microbleeds and lacunar infarcts. Multivariate linear or logistic regression was performed to analyse the association between aortic PWV and outcome parameters, with covariates defined as age, gender, mean arterial pressure, heart rate, BMI, smoking, DM duration and hypertension. Mean aortic PWV was 7.1 ± 2.5 m/s. Aortic PWV was independently associated with LV ejection fraction (ss= -0.406, P = 0.006), LV stroke volume (ss=-0.407, P = 0.001), LV cardiac output (ss= -0.458, P = 0.001), and with cerebral WMHs (P < 0.05). There were no independent associations between aortic stiffness and LV mass, cerebral microbleeds or lacunar infarcts. Aortic stiffness is independently associated with systolic LV function and cerebral WMHs in patients with type 1 DM. (orig.)

  19. Comparison of 18F-fluorodeoxyglucose positron emission tomography (FDG PET) and cardiac magnetic resonance (CMR) in corticosteroid-naive patients with conduction system disease due to cardiac sarcoidosis

    International Nuclear Information System (INIS)

    Cardiac sarcoidosis (CS) is a cause of conduction system disease (CSD). 18F-Fluorodeoxyglucose-positron emission tomography (FDG PET) and cardiac magnetic resonance (CMR) are used for detection of CS. The relative diagnostic value of these has not been well studied. The aim was to compare these imaging modalities in this population. We recruited steroid-naive patients with newly diagnosed CSD due to CS. All CS patients underwent both imaging studies within 12 weeks of each other. Patients were classified into two groups: group A with chronic mild CSD (right bundle branch block and/or axis deviation), and group B with new-onset atrioventricular block (AVB, Mobitz type II or third-degree AVB). Thirty patients were included. Positive findings on both imaging studies were seen in 72 % of patients (13/18) in group A and in 58 % of patients (7/12) in group B. The remainder (28 %) of the patients in group A were positive only on CMR. Of the patients in group B, 8 % were positive only on CMR and 33 % were positive only on FDG PET. Patients in group A were more likely to be positive only on CMR, and patients in group B were more likely to be positive only on FDG PET (p = 0.02). Patients in group B positive only on FDG PET underwent CMR earlier relative to their symptomatology than patients positive only on CMR (median 7.0, IQR 1.5 - 34.3, vs. 72.0, IQR 25.0 - 79.5 days; p = 0.03). The number of positive FDG PET and CMR studies was different in patients with CSD depending on their clinical presentation. This study demonstrated that CMR can adequately detect cardiac involvement associated with chronic mild CSD. In patients presenting with new-onset AVB and a negative CMR study, FDG PET may be useful for detecting cardiac involvement due to CS. (orig.)

  20. Comparison of {sup 18}F-fluorodeoxyglucose positron emission tomography (FDG PET) and cardiac magnetic resonance (CMR) in corticosteroid-naive patients with conduction system disease due to cardiac sarcoidosis

    Energy Technology Data Exchange (ETDEWEB)

    Ohira, Hiroshi; Birnie, David H.; Mc Ardle, Brian; Dick, Alexander; Klein, Ran; Renaud, Jennifer; DeKemp, Robert A.; Davies, Ross; Hessian, Renee; Liu, Peter; Nery, Pablo B. [University of Ottawa Heart Institute, Molecular Function and Imaging Program, National Cardiac PET Centre, Ottawa, ON (Canada); University of Ottawa Heart Institute, Arrhythmia Service, Division of Cardiology, Department of Medicine, Ottawa, ON (Canada); Pena, Elena; Dennie, Carole [The Ottawa Hospital, Medical Imaging Department, Ottawa, ON (Canada); University of Ottawa, Department of Radiology, Ottawa, ON (Canada); Bernick, Jordan; Wells, George A. [University of Ottawa Heart Institute, Cardiovascular Research Methods Center, Ottawa, ON (Canada); Leung, Eugene [The Ottawa Hospital, Division of Nuclear Medicine, Department of Medicine, Ottawa, Ontario (Canada); Yoshinaga, Keiichiro [Hokkaido University School of Medicine, Department of Molecular Imaging, Hokkaido (Japan); Tsujino, Ichizo; Sato, Takahiro; Nishimura, Masaharu [Hokkaido University School of Medicine, First Department of Medicine, Hokkaido (Japan); Manabe, Osamu; Tamaki, Nagara [Hokkaido University School of Medicine, Department of Nuclear Medicine, Hokkaido (Japan); Oyama-Manabe, Noriko [Hokkaido University Hospital, Diagnostic and Interventional Radiology, Hokkaido (Japan); Ruddy, Terrence D.; Beanlands, Rob S.B. [University of Ottawa Heart Institute, Molecular Function and Imaging Program, National Cardiac PET Centre, Ottawa, ON (Canada); University of Ottawa Heart Institute, Arrhythmia Service, Division of Cardiology, Department of Medicine, Ottawa, ON (Canada); The Ottawa Hospital, Medical Imaging Department, Ottawa, ON (Canada); University of Ottawa, Department of Radiology, Ottawa, ON (Canada); The Ottawa Hospital, Division of Nuclear Medicine, Department of Medicine, Ottawa, Ontario (Canada); Chow, Benjamin J.W. [University of Ottawa Heart Institute, Molecular Function and Imaging Program, National Cardiac PET Centre, Ottawa, ON (Canada); University of Ottawa Heart Institute, Arrhythmia Service, Division of Cardiology, Department of Medicine, Ottawa, ON (Canada); The Ottawa Hospital, Medical Imaging Department, Ottawa, ON (Canada); University of Ottawa, Department of Radiology, Ottawa, ON (Canada)

    2016-02-15

    Cardiac sarcoidosis (CS) is a cause of conduction system disease (CSD). {sup 18}F-Fluorodeoxyglucose-positron emission tomography (FDG PET) and cardiac magnetic resonance (CMR) are used for detection of CS. The relative diagnostic value of these has not been well studied. The aim was to compare these imaging modalities in this population. We recruited steroid-naive patients with newly diagnosed CSD due to CS. All CS patients underwent both imaging studies within 12 weeks of each other. Patients were classified into two groups: group A with chronic mild CSD (right bundle branch block and/or axis deviation), and group B with new-onset atrioventricular block (AVB, Mobitz type II or third-degree AVB). Thirty patients were included. Positive findings on both imaging studies were seen in 72 % of patients (13/18) in group A and in 58 % of patients (7/12) in group B. The remainder (28 %) of the patients in group A were positive only on CMR. Of the patients in group B, 8 % were positive only on CMR and 33 % were positive only on FDG PET. Patients in group A were more likely to be positive only on CMR, and patients in group B were more likely to be positive only on FDG PET (p = 0.02). Patients in group B positive only on FDG PET underwent CMR earlier relative to their symptomatology than patients positive only on CMR (median 7.0, IQR 1.5 - 34.3, vs. 72.0, IQR 25.0 - 79.5 days; p = 0.03). The number of positive FDG PET and CMR studies was different in patients with CSD depending on their clinical presentation. This study demonstrated that CMR can adequately detect cardiac involvement associated with chronic mild CSD. In patients presenting with new-onset AVB and a negative CMR study, FDG PET may be useful for detecting cardiac involvement due to CS. (orig.)

  1. Macrophage Uptake of Ultra-Small Iron Oxide Particles for Magnetic Resonance Imaging in Experimental Acute Cardiac Transplant Rejection

    International Nuclear Information System (INIS)

    Purpose: To discriminate between acutely rejecting and non-rejecting transplanted hearts using a blood pool contrast agent and T2 magnetic resonance imaging (MRI) in a clinical 1.5T scanner. Material and Methods: Allogeneic and syngeneic heterotopic heart transplantations were performed in rats. One allogeneic and one syngeneic group each received either the ultra-small iron oxide particle (USPIO), at two different doses, or no contrast agent at all. MRI was performed on postoperative day 6. Immediately after the MR scanning, contrast agent was injected and a further MRI was done 24 h later. Change in T2 was calculated. Results: No significant difference in change in T2 could be seen between rejecting and non-rejecting grafts in either of the doses, or in the control groups. There was a difference between the allogeneic group that received the higher contrast agent dose and the allogeneic group that did not receive any contrast agent at all. Conclusion: In our rat model, measurements of T2 after myocardial macrophage uptake of AMI-227 in a clinical 1.5T scanner were not useful for the diagnosis of acute rejection

  2. High-resolution numerical simulation of Left Ventricular Hemodynamics Guided by in-vivo Cardiac Magnetic Resonance Data

    Science.gov (United States)

    Le, Trung; Sotiropoulos, Fotis; Mirabella, Lucia; Chaffins, Brandon; Santhanakrishnan, Arvind; Oshinski, John; Yoganathan, Ajit; University of Minnesota Collaboration; Georgia Institute of Technology Collaboration

    2012-11-01

    We study the fluid dynamics within a patient-specific left ventricle (LV) during diastole using both numerical simulations and in-vivo data. The kinematics of the LV is reconstructed from high-resolution Magnetic Resonance Imaging (MRI) data acquired on a healthy volunteer, using image segmentation and a surface registration process. The flow velocity is acquired using phase-contrast MRI at the mitral orifice and at an additional parallel plane inside the ventricle. Numerical simulations are carried out using the CURVIB method (Ge et al., JCP, 2007) with the MRI reconstructed LV wall motion imposed as boundary condition. The numerical simulations show the highly dynamic environment of the flow field. The mitral vortex ring is formed during early diastolic filling and breaks down into small scale structures. The simulated hemodynamics are compared with phase-contrast MRI measurements and previous simulations in which the LV wall motion was obtained from a lumped parameter model (Le and Sotiropoulos, Eur. J. Mechanics B - Fluids, 2012). We acknowlege NIH Grant RO1-HL-07262 and the Minnesota Supercomputing Institute support.

  3. Macrophage Uptake of Ultra-Small Iron Oxide Particles for Magnetic Resonance Imaging in Experimental Acute Cardiac Transplant Rejection

    Energy Technology Data Exchange (ETDEWEB)

    Penno, E.; Johnsson, C.; Johansson, L.; Ahlstroem, H. [Uppsala Univ. Hospital (Sweden). Depts. of Diagnostic Radiology and of Transplantation Surgery

    2006-04-15

    Purpose: To discriminate between acutely rejecting and non-rejecting transplanted hearts using a blood pool contrast agent and T2 magnetic resonance imaging (MRI) in a clinical 1.5T scanner. Material and Methods: Allogeneic and syngeneic heterotopic heart transplantations were performed in rats. One allogeneic and one syngeneic group each received either the ultra-small iron oxide particle (USPIO), at two different doses, or no contrast agent at all. MRI was performed on postoperative day 6. Immediately after the MR scanning, contrast agent was injected and a further MRI was done 24 h later. Change in T2 was calculated. Results: No significant difference in change in T2 could be seen between rejecting and non-rejecting grafts in either of the doses, or in the control groups. There was a difference between the allogeneic group that received the higher contrast agent dose and the allogeneic group that did not receive any contrast agent at all. Conclusion: In our rat model, measurements of T2 after myocardial macrophage uptake of AMI-227 in a clinical 1.5T scanner were not useful for the diagnosis of acute rejection.

  4. Assessment of cardiac remodeling in asymptomatic mitral regurgitation for surgery timing: a comparative study of echocardiography and magnetic resonance imaging

    Directory of Open Access Journals (Sweden)

    Ozdogan Oner

    2010-08-01

    Full Text Available Abstract Background Early surgery is recommended for asymptomatic severe mitral regurgitation (MR, because of increased postoperative left ventricular (LV dysfunction in patients with late surgery. On the other hand, recent reports emphasized a "watchful waiting" process for the determination of the proper time of mitral valve surgery. In our study, we compared magnetic resonance imaging (MRI and transthoracic echocardiography to evaluate the LV and left atrial (LA remodeling; for better definitions of patients that may benefit from early valve surgery. Methods Twenty-one patients with moderate to severe asymptomatic MR were evaluated by echocardiography and MRI. LA and LV ejection fractions (EFs were calculated by echocardiography and MRI. Pulmonary veins (PVs were measured from vein orifices in diastole and systole from the tangential of an imaginary circle that completed LA wall. Right upper PV indices were calculated with the formula; (Right upper PV diastolic diameter- Right upper PV systolic diameter/Right upper PV diastolic diameter. Results In 9 patients there were mismatches between echocardiography and MRI measurements of LV EF. LV EFs were calculated ≥60% by echocardiography, meanwhile 0.05. However, both right upper PV indices (0.16 ± 0.06 vs. 0.24 ± 0.08, p: 0.024 and LA EFs (0.19 ± 0.09 vs. 0.33 ± 0.14, p: 0.025 were significantly decreased in patients with depressed EFs when compared to patients with normal EFs. Conclusions MRI might be preferred when small changes in functional parameters like LV EF, LA EF, and PV index are of clinical importance to disease management like asymptomatic MR patients that we follow up for appropriate surgery timing.

  5. Atherosclerotic renal artery stenosis is prevalent in cardiorenal patients but not associated with left ventricular function and myocardial fibrosis as assessed by cardiac magnetic resonance imaging

    Directory of Open Access Journals (Sweden)

    Emans Mireille E

    2012-09-01

    Full Text Available Abstract Background Atherosclerotic renal artery stenosis (ARAS is common in cardiovascular diseases and associated with hypertension, renal dysfunction and/or heart failure. There is a paucity of data about the prevalence and the role of ARAS in the pathophysiology of combined chronic heart failure (CHF and chronic kidney disease (CKD. We investigated the prevalence in patients with combined CHF/CKD and its association with renal function, cardiac dysfunction and the presence and extent of myocardial fibrosis. Methods The EPOCARES study (ClinTrialsNCT00356733 investigates the role of erythropoietin in anaemic patients with combined CHF/CKD. Eligible subjects underwent combined cardiac magnetic resonance imaging (cMRI, including late gadolinium enhancement, with magnetic resonance angiography of the renal arteries (MRA. Results MR study was performed in 37 patients (median age 74 years, eGFR 37.4 ± 15.6 ml/min, left ventricular ejection fraction (LVEF 43.3 ± 11.2%, of which 21 (56.8% had ARAS (defined as stenosis >50%. Of these 21 subjects, 8 (21.6% had more severe ARAS >70% and 8 (21.6% had a bilateral ARAS >50% (or previous bilateral PTA. There were no differences in age, NT-proBNP levels and medication profile between patients with ARAS versus those without. Renal function declined with the severity of ARAS (p = 0.03, although this was not significantly different between patients with ARAS versus those without. Diabetes mellitus was more prevalent in patients without ARAS (56.3% against those with ARAS (23.8% (p = 0.04. The presence and extent of late gadolinium enhancement, depicting myocardial fibrosis, did not differ (p = 0.80, nor did end diastolic volume (p = 0.60, left ventricular mass index (p = 0.11 or LVEF (p = 0.15. Neither was there a difference in the presence of an ischemic pattern of late enhancement in patients with ARAS versus those without. Conclusions ARAS is prevalent in combined CHF

  6. Stenosis of the branches of the neopulmonary artery after the arterial switch operation: A cardiac magnetic resonance imaging study

    Directory of Open Access Journals (Sweden)

    Boban Thomas

    2013-01-01

    Conclusions: Cardiac MR can be used as a comprehensive non-invasive imaging technique to diagnose stenosis of the branches of the neopulmonary after the ASO, allowing evaluation of anatomy and function of the neoPA, its branches, and the differential perfusion to each lung, thus facilitating clinical decision making.

  7. Churg-Strauss syndrome cardiac involvement evaluated by cardiac magnetic resonance imaging and positron-emission tomography: a prospective study on 20 patients

    International Nuclear Information System (INIS)

    Churg-Strauss syndrome (CSS) cardiac involvement is associated with a poor prognosis. Recently cardiac MRI (CMRI) has emerged as a promising technique to detect early CSS cardiac involvement. However, CMRI-detected myocardial delayed enhancement (MDE) could correspond to fibrosis or inflammation. Fluoro-2-deoxyglucose PET (FDG-PET) was previously used in other systemic diseases to distinguish between them. To determine whether the CMRI-MDE detected in CSS patients reflected fibrosis or myocardial inflammation, patients in CSS remission underwent FDG-PET. Twenty consecutive CSS patients in remission (BVAS = 0) were recruited. Fourteen patients [eight men, six women; mean (S.D.) age 49 (9) years; mean disease duration 3.5 (2.9) years] with CMRI-detected MDE, and six patients [four men, two women; mean (S.D.) age 44 (15) years; mean disease duration 3.5 (5.3) years] with normal CMRI underwent FDG-PET. Segments with MDE on CMRI were analysed on FDG-PET images, with myocardial FDG hypo-fixation defining fibrosis and hyper-fixation corresponding inflammation. Among the 14 patients with MDE on CMRI, FDG-PET showed 10 had hypo-fixation, 2 had hyper-fixation and 2 had normal scans. CSS duration at the time of CMRI was shorter for patients with myocardial inflammation than in those with fibrosis. The six patients with normal CMRI had normal FDG-PET images. For CSS patients in remission, CMRI detected subclinical active myocardial lesions and could be recommended to assess cardiac involvement. However, because CMRI-detected MDE can reflect fibrosis or inflammation, FDG-PET might help to distinguish between the two. (authors)

  8. Acute Response of Right Ventricular Function to Iloprost Inhalations in Patients with Pulmonary Arterial Hypertension: Preliminary Evaluation 
with Cardiac Magnetic Resonance Imaging

    Directory of Open Access Journals (Sweden)

    Qingqing LU

    2015-03-01

    Full Text Available Background and objective Pulmonary arterial hypertension (PAH is a progressive disorder characterized by abnormally elevated blood pressure of the pulmonary circulation. Without treatment, PAH progresses rapidly to right ventricular (RV failure and even death. Cardiac magnetic resonance imaging (CMRI has been an accurate and reproducible tool to assessment of RV morphology and function, which are important factors in the prognosis of patients with PAH. The aim of this study is to investigate acute RV response to inhalation of aerosolized iloprost in patients with PAH using CMRI. Method From March 2012 to March 2014, 48 patients with PAH underwent CMRI before and immediately after inhalation of iloprost with a single dose of 20 μg over 15 min-20 min. RV function parameters derived from CMRI images were analyzed before and after iloprost inhalation, including end-diastolic volume (EDV, end-diastolic area (EDA, end-systolic volume (ESV, end-systolic area (ESA, stroke volume (SV, ejection fraction (EF and cardiac output (CO. Percentage of RV area change was also calculated [%RVAC=(EDA-ESA/EDA×100%]. Wilcoxon's Sign Rank Test or Paired Samples t-Test was used to compare the differences of RV function parameters before and after inhalation. Results After iloprost inhalation, all patients showed significant decrease in RV EDV and RV ESV (P=0.007, P<0.001 respectively. Whereas, there were significant increase in RV SV (P=0.014, RV EF (P=0.009 and %RVAC (P=0.006. RV CO had no significant difference before and after inhalation (P=0.851. Conclusions Inhalation of iloprost can immediately improve RV function in patients with PAH, and noninvasive evaluation of the acute response with CMRI is feasibility.

  9. Major prognostic impact of persistent microvascular obstruction as assessed by contrast-enhanced cardiac magnetic resonance in reperfused acute myocardial infarction

    International Nuclear Information System (INIS)

    The aim of this study was to compare the prognostic significance of microvascular obstruction (MO) and persistent microvascular obstruction (PMO) as assessed by cardiac magnetic resonance (CMR) in patients with acute myocardial infarction (AMI). CMR was performed in 184 patients within the week following successfully reperfused first AMI. First-pass images were performed to evaluate extent of MO and late gadolinium-enhanced images to assess PMO and infarct size (IS). Major adverse cardiac events (MACE) were collected at 1-year follow-up. MO and PMO were found in 127 (69%) and 87 (47%) patients, respectively. By using univariate logistic regression analysis, high Global Registry of Acute Coronary Events (GRACE) risk score (odds ratio [OR] 95% confidence interval [CI]: 3.6 [1.8-7.4], p < 0.001), IS greater than 10% (OR [95% CI]: 2.7 [1.1-6.9], p = 0.036), left ventricular ejection fraction less than 40% (OR [95% CI]: 2.4 [1.1-5.2], p = 0.027), presence of MO (OR [95% CI]: 3.1 [1.3-7.3], p = 0.004) and presence of PMO (OR [95% CI]:10 [4.1-23.9], p < 0.001) were shown to be significantly associated with the outcome. By using multivariate analysis, presence of MO (OR [95% CI]: 2.5 [1.0-6.2], p = 0.045) or of PMO (OR [95% CI]: 8.7 [3.6-21.1], p < 0.001), associated with GRACE score, were predictors of MACE. Presence of microvascular obstruction and persistent microvascular obstruction is very common in AMI patients even after successful reperfusion and is associated with a dramatically higher risk of subsequent cardiovascular events, beyond established prognostic markers. Moreover, our data suggest that the prognostic impact of PMO might be superior to MO. (orig.)

  10. Magnetic Resonance Imaging and Magnetic Resonance Spectroscopy in Dementias

    OpenAIRE

    Hsu, Yuan-Yu; Du, An-Tao; Schuff, Norbert; Weiner, Michael W.

    2001-01-01

    This article reviews recent studies of magnetic resonance imaging and magnetic resonance spectroscopy in dementia, including Alzheimer's disease, frontotemporal dementia, dementia with Lewy bodies, idiopathic Parkinson's disease, Huntington's disease, and vascular dementia. Magnetic resonance imaging and magnetic resonance spectroscopy can detect structural alteration and biochemical abnormalities in the brain of demented subjects and may help in the differential diagnosis and early detection...

  11. Efficient isotropic magnetic resonators

    OpenAIRE

    Martin, O. J. F.; Gay-Balmaz, P.

    2002-01-01

    We study experimentally and numerically a novel three-dimensional magnetic resonator structure with high isotropy. It is formed by crossed split-ring resonators and has a response independent of the illumination direction in a specific plane. The utilization of such elements to build a finite left-handed medium is discussed. (C) 2002 American Institute of Physics.

  12. Magnetic resonance elastography as a method for the assessment of effective myocardial stiffness throughout the cardiac cycle.

    Science.gov (United States)

    Kolipaka, Arunark; Araoz, Philip A; McGee, Kiaran P; Manduca, Armando; Ehman, Richard L

    2010-09-01

    MR elastography (MRE) is a noninvasive technique in which images of externally generated waves propagating in tissue are used to measure stiffness. The first aim is to determine, from a range of driver configurations, the optimal driver for the purpose of generating waves within the heart in vivo. The second aim is to quantify the shear stiffness of normal myocardium throughout the cardiac cycle using MRE and to compare MRE stiffness to left ventricular chamber pressure in an in vivo pig model. MRE was performed in six pigs with six different driver setups, including no motion, three noninvasive drivers, and two invasive drivers. MRE wave displacement amplitudes were calculated for each driver. During the same MRI examination, left ventricular pressure and MRI-measured left ventricular volume were obtained, and MRE myocardial stiffness was calculated for 20 phases of the cardiac cycle. No discernible waves were imaged when no external motion was applied, and a single pneumatic drum driver produced higher amplitude waves than the other noninvasive drivers (P < 0.05). Pressure-volume loops overlaid onto stiffness-volume loops showed good visual agreement. Pressure and MRE-measured effective stiffness showed good correlation (R(2) = 0.84). MRE shows potential as a noninvasive method for estimating effective myocardial stiffness throughout the cardiac cycle. PMID:20578052

  13. Manual correction of semi-automatic three-dimensional echocardiography is needed for right ventricular assessment in adults; validation with cardiac magnetic resonance

    Directory of Open Access Journals (Sweden)

    Ostenfeld Ellen

    2012-01-01

    Full Text Available Abstract Background Three-dimensional echocardiography (3DE and semi-automatic right ventricular delineation has been proposed as an appropriate method for right ventricle (RV evaluation. We aimed to examine how manual correction of semi-automatic delineation influences the accuracy of 3DE for RV volumes and function in a clinical adult setting using cardiac magnetic resonance (CMR as the reference method. We also examined the feasibility of RV visualization with 3DE. Methods 62 non-selected patients were examined with 3DE (Sonos 7500 and iE33 and with CMR (1.5T. Endocardial RV contours of 3DE-images were semi-automatically assessed and manually corrected in all patients. End-diastolic (EDV, end-systolic (ESV volumes, stroke volume (SV and ejection fraction (EF were computed. Results 53 patients (85% had 3DE-images feasible for examination. Correlation coefficients and Bland Altman biases between 3DE with manual correction and CMR were r = 0.78, -22 ± 27 mL for EDV, r = 0.83, -7 ± 16 mL for ESV, r = 0.60, -12 ± 18 mL for SV and r = 0.60, -2 ± 8% for EF (p Conclusion Manual correction of the 3DE semi-automatic RV delineation decreases the bias and is needed for acceptable clinical accuracy. 3DE is highly feasible for visualizing the RV in an adult clinical setting.

  14. Plaque vulnerability of coronary artery lesions is related to left ventricular dilatation as determined by optical coherence tomography and cardiac magnetic resonance imaging in patients with type 2 diabetes

    OpenAIRE

    Burgmaier, Mathias; Frick, Michael; Liberman, Ana; Battermann, Simone; Hellmich, Martin; Lehmacher, Walter; Jaskolka, Agnes; Marx, Nikolaus; Reith, Sebastian Berthold

    2013-01-01

    Background Patients with type 2 diabetes are at increased risk for both, left ventricular (LV)-dilatation and myocardial infarction (MI) following the rupture of a vulnerable plaque. This study investigated the to date incompletely understood relationship between plaque vulnerability and LV-dilatation using optical coherence tomography (OCT) and cardiac magnetic resonance imaging (CMR) in patients with type 2 diabetes and stable coronary artery disease. Methods CMR was performed in 58 patient...

  15. 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...

  16. Cardiac effects of 3 months treatment of acromegaly evaluated by magnetic resonance imaging and B-type natriuretic peptides

    DEFF Research Database (Denmark)

    Andreassen, Mikkel; Faber, Jens; Kjær, Andreas;

    2010-01-01

    Long-term treatment of acromegaly prevents aggravation and reverses associated heart disease. A previous study has shown a temporary increase in serum levels of the N-terminal fraction of pro B-type natriuretic peptide (NT-proBNP) suggesting an initial decline in cardiac function when treatment of...... NT-proBNP). CMRI was performed at baseline and after 3 months of treatment. Levels of IGF-I, BNP and NT-proBNP were measured after 0, 1, 2 and 3 months. Eight patients (5 males and 3 females, mean age 53 ± 12 years (range 30-70)) and 8 matched healthy control subjects were included. Median IGF-I Z...

  17. Quantitative description of the 3D regional mechanics of the left atrium using cardiac magnetic resonance imaging

    International Nuclear Information System (INIS)

    The left atrium (LA) plays an important role in the maintenance of hemodynamic and electrical stability of the heart. One of the conditions altering the atrial mechanical function is atrial fibrillation (AF), leading to an increased thromboembolic risk due to impaired mechanical function. Preserving the regions of the LA that contribute the greatest to atrial mechanical function during curative strategies for AF is important. The purpose of this study is to introduce a novel method of regional assessment of mechanical function of the LA. We used cardiac MRI to reconstruct the 3D geometry of the LA in nine control and nine patients with paroxysmal atrial fibrillation (PAF). Regional mechanical function of the LA in pre-defined segments of the atrium was calculated using regional ejection fraction and wall velocity. We found significantly greater mechanical function in anterior, septal and lateral segments as opposed to roof and posterior segments, as well as a significant decrease of mechanical function in the PAF group. We suggest that in order to minimize the impact of the AF treatment on global atrial mechanical function, damage related to therapeutic intervention, such as catheter ablation, in those areas should be minimized. (paper)

  18. 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.

  19. Clinical feasibility of a myocardial signal intensity threshold-based semi-automated cardiac magnetic resonance segmentation method

    Energy Technology Data Exchange (ETDEWEB)

    Varga-Szemes, Akos; Schoepf, U.J.; Suranyi, Pal; De Cecco, Carlo N.; Fox, Mary A. [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); Muscogiuri, Giuseppe [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); University of Rome ' ' Sapienza' ' , Department of Medical-Surgical Sciences and Translational Medicine, Rome (Italy); Wichmann, Julian L. [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); University Hospital Frankfurt, Department of Diagnostic and Interventional Radiology, Frankfurt (Germany); Cannao, Paola M. [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); University of Milan, Scuola di Specializzazione in Radiodiagnostica, Milan (Italy); Renker, Matthias [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); Kerckhoff Heart and Thorax Center, Bad Nauheim (Germany); Mangold, Stefanie [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); Eberhard-Karls University Tuebingen, Department of Diagnostic and Interventional Radiology, Tuebingen (Germany); Ruzsics, Balazs [Royal Liverpool and Broadgreen University Hospitals, Department of Cardiology, Liverpool (United Kingdom)

    2016-05-15

    To assess the accuracy and efficiency of a threshold-based, semi-automated cardiac MRI segmentation algorithm in comparison with conventional contour-based segmentation and aortic flow measurements. Short-axis cine images of 148 patients (55 ± 18 years, 81 men) were used to evaluate left ventricular (LV) volumes and mass (LVM) using conventional and threshold-based segmentations. Phase-contrast images were used to independently measure stroke volume (SV). LV parameters were evaluated by two independent readers. Evaluation times using the conventional and threshold-based methods were 8.4 ± 1.9 and 4.2 ± 1.3 min, respectively (P < 0.0001). LV parameters measured by the conventional and threshold-based methods, respectively, were end-diastolic volume (EDV) 146 ± 59 and 134 ± 53 ml; end-systolic volume (ESV) 64 ± 47 and 59 ± 46 ml; SV 82 ± 29 and 74 ± 28 ml (flow-based 74 ± 30 ml); ejection fraction (EF) 59 ± 16 and 58 ± 17 %; and LVM 141 ± 55 and 159 ± 58 g. Significant differences between the conventional and threshold-based methods were observed in EDV, ESV, and LVM measurements; SV from threshold-based and flow-based measurements were in agreement (P > 0.05) but were significantly different from conventional analysis (P < 0.05). Excellent inter-observer agreement was observed. Threshold-based LV segmentation provides improved accuracy and faster assessment compared to conventional contour-based methods. (orig.)

  20. Left ventricular wall thickness in patients with hypertrophic cardiomyopathy: a comparison between cardiac magnetic resonance imaging and echocardiography.

    Science.gov (United States)

    Corona-Villalobos, Celia P; Sorensen, Lars L; Pozios, Iraklis; Chu, Linda; Eng, John; Abraham, Maria Roselle; Abraham, Theodore P; Kamel, Ihab R; Zimmerman, Stefan L

    2016-06-01

    We assessed whether cardiac MRI (CMR) and echocardiography (echo) have significant differences measuring left ventricular (LV) wall thickness (WT) in hypertrophic cardiomyopathy (HCM) as performed in the clinical routine. Retrospectively identified, clinically diagnosed HCM patients with interventricular-septal (IVS) pattern hypertrophy who underwent CMR and echo within the same day were included. Left Ventricular WT was measured by CMR in two planes and compared to both echo and contrast echo (cecho). 72 subjects, mean age 50.7 ± 16.2 years, 68 % males. Interventricular septal WT by echo and CMR planes showed good to excellent correlation. However, measurements of the postero-lateral wall showed poor correlation. Bland-Altman plots showed greater maximal IVS WT by echo compared to CMR measurement [SAX = 1.7 mm (-5.8, 9.3); LVOT = 1.1 mm (-5.6, 7.8)]. Differences were smaller between cecho and CMR [SAX = 0.8 mm (-9.2, 10.8); LVOT = -0.2 mm (-10.0, 9.6)]. Severity of WT by quartiles showed greater differences between echo and SAX CMR WT compared to cecho. Echocardiography typically measures greater WT than CMR, with the largest differences in moderate to severe hypertrophy. Contrast echocardiography more closely approximates CMR measurements of WT. These findings have potential clinical implications for risk stratification of subjects with HCM. PMID:26896038

  1. Clinical feasibility of a myocardial signal intensity threshold-based semi-automated cardiac magnetic resonance segmentation method

    International Nuclear Information System (INIS)

    To assess the accuracy and efficiency of a threshold-based, semi-automated cardiac MRI segmentation algorithm in comparison with conventional contour-based segmentation and aortic flow measurements. Short-axis cine images of 148 patients (55 ± 18 years, 81 men) were used to evaluate left ventricular (LV) volumes and mass (LVM) using conventional and threshold-based segmentations. Phase-contrast images were used to independently measure stroke volume (SV). LV parameters were evaluated by two independent readers. Evaluation times using the conventional and threshold-based methods were 8.4 ± 1.9 and 4.2 ± 1.3 min, respectively (P < 0.0001). LV parameters measured by the conventional and threshold-based methods, respectively, were end-diastolic volume (EDV) 146 ± 59 and 134 ± 53 ml; end-systolic volume (ESV) 64 ± 47 and 59 ± 46 ml; SV 82 ± 29 and 74 ± 28 ml (flow-based 74 ± 30 ml); ejection fraction (EF) 59 ± 16 and 58 ± 17 %; and LVM 141 ± 55 and 159 ± 58 g. Significant differences between the conventional and threshold-based methods were observed in EDV, ESV, and LVM measurements; SV from threshold-based and flow-based measurements were in agreement (P > 0.05) but were significantly different from conventional analysis (P < 0.05). Excellent inter-observer agreement was observed. Threshold-based LV segmentation provides improved accuracy and faster assessment compared to conventional contour-based methods. (orig.)

  2. Cardiac tissue engineering in magnetically actuated scaffolds

    International Nuclear Information System (INIS)

    Cardiac tissue engineering offers new possibilities for the functional and structural restoration of damaged or lost heart tissue by applying cardiac patches created in vitro. Engineering such functional cardiac patches is a complex mission, involving material design on the nano- and microscale as well as the application of biological cues and stimulation patterns to promote cell survival and organization into a functional cardiac tissue. Herein, we present a novel strategy for creating a functional cardiac patch by combining the use of a macroporous alginate scaffold impregnated with magnetically responsive nanoparticles (MNPs) and the application of external magnetic stimulation. Neonatal rat cardiac cells seeded within the magnetically responsive scaffolds and stimulated by an alternating magnetic field of 5 Hz developed into matured myocardial tissue characterized by anisotropically organized striated cardiac fibers, which preserved its features for longer times than non-stimulated constructs. A greater activation of AKT phosphorylation in cardiac cell constructs after applying a short-term (20 min) external magnetic field indicated the efficacy of magnetic stimulation to actuate at a distance and provided a possible mechanism for its action. Our results point to a synergistic effect of magnetic field stimulation together with nanoparticulate features of the scaffold surface as providing the regenerating environment for cardiac cells driving their organization into functionally mature tissue. (paper)

  3. Quantification of myocardial perfusion using cardiac magnetic resonance imaging correlates significantly to rubidium-82 positron emission tomography in patients with severe coronary artery disease: A preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Qayyum, Abbas A., E-mail: abbas.ali.qayyum@regionh.dk [Department of Cardiology and Cardiac Catheterization Laboratory 2014, The Heart Centre, Rigshospitalet, University Hospital of Copenhagen and Faculty of Health Sciences, Copenhagen University, Blegdamsvej 9, 2100 Copenhagen (Denmark); Hasbak, Philip, E-mail: philip.hasbak@regionh.dk [Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, University Hospital of Copenhagen and Faculty of Health Sciences, Copenhagen University, Blegdamsvej 9, 2100 Copenhagen (Denmark); Larsson, Henrik B.W., E-mail: henrik.larsson@regionh.dk [Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, University Hospital of Copenhagen and Faculty of Health Sciences, Copenhagen University, Blegdamsvej 9, 2100 Copenhagen (Denmark); Functional Imaging Unit, Diagnostic Department, Glostrup Hospital, University Hospital of Copenhagen and Faculty of Health Sciences, Copenhagen University, Ndr. Ringvej 57, 2600 Copenhagen (Denmark); Christensen, Thomas E., E-mail: thomas.emil.christensen@regionh.dk [Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, University Hospital of Copenhagen and Faculty of Health Sciences, Copenhagen University, Blegdamsvej 9, 2100 Copenhagen (Denmark); Ghotbi, Adam A., E-mail: adam.ali.ghotbi@regionh.dk [Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, University Hospital of Copenhagen and Faculty of Health Sciences, Copenhagen University, Blegdamsvej 9, 2100 Copenhagen (Denmark); Mathiasen, Anders B., E-mail: anders.b.mathiasen@gmail.com [Department of Cardiology and Cardiac Catheterization Laboratory 2014, The Heart Centre, Rigshospitalet, University Hospital of Copenhagen and Faculty of Health Sciences, Copenhagen University, Blegdamsvej 9, 2100 Copenhagen (Denmark); and others

    2014-07-15

    Introduction: Aim was to compare absolute myocardial perfusion using cardiac magnetic resonance imaging (CMRI) based on Tikhonov's procedure of deconvolution and rubidium-82 positron emission tomography (Rb-82 PET). Materials and methods: Fourteen patients with coronary artery stenosis underwent rest and adenosine stress imaging by 1.5-Tesla MR Scanner and a mCT/PET 64-slice Scanner. CMRI were analyzed based on Tikhonov's procedure of deconvolution without specifying an explicit compartment model using our own software. PET images were analyzed using standard clinical software. CMRI and PET data was compared with Spearman's rho and Bland–Altman analysis. Results: CMRI results were strongly and significantly correlated with PET results for the absolute global myocardial perfusion differences (r = 0.805, p = 0.001) and for global myocardial perfusion reserve (MPR) (r = 0.886, p < 0.001). At vessel territorial level, CMRI results were also significantly correlated with absolute PET myocardial perfusion differences (r = 0.737, p < 0.001) and MPR (r = 0.818, p < 0.001). Each vessel territory had similar strong correlation for absolute myocardial perfusion differences (right coronary artery (RCA): r = 0.787, p = 0.001; left anterior descending artery (LAD): r = 0.796, p = 0.001; left circumflex artery (LCX): r = 0.880, p < 0.001) and for MPR (RCA: r = 0.895, p < 0.001; LAD: r = 0.886, p < 0.001; LCX: r = 0.886, p < 0.001). Conclusion: On a global and vessel territorial basis, CMRI-measured absolute myocardial perfusion differences and MPR were strongly and significantly correlated with the Rb-82 PET findings.

  4. The Correlation between Left and Right Ventricular Ejection Fractions in Patients with Ischemic Heart Disease, Documented by Cardiac Magnetic Resonance Imaging

    Directory of Open Access Journals (Sweden)

    Ali Eshraghi

    2016-03-01

    Full Text Available Introduction: The correlation between right and left ventricular ejection fractions (RVEF and LVEF, respectively has been studied in only a small number of patients with a marked decrease in RVEF and LVEF. The aim of the present study was to compare LVEF and RVEF in patients with ischemic heart disease. RVEF and LVEF were measured by Cardiovascular Magnetic Resonance (CMR imaging. Materials and Methods: This observational study was done in Ghaem general hospital in 2014.  LVEF and RVEF were measured in a series of 33 patients with ischemic heart disease, undergoing CMR for the evaluation of myocardial viability. The correlation between RVEF and LVEF in patients with ischemic heart disease was studied, using Pearson product-moment correlation coefficient analysis.   This study was done in Ghaem general hospital in 2014 with simple sapling. Results: Right ventricular end diastolic volume (186.33±58.90 and left ventricular end diastolic volume (121.72±61.64 were significantly correlated (r=0.223, P=0.005. Moreover, there was a significant correlation between right ventricular end systolic volume (88.18±40.90 and left ventricular end systolic volume (140.96±35.33 (r=0.329, P=0.000. The most significant association was observed between RVEF and LVEF (r=0.913, P=0.000. Conclusion: Based on the findings, RVEF and LVEF were significantly correlated in patients with ischemic heart disease, although this association was not always present in all cardiac patients. The cause of this discrepancy is still unknown.

  5. Disappearance of myocardial perfusion defects on prone SPECT imaging: Comparison with cardiac magnetic resonance imaging in patients without established coronary artery disease

    Directory of Open Access Journals (Sweden)

    Hedén Bo

    2009-08-01

    Full Text Available Abstract Background It is of great clinical importance to exclude myocardial infarction in patients with suspected coronary artery disease who do not have stress-induced ischemia. The diagnostic use of myocardial perfusion single-photon emission computed tomography (SPECT in this situation is sometimes complicated by attenuation artifacts that mimic myocardial infarction. Imaging in the prone position has been suggested as a method to overcome this problem. Methods In this study, 52 patients without known prior infarction and no stress-induced ischemia on SPECT imaging were examined in both supine and prone position. The results were compared with cardiac magnetic resonance imaging (CMR with delayed-enhancement technique to confirm or exclude myocardial infarction. Results There were 63 defects in supine-position images, 37 of which disappeared in the prone position. None of the 37 defects were associated with myocardial infarction by CMR, indicating that all of them represented attenuation artifacts. Of the remaining 26 defects that did not disappear on prone imaging, myocardial infarction was confirmed by CMR in 2; the remaining 24 had no sign of ischemic infarction but 2 had other kinds of myocardial injuries. In 3 patients, SPECT failed to detect small scars identified by CMR. Conclusion Perfusion defects in the supine position that disappeared in the prone position were caused by attenuation, not myocardial infarction. Hence, imaging in the prone position can help to rule out ischemic heart disease for some patients admitted for SPECT with suspected but not documented ischemic heart disease. This would indicate a better prognosis and prevent unnecessary further investigations and treatment.

  6. Electro-mechanical characteristics of myocardial infarction border zones and ventricular arrhythmic risk: novel insights from grid-tagged cardiac magnetic resonance imaging

    International Nuclear Information System (INIS)

    To investigate whether grid-tag myocardial strain evaluation can characterise 'border-zone' peri-infarct region and identify patients at risk of ventricular arrhythmia as the peri-infarct myocardial zone may represent an important contributor to ventricular arrhythmia following ST-segment elevation myocardial infarction (STEMI). Forty-five patients with STEMI underwent cardiac magnetic resonance (CMR) imaging on days 3 and 90 following primary percutaneous coronary intervention (PCI). Circumferential peak circumferential systolic strain (CS) and strain rate (CSR) were calculated from grid-tagged images. Myocardial segments were classified into 'infarct', 'border-zone', 'adjacent' and 'remote' regions by late-gadolinium enhancement distribution. The relationship between CS and CSR and these distinct myocardial regions was assessed. Ambulatory Holter monitoring was performed 14 days post myocardial infarction (MI) to estimate ventricular arrhythmia risk via evaluation of heart-rate variability (HRV). We analysed 1,222 myocardial segments. Remote and adjacent regions had near-normal parameters of CS and CSR. Border-zone regions had intermediate CS (-9.0 ± 4.6 vs -5.9 ± 7.4, P < 0.001) and CSR (-86.4 ± 33.3 vs -73.5 ± 51.4, P < 0.001) severity compared with infarct regions. Patients with 'border-zone' peri-infarct regions had reduced very-low-frequency power on HRV analysis, which is a surrogate for ventricular arrhythmia risk (P = 0.03). Grid-tagged CMR-derived myocardial strain accurately characterises the mechanical characteristics of 'border-zone' peri-infarct region. Presence of 'border-zone' peri-infarct region correlated with a surrogate marker of heightened arrhythmia risk following STEMI. (orig.)

  7. Assessment of left ventricular ejection fraction: comparison of two dimensional echocardiography, cardiac magnetic resonance imaging and 64-row multi-detector computed tomography

    Institute of Scientific and Technical Information of China (English)

    Chee Khoon LIEW; Kui Hian SIM; Rapaee ANNUAR; Tiong Kiam ONG; Sze Piaw CHIN; Tobias Seyfarth; Yean Yip FONG; Wei Ling CHAN; Choon Kiat ANG; Houng Bang LIEW

    2006-01-01

    Objectives To compare left ventricular ejection fraction (LVEF) determined from 64-row multi-detector computed tomography (64-row MDCT) with those determined from two dimensional echocardiography (2D echo) and cardiac magnetic resonance imaging (CMR). Methods Thirty-two patients with coronary artery disease underwent trans-thoracic 2D echo, CMR and contrast-enhanced 64-row MDCT for assessment of LVEF within 48 hours of each other. 64-row MDCT LVEF was derived using the Syngo Circulation software; CMR LVEF was by Area Length Ejection Fraction (ALEF) and Simpson method and 2D echo LVEF by Simpson method.Results The LVEF was 49.13 ± 15.91% by 2D echo, 50.72 ± 16.55% (ALEF method) and 47.65 ± 16.58%(Simpson method) by CMR and 50.00 ± 15.93% by 64-row MDCT. LVEF measurements by 64-row MDCT correlated well with LVEF measured with CMR using either the ALEF method (Pearson correlation r = 0.94, P <0.01) or Simpson method (r = 0.92, P<0.01). It also correlated well with LVEF measured using 2D echo (r = 0.80, P < 0.01). Conclusion LVEF measurements by 64-row MDCT correlated well with LVEF measured by CMR and 2D echo. The correlation between 64-row MDCT and CMR was better than the correlation between 2D echo with CMR. Standard data set from a 64-row MDCT coronary study can be reliably used to calculate the LVEF.

  8. Electro-mechanical characteristics of myocardial infarction border zones and ventricular arrhythmic risk: novel insights from grid-tagged cardiac magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Wong, Dennis T.L.; Weightman, Michael J.; Baumert, Mathias; Tayeb, Hussam; Richardson, James D.; Puri, Rishi; Bertaso, Angela G.; Roberts-Thomson, Kurt C.; Sanders, Prashanthan; Worthley, Matthew I. [University of Adelaide, Cardiovascular Research Centre, Royal Adelaide Hospital and Discipline of Medicine, SA (Australia); Worthley, Stephen G. [University of Adelaide, Cardiovascular Research Centre, Royal Adelaide Hospital and Discipline of Medicine, SA (Australia); Royal Adelaide Hospital, Cardiovascular Investigational Unit, SA (Australia)

    2012-08-15

    To investigate whether grid-tag myocardial strain evaluation can characterise 'border-zone' peri-infarct region and identify patients at risk of ventricular arrhythmia as the peri-infarct myocardial zone may represent an important contributor to ventricular arrhythmia following ST-segment elevation myocardial infarction (STEMI). Forty-five patients with STEMI underwent cardiac magnetic resonance (CMR) imaging on days 3 and 90 following primary percutaneous coronary intervention (PCI). Circumferential peak circumferential systolic strain (CS) and strain rate (CSR) were calculated from grid-tagged images. Myocardial segments were classified into 'infarct', 'border-zone', 'adjacent' and 'remote' regions by late-gadolinium enhancement distribution. The relationship between CS and CSR and these distinct myocardial regions was assessed. Ambulatory Holter monitoring was performed 14 days post myocardial infarction (MI) to estimate ventricular arrhythmia risk via evaluation of heart-rate variability (HRV). We analysed 1,222 myocardial segments. Remote and adjacent regions had near-normal parameters of CS and CSR. Border-zone regions had intermediate CS (-9.0 {+-} 4.6 vs -5.9 {+-} 7.4, P < 0.001) and CSR (-86.4 {+-} 33.3 vs -73.5 {+-} 51.4, P < 0.001) severity compared with infarct regions. Patients with 'border-zone' peri-infarct regions had reduced very-low-frequency power on HRV analysis, which is a surrogate for ventricular arrhythmia risk (P = 0.03). Grid-tagged CMR-derived myocardial strain accurately characterises the mechanical characteristics of 'border-zone' peri-infarct region. Presence of 'border-zone' peri-infarct region correlated with a surrogate marker of heightened arrhythmia risk following STEMI. (orig.)

  9. Quantification of myocardial perfusion using cardiac magnetic resonance imaging correlates significantly to rubidium-82 positron emission tomography in patients with severe coronary artery disease: A preliminary study

    International Nuclear Information System (INIS)

    Introduction: Aim was to compare absolute myocardial perfusion using cardiac magnetic resonance imaging (CMRI) based on Tikhonov's procedure of deconvolution and rubidium-82 positron emission tomography (Rb-82 PET). Materials and methods: Fourteen patients with coronary artery stenosis underwent rest and adenosine stress imaging by 1.5-Tesla MR Scanner and a mCT/PET 64-slice Scanner. CMRI were analyzed based on Tikhonov's procedure of deconvolution without specifying an explicit compartment model using our own software. PET images were analyzed using standard clinical software. CMRI and PET data was compared with Spearman's rho and Bland–Altman analysis. Results: CMRI results were strongly and significantly correlated with PET results for the absolute global myocardial perfusion differences (r = 0.805, p = 0.001) and for global myocardial perfusion reserve (MPR) (r = 0.886, p < 0.001). At vessel territorial level, CMRI results were also significantly correlated with absolute PET myocardial perfusion differences (r = 0.737, p < 0.001) and MPR (r = 0.818, p < 0.001). Each vessel territory had similar strong correlation for absolute myocardial perfusion differences (right coronary artery (RCA): r = 0.787, p = 0.001; left anterior descending artery (LAD): r = 0.796, p = 0.001; left circumflex artery (LCX): r = 0.880, p < 0.001) and for MPR (RCA: r = 0.895, p < 0.001; LAD: r = 0.886, p < 0.001; LCX: r = 0.886, p < 0.001). Conclusion: On a global and vessel territorial basis, CMRI-measured absolute myocardial perfusion differences and MPR were strongly and significantly correlated with the Rb-82 PET findings

  10. Left Ventricular Stroke Volume Quantification by Contrast Echocardiography – Comparison of Linear and Flow-Based Methods to Cardiac Magnetic Resonance

    Science.gov (United States)

    Dele-Michael, Abiola O.; Fujikura, Kana; Devereux, Richard B; Islam, Fahmida; Hriljac, Ingrid; Wilson, Sean R.; Lin, Fay; Weinsaft, Jonathan W.

    2014-01-01

    Background Echocardiography (echo) quantified LV stroke volume (SV) is widely used to assess systolic performance after acute myocardial infarction (AMI). This study compared two common echo approaches – predicated on flow (Doppler) and linear chamber dimensions (Teichholz) – to volumetric SV and global infarct parameters quantified by cardiac magnetic resonance (CMR). Methods Multimodality imaging was performed as part of a post-AMI registry. For echo, SV was measured by Doppler and Teichholz methods. Cine-CMR was used for volumetric SV and LVEF quantification, and delayed-enhancement CMR for infarct size. Results 142 patients underwent same-day echo and CMR. On echo, mean SV by Teichholz (78±17ml) was slightly higher than Doppler (75±16ml; Δ=3±13ml, p=0.02). Compared to SV on CMR (78±18ml), mean difference by Teichholz (Δ=−0.2±14; p=0.89) was slightly smaller than Doppler (Δ−3±14; p=0.02) but limits of agreement were similar between CMR and echo methods (Teichholz: −28, 27 ml, Doppler: −31, 24ml). For Teichholz, differences with CMR SV were greatest among patients with anteroseptal or lateral wall hypokinesis (p<0.05). For Doppler, differences were associated with aortic valve abnormalities or root dilation (p=0.01). SV by both echo methods decreased stepwise in relation to global LV injury as assessed by CMR-quantified LVEF and infarct size (p<0.01). Conclusions Teichholz and Doppler calculated SV yield similar magnitude of agreement with CMR. Teichholz differences with CMR increase with septal or lateral wall contractile dysfunction, whereas Doppler yields increased offsets in patients with aortic remodeling. PMID:23488864

  11. Myocardial motion estimation of tagged cardiac magnetic resonance images using tag motion constraints and multi-level b-splines interpolation.

    Science.gov (United States)

    Liu, Hong; Yan, Meng; Song, Enmin; Wang, Jie; Wang, Qian; Jin, Renchao; Jin, Lianghai; Hung, Chih-Cheng

    2016-05-01

    Myocardial motion estimation of tagged cardiac magnetic resonance (TCMR) images is of great significance in clinical diagnosis and the treatment of heart disease. Currently, the harmonic phase analysis method (HARP) and the local sine-wave modeling method (SinMod) have been proven as two state-of-the-art motion estimation methods for TCMR images, since they can directly obtain the inter-frame motion displacement vector field (MDVF) with high accuracy and fast speed. By comparison, SinMod has better performance over HARP in terms of displacement detection, noise and artifacts reduction. However, the SinMod method has some drawbacks: 1) it is unable to estimate local displacements larger than half of the tag spacing; 2) it has observable errors in tracking of tag motion; and 3) the estimated MDVF usually has large local errors. To overcome these problems, we present a novel motion estimation method in this study. The proposed method tracks the motion of tags and then estimates the dense MDVF by using the interpolation. In this new method, a parameter estimation procedure for global motion is applied to match tag intersections between different frames, ensuring specific kinds of large displacements being correctly estimated. In addition, a strategy of tag motion constraints is applied to eliminate most of errors produced by inter-frame tracking of tags and the multi-level b-splines approximation algorithm is utilized, so as to enhance the local continuity and accuracy of the final MDVF. In the estimation of the motion displacement, our proposed method can obtain a more accurate MDVF compared with the SinMod method and our method can overcome the drawbacks of the SinMod method. However, the motion estimation accuracy of our method depends on the accuracy of tag lines detection and our method has a higher time complexity. PMID:26712656

  12. 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…

  13. Magnetic resonance imaging tracing of transplanted bone marrow mesenchymal stem cells in a rat model of cardiac arrest-induced global brain ischemia

    Institute of Scientific and Technical Information of China (English)

    Yue Fu; Xiangshao Fang; Tong Wang; Jiwen Wang; Jun Jiang; Zhigang Luo; Xiaohui Duan; Jun Shen; Zitong Huang

    2009-01-01

    BACKGROUND: Numerous studies have shown that magnetic resonance imaging (MRI) can detect survival and migration of super paramagnetic iron oxide-labeled stem cells in models of focal cerebral infarction. OBJECTIVE: To observe distribution of bone marrow mesenchymal stem cells (BMSCs) in a rat model of global brain ischemia following cardiac arrest and resuscitation, and to investigate the feasibility of tracing iron oxide-labeled BMSCs using non-invasive MRI. DESIGN, TIME AND SETTING: The randomized, controlled, molecular imaging study was performed at the Linbaixin Medical Research Center, Second Affiliated Hospital, Sun Yat-sen University, and the Institute of Cardiopulmonary Cerebral Resuscitation, Sun Yat-sen University, China from October 2006 to February 2009.MATERIALS: A total of 40 clean, Sprague Dawley rats, aged 6 weeks and of either gender, were supplied by the Experimental Animal Center, Sun Yat-sen University, China, for isolation of BMSCs. Feridex (iron oxide), Gyroscan Inetra 1.5T MRI system, and cardiopulmonary resuscitation device were used in this study. METHODS: A total of 30 healthy, male Sprague Dawley rats, aged 6 months, were used to induce ventricular fibrillation using alternating current. After 8 minutes, the rats underwent 6-minute chest compression and mechanical ventilation, followed by electric defibrillation, to establish rat models of global brain ischemia due to cardiac arrest and resuscitation. A total of 24 successful models were randomly assigned to Feridex-labeled and non-labeled groups (n=12 for each group). At 2 hours after resuscitation, 5 x 10 6 Feddex-labeled BMSCs, with protamine sulfate as a carrier, and 5 × 10 6 non-labeled BMSCs were respectively transplanted into both groups of rats through the right carotid artery (cells were harvested in 1 mL phosphate buffered saline). MAIN OUTCOME MEASURES: Feridex-labeled BMSCs were observed by Prussian blue staining and electron microscopy. Signal intensity, celluar viability

  14. Resonant magnetic vortices

    International Nuclear Information System (INIS)

    By using the complex angular momentum method, we provide a semiclassical analysis of electron scattering by a magnetic vortex of Aharonov-Bohm type. Regge poles of the S matrix are associated with surface waves orbiting around the vortex and supported by a magnetic field discontinuity. Rapid variations of sharp characteristic shapes can be observed on scattering cross sections. They correspond to quasibound states which are Breit-Wigner-type resonances associated with surface waves and which can be considered as quantum analogues of acoustic whispering-gallery modes. Such a resonant magnetic vortex could provide a different kind of artificial atom while the semiclassical approach developed here could be profitably extended in various areas of the physics of vortices

  15. 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 does ... What is MRI and how does it work? Magnetic resonance imaging, or MRI, is a way of obtaining very ...

  16. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... during MRI, but this is rarely a problem. Tooth fillings and braces usually are not affected by ... Magnetic Resonance Imaging (MRI) Safety Alzheimer's Disease Head Injury Brain Tumors Images related to Magnetic Resonance Imaging ( ...

  17. 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) ... conditions such as: brain tumors stroke infections developmental anomalies hydrocephalus — dilatation of fluid spaces within the brain ( ...

  18. 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

  19. 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 ...

  20. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

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

  1. 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 ... limitations of MRI of the Head? What is MRI of the Head? Magnetic resonance imaging (MRI) is ...

  2. Parallel Magnetic Resonance Imaging

    CERN Document Server

    Uecker, Martin

    2015-01-01

    The main disadvantage of Magnetic Resonance Imaging (MRI) are its long scan times and, in consequence, its sensitivity to motion. Exploiting the complementary information from multiple receive coils, parallel imaging is able to recover images from under-sampled k-space data and to accelerate the measurement. Because parallel magnetic resonance imaging can be used to accelerate basically any imaging sequence it has many important applications. Parallel imaging brought a fundamental shift in image reconstruction: Image reconstruction changed from a simple direct Fourier transform to the solution of an ill-conditioned inverse problem. This work gives an overview of image reconstruction from the perspective of inverse problems. After introducing basic concepts such as regularization, discretization, and iterative reconstruction, advanced topics are discussed including algorithms for auto-calibration, the connection to approximation theory, and the combination with compressed sensing.

  3. Cardiac magnetic resonance angiography using blood-pool contrast agents. Comparison of citrate-coated very small superparamagnetic iron oxide particles with gadofosveset trisodium in pigs

    International Nuclear Information System (INIS)

    Purpose: To compare citrate-coated very small superparamagnetic iron oxide particles (VSOP) with gadofosveset trisodium as blood pool contrast agents for cardiac magnetic resonance angiography (CMRA) in pigs. Materials and Methods: Animal experiments were approved by the responsible authority. 10 CMRA-like examinations were performed at 1.5 T after administration of VSOP (0.06 mmol Fe/kg; 5 examinations) and gadofosveset trisodium (0.03 mmol Gd/kg; 5 examinations). The CMRA protocol included ECG-gated inversion-recovery-prepared T1-weighted gradient echo imaging (IR-GRE; one slice) and ECG-gated inversion recovery prepared steady state free precession imaging (IR SSFP; one slice) before and 1, 3, 5, 10, 15, 20, 25, 30, 40, 50, and 60 min after injection. At each time point, three different inversion times (TI; 200 msec, 300 msec, and 400 msec) were applied. Contrast-to-noise ratios (CNR) between blood and myocardium were calculated and compared using mixed linear models. Results: No significant differences of CNR were found between IR-GRE and IR SSFP. At 3 and 5 min after contrast agent administration, VSOP showed a significantly higher CNR than gadofosveset trisodium when TI of 200 msec and 300 msec were applied (TI of 200 msec at 3 min: 8.2 ± 0.7 vs. 5.4 ± 0.7; TI of 200 msec at 5 min: 7.9 ± 0.7 vs. 3.5 ± 0.8; TI of 300 msec at 3 min: 11.7 ± 0.7 vs. 8.8 ± 0.8; TI of 300 msec at 5 min: 11.4 ± 0.7 vs. 8.0 ± 0.8; p < 0.05). Moreover, significant differences in favor of VSOP were found for all time points from 10 to 40 min irrespective of TI (p < 0.05). Conclusion: VSOP has superior blood-pool properties compared to gadofosveset trisodium resulting in prolonged improvement of CNR on CMRA. (orig.)

  4. Cardiac magnetic resonance angiography using blood-pool contrast agents. Comparison of citrate-coated very small superparamagnetic iron oxide particles with gadofosveset trisodium in pigs

    Energy Technology Data Exchange (ETDEWEB)

    Schnorr, J.; Taupitz, M.; Schellenberger, E.A.; Warmuth, C.; Wagner, S.; Kaufels, N.; Wagner, M. [Charite - Universitaetsmedizin Berlin (Germany). Inst. fuer Radiologie; Fahlenkamp, U.L. [Charite - Universitaetsmedizin Berlin (Germany). Inst. fuer Radiologie; Universitaetsklinikum Bonn (Germany). Radiologische Klinik

    2012-02-15

    Purpose: To compare citrate-coated very small superparamagnetic iron oxide particles (VSOP) with gadofosveset trisodium as blood pool contrast agents for cardiac magnetic resonance angiography (CMRA) in pigs. Materials and Methods: Animal experiments were approved by the responsible authority. 10 CMRA-like examinations were performed at 1.5 T after administration of VSOP (0.06 mmol Fe/kg; 5 examinations) and gadofosveset trisodium (0.03 mmol Gd/kg; 5 examinations). The CMRA protocol included ECG-gated inversion-recovery-prepared T1-weighted gradient echo imaging (IR-GRE; one slice) and ECG-gated inversion recovery prepared steady state free precession imaging (IR SSFP; one slice) before and 1, 3, 5, 10, 15, 20, 25, 30, 40, 50, and 60 min after injection. At each time point, three different inversion times (TI; 200 msec, 300 msec, and 400 msec) were applied. Contrast-to-noise ratios (CNR) between blood and myocardium were calculated and compared using mixed linear models. Results: No significant differences of CNR were found between IR-GRE and IR SSFP. At 3 and 5 min after contrast agent administration, VSOP showed a significantly higher CNR than gadofosveset trisodium when TI of 200 msec and 300 msec were applied (TI of 200 msec at 3 min: 8.2 {+-} 0.7 vs. 5.4 {+-} 0.7; TI of 200 msec at 5 min: 7.9 {+-} 0.7 vs. 3.5 {+-} 0.8; TI of 300 msec at 3 min: 11.7 {+-} 0.7 vs. 8.8 {+-} 0.8; TI of 300 msec at 5 min: 11.4 {+-} 0.7 vs. 8.0 {+-} 0.8; p < 0.05). Moreover, significant differences in favor of VSOP were found for all time points from 10 to 40 min irrespective of TI (p < 0.05). Conclusion: VSOP has superior blood-pool properties compared to gadofosveset trisodium resulting in prolonged improvement of CNR on CMRA. (orig.)

  5. Microvascular obstruction on delayed enhancement cardiac magnetic resonance imaging after acute myocardial infarction, compared with myocardial {sup 201}Tl and {sup 123}I-BMIPP dual SPECT findings

    Energy Technology Data Exchange (ETDEWEB)

    Mori, Hiroaki [Department of Cardiology, Nagoya University Graduate School of Medicine, Nagoya (Japan); Department of Cardiology, Kainan Hospital, Yatomi (Japan); Isobe, Satoshi, E-mail: sisobe@med.nagoya-u.ac.jp [Department of Cardiology, Nagoya University Graduate School of Medicine, Nagoya (Japan); Sakai, Shinichi [Department of Cardiology, Kainan Hospital, Yatomi (Japan); Yamada, Takashi [Department of Cardiology, Nagoya University Graduate School of Medicine, Nagoya (Japan); Watanabe, Naoki; Miura, Manabu [Department of Cardiology, Kainan Hospital, Yatomi (Japan); Uchida, Yasuhiro; Kanashiro, Masaaki; Ichimiya, Satoshi [Department of Cardiology, Yokkaichi Municipal Hospital, Yokkaichi (Japan); Okumura, Takahiro; Murohara, Toyoaki [Department of Cardiology, Nagoya University Graduate School of Medicine, Nagoya (Japan)

    2015-08-15

    Highlights: • The percentage infarct size (%IS) was significantly greater in the microvascular obstruction (MO) group than in the non-MO group. • The percentage mismatch score (%MMS) on dual scintigraphy significantly correlated with the %IS and the percentage MO. • The %MMS was significantly greater in the non-MO group than in the MO group, and was an independent predictor for MO. - Abstract: Background: The hypo-enhanced regions within the hyper-enhanced infarct areas detected by cardiac magnetic resonance (CMR) imaging reflect microvascular obstruction (MO) after acute myocardial infarction (AMI). The combined myocardial thallium-201 ({sup 201}Tl)/iodine-123-15-(p-iodophenyl)-3-(R,S)-methylpentadecanoic acid ({sup 123}I-BMIPP) dual single-photon emission computed tomography (SPECT) is a useful tool for detecting myocardial reversibility after AMI. We evaluated whether MO could be an early predictor of irreversible myocardial damage in comparison with {sup 201}Tl and {sup 123}I-BMIPP dual SPECT findings in AMI patients. Methods: Sixty-two patients with initial AMI who successfully underwent coronary revascularization were enrolled. MO was defined by CMR imaging. Patients were divided into 2 groups as follows: MO group (n = 32) and non-MO group (n = 30). Scintigraphic defect scores were calculated using a 17-segment model with a 5-point scoring system. The mismatch score (MMS) was calculated as follows: the total sum of (Σ) {sup 123}I-BMIPP defect score minus Σ{sup 201}Tl defect score. The percentage mismatch score (%MMS) was calculated as follows: MMS/(Σ{sup 123}I-BMIPP score) × 100 (%). Results: The percentage infarct size (%IS) was significantly greater in the MO group than in the non-MO group (32.2 ± 13.8% vs. 18.3 ± 12.1%, p < 0.001). The %MMS significantly correlated with the %IS and the percentage MO (r = −0.26, p = 0.03; r = −0.45, p < 0.001, respectively). The %MMS was significantly greater in the non-MO group than in the MO group (45.4

  6. Determinants of discrepancies in detection and comparison of the prognostic significance of left ventricular hypertrophy by electrocardiogram and cardiac magnetic resonance imaging.

    Science.gov (United States)

    Bacharova, Ljuba; Chen, Haiying; Estes, E Harvey; Mateasik, Anton; Bluemke, David A; Lima, Joao A C; Burke, Gregory L; Soliman, Elsayed Z

    2015-02-15

    Despite the low sensitivity of the electrocardiogram (ECG) in detecting left ventricular hypertrophy (LVH), ECG-LVH is known to be a strong predictor of cardiovascular risk. Understanding reasons for the discrepancies in detection of LVH by ECG versus imaging could help improve the diagnostic ability of ECG. We examined factors associated with false-positive and false-negative ECG-LVH, using cardiac magnetic resonance imaging (MRI) as the gold standard. We also compared the prognostic significance of ECG-LVH and MRI-LVH as predictors of cardiovascular events. This analysis included 4,748 participants (mean age 61.9 years, 53.5% females, 61.7% nonwhites). Logistic regression with stepwise selection was used to identify factors associated with false-positive (n = 208) and false-negative (n = 387), compared with true-positive (n = 208) and true-negative (n = 4,041) ECG-LVH, respectively. A false-negative ECG-LVH status was associated with increased odds of Hispanic race/ethnicity, current smoking, hypertension, increased systolic blood pressure, prolongation of QRS duration, and higher body mass index and with lower odds of increased ejection fraction (model-generalized R(2) = 0.20). A false-positive ECG-LVH status was associated with lower odds of black race, Hispanic race/ethnicity, minor ST-T abnormalities, increased systolic blood pressure, and presence of any major electrocardiographic abnormalities (model-generalized R(2) = 0.29). Both ECG-LVH and MRI-LVH were associated with an increased risk of cardiovascular disease events (hazard ratio 1.51, 95% confidence interval 1.03 to 2.20 and hazard ratio 1.81, 95% confidence interval 1.33 to 2.46, respectively). In conclusion, discrepancy in LVH detection by ECG and MRI can be relatively improved by considering certain participant characteristics. Discrepancy in diagnostic performance, yet agreement on predictive ability, suggests that LVH by ECG and LVH by imaging are likely to be two distinct but somehow related

  7. Myocardial area at risk after ST-elevation myocardial infarction measured with the late gadolinium enhancement after scar remodeling and T2-weighted cardiac magnetic resonance imaging

    DEFF Research Database (Denmark)

    Lønborg, Jacob; Engstrøm, Thomas; Mathiasen, Anders B;

    2012-01-01

    To evaluate the myocardial area at risk (AAR) measured by the endocardial surface area (ESA) method on late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) when applied after scar remodeling (3 months after index infarction) compared to T2-weighted CMR imaging. One hundred and...

  8. Myocardial area at risk after ST-elevation myocardial infarction measured with the late gadolinium enhancement after scar remodeling and T2-weighted cardiac magnetic resonance imaging

    DEFF Research Database (Denmark)

    Lønborg, Jacob; Engstrøm, Thomas; Mathiasen, Anders B;

    2011-01-01

    To evaluate the myocardial area at risk (AAR) measured by the endocardial surface area (ESA) method on late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) when applied after scar remodeling (3 months after index infarction) compared to T2-weighted CMR imaging. One hundred and...

  9. Cavity- and waveguide-resonators in electron paramagnetic resonance, nuclear magnetic resonance, and magnetic resonance imaging.

    Science.gov (United States)

    Webb, Andrew

    2014-11-01

    Cavity resonators are widely used in electron paramagnetic resonance, very high field magnetic resonance microimaging and also in high field human imaging. The basic principles and designs of different forms of cavity resonators including rectangular, cylindrical, re-entrant, cavity magnetrons, toroidal cavities and dielectric resonators are reviewed. Applications in EPR and MRI are summarized, and finally the topic of traveling wave MRI using the magnet bore as a waveguide is discussed. PMID:25456314

  10. Cardiovascular magnetic resonance imaging - a pictorial review

    OpenAIRE

    Vijay Dahya; Spottiswoode, Bruce S.

    2010-01-01

    Cardiovascular magnetic resonance imaging (CMR) is a powerful problem-solving tool and arguably offers the most comprehensive assessment of cardiac morphology and function, as well as the opportunity of rebuilding the bridge between cardiologists and radiologists. The role of CMR-trained imaging physicists is also valuable, and many CMR centres harmoniously incorporate these three sub-specialty fields. This paper comprises an overview of several CMR techniques, outlining both the strengths...

  11. Cardiovascular magnetic resonance imaging - a pictorial review

    Directory of Open Access Journals (Sweden)

    Vijay Dahya

    2010-12-01

    Full Text Available Cardiovascular magnetic resonance imaging (CMR is a powerful problem-solving tool and arguably offers the most comprehensive assessment of cardiac morphology and function, as well as the opportunity of rebuilding the bridge between cardiologists and radiologists. The role of CMR-trained imaging physicists is also valuable, and many CMR centres harmoniously incorporate these three sub-specialty fields. This paper comprises an overview of several CMR techniques, outlining both the strengths and limitations of the modality.

  12. Magnetic Resonance Facility (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2012-03-01

    This fact sheet provides information about Magnetic Resonance Facility capabilities and applications at NREL's National Bioenergy Center. Liquid and solid-state analysis capability for a variety of biomass, photovoltaic, and materials characterization applications across NREL. NREL scientists analyze solid and liquid samples on three nuclear magnetic resonance (NMR) spectrometers as well as an electron paramagnetic resonance (EPR) spectrometer.

  13. 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 Head and Neck Cancer Treatment Brain Tumor Treatment Magnetic Resonance Imaging (MRI) Safety Alzheimer's Disease Head Injury Brain Tumors Images related to Magnetic ...

  14. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... Resources Professions Site Index A-Z Magnetic Resonance Imaging (MRI) - Head Magnetic resonance imaging (MRI) of the head uses a powerful magnetic ... that are clearer and more detailed than other imaging methods. This exam does not use ionizing radiation ...

  15. Artifacts in Magnetic Resonance Imaging

    International Nuclear Information System (INIS)

    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

  16. Cranial magnetic resonance imaging

    International Nuclear Information System (INIS)

    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

  17. Dental magnetic resonance imaging

    International Nuclear Information System (INIS)

    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.

  18. Magnetic resonance imaging equipments

    International Nuclear Information System (INIS)

    Magnetic resonance imaging (MRI) is a new examination technique used in diagnostic medicine. Its use has increased notably during the last few years in Finland, too. The biological effects of electromagnetic fields used in MRI are quite different from the effects of x-rays. This report introduces the physics and the techniques of MRI; the biological effects of magnetic fields and the hazards associated with the use of MRI systems are briefly discussed. The major national and international recommendations are summarized, too. Furthermore, a description is given how safety aspects are considered in Finnish MRI units. Finally, recommendations are given to restrict the exposure caused by MRI and to ensure the safe use of MRI. Diagnostic applications and clinical or economic aspects fall outside the scope of this report. (orig.)

  19. 心脏磁共振成像技术在扩张型心肌病中的应用及研究进展%Application and Research Progress of Cardiac Magnetic Resonance Imaging in Dilated Cardiomyopathy

    Institute of Scientific and Technical Information of China (English)

    张颖雪(综述); 赵新湘; 孙勇(审校)

    2016-01-01

    扩张型心肌病是心肌病中最常见的类型,其病因复杂、病情呈进行性加重,预后较差。如何对其潜在的风险进行预测,对临床具有重要的意义,而心脏磁共振技术已成为一种有效的“一站式”心脏检查手段,可对此提供明确有效的帮助。现就多种心脏磁共振技术在扩张型心肌病中的研究进展做一综述。%Dilated cardiomyopathy is the most common type of cardiomyopathy , the cause of which is complicated , the disease is pro-gressive and the prognosis is poor .How to predict the potential risk has important significance to the clinic .Cardiac magnetic resonance ima-ging technology has become an effective “one-stop” method for the diagnosis of heart disease ,which can provide a clear and effective help . The research progress of multiple cardiac magnetic resonance imaging technology in dilated cardiomyopathy is summarized in this article .

  20. 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.

  1. Effects of High-dose Atorvastatin Pretreatment in Patients with ST-segment Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention: A Cardiac Magnetic Resonance Study

    OpenAIRE

    Kim, Eun Kyoung; Hahn, Joo-Yong; Song, Young Bin; Chang, Sung-A; Choi, Jin-Ho; Choi, Seung-Hyuk; Lee, Sang-Chol; Choe, Yeon Hyeon; Lee, Sang Hoon; Gwon, Hyeon-Cheol

    2015-01-01

    It is uncertain that atorvastatin pretreatment can reduce myocardial damage in patients undergoing primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI). The aim of this study was to investigate the effects of atorvastatin pretreatment on infarct size measured by contrast-enhanced magnetic resonance imaging (CE-MRI) in STEMI patients. Patients undergoing primary PCI for STEMI within 12 hr after symptom onset were randomized to an atorvastatin ...

  2. 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

  3. Gated SPECT evaluation of left ventricular function using a CZT camera and a fast low-dose clinical protocol: comparison to cardiac magnetic resonance imaging

    International Nuclear Information System (INIS)

    CZT technology allows ultrafast low-dose myocardial scintigraphy but its accuracy in assessing left ventricular function is still to be defined. The study group comprised 55 patients (23 women, mean age 63 ± 9 years) referred for myocardial perfusion scintigraphy. The patients were studied at rest using a CZT camera (Discovery NM530c; GE Healthcare) and a low-dose 99mTc-tetrofosmin clinical protocol (mean dose 264 ± 38 MBq). Gated SPECT imaging was performed as a 6-min list-mode acquisition, 15 min after radiotracer injection. Images were reformatted (8-frame to 16-frame) using Lister software on a Xeleris workstation (GE Healthcare) and then reconstructed with a dedicated iterative algorithm. Analysis was performed using Quantitative Gated SPECT (QGS) software. Within 2 weeks patients underwent cardiac magnetic resonance imaging (cMRI, 1.5-T unit CVi; GE Healthcare) using a 30-frame acquisition protocol and dedicated software for analysis (MASS 6.1; Medis). The ventricular volumes obtained with 8-frame QGS showed excellent correlations with the cMRI volumes (end-diastolic volume (EDV), r = 0.90; end-systolic volume (ESV), r = 0.94; p < 0.001). However, QGS significantly underestimated the ventricular volumes (mean differences: EDV, -39.5 ± 29 mL; ESV, -15.4 ± 22 mL; p < 0.001). Similarly, the ventricular volumes obtained with 16-frame QGS showed an excellent correlations with the cMRI volumes (EDV, r = 0.92; ESV, r = 0.95; p < 0.001) but with significant underestimations (mean differences: EDV, -33.2 ± 26 mL; ESV, -17.9 ± 20 mL; p < 0.001). Despite significantly lower values (47.9 ± 16 % vs. 51.2 ± 15 %, p < 0.008), 8-frame QGS mean ejection fraction (EF) was closely correlated with the cMRI values (r = 0.84, p < 0.001). The mean EF with 16-frame QGS showed the best correlation with the cMRI values (r = 0.91, p < 0.001) and was similar to the mean cMRI value (49.6 ± 16 %, p not significant). Regional analysis showed a good correlation between both 8-frame

  4. Gated SPECT evaluation of left ventricular function using a CZT camera and a fast low-dose clinical protocol: comparison to cardiac magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Giorgetti, Assuero; Masci, Pier Giorgio; Marras, Gavino; Gimelli, Alessia; Genovesi, Dario; Lombardi, Massimo [Fondazione CNR/Regione Toscana ' ' G. Monasterio' ' , Pisa (Italy); Rustamova, Yasmine K. [Azerbaijan Medical University, Department of internal medicine Central Customs Hospital, Baku (Azerbaijan); Marzullo, Paolo [Istituto di Fisiologia Clinica del CNR, Pisa (Italy)

    2013-12-15

    CZT technology allows ultrafast low-dose myocardial scintigraphy but its accuracy in assessing left ventricular function is still to be defined. The study group comprised 55 patients (23 women, mean age 63 {+-} 9 years) referred for myocardial perfusion scintigraphy. The patients were studied at rest using a CZT camera (Discovery NM530c; GE Healthcare) and a low-dose {sup 99m}Tc-tetrofosmin clinical protocol (mean dose 264 {+-} 38 MBq). Gated SPECT imaging was performed as a 6-min list-mode acquisition, 15 min after radiotracer injection. Images were reformatted (8-frame to 16-frame) using Lister software on a Xeleris workstation (GE Healthcare) and then reconstructed with a dedicated iterative algorithm. Analysis was performed using Quantitative Gated SPECT (QGS) software. Within 2 weeks patients underwent cardiac magnetic resonance imaging (cMRI, 1.5-T unit CVi; GE Healthcare) using a 30-frame acquisition protocol and dedicated software for analysis (MASS 6.1; Medis). The ventricular volumes obtained with 8-frame QGS showed excellent correlations with the cMRI volumes (end-diastolic volume (EDV), r = 0.90; end-systolic volume (ESV), r = 0.94; p < 0.001). However, QGS significantly underestimated the ventricular volumes (mean differences: EDV, -39.5 {+-} 29 mL; ESV, -15.4 {+-} 22 mL; p < 0.001). Similarly, the ventricular volumes obtained with 16-frame QGS showed an excellent correlations with the cMRI volumes (EDV, r = 0.92; ESV, r = 0.95; p < 0.001) but with significant underestimations (mean differences: EDV, -33.2 {+-} 26 mL; ESV, -17.9 {+-} 20 mL; p < 0.001). Despite significantly lower values (47.9 {+-} 16 % vs. 51.2 {+-} 15 %, p < 0.008), 8-frame QGS mean ejection fraction (EF) was closely correlated with the cMRI values (r = 0.84, p < 0.001). The mean EF with 16-frame QGS showed the best correlation with the cMRI values (r = 0.91, p < 0.001) and was similar to the mean cMRI value (49.6 {+-} 16 %, p not significant). Regional analysis showed a good

  5. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... or cause problems during an MRI exam. Nephrogenic systemic fibrosis is currently a recognized, but rare, complication ... Tumor Treatment Magnetic Resonance Imaging (MRI) Safety Alzheimer's Disease Head Injury Brain Tumors Images related to Magnetic ...

  6. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... the same effect. A very irregular heartbeat may affect the quality of images obtained using techniques that ... Tumor Treatment Magnetic Resonance Imaging (MRI) Safety Alzheimer's Disease Head Injury Brain Tumors Images related to Magnetic ...

  7. Evaluation of left ventricular volumes measured by magnetic resonance imaging

    DEFF Research Database (Denmark)

    Møgelvang, J; Thomsen, C; Mehlsen, J;

    1986-01-01

    Left ventricular end-diastolic and end-systolic volumes were determined in 17 patients with different levels of left ventricular function by magnetic resonance imaging (MRI). A 1.5 Tesla Magnet was used obtaining ECG triggered single and multiple slices. Calculated cardiac outputs were compared...

  8. Magnetic resonance in neuroborreliosis

    International Nuclear Information System (INIS)

    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)

  9. 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 News Physician Resources Professions Site Index A-Z Magnetic Resonance Imaging (MRI) - Head Magnetic resonance imaging (MRI) of the head uses a ...

  10. 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

  11. Magnetic resonance imaging methodology

    International Nuclear Information System (INIS)

    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.)

  12. Magnetic Resonance angiography. Pt 1

    International Nuclear Information System (INIS)

    The objective of this paper is to describe the basic physical principles important in magnetic resonance angiography (MRA). The data used were obtained from recent articles on MRA and direct experience working with prototype MRA sequence. The information is presented in a manner suitable for those unfamiliar with the principles of MRA and magnetic resonance imaging (MRI). Magnetic resonance angiography is an important method that can be used to obtain angiograms without the injection of intravascular contrast medium. It is already proving to be of clinical use in the assessment of vascular disease. 11 refs., 5 figs

  13. 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

  14. 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

  15. Functional magnetic resonance imaging.

    Science.gov (United States)

    Buchbinder, Bradley R

    2016-01-01

    Functional magnetic resonance imaging (fMRI) maps the spatiotemporal distribution of neural activity in the brain under varying cognitive conditions. Since its inception in 1991, blood oxygen level-dependent (BOLD) fMRI has rapidly become a vital methodology in basic and applied neuroscience research. In the clinical realm, it has become an established tool for presurgical functional brain mapping. This chapter has three principal aims. First, we review key physiologic, biophysical, and methodologic principles that underlie BOLD fMRI, regardless of its particular area of application. These principles inform a nuanced interpretation of the BOLD fMRI signal, along with its neurophysiologic significance and pitfalls. Second, we illustrate the clinical application of task-based fMRI to presurgical motor, language, and memory mapping in patients with lesions near eloquent brain areas. Integration of BOLD fMRI and diffusion tensor white-matter tractography provides a road map for presurgical planning and intraoperative navigation that helps to maximize the extent of lesion resection while minimizing the risk of postoperative neurologic deficits. Finally, we highlight several basic principles of resting-state fMRI and its emerging translational clinical applications. Resting-state fMRI represents an important paradigm shift, focusing attention on functional connectivity within intrinsic cognitive networks. PMID:27432660

  16. Magnetic resonance energy and topological resonance energy.

    Science.gov (United States)

    Aihara, Jun-Ichi

    2016-04-28

    Ring-current diamagnetism of a polycyclic π-system is closely associated with thermodynamic stability due to the individual circuits. Magnetic resonance energy (MRE), derived from the ring-current diamagnetic susceptibility, was explored in conjunction with graph-theoretically defined topological resonance energy (TRE). For many aromatic molecules, MRE is highly correlative with TRE with a correlation coefficient of 0.996. For all π-systems studied, MRE has the same sign as TRE. The only trouble with MRE may be that some antiaromatic and non-alternant species exhibit unusually large MRE-to-TRE ratios. This kind of difficulty can in principle be overcome by prior geometry-optimisation or by changing spin multiplicity. Apart from the semi-empirical resonance-theory resonance energy, MRE is considered as the first aromatic stabilisation energy (ASE) defined without referring to any hypothetical polyene reference. PMID:26878709

  17. Magnetic Resonance Imaging: A Wealth of Cardiovascular Information

    OpenAIRE

    Shah, Sangeeta; Chryssos, Emanuel D.; Parker, Hugh

    2009-01-01

    Cardiac magnetic resonance imaging is a relatively new noninvasive imaging modality that provides insight into multiple facets of the human myocardium not available by other imaging modalities. This one test allows for the assessment of ventricular and valvular function, ischemic and nonischemic cardiomyopathies, congenital heart disease, and cardiac tumors. It has been coined by many as “one-stop shopping.” As with any imaging modality, it is important to understand not only the indications ...

  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 News Physician Resources Professions Site Index A-Z Magnetic Resonance Imaging (MRI) - ...

  19. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... Magnetic resonance imaging (MRI) is a noninvasive medical test that physicians use to diagnose and treat medical ... CD. Currently, MRI is the most sensitive imaging test of the head (particularly the brain) in routine ...

  20. 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 and treat ...

  1. 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...

  2. 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.

  3. Magnetic Resonance Connectome Automated Pipeline

    OpenAIRE

    Gray, William R.; Bogovic, John A.; Vogelstein, Joshua T; Landman, Bennett A.; Prince, Jerry L.; Vogelstein, R. Jacob

    2011-01-01

    This manuscript presents a novel, tightly integrated pipeline for estimating a connectome, which is a comprehensive description of the neural circuits in the brain. The pipeline utilizes magnetic resonance imaging (MRI) data to produce a high-level estimate of the structural connectivity in the human brain. The Magnetic Resonance Connectome Automated Pipeline (MRCAP) is efficient and its modular construction allows researchers to modify algorithms to meet their specific requirements. The pipe...

  4. Advances in magnetic resonance 4

    CERN Document Server

    Waugh, John S

    2013-01-01

    Advances in Magnetic Resonance, Volume 4 deals with the relaxation, irradiation, and other dynamical effects that is specific to systems having resolved structure in their magnetic resonance spectra. This book discusses the anisotropic rotation of molecules in liquids by NMR quadrupolar relaxation; rotational diffusion constants; alternating linewidth effect; and theoretical formulations of the problem. The line shapes in high-resolution NMR; matrix representations of the equations of motion; matrix representations of the equations of motion; and intramolecular hydrogen bonds are also delibera

  5. Nuclear magnetic gamma double resonance

    International Nuclear Information System (INIS)

    A number of problems corresponding to different variants of experiments using nuclear magnetic-gamma double resonance (NMGDR) are theoretically investigated. Calculation is carried out and its results are compared to experimental ones concerning NMGDR for tantalum. Time dynamics of the source or scatterer nucleus sublevel populations under double resonance conditions with non-uniform initial population of this nucleus sublevels is studied

  6. Application of Magnetic Resonance Imaging in Diagnosis and Research of Cardiac Diseases%核磁共振成像在心脏病诊断及研究中的应用

    Institute of Scientific and Technical Information of China (English)

    余昕

    2013-01-01

    Magnetic resonance imaging (MRI) is a noninvasive imaging method that does not involve ionizing radiation. Because of its high imaging resolution and high soft tissue contrast, it has increasingly been used in both clinical and basic science research. This review focuses on the applications of MRI in the evaluation of cardiac function. Specifically, two methods will be discussed:the assessment of ventricular anatomy and global cardiac function by cine MRI, and the quantification of regional myocardial wall motion mechanics by MRI tagging.%磁共振成像(MRI)具有无创、无电离辐射、分辨率高、软组织造影清晰等特点,被越来越多地应用于临床和基础研究。本文综述了磁共振成像在心功能评价方面的应用,包括磁共振电影对心脏结构和宏观功能指数的评价,以及它的临床应用,并重点介绍了MRI心肌标记技术,及其在心肌收缩力学分析方面的应用。

  7. Magnetic Resonance Imaging of Thoracic Aortic Dissections

    OpenAIRE

    Sax, Steven L.

    1990-01-01

    Magnetic resonance imaging is an excellent noninvasive method for evaluating thoracic aortic dissections. A variety of magnetic resonance scans of aortic dissections are shown, documenting the ability of magnetic resonance to image the true lumen, the false channel, and the intimal septum. Detail is provided on magnetic resonance imaging techniques and findings. (Texas Heart Institute Journal 1990;17:262-70)

  8. Advances in magnetic resonance 5

    CERN Document Server

    Waugh, John S

    2013-01-01

    Advances in Magnetic Resonance, Volume 5 deals with the interpretation of ESR spectra and provides descriptions of experimental apparatus. This book discusses the halogen hyperfine interactions; organic radicals in single crystals; pulsed-Fourier-transform nuclear magnetic resonance spectrometer; and inhomogenizer and decoupler. The spectrometers for multiple-pulse NMR; weak collision theory of relaxation in the rotating frame; and spin Hamiltonian for the electron spin resonance of irradiated organic single crystals are also deliberated. This text likewise covers the NMR in helium three and m

  9. Practical value of cardiac magnetic resonance imaging in unstable angina diagnosis%心脏核磁共振在不稳定型心绞痛诊治中的应用价值

    Institute of Scientific and Technical Information of China (English)

    唐新宇; 欧阳容

    2012-01-01

    Objective To investigate the value of magnetic resonance imaging of heart in diagnosis of unstable angina pectoris.Methods A total of 24 patients with unstable angina pectoris including 15 male and 9 female confirmed by coronary angiography (CAG) were enrolled.All 24 patients were scanned by cardiac magnetic resonance imaging ( CMR),and then the analyses of the first pass images and the delayed contrast enhancement images were carried out for comparison.The findings of cardiac structure,cardiac function,myocardial ischemia,myocardial necrosis,myocardial edema were taken for answering to the images made by echocardiography (UCG) and coronary angiography (CAG) linked with conventional examinations for the diagnosis of coronary disease.Results Compared with the UCG,CMR provided more detailed information about the right ventricle,and the information about left ventricular structure and function given by UCG was very good consistent with that offered by CMR,and CMR could detect myocardial ischemia,myocardial edema and the myocardial necrosis,which were of good consistency with findings often observed by conventional inspection methods.Conclusions Cardiac magnetic resonance imaging (CMR) is of high value in diagnosis and evaluation of unstable angina pectoris and is far superior over other conventional methods for examinations of unstable angina pectoris.%目的 研究心脏核磁共振在不稳定型心绞痛诊治中的价值.方法 选择确诊不稳定性心绞痛患者24例,其中男性15例,女性9例,均行冠脉造影.对24例患者进行心脏核磁共振(CMR)扫描,对图像进行首过灌注和延迟扫描分析(LEG),记录其在心脏结构、功能、心肌缺血、坏死、水肿等方面的信息,并使之与超声心动图(UCG)、冠脉造影(CAG)等传统检查结果对比.结果 CMR与UCG相比,可以提供更多右心室方面的信息.在左心室结构及功能方面,两者有很好的一致性;CMR能发现并检测心肌缺血、水肿及坏死,

  10. The 20 year evolution of dobutamine stress cardiovascular magnetic resonance

    OpenAIRE

    Hundley W; Charoenpanichkit Charaslak

    2010-01-01

    Abstract Over the past 20 years, investigators world-wide have developed and utilized dobutamine magnetic resonance stress testing procedures for the purpose of identifying ischemia, viability, and cardiac prognosis. This article traces these developments and reviews the data utilized to substantiate this relatively new noninvasive imaging procedure.

  11. Cardiovascular magnetic resonance findings in a case of Danon disease

    OpenAIRE

    Kosieradzka Agnieszka; Walczak Ewa; Kuch Marek; Kownacki Lukasz; Piotrowska-Kownacka Dorota; Fidzianska Anna; Krolicki Leszek

    2009-01-01

    Abstract Danon disease is a rare X-linked dominant lysosomal glycogen storage disease that can lead to severe ventricular hypertrophy and heart failure. We report a case of Danon disease with cardiac involvement evaluated with cardiovascular magnetic resonance, including late gadolinium enhancement and perfusion studies.

  12. Endomyocardial fibrosis and mural thrombus in a 4-year-old girl due to idiopathic hypereosinophilia syndrome described with serial cardiac magnetic resonance imaging.

    Science.gov (United States)

    Tai, Christiana P; Chung, Taylor; Avasarala, Kishor

    2016-01-01

    We present the case of a 4-year-old girl with idiopathic hypereosinophilia syndrome, endomyocardial fibrosis, and mural thrombus. This condition is rarely seen in children outside the tropics. Myocardial biopsy is historically the standard for diagnosis. Reports in adult literature, however, have shown the utility of cardiac MRI as a non-invasive tool for diagnosis, prognosis, and monitoring. To our knowledge, this is the first reported case with serial cardiac MRI in a child. PMID:25683059

  13. Cohort comparison study of cardiac disease and atherosclerotic burden in type 2 diabetic adults using whole body cardiovascular magnetic resonance imaging

    OpenAIRE

    Duce, Suzanne L.; Weir-McCall, Jonathan R.; Gandy, Stephen J.; Matthew, Shona Z.; Cassidy, Deirdre B.; McCormick, Lynne; Rauchhaus, Petra; Looker, Helen; Helen M Colhoun; Houston, J. Graeme

    2015-01-01

    BACKGROUND: Whole body cardiovascular MR (WB CVMR) combines whole body angiography and cardiac MR assessment. It is accepted that there is a high disease burden in patients with diabetes, however the quantification of the whole body atheroma burden in both arterial and cardiac disease has not been previously reported. In this study we compare the quantified atheroma burden in those individuals with and without diabetes by clinical cardiovascular disease (CVD) status.METHODS: 158 participants ...

  14. Cohort comparison study of cardiac disease and atherosclerotic burden in type 2 diabetic adults using whole body cardiovascular magnetic resonance imaging

    OpenAIRE

    Duce, Suzanne L.; Weir-McCall, Jonathan R.; Gandy, Stephen J.; Matthew, Shona Z.; Cassidy, Deirdre B.; McCormick, Lynne; Rauchhaus, Petra; Looker, Helen; Helen M Colhoun; Houston, J. Graeme

    2015-01-01

    Background Whole body cardiovascular MR (WB CVMR) combines whole body angiography and cardiac MR assessment. It is accepted that there is a high disease burden in patients with diabetes, however the quantification of the whole body atheroma burden in both arterial and cardiac disease has not been previously reported. In this study we compare the quantified atheroma burden in those individuals with and without diabetes by clinical cardiovascular disease (CVD) status. Methods 158 participants u...

  15. Regional Microstructural and Volumetric Magnetic Resonance Imaging (MRI) Abnormalities in the Corpus Callosum of Neonates With Congenital Heart Defect Undergoing Cardiac Surgery.

    Science.gov (United States)

    Hagmann, Cornelia; Singer, Jitka; Latal, Beatrice; Knirsch, Walter; Makki, Malek

    2016-03-01

    The purpose of the study is to investigate the structural development of the corpus callosum in term neonates with congenital heart defect before and after surgery using diffusion tensor imaging and 3-dimensional T1-weighted magnetic resonance imaging (MRI). We compared parallel and radial diffusions, apparent diffusion coefficient (ADC), fractional anisotropy, and volume of 5 substructures of the corpus callosum: genu, rostral body, body, isthmus, and splenium. Compared to healthy controls, we found a significantly lower volume of the splenium and total corpus callosum and a higher radial diffusion and lower fractional anisotropy in the splenium of patients presurgery; a lower volume in all substructures in the postsurgery group; higher radial diffusion in the rostral body, body, and splenium; and a higher apparent diffusion coefficient in the splenium of postsurgery patients. Similar fractional anisotropy changes in congenital heart defect patients were reported in preterm infants. Our findings in apparent diffusion coefficient in the splenium of these patients (pre and postsurgery) are comparable to findings in preterm neonates with psychomotor delay. Delayed maturation of the isthmus was also reported in preterm infants. PMID:26129977

  16. The relation between hypointense core, microvascular obstruction and intramyocardial haemorrhage in acute reperfused myocardial infarction assessed by cardiac magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kandler, Diana; Luecke, Christian; Grothoff, Matthias; Andres, Claudia; Lehmkuhl, Lukas; Nitzsche, Stefan; Riese, Franziska; Gutberlet, Matthias [University Leipzig - Heart Centre, Department of Diagnostic and Interventional Radiology, Leipzig (Germany); Mende, Meinhard [University Leipzig, Coordination Centre for Clinical Trials, Leipzig (Germany); Waha, Suzanne de; Desch, Steffen; Lurz, Philipp; Eitel, Ingo [University Leipzig - Heart Centre, Department of Internal Medicine/ Cardiology, Leipzig (Germany)

    2014-12-15

    Intramyocardial haemorrhage (IMH) and microvascular obstruction (MVO) represent reperfusion injury after reperfused ST-elevation myocardial infarction (STEMI) with prognostic impact and ''hypointense core'' (HIC) appearance in T{sub 2}-weighted images. We aimed to distinguish between IMH and MVO by using T{sub 2}{sup *}-weighted cardiovascular magnetic resonance imaging (CMR) and analysed influencing factors for IMH development. A total of 151 patients with acute STEMI underwent CMR after primary angioplasty. T{sub 2}-STIR sequences were used to identify HIC, late gadolinium enhancement to visualise MVO and T{sub 2}{sup *}-weighted sequences to detect IMH. IMH{sup +}/IMH{sup -} patients were compared considering infarct size, myocardial salvage, thrombolysis in myocardial infarction (TIMI) flow, reperfusion time, ventricular volumes, function and pre-interventional medication. Seventy-six patients (50 %) were IMH{sup +}, 82 (54 %) demonstrated HIC and 100 (66 %) MVO. IMH was detectable without HIC in 16 %, without MVO in 5 % and HIC without MVO in 6 %. Multivariable analyses revealed that IMH was associated with significant lower left ventricular ejection fraction and myocardial salvage index, larger left ventricular volume and infarct size. Patients with TIMI flow grade ≤1 before angioplasty demonstrated IMH significantly more often. IMH is associated with impaired left ventricular function and higher infarct size. T{sub 2} and HIC imaging showed moderate agreement for IMH detection. T{sub 2}{sup *} imaging might be the preferred CMR imaging method for comprehensive IMH assessment. (orig.)

  17. Magnetic resonance and porous materials

    International Nuclear Information System (INIS)

    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)

  18. 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.

  19. Magnetic resonance imaging in coronary heart disease

    International Nuclear Information System (INIS)

    Modern level of cardiac magnetic resonance imaging (MRI) development already allows its routine use (with proper indications) in coronary heart disease patients for studies of heart morphology and functions, performance of stress tests for evaluation of myocardial perfusion and contractile function. Coronary MRA and some other new MR techniques are close to its wide-scale clinical application. It has been shown that cardiac MRI is a valuable tool for detection of postinfarction scars, aneurysms, pseudoaneurysms, septal defects, mural thrombi and valvular regurgitations. Due to intrinsic advantages of the method it is of special value when these pathological conditions cannot be fully confirmed or excluded with echocardiography. MRI is recognized as the best imaging method for quantification of myocardial thickness, myocardial mass, systolic myocardial thickening, chamber volumes, ejection fraction and other parameters of global and regional systolic and diastolic function. MRI is used in studies of cardiac remodeling in postinfarction patients. The most attractive areas for cardiovascular applications of MRI are assessment of myocardial perfusion and non-invasive coronary angiography. Substantial progress has been achieved in these directions. There are some other new developments in studies of coronary artery disease with MRI. High-resolution MR is used for imaging and quantification of atherosclerotic plaque composition in vivo. Intravascular MR devices suitable for performing imaging-guided balloon angioplasty are created. But before MRI will be widely accepted by the medical community as a important cardiovascular imaging modality several important problems have to be solved. Further technical advances are necessary for clinical implementation of all major diagnostic capabilities of cardiac MRI. The subjective obstacles for growth of clinical applications of cardiac MRI are lack of understanding of its possibilities and benefits both by clinicians and

  20. Quantification of left ventricular mechanics using vector-velocity imaging, a novel feature tracking algorithm, applied to echocardiography and cardiac magnetic resonance imaging

    Institute of Scientific and Technical Information of China (English)

    LI Peng; MENG Hong; LIU Shi-zhen; Mani A Vannan

    2012-01-01

    Background Tagged magnetic resonance imaging (MRI) is the non-invasive golden standard to measure myocardial deformity.Tissue Doppler Imaging can be used to assess myocardial deformity,however,it has the limitation of angle-dependence.Our study aimed to compare left ventricular torsion and strains measured by velocity-vector imaging (VVI) using echocardiography (echo-VVI) and MRI (MRI-VVI),and to validate them against harmonic phase tagged MRI (HARP MRI).Methods A total number of 34 subjects (14 normal and 20 patients) were evaluated.Apical and basal image of left ventricular short axis view were acquired for measurements of apical and basal rotation.circumferential and radial strain using both echo-VVI and MRI-VVl.An apical four-chamber view was obtained for measuring the distance between the apical and basal levels.Results The correlations of segmental rotations,circumferential and radial strains were high between echo-VVI and HARP MRI,while the agreement of apical rotation was poor.Left ventricular torsion showed much better correlation and agreement between echo-VVI and HARP MRI than apical rotation:the coefficient was 0.97,P <0.001.The correlation between MRI-VVI and HARP MRI in quantifying rotational parameters and strains was similar with echo-VVI and HARP MRI.Echo-VVI could discriminate normal and dysfunctional ventricles on either hypertensive or dilated cardiomyopathy.Conclusion The data from this study show that (1) it is feasible to quantify left ventricular torsion and myocardial strain using echo-VVI and MRI-VVI in normal subjects,patients with left ventricular global systolic dysfunction and segment systolic dysfunction; (2) the agreement among all mechanical parameters derived from echo-VVl,MRI-VVI,and HARP MRI remained with clinically acceptable ranges.

  1. Recommendations concerning magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    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: 31P, 13C, 1H (and possibly 19F and 23Na). 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.)

  2. magnetic resonance imaging,etc.

    Institute of Scientific and Technical Information of China (English)

    张福基

    1998-01-01

    magnetic resonance imaging n.[1984] a noninvasive diagnostic technique that produces computerized images of internal body tissues and is based on nuclear magnetic resonance of atoms within he body induced by the application of radio waves磁共振成像(指一种非侵害 性诊断技术,能生成内部身体组织的计算机化影像,其依据是应用无线电波 感生体内原子并使之产磁共振)

  3. Comparing cardiac magnetic resonance with echocardiogram on diagnosis of apical hypertrophic cardiomyopathy%心尖肥厚型心肌病的MRI与超声心动图对比研究

    Institute of Scientific and Technical Information of China (English)

    袁思殊; 李志伟; 夏黎明

    2015-01-01

    AbrtractObjective:To discuss the character of cardiac magnetic resonance and echocardiogram findings of apical hypertrophic cardiomyopathy (AHCM), and evaluate the diagnostic value of CMR and echocardiogram in AHCM.Materials and Methods: Twenty-one patients (male 16, female 5) with AHCM underwent Cardiac Magnetic Resonance, echocardiogram, ECG and coronary angiography. Results:The cardiac magnetic resonance revealed apical hypertrophic in all the patients. Among them, 13 patients were pure form P-AHCM, 1 patient was pure form T-AHCM, 1 patient was mixed form P-AHCM, and 6 patients were mixed form T-AHCM. Magnetic resonance imaging showed “ace of spades” morphology of the left ventricle in all the T-AHCM patients. Four patients underwent myocardial contrast enhancement MR scanning: 3 patients presented LGE, 2 patients presented myocardial ischemia, and 2 patients presented myocardial infarction. Echocardiography provided correct diagnoses in 6/21 patients (28.6%), while in 10 patients echocardiographic results were normal. All of our patients showed electrocardiographic alterations of the ventricular repolarization: 14 patients (67.7%) with LV high voltage. Seventeen patients (80.9%) with giant negative T waves. Sixteen patients (76.2%) with a signiifcant descending ST segment. Four patients had arrhythmia in different degrees.Conclusions: MR has higher sensitivity in diagnosing AHCM than echocardiogram. The ECG is a helpful tool to screen AHCM. To the patients who is suspected of AHCM, cardiac magnetic resonance could make a deifnite diagnosis.%目的:分析心尖肥厚型心肌病(AHCM)的MRI与超声心动图影像征象,比较MRI与超声心动图对心尖肥厚型心肌病的诊断价值。材料与方法对21例心尖型肥厚型心肌病患者(男16例,女5例)行心脏MRI、超声心动图、心电图等检查。结果21例患者心脏MRI均提示心尖部心肌肥厚,单纯型P-AHCM 13例,单纯型T-AHCM 1例,混合型P-AHCM 1

  4. Cardiovascular magnetic resonance in pericardial diseases

    Directory of Open Access Journals (Sweden)

    Francone Marco

    2009-05-01

    Full Text Available Abstract The pericardium and pericardial diseases in particular have received, in contrast to other topics in the field of cardiology, relatively limited interest. Today, despite improved knowledge of pathophysiology of pericardial diseases and the availability of a wide spectrum of diagnostic tools, the diagnostic challenge remains. Not only the clinical presentation may be atypical, mimicking other cardiac, pulmonary or pleural diseases; in developed countries a shift for instance in the epidemiology of constrictive pericarditis has been noted. Accurate decision making is crucial taking into account the significant morbidity and mortality caused by complicated pericardial diseases, and the potential benefit of therapeutic interventions. Imaging herein has an important role, and cardiovascular magnetic resonance (CMR is definitely one of the most versatile modalities to study the pericardium. It fuses excellent anatomic detail and tissue characterization with accurate evaluation of cardiac function and assessment of the haemodynamic consequences of pericardial constraint on cardiac filling. This review focuses on the current state of knowledge how CMR can be used to study the most common pericardial diseases.

  5. Prenatal magnetic resonance imaging in evaluation of fetal cardiac malposition%胎儿胸腔异常心脏位置的产前磁共振成像诊断

    Institute of Scientific and Technical Information of China (English)

    董素贞; 朱铭; 李奋; 钟玉敏; 张弘; 潘慧红

    2011-01-01

    目的 探讨产前磁共振成像(MRI)在胎儿胸腔异常心脏位置诊断中的应用价值.方法 57例孕妇,孕龄20 ~36周.产前常规行超声检查后24 -48 h内行MRI检查,采用二维快速平衡稳态采集(2D FIESTA)序列、单次激发快速自旋回波(SSFSE)序列、快速反转恢复运动抑制(FIRM)序列以及动态FIESTA序列,行胎儿颅脑、胸部腹部常规及胸部(肺、心脏)重点冠状面、矢状面及横断面扫描,将产前MRI、超声表现与出生后影像表现或手术(n=49)、引产后尸体解剖结果 (n=8)对照.结果 原发性心脏位置异常即右位心5例;继发性心脏位置异常52例,其中右肺发育不良7例、先天性膈疝(CDH)18例、先天性肺囊腺瘤样畸形(CCAM)24例、支气管肺隔离症(BPS)2例和纵隔占位1例.结论 MRI各序列综合应用在胎儿胸腔异常心脏位置及病因诊断方面其有一定的应用价值;FIESTA序列同一切面能同时显示异常心脏位置和导致其异常的胸部其他病变,动态FIESTA序列能动态显示较明显的心脏血流异常;SSFSE和FIRM序列能较好显示引起心脏位置异常的其他胸部病变.%Objective To explore the diagnostic value of magnetic resonance imaging ( MR!) on fetal cardiac malposition. Methods MRI examinations were performed 24 to 48 h after routine ultrasound examinations on 57 pregnant women with gestation of 20 to 36 weeks. The imaging protocols included 2 dimension fast imaging employing steady-state acquisition (2D FIESTA), single-shot fast spin echo (SSFSE), T, -weighted fast inversion recovery motion insensitive (FIRM) and dynamic FIESTA sequences in the axial, frontal and sagittal planes relative to the fetal brain, thorax, abdomen, especially lung and heart. Prenatal ultrasound and MRI findings were compared with postnatal diagnoses (n = 49) or autopsy ( n = 8). Postnatal evaluation included a variety of imaging and surgery. Results There were 5 cases of primary fetal cardiac

  6. Use of a semi-automated cardiac segmentation tool improves reproducibility and speed of segmentation of contaminated right heart magnetic resonance angiography.

    Science.gov (United States)

    Tandon, Animesh; Byrne, Nicholas; Nieves Velasco Forte, Maria de Las; Zhang, Song; Dyer, Adrian K; Dillenbeck, Jeanne M; Greil, Gerald F; Hussain, Tarique

    2016-08-01

    Three-dimensional printing has an increasing number of clinical applications in pediatric cardiology. Time required for dataset segmentation and conversion to stereolithography (STL) format remains a significant limitation. We investigated the impact of semi-automated cardiovascular-specific segmentation software on time and reproducibility of segmentation. Magnetic resonance angiograms (MRAs) of 19 patients undergoing intervention for right ventricular outflow lesions were segmented to demonstrate the right heart. STLs were created by two independent clinicians using semi-automated cardiovascular segmentation (SAS) and traditional manual segmentation (MS). Time was recorded and geometric STL disagreement was determined (0 % = no disagreement, 100 % = complete disagreement). MRA datasets were categorized as clean when only right heart structures were present in the MRA, or contaminated when left heart structures were also present and required removal. Eighteen (seven clean and 11 contaminated) cases were successfully segmented with both methods. Time to STL for clean datasets was faster with MS than SAS [median 209 s (IQR 192-252) vs. 296 s (272-317), p = 0.018] while contaminated datasets were faster with SAS [455 s (384-561) vs. 866 s (310-1429), p = 0.033]. Interobserver STL geometric disagreement was significantly lower using SAS than MS overall (0.70 ± 1.15 % vs. 1.31 ± 1.52 %, p = 0.030), and for the contaminated subset (0.81 ± 1.08 % vs. 1.75 ± 1.57 %, p = 0.036). Most geometric disagreement occurred at areas where left heart contamination was removed. Semi-automated segmentation was faster and more reproducible for contaminated datasets, while MS was faster but equally reproducible for clean datasets. Semi-automated segmentation methods are preferable for contaminated datasets and continued refinement of these tools should be supported. PMID:27173489

  7. 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 ...

  8. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... Safety En Español More Info Images/Videos News Physician Resources Professions Site Index A-Z Magnetic Resonance ... allergic reaction than iodinated contrast material. Tell your doctor about any health problems, recent surgeries or allergies ...

  9. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... Español More Info Images/Videos News Physician Resources Professions Site Index A-Z Magnetic Resonance Imaging (MRI) - ... into the bloodstream. The radiologist , technologist or a nurse may ask if you have allergies of any ...

  10. Left Ventricle: Fully Automated Segmentation Based on Spatiotemporal Continuity and Myocardium Information in Cine Cardiac Magnetic Resonance Imaging (LV-FAST

    Directory of Open Access Journals (Sweden)

    Lijia Wang

    2015-01-01

    Full Text Available CMR quantification of LV chamber volumes typically and manually defines the basal-most LV, which adds processing time and user-dependence. This study developed an LV segmentation method that is fully automated based on the spatiotemporal continuity of the LV (LV-FAST. An iteratively decreasing threshold region growing approach was used first from the midventricle to the apex, until the LV area and shape discontinued, and then from midventricle to the base, until less than 50% of the myocardium circumference was observable. Region growth was constrained by LV spatiotemporal continuity to improve robustness of apical and basal segmentations. The LV-FAST method was compared with manual tracing on cardiac cine MRI data of 45 consecutive patients. Of the 45 patients, LV-FAST and manual selection identified the same apical slices at both ED and ES and the same basal slices at both ED and ES in 38, 38, 38, and 41 cases, respectively, and their measurements agreed within -1.6±8.7 mL, -1.4±7.8 mL, and 1.0±5.8% for EDV, ESV, and EF, respectively. LV-FAST allowed LV volume-time course quantitatively measured within 3 seconds on a standard desktop computer, which is fast and accurate for processing the cine volumetric cardiac MRI data, and enables LV filling course quantification over the cardiac cycle.

  11. Magnetometer of nuclear magnetic resonance

    International Nuclear Information System (INIS)

    We present a nuclear magnetic resonance magnetometer that measures magnetic fields, between 2,500 gauss and 5,000 gauss, with an accuracy of a few parts per million. The circuit of the magnetometer, based on a marginal oscillator, permits a continuous tunning in the frequency range comprised between 10.0 MHz, with a signal to noise ratio of about 20. The radiofrequency amplifier is of the cascode type in integrated circuit and it operates with two 9V batteries. The modulation is at 35 Hz and it is provided by an external oscillator. The instrument is compact, inexpensive and easy to operate; it can also be used for didactic purposes to show the phenomenon of magnetic nuclear resonance and its main characteristics. (author)

  12. Your Radiologist Explains Magnetic Resonance Angiography (MRA)

    Science.gov (United States)

    ... produced 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 ...

  13. 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.

  14. Validation of 4D-MSPECT and QGS for quantification of left ventricular volumes and ejection fraction from gated 99mTc-MIBI SPET: comparison with cardiac magnetic resonance imaging

    International Nuclear Information System (INIS)

    The main aim of this study was to validate the accuracy of 4D-MSPECT in the assessment of left ventricular (LV) end-diastolic/end-systolic volumes (EDV, ESV) and ejection fraction (LVEF) from gated technetium-99m methoxyisobutylisonitrile single-photon emission tomography (99mTc-MIBI SPET), using cardiac magnetic resonance imaging (cMRI) as the reference method. By further comparing 4D-MSPECT and QGS with cMRI, the software-specific characteristics were analysed to elucidate clinical applicability. Fifty-four patients with suspected or proven coronary artery disease (CAD) were examined with gated 99mTc-MIBI SPET (8 gates/cardiac cycle) about 60 min after tracer injection at rest. LV EDV, ESV and LVEF were calculated from gated 99mTc-MIBI SPET using 4D-MSPECT and QGS. On the same day, cMRI (20 gates/cardiac cycle) was performed, with LV EDV, ESV and LVEF calculated using Simpson's rule. Both algorithms worked with all data sets. Correlation between the results of gated 99mTc-MIBI SPET and cMRI was high for EDV [R=0.89 (4D-MSPECT), R=0.92 (QGS)], ESV [R=0.96 (4D-MSPECT), R=0.96 (QGS)] and LVEF [R=0.89 (4D-MSPECT), R=0.90 (QGS)]. In contrast to ESV, EDV was significantly underestimated by 4D-MSPECT and QGS compared to cMRI [130±45 ml (4D-MSPECT), 122±41 ml (QGS), 139±36 ml (cMRI)]. For LVEF, 4D-MSPECT and cMRI revealed no significant differences, whereas QGS yielded significantly lower values than cMRI [57.5%±13.7% (4D-MSPECT), 52.2%±12.4% (QGS), 60.0%±15.8% (cMRI)]. In conclusion, agreement between gated 99mTc-MIBI SPET and cMRI is good across a wide range of clinically relevant LV volume and LVEF values assessed by 4D-MSPECT and QGS. However, algorithm-varying underestimation of LVEF should be accounted for in the clinical context and limits interchangeable use of software. (orig.)

  15. Determinants of Discrepancies in Detection and Comparison of the Prognostic Significance of Left Ventricular Hypertrophy by Electrocardiogram and Cardiac Magnetic Resonance Imaging

    OpenAIRE

    Bacharova, Ljuba; Chen, Haiying; Estes, E. Harvey; Mateasik, Anton; Bluemke, David A.; Lima, Joao A. C.; Burke, Gregory L; Soliman, Elsayed Z

    2014-01-01

    Despite the low sensitivity of the electrocardiogram (ECG) in detecting left ventricular hypertrophy (LVH), ECG-LVH is known to be a strong predictor of cardiovascular risk. Understanding reasons for the discrepancies in detection of LVH by ECG versus imaging could help improve the diagnostic ability of ECG. We examined factors associated with false-positive and false-negative ECG-LVH, using cardiac MRI as the gold standard. We also compared the prognostic significance of ECG-LVH and MRI-LVH ...

  16. Magnetic-resonance velocity mapping of the central circulation

    DEFF Research Database (Denmark)

    Søndergaard, Lise

    1994-01-01

    flow profile during the cardiac cycle can be determined. This allows quantification of forward flow, regurgitant volume and regurgitant fraction in cases of heart-valve insufficiency. In valvular stenosis the transvalvular pressure gradient and valve area can be determined. Magnetic-resonance velocity......In magnetic-resonance (MR) velocity mapping there exists a linear relationship between the velocity and signal in each element of a tomographic image. The technique can be used for quantitative measurements of linear velocities (m s-1) and flow rates (1 min-1). By using cinematographic images the...

  17. Optically detected magnetic resonance imaging

    International Nuclear Information System (INIS)

    Optically detected magnetic resonance provides ultrasensitive means to detect and image a small number of electron and nuclear spins, down to the single spin level with nanoscale resolution. Despite the significant recent progress in this field, it has never been combined with the power of pulsed magnetic resonance imaging techniques. Here, we demonstrate how these two methodologies can be integrated using short pulsed magnetic field gradients to spatially encode the sample. This result in what we denote as an 'optically detected magnetic resonance imaging' technique. It offers the advantage that the image is acquired in parallel from all parts of the sample, with well-defined three-dimensional point-spread function, and without any loss of spectroscopic information. In addition, this approach may be used in the future for parallel but yet spatially selective efficient addressing and manipulation of the spins in the sample. Such capabilities are of fundamental importance in the field of quantum spin-based devices and sensors

  18. Cardiovascular magnetic resonance in hypertrophic cardiomyopathy

    Energy Technology Data Exchange (ETDEWEB)

    Shiozaki, Afonso Akio; Parga, Jose Rodrigues; Arteaga, Edmundo; Rochitte, Carlos Eduardo [Sao Paulo Univ. (USP), SP (Brazil). Instituto do Coracao. Setor de Tomografia Computarizada e Ressonancia Magnetica Cardiovascular]. E-mail: rochitte@incor.usp.br; Kim, Raymond J. [Duke Cardiovascular Magnetic Resonance Center, Durham, NC (United States); Tassi, Eduardo Marinho [Diagnosticos da America S.A., Rio de Janeiro, RJ (Brazil). Sector of Cardiovascular Magnetic Resonance and Computed Tomography

    2007-03-15

    Hypertrophic cardiomyopathy (HCM) is the most frequent genetic cardiac disease that causes sudden death in young people, with an incidence of 1:500 adults. The routinely used criteria for worst prognosis have limited sensitivity and specificity. Thus, the estimated risk of evolving to dilated cardiomyopathy or sudden death is somewhat inaccurate, leading to management uncertainty of HCM patients. Therefore, an accurate noninvasive method for the diagnosis of HCM with prognostic value is of great importance. In the last years, Cardiovascular Magnetic Resonance (CMR) emerged not only as a diagnostic tool, but also as a study with prognostic values, by characterizing myocardial fibrosis with great accuracy in HCM patients. Additionally, CMR identifies the types of hypertrophy, analyses the ventricular function, estimates the intraventricular gradient and allows the determination of differential diagnosis. Moreover, CMR can uniquely access myocardial fibrosis in HCM. (author)

  19. Resonant magnetic fields from inflation

    International Nuclear Information System (INIS)

    We propose a novel scenario to generate primordial magnetic fields during inflation induced by an oscillating coupling of the electromagnetic field to the inflaton. This resonant mechanism has two key advantages over previous proposals. First of all, it generates a narrow band of magnetic fields at any required wavelength, thereby allaying the usual problem of a strongly blue spectrum and its associated backreaction. Secondly, it avoids the need for a strong coupling as the coupling is oscillating rather than growing or decaying exponentially. Despite these major advantages, we find that the backreaction is still far too large during inflation if the generated magnetic fields are required to have a strength of O(10−15 Gauss) today on observationally interesting scales. We provide a more general no-go argument, proving that this problem will apply to any model in which the magnetic fields are generated on subhorizon scales and freeze after horizon crossing

  20. Low dose prospective ECG-gated delayed enhanced dual-source computed tomography in reperfused acute myocardial infarction comparison with cardiac magnetic resonance

    International Nuclear Information System (INIS)

    Purpose: To determine whether prospective electrocardiogram (ECG)-gated delayed contrast-enhanced dual-source computed tomography (DCE-DSCT) can accurately delineate the extension of myocardial infarction (MI) compared with delayed enhanced cardiac MR (DE-MR). Material and methods: Eleven patients were examined using dual-source CT and cardiac MR in 2 weeks after a first reperfused MI. DCE-DSCT scan protocol was performed with prospective ECG-gating sequential scan model 7 min after contrast administration. In a 17-model, infarcted myocardium detected by DE-MR was categorized as transmural and subendocardial extension. Segment of infarcted location and graded transmurality were compared between DCE-MDCT and DE-MR. Results: In all eleven patients, diagnostic quality was obtained for depicting delayed enhanced myocardium. Agreement between DCE-DSCT and MR was good on myocardial segment based comparison (kappa = 0.85, p < 0.001), and on transmural and subendocardial infarction type comparison (kappa = 0.82, p < 0.001, kappa = 0.52, p < 0.001, respectively). CT value was higher on infarcted region than that of normal region (100.02 ± 9.57 HU vs. 72.63 ± 7.32 HU, p < 0.001). Radiation dose of prospectively ECG-gating protocol were 0.99 ± 0.08 mSv (0.82-1.19 mSv). Conclusions: Prospective ECG-gated DCE-DSCT can accurately assess the extension and the patterns of myocardial infarction with low radiation dose.

  1. Low dose prospective ECG-gated delayed enhanced dual-source computed tomography in reperfused acute myocardial infarction comparison with cardiac magnetic resonance

    Energy Technology Data Exchange (ETDEWEB)

    Wang Rui, E-mail: rui_wang1979@yahoo.cn [Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, 100029 Beijing (China); Zhang Zhaoqi, E-mail: zhaoqi5000@vip.sohu.com [Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, 100029 Beijing (China); Xu Lei, E-mail: leixu2001@hotmail.com [Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, 100029 Beijing (China); Ma Qin, E-mail: tel1367@gmail.com [Department of Emergency, Beijing Anzhen Hospital, Capital Medical University, 100029 Beijing (China); He Yi, E-mail: heyi139@sina.com [Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, 100029 Beijing (China); Lu Dongxu, E-mail: larry.hi@163.com [Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, 100029 Beijing (China); Yu Wei, E-mail: yuwei02@gmail.com [Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, 100029 Beijing (China); Fan Zhanming, E-mail: fanzm120@tom.com [Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, 100029 Beijing (China)

    2011-11-15

    Purpose: To determine whether prospective electrocardiogram (ECG)-gated delayed contrast-enhanced dual-source computed tomography (DCE-DSCT) can accurately delineate the extension of myocardial infarction (MI) compared with delayed enhanced cardiac MR (DE-MR). Material and methods: Eleven patients were examined using dual-source CT and cardiac MR in 2 weeks after a first reperfused MI. DCE-DSCT scan protocol was performed with prospective ECG-gating sequential scan model 7 min after contrast administration. In a 17-model, infarcted myocardium detected by DE-MR was categorized as transmural and subendocardial extension. Segment of infarcted location and graded transmurality were compared between DCE-MDCT and DE-MR. Results: In all eleven patients, diagnostic quality was obtained for depicting delayed enhanced myocardium. Agreement between DCE-DSCT and MR was good on myocardial segment based comparison (kappa = 0.85, p < 0.001), and on transmural and subendocardial infarction type comparison (kappa = 0.82, p < 0.001, kappa = 0.52, p < 0.001, respectively). CT value was higher on infarcted region than that of normal region (100.02 {+-} 9.57 HU vs. 72.63 {+-} 7.32 HU, p < 0.001). Radiation dose of prospectively ECG-gating protocol were 0.99 {+-} 0.08 mSv (0.82-1.19 mSv). Conclusions: Prospective ECG-gated DCE-DSCT can accurately assess the extension and the patterns of myocardial infarction with low radiation dose.

  2. Pediatric Body Magnetic Resonance Imaging.

    Science.gov (United States)

    Kandasamy, Devasenathipathy; Goyal, Ankur; Sharma, Raju; Gupta, Arun Kumar

    2016-09-01

    Magnetic resonance imaging (MRI) is a radiation-free imaging modality with excellent contrast resolution and multiplanar capabilities. Since ionizing radiation is an important concern in the pediatric population, MRI serves as a useful alternative to computed tomography (CT) and also provides additional clues to diagnosis, not discernible on other investigations. Magnetic resonance cholangiopancreatography (MRCP), urography, angiography, enterography, dynamic multiphasic imaging and diffusion-weighted imaging provide wealth of information. The main limitations include, long scan time, need for sedation/anesthesia, cost and lack of widespread availability. With the emergence of newer sequences and variety of contrast agents, MRI has become a robust modality and may serve as a one-stop shop for both anatomical and functional information. PMID:26916887

  3. 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 to char...... a new road to a better understanding of the evanescent waves component in NMR with the opportunity to perform localized spectroscopy and imaging....

  4. Magnetic resonance imaging derived left ventricular global and region function parameters in healthy adults

    Institute of Scientific and Technical Information of China (English)

    穆莉莎

    2014-01-01

    Objective To establish cardiac magnetic resonance imaging(MRI)derived left ventricular(LV)global and region function parameters in normal adults.Methods Twenty normal adults were examined with fast imaging employing steady-state(Fiesta)acquisition sequence of cardiac MRI,LV global function and LV region function were measured at basal,middle,apical level and at 16

  5. Cardiovascular magnetic resonance and PET-CT of left atrial paraganglioma

    OpenAIRE

    Ruehm Stefan; Lai Chi; Tomasian Anderanik; Krishnam Mayil S

    2010-01-01

    Abstract Cardiac paragangliomas are among the rarest primary cardiac tumors. We present a case of left atrial paraganglioma in a patient who presented with symptoms and signs of catecholamine excess in which cardiovascular magnetic resonance in multiple orientations and PET-CT played an important role in the diagnosis and tissue characterization.

  6. Tomography by nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Imaging methods based on nuclear magnetic resonance allow the production of sectional images of the human body without ionizing radiation. It is possible to measure the density and relaxation times of the water protons in body fluids or tissue. This allows not only to obtain morphological information but also to get some insight into the spatial distribution of physiological data. Starting with a review of the principles of nuclear magnetic resonance it is explained how the measured signal can be associated with an image point; it is also explained what type of apparatus is necessary and what the physical limitations are. Possible risks the patient may be exposed to in an examination using nuclear magnetic resonance are discussed. The present state of the technical development enables the production of whole-body sectional images of a living person within about one minute. By means of some typical examples the nature and properties of these images are explained. Although extensive clinical studies will be necessary before a more general assessment can be made of this method, an outlook is provided on expected further developments and possible future fields of application. (orig.)

  7. Magnetic Resonance Force Detection using a Membrane Resonator

    OpenAIRE

    Scozzaro, Nicolas; Ruchotzke, Will; Belding, Amanda; Cardellino, Jeremy D.; Blomberg, Erick C.; McCullian, Brendan A.; Bhallamudi, Vidya P.; Pelekhov, Denis V.; Hammel, P. Chris

    2016-01-01

    The availability of compact, low-cost magnetic resonance imaging instruments would further broaden the substantial impact of this technology. We report highly sensitive detection of magnetic resonance using low-stress silicon nitride (SiN$_x$) membranes. We use these membranes as low-loss, high-frequency mechanical oscillators and find they are able to mechanically detect spin-dependent forces with high sensitivity enabling ultrasensitive magnetic resonance detection. The high force detection...

  8. Automatic slice-alignment method in cardiac magnetic resonance imaging for evaluation of the right ventricle in patients with pulmonary hypertension

    Science.gov (United States)

    Yokoyama, Kenichi; Nitta, Shuhei; Kuhara, Shigehide; Ishimura, Rieko; Kariyasu, Toshiya; Imai, Masamichi; Nitatori, Toshiaki; Takeguchi, Tomoyuki; Shiodera, Taichiro

    2015-09-01

    We propose a new automatic slice-alignment method, which enables right ventricular scan planning in addition to the left ventricular scan planning developed in our previous work, to simplify right ventricular cardiac scan planning and assess its accuracy and the clinical acceptability of the acquired imaging planes in the evaluation of patients with pulmonary hypertension. Steady-state free precession (SSFP) sequences covering the whole heart in the end-diastolic phase with ECG gating were used to acquire 2D axial multislice images. To realize right ventricular scan planning, two morphological feature points are added to be detected and a total of eight morphological features of the heart were extracted from these series of images, and six left ventricular planes and four right ventricular planes were calculated simultaneously based on the extracted features. The subjects were 33 patients (25 with chronic thromboembolic pulmonary hypertension and 8 with idiopathic pulmonary arterial hypertension). The four right ventricular reference planes including right ventricular short-axis, 4-chamber, 2-chamber, and 3-chamber images were evaluated. The acceptability of the acquired imaging planes was visually evaluated using a 4-point scale, and the angular differences between the results obtained by this method and by conventional manual annotation were measured for each view. The average visual scores were 3.9±0.4 for short-axis images, 3.8±0.4 for 4-chamber images, 3.8±0.4 for 2-chamber images, and 3.5±0.6 for 3-chamber images. The average angular differences were 8.7±5.3, 8.3±4.9, 8.1±4.8, and 7.9±5.3 degrees, respectively. The processing time was less than 2.5 seconds in all subjects. The proposed method, which enables right ventricular scan planning in addition to the left ventricular scan planning developed in our previous work, can provide clinically acceptable planes in a short time and is useful because special proficiency in performing cardiac MR for

  9. Automatic slice-alignment method in cardiac magnetic resonance imaging for evaluation of the right ventricle in patients with pulmonary hypertension

    Directory of Open Access Journals (Sweden)

    Kenichi Yokoyama

    2015-09-01

    Full Text Available We propose a new automatic slice-alignment method, which enables right ventricular scan planning in addition to the left ventricular scan planning developed in our previous work, to simplify right ventricular cardiac scan planning and assess its accuracy and the clinical acceptability of the acquired imaging planes in the evaluation of patients with pulmonary hypertension. Steady-state free precession (SSFP sequences covering the whole heart in the end-diastolic phase with ECG gating were used to acquire 2D axial multislice images. To realize right ventricular scan planning, two morphological feature points are added to be detected and a total of eight morphological features of the heart were extracted from these series of images, and six left ventricular planes and four right ventricular planes were calculated simultaneously based on the extracted features. The subjects were 33 patients (25 with chronic thromboembolic pulmonary hypertension and 8 with idiopathic pulmonary arterial hypertension. The four right ventricular reference planes including right ventricular short-axis, 4-chamber, 2-chamber, and 3-chamber images were evaluated. The acceptability of the acquired imaging planes was visually evaluated using a 4-point scale, and the angular differences between the results obtained by this method and by conventional manual annotation were measured for each view. The average visual scores were 3.9±0.4 for short-axis images, 3.8±0.4 for 4-chamber images, 3.8±0.4 for 2-chamber images, and 3.5±0.6 for 3-chamber images. The average angular differences were 8.7±5.3, 8.3±4.9, 8.1±4.8, and 7.9±5.3 degrees, respectively. The processing time was less than 2.5 seconds in all subjects. The proposed method, which enables right ventricular scan planning in addition to the left ventricular scan planning developed in our previous work, can provide clinically acceptable planes in a short time and is useful because special proficiency in performing

  10. Ultra-high frequency magnetic resonance imaging

    OpenAIRE

    Magill, Arthur W.

    2007-01-01

    This thesis addresses the problem of radiofrequency probe design for Ultra High Frequency Magnetic Resonance Imaging (7T). The signal-to-noise ratio available in Magnetic Resonance Imaging (MRI) is determined by the static magnetic field strength, causing a continued drive toward higher fields to enable faster image acquisition at finer spatial resolution. The resonant frequency increases linearly with static field strength. At 7T the proton resonant frequency is 300MHz, with a wavelength...

  11. Magnetic resonance imaging in oncology

    International Nuclear Information System (INIS)

    Nuclear magnetic resonance (NMR) employs radio-frequency radiation in the presence of a static magnetic field to produce signals from naturally occurring nuclei in biological tissue. The information in magnetic resonance imaging (MRI) can be derived from these signals in any orthogonal plane. Hydrogen is the most abundant of such nuclei, occurring naturally in water and lipid, and can be detected at relatively low magnetic field strength (0.04 tesla (T) upwards). The MR signal from hydrogen depends not only on the proton density and the T1 and T2 relaxation times of those protons following radio-frequency pulse disturbances, but also on the timing parameters of the radio-frequency pulse sequences employed. Image contrast depends on the interaction between all these factors; not simply as in X-ray computed tomography (CT) on the properties of the tissue itself. Therefore an understanding of both the imaging process and the pathology under investigation is essential in the proper use of MRI

  12. Value of nuclear magnetic resonance imaging in cardiology

    International Nuclear Information System (INIS)

    The present study summarizes an experience with Magnetic Resonance Imaging (MRI) in the evaluation of twelve patients with a variety of cardiac abnormalities (myocardial infarction, mural thrombi, obstructive cardiomyopathy, pericarditis). The results are compared with clinical data, with measurements from other techniques such as two-dimensional echocardiography and with the images in normal subjects. An anticipated advantage of MRI is the ability to provide better tissue characterization, than has been attained with other imaging techniques, by relaxation time measurement

  13. The diagnosis of hypertrophic cardiomyopathy by cardiovascular magnetic resonance

    OpenAIRE

    Noureldin Radwa A; Liu Songtao; Nacif Marcelo S; Judge Daniel P; Halushka Marc K; Abraham Theodore P; Ho Carolyn; Bluemke David A

    2012-01-01

    Abstract Hypertrophic cardiomyopathy (HCM) is the most common genetic disease of the heart. HCM is characterized by a wide range of clinical expression, ranging from asymptomatic mutation carriers to sudden cardiac death as the first manifestation of the disease. Over 1000 mutations have been identified, classically in genes encoding sarcomeric proteins. Noninvasive imaging is central to the diagnosis of HCM and cardiovascular magnetic resonance (CMR) is increasingly used to characterize morp...

  14. Value of black blood T2* cardiovascular magnetic resonance

    OpenAIRE

    Carpenter John Paul; Smith Gillian C; He Taigang; Alam Mohammed H; Firmin David N; Pennell Dudley J

    2011-01-01

    Abstract Purpose To assess whether black blood T2* cardiovascular magnetic resonance is superior to conventional white blood imaging of cardiac iron in patients with thalassaemia major (TM). Materials and methods We performed both conventional white blood and black blood T2* CMR sequences in 100 TM patients to determine intra and inter-observer variability and presence of artefacts. In 23 patients, 2 separate studies of both techniques were performed to assess interstudy reproducibility. Resu...

  15. Heart valve disease: investigation by cardiovascular magnetic resonance

    OpenAIRE

    Myerson Saul G

    2012-01-01

    Abstract Cardiovascular magnetic resonance (CMR) has become a valuable investigative tool in many areas of cardiac medicine. Its value in heart valve disease is less well appreciated however, particularly as echocardiography is a powerful and widely available technique in valve disease. This review highlights the added value that CMR can bring in valve disease, complementing echocardiography in many areas, but it has also become the first-line investigation in some, such as pulmonary valve di...

  16. Visualization of coronary venous anatomy by cardiovascular magnetic resonance

    OpenAIRE

    Crean Andrew; Plein Sven; Younger John F; Ball Stephen G; Greenwood John P

    2009-01-01

    Abstract Background Coronary venous imaging with whole-heart cardiovascular magnetic resonance (CMR) angiography has recently been described using developmental pulse sequences and intravascular contrast agents. However, the practical utility of coronary venous imaging will be for patients with heart failure in whom cardiac resynchronisation therapy (CRT) is being considered. As such complementary information on ventricular function and myocardial viability will be required. The aim of this s...

  17. Complementarity of magnetic resonance spectroscopy, positron emission tomography and single photon emission tomography for the in vivo investigation of human cardiac metabolism and neurotransmission

    International Nuclear Information System (INIS)

    PET is quantitative and very sensitive, and therefore only tracer amounts of molecules need to be injected. It allows neurotransmitters and receptors to be studied and a global view of metabolism to oxygen consumption, glucose and fatty acid utilization to be obtained. SPET also has good sensitivity, but uses gamma-emitting isotopes of heteroatoms. Their longer half-lives allow follow-up for hours or days. MRS is based on stable elements with high or low natural abundance. It has very low sensitivity and only millimolar concentrations of substrates can be detected, but various parts of metabolism can be studied. The in vivo measurement of myocardial concentration of substances has many problems that are common to all three techniques. The complementarity of the techniques is illustrated by their applications to the study of cardiac metabolism. For instance, the energy metabolism can be studied by 31P-MRS, which detects the high-energy compounds ATP and phosphocreatine, and 13C-MRS yields information on the tricarboxylic acid cycle activity. PET and SPET allow the utilization of fatty acids, the normal fuels of the heart, to be studied. During ischaemia, PET with 18F-fluorodeoxyglucose can determine the glucose consumption and 1H-MRS shows the increase in lactic acid, reflecting anaerobic glycolysis. Comparison of the use of acetate labelled with 11C for PET or 13C for MRS shows the potentials and limitations of each technique. Myocardial perfusion can be evaluated directly with various PET tracers or indirectly with thallium 201 or various technetium-99m-labelled tracers by SPET. No MRS marker of perfusion is so far clinically available. Mainly SPET and PET are used clinically for the investigation of ischaemic heart disease as well as cardiomyophathies, but some initial results using 31P-MRS are being obtained. (orig./MG)

  18. Application of Cardiac Magnetic Resonance Imaging in Radiofrequency Ablation of Atrial Fibrilla-tion%心脏磁共振成像在心房颤动消融手术前后的应用

    Institute of Scientific and Technical Information of China (English)

    陈明鲜(综述); 周胜华(审校)

    2015-01-01

    随着科学的进步、技术的发展,射频消融已成为治疗心房颤动的重要手段,其在心房颤动的治疗中起举足轻重作用,但仍有部分患者消融术无效,其中一个主要原因系无法正确评估肺静脉和左心房结构。心脏磁共振成像( cMRI)具有高分辨率的优点,能准确地评估软组织结构,cMRI近年来运用于心房颤动评估逐渐增多,有助于提高心房颤动射频消融成功率和减少手术并发症。%With the development of current technology, radiofrequency ablation has become a critical treatment method for atrial fibrillation .Radiofrequency ablation plays a pivotal role in atrial fibrillation thera-py,however,it still remains ineffective to a few patients .One of the main shortcoming is its inability to cor-rectly assess the structure of pulmonary vein and left atrium .The major advantages of cardiac magnetic reso-nance imaging(cMRI) are is the high temporal and spatial resolution and the ability to characterize the com-position of soft tissues,therefore,cMRI has been gradually used to assess atrial fibrillation in order to improve ablation outcome and reduce complications .

  19. Fast magnetization reversal of nanoclusters in resonator

    OpenAIRE

    Yukalov, V. I.; Yukalova, E. P.

    2012-01-01

    An effective method for ultrafast magnetization reversal of nanoclusters is suggested. The method is based on coupling a nanocluster to a resonant electric circuit. This coupling causes the appearance of a magnetic feedback field acting on the cluster, which drastically shortens the magnetization reversal time. The influence of the resonator properties, nanocluster parameters, and external fields on the magnetization dynamics and reversal time is analyzed. The magnetization reversal time can ...

  20. Wide-range nuclear magnetic resonance detector

    Science.gov (United States)

    Sturman, J. C.; Jirberg, R. J.

    1972-01-01

    Compact and easy to use solid state nuclear magnetic resonance detector is designed for measuring field strength to 20 teslas in cryogenically cooled magnets. Extremely low noise and high sensitivity make detector applicable to nearly all types of analytical nuclear magnetic resonance measurements and can be used in high temperature and radiation environments.

  1. Hyperpolarized Renal Magnetic Resonance Imaging

    DEFF Research Database (Denmark)

    Laustsen, Christoffer

    2016-01-01

    The introduction of dissolution dynamic nuclear polarization (d-DNP) technology has enabled a new paradigm for renal imaging investigations. It allows standard magnetic resonance imaging complementary renal metabolic and functional fingerprints within seconds without the use of ionizing radiation....... Increasing evidence supports its utility in preclinical research in which the real-time interrogation of metabolic turnover can aid the physiological and pathophysiological metabolic and functional effects in ex vivo and in vivo models. The method has already been translated to humans, although the clinical...

  2. 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

  3. Evanescent Waves Nuclear Magnetic Resonance.

    Science.gov (United States)

    Halidi, El Mohamed; Nativel, Eric; Akel, Mohamad; Kenouche, Samir; Coillot, Christophe; Alibert, Eric; Jabakhanji, Bilal; Schimpf, Remy; Zanca, Michel; Stein, Paul; Goze-Bac, Christophe

    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 to characterize and model evanescent electromagnetic fields originating from NMR phenomenon. We report that in this experimental configuration the available NMR signal is one order of magnitude larger and follows an exponential decay inversely proportional to the size of the emitters. Those investigations open a new road to a better understanding of the evanescent waves component in NMR with the opportunity to perform localized spectroscopy and imaging. PMID:26751800

  4. Cardiac MRI in Athletes

    NARCIS (Netherlands)

    Luijkx, T.

    2012-01-01

    Cardiac magnetic resonance imaging (CMR) is often used in athletes to image cardiac anatomy and function and is increasingly requested in the context of screening for pathology that can cause sudden cardiac death (SCD). In this thesis, patterns of cardiac adaptation to sports are investigated with C

  5. The Clinic Application of Cardiac Magnetic Resonance Imaging in Evaluation the Cardiac Function Combined with Echocardiography%心脏磁共振结合心脏超声对左心室功能评价的临床应用

    Institute of Scientific and Technical Information of China (English)

    杨向峰; 董光; 耿海; 葛敏; 方龙江

    2015-01-01

    目的:应用心脏磁共振( CMR)评价左心室功能,并通过对比UCG探讨CMR在临床中的应用价值。方法选取行CMR检查患者22例,采用Siemens Magnetom Skyra 3.0 T超导型磁共振仪进行扫描,均进行MR平扫、电影扫描,所有检查者行CMR前均行超声心动图检查。结果对比CMR和超声心动图测量所得EDV,ESV,EF值,CMR测量EDV,EF值较超声心动图略低,ESV值高于超声心动图。两组间EDV,ESV值无统计学意义(P>0.05),EF值具有统计学差异(P<0.05)。结论 CMR在评价左心室功能方面准确性及可靠性好,评价指标全面,可应用于各种复杂疾病心脏功能的检查。%Objective To evaluate the left ventricular function by cardiac magnetic resonance imaging( CMR) ,and to explore the fesibility and value of CMR in clinical application.Methods The lefe ventricular function of twenty-two patients were evaluated by Siemens Magnetom Skyra 3.0T magnetic resonance Machine.Before that,all patients underwent echocardiographic measurements.Results The value of EDV,ESV,EF measured by CMR and echocardiography showed the EDV,EF measured by CMR was slightly lower than the value meas-ured by echocardiography;The ESV measured by CMR was slightly higher than the value measured by echocardiography.Linear correlation a-nalysis of the two methods were highly correlated(r=0.843-0.936).The consistency was also higher.The value of EDV,ESV had no statisti-cal significance(P>0.05).While the value of EF was statistically significant(P<0.05).Conclusion CMR shows the left ventricular func-tion with good accuracy,reliability and comprehensive assessment criteria,and can be used to check cardiac function in a variety of complex diseases.

  6. Endocardium and epicardium segmentation of left ventricle in cardiac magnetic resonance images based on directional Snake model%基于方向Snake模型的心脏磁共振图像左心室内外膜分割

    Institute of Scientific and Technical Information of China (English)

    张宁; 余学飞; 卢广文

    2012-01-01

    Concerning that the edges of the endocardium and epicardium of the left ventricle in the cardiac Magnetic Resonance Imaging ( MR1) images have different directions, a new directional active contour model in curve evolution framework was proposed for segmentation of endocardium and epicardium of the left ventricle. The curve evolution equation included a hybrid geometric flow with edge and region gray characteristics that were obtained from the image itself. The edge-based term in the geometric flow borrowed from extended Dynamic Directional Gradient Vector Flow ( DDGVF) with fast marching method was utilized to guide the curve evolution towards the object boundaries with different direction. The region-based term borrowed from Chan-Vese (CV) model was utilized to prevent the curve from leakage under the influence of other edge components. The final curve evolution equation was dealt with level set method. The experimental results for gray and cardiac MRI images show that the proposed method can get better segmentation effects. It has certain application value for realizing myocardium auto-segmentation, evaluation and analysis of heart function based on cardiac MRI images.%针对心脏磁共振图像(MRI)左心室内膜与外膜边缘方向不同的特点,提出一种基于曲线演化框架的方向主动轮廓模型进行左心室内外膜分割.曲线演化方程中包含基于图像边缘与区域灰度特征的混合几何流.几何流中的边缘信息项由经Fast Marching方法扩展后的动态方向梯度矢量流场(DDGVF)构成,用以引导曲线向具有不同方向的目标边缘运动,而区域友度信息项则由Chan-Vese (CV)模型构成,用以防止曲线在演化过程中受其他边缘成分的影响而发生泄漏.最终的曲线演化方程采用水平集方法求解.实验结果表明,所提方法能够较为准确地分割出心脏MRI图像中的左心室内外膜并具有较好的鲁棒性,对于实现基于心脏MRI图像的左心室心

  7. 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.

  8. Magnetic resonance imaging of the brain in patients with cardiac pace makers. in-vitro- and in-vivo-evaluation at 1.5 Tesla

    International Nuclear Information System (INIS)

    Purpose: In-vitro and In-vivo evaluation of feasibility and safety of MRI of the brain at 1.5 T in patients with implanted pacemakers (PM). Materials and Methods: 24 PM models and 45 PM electrodes were tested In-vitro with respect to translational forces, heating of PM leads, behaviour of reed switch (activated vs. deactivated) and function at a 1.5 T MRI-system (actively shielded, maximum field gradient: 30 mT/m; rise time: 150 T/m/s). Based on these results, 63 MRI examinations in 45 patients with implanted PM were performed. Prior to MRI the PM were re-programmed in an asynchronous mode. The maximum SAR of MRI-sequences was limited to 1.2 W/kg. Continuous monitoring of ECG and pulse oximetry was performed during MRI. PM inquiry was performed prior to MRI, immediately after MRI and - to assess long-term damages - three months after the MRI exams, including determination of stimulation thresholds to assess potential thermal myocardial injuries at the lead tips. Results: Translational forces (Fmax≤560 mN) and temperature increase (ΔTmax≤2.98 C) were in a range which does not represent a safety concern from a biophysical point of view. No changes to the programmed parameters of the PM or damage of PM components were observed neither In-vitro (n=0/24) nor In-vivo (n=0/63). Despite the strong magnetic field, the reed switch remained deactivated in 54% (13/24) of the cases during In-vitro simulated MRI exams of the brain. All patient studies (n=63/63) could be completed without any complications. Atrial and ventricular stimulation thresholds (expressed as pulse duration at 2-fold rheobase) did not change significantly immediately post-MRI nor in the 3 months follow-up (pre-MRI: 0.17 ms±0.13 ms, post-MRI: 0.18 ms±0.14 ms, 3 months follow-up: 0.17 ms±0.12 ms). (orig.)

  9. Cerebellar hemangioblastoma: magnetic resonance findings

    International Nuclear Information System (INIS)

    To characterize the results of magnetic resonance imaging in cerebellar hemangioblastoma. This retrospective study deals with seven cases of histologically-confirmed cerebellar hemangioblastoma after surgery. Another patient, diagnosed as having Von Hippel-Lindau disease, also developed this lesions, but the finding was not histologically confirmed. In all, there were 2 women and 6 men. Three of these patients presented Von Hippel-Lindaus disease. All were studied on a 0.5 T imager with T1, T2 and PD-weighted spin-echo axial planes; T1-weighted sequences were repeated after intravenous gadolinium administration. According to their aspects, the lesions were divided into three groups as follows: cyst containing a mural nodule (n=3)solid tumor (n=3) and cavitated tumor (n=1). In one patient, the lesion was initially solid and was found to present cavitation two years later. Abnormal vascularization was observed in all the tumors except for two small solid tumors, and the findings were not clear in one of the cysts containing a mural nodule. In the differential diagnosis it may be difficult to rule out other tumors, such as cystic astrocytoma. However, magnetic resonance imaging, together with the clinical data, is of diagnostic value in the three morphological types of cerebellar hemangioblastoma. (Author) 15 refs

  10. Magnetic resonance imaging of hemochromatosis arthropathy

    International Nuclear Information System (INIS)

    This study was undertaken to compare plain film radiography and magnetic resonance imaging in the assessment of hemochromatosis arthropathy of the knees of ten patients with a biopsy-proven diagnosis. Both modalities enabled visualisation of bony degenerative changes; magnetic resonance imaging enabled additional visualization of deformity of both cartilage and menisci. Magnetic resonance imaging failed reliably to confirm the presence of intra-articular iron in the patients studied. No correlation was observed between synovial fluid magnetic resonance signal values, corresponding serum ferritin levels, or the severity of the observed degenerative changes. (orig.)

  11. 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).

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

    International Nuclear Information System (INIS)

    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).

  13. Cardiac magnetic resonance imaging in children

    Energy Technology Data Exchange (ETDEWEB)

    Helbing, Willem A. [Erasmus Medical Centre - Sophia Children' s Hospital, Department of Radiology, Rotterdam (Netherlands); Department of Paediatrics (Division of Cardiology), Sp-2.429, P.O. Box 2060, CB, Rotterdam (Netherlands); Ouhlous, Mohamed [Erasmus Medical Centre - Sophia Children' s Hospital, Department of Radiology, Rotterdam (Netherlands)

    2015-01-01

    MRI is an important additional tool in the diagnostic work-up of children with congenital heart disease. This review aims to summarise the role MRI has in this patient population. Echocardiography remains the main diagnostic tool in congenital heart disease. In specific situations, MRI is used for anatomical imaging of congenital heart disease. This includes detailed assessment of intracardiac anatomy with 2-D and 3-D sequences. MRI is particularly useful for assessment of retrosternal structures in the heart and for imaging large vessel anatomy. Functional assessment includes assessment of ventricular function using 2-D cine techniques. Of particular interest in congenital heart disease is assessment of right and single ventricular function. Two-dimensional and newer 3-D techniques to quantify flow in these patients are or will soon become an integral part of quantification of shunt size, valve function and complex flow patterns in large vessels. More advanced uses of MRI include imaging of cardiovascular function during stress and tissue characterisation of the myocardium. Techniques used for this purpose need further validation before they can become part of the daily routine of MRI assessment of congenital heart disease. (orig.)

  14. Magnetic Resonance Imaging of Electrolysis.

    Science.gov (United States)

    Meir, Arie; Hjouj, Mohammad; Rubinsky, Liel; Rubinsky, Boris

    2015-02-01

    This study explores the hypothesis that Magnetic Resonance Imaging (MRI) can image the process of electrolysis by detecting pH fronts. The study has relevance to real time control of cell ablation with electrolysis. To investigate the hypothesis we compare the following MR imaging sequences: T1 weighted, T2 weighted and Proton Density (PD), with optical images acquired using pH-sensitive dyes embedded in a physiological saline agar solution phantom treated with electrolysis and discrete measurements with a pH microprobe. We further demonstrate the biological relevance of our work using a bacterial E. Coli model, grown on the phantom. The results demonstrate the ability of MRI to image electrolysis produced pH changes in a physiological saline phantom and show that these changes correlate with cell death in the E. Coli model grown on the phantom. The results are promising and invite further experimental research.

  15. Magnetic Resonance Imaging of Neurosarcoidosis

    Directory of Open Access Journals (Sweden)

    Daniel T Ginat

    2011-01-01

    Full Text Available Neurosarcoidosis is an uncommon condition with protean manifestations. Magnetic resonance imaging (MRI is often used in the diagnostic evaluation and follow-up of patients with neurosarcoidosis. Therefore, familiarity with the variety of MRI appearances is important. In this pictorial essay, the range of possible patterns of involvement in neurosarcoidosis are depicted and discussed. These include intracranial and spine leptomeningeal involvement, cortical and cerebral white matter lesions, corpus callosum involvement, sellar and suprasellar involvement, periventricular involvement, cranial nerve involvement, cavernous sinus involvement, hydrocephalus, dural involvement, ischemic lesions, perivascular involvement, orbit lesions, osseous involvement, nerve root involvement, and spinal cord intramedullary involvement. Differential diagnoses for each pattern of involvement of neurosarcoidosis are also provided.

  16. Synovial pathology: Magnetic resonance study

    International Nuclear Information System (INIS)

    The synovial membrane lines the inner surface of the entire joint capsule of the so-called synovial, or diarthrosis, joints. It also constitutes the lining synovial bursa and tendon sheaths. It is lubricated at all these sites by the synovial fluid secreted by the membrane itself. The identification of this structure is bases on the correct knowledge of its anatomical locations. Synovial membrane pathology includes lesions produced by tumors, inflammation, degeneration and trauma. In this report, we classify them as benign (cysts, chondromatosis, pigmented villonodular synovitis, inflammatory synovitis and hemangioma) or malignant (synovial sarcoma and hemangiosarcoma). Magnetic resonance (MR) constitutes a useful and reliable method for diagnosis synovial lesions, providing a means of determining their origin and identifying distinctive features of some types. We present our experience in 12 cases of synovial pathology studied by MR over the past year, all of which were confirmed by histopathological study. 13 refs

  17. Fetal abdominal magnetic resonance imaging

    International Nuclear Information System (INIS)

    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. 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.

  19. The regional myocardial microvascular dysfunction differences in hypertrophic cardiomyopathy patients with or without left ventricular outflow tract obstruction: Assessment with first-pass perfusion imaging using 3.0-T cardiac magnetic resonance

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Hua-yan [Department of Radiology, National Key Laboratory of Biotherapy, West China Hospital, Sichuan University, 37# Guo Xue Xiang, Chengdu, Sichuan 610041 (China); Yang, Zhi-gang, E-mail: yangzg666@163.com [Department of Radiology, National Key Laboratory of Biotherapy, West China Hospital, Sichuan University, 37# Guo Xue Xiang, Chengdu, Sichuan 610041 (China); Sun, Jia-yu; Wen, Ling-yi; Zhang, Ge; Zhang, Shuai [Department of Radiology, National Key Laboratory of Biotherapy, West China Hospital, Sichuan University, 37# Guo Xue Xiang, Chengdu, Sichuan 610041 (China); Guo, Ying-kun [Department of Radiology, West China Second University Hospital, Sichuan University (China)

    2014-04-15

    Purpose: To assess regional myocardial microvascular dysfunction differences in hypertrophic cardiomyopathy (HCM) patients with or without left ventricular outflow tract obstruction using 3.0-T cardiac magnetic resonance (CMR) first-pass perfusion imaging. Materials and methods: Forty-two HCM patients, including 25 HCM patients with left ventricular outflow tract obstruction (HOCM), 17 HCM patients without left ventricular outflow tract obstruction (NOHCM), and 14 healthy subjects underwent CMR. The left ventricular (LV) function, left ventricular end-diastolic wall thickness (EDTH), and diameter of left ventricular outflow tract (LVOT) were measured and calculated. Based on the signal–time curve of the first-pass myocardium perfusion imaging, perfusion parameters including upslope, time to peak, and peak intensity, were assessed and compared by using one-way analysis of variance and independent t tests. Results: On the first-pass perfusion imaging, lower upslope and peak intensity and longer time to peak were found in HCM patients compared with normal subjects (all p < 0.05). In contrast to the NOHCM group, the average time to peak of the HOCM group was increased (13.30 ± 4.82 s vs 16.28 ± 4.90 s, p < 0.05), but first-pass perfusion upslope was reduced (4.96 ± 2.55 vs 2.58 ± 0.77, p < 0.05). According to the bull's-eye model, the HOCM group's average thickness of basal segments was thicker than the NOHCM group, especially the anteroseptal, inferolateral, and anterior wall values, with a corresponding lower first-pass perfusion upslope than the NOHCM group (all p < 0.05). A significant correlation was observed between first-pass perfusion upslope and LV EDTH (r = −0.551, p < 0.001) and LVOT diameter (r = 0.472, p < 0.001). Conclusions: The regional myocardial microvascular dysfunction differences in hypertrophic cardiomyopathy (HCM) patients with or without left ventricular outflow tract obstruction can be detected with first-pass perfusion CMR

  20. A Preliminary Study of the Cardiac Magnetic Resonance Multi-low-b DWI Technology%多个低b值DWI技术在心脏成像中的初步研究

    Institute of Scientific and Technical Information of China (English)

    刘明熙; 张挽时; 张子衡; 孟利民; 龚万沣; 刘洁; 方红; 王萍

    2016-01-01

    目的:初步研究多个低b值DWI技术在心脏检查中的成像技术和成像特点。方法对符合入组和排除条件的已签署知情同意书的30例健康志愿者行3.0T CMR Cine电影、T2WI和多b值DWI序列扫描,探讨此序列临床应用的可行性,统计分析心肌在各节段、不同供血区、年龄和性别中有无差异,并讨论行DWI序列扫描时,选择何种b值能够更好地反映心肌血流灌注情况。结果当b=20、60 s/mm2时,图像质量较好。健康志愿者各节段心肌ADC值不全相等(F=6.315,P<0.001)。左前降支供血区,右冠状动脉供血区和左旋支供血区ADC值有差异(F=27.804,P<0.001),分别为(0.01186±0.00422)mm2/s,(0.01032±0.00333)mm2/s和(0.00902±0.00248)mm2/s。从基底部到心尖部,心肌平均ADC值无差异。结论多个低b值DWI技术在CMR检查中具有较好的可行性和可重复性。健康志愿者各节段心肌ADC值存在节段性差异。当b=20,60 s/mm2(<100 s/mm2)时,图像质量较好,可能提示此DWI图像可更好地显示心肌血流灌注特点,为今后选择合理b值进行相关研究提供参考。%Objective To investigate the imaging technology and characteristics of cardiac magnetic resonance (CMR) multi-low-b DWI technology.Methods With a 3.0T magnetic resonance imaging (MRI) system, cardiovascular magnetic imaging, including MR Cine, T2WI and multi-low-b DWI technology, was performed in 30 healthy volunteers who had given written informed consent to investigate the clinical feasibility of multi-low-b DWI technology and to explore whether ADC values in different segmental myocardium, differentblood supply areas, different age-groups and gender were similar or not. A discussion was made on whichb value shouldbe selected tobetter relfect the perfusion of myocardium when using DWI technology to scan cardiac structure.Results The image quality of multi-low-b DWI technology wasbetter when theb

  1. Chemical Principles Revisited. Proton Magnetic Resonance Spectroscopy.

    Science.gov (United States)

    McQuarrie, Donald A.

    1988-01-01

    Discusses how to interpret nuclear magnetic resonance (NMR) spectra and how to use them to determine molecular structures. This discussion is limited to spectra that are a result of observation of only the protons in a molecule. This type is called proton magnetic resonance (PMR) spectra. (CW)

  2. Your Radiologist Explains Magnetic Resonance Angiography (MRA)

    Medline Plus

    Full Text Available ... produced 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 ...

  3. Contrast agents in magnetic resonance imaging

    International Nuclear Information System (INIS)

    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

  4. Pituitary tumors: Diagnosis by magnetic resonance imaging

    International Nuclear Information System (INIS)

    This paper presents a survey of the current status of the diagnosis of pituitary tumors by means of magnetic resonance imaging. It focuses on the clinical and practical aspects. The recommended procedure and the sequences and slice orientations for magnetic resonance imaging of the pituitary gland are presented, and the features that are essential for the diagnosis of pituitary tumors are discussed. (orig.)

  5. Magnetic resonance force microscopy: recent results

    International Nuclear Information System (INIS)

    Force detection of magnetic resonance has been demonstrated experimentally and used for imaging in EPR. This paper will review the basic principles of Magnetic Resonance Force Microscopy (MRFM) and will report some recent results in NMR imaging and the operation of a low-temperature MRFM. (author). 31 refs., 14 figs

  6. 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....

  7. 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....

  8. Functional Magnetic Resonance Imaging and Pediatric Anxiety

    Science.gov (United States)

    Pine, Daniel S.; Guyer, Amanda E.; Leibenluft, Ellen; Peterson, Bradley S.; Gerber, Andrew

    2008-01-01

    The use of functional magnetic resonance imaging in investigating pediatric anxiety disorders is studied. Functional magnetic resonance imaging can be utilized in demonstrating parallels between the neural architecture of difference in anxiety of humans and the neural architecture of attention-orienting behavior in nonhuman primates or rodents.…

  9. Nuclear magnetic resonance studies of erythrocyte membranes

    NARCIS (Netherlands)

    Chapman, D.; Kamat, V.B.; Gier, J. de; Penkett, S.A.

    1968-01-01

    The use of nuclear magnetic resonance spectroscopy for studying molecular interactions in biological membranes has been investigated using erythrocyte membrane fragments. Sonic dispersion of these fragments produces a sharp and well-defined high-resolution nuclear magnetic resonance spectrum. The sp

  10. Magnetic resonance imaging assessment of intraventricular dyssynchrony and delayed enhancement as predictors of response to cardiac resynchronization therapy in patients with heart failure of ischaemic and non-ischaemic etiologies

    International Nuclear Information System (INIS)

    Purpose: To assess the value of dyssynchrony and myocardial viability assessment by cardiac magnetic resonance (CMR) in prediction of response to cardiac resynchronization therapy (CRT) in patients with heart failure (HF) of both ischaemic and non-ischaemic etiologies. Materials and methods: Patients scheduled for CRT in NYHA class II–IV, left ventricular ejection fraction <35%, QRS ≥ 120 ms were included. Tagged cine and late gadolinium enhancement (LGE) images were performed. Dyssynchrony was assessed with inTag toolbox and LGE was quantified using cutoff value at half of maximal signal in the scar. Cardiopulmonary exercise test, echocardiography and blood testing for NT-proBNP levels were done at baseline and 6 months after CRT. Results: 52 patients (age 60.3 ± 13 years) were included. 26 patients (50%) met response criteria. The ischaemic etiology of HF was more frequent (69% vs. 31%, p = 0.002), the percent of LGE was higher (7.7% [0–13.5%] vs. 19.0% (0–31.9%], p = 0.013), regional vector of circumferential strain variance (RVV) was lower (0.27 ± 0.08 vs. 0.34 ± 0.09, p = 0.009) and uniformity of radial strain was higher (0.72 ± 0.25 vs. 0.56 ± 0.29, p = 0.046) in non-responders vs. responders. Multivariate logistic regression showed that RVV predicted response to CRT (HR 2.3, 95% CI 1.02–5.02, p = 0.0430) independently of LGE and the etiology of heart failure. In the subgroup of patients with ischaemic HF the extend of transmural scar within myocardium was higher in non-responders vs. responders (26.3% vs. 15.0% respectively, p = 0.01) and was a predictor of response to CRT in univariable analysis (HR 0.87, 95% CI 0.77–0.98, p = 0.025) providing the sensitivity of 76% and specificity of 75% at the cutoff point of 18% in the prediction of poor response to CRT. In patients with non-ischaemic HF QRS was wider (162 ms vs. 140 ms, p = 0.04), regional vector of strain variance (RVV) was higher (0.39 vs. 0.25, p = 0.002) and uniformity of radial

  11. Magnetic resonance imaging assessment of intraventricular dyssynchrony and delayed enhancement as predictors of response to cardiac resynchronization therapy in patients with heart failure of ischaemic and non-ischaemic etiologies

    Energy Technology Data Exchange (ETDEWEB)

    Petryka, Joanna, E-mail: joannapetryka@hotmail.com [Department of Coronary Artery Disease and Structural Heart Diseases, Institute of Cardiology, Warsaw (Poland); Cardiovascular Magnetic Resonance Unit, Institute of Cardiology, Warsaw (Poland); Miśko, Jolanta [Cardiovascular Magnetic Resonance Unit, Institute of Cardiology, Warsaw (Poland); Department of Radiology, Institute of Cardiology, Warsaw (Poland); Przybylski, Andrzej [Department of Arrhythmia, Institute of Cardiology, Warsaw (Poland); Śpiewak, Mateusz [Department of Coronary Artery Disease and Structural Heart Diseases, Institute of Cardiology, Warsaw (Poland); Cardiovascular Magnetic Resonance Unit, Institute of Cardiology, Warsaw (Poland); Małek, Łukasz A. [Cardiovascular Magnetic Resonance Unit, Institute of Cardiology, Warsaw (Poland); Department of Cardiology and Interventional Angiology, Institute of Cardiology, Warsaw (Poland); Werys, Konrad [Cardiovascular Magnetic Resonance Unit, Institute of Cardiology, Warsaw (Poland); Mazurkiewicz, Łukasz [Cardiovascular Magnetic Resonance Unit, Institute of Cardiology, Warsaw (Poland); Department of Cardiomyopathy, Institute of Cardiology, Warsaw (Poland); Gepner, Katarzyna [Department of Coronary Artery Disease, Institute of Cardiology, Warsaw (Poland); Croisille, Pierre [Creatis Laboratory, UMR CNRS 5515, INSERM, U1044, CHU Saint-Etienne, Universite de Lyon (France); Demkow, Marcin [Department of Coronary Artery Disease and Structural Heart Diseases, Institute of Cardiology, Warsaw (Poland); Rużyłło, Witold [Institute of Cardiology, Warsaw (Poland)

    2012-10-15

    Purpose: To assess the value of dyssynchrony and myocardial viability assessment by cardiac magnetic resonance (CMR) in prediction of response to cardiac resynchronization therapy (CRT) in patients with heart failure (HF) of both ischaemic and non-ischaemic etiologies. Materials and methods: Patients scheduled for CRT in NYHA class II–IV, left ventricular ejection fraction <35%, QRS ≥ 120 ms were included. Tagged cine and late gadolinium enhancement (LGE) images were performed. Dyssynchrony was assessed with inTag toolbox and LGE was quantified using cutoff value at half of maximal signal in the scar. Cardiopulmonary exercise test, echocardiography and blood testing for NT-proBNP levels were done at baseline and 6 months after CRT. Results: 52 patients (age 60.3 ± 13 years) were included. 26 patients (50%) met response criteria. The ischaemic etiology of HF was more frequent (69% vs. 31%, p = 0.002), the percent of LGE was higher (7.7% [0–13.5%] vs. 19.0% (0–31.9%], p = 0.013), regional vector of circumferential strain variance (RVV) was lower (0.27 ± 0.08 vs. 0.34 ± 0.09, p = 0.009) and uniformity of radial strain was higher (0.72 ± 0.25 vs. 0.56 ± 0.29, p = 0.046) in non-responders vs. responders. Multivariate logistic regression showed that RVV predicted response to CRT (HR 2.3, 95% CI 1.02–5.02, p = 0.0430) independently of LGE and the etiology of heart failure. In the subgroup of patients with ischaemic HF the extend of transmural scar within myocardium was higher in non-responders vs. responders (26.3% vs. 15.0% respectively, p = 0.01) and was a predictor of response to CRT in univariable analysis (HR 0.87, 95% CI 0.77–0.98, p = 0.025) providing the sensitivity of 76% and specificity of 75% at the cutoff point of 18% in the prediction of poor response to CRT. In patients with non-ischaemic HF QRS was wider (162 ms vs. 140 ms, p = 0.04), regional vector of strain variance (RVV) was higher (0.39 vs. 0.25, p = 0.002) and uniformity of radial

  12. Magnetic non-collinear neutron wave resonator

    CERN Document Server

    Khaidukov, Yu N

    2009-01-01

    The expression are received for amplitude of neutron reflection from layered magnetic non-collinear structure (neutron wave resonator (NWR)). It is showed the magnetic non-collinear NWR is characterized by the system of pairs of resonances for the spin flipped neutrons. The conditions are defined at which amplifying of spin-flipped neutron flux in wave resonator is multiple increased in comparison with amplifying of neutron absorption.

  13. Magnetic Resonance of the Knee

    International Nuclear Information System (INIS)

    Magnetic Resonance Imaging (MRI) has been applied to muscoloskeletal pathoanatomy and has proved to be useful in the detection and characterization of knees and 8 normal knees were examined. The images were obtained in the Diagnostic Centre RMRC of Naples on a 0.5 T superconductive magnetic system, using a surface coil and a spin-echo pulse sequence (SE 600/28 ms). The examined limb was immobilized and bent at 8-10 grade, extrarotated for the examination of the anterior cruciate ligament (ACL) only. Images were obtained on a 256x256 matrix and had a 2 or 4-mm thickness. MRI cleary showed all the anatomical structures. The anterior and posterior cruciate ligaments (ACL and PAL) and tha patellar ligament were shown by sagittal SE images through the intercondylar notch; the tibial and fibular collateral ligaments (TCL and FCL) were evaluated on coronal SE images; the articular capsula and menisci on axial transverse SE images. Objective criteria for ACL and PCL tears were: lack of continuity of the signal and change in signal intensity; in meniscal pathology, menisci with small linear regions of increased signal or with grossly truncated shape were interpreted as tears. Preliminary results of this study indicate that MRI together with clinical evaluation may be an useful non-invasive procedure in the assessment of acute injuries of the knee

  14. Stepped Impedance Resonators for High Field Magnetic Resonance Imaging

    OpenAIRE

    Akgun, Can E.; DelaBarre, Lance; Yoo, Hyoungsuk; Sohn, Sung-Min; Snyder, Carl J.; Adriany, Gregor; Ugurbil, Kamil; Gopinath, Anand; Vaughan, J. Thomas

    2014-01-01

    Multi-element volume radio-frequency (RF) coils are an integral aspect of the growing field of high field magnetic resonance imaging (MRI). In these systems, a popular volume coil of choice has become the transverse electromagnetic (TEM) multi-element transceiver coil consisting of microstrip resonators. In this paper, to further advance this design approach, a new microstrip resonator strategy in which the transmission line is segmented into alternating impedance sections referred to as step...

  15. Magnetic Microparticle Aggregation For Viscosity Determination By Magnetic Resonance

    OpenAIRE

    Hong, Rui; Cima, Michael J; Weissleder, Ralph; Josephson, Lee

    2008-01-01

    Micron-sized magnetic particles were induced to aggregate when placed in homogeneous magnetic fields, like those of magnetic resonance (MR) imagers and relaxometers, and then spontaneously returned to their dispersed state when removed from the field. Associated with the aggregation and dispersion of the magnetic particles were time dependent increases and decreases in the spin-spin relaxation time (T2) of the water. Magnetic nanoparticles, with far smaller magnetic moments per particle, did ...

  16. Nuclear Magnetic Resonance imaging; Resonance magnetique nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Thibierge, M.; Sevestre, L.; Slupecki, P. [Centre Hospitalier de Charleville-Mezieres, 08 (France)

    1998-06-01

    After many years of low profile business in the USA, MRI is back. Improvements are focused on high field magnets and on low field magnets. The former, are dedicated to high quality imaging. The new scanners are more and more efficient because of the spreading use of real time imaging. They can do now, procedures that just could not be imagined some years ago. Vascular imaging is done routinely. Abdominal imaging in apnea of EPI, perfusion and diffusion imaging, and, last not least, all the field of functional imaging are on the verge of coming out. The new magnets unveiled in 1997 are lighter, smaller, more, user friendly, less impressive for patients subject to claustrophobia. They also need less helium to operate and less space to be sited. The latter, are dedicated to interventional procedures. The new magnets are wide opened and a lot of companies show off. Though Picker unveiled a new light superconductive 0.5 Tesla magnet, it seems that this kind of machines are about to disappear. No significant progress was noticed in the field of dedicated MRI devices. Some features can be highlighted: the new Siemens short bore and its table integrates the Panoramic Array Coil Concept. It will allow simultaneous scanning with up to four coils; the excellent homogeneity of the new Picker magnet that will allow spectroscopy at 1 Tesla; the twin gradients of the Elscint Prisma that will open the field of microscopy MRI; the Philips `floppy gradients` that could speed up 4 or 6 times, the time needed for imaging; some new sequences sensitive to temperature are studied as WIP; a lot of work is achieved on 3 or 4 Tesla scanners etc. (author)

  17. Fusion of Color Doppler and Magnetic Resonance Images of the Heart

    OpenAIRE

    Wang, Chao; Chen, Ming; Zhao, Jiang-min; Liu, Yi

    2011-01-01

    This study was designed to establish and analyze color Doppler and magnetic resonance fusion images of the heart, an approach for simultaneous testing of cardiac pathological alterations, performance, and hemodynamics. Ten volunteers were tested in this study. The echocardiographic images were produced by Philips IE33 system and the magnetic resonance images were generated from Philips 3.0-T system. The fusion application was implemented on MATLAB platform utilizing image processing technolog...

  18. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... metal coils placed within blood vessels nearly all cardiac defibrillators and pacemakers You should tell the technologist ... Examples include but are not limited to: artificial heart valves implanted drug infusion ports artificial limbs or ...

  19. Magnetic resonance imaging in mucopolysaccharidosis

    Energy Technology Data Exchange (ETDEWEB)

    Nakajima, Seijun; Tanaka, Akemi; Kawawaki, Hisashi; Hattori, Hideji; Matsuoka, Osamu; Murata, Ryosuke; Isshiki, Gen; Inoue, Yuichi

    1988-11-01

    Magnetic resonance (MR) images in six patients with mucopolysaccharidosis (MPS), two with type I S, one with type II A, two with type III B, and one with type VI MPS, were reviewed and compared with reported pathological findings and with CT scans. We used a Picker International MR imager with a 0.5-tesla superconducting magnet. The pulse sequences involved the inversion recovery technique (TR, 2,100 msec ; TI, 600 msec ; TE, 40 msec) for the T/sub 1/-weighted images and spin echo technique (TR, 1,800 msec ; TE, 120 msec) for the T/sub 2/-weighted images. The TC scanner was a Somatom 2 or DR3. In the patients with type II A and type VI MPS, there were multi-focal lesions of various sizes that showed prolonged T/sub 1/ and T/sub 2/ in the white matter. These lesions, which were not detected by CT, seemed to be correlated with the pathological findings of cavitation and dilated periadventitial space with viscous fluid. In the patients with type II A and type III B MPS, the T/sub 2/-weighted images showed a reduced contrast between gray and white matters, which may be related to the deposition of glycolipids and mucopolysaccharides in the lysosomes of the neurons and astrocytes of the gray and white matters. These findings seemed to be correlated with the clinical finding of mental retardation. In the patient of type II A MPS, there were lesions that showed prolonged T/sub 2/ of the periventricular white matter, suggesting periventricular edema. But CT hardly detected these lesions. In the patients with type I S MPS, no abnormal findings were found in MR imaging. It was concluded that MR imaging was far more sensitive for the detection of MPS lesions than CT, and was a useful method for differential diagnosis in MPS.

  20. Magnetic resonance imaging in mucopolysaccharidosis

    International Nuclear Information System (INIS)

    Magnetic resonance (MR) images in six patients with mucopolysaccharidosis (MPS), two with type I S, one with type II A, two with type III B, and one with type VI MPS, were reviewed and compared with reported pathological findings and with CT scans. We used a Picker International MR imager with a 0.5-tesla superconducting magnet. The pulse sequences involved the inversion recovery technique (TR, 2,100 msec ; TI, 600 msec ; TE, 40 msec) for the T1-weighted images and spin echo technique (TR, 1,800 msec ; TE, 120 msec) for the T2-weighted images. The TC scanner was a Somatom 2 or DR3. In the patients with type II A and type VI MPS, there were multi-focal lesions of various sizes that showed prolonged T1 and T2 in the white matter. These lesions, which were not detected by CT, seemed to be correlated with the pathological findings of cavitation and dilated periadventitial space with viscous fluid. In the patients with type II A and type III B MPS, the T2-weighted images showed a reduced contrast between gray and white matters, which may be related to the deposition of glycolipids and mucopolysaccharides in the lysosomes of the neurons and astrocytes of the gray and white matters. These findings seemed to be correlated with the clinical finding of mental retardation. In the patient of type II A MPS, there were lesions that showed prolonged T2 of the periventricular white matter, suggesting periventricular edema. But CT hardly detected these lesions. In the patients with type I S MPS, no abnormal findings were found in MR imaging. It was concluded that MR imaging was far more sensitive for the detection of MPS lesions than CT, and was a useful method for differential diagnosis in MPS. (author)

  1. Interaction of magnetic resonators studied by the magnetic field enhancement

    OpenAIRE

    Yumin Hou

    2013-01-01

    It is the first time that the magnetic field enhancement (MFE) is used to study the interaction of magnetic resonators (MRs), which is more sensitive than previous parameters–shift and damping of resonance frequency. To avoid the coherence of lattice and the effect of Bloch wave, the interaction is simulated between two MRs with same primary phase when the distance is changed in the range of several resonance wavelengths, which is also compared with periodic structure. The calculated MFE osci...

  2. Functional magnetic resonance imaging by visual stimulation

    International Nuclear Information System (INIS)

    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)

  3. Presurgical functional magnetic resonance imaging

    International Nuclear Information System (INIS)

    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.)

  4. Magnetic resonance in multiple sclerosis

    International Nuclear Information System (INIS)

    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.)

  5. 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.

  6. Enhancement of artificial magnetism via resonant bianisotropy

    Science.gov (United States)

    Markovich, Dmitry; Baryshnikova, Kseniia; Shalin, Alexander; Samusev, Anton; Krasnok, Alexander; Belov, Pavel; Ginzburg, Pavel

    2016-03-01

    All-dielectric “magnetic light” nanophotonics based on high refractive index nanoparticles allows controlling magnetic component of light at nanoscale without having high dissipative losses. The artificial magnetic optical response of such nanoparticles originates from circular displacement currents excited inside those structures and strongly depends on geometry and dispersion of optical materials. Here an approach for enhancing of magnetic response via resonant bianisotropy effect is proposed and analyzed. The key mechanism of enhancement is based on electric-magnetic interaction between two electrically and magnetically resonant nanoparticles of all-dielectric dimer. It was shown that proper geometrical arrangement of the dimer in respect to the incident illumination direction allows flexible control over all vectorial components of the magnetic moment, tailoring the latter in the dynamical range of 100% and delivering enhancement up to 36% relative to performances of standalone spherical particles. The proposed approach provides pathways for designs of all-dielectric metamaterials and metasurfaces with strong magnetic responses.

  7. Late gadolinium enhancement in cardiovascular magnetic resonance in patients with hypertrophic cardiomyopathy complicated by life-threatening ventricular tachyarrhythmia

    NARCIS (Netherlands)

    Petkow-Dimitrow, Pawel; Klimeczek, Piotr; Vliegenthart, Rozemarijn; Pasowicz, Mieczyslaw; Miszalski-Jamka, Tomasz; Oudkerk, Matthijs; Podolec, Piotr; Dubiel, Jacek S.; Tracz, Wieslawa

    2009-01-01

    Background: Late gadolinium enhancement (LGE) on cardiac magnetic resonance imaging (CMR) has been shown to be associated with ventricular arrhythmias, however, its prognostic role in predicting sudden cardiac death has not yet been established. Aim: To explore a potential relationship between LGE v

  8. Quantification of aortic regurgitation by magnetic resonance velocity mapping

    DEFF Research Database (Denmark)

    Søndergaard, Lise; Lindvig, K; Hildebrandt, P;

    1993-01-01

    The use of magnetic resonance (MR) velocity mapping in the quantification of aortic valvular blood flow was examined in 10 patients with angiographically verified aortic regurgitation. MR velocity mapping succeeded in identifying and quantifying the regurgitation in all patients, and the...... calculated from MR imaging of the left ventricular end-diastolic and end-systolic volumes in eight patients (Y = 0.89 x X + 11, r = 0.97, p < 0.001). This finding was confirmed by a good agreement between the net cardiac output (L/min) quantified with MR velocity mapping and simultaneous 125I...

  9. 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

  10. International Society for Magnetic Resonance in Medicine

    Science.gov (United States)

    ... Join the ISMRM Journals History & Mission Central Office Society Award Winners Strategic Plan Policies Corporate Members Contact ... E-Library Virtual Meetings Connect With Us International Society for Magnetic Resonance in Medicine 2300 Clayton Road, ...

  11. Magnetic moment of the Roper resonance

    Energy Technology Data Exchange (ETDEWEB)

    Bauer, T. [Institut fuer Kernphysik, Johannes Gutenberg-Universitaet, D-55099 Mainz (Germany); Gegelia, J., E-mail: gegelia@kph.uni-mainz.de [Institut fuer Kernphysik, Johannes Gutenberg-Universitaet, D-55099 Mainz (Germany); Institut fuer Theoretische Physik II, Ruhr-Universitaet Bochum, 44780 Bochum (Germany); High Energy Physics Institute of TSU, 0186 Tbilisi, Georgia (United States); Scherer, S. [Institut fuer Kernphysik, Johannes Gutenberg-Universitaet, D-55099 Mainz (Germany)

    2012-08-29

    The magnetic moment of the Roper resonance is calculated in the framework of a low-energy effective field theory of the strong interactions. A systematic power-counting procedure is implemented by applying the complex-mass scheme.

  12. Magnetic resonance imaging for uterus leiomyoma diagnosis

    International Nuclear Information System (INIS)

    The possibilities of a new technique, magnetic resonance imaging (MRI) in leiomyoma diagnosis was studied. MRI has clear advantages to differentiate adenomyosis from lysosomes and to reveal combination of these processes, which can considerably influence the tactics of the treatment

  13. Your Radiologist Explains Magnetic Resonance Angiography (MRA)

    Medline Plus

    Full Text Available ... Pediatric Ultrasound Video: Angioplasty & vascular stenting Video: Arthrography Radiology and You About this Site RadiologyInfo.org is ... Explains Magnetic Resonance Angiography (MRA) Transcript Welcome to Radiology Info dot org Hello, I’m Dr. Elliot ...

  14. Chronic liver disease: evaluation by magnetic resonance

    International Nuclear Information System (INIS)

    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

  15. Your Radiologist Explains Magnetic Resonance Angiography (MRA)

    Medline Plus

    Full Text Available ... Angioplasty & vascular stenting Video: Arthrography Video: Contrast Material Radiology and You Take our survey About this Site ... Explains Magnetic Resonance Angiography (MRA) Transcript Welcome to Radiology Info dot org Hello, I’m Dr. Elliot ...

  16. Biliary Ascariasis on Magnetic Resonance Cholangiopancreatography

    OpenAIRE

    Hashmi, Mohammad A; Jevan K De

    2009-01-01

    A 17-year-old girl presented with features of biliary obstruction. Magnetic resonance cholangi-pancreatography revealed typical linear signals in common bile duct, which appears like Ascaris lumbricoides. The diagnosis was confirmed by endoscopic removal of the worm.

  17. Magnetic moment of the Roper resonance

    OpenAIRE

    Bauer, T.; Gegelia, J.; Scherer, S.

    2012-01-01

    The magnetic moment of the Roper resonance is calculated in the framework of a low-energy effective field theory of the strong interactions. A systematic power-counting procedure is implemented by applying the complex-mass scheme.

  18. Your Radiologist Explains Magnetic Resonance Angiography (MRA)

    Medline Plus

    Full Text Available ... this Site RadiologyInfo.org is produced by: Image/Video Gallery Your Radiologist Explains Magnetic Resonance Angiography (MRA) ... Recently posted: Focused Ultrasound for Uterine Fibroids Dementia Video: General Ultrasound Video: Pediatric Nuclear Medicine Radiology and ...

  19. Contribution to nuclear magnetic resonance imager using permanent magnets

    International Nuclear Information System (INIS)

    After some recalls of nuclear magnetic resonance, ways to get a stable and homogeneous magnetic field are studied with permanent magnets. Development of correction coils on integrated circuits has been particularly stressed. Gradient coil specific systems have been studied taking in account ferromagnetic material presence. Antenna system has been improved and possibility of image obtention with the prototype realized has been shown

  20. Advanced magnetic resonance spectroscopy techniques and applications

    OpenAIRE

    Cao, Peng; 曹鹏

    2013-01-01

    Magnetic resonance (MR) is a well-known non-invasive technique that provides spectra (by MR spectroscopy, MRS) and images (by magnetic resonance imaging, MRI) of the examined tissue with detailed metabolic, structural, and functional information. This doctoral work is focused on advanced methodologies and applications of MRS for probing cellular and molecular changes in vivo. A single-voxel diffusion-weighted (DW) MRS method was first developed for monitoring the size changes of intramyocellu...

  1. Concepts and indications of abdominal magnetic resonance

    International Nuclear Information System (INIS)

    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

  2. Magnetic Resonance Imaging with a Dielectric Lens

    OpenAIRE

    Vazquez, F.; Marrufo, O.; MARTIN,R; Rodriguez, A. O.

    2009-01-01

    Recently, metamaterials have been introduced to improve the signal-to-noise ratio (SNR) of magnetic resonance images with very promising results. However, the use polymers in the generation of high quality images in magnetic resonance imaging has not been fully been investigated. These investigations explored the use of a dielectric periodical array as a lens to improve the image SNR generated with single surface coils. Commercial polycarbonate glazing sheets were used together with a circula...

  3. Nuclear Magnetic Resonance Imaging: Current Capabilities

    OpenAIRE

    Davis, Peter L.; Crooks, Lawrence E.; Margulis, Alexander R.; Kaufman, Leon

    1982-01-01

    Nuclear magnetic resonance imaging can produce tomographic images of the body without ionizing radiation. Images of the head, chest, abdomen, pelvis and extremities have been obtained and normal structures and pathology have been identified. Soft tissue contrast with this method is superior to that with x-ray computerized tomography and its spatial resolution is approaching that of x-ray computerized tomography. In addition, nuclear magnetic resonance imaging enables us to image along the sag...

  4. Cardiovascular magnetic resonance of the right ventricle

    OpenAIRE

    Alpendurada, Francisco Diogo

    2013-01-01

    Introduction: Whilst most of the attention has been devoted to the left ventricle in cardiovascular disease, the right ventricle has been somewhat neglected. In the last decades, there has been a renewal of interest in the right ventricle, in part driven by advances in cardiovascular imaging. Methods: Cardiovascular magnetic resonance is arguably the best imaging modality for the study of the right ventricle. In this research thesis, cardiovascular magnetic resonance w...

  5. 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....

  6. Cat scratch disease: magnetic resonance imaging findings

    International Nuclear Information System (INIS)

    Cat scratch disease is an infectious lymphadenitis frequently occurring in children and adolescents. We present the magnetic resonance imaging findings of two patients with this disease. In both cases, lymphadenopathy was characterized by extensive stranding of the surrounding soft tissues, consistent with the inflammatory nature of this condition. Magnetic resonance imaging can be diagnostic and may obviate the need for invasive means of evaluation in patients suspected of having cat scratch disease. (orig.)

  7. Proton magnetic resonance spectroscopy in depression

    OpenAIRE

    Naren P Rao; Venkatasubramanian, Ganesan; Bangalore N Gangadhar

    2011-01-01

    Magnetic Resonance Spectroscopy (MRS) is a unique technique that can directly assess the concentration of various biochemical metabolites in the brain. Thus, it is used in the study of molecular pathophysiology of different neuropsychiatric disorders, such as, the major depressive disorder and has been an area of active research. We conducted a computer-based literature search using the Pubmed database with ‘magnetic resonance spectroscopy’, ‘MRS’, ‘depression’, and ‘major depressive disorder...

  8. Magnetic resonance urography in children

    International Nuclear Information System (INIS)

    The imaging methods play an important role in the diagnosing of the urinary tract diseases in children. The magnetic resonance urography (MRU) aids the morphological and functional assessment of the urinary tract as well as the increase of the accuracy of the diagnosing process. Objective: The aim of the study is to assess the capabilities of the MRU for the diagnosing of the urogenital tract in children. Material and methods: In 30 children, age between 20 days and 14 years, suspected for urinary tract pathology MRU is performed. The technique includes a native and contrast examination of the abdomen and the pelvis. The duration, depending on the pathology, is between 20 and 30 min. The axial scans and the 3-dimensional reconstructed images have been processed at different reconstruction angle. The findings have been compared to the other imaging methods applied and the postoperative results. Results: The MRU has allowed to diagnose different types of urogenital diseases in children - 3 with double pyelo-calyx system, 12 with obstructed mega ureter, 5 with obstruction of the pyelo-urinary segment, 5 with accompanying parenchyma anomalies, 6 with renal calculi, 5 with tumors, 1 with extrarenal tumor formation, 3 with bladder anomalies and 1 with kidney transplantation. Most of the children have combined pathology. Conclusions: MRU shows significant advantages in a number of pathological conditions as urinary tract obstruction, renal tumors, transplanted kidney and some congenital anomalies. The technique is safe, non-invasive and relatively fast for children examinations. These features of MRU presents a reason to assume that it will replace a number of conventional radiography techniques, giving more precise diagnostic information

  9. Complex Response Function of Magnetic Resonance Spectrometers

    OpenAIRE

    Annino, G.; Cassettari, M.; Fittipaldi, M.; M. Martinelli

    2002-01-01

    A vectorial analysis of magnetic resonance spectrometers, based on traveling wave resonators and including the reference arm and the automatic control of frequency, has been developed. The proposed model, valid also for stationary wave resonators, gives the response function of the spectrometer for any working condition, including scalar detectors with arbitrary response law and arbitrary excitation frequency. The purely dispersive and purely absorptive linear responses are discussed in detai...

  10. Enhancement of artificial magnetism via resonant bianisotropy

    CERN Document Server

    Markovich, Dmitry; Shalin, Alexander; Samusev, Anton; Krasnok, Alexander; Belov, Pavel; Ginzburg, Pavel

    2015-01-01

    All-dielectric "magnetic light" nanophotonics based on high refractive index nanoparticles allows controlling magnetic component of light at nanoscale without having high dissipative losses. The artificial magnetic optical response of such nanoparticles originates from circular displacement currents excited inside those structures and strongly depends on geometry and dispersion of optical materials. Here a new approach for increasing magnetic response via resonant bianisotropy effect is proposed and analyzed. The key mechanism of enhancement is based on electric-magnetic interaction between two electrically and magnetically resonant nanoparticles of all-dielectric dimer nanoantenna. It was shown that proper geometrical arrangement of the dimer in respect to the incident illumination direction allows flexible control over all vectorial components of magnetic polarizability, tailoring the later in the dynamical range of 100 % and enhancement up to 36 % relative to performances of standalone spherical particles....

  11. Nanoscale magnetic resonance imaging: Progress and challenges

    International Nuclear Information System (INIS)

    Magnetic resonance imaging (MRI), based on the sensitive detection of nuclear spins, enables three dimensional imaging without radiation damage. Conventional MRI techniques achieve spatial resolution that is at best a few micrometers due to sensitivity limitations of conventional inductive detection. The advent of ultrasensitive nanoscale magnetic sensing opens the possibility of extending MRI to the nanometer scale. If this can be pushed far enough, one can envision taking 3D images of individual biomolecules and, perhaps, even solving molecular structures of proteins. In this talk we will discuss issues related to nanoscale magnetic resonance imaging, especially its implementation using magnetic resonance force microscopy (MRFM). MRFM is based on the detection of ultrasmall (attonewton) magnetic forces. While 3D spatial resolution below 5 nm has been demonstrated, further progress depends on overcoming poorly understood near-surface force noise effects. We also consider the future possibility of using NV centers in diamond for detection of nanoMRI.

  12. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

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

  13. Diffuse infiltrative cardiac tuberculosis

    International Nuclear Information System (INIS)

    We present the cardiac magnetic resonance images of an unusual form of cardiac tuberculosis. Nodular masses in a sheet-like distribution were seen to infiltrate the outer myocardium and pericardium along most of the cardiac chambers. The lesions showed significant resolution on antitubercular therapy

  14. 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, ...

  15. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... of the head uses a powerful magnetic field, radio waves and a computer to produce detailed pictures ... medical conditions. MRI uses a powerful magnetic field, radio frequency pulses and a computer to produce detailed ...

  16. Coherence of magnetic resonators in a metamaterial

    Directory of Open Access Journals (Sweden)

    Yumin Hou

    2013-12-01

    Full Text Available The coherence of periodic magnetic resonators (MRs under oblique incidence is studied using simulations. The correlated phase of interaction including both the retardation effect and relative phase difference between two MRs is defined, and it plays a key role in the MR interaction. The correlated phase is anisotropic, as is the coherence condition. The coherence condition is the same as the Wood's anomaly and verified by the Fano resonance. This study shows that the applications of the Fano resonance of periodic MRs will become widespread owing to achieving the Fano resonance simply by tuning the incident angle.

  17. Cardiovascular magnetics resonance diagnosis of cystic tumor of the atrioventricular node

    Directory of Open Access Journals (Sweden)

    Wang Xuedong

    2009-04-01

    Full Text Available Abstract Late gadolinium enhanced (LGE cardiovascular magnetic resonance (CMR has proven to be the gold standard for viability assessment. LGE CMR is also useful for identifying the nature of cardiac masses or lesions. We report a case of a rare primary cystic tumor of the atrioventricular node, in which CMR proved to be valuable.

  18. Cardiovascular magnetics resonance diagnosis of cystic tumor of the atrioventricular node

    OpenAIRE

    Wang Xuedong; Starnes Vaughn; Tran Thao T; Getzen James; Ross Brian D

    2009-01-01

    Abstract Late gadolinium enhanced (LGE) cardiovascular magnetic resonance (CMR) has proven to be the gold standard for viability assessment. LGE CMR is also useful for identifying the nature of cardiac masses or lesions. We report a case of a rare primary cystic tumor of the atrioventricular node, in which CMR proved to be valuable.

  19. Association Diastolic Function by Echo and Infarct Size by Magnetic Resonance Imaging after STEMI

    DEFF Research Database (Denmark)

    Søholm, Helle; Lønborg, Jacob; Andersen, Mads J;

    2016-01-01

    echocardiography and myocardial salvage assessed with cardiac magnetic resonance (CMR) imaging in patients with ST-segment elevation MI (STEMI). DESIGN: In a prospective study, echocardiography and CMR were performed in STEMI-patients in the early post-MI phase assessing diastolic dysfunction according to E/A and...

  20. Low-temperature magnetic resonance force microscopy

    Science.gov (United States)

    Wago, Koichi

    Magnetic resonance force microscopy (MRFM) is a technique whose goal is to combine the three-dimensional, chemically specific imaging capability of magnetic resonance imaging with the atomic-scale spatial resolution of scanning force microscopy. MRFM relies on the detection of small oscillatory magnetic forces between spins in the sample and a magnetic tip, using a micromechanical cantilever. The force resolution is a key issue for successfully operating MRFM experiments. Operating at low temperature improves the force resolution because of the reduced thermal energy and increased mechanical Q of the cantilever. The spin polarization is also enhanced at low temperature, leading to the improved magnetic resonance sensitivity for ensemble spin samples. A low-temperature magnetic resonance force detection apparatus was built and used to demonstrate a force resolution of 8×10sp{-17}\\ N/sqrt{Hz} at 6 K with a commercial single-crystal silicon cantilever. Both nuclear magnetic resonance (NMR) and electron paramagnetic resonance (EPR) were detected in micron-size samples. Force-detection technique was also applied to a wide range of magnetic resonance measurements, including inversion recovery, nutation, and spin echoes. Force-detected EPR spectra of phosphorus-doped silicon revealed hyperfine splitting, illustrating the possibility of using the MRFM technique for spectroscopic purposes. An improved low-temperature magnetic resonance force microscope was also built, incorporating a magnetic tip mounted directly on the cantilever. This allows a much wider variety of samples to be investigated and greatly improves the convenience of the technique. Using the improved microscope, three-dimensional EPR imaging of diphenylpicrylhydrazil (DPPH) particles was accomplished by scanning the sample in two dimensions while stepping an external field. The EPR force map showed a broad response reflecting the size and shape of the sample, allowing a three-dimensional real

  1. Optimal Magnetic Sensor Vests for Cardiac Source Imaging

    OpenAIRE

    Stephan Lau; Bojana Petković; Jens Haueisen

    2016-01-01

    Magnetocardiography (MCG) non-invasively provides functional information about the heart. New room-temperature magnetic field sensors, specifically magnetoresistive and optically pumped magnetometers, have reached sensitivities in the ultra-low range of cardiac fields while allowing for free placement around the human torso. Our aim is to optimize positions and orientations of such magnetic sensors in a vest-like arrangement for robust reconstruction of the electric current distributions in t...

  2. Cardiac magnetic source imaging based on current multipole model

    Institute of Scientific and Technical Information of China (English)

    Tang Fa-Kuan; Wang Qian; Hua Ning; Lu Hong; Tang Xue-Zheng; Ma Ping

    2011-01-01

    It is widely accepted that the heart current source can be reduced into a current multipole. By adopting three linear inverse methods, the cardiac magnetic imaging is achieved in this article based on the current multipole model expanded to the first order terms. This magnetic imaging is realized in a reconstruction plane in the centre of human heart, where the current dipole array is employed to represent realistic cardiac current distribution. The current multipole as testing source generates magnetic fields in the measuring plane, serving as inputs of cardiac magnetic inverse problem. In the heart-torso model constructed by boundary element method, the current multipole magnetic field distribution is compared with that in the homogeneous infinite space, and also with the single current dipole magnetic field distribution.Then the minimum-norm least-squares (MNLS) method, the optimal weighted pseuDOInverse method (OWPIM), and the optimal constrained linear inverse method (OCLIM) are selected as the algorithms for inverse computation based on current multipole model innovatively, and the imaging effects of these three inverse methods are compared. Besides,two reconstructing parameters, residual and mean residual, are also discussed, and their trends under MNLS, OWPIM and OCLIM each as a function of SNR are obtained and compared.

  3. 170 Nanometer Nuclear Magnetic Resonance Imaging using Magnetic Resonance Force Microscopy

    CERN Document Server

    Thurber, K R; Smith, D D; Thurber, Kent R.; Harrell, Lee E.; Smith, Doran D.

    2003-01-01

    We demonstrate one-dimensional nuclear magnetic resonance imaging of the semiconductor GaAs with 170 nanometer slice separation and resolve two regions of reduced nuclear spin polarization density separated by only 500 nanometers. This is achieved by force detection of the magnetic resonance, Magnetic Resonance Force Microscopy (MRFM), in combination with optical pumping to increase the nuclear spin polarization. Optical pumping of the GaAs creates spin polarization up to 12 times larger than the thermal nuclear spin polarization at 5 K and 4 T. The experiment is sensitive to sample volumes containing $\\sim 4 \\times 10^{11}$ $^{71}$Ga$/\\sqrt{Hz}$. These results demonstrate the ability of force-detected magnetic resonance to apply magnetic resonance imaging to semiconductor devices and other nanostructures.

  4. Embroidered Coils for Magnetic Resonance Sensors

    Directory of Open Access Journals (Sweden)

    Michael I. Newton

    2013-04-01

    Full Text Available Magnetic resonance imaging is a widely used technique for medical and materials imaging. Even though the objects being imaged are often irregularly shaped, suitable coils permitting the measurement of the radio-frequency signal in these systems are usually made of solid copper. One problem often encountered is how to ensure the coils are both in close proximity and conformal to the object being imaged. Whilst embroidered conductive threads have previously been used as antennae in mobile telecommunications applications, they have not previously been reported for use within magnetic resonance. In this paper we show that an embroidered single loop coil can be used in a commercial unilateral nuclear magnetic resonance system as an alternative to a solid copper. Data is presented showing the determination of both longitudinal (T1 and effective transverse (T2eff relaxation times for a flat fabric coil and the same coil conformed to an 8 cm diameter cylinder. We thereby demonstrate the principles required for the wider use of fabric based conformal coils within nuclear magnetic resonance and magnetic resonance imaging.

  5. Planar Magnetic Metamaterial Slabs for Magnetic Resonance Imaging Applications

    Science.gov (United States)

    Li, Chun-Lai; Guo, Jie; Zhang, Peng; Yu, Quan-Qiang; Ma, Wei-Tao; Miao, Xi-Gen; Zhao, Zhi-Ya; Luan, Lin

    2014-07-01

    A type of planar magnetic metamaterial is proposed with a square winding microstructure as a superlens for magnetic resonance imaging (MRI) applications. A direct magnetic field mapping measurement demonstrates that the radio-frequency magnetic field passing through the superlens is increased by as high as 46.9% at the position of about 3 cm behind the superlens. The resonance frequency of the fabricated slabs is found to be in good agreement with the target frequency (63.6 MHz) for a 1.5T MRI system. MRI experiments with the magnetic superlens show that the intensity of the image and the SNR (signal-to-noise ratio) are both enhanced, implying promising MRI applications of our planar magnetic superlens.

  6. Generation of nuclear magnetic resonance images

    International Nuclear Information System (INIS)

    Two generation techniques of nuclear magnetic resonance images, the retro-projection and the direct transformation method are studied these techniques are based on the acquisition of NMR signals which phases and frequency components are codified in space by application of magnetic field gradients. The construction of magnet coils is discussed, in particular a suitable magnet geometry with polar pieces and air gap. The obtention of image contrast by T1 and T2 relaxation times reconstructed from generated signals using sequences such as spin-echo, inversion-recovery and stimulated echo, is discussed. The mathematical formalism of matrix solution for Bloch equations is also presented. (M.C.K.)

  7. Susceptibility effects in nuclear magnetic resonance imaging

    International Nuclear Information System (INIS)

    The properties of dephasing and the resulting relaxation of the magnetization are the basic principle on which all magnetic resonance imaging methods are based. The signal obtained from the gyrating spins is essentially determined by the properties of the considered tissue. Especially the susceptibility differences caused by magnetized materials (for example, deoxygenated blood, BOLD-effect) or magnetic nanoparticles are becoming more important for biomedical imaging. In the present work, the influence of such field inhomogeneities on the NMR-signal is analyzed. (orig.)

  8. Magnetic plasmonic Fano resonance at optical frequency.

    Science.gov (United States)

    Bao, Yanjun; Hu, Zhijian; Li, Ziwei; Zhu, Xing; Fang, Zheyu

    2015-05-13

    Plasmonic Fano resonances are typically understood and investigated assuming electrical mode hybridization. Here we demonstrate that a purely magnetic plasmon Fano resonance can be realized at optical frequency with Au split ring hexamer nanostructure excited by an azimuthally polarized incident light. Collective magnetic plasmon modes induced by the circular electric field within the hexamer and each of the split ring can be controlled and effectively hybridized by designing the size and orientation of each ring unit. With simulated results reproducing the experiment, our suggested configuration with narrow line-shape magnetic Fano resonance has significant potential applications in low-loss sensing and may serves as suitable elementary building blocks for optical metamaterials. PMID:25594885

  9. Magnetic resonance imaging of the body

    Energy Technology Data Exchange (ETDEWEB)

    Higgins, C.B.; Hricak, H.

    1987-01-01

    This text provides reference to magnetic resonance imaging (MRI) of the body. Beginning with explanatory chapters on the physics, instrumentation, and interpretation of MRI, it proceeds to the normal anatomy of the neck, thorax, abdomen, and pelvis. Other chapters cover magnetic resonance imaging of blood flow, the larynx, the lymph nodes, and the spine, as well as MRI in obstetrics. The text features detailed coverage of magnetic resonance imaging of numerous disorders and disease states, including neck disease, thoracic disease; breast disease; congenital and acquired heart disease; vascular disease; diseases of the liver, pancreas, and spleen; diseases of the kidney, adrenals, and retroperitoneum; diseases of the male and female pelvis; and musculoskeletal diseases. Chapters on the biological and environmental hazards of MRI, the current clinical status of MRI in comparison to other imaging modalities, and economic considerations are also included.

  10. Focal renal masses: magnetic resonance imaging

    International Nuclear Information System (INIS)

    Thirty patients with focal renal masses were evaluated on a .12-Tesla resistive magnetic resonance unit using partial saturation and spin echo pulse sequence. Fifteen patients had cystic lesions, nine patients had renal cell carcinoma, two had metastatic lesions, one had an angiomyolipoma, and three had focal bacterial infection. Renal cell carcinomas demonstrated areas of increased signal using a partial saturation sequence. Magnetic resonance imaging accurately detected perinephric extension and vascular invasion in all patients. Metastatic disease to the kidney was uniformly low in signal, in contrast to primary renal cell carcinoma; an angiomyolipoma demonstrated very high signal intensity. Two masses resulting from acute focal bacterial nephritis were uniformly low in signal. Magnetic resonance imaging appears to be an accurate way of detecting, identifying, and staging focal renal masses

  11. Tutte polynomial in functional magnetic resonance imaging

    Science.gov (United States)

    García-Castillón, Marlly V.

    2015-09-01

    Methods of graph theory are applied to the processing of functional magnetic resonance images. Specifically the Tutte polynomial is used to analyze such kind of images. Functional Magnetic Resonance Imaging provide us connectivity networks in the brain which are represented by graphs and the Tutte polynomial will be applied. The problem of computing the Tutte polynomial for a given graph is #P-hard even for planar graphs. For a practical application the maple packages "GraphTheory" and "SpecialGraphs" will be used. We will consider certain diagram which is depicting functional connectivity, specifically between frontal and posterior areas, in autism during an inferential text comprehension task. The Tutte polynomial for the resulting neural networks will be computed and some numerical invariants for such network will be obtained. Our results show that the Tutte polynomial is a powerful tool to analyze and characterize the networks obtained from functional magnetic resonance imaging.

  12. Fractionated magnetic-resonance elastography on the human heart

    International Nuclear Information System (INIS)

    Imaging techniques, including magnetic resonance imaging, belong to the most important tools in modern medical diagnostics. Another diagnostic aid is palpation, which is suitable for the qualitative characterization of pathological changes in organs near the surface. Magnetic resonance elastography (MRE) is a combination of these techniques. In principle, MRE uses motionsensitive MR-imaging to depict tissue deformation caused by externally induced shear waves. The type of deformation supply useful information about the elasticity of the tissue. Cardiac disorders are among the most common diseases. The goal of this study was to develop a method of applying in-vivo MRE to the human heart. The development of the mechanical stimulus, ultimately resulting in the introduction of an audio speaker as the source of vibration, provided the necessary means to introduce vibrations into inner organs. A crucial factor in applying MRE to the heart is the speed of the recording, which led to the development of ''fractional MRE''. The currently conventional fast heart imaging techniques were used as a starting point. The use of an unbalanced phase preparation gradient in the balanced steady-state imaging technique resulted in an improved phase-to-noise ratio. Along with the spoiled steady-state MRE imaging technique, initial MRE-studies on the human heart were performed. For the first time, externally induced mechanical vibrations were successfully introduced into the heart and were detected using fractional MRE with a high temporal resolution. The modulation of the shear wave amplitudes observed in the myocard of 6 healthy subjects correlated with the phases of the cardiac cycle. The techniques and methods developed here are a step toward routine clinical application of MRE of the heart and indicate high potential in the area of early diagnosis of cardiac disease. (orig.)

  13. Magnetic resonance signal moment determination using the Earth's magnetic field

    KAUST Repository

    Fridjonsson, Einar Orn

    2015-03-01

    We demonstrate a method to manipulate magnetic resonance data such that the moments of the signal spatial distribution are readily accessible. Usually, magnetic resonance imaging relies on data acquired in so-called k-space which is subsequently Fourier transformed to render an image. Here, via analysis of the complex signal in the vicinity of the centre of k-space we are able to access the first three moments of the signal spatial distribution, ultimately in multiple directions. This is demonstrated for biofouling of a reverse osmosis (RO) membrane module, rendering unique information and an early warning of the onset of fouling. The analysis is particularly applicable for the use of mobile magnetic resonance spectrometers; here we demonstrate it using an Earth\\'s magnetic field system.

  14. 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 risk, ... magnetic field is not harmful in itself, implanted medical devices that contain metal may malfunction or cause problems ...

  15. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... material called gadolinium, which is less likely to cause an allergic reaction than iodinated contrast material. Tell ... magnetic field is not harmful, but it may cause some medical devices to malfunction. Most orthopedic implants ...

  16. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... MRI uses a powerful magnetic field, radio frequency pulses and a computer to produce detailed pictures of ... sounds when the coils that generate the radiofrequency pulses are activated. Some centers provide earplugs, while others ...

  17. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... look like? The traditional MRI unit is a large cylinder-shaped tube surrounded by a circular magnet. ... still during imaging. A person who is very large may not fit into the opening of certain ...

  18. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... also screened for safety in the magnetic environment. Children will be given appropriately sized earplugs or headphones ... have special pediatric considerations. The teddy bear denotes child-specific content. Related Articles and Media MR Angiography ( ...

  19. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

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

  20. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... scanner. top of page How does the procedure work? Unlike conventional x-ray examinations and computed tomography ( ... also screened for safety in the magnetic environment. Children will be given appropriately sized earplugs or headphones ...

  1. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... x-ray contrast material, drugs, food, or the environment, or if you have asthma. The contrast material ... are also screened for safety in the magnetic environment. Children will be given appropriately sized earplugs or ...

  2. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

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

  3. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... pregnant. The magnetic field is not harmful, but it may cause some medical devices to malfunction. Most ... number of abrupt onset or long-standing symptoms. It can help diagnose conditions such as: brain tumors ...

  4. Magnetic Resonance Imaging (MRI) -- Head

    Medline Plus

    Full Text Available ... MRI centers allow a friend or parent to stay in the room as long as they are also screened for safety in the magnetic environment. Children will be given appropriately sized earplugs or headphones ...

  5. Magnetic resonance neurography. Imaging of peripheral nerves

    International Nuclear Information System (INIS)

    Magnetic resonance neurography (MRN) is a non-invasive technique using magnetic resonance imaging (MRI) in order to diagnose peripheral nerve pathologies and their underlying etiologies. MRN is already in clinical use and is now mostly used to delineate the anatomy of nerves and to establish the continuity or discontinuity of nerves in patients with traumatic nerve injuries, as well as to monitor processes of peripheral nerve degeneration and regeneration. This article reviews established and evolving novel MRN technologies with regard to their potential to meet the requirements for non-invasive imaging of peripheral nerves in clinical settings. (orig.)

  6. Magnetic Resonance Imaging with a Dielectric Lens

    CERN Document Server

    Vazquez, F; Martin, R; Rodriguez, A O

    2009-01-01

    Recently, metamaterials have been introduced to improve the signal-to-noise ratio (SNR) of magnetic resonance images with very promising results. However, the use polymers in the generation of high quality images in magnetic resonance imaging has not been fully been investigated. These investigations explored the use of a dielectric periodical array as a lens to improve the image SNR generated with single surface coils. Commercial polycarbonate glazing sheets were used together with a circular coil to generate phantom images at 3 Tesla on a clinical MR imager.

  7. The progress of coronary magnetic resonance imaging

    International Nuclear Information System (INIS)

    Coronary heart disease (CHD) is a kind of disease with high morbidity and mortality. The early detection and treatment has important significance to patient. With the features of noninvasive, no radiation, good soft tissue contrast and multi parameter, and displaying anatomy in arbitrary plane, magnetic resonance imaging (MRI) was gradually applied in coronary artery imaging. In this paper, the main sequence and scanning technology of coronary MRI were reviewed, factors that affecting the quality of coronary magnetic resonance imaging were summarized, and the main advantages and disadvantages were concluded. (authors)

  8. Nuclear magnetic resonance as a petrophysical measurement

    International Nuclear Information System (INIS)

    Nuclear magnetic resonance (NMR) of hydrogen nuclei in fluids which saturate porous rocks is important in oil exploration and production, since NMR logs can provide good estimates of permeability and fluid flow. This paper reviews developments which connect the NMR properties of rocks with petrophysical properties, and particularly those relating to fluid flow. The recent advances in the use of NMR in boreholes which have spurred these developments are also discussed. The relevance of other NMR measurements on geological samples, including magnetic resonance imaging, is briefly referred to. (author)

  9. Progress in nuclear magnetic resonance spectroscopy

    CERN Document Server

    Emsley, J W; Sutcliffe, L H

    2013-01-01

    Progress in Nuclear Magnetic Resonance Spectroscopy, Part 1 is a two-chapter text that reviews significant developments in nuclear magnetic resonance (NMR) applications.The first chapter discusses NMR studies of molecules physisorbed on homogeneous surfaces. This chapter also describes the phase changes in the adsorbed layer detected by following the variation in the NMR parameters. The second chapter examines the process to obtain a plotted, data reduced Fourier transform NMR spectrum. This chapter highlights the pitfalls that can cause a decrease in information content in a NMR spectrum. The

  10. Magnetic resonance neurography of the brachial plexus

    Directory of Open Access Journals (Sweden)

    Vaishali Upadhyaya

    2015-01-01

    Full Text Available Magnetic Resonance Imaging (MRI is being increasingly recognised all over the world as the imaging modality of choice for brachial plexus and peripheral nerve lesions. Recent refinements in MRI protocols have helped in imaging nerve tissue with greater clarity thereby helping in the identification, localisation and classification of nerve lesions with greater confidence than was possible till now. This article on Magnetic Resonance Neurography (MRN is based on the authors′ experience of imaging the brachial plexus and peripheral nerves using these protocols over the last several years.

  11. Complex Response Function of Magnetic Resonance Spectrometers

    CERN Document Server

    Annino, G; Fittipaldi, M; Martinelli, M

    2002-01-01

    A vectorial analysis of magnetic resonance spectrometers, based on traveling wave resonators and including the reference arm and the automatic control of frequency, has been developed. The proposed modelization, valid also for stationary wave resonators, gives the response function of the spectrometer for any working condition, including scalar detectors with arbitrary responsivity law and arbitrary excitation frequency. The purely dispersive and purely absorptive linear responses are discussed in detail for different scalar detectors. The developed approach allows to optimize the performances of the spectrometer and to obtain the intrinsic lineshape of the sample in a very broad range of working conditions. More complex setups can be modelized following the proposed scheme.

  12. Magnetic force microscopy using tip magnetization modulated by ferromagnetic resonance

    International Nuclear Information System (INIS)

    In magnetic force microscopy (MFM), the tip–sample distance should be reduced to analyze the microscopic magnetic domain structure with high spatial resolution. However, achieving a small tip–sample distance has been difficult because of superimposition of interaction forces such as van der Waals and electrostatic forces induced by the sample surface. In this study, we propose a new method of MFM using ferromagnetic resonance (FMR) to extract only the magnetic field near the sample surface. In this method, the magnetization of a magnetic cantilever is modulated by FMR to separate the magnetic field and topographic structure. We demonstrate the modulation of the magnetization of the cantilever and the identification of the polarities of a perpendicular magnetic medium. (paper)

  13. Magnetic force microscopy using tip magnetization modulated by ferromagnetic resonance

    Science.gov (United States)

    Arima, Eiji; Naitoh, Yoshitaka; Li, Yan Jun; Yoshimura, Satoru; Saito, Hitoshi; Nomura, Hikaru; Nakatani, Ryoichi; Sugawara, Yasuhiro

    2015-03-01

    In magnetic force microscopy (MFM), the tip-sample distance should be reduced to analyze the microscopic magnetic domain structure with high spatial resolution. However, achieving a small tip-sample distance has been difficult because of superimposition of interaction forces such as van der Waals and electrostatic forces induced by the sample surface. In this study, we propose a new method of MFM using ferromagnetic resonance (FMR) to extract only the magnetic field near the sample surface. In this method, the magnetization of a magnetic cantilever is modulated by FMR to separate the magnetic field and topographic structure. We demonstrate the modulation of the magnetization of the cantilever and the identification of the polarities of a perpendicular magnetic medium.

  14. Proton magnetic resonance spectroscopy and perfusion magnetic resonance imaging in the evaluation of musculoskeletal tumors

    International Nuclear Information System (INIS)

    Objective: To assess the role of proton magnetic resonance spectroscopy and dynamic contrast-enhanced magnetic resonance imaging in the differentiation between malignant and benign musculoskeletal tumors. Materials And Methods: Fifty-five patients with musculoskeletal tumors (27 malignant and 28 benign) were studied. The examinations were performed in a 1.5 T magnetic resonance scanner with standard protocol, and single voxel proton magnetic resonance spectroscopy with 135 msec echo time. The dynamic contrast study was performed using T1-weighted gradient-echo sequence after intravenous gadolinium injection. Time signal intensity curves and slope values were calculated. The statistical analysis was performed with the Levene's test, followed by a Student's t-test, besides the Pearson's chi-squared and Fischer's exact tests. Results: Proton magnetic resonance spectroscopy sensitivity, specificity and accuracy were, respectively, 87.5%, 92.3% and 90.9% (p < 0.0001). Statistically significant difference was observed in the slope (%/min) between benign (mean, 27.5%/min) and malignant (mean, 110.9%/min) lesions (p < 0.0001). Conclusion: The time-intensity curve and slope values using dynamic-enhanced perfusion magnetic resonance imaging in association with the presence of choline peak demonstrated by single voxel magnetic resonance spectroscopy study are useful in the differentiation between malignant and benign musculoskeletal tumors. (author)

  15. How Is Sudden Cardiac Arrest Diagnosed?

    Science.gov (United States)

    ... heart (a sign of CHD). MUGA Test or Cardiac MRI A MUGA (multiple gated acquisition) test shows how ... create pictures of many parts of your heart. Cardiac MRI (magnetic resonance imaging) is a safe procedure that ...

  16. Nuclear magnetic resonance of thermally oriented nuclei

    International Nuclear Information System (INIS)

    The more recent developments in the spectroscopy of Nuclear Magnetic Resonance on Oriented Nuclei (NMRON) are reviewed; both theoretical and experimental advances are summarised with applications to On-Line and Off-Line determination of magnetic dipole and electric quadrupole hyperfine parameters. Some emphasis is provided on solid state considerations with indications of where likely enhancements in technique will lead in conventional hyperfine studies. (orig.)

  17. Multi-dimensionally encoded magnetic resonance imaging

    OpenAIRE

    Lin, Fa-Hsuan

    2012-01-01

    Magnetic resonance imaging 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...

  18. Value of black blood T2* cardiovascular magnetic resonance

    Directory of Open Access Journals (Sweden)

    Carpenter John Paul

    2011-03-01

    Full Text Available Abstract Purpose To assess whether black blood T2* cardiovascular magnetic resonance is superior to conventional white blood imaging of cardiac iron in patients with thalassaemia major (TM. Materials and methods We performed both conventional white blood and black blood T2* CMR sequences in 100 TM patients to determine intra and inter-observer variability and presence of artefacts. In 23 patients, 2 separate studies of both techniques were performed to assess interstudy reproducibility. Results Cardiac T2* values ranged from 4.5 to 43.8 ms. The mean T2* values were not different between black blood and white blood acquisitions (20.5 vs 21.6 ms, p = 0.26. Compared with the conventional white blood diastolic acquisition, the coefficient of variance of the black blood CMR technique was superior for intra-observer reproducibility (1.47% vs 4.23%, p Conclusions Black blood T2* CMR has superior reproducibility and reduced imaging artefacts for the assessment of cardiac iron, in comparison with the conventional white blood technique, which make it the preferred technique for clinical practice.

  19. Magnetic Resonance Imaging of cardiomyopathy

    International Nuclear Information System (INIS)

    MRI has been proposed as a noninvasive method for evaluating patients with a variety of cardiomyopathies. Arrhythmogenic right ventricular dysplasia (ARVD) is defined as a primary disorder of the right ventricle characterized by partial or total replacement of muscle by adipose or fibrous tissue. Its diagnosis currently rests on techniques that accurately identify specific anatomic and functional abnormalities of the right ventricle. The aim of our study was to analyze the MRI features in 41 patients (age 19-64 years; 26 patients with ARVD, 7 patients with hypertrophic cardiomyopathy (HCM) and 8 patients with dilated cardiomyopathy (DCM)). They were investigated by spin-echo (SE) and gradient-echo (GE) Cine using a 0.5T unit Toshiba 50A with cardiac software. SE and Cine MRI allowed assessment of localization (hence type of HC) and extent of changes in visualized wall and ventricular dysfunction. In all patients with ARVD MRI SE-T1 W allowed localization of the abnormally bright signal intensity from the RV-free wall, apex and subtricuspid region, characteristic for the subcutenous fat. In 8 patients the structural changes were also present in left ventricular myocardium. MRI can be a useful method in supplying additional information to that obtained in 2D Echo by identifying the site, extent and type of cardiomyopathy. MRI is a very useful non-invasive method in diagnosis of ARVD. (author)

  20. Magnetic resonance imaging in sudden deafness

    International Nuclear Information System (INIS)

    The etiology of sudden deafness can remain undetermined despite extensive investigation. This study addresses the value of magnetic resonance imaging in the analysis of sudden deafness patients.Study Design: transversal cohort.Material And Method: In a prospective study, 49 patients attended at otolaryngology emergency room of Federal University of Sao Paulo - Escola Paulista de Medicina, from April 2001 to May 2003, were submitted to magnetic resonance imaging.Results: Magnetic Resonance abnormalities were seen in 23 (46.9%) patients and revealed two tumors suggestive of meningioma, three vestibular schwannomas, thirteen microangiopathic changes of the brain and five (21.7%) pathological conditions of the labyrinth.Conclusion: Sudden deafness should be approached as a symptom common to different diseases. The presence of cerebellopontine angle tumors in 10.2% of our cases, among other treatable causes, justifies the recommendation of gadolinium-enhanced magnetic resonance use, not only to study the auditory peripheral pathway, but to study the whole auditory pathway including the brain. (author)

  1. Numerical methods in electron magnetic resonance

    International Nuclear Information System (INIS)

    The focal point of the thesis is the development and use of numerical methods in the analysis, simulation and interpretation of Electron Magnetic Resonance experiments on free radicals in solids to uncover the structure, the dynamics and the environment of the system

  2. Sports Health Magnetic Resonance Imaging Challenge

    OpenAIRE

    Howell, Gary A.; Stadnick, Michael E.; Awh, Mark H.

    2010-01-01

    Injuries to the Lisfranc ligament complex are often suspected, particularly in the setting of midfoot pain without radiographic abnormality. Knowledge of the anatomy and magnetic resonance imaging findings of injuries to this region is helpful for the diagnosing and treating physicians.

  3. Sports Health Magnetic Resonance Imaging Challenge

    Science.gov (United States)

    Howell, Gary A.; Stadnick, Michael E.; Awh, Mark H.

    2010-01-01

    Injuries to the Lisfranc ligament complex are often suspected, particularly in the setting of midfoot pain without radiographic abnormality. Knowledge of the anatomy and magnetic resonance imaging findings of injuries to this region is helpful for the diagnosing and treating physicians. PMID:23015984

  4. Evaluation of nuclear magnetic resonance spectroscopy variability

    Energy Technology Data Exchange (ETDEWEB)

    Barreto, Felipe Rodrigues; Salmon, Carlos Ernesto Garrido, E-mail: garrido@ffclrp.usp.br [Universidade de Sao Paulo (FFCLRP/USP), Ribeirao Preto, SP (Brazil). Fac. de Filisofia, Ciencias e Letras; Otaduy, Maria Concepcion Garcia [Universidade de Sao Paulo (FAMUS/USP), Sao Paulo, SP (Brazil). Fac. de Medicina. Departamento de Radiologia

    2014-11-01

    Introduction: the intrinsically high sensitivity of Magnetic Resonance Spectroscopy (MRS) causes considerable variability in metabolite quantification. In this study, we evaluated the variability of MRS in two research centers using the same model of magnetic resonance image scanner. Methods: two metabolic phantoms were created to simulate magnetic resonance spectra from in vivo hippocampus. The phantoms were filled with the same basic solution containing the following metabolites: N-acetyl-aspartate, creatine, choline, glutamate, glutamine and inositol. Spectra were acquired over 15 months on 26 acquisition dates, resulting in a total of 130 spectra per center. Results: the phantoms did not undergo any physical changes during the 15-month period. Temporal analysis from both centers showed mean metabolic variations of 3.7% in acquisitions on the same day and of 8.7% over the 15-month period. Conclusion: The low deviations demonstrated here, combined with the high specificity of Magnetic Resonance Spectroscopy, confirm that it is feasible to use this technique in multicenter studies in neuroscience research. (author)

  5. Imaging Intelligence with Proton Magnetic Resonance Spectroscopy

    Science.gov (United States)

    Jung, Rex E.; Gasparovic, Charles; Chavez, Robert S.; Caprihan, Arvind; Barrow, Ranee; Yeo, Ronald A.

    2009-01-01

    Proton magnetic resonance spectroscopy ([to the first power]H-MRS) is a technique for the assay of brain neurochemistry "in vivo." N-acetylaspartate (NAA), the most prominent metabolite visible within the [to the first power]H-MRS spectrum, is found primarily within neurons. The current study was designed to further elucidate NAA-cognition…

  6. Magnetic resonance imaging in radiotherapy treatment planning

    NARCIS (Netherlands)

    Moerland, Marinus Adriaan

    2001-01-01

    From its inception in the early 1970's up to the present, magnetic resonance imaging (MRI) has evolved into a sophisticated technique, which has aroused considerable interest in var- ious subelds of medicine including radiotherapy. MRI is capable of imaging in any plane and does not use ionizing rad

  7. Evaluation of nuclear magnetic resonance spectroscopy variability

    International Nuclear Information System (INIS)

    Introduction: the intrinsically high sensitivity of Magnetic Resonance Spectroscopy (MRS) causes considerable variability in metabolite quantification. In this study, we evaluated the variability of MRS in two research centers using the same model of magnetic resonance image scanner. Methods: two metabolic phantoms were created to simulate magnetic resonance spectra from in vivo hippocampus. The phantoms were filled with the same basic solution containing the following metabolites: N-acetyl-aspartate, creatine, choline, glutamate, glutamine and inositol. Spectra were acquired over 15 months on 26 acquisition dates, resulting in a total of 130 spectra per center. Results: the phantoms did not undergo any physical changes during the 15-month period. Temporal analysis from both centers showed mean metabolic variations of 3.7% in acquisitions on the same day and of 8.7% over the 15-month period. Conclusion: The low deviations demonstrated here, combined with the high specificity of Magnetic Resonance Spectroscopy, confirm that it is feasible to use this technique in multicenter studies in neuroscience research. (author)

  8. Sensorineural hearing loss after magnetic resonance imaging

    DEFF Research Database (Denmark)

    Mollasadeghi, Abolfazl; Mehrparvar, Amir Houshang; Atighechi, Saeid;

    2013-01-01

    Magnetic resonance imaging (MRI) devices produce noise, which may affect patient's or operators' hearing. Some cases of hearing impairment after MRI procedure have been reported with different patterns (temporary or permanent, unilateral or bilateral, with or without other symptoms like tinnitus...

  9. Recent progress in magnetic resonance imaging

    International Nuclear Information System (INIS)

    Magnetic resonance imaging (MRI) has become a powerful tool in the life sciences and medical diagnosis, for which it was awarded the 2003 Nobel prize in physiology or medicine. The latest progress in MRI, including medical, brain-functional, in-vivo spectroscopic, and microscopic imaging are briefly reviewed

  10. 3D Reconstruction in Magnetic Resonance Imaging

    Czech Academy of Sciences Publication Activity Database

    Mikulka, J.; Bartušek, Karel

    2010-01-01

    Roč. 6, č. 7 (2010), s. 617-620. ISSN 1931-7360 R&D Projects: GA ČR GA102/09/0314 Institutional research plan: CEZ:AV0Z20650511 Keywords : reconstruction methods * magnetic resonance imaging Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  11. 3D Reconstruction in Magnetic Resonance Imaging

    Czech Academy of Sciences Publication Activity Database

    Mikulka, J.; Bartušek, Karel

    Cambridge : The Electromagnetics Academy, 2010, s. 1043-1046. ISBN 978-1-934142-14-1. [PIERS 2010 Cambridge. Cambridge (US), 05.07.2010-08.07.2010] R&D Projects: GA ČR GA102/09/0314 Institutional research plan: CEZ:AV0Z20650511 Keywords : 3D reconstruction * magnetic resonance imaging Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  12. Brain Magnetic Resonance Imaging in Tyrosinemia

    International Nuclear Information System (INIS)

    A 3.5-year-old girl with tyrosinemia is reported. A computed tomography scan of the abdomen revealed multiple hepatic nodules. Brain magnetic resonance imaging revealed bilateral high-signal changes confined to the globus pallidus on T2-weighted images. Globus pallidus lesions likely represented neuropathologic changes such as astocytosis, delayed myelination, and status spongiosus (myelin splitting and vacuolation)

  13. Cardiovascular magnetic resonance in systemic hypertension

    OpenAIRE

    Maceira Alicia M; Mohiaddin Raad H

    2012-01-01

    Abstract Systemic hypertension is a highly prevalent potentially modifiable cardiovascular risk factor. Imaging plays an important role in the diagnosis of underlying causes for hypertension, in assessing cardiovascular complications of hypertension, and in understanding the pathophysiology of the disease process. Cardiovascular magnetic resonance (CMR) provides accurate and reproducible measures of ventricular volumes, mass, function and haemodynamics as well as uniquely allowing tissue char...

  14. Magnetic Resonance Lithography with Nanometer Resolution

    Directory of Open Access Journals (Sweden)

    Fahad AlGhannam

    2016-04-01

    Full Text Available We propose an approach for super-resolution optical lithography which is based on the inverse of magnetic resonance imaging (MRI. The technique uses atomic coherence in an ensemble of spin systems whose final state population can be optically detected. In principle, our method is capable of producing arbitrary one and two dimensional high-resolution patterns with high contrast.

  15. Texture analysis methodologies for magnetic resonance imaging

    OpenAIRE

    Materka, Andrzej

    2004-01-01

    Methods for the analysis of digital-image texture are reviewed. The functions of MaZda, a computer program for quantitative texture analysis developed within the framework of the European COST (Cooperation in the Field of Scientific and Technical Research) B11 program, are introduced. Examples of texture analysis in magnetic resonance images are discussed.

  16. Numerical methods in electron magnetic resonance

    Energy Technology Data Exchange (ETDEWEB)

    Soernes, A.R

    1998-07-01

    The focal point of the thesis is the development and use of numerical methods in the analysis, simulation and interpretation of Electron Magnetic Resonance experiments on free radicals in solids to uncover the structure, the dynamics and the environment of the system.

  17. Brain Morphometry Using Anatomical Magnetic Resonance Imaging

    Science.gov (United States)

    Bansal, Ravi; Gerber, Andrew J.; Peterson, Bradley S.

    2008-01-01

    The efficacy of anatomical magnetic resonance imaging (MRI) in studying the morphological features of various regions of the brain is described, also providing the steps used in the processing and studying of the images. The ability to correlate these features with several clinical and psychological measures can help in using anatomical MRI to…

  18. Modelling Strategies for Functional Magnetic Resonance Imaging

    DEFF Research Database (Denmark)

    Madsen, Kristoffer Hougaard

    2009-01-01

    This thesis collects research done on several models for the analysis of functional magnetic resonance neuroimaging (fMRI) data. Several extensions for unsupervised factor analysis type decompositions including explicit delay modelling as well as handling of spatial and temporal smoothness and...

  19. Quantitative dosing by nuclear magnetic resonance

    International Nuclear Information System (INIS)

    The measurement of the absolute concentration of a heavy water reference containing approximately 99.8 per cent of D2O has been performed, by an original magnetic resonance method ('Adiabatic fast passage method') with a precision of 5.10-5 on the D2O concentration. (author)

  20. Biliary ascariasis on magnetic resonance cholangiopancreatography

    Directory of Open Access Journals (Sweden)

    Mohammad A Hashmi

    2009-01-01

    Full Text Available A 17-year-old girl presented with features of biliary obstruction. Magnetic resonance cholangi-pancreatography revealed typical linear signals in common bile duct, which appears like Ascaris lumbricoides. The diagnosis was confirmed by endoscopic removal of the worm.

  1. Magnetic resonance studies of solid polymers

    International Nuclear Information System (INIS)

    This paper is a review of the application of nuclear magnetic resonance (NMR) to solid polymers. In the first, theoretical part, the elements of the theory of NMR, which are necessary for the study of the properties of solid polymers are discussed: the moments method, nuclear relaxation and the distribution of correlation times. In the second part the experimental results are presented. (author)

  2. Magnetic resonance imaging in acute tendon ruptures

    Energy Technology Data Exchange (ETDEWEB)

    Daffner, R.H.; Lupetin, A.R.; Dash, N.; Riemer, B.L.

    1986-11-01

    The diagnosis of acute tendon ruptures of the extensor mechanism of the knee or the Achilles tendon of the ankle may usually be made by clinical means. Massive soft tissue swelling accompanying these injuries often obscures the findings, however. Magnetic resonance imaging (MRI) can rapidly demonstrate these tendon ruptures. Examples of the use of MRI for quadriceps tendon, and Achilles tendon rupture are presented.

  3. Magnetic resonance angiography in meningovascular syphilis

    International Nuclear Information System (INIS)

    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.)

  4. Magnetic resonance imaging in patients with cardiac pacemakers: In vitro- and vivo-evaluation at 0.5 Tesla; MRT bei Patienten mit Herzschrittmachern: In-vitro- und In-vivo-Evaluierung bei 0,5 Tesla

    Energy Technology Data Exchange (ETDEWEB)

    Sommer, T.; Block, W.; Schild, H. [Bonn Univ. (Germany). Radiologische Klinik; Lauck, G. [Innere Medizin, Kardiologie, Krankenhaus Marienhof, Koblenz (Germany); Schimpf, R. [Bonn Univ. (Germany). Medizinische Poliklinik; Smekal, A. v. [Muenchen Univ. (Germany). Radiologische Klinik und Poliklinik; Wolke, S. [Bonn Univ. (Germany). Inst. fuer Strahlen- und Kernphysik; Gieseke, J. [Philips Medizin Systeme Unternehmensbereich der Philips GmbH, Hamburg (Germany); Schneider, C.; Funke, H.D. [Bonn Univ. (Germany). Klinik fuer Herz- und Gefaesschirurgie

    1998-01-01

    Purpose: MRI is currently regarded as absolutely contraindicated in patients with implanted cardiac pacemakers. In this prospective study safety and feasibility of MRI in patients with new generation pacemakers (PM) was evaluated in vitro and in vivo. Results: In the static magnetic field all PM switched to the asynchronous mode due to activation of the Reed switch, resulting in continuous pacing at a fixed rate. In three PM models in vitro, however, after activation of the Reed switch, there was a software-induced switch back to the demand mode. In these PM inhibition and triggering were observed after starting the MRI scan due to influence of the pulsed magnetic fields. PM program changes, damage of PM components, dislocation/torque of the PM and rapid pacing of the PM were observed neither in vitro nor in vivo. Atrial and ventricular stimulation thresholds remained unchanged. Conclusion: MRI at 0.5 Tesla should not be regarded as absolutely contraindicated in patients with implanted new generation PM. However, knowledge of the behaviour of the specific PM model in static and pulsed magnetic fields is required, if necessary also changes of the PM program prior of the MRI exam, continuous ECG monitoring and cardiological stand-by. (orig.) [Deutsch] Ziel: MRT-Untersuchungen galten bisher bei Patienten mit implantierten Herzschrittmachern als absolut kontraindiziert. In dieser prospektiven Studie wurde erstmals die Durchfuehrbarkeit einer MRT-Untersuchung bei modernen Schrittmachern in vitro und in vivo evaluiert. Ergebnisse: Im statischen Magnetfeld kam es erwartungsgemaess zu einer Aktivierung des Reed-Kontraktes mit festfrequenter Stimulation im asynchronen Modus. Drei in vitro untersuchte Schrittmachermodelle schalteten im statischen Magnetfeld wieder zurueck in den Demand-Modus und zeigten unter dem Einfluss der gepulsten Magnetfelder intermittierende Inhibitionen und Triggerungen. Beeinflussung des Schrittmacherprogramms, Beschaedigungen von

  5. Interaction of magnetic resonators studied by the magnetic field enhancement

    Directory of Open Access Journals (Sweden)

    Yumin Hou

    2013-12-01

    Full Text Available It is the first time that the magnetic field enhancement (MFE is used to study the interaction of magnetic resonators (MRs, which is more sensitive than previous parameters–shift and damping of resonance frequency. To avoid the coherence of lattice and the effect of Bloch wave, the interaction is simulated between two MRs with same primary phase when the distance is changed in the range of several resonance wavelengths, which is also compared with periodic structure. The calculated MFE oscillating and decaying with distance with the period equal to resonance wavelength directly shows the retardation effect. Simulation also shows that the interaction at normal incidence is sensitive to the phase correlation which is related with retardation effect and is ultra-long-distance interaction when the two MRs are strongly localized. When the distance is very short, the amplitude of magnetic resonance is oppressed by the strong interaction and thus the MFE can be much lower than that of single MR. This study provides the design rules of metamaterials for engineering resonant properties of MRs.

  6. Sudden Cardiac Arrest

    Science.gov (United States)

    ... scan, or MUGA, which shows how well your heart is pumping blood. Magnetic resonance imaging (MRI) which gives doctors detailed pictures of your heart. How is SCA treated? Sudden cardiac arrest should ...

  7. The working principle of magnetic resonance therapy

    CERN Document Server

    Brizhik, Larissa; Fermi, Enrico

    2015-01-01

    In this paper we describe briefly the basic aspects of magnetic resonance therapy, registered as TMR therapy. Clinical studies have shown that application of this therapy significantly accelerates wound healing and, in particular, healing of the diabetic foot disease. To understand the working principle of this therapy, we analyze relevant to it biological effects produced by magnetic fields. Based on these data, we show that there is a hierarchy of the possible physical mechanisms, which can produce such effects. The mutual interplay between the mechanisms can lead to a synergetic outcome delayed in time, which can affect the physiological state of the organism. In particular, we show that soliton mediated charge transport during the redox processes in living organisms is sensitive to magnetic fields, so that such fields can facilitate redox processes in particular, and can stimulate the healing effect of the organism in general. This and other non-thermal resonant mechanisms of the biological effects of mag...

  8. Cardiovascular assessment of patients with Ullrich-Turner's Syndrome on Doppler echocardiography and magnetic resonance imaging

    Directory of Open Access Journals (Sweden)

    Castro Ana Valéria Barros de

    2002-01-01

    Full Text Available OBJECTIVE: To assess the cardiovascular features of Ullrich-Turner's syndrome using echocardiography and magnetic resonance imaging, and to correlate them with the phenotype and karyotype of the patients. The diagnostic concordance between the 2 methods was also assessed. METHODS: Fifteen patients with the syndrome were assessed by echocardiography and magnetic resonance imaging (cardiac chambers, valves, and aorta. Their ages ranged from 10 to 28 (mean of 16.7 years. The karyotype was analyzed in 11 or 25 metaphases of peripheral blood lymphocytes, or both. RESULTS: The most common phenotypic changes were short stature and spontaneous absence of puberal development (100%; 1 patient had a cardiac murmur. The karyotypes detected were as follows: 45,X (n=7, mosaics (n=5, and deletions (n=3. No echocardiographic changes were observed. In regard to magnetic resonance imaging, coarctation and dilation of the aorta were found in 1 patient, and isolated dilation of the aorta was found in 4 patients. CONCLUSION: The frequencies of coarctation and dilation of the aorta detected on magnetic resonance imaging were similar to those reported in the literature (5.5% to 20%, and 6.3% to 29%, respectively. This confirmed the adjuvant role of magnetic resonance imaging to Doppler echocardiography for diagnosing cardiovascular alterations in patients with Ullrich-Turner's syndrome.

  9. Ultra-fast magnetic resonance encephalography of physiological brain activity - Glymphatic pulsation mechanisms?

    Science.gov (United States)

    Kiviniemi, Vesa; Wang, Xindi; Korhonen, Vesa; Keinänen, Tuija; Tuovinen, Timo; Autio, Joonas; LeVan, Pierre; Keilholz, Shella; Zang, Yu-Feng; Hennig, Jürgen; Nedergaard, Maiken

    2016-06-01

    The theory on the glymphatic convection mechanism of cerebrospinal fluid holds that cardiac pulsations in part pump cerebrospinal fluid from the peri-arterial spaces through the extracellular tissue into the peri-venous spaces facilitated by aquaporin water channels. Since cardiac pulses cannot be the sole mechanism of glymphatic propulsion, we searched for additional cerebrospinal fluid pulsations in the human brain with ultra-fast magnetic resonance encephalography. We detected three types of physiological mechanisms affecting cerebral cerebrospinal fluid pulsations: cardiac, respiratory, and very low frequency pulsations. The cardiac pulsations induce a negative magnetic resonance encephalography signal change in peri-arterial regions that extends centrifugally and covers the brain in ≈1 Hz cycles. The respiratory ≈0.3 Hz pulsations are centripetal periodical pulses that occur dominantly in peri-venous areas. The third type of pulsation was very low frequency (VLF 0.001-0.023 Hz) and low frequency (LF 0.023-0.73 Hz) waves that both propagate with unique spatiotemporal patterns. Our findings using critically sampled magnetic resonance encephalography open a new view into cerebral fluid dynamics. Since glymphatic system failure may precede protein accumulations in diseases such as Alzheimer's dementia, this methodological advance offers a novel approach to image brain fluid dynamics that potentially can enable early detection and intervention in neurodegenerative diseases. PMID:26690495

  10. Pulse-driven magnetoimpedance sensor detection of cardiac magnetic activity.

    Directory of Open Access Journals (Sweden)

    Shinsuke Nakayama

    Full Text Available This study sought to establish a convenient method for detecting biomagnetic activity in the heart. Electrical activity of the heart simultaneously induces a magnetic field. Detection of this magnetic activity will enable non-contact, noninvasive evaluation to be made. We improved the sensitivity of a pulse-driven magnetoimpedance (PMI sensor, which is used as an electric compass in mobile phones and as a motion sensor of the operation handle in computer games, toward a pico-Tesla (pT level, and measured magnetic fields on the surface of the thoracic wall in humans. The changes in magnetic field detected by this sensor synchronized with the electric activity of the electrocardiogram (ECG. The shape of the magnetic wave was largely altered by shifting the sensor position within 20 mm in parallel and/or perpendicular to the thoracic wall. The magnetic activity was maximal in the 4th intercostals near the center of the sterna. Furthermore, averaging the magnetic activity at 15 mm in the distance between the thoracic wall and the sensor demonstrated magnetic waves mimicking the P wave and QRS complex. The present study shows the application of PMI sensor in detecting cardiac magnetic activity in several healthy subjects, and suggests future applications of this technology in medicine and biology.

  11. Magnetic resonance imaging by using nano-magnetic particles

    Energy Technology Data Exchange (ETDEWEB)

    Shokrollahi, H., E-mail: Shokrollahi@sutech.ac.ir [Electroceramics Group, Department of Materials Science and Engineering, Shiraz University of Technology, Shiraz (Iran, Islamic Republic of); Khorramdin, A. [Electroceramics Group, Department of Materials Science and Engineering, Shiraz University of Technology, Shiraz (Iran, Islamic Republic of); Isapour, Gh. [Department of Materials and Engineering, Hakim Sabzevari University (Iran, Islamic Republic of)

    2014-11-15

    Magnetism and magnetic materials play a major role in various biological applications, such as magnetic bioseparation, magnetic resonance imaging (MRI), hyperthermia treatment of cancer and drug delivery. Among these techniques, MRI is a powerful method not only for diagnostic radiology but also for therapeutic medicine that utilizes a magnetic field and radio waves. Recently, this technique has contributed greatly to the promotion of the human quality life. Thus, this paper presents a short review of the physical principles and recent advances of MRI, as well as providing a summary of the synthesis methods and properties of contrast agents, like different core materials and surfactants. - Highlights: • This paper studies the physics of MRI as a powerful diagnostic technique. • MRI uses the differentiation between healthy and pathological tissues. • The relaxation times can be shortened by the use of a magnetic contrast agent. • The magnetic nanoparticles act as contrast agents, helping to increase the resolution. • Different synthesis methods can influence the magnetic resonance behavior.

  12. Nuclear magnetic resonance (NMR): principles and applications

    International Nuclear Information System (INIS)

    The basis for the phenomenon of nuclear magnetic resonance (NMR) is the ability of certain nuclei possessing both intrinsic angular momentum or ''spin'' I and magnetic moment to absorb electromagnetic energy in the radio frequency range. In principle, there are approximately 200 nuclei which may be investigated using the NMR technique. The NMR spectrum consists of intensity peaks along an axis calibrated in terms of the steady magnetic field or the frequency of the radiofrequency electromagnetic radiation. Analysis of the number, spacing, position and intensity of the lines in an NMR spectrum consists of intensity peaks along an axis calibrated in terms of the steady magnetic field or the frequency of the radiofrequency electromagnetic radiation. Analysis of the number, spacing, position and intensity of the lines in an NMR spectrum provides a variety of qualitative and quantitative analytical applications. The most obvious applications consist of the measurements of nuclear properties, such as spin number and nuclear magnetic moment. In liquids, the fine structure of resonance spectra provides a tool for chemical identification and molecular structure analysis. Other applications include the measurements of self-diffusion coefficients, magnetic fields and field homogeneity, inter-nuclear distances, and, in some cases, the water content of biological materials. (author)

  13. Physics of Magnetic Resonance. Chapter 14

    International Nuclear Information System (INIS)

    The discovery of nuclear magnetic resonance (NMR), a property of nuclei in a magnetic field where they are able to absorb applied radiofrequency (RF) energy and subsequently release it at a specific frequency, goes back many decades to the early 1900s. Physicist Isidor I. Rabi, fascinated by the work of Otto Stern and Walther Gerlach which demonstrated that particles have intrinsic quantum properties, delved into the magnetic properties of nuclei, and in 1938 Rabi discovered the phenomenon of NMR. Several years later, in 1946, Felix Bloch and Edward Purcell refined the methods and successfully measured the NMR signal from liquids and solids. For their discoveries, Rabi received the Nobel Prize for physics in 1944 and Bloch and Purcell in 1952. While Rabi, Bloch, Purcell and other physicists working in this field had laid the foundations, a major discovery that transformed the NMR phenomenon for imaging was not made until 1973, when Paul Lauterbur developed a method for spatially encoding the NMR signal by utilizing linear magnetic field gradients. About the same time, Peter Mansfield had also discovered a means of determining the spatial structure of solids by introducing a linear gradient across the object. The idea of applying magnetic field gradients to induce spatially varying resonance frequencies to resolve the spatial distribution of magnetization was a major milestone and the beginning of magnetic resonance imaging (MRI). For their work, Lauterbur and Mansfield were awarded the Nobel Prize for medicine in 2003. Since its discovery, MRI has quickly become one of the most important medical imaging devices available to physicians today. Unlike other imaging modalities, such as X ray and computed tomography, MRI does not involve ionizing radiation. MRI also offers superior soft tissue contrast that is not possible with other imaging modalities. Furthermore, in MRI, the desired level of image contrast among different tissues can often be precisely controlled

  14. 21 CFR 892.1000 - Magnetic resonance diagnostic device.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Magnetic resonance diagnostic device. 892.1000... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1000 Magnetic resonance diagnostic device. (a) Identification. A magnetic resonance diagnostic device is intended for general diagnostic...

  15. Nuclear magnetic resonance imaging in patients with hypertrophic and dilated cardiomyopathy

    International Nuclear Information System (INIS)

    Patients with hypertrophic and dilated cardiomyopathy and normal subjects were investigated with nuclear magnetic resonance imaging. To evaluate the NMR scanner possibilities, the results were compared with the echocardiographic investigation of the same patients. The capabilities of NMR imaging to provide information about intracardiac anatomy are emphasized. This study is preceded by a description of the physical principles underlying the phenomenon of nuclear magnetic resonance and of the techniques used to obtain NMR images and a review of the clinical use of NMR imaging for cardiac diagnosis

  16. Soft x-ray resonant magnetic diffraction.

    OpenAIRE

    Wilkins, S. B.; Hatton, P. D.; Roper, M.D.; Prabhakaran, D.; Boothroyd, A. T.

    2003-01-01

    We have conducted the first soft x-ray diffraction experiments from a bulk single crystal, studying the bilayer manganite La22xSr12xMn2O7 with x 0:475 in which we were able to access the (002) Bragg reflection using soft x rays. The Bragg reflection displays a strong resonant enhancement at the LIII and LII manganese absorption edges. We demonstrate that the resonant enhancement of the magnetic diffraction of the (001) is extremely large, indeed so large that it exceeds that of t...

  17. Advances in magnetic and optical resonance

    CERN Document Server

    Warren, Warren S

    2013-01-01

    Advances in Magnetic and Optical Resonance contains three articles which review quite fundamentally different aspects of coherent spectroscopy. An enormous variety of effects can be observed when optical and spin resonances are coupled, usually by a combination of radio frequency and laser irradiation. The first article reviews these effects and pays particular attention to developing a theoretical framework which is as similar as possible for the optical and spin cases. Subsequent articles examine deuterium relaxation in molecular solids, and the spatiotemporal growth of multiple spin coheren

  18. Magnetic resonance imaging of valvular heart disease

    DEFF Research Database (Denmark)

    Søndergaard, Lise; Ståhlberg, F; Thomsen, C

    1999-01-01

    The optimum management of patients with valvular heart diseases requires accurate and reproducible assessment of the valvular lesion and its hemodynamic consequences. Magnetic resonance imaging (MRI) techniques, such as volume measurements, signal-void phenomena, and velocity mapping, can be used...... and predicting the optimal timing for valvular surgery. This paper reviews the validation of these MRI techniques in assessing valvular heart disease and discusses some typical pitfalls of the techniques, including suggestions for solutions.J. Magn. Reson. Imaging 1999;10:627-638....

  19. Method for Segmentation of the Endocardium and Epicardium of the Left Ventricle in Cardiac Magnetic Resonance Images%一种心脏核磁共振图像左室壁内、外膜分割方法

    Institute of Scientific and Technical Information of China (English)

    王元全; 贾云得

    2009-01-01

    为了充分利用心脏核磁共振图像(magnetic resonance image,简称 MRI)中关于左心室的解剖和功能信息,必须先分割左室壁内、外膜.提出-种基于Snake模型的左室壁内、外膜分割方法.首先提出了Snake模型的卷积虚拟静电场外力模型CONVEF(convolutional virtual electricfield),该外力场捕捉范围大、抗噪能力强,在C形凹陷区域等问题上性能突出,而且基于卷积运算,采用快速Fourier变换可以实时计算.就左室壁内膜的分割而言,考虑到左室壁的形状近似为圆形,引入基于圆形约束的能量项.对于左室壁外膜的分割,充分挖掘了左室壁内、外膜形状上的相似性和位置上的相关性,构造了形状相似性内能和-个新的边缘图,该边缘图用来计算新的外力场.基于所有这些策略并采用内膜的分割结果初始化,可以自动、准确地分割外膜.通过对-套活体心脏MR(magnetic resonance)图像进行分割并和手工分割结果和GGVF(generaJJized gadient vector flow)Snake模型的分割结果进行比较,结果表明该方法是有效的.

  20. Is there a place for cardiovascular magnetic resonance conditional devices in systemic inflammatory diseases?

    Science.gov (United States)

    Mavrogeni, Sophie I; Poulos, George; Sfikakis, Petros P; Kitas, George D; Kolovou, Genovefa; Theodorakis, George

    2016-06-01

    Rhythm disturbances and sudden cardiac death (SCD) are important manifestations of cardiac involvement in systemic inflammatory diseases (SID). The commonest events demanding the implantation of a device include ventricular tachycardia and atrioventricular block, mainly diagnosed in sarcoidosis, systemic lupus erythematosus and scleroderma. In SCD, cardiac magnetic resonance (CMR) identified areas of late gadolinium enhancement (LGE) in 71% and provided an arrhythmic substrate in 76%, while during the follow-up, the extent of LGE identified a subgroup at increased risk for future adverse events. CMR has been successfully used for detection of cardiac disease in SID, including myocarditis, coronary, microvascular and valvular disease. Additionally, SIDs have a higher probability to need MRI scanning of other organs, due to their systemic disease. These reasons support the necessity of an MRI conditional device in SIDs. A broad selection of devices, approved for the MRI environment under defined conditions allows the safe and accurate scanning of SID patients. PMID:26878099