A practical acceleration algorithm for real-time MRI is presented. Neither separate training scans nor embedded training samples are used. The Kalman filter based algorithm provides a fast and causal reconstruction of dynamic MRI acquisitions with arbitrary readout trajectories. The algorithm is tested against abrupt changes in the ...
PubMed Central
BackgroundCardiac dysfunction is associated with neuroanatomic and neuropsychological changes in aging adults with prevalent cardiovascular disease (CVD), theoretically because systemic hypoperfusion disrupts cerebral perfusion, contributing to subclinical brain injury. We hypothesized that cardiac function, as measured by cardiac ...
State-of-the-art cardiac MRI can perform real-time 2D scans without cardiac triggering during a single breath hold; however, real-time cardiac MRI in rats is difficult due to the high heart rate (330 bpm) and presence of respiratory motion. These challenges are overcome by using a dynamic ...
A lightweight 32-element MRI receiver-coil array was designed and built for cardiac imaging. It comprises an anterior array of 21 copper rings (75 mm diameter) and a posterior array of 11 rings (107 mm diameter) that are arranged in hexagonal lattices so as to decouple nearest neighbors, and curved around the left side of the torso. Imaging experiments on ...
Seismocardiography (SCG) is a methodology derived from the field of seismology to measure non-invasively compression waves generated by myocardial motion. The use of SCG is proposed here as method to monitor cardiac function during stress testing and magnetic resonance imaging (MRI). It is shown that recording of the seismocardiogram in subjects undergoing ...
PubMed
The purpose of this article is to provide a current review of the spectrum of multidetector CT (MDCT) and MRI findings for a variety of cardiac neoplasms. In the diagnosis of cardiac tumors, the use of MDCT and MRI can help differentiate benign from malignant masses. Especially, the use of MDCT is advantageous in ...
This article reviews the pathological classification of cardiac and pericardial neoplasms, the incidence of the various tumor types, and the role of CT and MRI, including their major differences and clinical impact on patient management.
Segmentation and Tracking of the Left Ventricle in Cardiac MRI by Leyla Imanirad A thesis submitted 2006 by Leyla Imanirad #12;Abstract Segmentation and Tracking of the Left Ventricle in Cardiac MRI Leyla. Perry Radau and Desmond Chung at Ontario Consortium for Cardiac Imaging (OCCI) for their ...
E-print Network
Endothelial Dysfunction; Myocardial Perfusion Abnormalities; Cardiac MRI Perfusion With Vasomotor Stress; Diabetes
ClinicalTrials.gov
First-pass cardiac perfusion MRI is a natural candidate for compressed sensing acceleration since its representation in the combined temporal Fourier and spatial domain is sparse and the required incoherence can be effectively accomplished by k-t random undersampling. However, the required number of samples in practice (three to five ...
When imaging the heart using MRI, an artefact-free electrocardiograph (ECG) signal is not only important for monitoring the patient's heart activity but also essential for cardiac gating to reduce noise in MR images induced by moving organs. The fundamental problem in conventional ECG is the distortion induced by electromagnetic interference. Here, we ...
Cardiac tumors are rare, and metastatic deposits are more common than primary cardiac tumors. We present cardiac magnetic resonance imaging (MRI) findings of a 50-year-old woman with invasive thymoma. Cardiac MRI revealed a heterogeneous, lobulated anterior mediastinal mass ...
Energy Citations Database
Time series of in-vivo magnetic resonance images exhibit high levels of temporal correlation. Higher temporal resolution reconstructions are obtained by acquiring data at a fraction of the Nyquist rate and resolving the resulting aliasing using the correlation information. The dynamic imaging experiment is modeled as a linear dynamical system. A Kalman filter based unaliasing reconstruction is ...
BACKGROUND--Magnetic resonance imaging (MRI) is a versatile technique for examination of the cardiovascular system but only recently has assessment of myocardial ischaemia in coronary artery disease (CAD) become possible, for example by demonstrating abnormalities of regional ventricular contraction during stress. Global ventricular function during stress was assessed by ...
to the effect of any type of acceleration on cardiac output; or ... cardiac output or which physiological changes could be caused by. Ox acceleration. ...
NASA Website
Compressed sensing (CS) is a data-reduction technique that has been applied to speed up the acquisition in MRI. However, the use of this technique in dynamic MR applications has been limited in terms of the maximum achievable reduction factor. In general, noise-like artefacts and bad temporal fidelity are visible in standard CS MRI reconstructions when ...
OBJECTIVE: MRI is a well-established modality for evaluating congenital and acquired cardiac diseases. This article reviews the latest pulse sequences used for cardiac MRI. In addition, the standard cardiac imaging planes and corresponding anatomy are described and illustrated. CONCLUSION: ...
Coronary magnetic resonance imaging (MRI) is a noninvasive imaging modality for diagnosis of coronary artery disease. One of the limitations of coronary MRI is its long acquisition time due to the need of imaging with high spatial resolution and constraints on respiratory and cardiac motions. Compressed sensing (CS) has been recently ...
Compared to traditional single-animal imaging methods, multiple-mouse MRI has been shown to dramatically improve imaging throughput and reduce the potentially prohibitive cost for instrument access. To date, up to a single radiofrequency coil has been dedicated to each animal being simultaneously scanned, thus limiting the sensitivity, flexibility, and ultimate throughput. The ...
... The magnetic field is produced by passing an electric current through wire coils in most MRI units. Other coils, located in the machine and in some cases, placed around the part ...
MedlinePLUS
An osteosarcoma of cardiac origin is extremely rare, and a comprehensive description of MR imaging (MRI) findings of cardiac osteosarcoma and its metastasis in the femur have not been reported in the literature. We present a case of cardiac osteosarcoma in a 47-year-old woman and its metastasis to the femur, ...
Neural signal changes associated with cardiac and respiratory measures vs boxcar analysis in functional magnetic resonance imaging (fMRI) ...
DTIC Science & Technology
... Neural Signal Changes Associated with Cardiac and Respiratory Measures vs Boxcar Analysis in Functional Magnetic Resonance Imaging (fMRI). ...
PURPOSE: To combine global cardiac function imaging with compressed sensing (CS) in order to reduce scan time and to validate this technique in normal mouse hearts and in a murine model of chronic myocardial infarction. MATERIALS AND METHODS: To determine the maximally achievable acceleration factor, fully acquired cine data, obtained in sham and ...
Recently new models of cardiac pacemakers have been commercialised. Some of these models have the particularity to be compatible with MRI (they are called MRI safe). The safety of the MRI for the patients implanted depends on the device it self and the lead(s). These review article focuses on the benefits and ...
... Title : Cardiac Changes in Miniature Swine Subjected to Acute Exercise, Exercise Conditioning, and Plus Gz Acceleration. ...
Magnetic resonance imaging (MRI) has become one of the state-of-the-art examinations for the primary diagnostics and follow-up of patients with congenital cardiac defects. The evaluation of the altered cardiovascular system, however, remains a diagnostic challenge. We present MRI findings in a boy with a complex congenital heart ...
PurposeTo develop and test a novel interactive real-time MRI environment that facilitates image-guided cardiovascular interventions.Materials and MethodsColor highlighting of device-mounted receiver coils, accelerated imaging of multiple slices, adaptive projection modes, live 3D renderings and other interactive features are utilized to enhance navigation ...
-oxide can be detected in vivo by cardiac MRI (Garot et al. 2003). Cancer, receptors and angiogenesis have
Acute Myocardial Infarction; Coronary Artery Disease; Myocardial Fibrosis; Gadolinium; Myocardial Edema
... magnetic resonance imaging (MRI), ultrasound, interventional radiology, ... Abstract: ... we evaluated cardiac function using a nuclear imaging ...
A 128-channel receive-only array coil is described and tested for cardiac imaging at 3T. The coil is closely contoured to the body with a �clam-shell� geometry with 68 posterior and 60 anterior elements, each 75 mm in diameter, and arranged in a continuous overlapped array of hexagonal symmetry to minimize nearest neighbor coupling. Signal-to-noise ratio (SNR) and noise ...
Functional information regarding cardiac performance, pressure gradients, and local flow derangement are available from blood acceleration fields. Thus, this study examines a 2D and 3D phase contrast sequence optimized to efficiently encode three-directional, time-resolved acceleration in vitro and in vivo. Stenosis phantom ...
Temporally Constrained Reconstruction of Dynamic Cardiac Perfusion MRI Ganesh Adluru,1�3 Suyash P:1027�1036, 2007. � 2007 Wiley-Liss, Inc. Key words: dynamic contrast-enhanced MR; cardiac perfusion- liasing by Fourier-encoding the overlaps using the tem- poral dimension (UNFOLD) method for cardiac cine
- and inter-modality registration problems. Application of slice-to-volume registration to cardiac MR dataMediated Spatiotemporal Registration of Cardiac DCE- MRI and Coronary MR Angiography Constantine registration of 3D angiography and 2D perfusion datasets. However, cardiac cycle phase mismatch between
Accelerated Three-Dimensional Upper Airway MRI Using Compressed Sensing Yoon-Chul Kim,* Shrikanth S). Compressed sensing MRI (CS-MRI) relies only on sparsity of the final reconstructed image in a transform speech production. CONCLUSIONS We have demonstrated the application of compressed sensing (CS) ...
Cardiac MR imaging is an effective method for noninvasive imaging of the heart. The technology has been limited in the past because of imaging difficulties associated with cardiac motion. In recent years, however, cardiac MR imaging has broadened its spectrum of applications in cardiovascular disease with impressive advances in spatial ...
Heart failure is a risk factor for Alzheimer's disease and cerebrovascular disease. In the absence of heart failure, it was hypothesized that left ventricular ejection fraction (LVEF), an indicator of cardiac dysfunction, would be associated with preclinical brain magnetic resonance imaging (MRI) and neuropsychological markers of ischemia and Alzheimer ...
Cardiac magnetic resonance imaging (MRI) for the diagnosis and management of many cardiac diseases has been established in clinical practice. It provides anatomic and functional information and is the most precise technique for quantification of ventricular volume, function and mass. Among cardiac ...
A study conducted by researchers at Wake Forest University Baptist Medical Center showed that using a cardiac MRI in the ED's observation unit enabled providers to manage most patients without admitting them, resulting in lower cost at the hospital of about $588 per patient. It also allowed diagnosis and prevention of all cardiac ...
The objective of this work is to design, examine and apply an eight channel transmit/receive coil array tailored for cardiac magnetic resonance imaging at 7.0T that provides image quality suitable for clinical use, patient comfort, and ease of use. The cardiac coil array was designed to consist of a planar posterior section and a modestly curved anterior ...
MRI has become an important tool to noninvasively assess global and regional cardiac function, infarct size, or myocardial blood flow in surgically or genetically modified mouse models of human heart disease. Constraints on scan time due to sensitivity to general anesthesia in hemodynamically compromised mice frequently limit the number of parameters ...
An optimized acceleration encoded phase contrast method termed "acceleration phase mapping" for the assessment of regional myocardial function is presented. Based on an efficient gradient waveform design using two-sided encoding for in vivo three-directional acceleration mapping, echo and repetition times TE = 12-14 ms and TR = 15-17 ...
segmentation of the myocardium in the dynamic contrast-enhanced (DCE) MRI images is an important step in the myocardium. A curvature penalty term is included in the evolution of the contours to ensure smoothness ventricle shape in order to segment the left ventricle myocardium from DCE cardiac MRI images. The algorithm
Magnetic resonance imaging (MRI) in patients with implanted cardiac prostheses and metallic cardiovascular electronic devices is sometimes a risky procedure. Thus MRI in these patients should be performed when it is the only examination able to help with the diagnosis. Moreover the diagnostic benefit must outweigh the risks. Coronary ...
Ebstein's anomaly (EA) is primarily diagnosed by echocardiography. The purpose of this study was to compare echocardiography and magnetic resonance imaging (MRI) in EA. Data from cardiac MRI and echocardiography were prospectively collected from 16 patients with EA. Imaging data also were compared with intraoperative findings. ...
A 78-year-old man with a history of pulmonary tuberculosis was referred for preoperative evaluation of cardiac function. Echocardiography and cardiac cine magnetic resonance imaging (MRI) indicated apical hypertrophic cardiomyopathy (HCM), a thickened visceral pericardium, and a large pericardial effusion. Cardiac ...
The rapid progress of MRI has been remarkable, and it is clear that it will become an important method for cardiac imaging. Its major advantages are the lack of ionizing radiation and the ability to obtain excellent global images of the cardiac walls and chambers without the need for contrast injection or cardiac ...
An automated myocardial segmentation in cardiac MRI R. El Berbari, I. Bloch, A. Redheuil, E to segment Cardiac Magnetic Resonance (CMR) images. A preprocessing step that consists in filtering the image the cavity and solve the problems due to the papillary muscles. Thereby the GVF snake algorithm is applied
ACCELERATED 3D MRI OF VOCAL TRACT SHAPING USING COMPRESSED SENSING AND PARALLEL IMAGING Yoon MRI: The application of compressed sensing for rapid MR imaging," Magn Reson Med, 2007; 58 of compressed sensing MRI with parallel imaging to 3D imaging of vocal tract shaping during sustained sound
BACKGROUND: Late gadolinium enhancement (LGE) of cardiac magnetic resonance imaging (MRI) represents myocardial fibrosis and may be related to the clinical outcome of various heart diseases. This study evaluated the relationship between LGE and cardiac events in hypertrophic cardiomyopathy (HCM) using a new scoring method. METHODS AND ...
... fractures. Four forms of diagnostic imaging (radiographs, bone scan, MRI and CT) are performed on each subject. The ...
The advent of high performance gradients and parallel imaging schemes has made real-time MRI a stable mode of scanning. Cardiac tagging techniques have been shown to give extremely precise and accurate estimates of the evaluation of myocardial function, W...
National Technical Information Service (NTIS)
... [1] ER McVeigh: MRI of myocardial function: motion ... echo segmented k -space imaging: an optimized hybrid sequence for ultra-fast cardiac imaging. ...
This thesis focuses on one aspect of cardiac magnetic resonance imaging (MRI) for noninvasive screening of ischemic heart disease: the identification and quantification of acutely infarcted myocardium using gadolineum-diethylene triamine pentaacetic acid ...
... I !Th:ij ll H l ;I l,;! Iti 'f THE EFFECT OF V&.RIOUS STRAINING MANEUVERS ON CARDIAC VOLUMES AT IG AND DURING +Gz ACCELERATION ...
which has occurred in patients with kidney failure getting. MRI contrast. ... in acute kidney failure. It has NEVER occurred in more ...
... In this study, we investigate the use of real-time Harmonic Phase (HARP) MRI for the quantitative, operator-independent detection of the onset of ...
... and the incidence of acute anaphylactoid reaction was 0.03 ... agents in a retrospective analysis of 78,383 ... MRI), cardiac CT and nuclear scintigraphic examinations ...
Center for Biologics Evaluation and Research (CBER)
Magnetic resonance imaging (MRI) will be performed pre-and post-flight as the most accurate means of measuring cardiac mass, including sufficient ...
Cardiac tamponade Chronic obstructive pulmonary disease (COPD) Coarctation of the aorta Constrictive pericarditis Cystic lung lesions Esophageal tumor Ischemic cardiomyopathy...
Science.gov Websites
... allergic to the dyes used in CT scanning. People who have severe kidney or liver ... rating was 1 star(s) Your rating was 2 star(s) Your rating was ...
Abstract: ... we evaluated cardiac function using a nuclear imaging technique in ... magnetic resonance imaging (MRI), ultrasound, interventional radiology, ...
Many cardiac diseases cause transmural differences in myofiber function. With the Magnetic Resonance Imaging Tagging technique a grid of magnetic tags was attached to the heart. Using a model of cardiac mechanics the motion of these tags was analyzed to d...
The registration and fusion of information from multiple cardiac image modalities such as magnetic resonance imaging he (MRI), X-ray computed tomography (CT), positron emission tomography (PET) and single photon emission computed tomography (SPECT) has be...
At the UMC Utrecht, The Netherlands, we have constructed a prototype MRI accelerator. The prototype is a modified 6 MV Elekta (Crawley, UK) accelerator next to a modified 1.5 T Philips Achieva (Best, The Netherlands) MRI system. From the initial design onwards, modifications to both systems were aimed to yield ...
NASA Astrophysics Data System (ADS)
OBJECTIVE: MRI plays an important role in the morphologic and functional evaluation of cardiovascular shunts. Good spatiotemporal resolution, inherent contrast resolution, wide FOV, and multiplanar imaging capabilities make MRI an ideal tool in the investigation of cardiovascular shunts. The velocity-encoded phase-contrast sequence is used in the ...
An MRI cardiac magnetic susceptometry (MRI-CS) technique for assessing cardiac tissue iron concentration based on phase mapping was developed. Normal control subjects (n=9) and thalassemia patients (n = 13) receiving long-term blood transfusion therapy underwent MRI-CS and ...
MR imaging of the human heart without explicit cardiac synchronization promises to extend the applicability of cardiac MR to a larger patient population and potentially expand its diagnostic capabilities. However, conventional non-gated imaging techniques typically suffer from low image quality or inadequate spatio-temporal resolution and fidelity. ...
PurposeTo compare standard of care nuclear SPECT imaging with cardiac magnetic resonance imaging (MRI) for emergency room (ER) patients with chest pain and intermediate probability for coronary artery disease.Materials and MethodsThirty-one patients with chest pain, negative electrocardiogram (ECG), and negative cardiac enzymes who ...
Establishing a clinical cardiovascular magnetic resonance imaging (MRI) program needs a dedicated technical surroundings as well as a specific and expert staff. These guidelines based either on proofs or on expert consensus are stated in order to help the physicians to reach or maintain the competence required for clinical use of cardiovascular MRI. After ...
Wegener�s granulomatosis (WG) is one of the most common small- and medium-sized necrotizing vasculitides that mainly affects the upper and lower respiratory tract and the kidneys. Cardiac manifestations in WG are relatively rare, and their role and place among different causes of mortality remain largely unknown. Substantially increased number of reports describing ...
Three subjects rested in the supine position, arose quickly, and ran for 1 min on a treadmill. Then they stood erect for 1 min and ran again. For the first 30 beats at the beginning of the run, their cardiac acceleration was greater after supine than afte...
The level of the sympathetic nervous system activity markedly increases during +Gz acceleration stress and this increase was implicated in the etiology of cardiac subendocardial hemorrhage associated with high sustained +Gz acceleration. The biochemical a...
renewed interest in the various issues related to human acceleration ..... tolerance to +Gz was reduced with gradual onset rates and cardiac arrhythmias ...
Dynamic magnetic resonance imaging (MRI) is a challenging problem because the MR data acquisition is often not fast enough to meet the combined spatial and temporal Nyquist sampling rate requirements. Current approaches to this problem include hardware-based acceleration of the acquisition, and model-based image reconstruction techniques. In this paper we ...
... under transverse accelerations were extrasystole, migration of cardiac rhythm from the sinus to the atrioventricular node, sinoatrial blockade ...
used in myocardial strain imaging. Incorporation of sensitivity encoding [5] and compressed sensing [6 the dynamic MRI images as + ))),((( 0 trBwrf jj , where )( 0 rf is a reference image, )( is the deformation estimate dynamic cardiac images and deformation maps between the images from under-sampled MRI data
, Syracuse, NY, United States Introduction Cardiac cine-MRI images are becoming more important in clinical diagnosis and treatment of heart disease. In order to quantitatively evaluate cardiac functional images] for real-time segmentation by approaching a N-D segmentation as an (N-1)-D minimization problem. A previous
2D short axis cardiac MRI images and to morph two image sets from a SOHO solar flare image sequence of techniques that deals with the metamorphosis of one image into another (also known as image interpolation applied our method to two different 2D short axis cardiac MRI images (2562 pixels) taken from a sequence
in the processing pathway between the acquisition of physiological data and its use in fMRI software for both on resting monkey cardiac and respiratory waveforms. PhysioNoise consistently identifies physiological simultaneous collection of functional brain images along with cardiac and respiratory signals, typically using
MRI offers an alternative to CT, and thus is central to an ALARA strategy. However, long exam times, limited magnet availability, and motion artifacts are barriers to expanded use of MRI. This article reviews developments in pediatric body MRI that might reduce these barriers: high field systems, acceleration, ...
Technical developments have considerably reduced the acquisition time and have improved the quality of magnetic resonance imaging. The recent recommendations of the European Society of Cardiology place MRI in the front line of investigations for the diagnosis and evaluation of congenital heart disease, cardiac tumours and pathology of the pericardium and ...
Ten cardiac and paracardiac masses were studied with magnetic resonance imaging (MRI) to evaluate the utility of this new method for determining the nature, location, and extent of such masses. The masses were intramural lesions (two cases), left atrial thrombus (one case), pericardial cysts (three cases), and mediastinal masses deforming and displacing ...
Iron-induced cardiac dysfunction is a leading cause of death in transfusion-dependent anemia. MRI relaxation rates R2(1/T2) and R2?(1?T2?) accurately predict liver iron concentration, but their ability to predict cardiac iron has been challenged by some investigators. Studies in animal ...
Cardiovascular magnetic resonance imaging (CVMRI) is of proven clinical value in the non-invasive imaging of cardiovascular diseases. CVMRI requires rapid image acquisition, but acquisition speed is fundamentally limited in conventional MRI. Parallel imaging provides a means for increasing acquisition speed and efficiency. However, signal-to-noise (SNR) limitations and the ...
Cardiac multidetector computed tomography (MDCT) for congenital heart disease is a useful, rapid, and noninvasive imaging technique bridging the gaps between echocardiography, cardiac catheterization, and cardiac MRI. Fast scan speed and greater anatomic coverage, combined with flexible ECG-synchronized scans and a ...
... are inserted into your body. MRI uses radio waves, magnets, and a computer to create pictures of your organs and tissues. Unlike computed tomography (to-MOG-ra-fee) scans (also called CT scans) and standard x rays, MRI doesn't use ionizing radiation or carry any risk of causing cancer. ...
Despite the excellent image-contrast capability of MRI and the ability to synchronize MRI with the murine cardiac cycle, this technique is underused for assessing mouse models of cardiovascular disease because of its perceived cost and complexity. This perception stems, in part, from complications associated with the placement and ...
Imaging of cardiac function and anatomy has advanced at an exponential rate over the past two decades. Our ability to quantitatively assess the degree of myocardial ischemia and accurately define the vascular anatomy using noninvasive techniques is greater than ever before. Current advances is cardiac imaging are allowing us to more safely assess patients ...
Functional magnetic resonance imaging (fMRI) relies on detecting small changes in signal during brain activities, in presence of various noise, including those caused by respiration and cardiac pulsation. In the resting state, there is no explicit task event except the baseline neuroactivities of awakeness and other unknowns. However, the resting state is ...
A 40-year-old man, who had been diagnosed with stage 2 pulmonary sarcoidosis, was referred to our hospital for further evaluation of dyspnea and cardiac function. The echocardiogram displayed thinning of the basal interventricular septum (IVS) and a reduced ejection fraction of 21%. Contrast-enhanced cardiac high resolution MRI (3 ...
, et al. Valve area and cardiac output in aortic stenosis: quantification by magnetic reso- nance far this calculation has been limited to 2D, time-resolved MRI data (1�3). Extension to 4D imaging resolution throughout the cardiac cycle. Although cardiac catheterization is considered to be a low
for monitoring calcium influx. A major disadvantage of manganese enhanced cardiac MRI is the toxicity of Mn2 (12 to the infused MnCl2 were detected except at the highest dose where there was a cardiac depressive effect that do not cause adverse cardiac effects. Magn Reson Med 54:196�200, 2005. Published 2005 ...
Resonance Imaging (MRI) [4]. Klein et al. [5] describe a system that unifies cardiac and respiratory gating. H., "Real-time system for respiratory-cardiac gating in positron tomography." IEEE Transactions Heidelberg 2006 List-Mode Affine Rebinning for Respiratory Motion Correction in PET Cardiac Imaging Adrian J
... superconducting magnetic coils contained in magnetic resonance imaging (MRI) equipment, magnetic levitation transportation, and particle accelerators.
In the UMC Utrecht a prototype MRI accelerator has been installed to investigate the feasibility of real-time, MRI guided radiotherapy. The system consists of a 6 MV Elekta (Crawley, UK) accelerator and a 1.5 T Philips (Best, The Netherlands) MRI system. The system is installed in a standard ...
We propose a new framework to propagate the labels in a heart atlas to the cardiac MRI images for ventricle segmentations based on image registrations. The method employs the anatomical information from the atlas as priors to constrain the initialisation between the atlas and the MRI images using region based registrations. After the ...
Recent developments in cardiac magnetic resonance imaging (MRI) have led to tremendous breakthroughs in the imaging of acute myocardial ischaemia and infarction. Hardware and acquisition sequences have improved image quality while simplifying cardiac examinations. Cine-MRI allows for accurate time-resolved imaging ...
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 ...
Both parallel MRI and compressed sensing (CS) are emerging techniques to accelerate conventional MRI by reducing the number of acquired data. The combination of parallel MRI and CS for further acceleration is of great interest. In this paper, we propose a novel method to combine sensitivity ...
Phase contrast MRI with multidirectional velocity encoding requires multiple acquisitions of the same k-space lines to encode the underlying velocities, which can considerably lengthen the total scan time. To reduce scan time, parallel imaging is often applied. In dynamic phase contrast MRI using standard generalized autocalibrating partially parallel ...
Recent theoretical advances in the field of compressive sampling-also referred to as compressed sensing (CS)-hold considerable promise for practical applications in MRI, but the fundamental condition of sparsity required in the CS framework is usually not fulfilled in MR images. However, in dynamic imaging, data sparsity can readily be introduced by applying the Fourier ...
This paper describes an acquisition and reconstruction strategy for cardiac cine MRI that does not require the use of electrocardiogram or breath holding. The method has similarities with self-gated techniques as information about cardiac and respiratory motion is derived from the imaging sequence itself; here, by acquiring the center ...
Abstract Objective: To demonstrate the visualization of penile abnormalities on fetal magnetic resonance imaging (MRI). Methods: This retrospective study included five fetuses (25+0 to 31+6 gestational weeks) with penile abnormalities, positively depicted on fetal MRI, using prenatal ultrasonography (US) as a standard of reference. On ...
. Fessler. An accelerated iterative reweighted least squares algorithm for compressed sensing MRI. In Proc, and recently entire sessions at MR conferences are devoted to this topic [77] [12]. Some compressed sensing. Santos, and J. M. Pauly. Com- pressed sensing MRI. IEEE Sig. Proc. Mag., 25(2):72�82, March 2008. [13] P
BackgroundTransfusional therapy for thalassemia major and sickle cell disease can lead to iron deposition and damage to the heart, liver, and endocrine organs. Iron causes the MRI parameters T1, T2, and T2* to shorten in these organs, which creates a potential mechanism for iron quantification. However, because of the danger and variability of cardiac ...
In vivo (molecular) imaging of the vessel wall of large arteries at subcellular resolution is crucial for unraveling vascular pathophysiology. We previously showed the applicability of two-photon laser scanning microscopy (TPLSM) in mounted arteries ex vivo. However, in vivo TPLSM has thus far suffered from in-frame and between-frame motion artifacts due to arterial movement with ...
Laser Doppler Anemometry (LDA) and accelerated fatigue testing were used in an attempt to assess the durability of two cardiac value bioprostheses. The LDA system was used to monitor the function of the cardiac valves over time. This was done through flow...
In a continuing investigation into cardiac control during acceleration, pharmacologic denervation of the heart was accomplished in squirrel monkeys with hexamethonium chloride (.005 mg/gm), and the animals dynamically stressed on an unique articulated cen...
OBJECTIVE: To review indications, contraindications, and risks of using magnetic resonance imaging (MRI) in order to help primary care physicians refer patients appropriately for MRI, screen for contraindications to using MRI, and educate patients about MRI. QUALITY OF EVIDENCE: Recommendations are based on classic ...
be useful for the detection of coronary artery disease (see Fig. 3). Myocardial Perfusion Imaging Figure 3 by a narrowing of the coronary arteries which deliver oxygen and nutrients to cardiac muscle (myocardium). IHD resonance imaging (MRI) of the coronary arteries and blood de- livery to the myocardium. Myocardial
Cardiac magnetic resonance imaging may be useful in the evaluation of peripartum cardiomyopathy, an inflammatory cardiomyopathy associated with pregnancy. Late gadolinium enhancement may be an indicator of ongoing inflammation and serve as a guide for endomyocardial biopsy for those patients not improving as expected with effective heart failure treatment. PMID:18684520
have any dental or orthodontic implants (fillings are O.K.)? Type have a Pacemaker? ___ ___ Do you have an implanted cardiac defibrillator? ___ ___ Do you have? _________________________________________________________________________________ ___ ___ Have you ever had eye surgery? ___ ___ Do you have lens implants? ___ ___ Do you wear dentures
An assessment of myocardial viability in a subject is performed by acquiring an MR image which distinguishes infarcted myocardium from normal myocardium. A contrast agent is used and after a waiting period, a cardiac-gated segmented inversion recovery gra...
The volumes of the intracranial space and the craniospinal system as a whole change during the cardiac cycle. These volume changes are caused by the pulsatile arterial inflow to the cranium, venous outflow from the cranium, and cerebrospinal fluid (CSF) f...
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...
Gao,G. Cockshott,P. Martin,T. Foster,J. Elliott,A. ...
Total spectral power, an index of overall HR variability, was calculated for the .... 2-dimensional ultrasound when assessing left ventricular (LV) function and ... cost alternative to MRI for evaluating cardiac function in patients. ...
BACKGROUND: -Myocardial hemorrhage after myocardial infarction (MI) usually goes undetected. We investigated the diagnostic accuracy of bright blood T(2)-weighted cardiac magnetic resonance imaging (MRI) for myocardial hemorrhage in experimental MI. METHODS AND RESULTS: -MI was created in swine by occluding the left anterior descending (n=10) or circumflex ...
Having a pacemaker has been seen an absolute contraindication to having an MRI scan. This has become increasingly difficult in clinical practice as insertion of pacemakers and implantable cardiac defibrillators is at an all time high. Here we outline a case where a 71-year-old male patient with a permanent pacemaker needed to have an ...
Congenital coronary artery fistula is a rare disease and MRI is a promising technique that may be useful to demonstrate the coronary artery tree. We report three patients who underwent cardiac MRI to investigate right coronary artery fistulae. On clinical examination, a continuous murmur was heard along the left sternal border, and ...
Although magnetic resonance imaging (MRI) is routinely used in clinical practice, long acquisition times limit its practical utility in many applications. To increase the data acquisition speed of MRI, parallel MRI (pMRI) techniques have recently been proposed. These techniques utilize multi-channel receiver arrays ...
MRI is known to be a superior modality for evaluating pericardial disease and masses because of its unmatched capacity for tissue characterization and high spatial resolution. New real-time sequences now complement the standard morphologic imaging of the pericardium with dynamic image acquisitions that also can provide hemodynamic information indicative of constriction. In the ...
Amyloidosis is a rare systemic disease. However, involvement of the heart is a common finding and is the most frequent cause of death in amyloidosis. We report the sonographic, scintigraphic, and MRI features of a pathologically proven case of cardiac amyloidosis. Delayed contrast-enhanced MR images, using an inversion recovery prepped gradient-echo ...
AIMS: Right ventricular (RV) systolic function is prognostically important, but its assessment by echocardiography remains challenging, in part because of the multitude of available measurement methods. The purpose of this prospective study was to rank these methods against the reference of RV ejection fraction (EF) as obtained in a broad clinical population by magnetic resonance imaging ...
For the last 15 years, Magnetic Resonance Imaging (MRI) has become a reference examination for cardiac morphology, function and perfusion in humans. Yet, due to the characteristics of cardiac MR images and to the great variability of the images among patients, the problem of heart cavities segmentation in MRI is ...
... and blackout 167 times; during 2557 +Gx runs, chest pain occurred 104 times, motion sickness 97 times, cardiac arrythmia and dyspnea 29 times ...
Heart rate fluctuations occur in the low frequency region (< 0.1 Hz) probed in functional magnetic resonance imaging (fMRI) studies of resting-state functional connectivity and most fMRI block paradigms, and may be related to low frequency blood-oxygenation-level-dependent (BOLD) signal fluctuations. To investigate this hypothesis, temporal correlations ...
Outpatient Clinic MICU/CCU 4401-4412 Acute Internal Medicine--B 4301-4319 Cath Lab -- Heart Station EP MRI (Level 4) Cardiac Rehab (Level 4) Cath Lab (Level 4) Center for Clinical and Translational Science (Level Services (Level 6) EP MRI Lab (Level 4) Heart Station (Level 4) Hope Chapel (Level 2) Huntsman Cancer
Magnetic resonance imaging (MRI) provides structural and functional cardiovascular information with excellent soft tissue contrast. Real-time MRI can guide transcatheter cardiovascular interventions in large animal models, and may prove superior to x-ray and adjunct modalities for peripheral vascular, structural heart and cardiac ...
BackgroundMagnetic Resonance Imaging (MRI) of patients with implanted cardiac devices is currently considered hazardous due to potential for electromagnetic interference to the patient and pacemaker system. With approximately 60 million MRI scans performed worldwide per year, an estimated majority of pacemaker patients may develop an ...
Managing patients with chest pain in the Emergency Department (ED) remains a challenge where advanced imaging technology may play a role. Detecting acute coronary syndrome in the emergency department with cardiac magnetic resonance imaging (MRI) was studied in 161 consecutive chest pain patients in a prospective observational study. Patients with ST ...
Partial anomalous pulmonary venous connection (PAPVC) is an extremely rare congenital condition where one or more of the pulmonary veins are connected to the venous circulation. Although initially suspected with unexplained right ventricular enlargement on transthoracic echocardiography (TTE), cardiac MRI is able to delineate the anatomical variant. We ...
Two patients with cardiac involvement of hydatid disease are presented: one with hydatid cyst of the interventricular septum and pulmonary arteries and the other with multiple pulmonary cysts associated with intracardiac and pericardial cysts. The ability of magnetic resonance imaging (MRI) to provide a global view of cardiac anatomy ...
This article describes a complex and not previously reported combination of congenital cardiac defects. Echocardiography showed dilation of right and left chambers, accompanied with patent ductus arteriosus, persistence of the left cranial vena cava, atrial septal defect (ASD), subaortic stenosis, and tricuspid dysplasia. The interatrial wall was examined and the diameter of ...
Congenital left ventricular diverticulum is a rare cardiac malformation characterized by a localized outpouching from the cardiac chamber. The patient is usually asymptomatic. However, complications like embolism, infective endocarditis, arrhythmia and, rarely, rupture can be the initial presentation. Diagnosis can be established by USG, echocardiography, ...
Anderson-Fabry disease is an X-linked lysosomal storage disorder resulting from a deficiency of the enzyme ?-galactosidase A (?-Gal A) and subsequent cellular storage of the enzyme's substrate globotriaosylceramide (Gb3) and related glycosphingolipids. We report a case of Anderson-Fabry disease with cardiac involvement evaluated with cardiovascular MRI. ...
A 14-year-old boy presented with an unusual bulging chest noted to be increasing slowly over the last few years. He had no other complaints. Cardiac echocardiography and cardiac magnetic resonance imaging (MRI) showed aneurysmal dilation of the ascending aorta with moderate aortic valve insufficiency and moderate pericardial effusion. ...
We compared the efficacy of echocardiography (ECHO) and magnetic resonance imaging (MRI) for evaluating intracardiac masses. Over an 8-yr period, 28 patients, 21 males, 7 females, 16 days-60 years of age (mean 25 years) with a suspected intracardiac mass on ECHO (transthoracic in all; transesophageal in 9) underwent an MRI examination. Five patients had a ...
Cardiac tumors are rare, and 3-quarters of these tumors are benign and nearly half of the benign tumors are myxomas. Metastases to the heart are more common than primary cardiac tumors. Cardiac tumors present obstructive, constitutional and embolic signs and symptoms. Echocardiograms, chest computed tomography (CT) and magnetic ...
ECG-gated cardiac MRI in the mouse is hindered by many technical difficulties in ECG signal recording inside high magnetic field scanners. The present study proposes a robust rectilinear method of acquiring cardiac and respiratory self-gated cine images in mouse hearts. In this approach, a motion-synchronization MR signal is collected ...
ABSTRACT: BACKGROUND: MANTICORE 101 - Breast (Multidisciplinary Approach to Novel Therapies in Cardiology Oncology Research) is a randomized trial to determine if conventional heart failure pharmacotherapy (angiotensin converting enzyme inhibitor or beta-blocker) can prevent trastuzumab-mediated left ventricular remodeling, measured with cardiac MRI, among ...
BackgroundMANTICORE 101 - Breast (Multidisciplinary Approach to Novel Therapies in Cardiology Oncology Research) is a randomized trial to determine if conventional heart failure pharmacotherapy (angiotensin converting enzyme inhibitor or beta-blocker) can prevent trastuzumab-mediated left ventricular remodeling, measured with cardiac MRI, among patients ...
Cardiac sarcoidosis is rare and subclinical involvement is four to five times more common than clinical involvement. Cardiac sarcoidosis is associated with a poor prognosis. ECG abnormalities are the most common presentation. However, as this case illustrates, it can also present as acute decompensated heart failure. Screening with ...
Ventricular geometry and fiber orientation may undergo global or local remodeling in cardiac disease. However, there are as yet no mathematical and computational methods for quantifying variation of geometry and fiber orientation or the nature of their remodeling in disease. Toward this goal, a landmark and image intensity-based large deformation diffeomorphic metric mapping ...
Electromagnetic waves can propagate through the body and are reflected at interfaces between materials with different dielectric properties. Therefore the reason for using ultrawideband (UWB) radar for probing the human body in the frequency range from 100 MHz up to 10 GHz is obvious and suggests an ability to monitor the motion of organs within the human body as well as obtaining images of ...
Congenital heart defect (CHD) is the most common birth defect and a frequent cause of death for children. Tetralogy of Fallot (ToF) is the most often occurring CHD which affects in particular the pulmonary valve and trunk. Emerging interventional methods enable percutaneous pulmonary valve implantation, which constitute an alternative to open heart surgery. While minimal invasive methods become ...
Multidetector CT (MDCT) with 64-slice capability continues to gain momentum for cardiovascular imaging. Beyond images of coronary arteries, it also provides reliable information on left ventricular structure and function, cardiac venous anatomy, the pulmonary venous system, and right ventricular function�all aspects important in the management of heart failure patients. ...
Imaging morphology and function of the right heart is of paramount importance in patients with adult congenital heart disease, since right ventricular dysfunction is associated with adverse cardiac events. Cardiac MRI has been shown to be a powerful tool for the non-invasive precise assessment of right ventricular and valvular ...
The major advances in cardiovascular care can be linked to the combined growth of advanced imaging modalities and the variety of treatment options available for patients with complex structural, acquired and congenital, valvular, myocardial and aortic diseases. Paralleling this growth are the number and spectrum of complications - such as device failures and infections - that these patients will ...
Sarcoidosis is a multi-system granulomatous disorder of unknown aetiology. Symptomatic cardiac involvement occurs in approximately 5% of patients. The prevalence of sarcoidosis in the Netherlands is unknown, but estimated to be approximately 20 per 100,000 population (3200 patients). We report on five patients who presented with different manifestations of ...
Cardiac MRI (CMR) provides a comprehensive evaluation of cardiac function and anatomy, as well as myocardial tissue characterization and perfusion. New data show the potential for CMR to analyze left ventricular diastolic function, coronary plaque and myocardial oxygen levels. A growing body of animal and clinical data on molecular ...
This book approaches adult cardiac disease from the correlative imaging perspective. It includes chest X-rays and angiographs, 2-dimensional echocardiograms with explanatory diagrams for clarity, plus details on digital radiology, nuclear medicine techniques, CT and MRI. It also covers the normal heart, valvular heart disease, myocardial disease, ...
BackgroundCardiac magnetic resonance (CMR) imaging has emerged as an important cardiac imaging technique for the evaluation of multiple cardiac pathologies.Objective/MethodThe goal of this review is to describe recent advances in techniques which have extended the potential applications of CMR. The focus will be on the clinical ...
A 56-year-old man was admitted complaining of throat discomfort and dyspnea. He was given a diagnosis of diffuse large B-cell lymphoma on the basis of findings from tumor biopsy specimens of his left pharynx. MRI tomograms and ultrasonic cardiograms revealed a right atrial tumor causing tricuspid stenosis. Although chemotherapy rendered the cardiac tumor ...
We report the case of a 67 year-old patient who presented with worsening chest pain and shortness of breath, four days post acute myocardial infarction. Contrast enhanced computed tomography of the chest ruled out a pulmonary embolus but revealed an unexpected small subepicardial aneurysm (SEA) in the lateral left ventricular wall which was confirmed on cardiac magnetic ...
The temporal evolution of heart failure and associated pulmonary congestion in rodent heart failure models has not yet been characterized simultaneously and noninvasively. In this study, MRI was used to assess the serial progression of left-ventricular dysfunction and lung congestion in mice following myocardial infarction (MI). Cardiac and lung (1) H ...
In perfusion MRI (p-MRI) exams, short-axis (SA) image sequences are captured at multiple slice levels along the long-axis of the heart during the transit of a vascular contrast agent (Gd-DTPA) through the cardiac chambers and muscle. Compensating cardio-thoracic motions is a requirement for enabling computer-aided quantitative ...
To perform cardiac imaging in mice without having to invest in expensive dedicated equipment, we adapted a clinical 1.5 Tesla (T) magnetic resonance imaging (MRI) scanner for use in a murine ischemia/reperfusion model. Phase-sensitive inversion recovery (PSIR) sequence facilitated the determination of infarct sizes in vivo by late gadolinium enhancement. ...
The methods currently utilized to track stem cells by cardiac MRI are affected by important limitations, and new solutions are needed. We tested human ferritin heavy chain (hFTH) as a reporter gene for in vivo tracking of stem cells by cardiac MRI. Swine cardiac stem/progenitor cells were ...
PURPOSE: To compare the accuracy of cardiac dual-source CT (DSCT) reconstructions obtained at 5% and 10% of the cardiac cycle and MRI for quantifying global left ventricular (LV) function and mass in heart transplant recipients. MATERIAL AND METHODS: We prospectively included 23 heart transplant recipients (21 male, mean age 60�11.7 ...
Patients with ?-thalassemia major at risk of cardiac iron overload have to be identified to undergo myocardial iron measurements by magnetic resonance imaging (MRI), especially, in areas and centers with restricted access to MRI. Measurements of heart iron, liver iron, and pancreatic exocrine function were performed in 44 patients by ...
This paper presents a novel, magnetic resonance imaging (MRI)-compatible, force sensor suitable for cardiac catheterization procedures. The miniature, fiber-optic sensor is integrated with the tip of a catheter to allow the detection of interaction forces with the cardiac walls. The optical fiber light intensity is modulated when a ...
Multipotent cardiac progenitor cells are found in the fetal and adult heart of many mammalian species including humans and form as intermediates during the differentiation of embryonic stem cells. Despite similar biological properties, the molecular identities of these different cardiac progenitor cell populations appear to be distinct. Elucidating the ...
High hepatic iron concentration (HIC) is associated with cardiac iron overload. However, simultaneous measurements of heart and liver iron often demonstrate no significant linear association. We postulated that slower rates of cardiac iron accumulation and clearance could reconcile these differences. To test this hypothesis, we examined the longitudinal ...
An integrated MRI-accelerator system provides MRI images before and during irradiation. Our purpose is to investigate the feasibility of treatment plan adaptation using solely MRI data, which lack density information. In this study we used CT data to quantify the tissue density effect. Treatment planning was performed for five prostate ...
BACKGROUND: Assessment of right ventricular (RV) volumes and function is important in patients after tetralogy of Fallot (TOF) repair. Currently, cardiac magnetic resonance imaging (MRI) is considered the clinical reference method for RV volume and function measurements. Three-dimensional (3D) knowledge-based reconstruction derived from two-dimensional ...
OBJECTIVE: To prospectively evaluate the accuracy of left and right ventricular function and myocardial mass measurements based on a dual-step, low radiation dose protocol with prospectively ECG-triggered 2nd generation dual-source CT (DSCT), using cardiac MRI (cMRI) as the reference standard. MATERIALS AND METHODS: Twenty patients ...
Several previous studies have demonstrated that administration of autologous bone marrow-derived mononuclear cells (BMMNCs) improve cardiac function in patients following acute myocardial infarction (AMI). However, optimum timing of administration has not been investigated in a clinical trial. The Cardiovascular Cell Therapy Research Network (CCTRN) was developed and funded by ...
Noninvasive measurement of the speed with which the cerebrospinal fluid (CSF) velocity wave travels through the spinal canal is of interest as a potential indicator of CSF system pressure and compliance, both of which may play a role in the development of craniospinal diseases. However, measurement of CSF velocity wave speed (VWS) has eluded researchers primarily due to either a lack of access to ...
Circumferential strain of the left ventricle reflects myocardial contractility and is considered a key index of cardiac function. It is also an important parameter in the quantitative evaluation of heart failure. Circumferential compression encoding, CIRCOME, is a novel method in cardiac MRI to evaluate this strain non-invasively and ...
Minimally invasive cardiac surgery requires arresting and emptying of the heart, which compromises visualization of the surgical field. In this feasibility study a novel surgical procedure is demonstrated in which real-time MRI is used to guide the placement of a prosthetic aortic valve in the beating heart via direct apical access in eight porcine hearts. ...
Purpose:Magnetic resonance imaging (MRI) is used to view soft tissues non-invasively, but the lung is challenging to image. We sought to evaluate MRI in assessing lung inflammation longitudinally in genetic mouse models of cystic fibrosis (CF).Material and Methods:Cftr+/+ (wild type) and Cftr?/? (CF) mice were ...
The aim of the study was to relate the extent of myocardial late gadolinium enhancement (LGE) in cardiac MRI to intraoperative graft flow in patients undergoing coronary artery bypass graft (CABG) surgery. Thirty-three CAD patients underwent LGE MRI before surgery using an inversion-recovery GRE sequence (turboFLASH). Intraoperative ...
The evaluation of plaque characteritics as well as the degree of luminal narrowing is important in the management of carotid stenosis. Several reports have shown that intraplaque hemorrhage (IPH), which plays a pivotal role in plaque vulnerability, emits high signal intensity on T1-weighted images of high-resolution black-blood (BB) MRIs. When an MRI is used to screen for ...
The objective of this article is to clarify the advantages and limits of echocardiography, MRI, and CT for the determination of left ventricular (LV) function, emphasising the importance of evaluating global ventricular function. MRI is the reference technique, owing to its precision, reproducibility, and innocuous nature. However, echography is performed ...
Accelerated Proton Echo Planar Spectroscopic Imaging (PEPSI) Using GRAPPA with a 32-Channel Phased the encod- ing time of MR spectroscopic imaging (MRSI). Here we inves- tigate up to 5-fold acceleration of 2 words: proton echo planar spectroscopic imaging; PEPSI; MR spectroscopic imaging; parallel MRI; 32
Cardiac resynchronization therapy is a high cost therapeutic option with proven efficacy on improving symptoms of ventricular failure and for reducing both hospitalization and mortality. However, a significant number of patients do not respond to cardiac resynchronization therapy that is due to various reasons. Identification of the optimal pacing site is ...
The purpose of this study is to establish a method of measuring precisely the seismocardiogram (SCG) of a patient who lying in an open magnetic resonance imaging (openMRI) machine for myocardial ischemia monitoring during surgery. Vibration isolation was examined by analyzing the gantry vibration during MRI scanning and the SCG of a healthy volunteer. The ...
The blood-oxygen level dependent (BOLD) signals measured by functional magnetic resonance imaging (fMRI) are contaminated with noise from various physiological processes, such as spontaneous low-frequency oscillations (LFOs), respiration, and cardiac pulsation. These processes are coupled to the BOLD signal by different mechanisms, and represent variations ...
