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2014
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2013, 2013 8th International Symposium on Image and Signal Processing and Analysis (ISPA)
2014, 2014 IEEE International Ultrasonics Symposium
2008, Journal of Magnetic Resonance Imaging
2005, Investigative Radiology
2011
Background: The purpose of this work is to analyze differences in left ventricular torsion between volunteers and patients with non-ischemic cardiomyopathy based on tissue phase mapping (TPM) cardiovascular magnetic resonance (CMR). Methods: TPM was performed on 27 patients with non-ischemic cardiomyopathy and 14 normal volunteers. Patients underwent a standard CMR including late gadolinium enhancement (LGE) for the assessment of myocardial scar and ECG-gated cine CMR for global cardiac function. TPM was acquired in short-axis orientation at base, mid, and apex for all subjects. After evaluation by experienced observers, the patients were divided in subgroups according to the presence or absence of LGE (LGE+/LGE-), local wall motion abnormalities (WM+/WM-), and having a preserved (≥50 %) or reduced (<50 %) ejection fraction (EF+/EF-). TPM data was semi-automatically segmented and global LV torsion was computed for each cardiac time frame for endocardial and epicardial layers, and for the entire myocardium. Results: Maximum myocardial torsion was significantly lower for patients with reduced EF compared to controls (0.21 ± 0.15°/mm vs. 0.36 ± 0.11°/mm, p = 0.018), but also for patients with wall motion abnormalities (0.21 ± 0.13°/ mm vs. 0.36 ± 0.11°/mm, p = 0.004). Global myocardial torsion showed a positive correlation (r = 0.54, p < 0.001) with EF. Moreover, endocardial torsion was significantly higher than epicardial torsion for EF+ subjects (0.56 ± 0.33°/mm vs. 0.34 ± 0.18°/mm, p = 0.039) and for volunteers (0.46 ± 0.16°/mm vs. 0.30 ± 0.09°/mm, p = 0.004). The difference in maximum torsion between endo-and epicardial layers was positively correlated with EF (r = 0.47, p = 0.002) and age (r = 0.37, p = 0.016) for all subjects.
2009, Computerized Medical Imaging and Graphics
2011, Medical Image Analysis
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 still open. This paper is a review of fully and
2014
2011, Information processing in medical imaging : proceedings of the ... conference
This work studies the convex relaxation approach to the left ventricle (LV) segmentation which gives rise to a challenging multi-region seperation with the geometrical constraint. For each region, we consider the global Bhattacharyya metric prior to evaluate a gray-scale and a radial distance distribution matching. In this regard, the studied problem amounts to finding three regions that most closely match their respective input distribution model. It was previously addressed by curve evolution, which leads to sub-optimal and computationally intensive algorithms, or by graph cuts, which result in heavy metrication errors (grid bias). The proposed convex relaxation approach solves the LV segmentation through a sequence of convex sub-problems. Each sub-problem leads to a novel bound of the Bhattacharyya measure and yields the convex formulation which paves the way to build up the efficient and reliable solver. In this respect, we propose a novel flow configuration that accounts for la...
The aim of this project is to design a generic formalism for parietal and regional tracking of the left ventricle (LV) and to adapt it to 3D+t cardiac imaging modalities used in clinical routine (echocardiography, gated-SPECT, cine-MRI). The estimated displacement field must be reliable enough and insensitive to various artifacts to assess regional myocardial function in 3D from the accurate and precise computation of strain. The strain has recently proved to be of great interest for diagnosis and prognostic in cardiology, but its interpretation remains difficult because of the relative nature of the indices. The clinical objective of the 3DStrain project is to bring answers about the knowledge of normality.
2013, Computerized Medical Imaging and Graphics
2006, Journal of Magnetic Resonance Imaging
2010, The International Journal of Cardiovascular Imaging
2009, Journal of Cardiovascular Magnetic Resonance
2009, Journal of Cardiovascular Magnetic Resonance - J CARDIOVASC MAGN RESON
2010, Image and Vision Computing
2009, Journal of Cardiovascular Magnetic Resonance
2009, Journal of Cardiovascular Magnetic Resonance
2009, Journal of Cardiovascular Magnetic Resonance
2009, Journal of Cardiovascular Magnetic Resonance
2012, Computerized Medical Imaging and Graphics
2009, Journal of Cardiovascular Magnetic Resonance
2009, Journal of Cardiovascular Magnetic Resonance
2009, American Journal of Roentgenology
2009, Journal of …
2009, Journal of Cardiovascular Magnetic Resonance
2009, Journal of Cardiovascular Magnetic Resonance
2009, Journal of Cardiovascular Magnetic Resonance
2009, Journal of Cardiovascular Magnetic Resonance
IntroductionFibrin is an abundant component of thrombi and an early marker of ruptured atherosclerotic plaques, which are the major cause of myocardial ischemia and stroke. Identification of fibrin could help detect ruptured plaques and direct therapeutic interventions to prevent or ameliorate the consequences of a heart attack or stroke. Fibrin-targeted perfluorocarbon nanoparticles provide a unique platform for molecular imaging of thrombi by MRI. The particle surface can be formulated with MRI contrast agents, such as PARACEST (PARAmagnetic Chemical Exchange Saturation Transfer) chelates that can provide "contrast on demand" by simply turning on and off a prepulse. In addition, the perfluorocarbon core can be exploited for19F imaging.19F offers high signal intensity and no background signal from biological tissues, yielding a unique signature.PurposeTo combine PARACEST and19F imaging for the corroborative detection of thrombi and quantitating the binding of targeted nanoparticles. ...
2009, Journal of Cardiovascular Magnetic Resonance
2009, Journal of Cardiovascular Magnetic Resonance
2009, Journal of Cardiovascular Magnetic Resonance
2009, Journal of Cardiovascular Magnetic Resonance
2009, Journal of Cardiovascular Magnetic Resonance
2009, Journal of Cardiovascular Magnetic Resonance
2009, Journal of Cardiovascular Magnetic Resonance
2009, Journal of Cardiovascular Magnetic Resonance
2009, Journal of Cardiovascular Magnetic Resonance
2009, Journal of Cardiovascular Magnetic Resonance
Electrical dyssynchrony associated with prolonged QRS duration is a commonly used criterion to select symptomatic heart failure patients for cardiac resynchronization therapy (CRT). However, there is concern that electrical dyssynchrony criterion is inadequate as 3040% ...
2009, Journal of Cardiovascular Magnetic Resonance
2009, Journal of Cardiovascular Magnetic Resonance
2009, Journal of Cardiovascular Magnetic Resonance
2009, Journal of Cardiovascular Magnetic Resonance
2009, Journal of Cardiovascular Magnetic Resonance