Journal of magnetic resonance imaging : JMRI
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J Magn Reson Imaging · May 2006
Clinical TrialMangafodipir trisodium-enhanced MRI for the detection and characterization of focal hepatic lesions: is delayed imaging useful?
To investigate the usefulness of early and delayed hepatic MRI after mangafodipir trisodium (Mn-DPDP) administration for the detection and characterization of focal hepatic lesions. ⋯ Postcontrast delayed MR images after Mn-DPDP administration were helpful in distinguishing hepatocellular from nonhepatocellular lesions, but were not useful for lesion detection and had limited utility for lesion characterization, since benign and malignant hepatic lesions looked the same.
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J Magn Reson Imaging · May 2006
Accelerating MR elastography: a multiecho phase-contrast gradient-echo sequence.
To demonstrate the feasibility of using a multiecho phase-contrast (PC) gradient-echo sequence with motion-sensitizing gradient (MSG) to accelerate MR elastography (MRE) acquisitions in comparison to single-echo PC sequences. ⋯ The results demonstrate that a multiecho sequence is suitable for accelerating MRE in nearly homogeneous tissue, such as muscle. It provides equivalent elasticity values in a significantly reduced scan time compared to a single-echo sequence. The maximum achievable ETL factor must be individually determined for the target tissue.
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J Magn Reson Imaging · May 2006
Clinical TrialGradient- and spin-echo T2-weighted imaging for SPIO-enhanced detection and characterization of focal liver lesions.
To evaluate superparamagnetic iron oxide (SPIO)-enhanced breathhold T2-weighted GRASE imaging in detection and characterization of focal liver lesions. ⋯ GRASE is faster and more sensitive to SPIO than FSE, but its sensitivity and specificity were slightly inferior to those of BH-FSE. Image quality is a current limitation.
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J Magn Reson Imaging · Apr 2006
Effect of contrast enhancement on the measurement of carotid arterial lumen and wall volume using MRI.
To investigate whether gadolinium (Gd)-based contrast enhancement (CE) affects high-resolution magnetic resonance imaging (MRI) measurements of carotid arterial wall volume. ⋯ Gd CE causes a significant increase in the apparent volume of the carotid wall throughout multiple carotid artery locations, which may be associated with improved visibility or neovascularization.
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J Magn Reson Imaging · Apr 2006
Comparative StudyT1rho relaxation mapping in human osteoarthritis (OA) cartilage: comparison of T1rho with T2.
To quantify the spin-lattice relaxation time in the rotating frame (T1rho) in various clinical grades of human osteoarthritis (OA) cartilage specimens obtained from total knee replacement surgery, and to correlate the T1rho with OA disease progression and compare it with the transverse relaxation time (T2). ⋯ Preliminary results from a limited number of knee specimens (N = 8) suggest that T1rho relaxation mapping is a sensitive noninvasive marker for quantitatively predicting and monitoring the status of macromolecules in early OA. Furthermore, T1rho has a higher dynamic range (>100%) for detecting early pathology compared to T2. This higher dynamic range can be exploited to measure even small macromolecular changes with greater accuracy compared to T2. Because of these advantages, T1rho relaxation mapping may be useful for evaluating early OA therapy.