Journal of magnetic resonance imaging : JMRI
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J Magn Reson Imaging · Jan 2011
Advanced morphological 3D magnetic resonance observation of cartilage repair tissue (MOCART) scoring using a new isotropic 3D proton-density, turbo spin echo sequence with variable flip angle distribution (PD-SPACE) compared to an isotropic 3D steady-state free precession sequence (True-FISP) and standard 2D sequences.
To evaluate a new isotropic 3D proton-density, turbo-spin-echo sequence with variable flip-angle distribution (PD-SPACE) sequence compared to an isotropic 3D true-fast-imaging with steady-state-precession (True-FISP) sequence and 2D standard MR sequences with regard to the new 3D magnetic resonance observation of cartilage repair tissue (MOCART) score. ⋯ Different isotropic sequences can be used for the 3D evaluation of cartilage repair with the benefits of isotropic 3D MRI, MPR, and a significantly reduced scan time, where the 3D PD-SPACE sequence reveals the best results.
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J Magn Reson Imaging · Jan 2011
Optimization of single injection liver arterial phase gadolinium enhanced MRI using bolus track real-time imaging.
To measure contrast agent enhancement kinetics in the liver and to further evaluate and develop an optimized gadolinium enhanced MRI using a single injection real-time bolus-tracking method for reproducible imaging of the transient arterial-phase. ⋯ Our results show detailed timing window analysis required for optimized arterial real-time bolus-triggering acquisition of transient arterial phase features of liver lesions, with optimized arterial triggering expected to improve reproducibility in a significant number of patients.
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J Magn Reson Imaging · Jan 2011
Papillary muscle involvement in myocardial infarction: initial results using multicontrast late-enhancement MRI.
We hypothesized that multicontrast late-enhancement (MCLE) MRI would improve the identification of papillary muscle involvement (PM-MI) in patients with myocardial infarction (MI), compared with conventional late gadolinium enhancement (LGE) MRI using the inversion recovery fast gradient echo (IR-FGRE) technique. Cardiac LGE-MRI studies using both MCLE and IR-FGRE pulse sequences were performed on a 1.5 Tesla (T) MRI system in 23 patients following MI. In all patients, PM-MI was confirmed by the diagnostic criteria as outlined below: (a) the increased signal intensity of PM was the same or similar to that of adjacent hyper-enhanced left ventricular (LV) infarct segments; and (b) the hyper-enhanced PM region was limited to the PM area defined by precontrast cine images of steady-state free precession (SSFP). ⋯ The CNRs of infarct versus viable myocardium did not demonstrate a significant statistical difference (n = 23, P = 0.61) between MCLE (14.4 ± 7.0) and IR-FGRE images (13.6 ± 6.1). MCLE clearly demonstrated PM-MI in all cases (100%, 23/23) while only 39% (9/23) could be visualized on the corresponding IR-FGRE images. In conclusion, MCLE imaging provides better contrast between blood pool and infarct myocardium, thus improving the determination of PM-MI.
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J Magn Reson Imaging · Jan 2011
Preliminary evidence of altered gray and white matter microstructural development in the frontal lobe of adolescents with attention-deficit hyperactivity disorder: a diffusional kurtosis imaging study.
To investigate non-Gaussian water diffusion using diffusional kurtosis imaging (DKI) to assess age effects on gray matter (GM) and white matter (WM) microstructural changes in the prefrontal cortex (PFC) of adolescents with attention-deficit hyperactivity disorder (ADHD) compared to typically developing controls (TDC). ⋯ These findings support the prevailing theory that ADHD is a disorder affecting frontostriatal WM. Our study is the first to directly quantify an aberrant age-related trajectory in ADHD within GM microstructure, suggesting that the assessment of non-Gaussian directional diffusion using DKI provides more sensitive and complementary information about tissue microstructural changes than conventional diffusion imaging methods.
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J Magn Reson Imaging · Jan 2011
Comparative StudyQuantification of fat infiltration in oculopharyngeal muscular dystrophy: comparison of three MR imaging methods.
To analyze and compare three quantitative MRI methods to determine the degree of muscle involvement in oculopharyngeal muscular dystrophy (OPMD). ⋯ Quantitative MR techniques, such as fast multiecho Dixon methods and T₂ imaging, can reliably differentiate between healthy and dystrophic muscles in OPMD, even if muscles are only marginally affected. Quantitative methods thus represent a promising tool that may be able to monitor more objectively the individual disease progression and treatment response in future clinical trials in muscular dystrophies.