Journal of magnetic resonance imaging : JMRI
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J Magn Reson Imaging · Dec 2008
Comparative StudyHead-to-head comparison between delayed enhancement and percent infarct mapping for assessment of myocardial infarct size in a canine model.
To compare a novel method, percent-infarct-mapping (PIM), with conventional delayed enhancement (DE) of contrast for accurate myocardial viability assessment. Contrary to signal intensity (SI), the longitudinal relaxation-rate enhancement (DeltaR1) is an intrinsic parameter linearly proportional to the concentration of contrast agent (CA). Determining DeltaR1 voxel-by-voxel, after administering an infarct-avid CA, allows determination of per-voxel percentage of infarcted tissue. The feasibility of generating PIM is demonstrated in canine reperfused infarction using an infarct-avid, persistent-CA (PCA), (Gd)(ABE-DTTA). PIM is compared to the DE method using Gd(DTPA), and both to triphenyltetrazolium chloride (TTC) staining histochemistry. ⋯ The DeltaR1-based PIM method is highly reproducible and more accurate than DE for quantifying myocardial viability in vivo.
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J Magn Reson Imaging · Dec 2008
Perfusion imaging of the pancreas using an arterial spin labeling technique.
To investigate the feasibility of perfusion imaging of the pancreas using an arterial spin labeling (ASL) technique. ⋯ FAIR-TrueFISP permits analysis of pancreatic tissue perfusion with good image quality in a clinically applicable measuring time. Assessment of perfusion disorders may be useful in the diagnosis of inflammatory pancreatic pathologies, endocrine and exocrine pancreatic disorders, and in monitoring of pancreatic transplants.
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J Magn Reson Imaging · Nov 2008
Time-resolved dynamic contrast-enhanced MR urography for the evaluation of ureteral peristalsis: initial experience.
To determine the feasibility of time-resolved dynamic contrast-enhanced magnetic resonance urography (MRU) for the evaluation of ureteral peristalsis using a data-sharing 3D gradient echo sequence with spiral k-space filling. ⋯ MRU using a time-resolved, data-sharing 3D contrast-enhanced technique is able to demonstrate ureteral peristalsis and permits quantification of ureteral peristaltic frequency.
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J Magn Reson Imaging · Nov 2008
Effective motion-sensitizing magnetization preparation for black blood magnetic resonance imaging of the heart.
To investigate the effectiveness of flow signal suppression of a motion-sensitizing magnetization preparation (MSPREP) sequence and to optimize a 2D MSPREP steady-state free precession (SSFP) sequence for black blood imaging of the heart. ⋯ Velocity encoding is the primary flow suppression mechanism of the MSPREP sequence and 2D MSPREP-SSFP black blood imaging of the heart is feasible in healthy subjects.
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J Magn Reson Imaging · Nov 2008
Role of spectral presaturation attenuated inversion-recovery fat-suppressed T2-weighted MR imaging in active inflammatory bowel disease.
To retrospectively evaluate the efficacy of spectral presaturation attenuated inversion-recovery (SPAIR) fat-suppressed (FS) partial Fourier single shot (SSH) T2-weighted (T2W) and gadolinium-enhanced (Gd) FS 3D-gradient echo (3DGRE) T1-weighted (T1W) delayed phase MRI to differentiate active bowel inflammation from fibrotic disease in patients with Crohn's disease (CD). ⋯ SPAIR-SSH detects actively diseased CD bowel segments with a high level of specificity. Noninflammatory bowel fibrosis corresponds to abnormal uptake on delayed phase Gd-3DGRE images but without associated elevated abnormal signal on SPAIR-SSH.