Journal of magnetic resonance imaging : JMRI
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J Magn Reson Imaging · Jun 2011
Comparative StudyComparison of a single shot T1-weighted in- and out-of-phase magnetization prepared gradient recalled echo with a standard two-dimensional gradient recalled echo: preliminary findings.
To compare in-phase (IP)/out-of-phase (OP) single shot magnetization-prepared gradient-recalled-echo (MP-GRE) with a standard two-dimensional gradient-recalled-echo (2D-GRE), and to compare image quality of MP-GRE in cooperative and noncooperative subjects. ⋯ IP/OP MP-GRE and 2D-GRE comparably demonstrate the presence or absence of hepatic steatosis. Image quality of MP-GRE was also comparable to 2D-GRE, and was not substantially adversely affected if subjects were unable to cooperate with breathholding instructions.
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J Magn Reson Imaging · Jun 2011
Hepatic fat quantification using chemical shift MR imaging and MR spectroscopy in the presence of hepatic iron deposition: validation in phantoms and in patients with chronic liver disease.
To compare the accuracy of four chemical shift magnetic resonance imaging (MRI) (CS-MRI) analysis methods and MR spectroscopy (MRS) with and without T2-correction in fat quantification in the presence of excess iron. ⋯ T2*- or T2-correction methods are effective in correcting the confounding effects of iron, enabling an accurate fat quantification throughout a wide range of iron concentrations. Spectral modeling of fat may further improve the accuracy of CS-MRI in fat quantification.
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J Magn Reson Imaging · Jun 2011
Adiabatic localized correlation spectroscopy (AL-COSY): application in muscle and brain.
To describe an enhanced version of a localized correlation spectroscopy (L-COSY) by introducing adiabatic radiofrequency (RF) pulses for localization in two dimensions. Adiabatic pulses will improve slice selection profile and reduce chemical shift artifacts. Optimized Mao and adiabatic hyperbolic secant pulses are tested in vivo. ⋯ The AL-COSY sequence is an improved sequence due to sharper slice selection profiles, reduction of chemical shift artifacts, peak volume improvements in 2D techniques, and less J-modulation.
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J Magn Reson Imaging · May 2011
Right ventricular outflow tract obstruction as a confounding factor in the assessment of the impact of pulmonary regurgitation on the right ventricular size and function in patients after repair of tetralogy of Fallot.
To compare right ventricular (RV) size and function between patients with combined pulmonary regurgitation (PR) plus RV outflow tract (RVOT) obstruction (RVOTO) and patients with isolated PR. ⋯ Patients with combined PR+RVOTO had smaller RV volumes and higher RVEF when compared with patients with isolated PR. The confounding effect of RVOTO on RV size and function needs to be considered in CMR studies evaluating patients after TOF repair.
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J Magn Reson Imaging · May 2011
Whole-body MRI including diffusion-weighted imaging (DWI) for patients with recurring prostate cancer: technical feasibility and assessment of lesion conspicuity in DWI.
To evaluate the principal methodological aspects of whole-body magnetic resonance imaging (MRI) including diffusion-weighted imaging (DWI) with background suppression using a time-optimized protocol for restaging of prostate cancer patients in a technical feasibility study. ⋯ In patients with recurrent prostate cancer a whole-body MR protocol including DWI is technically robust. Due to the high CNR of DWI compared to T1w and T2w STIR, detection of malignant lesions should be facilitated by DWI, except for sclerotic bone metastases.