Journal of magnetic resonance imaging : JMRI
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J Magn Reson Imaging · Dec 2006
Statistical representation of mean diffusivity and fractional anisotropy brain maps of normal subjects.
To create diffusion tensor atlases from echo planar imaging (EPI) images acquired at 3 T in 10 normal subjects. ⋯ A high-resolution, diffusion MR atlas with full brain coverage was developed. Additionally, maps of the SD of the diffusion indices were also generated to provide an estimate of the variance within a normal population. Active shape and texture models were also generated for the corpus callosum as an alternate method of representing the variance in morphology and diffusion indices.
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J Magn Reson Imaging · Dec 2006
Comparative StudyFat suppression with spectrally selective inversion vs. high spectral and spatial resolution MRI of breast lesions: qualitative and quantitative comparisons.
To compare conventional fat-suppressed MR images of the breast to images derived from high spectral and spatial resolution MR data. Image quality and the level of fat suppression are compared qualitatively and quantitatively. ⋯ The results demonstrate that the water peak height images obtained from HiSS data potentially could improve the quality of fat suppression, detection and diagnosis of breast cancer. HiSS allowed detection of lesions and evaluation of lesion morphology prior to contrast media injection. J. Magn. Reson. Imaging 2006. (c) 2006 Wiley-Liss, Inc.
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To describe and evaluate a fast, fluid-suppressed 2D multislice steady-state free precession (SSFP) neuroimaging sequence. ⋯ We have demonstrated the feasibility of a very fast fluid-suppressed neuroimaging technique using SSFP.
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J Magn Reson Imaging · Dec 2006
Comparative StudyDifferentiation of hepatocellular carcinoma and hepatic metastasis from cysts and hemangiomas with calculated T2 relaxation times and the T1/T2 relaxation times ratio.
To determine the diagnostic capability of the T1 and T2 relaxation times and the T1/T2 relaxation times ratio generated with the mixed turbo spin echo (mixed-TSE) pulse sequence, in order to discriminate between hepatocellular carcinoma (HCC)/metastases and hemangiomas/cysts. ⋯ Although there is high sensitivity and specificity associated with the use of T2 relaxation times alone to discriminate carcinoma/metastases from hemangiomas/cysts, using the T1/T2 relaxation times ratio threshold of 5.8 allowed proper classification of all lesions.
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J Magn Reson Imaging · Dec 2006
Cerebral vascular response to hypercapnia: determination with perfusion MRI at 1.5 and 3.0 Tesla using a pulsed arterial spin labeling technique.
To compare the quantification of cerebral blood flow (CBF) at 1.5 and 3.0 Tesla, under normo- and hypercapnia, and to determine the cerebral vascular response (CVR) of gray matter (GM) to hypercapnia, a pulsed arterial spin labeling technique was used. Additionally, to improve GM CBF quantification a high-resolution GM-mask was applied. ⋯ The method presented allows for the quantification of CBF and CVR in GM at the common clinical field strengths of 1.5 and 3.0 Tesla and could therefore be a useful tool to study these parameters under physiological and pathophysiological conditions.