Investigative radiology
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Investigative radiology · Jun 2007
Comparative StudyHigh-resolution whole-body magnetic resonance imaging applications at 1.5 and 3 Tesla: a comparative study.
To analyze the impact of altered magnetic field properties on image quality and on potential artifacts when an established whole-body magnetic resonance imaging (WB-MRI) protocol at 1.5 Tesla (T) is migrated to 3 T. ⋯ Three Tesla WB-MRI is feasible with good image quality comparable to 1.5 T. 3.0 T WB-MRI shows significantly more artifacts with a mild to moderate impact on image assessment. Therefore 1.5 T WB-MRI is the preferred image modality. Overall scan time at 3 T is reduced with the use of parallel imaging at a constant image resolution.
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Investigative radiology · Jun 2007
Inversion recovery single-shot TurboFLASH for assessment of myocardial infarction at 3 Tesla.
The aim of the study was to assess the diagnostic accuracy of imaging myocardial infarction with a single-shot inversion recovery turbofast low-angle shot (SS IR turboFLASH) sequence at 3.0 Tesla in comparison with an established segmented inversion recovery turboFLASH sequence at 1.5 Tesla. ⋯ The loss of CNR, which is caused by replacement of the segmented technique by the single-shot technique, is completely compensated by the approximately 2-fold CNR increase at the higher field strength. The IR turboFLASH technique at 3.0 Tesla IR can be used as a single-shot technique with acquisition of 9 slices during a single breath-hold without loss of diagnostic accuracy compared with the segmented technique at 1.5 Tesla.
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Investigative radiology · Jun 2007
High-resolution magnetic resonance angiography of the lower extremities with a dedicated 36-element matrix coil at 3 Tesla.
Recent developments in hard- and software help to significantly increase image quality of magnetic resonance angiography (MRA). Parallel acquisition techniques (PAT) help to increase spatial resolution and to decrease acquisition time but also suffer from a decrease in signal-to-noise ratio (SNR). The movement to higher field strength and the use of dedicated angiography coils can further increase spatial resolution while decreasing acquisition times at the same SNR as it is known from contemporary exams. The goal of our study was to compare the image quality of MRA datasets acquired with a standard matrix coil in comparison to MRA datasets acquired with a dedicated peripheral angio matrix coil and higher factors of parallel imaging. ⋯ Implementation of a dedicated coil for peripheral MRA at 3.0 Tesla helps to increase spatial resolution and to decrease acquisition time while the image quality could be kept equal. Venous overlay can be effectively avoided despite the use of high-resolution scans.
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Investigative radiology · Jun 2007
Comparative StudyComparison of the extent of delayed-enhancement cardiac magnetic resonance imaging with and without phase-sensitive reconstruction at 3.0 T.
To evaluate phase-sensitive reconstructed images versus magnitude images generated by an inversion recovery pulse sequence for the determination of myocardial infarct size in delayed-enhancement cardiac magnetic resonance (DE-CMR) at 3 T. ⋯ DE-CMR with phase-sensitive reconstruction at 3.0 T provides similar results to magnitude images, but with a significantly greater CNR between infarcted and normal myocardium.
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Investigative radiology · Jun 2007
3.0 Tesla high spatial resolution contrast-enhanced magnetic resonance angiography (CE-MRA) of the pulmonary circulation: initial experience with a 32-channel phased array coil using a high relaxivity contrast agent.
To evaluate the technical feasibility of high spatial resolution contrast-enhanced magnetic resonance angiography (CE-MRA) with highly accelerated parallel acquisition at 3.0 T using a 32-channel phased array coil, and a high relaxivity contrast agent. ⋯ The described 3 T CE-MRA protocol in addition to high T1 relaxivity of Gd-BOPTA provides sufficient SNR to support highly accelerated parallel acquisition (GRAPPA x 6), resulting in acquisition of isotopic (1 x 1 x 1 mm3) voxels over the entire pulmonary circulation in 20 seconds.