Field Strength Dependence in MRI: Advantages and Artifacts at 3T
نویسنده
چکیده
Although B0 = 1.5T remains the predominant field strength for clinical MRI, 3.0T magnets are making substantial inroads into routine practice. The move to 3.0T is driven mainly by its approximate doubling of the signal-to-noise ratio (SNR) compared to 1.5T. The improved SNR can be used to shorten the acquisition time, to improve spatial resolution at a fixed scan time, or a combination of the two. The scaling of other physical parameters such as the doubling of the susceptibility variation (as measured in hertz) can aid applications like fMRI that use the BOLD effect. Similarly the doubling of the chemical shift (again, measured in hertz) from 1.5 to 3.0T can aid peak separation for spectroscopy.
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تاریخ انتشار 2006