Does a k-Space Span Limitation Affect MRI Resolution?
نویسندگان
چکیده
It is common practice to employ conceptual models for data interpretation that are continuous even for data that are discrete. Conclusions drawn from analytical Fourier transform integrals do not automatically apply for discrete data. The conventional sampling point spread function width of 1.2 pixels in MRI is a prime example of this problem. Direct calculation reveals that the k-space span limitation, expressed in terms of a simple sinc function, makes no impact on discrete data samples in the reciprocal image domain. In this article we show that it is the discretization and discrete Fourier transformation that causes image distortion, rather than the limited k-space coverage. © 2006 Wiley Periodicals, Inc. Concepts Magn Reson Part B (Magn Reson Engineering) 29B: 55–61, 2006
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