Prenatal ultrasonography is the primary imaging modality in pregnancy as it allows direct real-time fetal examination. Antenatal magnetic resonance imaging (MRI) has so far been of limited clinical value owing to poor image quality. This was due to the long acquisition times that were needed to achi
Reconstruction algorithm for novel ultrafast magnetic resonance imaging
โ Scribed by F. J. Rybicki; S. Patz; M. I. Hrovat; Y. M. Pulyer
- Publisher
- John Wiley and Sons
- Year
- 1999
- Tongue
- English
- Weight
- 195 KB
- Volume
- 10
- Category
- Article
- ISSN
- 0899-9457
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โฆ Synopsis
We introduce a new magnetic field geometry, B x (x, y) ฯญ g y y cos(q x x), to spatially encode magnetic resonance imaging (MRI). The field is called the PERL field since it is PERiodic in x and Linear in y. A technique is proposed to acquire two-dimensional (2D) data without switching the encoding fields. The time-domain PERL signal and image are not related by a two-dimensional Fourier transform (2DFT). They are related by a 1DFT in the x-dimension and a new Bessel function integral transform, called the PERL transform, in the y-dimension. We numerically solve this equation and develop a reconstruction algorithm. The algorithm is evaluated by assuming a known spin density which is then used to calculate the PERL signal. This signal is the input for the algorithm. We show the reconstructed image matches the convolution of the initial assumed spin density and a point spread function (PSF). We identify the PSF and describe the conditions under which it approaches โฆ.
๐ SIMILAR VOLUMES
The mathematical basis and motivation for a new, noninbe more natural, literally, to use gradient fields that varied continterpolative, direct method for reconstructing magnetic resonance imuously instead of being switched. The method of spiral imaging aging (MRI) data is presented. The reconstructi