16-01-2013, 10:43 AM
Reconstruction from Projections
1Reconstruction.pdf (Size: 1.16 MB / Downloads: 223)
2nd step in tomography = reconstruction
from projections
Analytic reconstruction methods (e.g. the filtered backprojection
algorithm) are efficient (fast) and elegant, but
they are unable to handle complicated factors such as
scatter. Filtered back projection has been used for
reconstructions in x-ray CT and for most SPECT and PET
reconstructions until recently.
Iterative reconstruction algorithms, on the other hand,
are more versatile but less efficient. Efficient (that is - fast)
iterative algorithms are currently under development. With
rapid increases being made in computer speed and
memory, iterative reconstruction algorithms will be used in
more and more applications of SPECT and PET and will
enable more quantitative reconstructions.