Imaging methods and apparatus.

摘要

Radiation passing through a cone-beam collimator is received by a radiation detector, such as a gamma camera head (10), as the gamma camera head (10) is moved in a circular orbit and in a line orbit. Data collected during the circular orbit is stored and transformed into the frequency domain and redundant data is removed, and transformed back to the spatial domain. The data collected during the line orbit is stored. The line orbit data is transformed to the frequency domain and repeatedly filtered with a family of filter functions (Fline) to remove redundant data. Each filter function corresponds to a different row through the examination region. The filtered frequency domain slice data sets are transformed back to the spatial domain and transferred to a central portion of a spatial domain memory (58l). Empty memory cells of the memory (58l) are filled with zeros. The spatial domain data from memories (58c, 58l) are filtered, backprojected, and summed into a three-dimensional image representation that is stored in an image memory (78).