SPECT liver imaging using an iterative attenuation correction algorithm and an external flood source.

The results obtained from the inclusion of a new intrinsic attenuation correction algorithm into a protocol for SPECT liver imaging are presented in this study. A total of six patients were evaluated with this protocol. The new algorithm uses a transmission tomographic acquisition that is obtained before a standard emission tomograph, and requires the use of an external flood source. The transmission tomograph results in an attenuation image, or map, of the patient. The attenuation map then serves as input into the final intrinsic correction algorithm, that also uses data from a standard emission acquisition. The results of the six patients studied show that the algorithm can correct for attenuation effects without degrading image quality. In all the cases studied, the attenuation corrected images made the cases easier to interpret than did the images obtained without attenuation correction.