Patent ID: 7756307

Claim:
A method of conducting motion correction for a tomographic scanner including a detector array for detecting radiation to generate detector data, wherein the method comprises: storing detector data collected during a data acquisition period in one of a data store of the scanner and a memory of a computer connected to the scanner, said detector data being indicative of: i) directions along which radiation is detected; and ii) quantities of radiation detected in different of said directions; storing movement data representing movement of the subject during the data acquisition period in one of a data store of the scanner and a memory of a computer connected to the scanner; and motion correcting said detector data using said movement data and a motion correction algorithm to calculate motion corrected detector data, said motion correcting step being performed by a computer connected to the scanner; wherein said motion correcting step comprises processing said detector data by: a) realigning directions of at least some of said detector data on the basis of said movement data; and b) altering quantities of at least some of said detector data on the basis of said movement data, such that at least some of said detector data are both realigned and altered in quantity, wherein said altering quantities step comprises calculating estimates of first detector data based on second, different, detector data, characterised in that said altering quantities step comprises either: selecting whether to scale an original detected quantity of said first detector data upwards or to replace the original detected quantity of said first detector data with a said calculated estimate; or altering the original detected quantity of said first detector data so that the altered quantity takes into account both the original detected quantity and a said calculated estimate.