Comparison of motion correction algorithms for cardiac SPECT.
Patient motion remains a significant source of unsatisfactory cardiac SPECT examinations. The extent to which image recovery can be achieved with correction algorithms is unknown.


METHODS
Nine subjects who had completed motion-free redistribution 201Tlcardiac SPECT subsequently underwent simultaneous dual-isotope (201Tl/99mTc) SPECT with a 99mTc cutaneous point source, while the imaging table was subjected to predefined nonreturning y-translation movements. Cardiac reconstructions, marker reconstructions and marker-compressed dynamic images were generated from the raw data after applying the following correction methods: diverging squares, cross-correlation of the cardiac data and cross-correlation of the marker.


RESULTS
Marker cross-correlation performed significantly better than all other methods with good-excellent results in all evaluations. This compared with good-excellent results in none of 27 for the raw data, in 13 of 27 for cardiac cross-correlation and in 7 of 27 for diverging squares (p < 10(-5)). The superiority of the marker-based method was confirmed on analysis of bullseye difference maps and quantitation of residual motion in the point-source data.


CONCLUSIONS
Motion artifacts can accurately be detected and corrected using cross-correlation of an external point-source. Furthermore, this technique provides useful independent information on the degree of image recovery.
Leslie
W D
WD
Department of Nuclear Medicine, St. Boniface General Hospital, University of Manitoba, Winnipeg, Canada.
Dupont
J O
JO
McDonald
D
D
Peterdy
A E
AE
D000465:Algorithms; D016477:Artifacts; D005080:Exercise Test; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009068:Movement; D017202:Myocardial Ischemia / Q000000981:diagnostic imaging*; D013667:Technetium; D013794:Thallium Radioisotopes; D015899:Tomography, Emission-Computed, Single-Photon
D013794:Thallium Radioisotopes; D013667:Technetium