Optimization of analog-circuit motion correction for liver scintigraphy.

Respiratory motion customarily degrades the resolution of a routine hepatic scintigram. We have analyzed four analog motion-correction methods and have measured their abilities to maintain good spatial resolution over a broad range of liver scintigraphy parameters. The analog circuit described can maintain the spatial resolution of the scintillation camera within 2 mm of the full width at half maximum of the stationary point-sread function. Experiments show that clinicians require about 50% greater film-density contrast to detect a 2-cm-diam. lesion if motion correction is not used. In 14% of the cases studied, the addition of a motion-corrected anterior view to the usual four-view liver study (performed without motion correction) resulted in a changed clinical interpretation. We conclude that analog motion correction should be provided in all scintillation cameras used for liver scintigraphy.