[Impact of patient motion on myocardial perfusion imaging with double-head SPECT and assessment of motion correction].

Objective: To investigate the impact of patient motion on myocardial perfusion imaging with double-head Single Photon Emission Computed Tomography (SPECT) and assess the effect of motion correction.

Methods: Twenty (20) patients were included in the study. Acquisitions were performed for all patients under the situations with or without body motion respectively. Images were reconstructed without or with motion correction software separately. The extent of perfusion defects was assessed by QPS (Quantitative Perfusion SPECT) with a 20 -segment, 5-point scoring system.

Results: The extent of artifacts and perfusion defects was related to the extent (r = 0.58, P < 0.01) and frequency (r = 0.811, P < 0.01) of patient motion. The image quality was improved in 18 of 20 patients (900%) significantly after motion correction (P < 0.05). Only 2.2% (7/318) of segments that were previously considered normal (score = 0 or 1) changed to abnormal (score = 2-4) after motion correction, whereas 35.3% (29/82) of abnormal segments were reclassified as normal after motion correction.

Conclusion: Motion correction is necessary in myocardial perfusion imaging reconstruction if the range of patient motion is out of one pixel or the motion frequency is more than one time. But the correction is not helpful when the extent of body motion exceeds 3 pixel or the motion frequency is over one time.