Evaluation of DMSA SPECT motion correction in children

Objectives SPECT is an important component of DMSA scans. In children, it is often subjected to motion artifacts that may degrade its quality and require repeat acquisition or correction by dedicated software. We evaluated the impact of motion correction on DMSA SPECT in children.

Methods DMSA scans of 72 children (2 months- 18 years old, mean 39 months) with motion artifacts in raw SPECT projection data were retrospectively analyzed. SPECT motion artifacts were corrected with dedicated software (MDC, GE Medical Systems). Corrected and uncorrected projections were processed with similar iterative reconstruction parameters and read jointly by 2 interpreters in random order. Corrected and uncorrected reconstructions of each study were compared for image quality (using a quality score ranging from1-poor to 5-excellent), image interpretation and diagnostic confidence (1-low, 2 intermediate, 3 high).

Results Image quality and diagnostic confidence scores were significantly higher in motion corrected compared to non corrected reconstructions (4.3+/- 0.7 vs. 3.5 +/-1.2 p<0.0001 and 2.6 +/- 0.6 vs. 2.2 +/- 0.7 , p=0.0003 respectively).Corrected studies yielded different interpretations from uncorrected studies in 43% of the cases. Normal results were encountered in 51% of corrected studies and in 33% of uncorrected studies (p=0.004).

Conclusions Applying motion correction to DMSA SPECT in children improved reconstructed image quality, increased the diagnostic confidence, affected study interpretations and reduced the number of studies with abnormal results.