Quantitative and Visual Benefits of Data-Driven Motion Correction on Oncologic PET/CT: A Prospective Cross-sectional Study.

RATIONALE AND OBJECTIVE

Conventional positron emission tomography (PET) respiratory gating utilizes a fraction of acquired PET counts (i.e., optimal gate [OG]), whereas elastic motion correction with deblurring (EMCD) utilizes all PET counts to reconstruct motion-corrected images without increasing image noise. Our aim was to assess the quantitative and visual impacts of EMCD-based motion correction on FDG-PET and DOTATATE-PET images relative to OG and ungated (UG) images.

MATERIALS AND METHODS

This prospective, single-center study enrolled adults undergoing FDG or DOTATATE oncologic PET/CT between June 2020 and October 2022. Subjects underwent a standard-of-care (SOC) PET acquisition while wearing a respiratory gating belt. UG, belt-gating-derived optimal gate (BG-OG), EMCD utilizing belt gating (BG-EMCD), and EMCD utilizing data-driven gating (DDG-EMCD) images were reconstructed. Tracer-avid lesions in the lower chest or upper abdomen were segmented. Quantitative metrics were extracted. Two independent, blinded readers assessed image quality via a 4-point scale and counted lesions on each reconstruction. Differences between reconstructions were assessed via the Wilcoxon signed-rank test (alpha, 0.05).

RESULTS

This study enrolled 78 subjects; 36 subjects (mean age, 64.8 years; 20 males) with 136 tracer-avid lesions were analyzed. Data provided are medians across all tracers. Lesion SUV-max was significantly higher (P<0.001) on motion-corrected images (BG-OG: 10.77, BG-EMCD: 10.75, DDG-EMCD: 10.74) than UG images (9.00). Lesion contrast-to-noise ratios (CNRs) were significantly lower (P<0.001) for BG-OG (6.31) and UG images (7.89) than BG-EMCD (9.14) and DDG-EMCD (8.89) images. FDG and DOTATATE subgroup analyses produced similar results. Among motion-corrected images, both readers preferred EMCD-based images to BG-OG images for all tracers (P<0.001) and both subgroups. EMCD-based images occasionally demonstrated more tracer-avid lesions than BG-OG or UG images.

CONCLUSION

EMCD-based motion correction beneficially impacts lesion quantitation (including higher SUVs and CNRs) and overall image quality.

CLINICAL IMPACT

When employed on capable scanners, EMCD can improve the quality of oncologic PET imaging.