Article Figures & Data
Figures
- FIGURE 1.
Depiction of quiescent period gating (QPG), in which part of respiratory cycle associated with relatively little motion is identified and retained in gated image.
- FIGURE 2.
Box plots showing SUVmax for DDG-retro, minus that obtained from RPM-gated, ungated-matched, or ungated-full. Positive values indicate higher SUVmax in case of DDG-retro. Line on box indicates median.
- FIGURE 3.
Comparison of clinical scoring between DDG-retro and RPM-gated (A), ungated-matched (B), and ungated-full (C). Lower score indicated preference, and hence negative scores represent preference for DDG-retro.
- FIGURE 4.
Considering only those studies with visible lesions in liver, comparison of clinical scoring between DDG-retro and RPM-gated (A), ungated-matched (B), and ungated-full (C). Lower score indicated preference, and hence negative scores represent preference for DDG-retro.
- FIGURE 5.
Coronal slices showing 18F-FDG–avid liver metastasis (indicated by arrows) that is easier to detect and has higher SUVmax on 2 gated reconstructions than without gating. In this example, DDG-retro and RPM-gated images received equal score for overall image quality, and both were considered superior to ungated images. Lesion indicated by arrow was not considered to be definitely visible on ungated-matched image and was borderline-visible on ungated-full image. One can also see reduction in noise in ungated-full image, as compared with other 3 images. Images are on SUV grayscale of 0–6.
- FIGURE 6.
Comparison of noise scoring across 4 image reconstructions. Error bars represent SEs on mean.
Tables
- TABLE 1
Differences in Lesion Quantification Between DDG-Retro and the 3 Other Methods of Gating and Reconstruction
Difference (DDG-retro – other) Parameter/DDG-retro with… Lesions (n) Mean 25th, 75th percentiles P SUVmax/RPM-gated 87 0.66 ± 0.1 g/mL 0.00, 0.87 g/mL <0.0005 SUVmax/ungated-matched 107 1.3 ± 0.2 g/mL 0.06, 2.0 g/mL <0.0005 SUVmax/ungated-full 107 1.6 ± 0.2 g/mL 0.38, 2.0 g/mL <0.0005 SUVmean/RPM-gated 54 0.44 ± 0.1 g/mL −0.01, 0.60 g/mL 0.003 SUVmean/ungated-matched 64 0.97 ± 0.2 g/mL 0.01, 1.60 g/mL <0.0005 SUVmean/ungated-full 64 1.2 ± 0.2 g/mL 0.36, 1.59 g/mL <0.0005 Lesion volume/RPM-gated 54 −0.30 ± 0.1 cm3 −0.52, 0.03 cm3 0.009 Lesion volume/ungated-matched 64 −0.70 ± 0.2 cm3 −0.98, −0.01 cm3 0.005 Lesion volume/ungated-full 64 −0.83 ± 0.2 cm3 −1.05, −0.03 cm3 0.001 Data are mean differences (with SE on mean difference) and first and third quartiles, along with results from post hoc testing of transformed data. P values are uncorrected for multiple comparisons. Critical P value for statistical significance was 0.017 (lowered from 0.05 to allow for multiple comparisons).
