Introduction
Methods
Patients
Image acquisition
Image analysis
Image quality
Quantitative analysis
Diagnostic performance of PET series using the SubtlePET® denoising algorithm
Statistical analysis
Results
Population
Median | Mean | Min | Max | |
---|---|---|---|---|
Age years | 67 | 67.56 | 55 | 81 |
Weight kg | 84 | 83.4 | 63 | 116 |
Injected activity MBq | 164 | 174.1 | 118 | 453 |
Activity/kg MBq/kg | 1.97 | 2.09 | 1.51 | 5.03 |
Initial PSA ng/mL | 11 | 10.7 | 5.7 | 17.46 |
Last PSA before PET ng/mL | 0.682 | 2.356 | 0.23 | 20 |
n | |||
---|---|---|---|
Initial Gleason score | 6 | 1 | |
7 | 24 | ||
3 + 4 | 12 | ||
4 + 3 | 12 | ||
8 | 3 | ||
9 | 1 | ||
Not available | 1 | ||
Initial ISUP score | 1 | 1 | |
2 | 12 | ||
3 | 12 | ||
4 | 3 | ||
5 | 1 | ||
Not available | 1 | ||
Initial treatment | Prostatectomy | 26 | |
Radiotherapy | 3 | ||
None | 1 |
Number and localization of lesions
QC4 | SQC1 | SQC2 | SQC3 | SQC4 | VP4 | SVP1 | SVP2 | SVP3 | SVP4 | Total | |
---|---|---|---|---|---|---|---|---|---|---|---|
REFERENT | 67 | 62 | 62 | 64 | 67 | 71 | 65 | 63 | 69 | 68 | 658 |
− | 9 | 11 | 13 | 11 | 9 | 10 | 9 | 12 | 8 | 8 | 100 |
Equivocal − | 11 | 9 | 5 | 9 | 13 | 13 | 12 | 6 | 16 | 13 | 107 |
Equivocal | 6 | 8 | 7 | 7 | 8 | 6 | 7 | 6 | 8 | 10 | 73 |
Equivocal + | 9 | 4 | 6 | 6 | 6 | 11 | 6 | 7 | 6 | 6 | 67 |
+ | 32 | 30 | 31 | 31 | 31 | 31 | 31 | 32 | 31 | 31 | 311 |
SENIOR | 57 | 58 | 57 | 58 | 57 | 57 | 59 | 57 | 57 | 57 | 574 |
− | 1 | 4 | 2 | 2 | 1 | 1 | 4 | 2 | 1 | 1 | 19 |
Equivocal − | 12 | 10 | 11 | 15 | 15 | 10 | 12 | 10 | 12 | 13 | 120 |
Equivocal | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 10 |
Equivocal + | 7 | 7 | 7 | 5 | 5 | 6 | 5 | 7 | 8 | 6 | 63 |
+ | 36 | 36 | 36 | 35 | 35 | 39 | 37 | 37 | 35 | 36 | 362 |
JUNIOR | 68 | 68 | 69 | 68 | 68 | 72 | 69 | 70 | 68 | 67 | 687 |
− | 6 | 7 | 7 | 7 | 7 | 5 | 8 | 8 | 6 | 6 | 67 |
Equivocal − | 5 | 4 | 10 | 3 | 6 | 2 | 6 | 4 | 3 | 1 | 44 |
Equivocal | 4 | 2 | 4 | 4 | 5 | 3 | 6 | 6 | 7 | 9 | 50 |
Equivocal + | 13 | 14 | 11 | 14 | 13 | 12 | 11 | 12 | 12 | 12 | 124 |
+ | 40 | 41 | 37 | 40 | 37 | 50 | 38 | 40 | 40 | 39 | 402 |
Total | 192 | 188 | 188 | 190 | 192 | 200 | 193 | 190 | 194 | 192 | 1919 |
Image quality analysis
Overall image quality and interpretability
VPFX
Q.Clear
Lesion detectability
Analysis of quantitative parameters
Influence of the denoising algorithm on lesion SUVmax
Series | Mean of SUVmax lesion | Difference SUVmax lesion | CI 95% of Difference of SUVmax lesion | p adjusted | Bias (%) |
---|---|---|---|---|---|
QC4 | 8.91 | ||||
SQC1 | 8.30 | 0.49 | (− 0.27–1.31) | 0.187 | − 5 |
SQC2 | 7.52 | 0.96 | (0.45–1.58) | 0.002 | − 15 |
SQC3 | 7.61 | 1.17 | (0.74–1.72) | < 0.001 | − 16 |
SQC4 | 7.41 | 1.41 | (0.93–1.88) | < 0.001 | − 18 |
VP4 | 7.70 | ||||
SVP1 | 6.67 | 0.97 | (0.11–1.91) | 0.036 | − 14 |
SVP2 | 6.82 | 0.95 | (0.54–1.78) | 0.006 | − 16 |
SVP3 | 6.67 | 1.08 | (0.6–1.75) | 0.006 | − 18 |
SVP4 | 6.72 | 1.18 | (0.83–1.56) | 0.001 | − 17 |
Influence of the denoising algorithm on background uptake SUV (Appendix 1)
Influence of the denoising algorithm on signal-to-background ratio (Table 5)
Series | Mean | Difference SBR | CI 95% of difference | p adjusted | Bias (%) |
---|---|---|---|---|---|
Signal/Background = SUVmax lesion/SUVmean aorta
| |||||
QC4 | 5.28 | ||||
SQC1 | 4.87 | − 0.52 | (− 1.22–0.3) | 0.183 | − 7.8 |
SQC2 | 4.37 | − 0.94 | (− 1.51–0.3) |
0.009
| − 17.2 |
SQC3 | 4.37 | − 1.11 | (− 1.58–0.62) |
0.001
| − 17.2 |
SQC4 | 4.28 | − 1.16 | (− 1.64–0.74) | < 0.001 | − 18.9 |
VP4 | 5.19 | ||||
SVP1 | 4.21 | − 1.08 | (− 2.22–0.07) | 0.054 | − 18.9 |
SVP2 | 4.11 | − 1.29 | (− 2.09–0.58) |
0.007
| − 20.8 |
SVP3 | 4.02 | − 1.66 | (− 2.13–0.56) |
0.006
| − 22.5 |
SVP4 | 4.17 | − 1.27 | (− 2.47–0.8) |
0.002
| − 19.6 |
Signal/Background = SUVmax lesion/SUVmean liver
| |||||
QC4 | 1.13 | ||||
SQC1 | 1.04 | − 0.14 | (− 0.29–0) | 0.061 | − 7.9 |
SQC2 | 0.92 | − 0.19 | (− 0.29–0.08) |
0.002
| − 18.5 |
SQC3 | 0.92 | − 0.22 | (− 0.36–0.14) | < 0.001 | − 18.5 |
SQC4 | 0.88 | − 0.29 | (− 0.42–0.19) | < 0.001 | − 22.1 |
VP4 | 1.07 | ||||
SVP1 | 0.89 | − 0.25 | (− 0.52–0.05) |
0.02
| − 16.8 |
SVP2 | 0.85 | − 0.22 | (− 0.35–0.1) |
0.007
| − 20.6 |
SVP3 | 0.84 | − 0.25 | (− 0.47–0.16) |
0.004
| − 21.5 |
SVP4 | 0.85 | − 0.28 | (− 0.44–0.2) |
0.001
| − 20.6 |
Signal/Background = SUVmax lesion/SUVmean gluteal
| |||||
QC4 | 14.89 | ||||
SQC1 | 15.36 | 0.80 | (2.06–2.94) | 0.456 | 3.2 |
SQC2 | 13.60 | − 1.01 | (− 2.74–1.12) | 0.247 | − 8.7 |
SQC3 | 13.60 | − 1.37 | (− 2.34–0.2) | 0.42 | − 8.7 |
SQC4 | 13.29 | − 2.07 | (− 3.22–0.85) | 0.13 | − 10.7 |
VP4 | 13.96 | ||||
SVP1 | 12.53 | − 1.81 | (− 3.58–0.92) | 0.267 | − 10.2 |
SVP2 | 12.91 | − 0.88 | (− 2.51–0.91) | 0.214 | − 7.5 |
SVP3 | 12.63 | − 1.66 | (− 2.65–0.36) | 0.084 | − 9.5 |
SVP4 | 12.67 | − 1.76 | (− 2.47–0.8) | 0.17 | − 9.2 |
Subgroup analysis
Subgroup analysis by PSA on PET scan
Subgroup analysis by weight
Subgroup analysis by camera
Diagnostic performance (Table 6, Figs. 6 and 7)
Series | Reader | Accuracy (CI 95%) | Adjusted p | Cohen’s Kappa | Sensitivity | Specificity |
---|---|---|---|---|---|---|
VP4 | Referent | 1 | 1 | 1 | 1 | |
Senior | 0.65 (0.48–0.79) | 0.076 | 0.28 | 0.86 | 0.42 | |
Junior | 0.77 (0.64–0.87) | < 0.001 | 0.55 | 0.97 | 0.59 | |
SVP1 | Referent | 0.98 (0.9–1) | < 0.001 | 0.96 | 0.97 | 1 |
Senior | 0.70 (0.53–0.83) |
0.019
| 0.39 | 0.86 | 0.53 | |
Junior | 0.91 (0.8–0.97) | < 0.001 | 0.82 | 0.93 | 0.88 | |
SVP2 | Referent | 0.98 (0.9–1) | < 0.001 | 0.97 | 1 | 0.97 |
Senior | 0.7 (0.53–0.83) |
0.019
| 0.39 | 0.86 | 0.53 | |
Junior | 0.81 (0.68–0.9) | < 0.001 | 0.62 | 0.86 | 0.78 | |
SVP3 | Referent | 1 (0.94–1) | < 0.001 | 1 | 1 | 1 |
Senior | 0.68 (0.5–0.81) |
0.04
| 0.34 | 0.81 | 0.53 | |
Junior | 0.77 (0.64–0.87) | < 0.001 | 0.54 | 0.83 | 0.71 | |
SVP4 | Referent | 1 (0.94–1) | < 0.001 | 1 | 1 | 1 |
Senior | 0.72 (0.56–0.85) |
0.008
| 0.44 | 0.86 | 0.58 | |
Junior | 0.81 (0.68–0.9) | < 0,001 | 0,62 | 0,9 | 0,72 | |
QC4 | Referent | 1 | 1 | 1 | 1 | |
Senior | 0.75 (0.58–0.87) |
0.007
| 0.48 | 0.86 | 0.61 | |
Junior | 0.91 (0.8–0.97) | < 0.001 | 0.82 | 0.93 | 0.88 | |
SQC1 | Referent | 0.98 (0.9–1) | < 0.001 | 0.96 | 0.97 | 1 |
Senior | 0.72 (0.56–0.85) |
0.018
| 0.43 | 0.86 | 0.56 | |
Junior | 0.84 (0.71–0.92) | < 0.001 | 0.67 | 0.9 | 0.77 | |
SQC2 | Referent | 0.98 (0.9–1) | < 0.001 | 0.96 | 0.97 | 1 |
Senior | 0.75 (0.58–0.87) |
0.007
| 0.48 | 0.86 | 0.61 | |
Junior | 0.89 (0.78–0.96) | < 0.001 | 0.78 | 0.93 | 0.85 | |
SQC3 | Referent | 0.98 (0.9–1) | < 0.001 | 0.97 | 0.97 | 1 |
Senior | 0.75 (0.58–0.87) |
0.007
| 0.48 | 0.86 | 0.61 | |
Junior | 0.89 (0.77–0.96) | < 0.001 | 0.78 | 0.93 | 0.85 | |
SQC4 | Referent | 0.98 (0.91–1) | < 0.001 | 0.97 | 0.97 | 1 |
Senior | 0.75 (0.58–0.87) |
0.007
| 0.48 | 0.86 | 0.61 | |
Junior | 0.88 (0.75–0.95) | < 0.001 | 0.75 | 0.9 | 0.85 |