Introduction
Materials and methods
CT technique
Reconstruction algorithms
Quantitative image analysis
Qualitative image analysis
Statistical analysis
Results
Quantitative
FBP | ASIR | MBIR | ||||
---|---|---|---|---|---|---|
Mean noise | ||||||
Mean | 47.65 | 39.36 | 15.74 | |||
SD | 15.84 | 13.40 | 3.74 | |||
Mean attenuation values | ||||||
Mean | −106.74 | −106.75 | −106.58 | |||
SD | 9.68 | 9.70 | 9.66 | |||
Mean contrast-to-noise ratio | ||||||
LT kidney | RT kidney | LT kidney | RT kidney | LT kidney | RT kidney | |
Mean | 3.18 | 3.19 | 3.86 | 3.88 | 9.13 | 9.09 |
SD | 0.97 | 0.97 | 1.20 | 1.20 | 2.02 | 1.82 |
Mean Diff. | 95 % CI | ||
---|---|---|---|
FBP vs. ASIR | 8.285 | 1.252 to 15.32 | p < 0.0001 |
FBP vs. MBIR | 31.91 | 24.88 to 38.94 | p < 0.0001 |
ASIR vs. MBIR | 23.63 | 16.59 to 30.66 | p < 0.0001 |
Qualitative
FBP | ASIR | MBIR | |
---|---|---|---|
Image noise | |||
Mean | 3.23 | 2.95 | 2.05 |
SD | 0.53 | 0.46 | 0.22 |
Lower 95 % CI | 2.98 | 2.74 | 1.95 |
Upper 95 % CI | 3.47 | 3.16 | 2.16 |
Image contrast | |||
Mean | 3.31 | 2.81 | 2.25 |
SD | 0.42 | 0.55 | 0.31 |
Lower 95 % CI | 3.09 | 2.53 | 2.10 |
Upper 95 % CI | 3.52 | 3.08 | 2.40 |
Visibility of kidneys/ureters/bladder | |||
Mean | 3.08 | 3.05 | 2.65 |
SD | 0.24 | 0.28 | 0.33 |
Lower 95 % CI | 2.96 | 2.92 | 2.50 |
Upper 95 % CI | 3.19 | 3.18 | 2.80 |
Visibility of small structures | |||
Mean | 3.13 | 3.10 | 2.73 |
SD | 0.43 | 0.42 | 0.34 |
Lower 95 % CI | 2.93 | 2.91 | 2.56 |
Upper 95 % CI | 3.32 | 3.30 | 2.89 |
Overall diagnostic confidence | |||
Mean | 3.08 | 3.08 | 2.58 |
SD | 0.44 | 0.44 | 0.29 |
Lower 95 % CI | 2.87 | 2.87 | 2.44 |
Upper 95 % CI | 3.28 | 3.28 | 2.71 |
Friedman test | ||
---|---|---|
P value | <0.0001 | |
Friedman statistic | 36.21 | |
Dunn’s multiple comparison test | Difference in rank sum | Significant? P < 0.05? |
ASIR vs. FBP | −9.5 | No |
ASIR vs. MBIR | 24.5 | Yes |
FBP vs. MBIR | 34 | Yes |
Radiation dose
DLP | Effective dose (mSv) | |
---|---|---|
Average | 195.03 | 2.93 |
SD | 138.91 | 2.08 |
Min. | 93.57 | 1.40 |
Max. | 692.49 | 10.39 |