Table 3.
Mean and standard deviation of differences between organ dose simulated by Monte Carlo (gold standard) and estimated by convolution method for chest scans. The difference was normalized by the CTDIvol of the exam to derive the percentage difference.
|
a = 1
|
a = 0.75
|
a = 0.5
|
a = 0.25
|
|||||
|---|---|---|---|---|---|---|---|---|
| Avg (%) | Std (%) | Avg (%) | Std (%) | Avg (%) | Std (%) | Avg (%) | Std (%) | |
| Kidneys | 3.5 | 3.3 | 3.8 | 3.9 | 4.3 | 5.0 | 4.9 | 6.4 |
| Liver | 6.9 | 5.7 | 7.3 | 6.2 | 8.1 | 7.2 | 9.2 | 8.7 |
| Gall bladder | 5.9 | 7.4 | 6.3 | 7.7 | 7.0 | 8.4 | 7.9 | 9.9 |
| Spleen | 14.1 | 9.1 | 14.6 | 9.3 | 15.7 | 10.3 | 16.7 | 11.4 |
| Stomach | 8.8 | 7.2 | 9.5 | 7.7 | 10.9 | 8.6 | 12.3 | 10.0 |
| Brain | 0.7 | 1.2 | 0.6 | 1.1 | 0.5 | 0.8 | 0.4 | 0.7 |
| Bladder | 0.0 | 0.0 | 0.0 | 0.0 | 0.1 | 0.1 | 0.1 | 0.1 |
| Large intestine | 2.3 | 2.5 | 2.3 | 2.5 | 2.6 | 2.7 | 2.8 | 2.8 |
| Pancreas | 5.7 | 5.8 | 6.1 | 6.3 | 6.9 | 7.4 | 7.8 | 8.8 |
| Prostate | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 |
| Adrenals | 5.7 | 5.6 | 6.2 | 6.5 | 7.3 | 8.1 | 8.5 | 10.5 |
| Testes | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 |
| Eyes | 0.6 | 0.8 | 0.6 | 0.7 | 0.4 | 0.6 | 0.3 | 0.5 |
| Small intestine | 1.9 | 1.9 | 2.0 | 2.0 | 2.3 | 2.3 | 2.5 | 2.6 |
| Ovaries | 0.1 | 0.1 | 0.1 | 0.1 | 0.1 | 0.1 | 0.1 | 0.1 |
| Uterus | 0.1 | 0.1 | 0.1 | 0.1 | 0.1 | 0.1 | 0.1 | 0.1 |
| Vagina | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 |
| Breasts | 21.9 | 17.2 | 18.9 | 13.2 | 14.6 | 8.6 | 9.5 | 4.5 |
| Heart | 8.6 | 7.2 | 8.9 | 7.4 | 9.8 | 8.1 | 9.3 | 8.1 |
| Lungs | 13.8 | 13.3 | 13.0 | 11.5 | 11.4 | 8.8 | 9.0 | 6.6 |
| Thyroid | 48.1 | 34.6 | 44.9 | 31.9 | 35.6 | 24.0 | 25.1 | 15.5 |
| Thymus | 21.9 | 19.8 | 19.6 | 17.3 | 16.9 | 13.0 | 13.1 | 9.5 |
| Esophagus | 22.7 | 20.6 | 20.6 | 17.4 | 15.6 | 12.1 | 10.7 | 8.0 |
| Bones | 6.9 | 5.7 | 6.0 | 4.6 | 4.8 | 3.3 | 4.3 | 2.9 |
| Marrow | 2.8 | 2.6 | 2.7 | 2.6 | 2.7 | 2.5 | 2.4 | 2.1 |
| Skin | 1.8 | 1.4 | 1.7 | 1.4 | 1.7 | 1.3 | 1.7 | 1.3 |