Table 5.
Comparison of image noise (SD) between FDM and HDM
| Ventricle | Cerebrum | ||||||
|---|---|---|---|---|---|---|---|
| FDM | HDM | P value | FDM | HDM | P value | ||
| Mean ± SD | 1 < year | 2.2 ± 0.6 | 3.0 ± 0.7 | < 0.05 | 3.0 ± 0.6 | 4.1 ± 1.0 | < 0.05 |
| 1 to < 5 years | 2.7 ± 0.6 | 3.4 ± 0.6 | < 0.05 | 3.5 ± 0.7 | 4.5 ± 0.9 | < 0.05 | |
| 5 to < 10 years | 2.5 ± 0.4 | 3.7 ± 0.8 | < 0.05 | 3.5 ± 0.6 | 4.2 ± 0.7 | < 0.05 | |
| 10 to < 15 years | 2.9 ± 0.6 | 3.5 ± 0.8 | < 0.05 | 3.2 ± 0.7 | 4.5 ± 0.6 | < 0.05 | |
| All age | 2.6 ± 0.6 | 3.4 ± 0.7 | < 0.05 | 3.3 ± 0.6 | 4.3 ± 0.8 | < 0.05 | |
| Brain stem | Cerebellum | ||||||
| FDM | HDM | P value | FDM | HDM | P value | ||
| < 1 year | 3.2 ± 0.8 | 3.8 ± 0.8 | < 0.05 | 3.0 ± 0.8 | 3.6 ± 0.8 | < 0.05 | |
| 1 to < 5 years | 3.6 ± 0.6 | 4.5 ± 0.7 | < 0.05 | 3.1 ± 0.5 | 4.3 ± 0.7 | < 0.05 | |
| 5 to < 10 years | 3.3 ± 0.6 | 4.6 ± 0.6 | < 0.05 | 3.4 ± 0.7 | 4.0 ± 0.6 | < 0.05 | |
| 10 to < 15 years | 3.7 ± 0.8 | 4.7 ± 0.9 | < 0.05 | 3.2 ± 0.5 | 4.4 ± 0.7 | < 0.05 | |
| All age | 3.5 ± 0.7 | 4.4 ± 0.8 | < 0.05 | 3.2 ± 0.7 | 4.1 ± 0.8 | < 0.05 | |
FDM full-dose method, HDM half-dose method, SD standard deviation