Table 3 Image noise and radiation dose at different tube voltages in the case of CNR at 14
Tube voltage (kVp) | Tube current (mA) | Surface dose (mGy) | Center dose (mGy) | Measurd image noise (HU) |
|---|---|---|---|---|
New born | ||||
FBP | ||||
80 | 20 | 0.6 | 0.4 | 37 |
100 | 15 | 0.6 | 0.6 | 30 |
120 | 15 | 0.9 | 0.9 | 25 |
IR | ||||
80 | 20 | 0.6 | 0.5 | 37 |
100 | 15 | 0.7 | 0.6 | 30 |
120 | 15 | 0.9 | 0.9 | 25 |
1 year old | ||||
FBP | ||||
80 | 45 | 1.1 | 0.9 | 35 |
100 | 30 | 1.3 | 1.1 | 29 |
120 | 25 | 1.5 | 1.5 | 25 |
IR | ||||
80 | 40 | 0.9 | 0.7 | 37 |
100 | 25 | 1.1 | 1.0 | 30 |
120 | 20 | 1.4 | 1.2 | 25 |