Table 2:
Measured entrance air kerma rates for a typical patient examination and for the largest FOV in fluoroscopic mode II preferred for clinical imaginga
| System | DRT | Plane | kV | Focal Spot (mm) | Measured EAKR (mGy/min) | K̄a,r Ratio |
|---|---|---|---|---|---|---|
| FD 20/20 | No | AP | 68 ± 1 | Small (0.4) | 5.1 ± 0.2 | 1.03 ± 0.12 |
| LAT | 69 ± 1 | Small (0.4) | 6.1 ± 1.0 | 1.00 ± 0.04 | ||
| FD 20/10 | Before | AP | 68 ± 1 | Small (0.4) | 4.9 ± 1.0 | 1.07 ± 0.03 |
| LAT | 72 ± 4 | Small (0.5) | 6.3 ± 3.4 | 0.97 ± 0.004 | ||
| After | AP | 68 ± 1 | Small (0.4) | 2.8 ± 0.4 | 0.96 ± 0.08 | |
| LAT | 73 ± 2 | Small (0.5) | 4.4 ± 0.6 | 1.01 ± 0.1 |
Note:—AP indicates anteroposterior; DRT, dose-reduction technology.
a
For each system, the selected kilovolt and x-ray focal spot along with its nominal size (millimeter) for each plane are summarized. For the FD 20/10 system, these values are reported before and after the installation of the DRT. The x-ray beam filtration is 0.4 mm Cu and 1 mm of Al for all systems, platforms, and planes.