Table 1.
CFs for 123I with the LEHR and ME collimator and 131I with the HE collimator, in cps/MBq, for the four CF
source geometries
| VOI diameter | 123I LEHR (cps/MBq) | 123I ME (cps/MBq) | 131I HE (cps/MBq) | |
|---|---|---|---|---|
| 1 | CFcylinder | 89.3 | 119.0 | 27.7 |
| 2 | CFcylinder | 88.4 | 115.6 | 26.8 |
| CFwater | 84.4 | 118.2 | 27.6 | |
| CFair | 82.4 | 116.4 | 27.2 | |
| CFpoint | 84.1 | 115.5 | 27.8 | |
| Average ± SD | 84.8 ± 2.5 | 116.4 ± 1.3 | 27.4 ± 0.4 | |
| Relative SD (%) | 2.9 | 1.1 | 1.5 | |
| 3 | CFcylinder | 100.4 | 118.9 | 28.6 |
| CFwater | 102.2 | 120.2 | 29.1 | |
| CFair | 98.4 | 117.7 | 29.4 | |
| CFpoint | 102.4 | 118.7 | 31.7 | |
| Average ± SD | 100.9 ± 1.9 | 118.9 ± 1.0 | 29.7 ± 1.4 | |
| Relative SD (%) | 1.9 | 0.8 | 4.7 | |
VOI diameters were defined as (1) less than the physical source diameter, (2) equal to the physical source diameter plus a 3-cm margin and (3) equal to the physical size of the detector