Skip to main content

Table 2 Comparison between CFs calculated from acquisitions NEMA Cal.1 and NEMA Val. for comparable sphere–background activity ratios (SBARs)

From: Towards accurate 177Lu SPECT activity quantification and standardization using lesion-to-background voxel ratio

Sphere volume (VOI volume) [cc]

Phantom NEMA Cal. 1 acquisition

Phantom NEMA Val. acquisition

CF difference error (%) between NEMA Cal 1. and NEMA Val.

CF [cps/MBq]

SBAR

CF [cps/MBq]

SBAR

26.52 (22.7 cc)

3.92

15.91

4.06

15.28

3.44

11.49 (10.3 cc)

3.19

15.91

2.96

15.28

7.21

5.71 (6.36 cc)

2.64

15.91

1.84

15.28

30.30

  1. CF, Calibration factor; SBAR, Sphere-to-background counts/activity ratio