TABLE 1

Variability in Circumferential Count Profiles of Normal-Phantom Short-Axis SPECT Slices

Phantom positionStraight orientationAngled orientation
180°← P →360°180°← P →360°
Center4.2 ± 0.1NS4.4 ± 0.25.9 ± 0.5*NS5.3 ± 0.6
5-cm off-center5.9 ± 0.2<0.0014.7 ± 0.27.2 ± 0.4†<0.0015.0 ± 0.6
10-cm off-center9.1 ± 0.5<0.0014.2 ± 0.17.9 ± 0.2<0.0014.4 ± 0.4
15-cm off-center10.8 ± 0.1<0.0014.6 ± 0.510.3 ± 0.5<0.0015.4 ± 0.4

  • ↵* P < 0.01, compared with center/180°/straight.

  • ↵† P < 0.01, compared with 5 cm/180°/straight.

  • NS = not statistically significant.

    Variability data are mean percentage ± SEM for apical, mid-ventricle, and basal short-axis circumferential profiles and for 3 repeated acquisitions.