Common SPECT Acquisition and Reconstruction Parameters
| Parameter | Conventional SPECT | IQ•SPECT |
| Reconstruction algorithm | Filtered backprojection | OSCGM |
| Collimator | LEHR | SMARTZOOM |
| Energy window | 140 keV ± 7.5% | 140 keV ± 7.5% |
| Number of projections | 60 views (30 per detector) | 34 views (17 per detector) |
| Rotation range | 360° | 208° |
| Acquisition time (min) | 20 (35 s per projection) | 5 (9 s per projection) |
| Magnification | ×1.45 | ×1.00 |
| Rotation radius (cm) | 24–25 | 28 |
| Number of iterations | QGS: 30, QPS: 10 | |
| Number of subsets | QGS: 1, QPS: 3 | |
| Updates | 30 | |
| Gaussian filter (mm) | 9.6 | |
| Butterworth filter (cycles/cm) | QGS: 0.39, QPS: 0.52 | |
| Matrix | 64 × 64 | 128 × 128 |
| Pixel size (mm) | 6.6 | 4.8 |
LEHR = low-energy high-resolution; OSCGM = ordered-subset conjugate gradient minimization.