Table 2.
Geometric characterization of the CT-based and landmark-based positioning strategies for both transducers. Mean values ± standard deviation are presented.
| 120-kHz transducer | 500-kHz transducer | |||
|---|---|---|---|---|
| CT-based | Landmark | CT-based | Landmark | |
| Distance between transducer center and centroid of M1 (mm) | 53.7±4.5* | 56.8±4.6* | 54.4±4.9+ | 56.8±4.6+ |
| Bone thickness along the central axis of the transducer (mm) | 2.5±0.7*^ | 3.0±1.0* | 2.8±0.6^ | 2.9±0.9 |
| Mean distance between M1 and transducer axis (mm) | 4.0 ±1.1*^ | 7.2 ±3.0* | 3.3 ±0.7+^ | 7.2±2.9+ |
indicate pairs with significant statistical difference (p<0.05)