Table 1.
Imaging parameters for stability and sensitivity evaluation of the contrast response measurement. Baseline parameters list the nominal, starting point scan parameters. Stability and sensitivity parameters match the baseline parameters except for the indicated changes
| Contrast response test | 9L | C1‐5 | S1‐5 |
|---|---|---|---|
| Baseline | |||
| Transmit frequency | 7 MHz | 4 MHz | 3 MHz |
| Power | 60% | 60% | 60% |
| Gain | 85 dB | 65 dB | 60 dB |
| Dynamic range | 69 dB | 84 dB | 84 dB |
| Gray map | D | D | D |
| Phantom background | 0.7 dB/cm/MHz gel | 0.7 dB/cm/MHz gel | 0.7 dB/cm/MHz gel |
| Stability | |||
| Changed gain/power | 80/60%, 85/100%, 85/30%, 90/60% | 60/60%, 65/100%, 65/30%, 70/60% | 55/60%, 60/100%, 60/30%, 65/60% |
| Changed gray map | A and J | A and J | A and J |
| Changed frequency | 9 MHz | 5 MHz | 4 MHz |
| Sensitivity | |||
| Changed dynamic range | 48 and 90 dB | 75 and 96 dB | 76 and 96 dB |