Table 4.
Comparison of In vivo Thrombolysis Treatment Results in Porcine DVT Model
| Shock-scattering Histotripsy (Maxwell et al 2011) | Microtripsy | |
|---|---|---|
| Central Frequency | 1 MHz | 1 MHz |
| Cycles per Pulse | 5 | 1.5 |
| PRF | 1000 Hz | 100 Hz |
| P-* | ~17 MPa | ~35 MPa |
| Recanalization Success Rate | 58.3% (7 of 12) | 92.8% (13 of 14) |
| Increase in Channel Diameter** | 3.0 ± 0.8 mm | 3.3 ± 1.0 mm |
| Increase in Flow Rate | N/A | 4.74 ± 2.08 cm/s |
| Restored Flow | Less Continuous | Strong and Continuous |
| Treatment Time | ~ 5.2 min/cm | 16.6 min/cm |
| Estimated # of Pulses Delivered per Treatment | 625,000 | 180,000 |
| Increase in Free Hemoglobin*** | > 300 mg/dL | < 70 mg/dL |
| Endothelium Damage of Femoral Vein | Observed | Not Observed |
| Hemorrhage | Medium | Minor |
| Vessel Wall Perforation | No | No |
*
Estimated peak negative pressure at the target with assumptions of 2cm-thick overlaying tissue and 0.5 dB/cm/MHz acoustic attenuation.
**
Only include the treatments where recanalization was successful. 7 treatments for shock-scattering histotripsy and 13 treatments for microtripsy.
***
Free hemoglobin is an indication of the degree of hemolysis. Microtripsy caused less hemolysis than shock scattering histotripsy.