Noninvasive thrombolysis using histotripsy beyond the intrinsic threshold (microtripsy)

摘要: Histotripsy has been investigated as a noninvasive, drug-free, image-guided thrombolysis method that fractionates blood clots using acoustic cavitation alone. In previous histotripsy-mediated studies, clouds were generated multi-cycle pulses and tended to form on vessel wall. To avoid potential cavitational damage the wall, new histotripsy approach, termed microtripsy, recently discovered in which is via an intrinsic-threshold mechanism single-cycle pulses. We hypothesize microtripsy can generate confine lumen without contacting results recanalization within clot potentially eliminating damage. test our hypothesis, was for vitro flow model. Clots formed inside phantom (6.5 mm inner diameter) line with system. Microtripsy applied by 1-MHz transducer at pulse repetition frequency of 50 Hz peak negative pressure (P−) 30 MPa or 36 MPa. create channel through clot, focus scanned interval 0.3 0.7 mm. The treated 3-D-scanned 20-MHz ultrasound probe quantify channels. Restored rates measured debris particles from treatments analyzed. all treatments, cloud consistently center After each treatment, successfully completely confined clot. channels had diameter up 60% diameter, restored 500 mL/min. small more than 99.9% < 10 μm largest 153 um. Each (2 cm long) recanalized 7 min. size increased higher P− significantly larger scan those this study show fast, precise, effective recanalization, minimizing risks embolism.