Nordquist J, Carlson J, Dougan P, Olsson S B, Salemark L
Department of Plastic and Reconstructive Surgery, University Hospital MAS, Malmö, Sweden.
J Thromb Thrombolysis. 2000 Apr;9(3):243-9. doi: 10.1023/a:1018766611751.
Thrombosis is one of the most important causes of morbidity in the medical field. Several independent in vitro studies have shown that the fibrinolytic process may be enhanced by ultrasound, but the effect of ultrasound on thrombus formation in vivo is unexplored. The present study was designed to investigate this matter.
In a blind randomized study, standardized arteriotomies and intimectomies were performed on the central arteries of the ears of 25 rabbits. The rabbits were allocated to two groups, an untreated control group and a group treated with ultrasound (10 pulses of frequency 1 MHz and intensity 1 W/cm(2) per millisecond giving an averaged intensity of 0.01 W/cm(2)). Immediately after reperfusion, patency was confirmed by a manual empty/refill test, after which blood-flow was monitored using ultrasonic flow-probes twice a minute for two hours. At two hours, patency was rechecked.
All vessels were patent at reperfusion, but only seven vessels (three control, four treated) were patent when flow-rate measurements started. At 2 h, patency-frequencies were 12/23 in the control group and 11/22 in the treated group. Flow-rate curves in patent vessels in both groups were similar. Microscopic investigation at one week showed no difference in thrombus accumulation.
Ultrasound with the above characteristics does not significantly improve patency in vivo.
血栓形成是医学领域发病的最重要原因之一。多项独立的体外研究表明，超声可能会增强纤维蛋白溶解过程，但超声对体内血栓形成的影响尚未得到研究。本研究旨在探讨这一问题。
在一项盲法随机研究中，对25只兔子耳朵的中央动脉进行标准化的动脉切开术和内膜切除术。将兔子分为两组，一组为未治疗的对照组，另一组为接受超声治疗的组（频率1MHz、强度1W/cm²，每毫秒10个脉冲，平均强度为0.01W/cm²）。再灌注后立即通过手动排空/再充盈试验确认通畅情况，之后使用超声流量探头每分钟监测血流两次，持续两小时。两小时时，重新检查通畅情况。
再灌注时所有血管均通畅，但开始测量流速时只有7条血管（3条对照组，4条治疗组）通畅。两小时时，对照组通畅频率为12/23，治疗组为11/22。两组通畅血管的流速曲线相似。一周时的显微镜检查显示血栓积聚无差异。
具有上述特征的超声在体内并不能显著改善血管通畅情况。
