[High-frequency sonographic analysis of postoperative blood flow properties after microvascular anastomoses]

Examination of blood flow characteristics using high frequency ultrasonic waves, has shown that in the region of the microvascular anastomosis, even in successfully replanted digits, there is turbulent flow. If this turbulence increases in the first 30 minutes following release of the clamps, vascular occlusion may be expected. In order to monitor the blood flow characteristics during the post-operative period, a high frequency ultrasonic measuring device has been developed which assisted by computer detects the spectrum analysis of the shift frequency delta f proportional to the erythrocyte velocity. This data is presented instantaneously on a monitor and shows fine changes in the flow characteristics permitting early intervention.