Ultrasound In Medicine And Biology
The purpose of this study was to examine the effects of applied mechanical index, incident angle, attenuation and thrombus age on the ability of 2-D vs. 3-D diagnostic ultrasound and microbubbles to dissolve thrombi. A total of 180 occlusive porcine arterial thrombi of varying age (3 or 6 h) were examined in a flow system. A tissue-mimicking phantom of varying thickness (5 to 10 cm) was placed over the thrombosed vessel and the 2-D or 3-D diagnostic transducer aligned with the thrombosed vessel using a positioning system. Diluted lipid-encapsulated microbubbles were infused during ultrasound application. Percent thrombus dissolution (%TD) was calculated by comparison of clot mass before and after treatment. Both 2-D and 3-D-guided ultrasound increased %TD compared with microbubbles alone, but %TD achieved with 6-h-old thrombi was significantly less than 3-h-old thrombi. Thrombus dissolution was achieved at 10 cm tissue-mimicking depths, even without inertial cavitation. In conclusion, diagnostic 2-D or 3-D ultrasound can dissolve thrombi with intravenous nontargeted microbubbles, even at tissue attenuation distances of up to 10 cm. This treatment modality is less effective, however, for older aged thrombi. (E-mail: email@example.com) (C) 2011 World Federation for Ultrasound in Medicine & Biology.
F. Xie, E. Carr Everbach, S. J. Gao, L. K. Drvol, W. T. Shi, F. Vignon, J. E. Powers, J. Lof, and T. R. Porter.
"Effects Of Attenuation And Thrombus Age On The Success Of Ultrasound And Microbubble-Mediated Thrombus Dissolution".
Ultrasound In Medicine And Biology.