Ultrasound Imaging with SonoVue: Low Mechanical Index Real-Time Imaging

Abstract

Ultrasound contrast specific imaging was improved in the last years by the introduction of a wealth of novel techniques, exploiting the nonlinear response of microbubble contrast agents. This included a number of techniques based on transmission of alternately phased positive and negative pulses ( 1 Bauer A Hauff P Lazenby J et al. Wideband harmonic imaging: a novel contrast ultrasound imaging technique. Eur Radiol. 1999; 9: S364-S367 Crossref PubMed Google Scholar , 3 Burns PN Wilson SR Simpson DH Pulse inversion imaging of liver blood flow: improved method for characterizing focal masses with microbubble contrast. Invest Radiol. 2000; 35: 58-71 Crossref PubMed Scopus (326) Google Scholar ) (Phase Inversion, Pulse Inversion, Power Pulse Inversion, Wideband harmonic, Coherent Contrast Imaging) as well as techniques based on alternating transmit power (Power Modulation, B Flow) and using higher harmonics ( 2 Bouakaz A Frigstad S Ten Cate FJ de Jong N Super harmonic imaging: a new imaging technique for improved contrast detection. Ultrasound Med Biol. 2002; 28: 59-68 Abstract Full Text Full Text PDF PubMed Scopus (192) Google Scholar ) (Ultraharmonic Imaging). Other techniques are based on the destruction of microbubbles (Agent Destruction Imaging) or can be used to image microbubbles in this way (power/Color Doppler -Loss of correlation) ( 6 Schlachetzki F Hoelscher T Dorenbeck U et al. Sonographic parenchymal and brain perfusion imaging: preliminary results in four patients following decompressive surgery for malignant middle cerebral artery infarct. Ultrasound Med Biol. 2001; 27: 21-31 Abstract Full Text Full Text PDF PubMed Scopus (27) Google Scholar ) and therefore are limited to a relatively high mechanical index. The destructive techniques are further limited to low framerate or triggered imaging ( 5 Masugata H Lafitte S Peters B Strachan GM DeMaria AN Comparison of real-time and intermittent triggered myocardial contrast echocardiography for quantification of coronary stenosis severity and transmural perfusion gradient. Circulation. 2001; 104: 1550-1556 Crossref PubMed Scopus (63) Google Scholar ), thereby losing one of the key advantages of ultrasound: its realtime capability.