Search results for "Mechanical index"
showing 3 items of 3 documents
Heterogeneous delayed enhancement of hepatic parenchyma after intravenous infusion of sonographic contrast agent: a new hypothesis
2007
Purpose. The aim of this paper was to report a heterogeneous latephase hepatic enhancement pattern observed after administration of a sonographic contrast agent and to present an aetiological hypothesis for the phenomenon. Materials and methods. A total of 1,729 (1,012 women and 717 men; age range 28–82; mean age 51) patients underwent contrastenhanced sonography of the liver. The examination was performed with a low mechanical index (MI <0.09) after injection of sulphur-hexafluoride-filled microbubbles, using different fonographic equipment and different contrast-specific algorithms. Results. Heterogeneous delayed liver enhancement was observed in six patients in the late phase (180 s), wi…
Ultrastructural biologic effects of sonography with pulse inversion and microbubble contrast in rabbit liver
2005
Purpose This prospective study was conducted to evaluate the biologic effects of microbubble destruction with pulse-inversion harmonic imaging on rabbit liver parenchyma. Methods The livers of 6 albino rabbits were examined sonographically by a single investigator. Three rabbits underwent contrast-enhanced sonography, with scanning starting 5 seconds after injection by using pulse-inversion harmonic imaging with a mechanical index of 1.2. Four time-triggered images were recorded at a rate of 1 frame every 2 seconds. For comparison, 3 control rabbits had pulse-inversion harmonic imaging with a mechanical index of 1.2 only, without contrast medium. Immediately after sonography, the animals we…
Assessment of systolic left ventricular function: a multi-centre comparison of cineventriculography, cardiac magnetic resonance imaging, unenhanced a…
2005
Aims To assess the agreement of left ventricular ejection fraction (LVEF) determinations from unenhanced echocardiography, contrast-enhanced echocardiography, magnetic resonance imaging (MRI), and cineventriculography as well as the inter-observer agreement for each method. Methods and results In 120 patients, with evenly distributed EF-groups (G 55, 35-55, L 35%), cineventriculography, unenhanced echocardiography with second harmonic imaging, and contrast echocardiography at tow mechanical index with iv administration of SonoVueR were performed. In addition, cardiac MRI at 1.5T using a steady-state free precession sequence was performed in a subset of 55 patients. On-site, and two blinded …