The contrast agent used in CEUS was SonoVue (Bracco SpA, Milan, Italy). The agent consisted of microbubbles containing sulfur hexafluoride (SF 6) encapsulated in phospholipids. The microbubbles had a mean diameter of 2.5 μm and pH values of 4.5–7.5. The SonoVue powder was thoroughly dissolved in 5 mL normal saline; then, 2.4 mL of the solution was injected into the bolus through the cubital vein.
The ultrasound devices used included Aplio500 (TOSHIBA CORPORATION, Tokyo, Japan), LOGIQ E9 GE (General Electric Company, Boston, MA, USA), EPIQ7 (Philips Electronic N.V, Amsterdam, The Netherlands), EUB-8500 (HITACHI, Tokyo, Japan), and Aixplorer (SuperSonic Imagine, Aix-en-Provence, France). The CEUS function was available on all these devices. A linear array probe was selected with a frequency of 5.0–12.0 MHz for small masses, while an abdominal convex array probe was used with a frequency of 3.0–5.0 MHz for large masses, as the linear array probe may not be fully displayed.
The ultrasound devices used included Aplio500 (TOSHIBA CORPORATION, Tokyo, Japan), LOGIQ E9 GE (General Electric Company, Boston, MA, USA), EPIQ7 (Philips Electronic N.V, Amsterdam, The Netherlands), EUB-8500 (HITACHI, Tokyo, Japan), and Aixplorer (SuperSonic Imagine, Aix-en-Provence, France). The CEUS function was available on all these devices. A linear array probe was selected with a frequency of 5.0–12.0 MHz for small masses, while an abdominal convex array probe was used with a frequency of 3.0–5.0 MHz for large masses, as the linear array probe may not be fully displayed.