The first image shows the left lobe of the liver in an oblique sagittal plane during the late portal venous phase (contrast agent: SonoVue). Homogeneous, normal enhancement is visible throughout the liver parenchyma. The mechanical index (MI) is low which is typical for a CEUS preset (0.07).
Immediately after the flash mode is triggered a transient bright flare becomes visible, as the MI is radically increased (1.15) resulting in instantaneous destruction of microbubbles within the imaging plane.
After the flash the dramatic signal decrease is apparent.
Re-fill of the target area by the less concentrated microbubbles begins immediately, as demonstrated by the fourth image.
Nevertheless, the enhancement levels will not reach that of adjacent "non-flashed" areas which can be demonstrated by switching to a perpendicular imaging plane: the "ghost" of the flash remains visible as a hypoenhancing streak.
The sequence of events is best demonstrated by the cine loops.