Regarding patient history, features on CT images are typical for pyogenic hepatic abscesses.
The cluster sign refers to an aggregation of multiple low attenuation liver lesions in a localized area to form a solitary larger abscess cavity suggesting pyogenic hepatic abscesses.1
The double target sign is also a characteristic imaging feature of hepatic abscess where the abscess membrane demonstrates early contrast enhancement, in contrast to the outer rim, which only enhances the delayed phase due to the edema of the liver parenchyma.2