Dynamic CT features of hepatic abscesses.

Abstract

Forty hepatic abscesses were examined with dynamic computed tomography (CT). A "double target sign," consisting of a hypodense central area surrounded by first a hyperdense ring and then a hypodense zone, seems to be highly suggestive of abscess formation. In 12 cases, the hepatic parenchyma surrounding the lesion demonstrated transient hyperdensity after contrast injection, possibly due to localized hepatic venous obstruction secondary to acute hepatic inflammation. This is similar to the appearance of an arterioportal fistula.

Pyogenic hepatic abscesses: MRI findings on T1- and T2-weighted and serial gadolinium-enhanced gradient-echo images

“…5). Perilesional edema, described as a ''double target sign,'' has been reported to be a characteristic feature of abscesses on CT (12). This has also been reported in previous studies describing the MR appearances of hepatic abscesses (4,6).…”

CT of small pyogenic hepatic abscesses: the cluster sign

“…This was noted in 30% of the pyogenic abscesses in his series [7]. In that same report, Mathieu et al described two patients who had pyogenic hepatic microabscesses (i.e., <2 cm) caused by staphylococcal infection [7]. On CT, the small abscesses showed a miliary pattern characterized by widely disseminated, hypodense lesions scattered throughout the liver.…”

“…Numerous authors have documented the variable CT appearance of hepatic pyogenic abscesses [6][7][8][9]. This ranges from a relatively spherical, unilocular cavity to a highly irregular multiseptated configuration.…”

“…On dynamic bolus CT, Mathieu at al. [7] noted a double-target sign consisting of a hypodense central area surrounded by a hyperdense ring and then a hypodense zone. This was noted in 30% of the pyogenic abscesses in his series [7].…”

“…[7] noted a double-target sign consisting of a hypodense central area surrounded by a hyperdense ring and then a hypodense zone. This was noted in 30% of the pyogenic abscesses in his series [7]. In that same report, Mathieu et al described two patients who had pyogenic hepatic microabscesses (i.e., <2 cm) caused by staphylococcal infection [7].…”