Transient hepatic attenuation differences and focal liver lesions: sump effect due to primary arterial hyperperfusion.

Objective: To analyze at computed tomography (CT) examination the "sump effect," a particular type of transient hepatic attenuation differences, related primarily to an increase in arterial flow without any accompanying decrease in portal flow.

Methods: We retrospectively evaluated all biphasic upper abdomen CT examinations (1283 in 807 patients) performed from the year 2003 to the year 2006 and selected and organized those with at least 1 transient hepatic attenuation differences. Of these, we enrolled patients with lobar/multisegmental arterializations surrounding focal lesion(s), without CT portal hypoperfusion signs, in the study group.

Transient hepatic attenuation difference (THAD) in biliary duct disease.

Background: THADs are associated with a wide spectrum of hepato-biliary pathologies. The aim of this paper is to find out the role of THADs in the imaging assessment of biliary diseases. We performed a retrospective study to establish the frequency of arterial phenomena in patients with specific biliary diseases.

Transient hepatic intensity differences: part 2, Those not associated with focal lesions.

Objective: The purpose of our study was to evaluate and to show the range of appearance of transient hepatic signal intensity differences when not associated with focal lesions, and to correlate morphology, cause, and pathogenesis.

Conclusion: Hepatic arterial phenomena, visualized on MRI and CT, must be considered important signs of underlying liver disorders, which these phenomena contribute to evaluate. Accordingly, the hepatic arterial phase must always be performed on MRI as well as on CT, even if no focal lesion is expected.

Transient hepatic intensity differences: part 1, Those associated with focal lesions.

Objective: The purpose of our study was to evaluate, on MRI, transient hepatic signal intensity differences (THID) that have already been seen on CT as transient hepatic attenuation differences (THAD) and to show the range of appearance of such arterial phenomena, when associated with focal lesions, in an effort to correlate morphology, cause, and pathogenesis.

Conclusion: Hepatic arterial phenomena visualized on MRI should be known and recognized to avoid incorrect diagnoses and to improve the characterization of focal liver lesions because their shape can lead to an understanding of pathogenetic mechanisms.

[Meaning and etiopathogenesis of sectorial transient hepatic attenuation differences (THAD)].

Purpose: To examine sectoral transient hepatic attenuation differences (THAD) in an attempt to correlate semeiotics with etiopathogenesis and to deduce a possible diagnostic value.

Materials And Methods: Over a period of three years (January 1998-January 2001) we observed 130 THAD in 988 patients, and we selected 30 sectoral THAD in 18 patients (10 males and 8 females), ranging in age from 24 to 82 years (average = 63.3).