Intrahepatic portosystemic venous shunts: Spectrum of CT findings in external and internal subtypes

Purpose: The purpose of this work was to survey the spectrum of CT findings in intrahepatic portosystemic venous shunts (IPSVSs). Method: One thousand consecutive liver CT scans examined with an enhanced h elical technique were retrospectively reviewed on workstation to find IPSVS s, Results: IPSVSs were noted in 37 patients and divided into two subtypes acc ording to the location of the communicating systemic vein, either outside ( external type, n = 34) or within (n = 4) the liver tone patient had both in ternal and external types). All the external-type shunts were noted in case s with portal hypertension (n = 34. Most shunts (n = 30) ran through segmen t 4 and/or 3 and came out near the falciform ligament, but five shunts were noted in segment ? communicating either with the systemic vein (n = 3) or probably with an enlarged left gastric vein (n = 2). Solitary portohepatic venous shunts (internal type) were noted in three cases with (n = 2) or wit hout(n = l)aneurysmal dilatation and many portohepatic venous shunts in ano ther patient. Conclusion: IPSVSs of the external type were far common than those of the i nternal type, always associated with increased pressure of the portal syste m and in specific sites probably lacking the hepatic capsule.