PSEUDO LESIONS ON CTAP SECONDARY TO ARTERIOPORTAL SHUNTS

Purpose: To clarify the characteristics of the defects on computed tom ography (CT) during arterial portography (CTAP) due to arterio-portal shunting (APS). Method and patients: The defects in the hepatic parenc hyma on CTAP due to angiography proven APS were characterized accordin g to their configuration, size, sharpness of margins, location of the lesion in the liver, and homogeneity of the lesions. Results: Twenty f ive patients had non-tumor related APS. The shunts were single on angi ography in 15 cases and multiple in 10 cases. The APS were due to live r cirrhosis in 22 patients, and to trauma in the other three. The lesi ons were irregular in shape in nine cases, wedge shaped in six cases, and round in four cases. In three cases both wedge and round lesions w ere seen. The margins were sharp in five single defects in five cases. The rest of the lesions were judged to have unsharp margins except fo r one case in which both clear and unclear lesions were present. In 10 cases, internal enhancement of the lesions were seen on CTAP. The loc ation of the defects were central in five cases, peripheral in nine, a nd both peripheral and central in eight cases. Conclusion: The parench ymal defects due to APS were typically irregular in shape, with unshar p margins and internal enhancement. (C) Elsevier Science Inc., 1997.