NONTUMOROUS ATTENUATION CHANGES ON CT ARTERIAL PORTOGRAPHY

Objective: We prospectively studied the frequency and the distribution of nontumorous attenuation changes during CT arterial portography. Ma terials and Methods: Computed tomography arterial portograms were obta ined in 67 consecutive patients. The frequency and distribution of non tumorous attenuation changes (pseudolesions, areas of hypo- or hyperpe rfusion) were analyzed and related to the size of the tumor, the vascu lar status assessed by Doppler examination, and the presence of chroni c liver disease. Results: Pseudolesions were detected in 19 patients ( 28%). They were typical in 13 cases and atypical (round shaped or loca ted in the caudate or right lobe) in 6. Segmental, lobar, or diffuse p erfusion defects were seen in 36 patients (54%). In 56% of the cases, they were adjacent to large tumors and related to compression or throm bosis of intrahepatic portal branches as demonstrated by sonographic a nd Doppler findings. Areas of hyperperfusion were detected in 14 patie nts (21%). Of these cases, eight (57%) were peritumoral hyperperfusion . In all cases, the mean diameter of the tumors was large and there wa s compression of adjacent hepatic vein as demonstrated by sonographic and Doppler findings. Conclusion: Nontumorous attenuation changes are common in CT arterial portography. Factors leading to these artifacts include size of the tumor and vascular consequences of the tumor. Sono graphic and Doppler studies may play a role in predicting these factor s.