Abdominal ultrasound (US) has been widely used in the evaluation of patients with schistosomiasis mansoni. It represents an important indirect method of diagnosis and classification of the disease, and it has also been used as a tool in the evaluation of therapeutic response and regression of fibrosis. We describe the case of a man in whom USshowed solid evidence of schistosomal periportal fibrosis and magnetic resonance imaging revealed that periportal signal alteration corresponded to adipose tissue which entered the liver togheter with the portal vein.Key words: schistosomiasis -Schistosoma mansoni -ultrasound -magnetic resonance imaging Abdominal ultrasound (US) has been widely used in the evaluation of patients with schistosomiasis mansoni. It represents an important indirect method of diagnosis and classification of the disease (Abdel-Latif et al. 1981, Hussain et al. 1984, Fataar et al. 1984, Cerri et al. 1984, Homeida et al. 1988a, b, Abdel-Wahab et al. 1989, PintoSilva et al. 1994, Gerspacher-Lara et al. 1998, GerspacherLara 1999, Niamey Working Group 2000, Ritcher et al. 2001. US has also been used as a tool in the evaluation of therapeutic response and regression of fibrosis in schistosomiasis (Massoud et al. 1986, Homeida et al. 1988c, Homeida et al. 1991, DoehringSchwerdtfeger et al. 1992, Boisier et al. 1998, Frenzel et al. 1999, De Jesus et al. 2000, Cota et al. 2006. Ultrasonographic examination of subjects with hepatosplenic schistosomiasis has detected a characteristic pattern of abnormalities, quite different from the aspects observed in liver cirrhosis (Homeida et al. 1988a, Abdel-Wahab et al. 1989) and in acute schistosomiasis (Barata et al. 1999, 1997. The most important finding was echogenic thickening of the walls of the portal vein and its branches. Field studies in endemic areas have shown that the sum of total thickening of three peripheral branches of the portal vein, thickening of gallbladder wall, enlargement of the left lobe of the liver, and thickening of the portal vein in its bifurcation are the best variables for ultrasonographic diagnosis of schistosomiasis mansoni (Gerspacher-Lara 1999).Magnetic resonance imaging (MRI) has been described in four cases of hepatosplenic schistosomiasis mansoni (Patel et al. 1993, Willemsen et al. 1995, Lambertucci et al. 2002, 2004 puted tomography (CT) and MRI in the evaluation of a patient with hepatosplenic schistosomiasis mansoni. The findings of the different methods were in agreement in both studies. Periportal echogenic thickening on US, suggestive of fibrosis, and low attenuation bands about the portal vessels, which markedly enhanced with contrast CT were described. MRI demonstrated the same periportal bands that were seen on liver US and CT scans. These bands showed hiperintense signal on T2-weighted sequences, and were isointense in T1-weighted sequences, with enhancement after contrast administration. The studies of Lambertucci et al. (2002Lambertucci et al. ( , 2004 evaluated patients with advanced forms of hepatosplenic schistosom...