Gastrointestinal Imaging

Alveolar Echinococcosis: MR Findings in the Liver

PURPOSE: To clarify the magnetic resonance (MR) imaging findings of alveolar echinococcosis in the liver.

MATERIALS AND METHODS: Thirty-five patients with 50 lesions histologically proven to be alveolar echinococcosis were evaluated with MR imaging. Lesions were assessed with regard to the distribution pattern of solid and cystic components and pattern of contrast material enhancement.

RESULTS: Cystic components exhibited two patterns at T2-weighted MR imaging: small round cysts and large and/or irregular cysts. Forty-eight lesions (96%) contained small round cysts. Twenty-six lesions (52%) had large and/or irregular cysts. Forty-five lesions (90%) were associated with a solid component. MR imaging characteristics were categorized into five types: multiple small round cysts without a solid component (two lesions [4%], type 1), multiple small round cysts with a solid component (20 lesions [40%], type 2), a solid component surrounding large and/or irregular cysts with multiple small rounds cysts (23 lesions [46%], type 3), a solid component without cysts (two lesions [4%], type 4), and a large cyst without a solid component (three lesions [6%], type 5). In most cases (97%), contrast enhancement was weak.

CONCLUSION: The MR findings of alveolar echinococcosis in the liver are multiple small round cysts with a weakly enhanced solid component. The cystic component can be a large and/or irregular lesion, and such lesions are depicted clearly at T2-weighted MR imaging.

© RSNA, 2003


  • 1 Choji K, Fujita N, Chen M, et al. Alveolar hydatid disease of the liver: computed tomography and transabdominal ultrasound with histopathological correlation. Clin Radiol 1992; 46:97-103. Crossref, MedlineGoogle Scholar
  • 2 Sasaki F, Ohkawa Y, Sato N, Uchino J, Hata Y. Imaging diagnosis of alveolar echinococcosis in young patients. Pediatr Radiol 1997; 27:63-66. Crossref, MedlineGoogle Scholar
  • 3 Didier D, Weiler S, Rohmer P, et al. Hepatic alveolar echinococcosis: correlative US and CT study. Radiology 1985; 154:179-186. LinkGoogle Scholar
  • 4 Czermak BV, Unsinn KM, Gotwald T, et al. Echinococcus multilocularis revisited. AJR Am J Roentgenol 2001; 176:1207-1212. Crossref, MedlineGoogle Scholar
  • 5 Gharbi HA, Hassine W, Brauner MW, Dupuch K. Ultrasound examination of the hydatic liver. Radiology 1981; 139:459-463. LinkGoogle Scholar
  • 6 Haliloglu M, Saatci I, Akhan O, Ozmen MN, Besim A. Spectrum of imaging findings in pediatric hydatid disease. AJR Am J Roentgenol 1997; 169:1627-1631. Crossref, MedlineGoogle Scholar
  • 7 Tuzun M, Hekimoglu B. Various locations of cystic and alveolar hydatid disease: CT appearances. J Comput Assist Tomogr 2001; 25:81-87. Crossref, MedlineGoogle Scholar
  • 8 Fujita N, Kishimoto R, Yoshikawa H. Magnetic resonance imaging of alveolar hydatid disease of the liver. In: Uchino J, eds. Alveolar echinococcosis: strategy for eradication of alveolar echinococcosis of the liver. Sapporo, Japan: Fujishoin, 1996; 183-187. Google Scholar
  • 9 von Sinner W, te Strake L, Clark D, Sharif H. MR imaging in hydatid disease. AJR Am J Roentgenol 1991; 157:741-745. Crossref, MedlineGoogle Scholar
  • 10 Balci NC, Tunaci A, Semelka RC, et al. Hepatic alveolar echinococcosis: MRI findings. Magn Reson Imaging 2000; 18:537-541. Crossref, MedlineGoogle Scholar
  • 11 Claudon M, Bessieres M, Regent D, et al. Alveolar echinococcosis of the liver: MR findings. J Comput Assist Tomogr 1990; 14:608-614. Crossref, MedlineGoogle Scholar
  • 12 Arakawa K. Imaging and anatomical study of echinococcosis: CT and MR imaging in alveolar hydatid disease. Nippon Igaku Hoshasen Gakkai Zasshi 1994; 54:235-244. [Japanese]. MedlineGoogle Scholar
  • 13 Choji T, Choji K, Fujita N, et al. MRI of alveolar hydatid disease of the liver: correlative study with CT and pathology. Jap J Magn Reson Med 1990; 10:209-219. [Japanese]. Google Scholar

Article History

Published in print: July 2003