MR Imaging Findings of Clonorchiasis Yong Yeon Jeong, MD1 Heoung Keun Kang, MD1 Jin Woong Kim, MD1 Woong Yoon, MD1 Tae Woong Chung, MD1 Seog Wan Ko, MD2 Index terms : Bile ducts, diseases Bile ducts, cholangitis Magnetic resonance (MR), cholangiopancreatography Bile ducts, MR Korean J Radiol 2004;5 :25-30 Received July 7, 2003; accepted after revision January 5, 2004. 1Department of Diagnostic Radiology, Chonnam National University Medical School; 2Department of Diagnostic Radiology, Namkwang Hospital, Seonam University Medical School Address reprint requests to: Yong Yeon Jeong, MD, Department of Diagnostic Radiology, Chonnam National University Medical School, 8 Hack-dong, Dong-gu, Gwang-Ju 501-757, Korea. Tel. (8262) 220-5748 Fax. (8262) 226-4380 e-mail: yjeong@chonnam.ac.kr Korean J Radiol 5(1), March 2004 Objective: The purpose of this study was to evaluate the MR spectrum and MR cholangiographic imaging findings of clonorchiasis. Materials and Methods: We reviewed 26 patients with confirmed clonorchia- sis by either stool tests (n = 24) or surgery (n = 2). MR imaging was performed on a 1.5 T system (GE Medical Systems, Milwaukee, WI) with a torso coil. Axial T1- and T2-weighted, gadolinium-enhanced dynamic images and MR cholangiogra- phy were obtained. Image analyses were used to identify abnormalities of the intrahepatic and extrahepatic bile ducts and the presence of hepatobiliary malig- nancy. All MR examinations were reviewed by the consensus of two abdominal radiologists. Results: Intrahepatic bile duct abnormalities were seen in 23 (89%) of the 26 patients. The most common finding was mild dilatation of the intrahepatic bile duct which was found in 21 (81%). “Too many intrahepatic ducts” were found in 16(62%), wall enhancement and thickening in 21 (81%) and filling defects and ductal stricture in the intrahepatic bile duct in 6 (24%) and 3 (12%) patients, respectively. Extrahepatic ductal dilation was found in 5 (19%) and 9 (35%) revealed hepatobiliary malignancy. Conclusion: MR imaging revealed various findings of clonorchiasis, including dilatation, wall enhancement, stricture of the intrahepatic ducts and filling defect within the intrahepatic bile duct. C chronic infestation of Clonorchiasis sinensis following ingestion of raw lonorchiasis is an important parasitic disease of the bile ducts caused by freshwater fish flesh in East and South-east Asia (1, 2). Clonorchiasis is one of the most frequent causes of cholangiocarcinoma and cholangitis in endemic countries, and therefore its early diagnosis is critical for the prevention of complica- tions (3 5). Several reports have described the radiological features of clonorchiasis on cholan- giography, ultrasonography and CT (6 10). MR imaging has been used in the diagno- sis of various diseases of the biliary system, and MR cholangiography (MRC) is a relatively new noninvasive type of imaging for evaluation of the extrahepatic biliary pathology (i.e. strictures, stones, and obstruction). MR cholangiography is generally comparable with endoscopic retrograde cholangiopancreatography (ERCP) for the demonstration of segmental and peripheral intrahepatic bile ducts, and may show intrahepatic ductal abnormalities in a comparable fashion to that of ERCP (11 14). To our knowledge, only one radiological report has briefly reviewed the MR findings of clonorchiasis (15). The purpose of our study was to evaluate the MR imaging and MRC findings of clonorchiasis. 25