Could diffusion-weighted imaging detect injured bile ducts of ischemic-type biliary lesions after orthotopic liver transplantation?

OBJECTIVE

The purpose of this article is to discuss whether diffusion-weighted imaging (DWI) shows new findings of injured bile ducts in patients with ischemic-type biliary lesions (ITBL) after orthotopic liver transplantation.

SUBJECTS AND METHODS

Thirty-five transplant recipients with ITBL (ITBL group), 20 recipients without biliary abnormalities on MRCP (control group), and 20 volunteers who did not undergo liver transplantation (healthy group) underwent MRI, MRCP, and DWI examinations.

RESULTS

Twenty-nine ITBL patients showed hyperintensity of bile ducts on DWI (82.9%, 29/35). However, only one case in the control group and no cases in the healthy group showed hyperintensity. The difference in the signal change of bile ducts on DWI between the ITBL and control groups was significant (p<0.001). The high accuracy of MRCP and DWI were 96.4% (53/55) and 87.3 (48/55), respectively. In the ITBL group, two early ITBL patients showed "normality" of bile ducts on MRCP but hyperintensity of small bile ducts on DWI, except thirty-three patients showed irregular stenosis and dilatation of bile ducts on MRCP (94.3%, 33/35).

CONCLUSION

MRCP is a noninvasive first-choice for clinical diagnosis of ITBL, mainly relying on morphologic abnormality of bile ducts. Hyperintensity of the bile ducts with ITBL patients on DWI might offer a method of noninvasively and sensitively detecting injured bile ducts, especially for early injuries, and may be helpful in detecting etiologic information of ITBL and as an effective supplement to MRCP in ITBL.