Value of contrast-enhanced magnetic resonance cholangiography in patients undergoing laparoscopic cholecystectomy

Morphologic factors of biliary trees are associated with gallstone-related biliary events

AIM: To determine the risk factors for gallstone-related biliary events.

METHODS: This retrospective cohort study evaluated magnetic resonance cholangiopancreatography images from 141 symptomatic and 39 asymptomatic gallstone patients who presented at a single tertiary hospital between January 2005 and December 2012.

RESULTS: Logistic regression analysis showed significant differences between symptomatic and asymptomatic patients with gallstones in relation to the number of gallstones, the angle between the long axis of the gallbladder and the cystic duct, and the cystic duct diameter. Multivariate analysis showed that the number of gallstones (OR = 1.27, 95%CI: 1.03-1.57; P = 0.026), the angle between the long axis of the gallbladder and the cystic duct (OR = 1.02, 95%CI: 1.00-1.03; P = 0.015), and the diameter of the cystic duct (OR = 0.819, 95%CI: 0.69-0.97; P = 0.018) were significantly associated with biliary events. The incidence of biliary events was significantly elevated in patients who had the presence of more than two gallstones, an angle of > 92° between the gallbladder and the cystic duct, and a cystic duct diameter < 6 mm.

CONCLUSION: These findings will help guide the treatment of patients with asymptomatic gallstones. Clinicians should closely monitor patients with asymptomatic gallstones who exhibit these characteristics.

The value of magnetic resonance cholangiography in the preoperative assessment of living liver donors

OBJECTIVE

The purpose of this study was to investigate the ability of magnetic resonance cholangiography (MRC) in the depiction of biliary anatomy of living liver donors by using intraoperative cholangiography (IOC) as a gold standard.

MATERIALS AND METHODS

Between 2004 and 2006, 86 potential adult-to-adult living donor liver transplantation donors had preoperative MRC at our institution. Of these, 24 potential donors were excluded due to various clinical factors. A total of 62 of these individuals were selected for liver donation and included in the study. MRC was performed on a 1.5-T scanner with breath-hold, rapid acquisition with relaxation enhancement (RARE) sequence with half-Fourier acquisition (HASTE; Siemens) and free-breathing, three-dimensional turbo spin-echo sequence with respiratory triggering. Thin- and thick-slab imaging techniques were employed with half-Fourier RARE MRC. IOC was performed in all 63 cases. The images of IOC and MRC were classified according to a modified Huang classification, independently. The results of the MRC were then compared with the IOC results.

RESULTS

IOC was used as the reference standard; a total of 43 (69.3%) liver donors were considered to have normal biliary anatomy, whereas 19 (30.7%) were considered to have variants of biliary anatomy. Compared with IOC, MRC correctly revealed biliary anatomy in 59 of 62 (95.1%) donors. The sensitivity, specificity, positive predictive value and negative predictive value of MRC in distinguishing normal and any type of variant biliary anatomy were 84.2%, 100%, 100%, and 93.4%, respectively.

CONCLUSION

MRC is an effective imaging technique for the preoperative evaluation of the biliary anatomy in living liver donors. However, MRC and IOC should be considered complementary to one another in order to avoid complications.