Additional values of high-resolution gadoxetic acid-enhanced MR cholangiography for evaluating the biliary anatomy of living liver donors: Comparison with T2 -weighted MR cholangiography and conventional gadoxetic acid-enhanced MR cholangiography.

PURPOSE: To determine the incremental value of small field of view (sFOV) high-resolution (HR) gadoxetic acid-enhanced 3D T1 -weighted (W) magnetic resonance cholangiography (MRC) for evaluating the biliary anatomy of potential living donors by comparing it to T2 W-MRC.

MATERIALS AND

METHODS

In all, 73 living donor candidates underwent gadoxetic acid-enhanced MRI (3.0T) including three kinds of MRCs: 3D multislice T2 W-MRC, regular FOV (rFOV) (380 × 380mm, resolution 1.0 × 1.2 × 3.0 mm) 3D T1 W-MRC, and sFOV (256 × 208 mm, resolution 1.0 × 1.0 × 1.0 mm) HR-T1 W-MRC. Three radiologists reviewed the image sets for the visibility of segmental intrahepatic bile ducts (BDs), biliary anatomy with its confidence level, and expected number of BD openings at right hemihepatectomy.

RESULTS

Compared to T2 W-MRC alone, the combination of sFOV HR-T1 W-MRC and T2 W-MRC (sT1 W-HR set) yielded significantly improved BD visibility scores (P < 0.01) and confidence levels for biliary anatomy (P < 0.01). Compared to the rT1 W set (rFOV T1 W-MRC with T2 W MRC), the sFOV HR set showed significantly increased caudate duct visibility (P < 0.001). In the case of T2 W-MRC presenting subdiagnostic image quality, the addition of sFOV HRT1 W-MRC provided diagnostically acceptable image visibility (53.8∼90%) to all reviewers. The addition of sFOV HR-T1 W-MRC resulted in a significantly higher consistency with the operative record and expected number of BD openings than did T2 W-MRC alone (P < 0.05 in all reviewers) or rFOV set (P < 0.05 in one reviewer) with excellent interobserver agreement of both T1 W-MRC sets.

CONCLUSION

The combination of sFOV HR-T1 W-MRC and T2 W-MRC significantly improved BD visibility and confidence levels for biliary anatomy compared to T2 W-MRC alone, thereby allowing accurate biliary anatomy assessment in most patients with subdiagnostic T2 W-MRC images.

LEVEL OF EVIDENCE: 3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;47:152-159.