Masahiro Kitami, Presenter: Nothing to Disclose

Kei Takase MD, Abstract Co-Author: Nothing to Disclose

Kazuhiro Majima MD, Abstract Co-Author: Nothing to Disclose

Masahiro Tsuboi MD, Abstract Co-Author: Nothing to Disclose

Haruo Saito MD, Abstract Co-Author: Nothing to Disclose

Takayuki Yamada MD, Abstract Co-Author: Nothing to Disclose

Shuichi Higano MD, PhD, Abstract Co-Author: Nothing to Disclose

Shoki Takahashi MD, Abstract Co-Author: Nothing to Disclose

et al, Abstract Co-Author: Nothing to Disclose

Biliary variations are classified into two categories: confluence pattern variations and running course variations. The running course variation in left lobe is the infraportal left lateral segmental duct, which is defined as the duct running caudally to umbilical portion of portal vein. The aim of this study was to examine whether this running course variation was associated with confluence patterns.

We retrospectively analyzed the data of 500 patients who underwent CT cholangiography. Before (or after) 2001.8, with 4(or 8)-detector row CT, scans were obtained with the following parameters: 0.5 s/rotation, 2 (or 1) mm collimation, 14 mm/s table speed [helical pitch 3.5 (or 7)], tube current of 120 Kv/300 mA. Axial slices were reconstructed with slices of 2 (or 1)-mm thickness at 1 (0.5)-mm intervals. As a biliary contrast agent, 100 mL of meglumine iotroxate were administered over 30 min, before 1 hour of scanning. The confluence pattern of the bile duct and its relationship with the portal vein were evaluated using paging method on the workstation.

The confluence patterns in left lobe were classified as types A-D: type A, B4 drains into the common stem (B2+B3) (n=337, 67.4%); type B, triple confluence of B2, B3, and B4 (n=44, 8.8%); type C, B2 drains into the common stem (B3+B4) (n=105, 21.0%); type D, other patterns (n=14, 2.8%). We found the infraportal left lateral segmental ducts in 34 patients (6.8%). Frequency of the infraportal left lateral segmental ducts in type A, B, C, D was 3.9% (13/337), 4.5% (2/44), 16.2% (17/105), and 14.3% (2/14), respectively. The frequency of the infraportal left lateral segmental ducts was significantly higher in type C than in other types (16.2% vs. 4.3%, p<0.05).

Frequency of the running course variation in left lobe was significantly associated with confluence patterns.

Kitami, M, Takase, K, Majima, K, Tsuboi, M, Saito, H, Yamada, T, Higano, S, Takahashi, S, et al, , The Running Course Variation of Bile Ducts in Left Lobe Associated with Confluence Patterns: Analysis of 500 Patients Using MDCT Cholangiography.  Radiological Society of North America 2005 Scientific Assembly and Annual Meeting, November 27 - December 2, 2005 ,Chicago IL. http://archive.rsna.org/2005/4407348.html