Heterogeneity of subvesical ducts or the ducts of Luschka: A study using drip-infusion cholangiography-computed tomography in patients and cadaver specimens

The objective of this study was to examine the heterogeneity of the subvesical duct or the ducts of Luschka as well as the reliability of drip-infusion cholangiography with computed tomography (DIC-CT) for their identification. DIC-CT was used in 277 consecutive patients (135 men, 142 women) and for the dissection and histologic study of 10 cadaver livers. We found 32 subvesical ducts in 28 (10.1%) of 277 patients. Irrespective of whether the terminals were extra- or intraparenchymal, the subvesical ducts often (17/32 ducts, 15/28 patients) drained into a sub-segmental duct of S5 or S4. Notably, some displayed an "intermediate" course along the gallbladder fossa with an intraparenchymal origin and terminated at S5. Such ducts tended to be seen in the elderly. Another 15 ducts drained into a thick, centrally located duct, such as the right sectorial or hepatic duct. The anatomic study demonstrated that the subvesical duct likely included the cystic vein-concomitant duct. A major type of subvesical duct, characterized by an intermediate course along its bed, appeared to result from degenerative exposure of a peripheral duct with aging. The subvesical duct draining into the thick duct included both a "daughter branch," such as seen in the lung, and the so-called anomaly. Such ducts can be demonstrated with DIC-CT, but the incidence might be limited. However, the cystic vein/concomitant duct was difficult to identify radiologically. Consequently, although presurgical radiology is useful for avoiding bile leakage after laparoscopic cholecystectomy, surgeons should be aware of its limitations.