Intraoperative "white test" for bile leak detection during liver resection: a video vignette

Postoperative bile leak remains a significant source of morbidity after liver resection, especially following major or complex hepatectomies. The intraoperative "white test" is a simple technique to improve detection of bile leaks through retrograde injection of a lipid emulsion into the biliary tree, enabling direct visualization of open bile ducts on the transection surface. We report its use during a minimally invasive extended left hepatectomy for colorectal liver metastases. After parenchymal transection, the white test was performed via the cystic duct stump using Intralipid (Fresenius Kabi), identifying a focal bile leak near the left pedicle stapling line, which was promptly secured. The postoperative course was uneventful, with no bile leak or liver-related complications. Follow-up imaging showed no recurrence or biloma. This case highlights the technical simplicity and high visual contrast of the white test for intraoperative bile leak detection, with the accompanying video offering added educational value beyond a written description.