Prolonged intravenous indocyanine green visualization by temporary pulmonary vein clamping: real-time intraoperative fluorescence image guide for thoracoscopic anatomical segmentectomy.

The real-time endoscopic colour and fluorescence-merged imaging system, using intravenous injection of indocyanine green (ICG), allows a clear surgical view, which facilitates identification of the pulmonary inter-segmental plane in thoracoscopic surgery. However, the staining time is too short to mark and cut the intersegmental plane, because the mean washout time of ICG is only a few minutes in the clinical setting. To overcome this limitation, we have developed a new technique for prolongation of ICG staining time. The technique consists of 2 simple steps. First, we cut the targeted segmental artery, vein and bronchus. Second, ICG is injected intravenously, followed by temporary clamping of the pulmonary vein of entire lobe, including the segments. Our technique may not only offer prolonged washout time for marking the surface of the lung but also facilitate identification of precise intersegmental plane to be cut.