The "chicken-claw sign": A novel landmark for bona fide minimally invasive anatomic liver resection.

Abstract

Anatomic liver resection requires precise transection along the intersegmental/sectional plane. The conventional approach relies on ischemic demarcation and hepatic vein landmarks, which do not always align with true anatomic boundaries. In this study, the "chicken-claw sign" was evaluated as a novel landmark that identifies the intersegmental/sectional plane by recognizing the termination of Glissonean tributaries, enabling the surgeons to achieve bona fide anatomic liver resection. It was hypothesized that precise transection aligning with true anatomic boundaries of the liver parenchyma should virtually never necessitate the dissection of Glissonean tributaries. The surgical outcomes of patients who underwent laparoscopic right/left hemihepatectomy using the chicken-claw sign (n = 13) were retrospectively compared with those of individuals using the conventional approach (n = 8). The primary endpoint was the number of dissected Glissonean tributaries, whereas secondary endpoints included liver resection time and speed, estimated blood loss, and the incidence of bile leakage. The implementation of the chicken-claw sign significantly reduced the number of dissected Glissonean tributaries, particularly in the deep liver parenchyma, compared with the conventional approach. In left hemihepatectomy, liver resection time was significantly shorter (P = .007), whereas in right hemihepatectomy, both resection time (P = .019) and speed (P = .035) significantly improved. Estimated blood loss was comparable between the groups, and no bile leakage was observed in the entire cohort. The chicken-claw sign minimizes the dissection of Glissonean tributaries, enabling the surgeons to achieve bona fide minimally invasive anatomic liver resection, potentially leaving no ischemia in the future liver remnant.