Right hemihepatectomy preserving the fluorescently visible paracaval portion of the caudate lobe

The paracaval portion (PC) of the caudate lobe is a small area of the liver located in front of the inferior vena cava. Conventional right hemihepatectomy (RH) along the Rex-Cantlie line involves resection of not only the anterior and posterior sections but also the PC behind the middle hepatic vein (MHV). However, to preserve the future liver remnant volume as much as possible, PC-preserving RH may be beneficial in selected patients. We injected an indocyanine green (ICG) solution in the PC portal branch under intraoperative ultrasonography (IOUS) guidance and performed an RH preserving the fluorescently visible PC in a patient with liver metastasis. The patient was a 47-yearold male with a 24 x10 cm metastatic hepatic tumor from sigmoid colon cancer. CT volumetry revealed that the left hemiliver excluding the caudate lobe was 55%, and the caudate lobe was 5.3%. Before hepatic transection, the ICG solution was injected into the PC portal branch under IOUS guidance. During hepatic transection, the PC was identified as a fluorescent area behind the MHV using a near-infrared imaging system. Thus, the anatomical right-side boundary of the caudate lobe was clearly found. Following RH, the PC was preserved as a fluorescently visible area. The patient had an uneventful recovery. RH preserving the fluorescently visible PC of the liver is a feasible procedure.