Using the IOUS, the tumor and the level targeted for compression are identified. Than, under the IOUS guidance, the surgeon compresses bilaterally the liver at the targeted position resulting in the compression of the portal pedicle feeding the tumor previously identified. This maneuver is constantly monitored in real-time just using the same microconvex probe, and it is maintained until the surface of the targeted liver area begins to discolor, at that time the first assistant marks the discolored area with the electrocautery, and the compression is released. Once the area is demarcated, liver dissection is started under intermittent Pringle's maneuver.