CHAPTER 9 Liver resection (left lateral sectionectomy)
Step 1. Surgical anatomy
♦ Laparoscopic removal of the left lateral section of the liver can be very straightforward. For most surgeons, this will be their first “major” liver resection. However, there is still a real risk of disaster. Because of this combination of an easy procedure and intraoperative complications that are potentially life threatening, it is imperative that the surgeon understands the anatomy and instrumentation. Skill and experience with both open liver surgery and advanced laparoscopy remain essential.
♦ The left lateral section of the liver (formerly called the left lobe, now segments 2 and 3) is defined as the parenchyma to the left side of the falciform ligament. This ligament fans out over the surface of the left lateral section as Glissons capsule and condenses posteriorly as the left triangular ligament, attaching the liver to the undersurface of the diaphragm.
♦ The round ligament, or ligamentum teres, representing the usually obliterated umbilical vein, runs in the free edge of the falciform ligament, and enters the liver anterior to a variably thick bridge of liver tissue linking segments 3 and 4b. The caudate lobe lies posteriorly, separated from the left lateral section by the hepatogastric ligament or lesser omentum.
♦ The branching inflow to the left hemiliver lies just deep to the entry of the round ligament into the liver. Here the left portal triad of hepatic artery, bile duct, and portal vein divides with branching to segments 2 and 3 on the left and segment 4 on the right.
♦ The left lateral section is drained by the left hepatic vein, which usually joins with the middle vein before entering the vena cava. The left vein has a variable extrahepatic course, but its left side can be exposed by mobilizing the left lateral section.
Step 2. Preoperative considerations
Patient preparation
♦ Liver resection should always be undertaken for a valid reason, whether open or laparoscopic.
♦ Tumors are removed because of known malignancy, uncertain diagnosis, or symptoms.
♦ Tumors must lie well clear of the line of transection (i.e., the line of the falciform ligament).
♦ Good preoperative imaging with multiphase computed tomography (CT) or magnetic resonance imaging (MRI) is essential. This is the one liver operation where intraoperative ultrasound is not always essential, because of the clear sectional definition by the falciform ligament.
♦ Resection will be much easier in a healthy, slim, nonsteatotic liver.
♦ Enlarged fatty livers can be greatly improved by placing the patient on a high-protein, very low calorie diet for 2 weeks.
♦ The surgeon must understand the principles of open liver surgery and have skills in advanced laparoscopic surgery, such as suturing.