Robotic Left Hepatectomy using Indocyanine Green Fluorescence Imaging for an Intrahepatic Complex Biliary Cyst

Robotic left hepatectomy using indocyanine green fluorescence imaging for an intrahepatic complex biliary cyst. This case involves a 68-year-old woman who had elevated liver enzymes during a routine checkup without any clinical symptoms. An abdominal ultrasound of the liver revealed intrahepatic dilatation of the biliary ducts confined to the left hemi liver without a clear lesion.

Further diagnostic examinations, including an abdominal CT, MRI scan, and MRCP showed a large complex cystic lesion of 40 millimeters on the border of segment 4A and 4B in continuity with the biliary tree with intrahepatic dilatation of biliary ducts in the left lobe. The patient was diagnosed with an intrahepatic large complex biliary cyst and was recommended for a robotic left hepatectomy. Four eight millimeter trocars were placed above the umbilicus and one 12 millimeter laparoscopic assisted trocar is introduced for the bedside surgeon on the right side of the umbilicus.

The bedside surgeon must be able to reach the transection area for suctioning, compression, clipping, and stapling without difficulty. The distance between the four ventral trocars is approximately eight centimeters. The first step is the mobilization of the left lobe, starting with the division of the round and fulcrum ligaments using the robotic cautery hook and vessel sealer.

The mobilization continues with the division of the left coronary and triangular ligaments. It is important not to injure the left hepatic vein and branches of the phrenic vein which is draining into the left hepatic vein. Open the triangular ligament using the robotic cautery hook or vessel sealer all the way towards the origin of the left hepatic vein.

The dissection is completed until the origin of the left hepatic vein is reached. The lesser momentum is visualized by lifting the inferior aspect of the liver cranially. The lesser momentum is then dissected using a vessel sealer.

If an aberrant left hepatic artery is present, ligate using robotic cautery hook or vessel sealer. The hilar dissection starts with the identification of the proper and left hepatic artery. The left hepatic artery is dissected and isolated using both the cautery hook and bipolar forceps.

After visualizing the left hepatic artery, the procedure continues with the identification and dissection of the right hepatic artery to make sure it is preserved. Once the left and right hepatic artery are visualized and dissected clearly, the left portal vein is carefully dissected and isolated. In this phase, indocyanine green fluorescence imaging is used several times to identify the exact localization and trajectory of the left bile duct with respect to the left portal vein.

The procedure continues with a cholecystectomy. First, the cystic duct and artery are dissected and isolated to achieve the critical view of safety, also known as the Calot's triangle. Both cystic duct and artery are then clipped using Hem-o-lok clips and are divided with robotic scissors.

Second, the gallbladder is dissected circumferentially off the liver using a cautery hook. Pringle loop is prepared by passing a vessel loop around the hepatoduodenal ligament. During this procedure, the Pringle maneuver was not applied.

An intraoperative ultrasound is essential during robotic liver surgery to confirm the localization, borders, and depth of the lesion. ICG fluorescence imaging is used again to confirm the trajectory of the right and left hepatic duct before heading to the arterial and venous hilar transection. First, the left hepatic artery is carefully clipped and divided.

The second step focuses on the left portal vein. The Maryland bipolar forceps is ideal in this phase to pass the vessel loop easily around the left portal vein. The next step is to clip and divide the left portal vein between Hem-o-lok clips.

Important to note that in this phase, the left hepatic duct is not divided yet to ensure no injury to the right hepatic duct. The parenchymal transection starts with a visualization of the ischemia line on the liver surface. The ischemia line should overlap the Cantlie's line since the aim is to perform an anatomical left hepatectomy.

Based on ischemia line, the transection line is marked using the cautery hook. The superficial part of the transection is performed mainly with the cautery hook til a depth of one centimeter parenchyma is reached. For a deeper parenchyma, the vessel sealer, the cautery spatula, and the bipolar cautery using Maryland forceps are used.

Intrahepatic vascular and biliary structures are controlled with the vessel sealer as well. Any small bleeding is controlled using the cautery spatula or bipolar forceps. Here, the left side of the middle hepatic vein can be visualized.

The transection continues until the left hepatic vein is reached. Before completing the transection phase, the surgeon moves back to the hilum to focus on the left hepatic duct. ICG fluorescence imaging is activated to confirm exact trajectory, size, and localization of the left hepatic duct before transection.

After this, the left hepatic duct is carefully dissected using the Maryland bipolar forceps. At last, clips are placed and the left hepatic duct is divided. The procedure ends with the division of the left hepatic vein.

A vessel loop is passed around the remaining liver parenchyma and left hepatic vein for the hanging maneuver. This allows retraction of the right lobe of the liver towards the right side amputation on the remaining liver parenchyma and left hepatic vein to be able to get a better vision and grip on the left hepatic vein. The left hepatic vein is then divided using a stapler.

When the left hepatectomy is complete, the specimen is taken out in a bag through a Pfannenstiel incision. The total operative time was 190 minutes with an estimated blood loss of 10 CC.The postoperative course was uncomplicated and the patient was discharged after four days. Histopathological examination revealed a large complex cyst of 31 millimeters without any suspicion for malignancy.

This manuscript provides the detailed steps of robotic left hepatectomy as performed at Amsterdam UMC. It shows that a robotic left hepatectomy is technically demanding, but a feasible procedure. ICG fluorescence imaging can be helpful in delineating biliary cyst and bile duct anatomy.