The greatest technical challenge of laparoscopic liver resection is the control and management of bleeding. However, with the application of advanced equipment such as ultrasound knife and Ligasur, especially the introduction of the concept of anatomical hepatectomy, bleeding, the main obstacle affecting the application of laparoscopic hepatectomy, has been overcome to some extent, and the initial irregular resection of the peripheral type has been expanded to regular lobectomy and hemihepatectomy involving the treatment of the hepatic hilum, and even extended hemihepatectomy and caudal lobectomy. At present, the indications for laparoscopic liver resection mainly include three categories: (i) benign liver tumors, the most common being hepatic hemangioma; (ii) malignant liver tumors, mainly including hepatocellular hepatocellular carcinoma (HCC); and (iii) intrahepatic bile duct stones.
With the gradual resolution of bleeding control problems in laparoscopic hepatectomy and the accumulation of clinical cases, other issues related to hepatectomy have also received increasing attention, the most important of which is the management of biliary tract problems, especially the proper management of biliary tract in patients with intrahepatic bile duct stones in hepatectomy.
I. Biliary tract problems involved in hepatectomy
Inappropriate biliary tract management during hepatectomy may lead to serious postoperative complications, such as biliary leakage, biliary obstruction, and even failure of liver function. The main reasons can be attributed to: (1) bile duct leakage or improper treatment of the separated section of the liver parenchyma; (2) bile duct leakage or biliary obstruction caused by improper treatment of the broken end of the hepatic duct or damage to the healthy bile duct in the bile duct treatment of the perihilar area; (3) residual bile duct stones inside and outside the liver.
1, Biliary tract problems involved in the treatment of separated sections of liver parenchyma. Liver resection is divided into anatomical hepatectomy and non-anatomical hepatectomy. The separated interface of liver parenchyma in anatomical hepatectomy is located between the functional lobes (segments) of the liver, and the separated interface does not contain the Glisson system, and thus theoretically does not involve the management of the biliary tract. However, in clinical practice, absolute adherence to the separation interface of the hepatic fissure is not possible. There is still a possibility of injury to the intrahepatic bile ducts during the separation of liver parenchyma in anatomic hepatectomy. Non-anatomical hepatectomy does not consider the Glisson system, and the treatment of the bile ducts is inevitably involved in the separation of the liver parenchyma, and improper treatment of the bile ducts in the hepatic section is one of the important causes of postoperative bile leakage in the section. Therefore, the liver section needs to be carefully examined after hepatectomy, and bile leaks excluded through the common bile duct or through the biliary cystic duct by injection of melanoma, etc. can be treated by suture ligation if necessary.
2, Treatment of bile ducts in the perihepatic hilar region. The bile ducts in the hilar region are the key to hepatic resection. The variation of intrahepatic bile ducts is concentrated in the porta hepatis, and its variation is in various ways, which often leads to serious consequences once mishandled. Therefore, bile ducts are usually not pre-treated outside the liver during hepatic resection, but rather dissociated during the separation of the liver parenchyma. Hepatic resections involving the management of the bile ducts in the hilar region are usually regular or subregular hepatectomies, especially hemihepatectomies. Damage to the contralateral bile duct during hemihepatectomy will result in serious consequences. The most important anatomical variant associated with hemihepatectomy is the D variant. In the D1 variant, the right posterior lobe bile duct can be mistaken for the caudal lobe bile duct and not be taken seriously. Given the complexity of intrahepatic bile duct variants, accidental injury to the variant bile ducts may be far more frequent than expected, and many injuries are overlooked because they do not cause obvious clinical consequences. For example, in left outer lobe resection, much of the segment IV bile duct originating from segment III bile duct can be lost, but this injury usually does not cause serious consequences.
It should be clear that the classical anatomical pattern of intrahepatic bile ducts is present in only about less than 60% of individuals. Therefore, during hepatectomy, the management of the bile ducts should be a safe strategy: (1) extrahepatic treatment of the bile ducts should be avoided in hepatectomy for non-biliary diseases; (2) the anatomical pattern of the intrahepatic bile ducts should be fully grasped preoperatively by high-quality imaging means as much as possible; (3) if there is any intraoperative doubt, the anatomy can be determined by frontal and lateral cholangiography; (4) no suspicious bile ducts should be spared, and bile ducts of larger caliber in the liver section should not be easily The bile ducts of large caliber in the liver section should not be easily sutured shut, but the liver segment or lobe to which they belong should be clearly identified, and the bile flow should be restored by bile-intestinal anastomosis if necessary.
3. Residual stones in the intra- and extrahepatic bile ducts. The basic indication for hepatic resection of intrahepatic bile duct stones is combined with atrophy of the liver parenchyma of the liver segment or lobe involved. Hepatic resection is also indicated when intrahepatic bile duct stones are difficult to remove or when there is a combined narrowing of the bile duct opening, especially when the lesion is located in the left half of the liver. An important complication of hepatic resection in patients with intrahepatic bile duct stones is the residual stones, including residual stones in the intrahepatic bile duct and residual stones in the common bile duct. The residual intrahepatic bile duct stones may be the result of failure to remove the original stones or the stones from the affected side may be dislodged to the healthy side. The former occurs in patients with diffuse intrahepatic bile duct stones (type III), while the latter occurs in patients with regional intrahepatic bile duct stones (type I or II). Since the latter hepatic resection is usually performed without resection of the extrahepatic bile duct and bile-intestinal anastomosis is performed, the stones in the liver are bound to be dislodged into the common bile duct after surgery and cause biliary obstruction. Therefore, in hepatic resection of patients with intrahepatic bile duct stones, the bile duct should be treated separately. After liver resection, the contralateral intrahepatic bile duct and common bile duct should be explored through the broken end of the bile duct or through the common bile duct, and combined with intraoperative imaging and cholangioscopic techniques to confirm that no stones remain in the intra- and extrahepatic bile ducts.
II. Features of biliary tract management in laparoscopic hepatectomy
The biliary tract management in laparoscopic hepatectomy is limited by the limitations of laparoscopic techniques, and the mature techniques and maneuvers of open surgery are difficult to perform under laparoscopy.
1, the separation of liver parenchyma will use a lot of hemostatic separation instruments such as ultrasonic knife and Ligasure, which can effectively control bleeding during the separation of liver parenchyma while also causing coagulative damage to the bile duct dissection, which may lead to postoperative bile leakage from the liver section.
2, During the treatment of the proximal hilar region, in order to simplify the surgical operation, cutting closures are often used to close and cut off the bile ducts and blood vessels together, without separate exploration and treatment of the bile ducts, which may lead to some biliary variants being overlooked during the operation.
3, In hepatectomy for patients with intrahepatic bile duct stones, it is relatively difficult to explore the bile ducts inside and outside the liver, which may lead to bile duct mishaps and stone residues.
III. Biliary tract management strategies in laparoscopic hepatectomy
To reduce the incidence of biliary complications after laparoscopic hepatectomy, the following points need to be noted in order to synthesize the biliary problems involved in hepatectomy and the characteristics of lumpectomy.
1, a refined dissection strategy should be adopted as much as possible during liver parenchymal separation, combining the methods of blood flow blockage into the liver and control of central venous pressure to control bleeding in the section during liver parenchymal separation, fully exposing the separation surface, and the thicker ducts encountered should be clamped closed before being separated by ultrasonic knife to avoid large pieces of coagulated separation. Thicker ductal tissues are also secure using cutting closures, with the disadvantage of higher costs.
2, Hepatic resection involving treatment of the perihilar region should be planned preoperatively by MRCP or other direct imaging methods to fully understand the biliary tract anatomy and variants. For hemihepatectomy, intraoperative imaging can be used to confirm the biliary anatomy to avoid accidental injury to the healthy bile duct.
3, fully understand the complexity of biliary tract management in hepatic resection of intrahepatic bile duct stones. Intrahepatic bile duct stones often have obvious atrophy of the liver parenchyma, coupled with the dilatation and deformation of the intrahepatic bile ducts and the filling of the stones, the anatomy of the bile ducts often changes significantly.
IV. Biliary tract management for hepatic resection of intrahepatic bile duct stones
1, the clinicopathological characteristics of intrahepatic bile duct stones: (1) the liver segment or lobe involved in the lesion is obviously atrophied and deformed, and there are obvious boundaries with normal liver tissue; (2) the interface between the lesioned liver segment (lobe) and normal liver parenchyma usually has hepatic vein distribution, and the dilated and thickened bile ducts are often closely related to the hepatic vein; (3) the opening of the bile ducts in the lesioned liver segment (lobe) is often obviously narrowed and filled with stones, and the narrowed opening is closely related to the adjacent normal (3) The bile duct opening of the diseased liver segment (lobe) is often significantly narrowed and filled with stones, and the narrowed opening is close to the bile duct opening of the adjacent normal liver segment (lobe). If the lesion is in the right half of the liver, the atrophy of the diseased liver and hyperplasia of the remaining liver may lead to atrophy-proliferative complex and changes in liver rotation and structural anatomical relationships of the porta hepatis.
2, In laparoscopic hepatectomy, the operator is usually more concerned with intraoperative bleeding control, so electrosurgical instruments such as ultrasonic knife and electrocoagulation as well as lumpectomy closures are usually used extensively intraoperatively. The former can lead to coagulative necrosis of the dissected bile ducts, which can cause bile leakage after postoperative necrosis detachment; while the use of cutting closures may make the operator neglect the precise exploration of the bile ducts while simplifying the surgical operation.
3, Based on the above considerations, in the liver resection of patients with intrahepatic bile duct stones, it should be noted that: ① fine separation strategy should be used in the process of liver parenchymal separation, and it is recommended that ducts larger than 1.0 mm should be clamped closed before separation; ② when the dilated bile duct is closely related to the main hepatic vein, it can be separated close to the bile duct to avoid tearing the hepatic vein to cause bleeding; ③ near the hepatic portal, the bile duct and portal vein should be treated separately, and it can be first The bile ducts can be opened for exploration, and the portal vein (and hepatic artery) branches can be dealt with after removing the stones in the disconnected bile ducts; ④ The use of intraoperative imaging and cholangioscopy is valued, as the former can provide a macroscopic understanding of the anatomy of the intrahepatic bile ducts and the distribution of stones, while the latter can help the complete removal of bile duct stones inside and outside the liver.
In conclusion, in laparoscopic hepatectomy, biliary issues mainly involve the management of the hepatic separation surface and the bile ducts in the perihilar region. The biliary anatomy and its variants should be fully understood preoperatively and intraoperatively as much as possible; the use of electrosurgical instruments such as ultrasonic knives should be noted for their coagulative damage that may lead to postoperative bile leakage; in hepatic resection for intrahepatic bile duct stones, the bile ducts and portal veins should be treated separately in the hilar region, and the bile ducts should be fully explored and stones removed.