The rapid development of laparoscopic surgery has led to increasing reports of difficult LC worldwide. Consensus guidelines from the 2018 Boston Conference and the Tokyo Consensus recommended standardized safety procedures, emphasizing the exposure of Rouviere’s sulcus and efforts to create CVS. If the CVS cannot be achieved due to scar formation or severe fibrosis during the operation, or if the Calot’s triangle is shrinking and the boundary is unclear, a bail-out approach should be considered, including conversion, fenestrating or reconstituting STC,[9] or the fundus-first technique. However, the disadvantages of both the fenestrating and reconstituting techniques include postoperative bile leaks.[6] Even long-term postoperative observation may reveal recurrent biliary events.[10] Bile leaks needs to be treated with continuous drainage or ERCP, thus increasing the length of hospital stay, delaying healing, and increasing the economic burden. Therefore, based on the surgeon’s laparoscopic experience and clinical observation, the advantages of laparoscopic local field magnification and fine dissection should be maximized to try to dissect and completely free the infundibulum and ligate it, to improve the postoperative outcomes.
The initial method of the infundibulum side boundary is used to reduce the dissection of Carlot’s triangle and avoid the occurrence of BDI.[11] Our technique does not use a constant anatomical landmark as a reference point. After exploring the infundibulum, only the trajectory of the common bile duct needs to be identified on the anatomical plane, and the cystic duct and artery are clearly defined. The dissected wound can then be safely resected without other luminal structures. Maintaining the subserosal approach can effectively avoid the effects of anatomical variations such as hepatobiliary duct variation and abnormal cystic duct confluence, consistent with the international consensus principle of closely following the GB dissection to avoid BDI. Another important technical feature includes the preservation of the cystic plate, which is part of the plate/sheath system of the liver. Severe inflammation can cause tissue edema and vasodilation, making the boundary between the GB and liver unclear. The peeling process produces a large amount of smoke that reduces visibility during the operation. If the anatomical surface penetrates deep into the liver and damages the blood vessels, it will cause more bleeding, thus increasing the surgical trauma and operation time. We therefore chose the GB–liver junction with clear boundaries and easy hemostasis as the resection plane, and destroyed the remaining mucosa by heat, resulting in no cases of postoperative abdominal effusion.
BDI is the most serious complication of LC and presents a problem for hepatobiliary surgeons throughout their learning curve. The reported incidence of BDI was 0.23%, and although the incidence has declined in recent years, it remains higher following laparoscopic compared with open cholecystectomy.[12] BDI associated with LC ranges from minor injuries to complex hilar injuries, as classified by Strasberg et al., with the most severe type being type E injuries, including persistent stenosis, complete occlusion, resection, or bile duct division.[13] The occurrence of BDI not only increases the length of hospitalization and the economic burden, but also means that the patient is likely to face recurrent bile duct strictures, requiring secondary hepatectomy, biliary-enteric or hepato-enteric anastomosis, eventually leading to liver transplantation or death.[14, 15] BDI is also a common cause of medicolegal problems for surgeons.[16] Therefore, in the procedure of difficult LC, we make the following recommendations. 1) Severe inflammation and excessive compression of the swollen cysts will distort the local anatomical structure resulting in anatomical difficulties, and the complete removal of fat and fibrous tissues in Calot’s triangle cannot be achieved. In addition, dissection of the area should be minimized at this time to avoid BDI. 2) Detection of the infundibulum and identification of the sentinel lymph node allows the infundibulum to be dissected circumferentially after the lateral dorsal approach, while retaining the serosal layer of the dorsal part. 3) The limitation of the anatomical plane means that the trajectory of the common bile duct, junction of the infundibulum and the cystic duct, and the anterior and posterior branches of the artery entering the GB can be seen visually.
Preoperative examination is important to realize the above steps, including safe resection of the infundibulum, no BDI, and a low conversion rate. Detailed imaging examinations are critical for surgical planning, especially in cases of difficult GB assessments, such as patients with Mirizzi’s syndrome, aberrant hepatic ducts/cystic duct insertions, and rare cancers. Preoperative ultrasound can provide an initial impression, including diagnosis of gallstones, measurement of swelling, and GB wall thickness. However, we consider MRCP to be the most important and effective method for assessing the severity of cholecystitis inflammation and the extrahepatic bile ducts.[17] Magnetic resonance imaging (MRI) can show the degree of GB enlargement and the condition of common bile duct stones. Furthermore, the faster acquisition protocol allows for good tissue contrast and can also determine the condition of the GB wall, including thickness stratification, early edema, necrosis, or later fibrosis or scars. Importantly, MRCP can display the adjacency between the enlarged GB, the common hepatic duct, and the common bile duct, and can detect variations in the cystic duct and bile duct, providing the surgeon with a systematic understanding of the entire biliary system and GB before surgery, thus helping to avoid BDI. MRCP is important for the diagnosis, treatment planning, and prognosis of AC, and should be completed even before emergency surgery.[18] ERCP is used in cases where MRI examination is not possible and is necessary for the treatment of common bile duct stones. In addition, enhanced computed tomography can be used to rule out the possibility of tumors and to check the blood vessels in the hilar region.[19] Operative procedures in our institution rarely include intraoperative imaging techniques.
None of the patients in the current study had developed BDI by 5 years after difficult LC using the described technique. This method thus has several advantages 1) Surgical preservation of the cystic plate mucosa is simple and quick, saving operating time for subsequent procedures, and also reduces bleeding because the plate/sheath system of the liver is not penetrated. 2) Exploration of the infundibulum cavity not only avoids the occurrence of residual stones, but also helps to confirm the overall shape from the inside out, to lay the foundation for the next step of dissection. 3) The method can effectively avoid damage to blood vessels and hepatic bile ducts, and thus avoid BDI.