There are various treatment options for gallbladder stones combined with common bile duct stones, including traditional open cholecystectomy and common bile duct extraction, endoscopic sphincter of Oddiotomy for subsequent laparoscopic cholecystectomy (EST+LC), and laparoscopic one-stage cholecystectomy + common bile duct exploration for stone extraction (LCBDE+LC). However, the most ideal treatment for gallbladder stones combined with common bile duct stones is still controversial [1-3]. LCBDE combined with LC can treat both gallbladder stones and common bile duct stones in one operation, with the advantages of short hospital stay, low treatment cost, preservation of Oddi sphincter function and low long-term complication rate, and stone removal rate, early complication rate and mortality rate are better than EST combined with LC [ 1,4-9]. With the improvement of laparoscopic techniques and equipment, the use of LCBDE has gradually increased and is considered more effective and preferable than EST combined with LC for appropriate patients and is indicated for the vast majority of gallbladder stones combined with common bile duct stones [1,5]. In some biliary disease treatment centers, LCBDE combined with LC has become the standard approach for the treatment of gallbladder stones combined with common bile duct stones. In this paper, we describe the technique and access selection for laparoscopic common bile duct exploration. There are three main approaches for laparoscopic common bile duct exploration, namely, the transcystic approach, the transcoledochal approach, and the transcoledochal approach and the transcoledochal incision at the intersection of the cystic duct and common bile duct. Transcystic approach: it means incision of the cystic duct and insertion of a contrast catheter through the cystic duct to understand the bile duct during cholangiography, or insertion of a choledochoscope for biliary exploration and stone extraction. The indications are [10]: 1. The condition of the cystic duct is suitable so that the mesh basket, catheter or choledochoscope can enter the bile duct smoothly, for example, the cystic duct is open, the diameter is greater than 3 mm, and there is no obvious distortion or variation; 2. The diameter of the stone in the bile duct should not exceed 8 mm in general, and if the stone is too large, it is difficult to remove it through the cystic duct; 3. The stone should be located below the confluence of the cystic duct and the common bile duct, and in most In most cases, before the cystic duct converges into the common bile duct, it will be parallel to the common bile duct down a section, so that it is difficult to reach the common hepatic duct and intrahepatic bile duct after the biliary tractoscope enters the common bile duct through the cystic duct, so the stones located in the common hepatic duct and intrahepatic bile duct are difficult to be removed through the cystic duct. During the operation, the cystic duct should be fully freed and tracted, and the cystic duct should be gradually dissected and freed until it converges into the common bile duct, and the relationship between the “three ducts” should be clearly seen, and the cystic duct should be clamped by the neck of the gallbladder first, and if the cystic duct is thicker, it should be ligated with a silk thread, and the anterior wall should be cut along the cystic duct longitudinally. If bile flow or spiral flap structure is seen during incision, it indicates that the whole anterior wall of the cystic duct has been incised, continue to incise about 0.5 cm, stop bleeding with electric hooks, gently expand with curved forceps after incision, prop open the spiral flap, insert into the common bile duct along the course of the cystic duct, and gently expand the confluence. If intraoperative imaging is available, a thin trocar can be inserted through the incision in the midclavicular line and a mesh basket for stone extraction can be inserted, and the mesh basket is inserted through the cystic duct to the lower part of the common bile duct, first passing through the cholangiogram, and if stones are seen they are removed directly with the mesh basket (Figure 1, 2, 3). If the preoperative stone diagnosis is clear, the mesh basket can also be tried to remove the stone directly first, and then the cholangiogram will be performed to see if the stone is removed, which can save the operation time. When inserting the cystic duct with the mesh basket, care should be taken to avoid puncturing the cystic duct and causing false passage, resulting in stone extraction failure. If intraoperative imaging is not available or if direct retrieval with the mesh basket is unsuccessful, a choledochoscope is inserted through the cystic duct and the stone is retrieved with the mesh basket under direct visualization of the choledochoscope (Figures 4, 5, 6). Most stones in the common bile duct fall from the gallbladder into the common bile duct. In these patients, the cystic duct is relatively thick and can usually be passed through the cystic duct using a choledochoscope with a diameter of less than 5 mm. If the cystic duct is thin, the cystic duct can be dilated first by passing a thin guidewire through the cystic duct, then placing a columnar balloon under the guidance of the guidewire, and the balloon is filled with water and pressure to dilate the cystic duct so that the choledochoscope can enter the cystic duct. If the stones are completely removed by choledochoscopy and the end of the bile duct is patent, the cystic duct can be directly clamped and finally the cholecystectomy is routinely completed. If the cystic duct incision is very close to the common bile duct, it is not easy to clip it completely using titanium clips, and there is a risk of bile leakage after surgery, it is more prudent to use 3 0 or 4 0 absorbable sutures for the stump of the cystic duct. If there are more stones and they are easy to clip, or if the network repeatedly operates through the papillae causing papillary spasm and edema, a thin drainage tube can be placed through the cystic duct to the common bile duct to reduce the bile duct pressure and prevent bile leakage, and also to facilitate postoperative cholangiography. The postoperative recovery process of the transcystic duct route for choledochal exploration and stone extraction is similar to that of LC alone, and the operation is relatively simple without suturing the common bile duct [11], without the fear of damaging the common bile duct and postoperative bile duct stricture, and with a low complication rate; therefore, laparoscopic transcystic duct exploration and stone extraction is the preferred method for the treatment of common bile duct stones [3-4,11]. Transcystic route: when the number of bile duct stones is large and bulky or the stones are located above the common hepatic duct, it is difficult to remove the stones by the transcystic route, and if the cystic duct and common bile duct confluence is mutated or the cystic duct is twisted and severely incompetent, it is also impossible to perform transcystic duct exploration for stone extraction, and then the common bile duct needs to be incised for stone extraction [3,12]. After opening the Calot triangle, the anterior wall of the common bile duct is carefully freed to reveal the anterior wall of the common bile duct, and a longitudinal incision is made along the common bile duct. The size of the incision depends on the stone and is usually around 1 cm, which can be done by electric incision, and the incision can be extended if the stone is large. After incision, the bile is aspirated and if stones are seen, they are removed by direct clamping. There are three general methods of removing stones from the common bile duct, one is water flushing method, convenient, non-invasive, suitable for small stones or stone residues, can be inserted directly into the common bile duct with flushers, pressure flushing, generally small stones can be flushed out, saving surgical time; biliary instrument extraction method, generally suitable for stones visible in the field of view, if the stones are not in the field of view, the operator needs to have a feel when removing the stones, such as improper operation is easy to If the stone is not within the field of view, the operator needs to feel it during stone extraction, and if the operation is not done properly, the mucous membrane of the bile duct will be clamped, causing possible damage to the bile duct. The choledochoscope is usually inserted through the main operating hole (subxiphoid trocar) or sometimes through the operating hole under the midclavicular line. The lower end of the trocar is aligned with the bile duct incision with the help of the trocar so that the choledochoscope can be inserted accurately into the bile duct. If the stone is embedded and difficult to be caught in the mesh basket, then lithotripsy is needed first. After the stones are removed, the biliary tractoscope is then carefully examined for abnormalities in the intrahepatic and extrahepatic bile ducts, and a suitable T-tube is selected according to the thickness of the bile duct. If necessary, the long arm of the T-tube can be lifted outside the abdominal cavity and a T-tube imaging can be performed to further clarify whether the stones are removed (Figure 7, 8, 9). Sometimes a small amount of leakage from the stitches is not a concern, as long as the T-tube is opened to keep the bile flowing freely and a good drainage tube is placed in the abdomen, there is usually no bile leakage after surgery. Laparoscopic choledochotomy and T-tube drainage requires higher lumpectomy technique of the operator, and if the diameter of the bile duct is thin, there is a risk of postoperative bile duct stricture, and the time to place the T-tube is longer than that of open surgery, and it takes 4 to 6 weeks to remove the T-tube, which brings certain impact on the quality of life of the patient, and there may be complications of T-tube drainage of the common bile duct, including sinus tract tearing during extraction, T-tube slippage, T-tube distortion, and abnormal bile drainage [13]. These disadvantages make laparoscopic common bile duct T-tube drainage reduce the minimally invasive advantages of laparoscopy, so laparoscopic one-stage suturing of the common bile duct has been tried [14-16], and if there is no preoperative manifestation of biliary stricture obstruction, liver function is basically normal, no residual stones are seen on intraoperative cholangioscopy or cholangiography, and there is basically no mechanical irritation to the terminal opening of the common bile duct, one-stage suturing of the common bile duct without placing a T-tube can be considered . One-stage suturing is safer if the patient has a preoperative ENBD or PTCD drainage tube. One-stage suturing of the common bile duct is still controversial and needs to be chosen carefully. Some randomized controlled studies have concluded that laparoscopic common bile duct one-stage suturing is superior to common bile duct T-tube drainage [14-16], indicating that with the advancement of laparoscopic techniques and experience, laparoscopic common bile duct one-stage suturing is completely feasible as long as the indications are strictly mastered [7,17]. Transcystic duct and common bile duct confluence route: if the cystic duct is thin and difficult for the choledochoscope to enter or the stone is difficult to be removed through the cystic duct, and the diameter of the common bile duct is normal such as direct incision of the common bile duct worrying about the risk of postoperative biliary stricture, in this case the transcystic duct and common bile duct confluence route can be considered, that is, incision along the cystic duct until it confluences into the common bile duct and incision of the common bile duct a little, so that the choledochoscope can directly enter After lithotripsy, the decision to suture the bile duct directly or to place a T-tube for drainage is based on the final bile duct exploration. As the confluence of the cystic duct and common bile duct is opened, the choledochoscope enters directly into the common bile duct and can reach the common hepatic duct and intrahepatic bile duct. The bile duct at the confluence of the cystic duct and common bile duct is relatively dilated and the bile duct is not completely opened, which greatly reduces the risk of bile duct stricture. Transcystic duct and common bile duct confluence incisional exploration not only overcomes the disadvantage of difficult access to the common bile duct due to conditions such as small or twisted cystic duct, but also avoids the risk of bile duct stenosis after direct incisional exploration of the common bile duct, and one-stage suture of the bile duct also reduces the incidence of bile leakage, which is worthy of further development.