Management of Common Bile Duct Stones

Detection of Common Duct Stones

The most common clinical presentations for patients with choledocholithiasis are cholecystitis, pancreatitis, biliary colic, cholangitis, and jaundice. Cholangitis is most predictive, with some studies showing 100% specificity. However, none of the other more common clinical presentations are predictive. Tranter and Thompson demonstrated a 14% incidence of choledocholithiasis in 1000 consecutive laparoscopic cholecystectomies (LCs) during which routine intraoperative cholangiogram was performed. Patients presenting with cholecystitis, biliary colic, pancreatitis, and jaundice were found to have common duct stones 7%, 16%, 20%, and 45% of the time, respectively.

Transabdominal ultrasonography is the most common imaging modality used in the initial evaluation of patients who present with biliary symptoms. However, compared with its high accuracy in diagnosing cholelithiasis and cholecystitis, transabdominal ultrasound has only 50% to 80% sensitivity in detecting common duct stones, depending mostly on the presence of CBD dilation. Some studies have shown that if sonographic CBD dilation is combined with age older than 55 years and abnormal liver enzymes, choledocholithiasis can be predicted up to 95% of the time.

For those patients in whom choledocholithiasis is suspected, more definite preoperative tests may be performed. ERC is highly specific in diagnosing common duct stones and may be therapeutic with sphincterotomy and duct clearance. However, this procedure is invasive and associated with significant morbidity, including post-ERC pancreatitis, bleeding, sepsis, and perforation. A prospective study of 1177 consecutive ERCs demonstrated a 30-day morbidity rate of 15.9%, with a procedure-related mortality of 1%. The morbidity of the ERC procedure is thought to be caused by two primary mechanisms: mechanical injury from repeated instrumentation of the sphincter of Oddi and the biliary and pancreatic ducts, in addition to hydrostatic injury incurred during injection of the contrast under pressure. In addition, up to 60% of patients undergoing ERC prior to LC will be found not to have common duct stones and will therefore have undergone an unnecessary and invasive test.

Endoscopic ultrasound (EUS) and magnetic resonance technology have been used to diagnose choledocholithiasis. To decrease unnecessary ERC/ES, some centers now routinely perform EUS before ERC. The sensitivity and specificity of EUS have been reported as high as 98% and 99%, respectively. In light of these findings and the decreased risk of pancreatitis when compared with ERC, two clinical guidelines advocate EUS in symptomatic patients with indeterminate risk of choledocholithiasis. In addition, magnetic resonance imaging has shown promise as an alternative means to diagnose choledocholithiasis, with a study showing a positive predictive value of 95%. In patients with indeterminate risk for choledocholithiasis, magnetic resonance cholangiopancreatography (MRCP) is a valuable, noninvasive option that does not incur the same morbidity risks as ERC and, to less degree, EUS. MRCP is also useful in patients who have had a prior Billroth II or Roux-en-Y gastrojejunostomy, particularly in patients having undergone a gastric bypass operation for the treatment of morbid obesity. However, MRCP is quite expensive and does not have the therapeutic possibilities of ERC.

Preoperative Endoscopic Therapy

ERC plays an important role in the treatment of common duct stones for older adults or debilitated patients and in patients who present with jaundice, cholangitis, or severe pancreatitis. For patients who may not tolerate an operation, performing ERC/ES and leaving the gallbladder in situ is a good alternative to cholecystectomy, because up to 85% of patients remain symptom free with up to 70-month follow-up. Other studies have demonstrated a decreased mortality for patients undergoing ERC versus surgical drainage for cholangitis and severe pancreatitis. If a patient with choledocholithiasis does undergo successful preoperative ERC, early LC should be considered because a randomized trial showed 36% recurrent biliary events within 6 to 8 weeks. In addition, two prospective randomized trials and a systematic review comparing two-stage versus single-stage management demonstrate equivalent success rates for LCBDE versus preoperative ERC/ES followed by LC. One-stage LCBDE has also been shown to significantly reduce hospital stays and hospital costs. Tai et al. showed that LCBDE had a 100% success rate in salvaging failed preoperative ERC/ES.

Much of the morbidity associated with ERC/ES is associated with the sphincterotomy. Endoscopic papillary dilation has been suggested as an alternative; a multicenter randomized study demonstrated that endoscopic balloon dilation resulted in a higher rate of pancreatitis when compared with sphincterotomy and recommended that it should be avoided in routine practice. However, in patients with coagulopathy, dilation should be the preferred method for endoscopic removal of common duct stones.

Intraoperative Diagnosis of Common Bile Duct Stones

For patients undergoing LC, the CBD should be imaged intraoperatively if choledocholithiasis is suspected (past or present elevation of liver function tests, gallstone pancreatitis, CBD dilation, or choledocholithiasis on preoperative ultrasound) or if the biliary anatomy is unclear. This can be achieved by intraoperative cholangiography (IOC) or laparoscopic ultrasonography (LUS). Before either procedure, a clip is applied high on the cystic duct at its junction with the gallbladder to prevent stones migrating down the duct. To perform IOC, the cystic duct is partially transected and “milked,” moving stones away from the CBD and out the ductotomy. A cholangiography catheter is inserted into the cystic duct and secured in place with a clip, grasping jaws, or balloon fixation. Cholangiography is preferentially performed with real-time fluoroscopy while injecting 5 to 10 mL of water-soluble contrast medium diluted 1 : 1 with normal saline. The following characteristics should be ascertained: (1) the length of cystic duct and location of its junction with the CBD, (2) the size of the CBD, (3) the presence of intraluminal filling defects, (4) the free flow of contrast into the duodenum, and (5) the anatomy of the extrahepatic and intrahepatic biliary tree.

Evaluating the CBD by LUS is an alternative to IOC, even though most surgeons do not have experience with this technique. A prospective study showed that LUS had greater sensitivity and equal specificity compared with IOC for detecting CBD stones. LUS has better resolution than transabdominal ultrasonography, and, in experienced hands, LUS appears to be as accurate as cholangiography for demonstrating choledocholithiasis and can be performed more rapidly. In a prospective, multicenter trial with 209 LC patients, the time to perform LUS (7 ± 3 minutes) was significantly less than that of IOC (13 ± 6 minutes). The study also showed that LUS was more sensitive for detecting stones but that IOC was better in delineating intrahepatic anatomy and defining anatomic anomalies of the ductal system. The authors concluded that the two methods of duct imaging were complementary. These conclusions were confirmed by two meta-analyses demonstrating that the diagnostic accuracy of LUS is comparable with IOC in detecting choledocolithiasis while avoiding ionizing radiation and decreasing imaging time when compared with IOC.

Laparoscopic Common Bile Duct Exploration

When CBD stones are found, laparoscopic CBD exploration can take place through the cystic duct (transcystic technique) or by directly incising and opening the CBD with stone retrieval (laparoscopic choledochotomy). In the transcystic duct approach, small stones (<2 to 3 mm) can often be flushed through the ampulla into the duodenum. Intravenous glucagon (1 to 2 mg) may be used to relax the sphincter of Oddi, followed by vigorous flushing of 100 to 200 mL of saline. When these methods fail, a helical stone basket can be passed over a guidewire through the cystic duct and into the CBD to extract stones under fluoroscopic guidance. If attempts at transcystic basket extraction fail, a choledochoscope (≤10 French) should be tried next to remove the stones under direct vision. If the CBD stone is larger than the lumen of the cystic duct, the cystic duct should first be balloon dilated to a maximum of 8 mm diameter but never larger than the internal diameter of the CBD. The choledochoscope is then passed into the peritoneal cavity through the midaxillary port, using a sheath to prevent damage to the scope by the port's valve. The choledochoscope is then inserted through the cystic ductotomy into the CBD under direct vision ( Fig. 109.2 ). Continuously infusing saline through the biopsy channel helps to dilate the lumen of the duct facilitating visualization. The tip of a Segura-type stone basket is advanced through the working channel of the scope beyond the stone and opened. As the basket is pulled backward and rotated, the stone is ensnared ( Fig. 109.3 ). A completion cholangiogram or ultrasound should always be performed to conclusively demonstrate clearance of the duct. Because of tissue edema secondary to ductal dilation and manipulation, the cystic duct stump is ligated (rather than clipped) for added security.

Successful transcystic duct clearance has been reported in 80% to 98% of patients in recent series. Complications, such as infection and pancreatitis, have been reported in 5% to 10% of patients, with a mortality rate of 0% to 2%. The duration of hospitalization following an uncomplicated transcystic duct stone extraction is the same as that for LC alone, averaging 1 to 2 days. The main advantage of the transcystic approach is that it avoids choledochotomy. Poor candidates for transcystic extraction techniques are those with large or multiple CBD stones, those with stones in the proximal ductal system, and those with small or tortuous cystic ducts.

Other novel transcystic approaches include balloon dilation of the sphincter of Oddi and antegrade sphincterotomy. Carroll et al. reported successful clearance of CBD stones in 17 (85%) of 20 patients by balloon dilation; however, even in this small series, three patients (15%) experienced mild postoperative pancreatitis. This method should be avoided in patients with preexisting pancreatitis, biliary dyskinesia, or anatomic sphincter anomalies. A sphincterotome may be inserted through the cystic duct and its tip placed just through the ampulla of Vater into the duodenum. A duodenoscope is passed transorally and used to allow proper positioning of the sphincterotome before applying current to perform a sphincterotomy. DePaula et al. have reported the performance of transcystic antegrade sphincterotomy at the time of LC in 22 patients, and all had successful stone clearance without complications; the procedure added only 17 minutes to the operation.

If the transcystic approach fails, there are two primary options for management. For surgeons comfortable with intracorporeal suturing techniques, a laparoscopic choledochotomy can be performed. Alternatively, the surgeon can choose to complete the cholecystectomy and refer the patient for postoperative ERC to obtain clearance of the CBD stones. The indications for performance of a laparoscopic choledochotomy are multiple or large stones or those positioned within the proximal bile ducts in patients with a CBD diameter larger than 8 to 10 mm. Stay sutures are usually placed on either side of the midline of the anterior CBD wall to allow anterior traction on the duct. A longitudinal choledochotomy is made on the distal CBD, of adequate length to allow easy placement of a choledochoscope and removal of the largest stone.

After the stones are removed under endoscopic visualization, the ductotomy is closed either primarily or over an appropriately sized T tube. Some centers have used transcystic tubes (C tubes) or antegrade stenting with choledochorrhaphy for CBD drainage. Common duct closure is accomplished with fine absorbable sutures using intracorporeal suturing techniques, and if a T tube or C tube is used, it is exteriorized through the lateral port site. Following transcholedochal stone extraction, an active drain is placed in the subhepatic space. Studies have demonstrated comparable results regardless of the technique of duct closure. Others have shown decreased complications with primary closure compared with T tube use, as well as decreased operative time and hospital stay. The patient is generally discharged 2 to 4 days postoperatively. If a T tube is used, a final cholangiogram is performed 14 to 21 days postoperatively with removal of the tube if no abnormalities are noted. Retained stones demonstrated by T tube cholangiography may be effectively removed percutaneously after allowing maturation of the T tube tract. Percutaneous extraction is successful in more than 95% of patients with retained stones ; otherwise postoperative ERC will be required.

Overall, laparoscopic choledochotomy is successful in 84% to 94% of patients, with a minor morbidity rate of 4% to 16% and a mortality rate of 0% to 2%. Potential complications of this technique include CBD laceration, bile leak, sewn-in T tubes, and stricture formation. Many surgeons have not mastered laparoscopic suturing and feel uncomfortable closing the choledochotomy for fear of a resultant stricture; however, no biliary strictures have been identified in three recently published studies that looked at the long-term outcomes of more than 640 patients undergoing LCBDE with a mean follow-up of more than 3 years. Similarly, there was no increased risk of recurrent CBD stones for patients who underwent primary choledochorrhaphy compared with T tube closure.

Some centers have used intraoperative ERC as an alternative to CBD exploration. Enochsson et al. reported that the technique was safe, with 93.5% duct clearance; however, it added 1 hour of operative time compared with LC alone. In another study, intraoperative ERC was as effective as LCBDE in duct clearance (approximately 90%), but morbidity was doubled, and hospital costs were significantly increased. Intraoperative ERC also relies on preoperative coordination with a skilled endoscopist if the surgeon is not trained in ERC. Positioning in the operating room also makes the technique more difficult than in the endoscopy suite.

The possibility of finding CBD stones at the time of LC and potential treatment plans must be discussed with the patient before the operation. Many surgeons routinely leave CBD stones in place during LC for planned postoperative endoscopic removal. This strategy may be appropriate in centers with expert interventional endoscopists with demonstrated high cannulation rates. If this expertise is not available, intraoperative management of the CBD is warranted. A prospective study reported that more than 50% of clinically silent CBD stones passed spontaneously within 6 weeks. Neither the number of stones nor stone size was predictive of spontaneous stone passage. The authors suggested a short-term expectant management approach for patients with clinically silent choledocholithiasis.