Minimally invasive surgery has revolutionized the way we perform surgery due to the benefits of enhanced recovery, specifically less postoperative pain and fewer wound-related complications. These surgical techniques have become widespread and the gold standard for the management of certain entities as a result of outcomes data, improved equipment (including smaller, user-friendly articulating instruments and robotic-assisted surgery), patient expectations, and the easily accessible worldwide media.

The advanced minimally invasive surgical techniques in this chapter address the role of intraoperative imaging and the management of bile tract stones, tumors, and cysts. These approaches are ideally offered in an environment where a multidisciplinary approach is provided. As the demand for less invasive and more subspecialized expertise increases, knowledge of how this field is evolving will be important in offering our patients the best clinical care with the least associated procedural risk.

Clarifying biliary anatomy to facilitate safe surgical dissection or identifying biliary ductal injuries is essential. A meticulous dissection of the gallbladder with the “critical view of safety” approach has been used for this purpose.¹ When this technique or other surgical approaches do not provide this information or when they cannot be performed safely, the use of intraoperative imaging such as intraoperative cholangiogram (IOC) is required. Additional indications for the use of IOC include the presence of jaundice, elevated liver function or pancreatic enzymes levels, biliary ductal dilation, or stones on imaging. A meta-analysis revealed that the incidence of unsuspected retained stones after a cholecystectomy was 4%, with only 15% of these going on to cause clinical problems.² The probability of this pathology can be classified as low (<5%), medium (5%-50%), and high (>50%) according to bilirubin level (<1.8, 1.8-4, and >4 mg/dL), dilation of common bile duct (CBD; >6 mm), and clinical signs of cholangitis.³ Because small stones may pass spontaneously, a preoperative endoscopic retrograde cholangiography (ERC) is not necessary or efficient in most cases, and laparoscopic cholecystectomy with IOC will suffice to document a clear CBD during cholecystectomy; if needed, a postoperative ERC can be used for those with clinically significant residual stones.^4-6 Using fluoroscopic IOC, stones can be identified with greater than 95% sensitivity and specificity, with a 5% false-positive rate and 1% false-negative rate, although these rates are highly variable depending on the study.⁷ Magnetic resonance cholangiography (MRC) has a high sensitivity (90%) and specificity (95%) for choledocholithiasis with a low-risk profile compared to ERC and thus occupies a place in the management algorithm when there is medium probability.⁸ If stones are encountered during MRC, then proceeding with preoperative ERC is recommended. If stones are not diagnosed on MRC, proceeding with a laparoscopic cholecystectomy with IOC is recommended. A proposed algorithm to address clinically suspected CBD stone is presented (Fig. 66-1).

While the information obtained from IOC is valuable, its routine versus selective use continues to be debated due to the associated increased cost from additional instrumentation and increased operating room (OR) time on the one hand and decreased readmission rates from postcholecystectomy syndrome on the other.^9,10

Other forms of intraoperative imaging including ultrasonography and infrared-activated fluorescence, although used less often, are finding their way into the OR as a result of their unique advantages. Ultrasonography is highly sensitive (83%-100%) and specific (98%-100%) in identifying CBD stones and ductal dilatation and is more cost ­effective compared to IOC (ultrasonography machines cost ­$40,000-$75,000, whereas C-arms and associated supplies cost $500,000). Factors that have limited its widespread adoption include the lack of ­therapeutic capabilities and operator dependency.¹¹ An approach such as indocyanine green (ICG) fluorescence would be advantageous in avoiding radiation exposure and penetrating the biliary ductal system as needed for direct injection of a contrast dye during standard IOC. Its reported ease of use and relatively low cost are another benefit. ICG is hydrophilic and binds to albumin in plasma as well as to α₁-lipoprotein. It is exclusively eliminated in the liver and has no metabolism. ICG is injected intravenously approximately 60 minutes prior to making a surgical incision, and when illuminated by infrared light, the dye manifests fluorescence. Limiting factors of this approach include allergies to ICG dye, inability of the infrared light to penetrate thick and or deep tissue such as what would be encountered in morbid obesity or severe inflammation, and the need for specialized imaging system equipment.^12-14

For a successful IOC, the patient should be positioned on the appropriate OR table in a way that the C-arm can have adequate access to the patient’s right upper abdomen during the laparoscopic cholecystectomy. The most common approach for an IOC is using contrast dye injected directly into the infundibulum of the gallbladder or cystic duct. Advantages of accessing the gallbladder infundibulum directly include avoiding a ductotomy on what may turn out to be the CBD instead of the cystic duct. Another advantage is its ease of cannulation compared to the relatively smaller cystic duct. Disadvantages include the possibility that the dye may not leave the gallbladder due to an occluded ­infundibular-cystic duct junction from an impacted stone or inflammation, ­tortuosity of the cystic duct, and presence of the spiral valves of Heister. In either approach, proximal occlusion with either a grasper or clip will avoid inadvertent backflow of the dye and help orient the imaging. Traction on the gallbladder will provide additional exposure and duct alignment for better imaging interpretation. The cholangiogram catheter system should be flushed thoroughly with saline prior to its use to avoid misinterpretation of the air bubbles injected into the biliary ductal system from the tubing. The imaging should include the cystic duct, left and right hepatic ducts, common hepatic duct, and CBD, and the contrast should be seen filling the duodenum. To assist with improved visualization of the proximal biliary ductal system, enhanced filling by the contrast occurs with placing the patient in Trendelenburg position and administering 1 to 2 mg of intravenous morphine to induce sphincter of Oddi contraction. Visualization of the duodenum filling with contrast can be enhanced by administering 1 mg of intravenous glucagon to allow for sphincter of Oddi relaxation. Even with ideal imaging, it is important to always use caution because misinterpretation is possible in cases where biliary ductal injuries occur.¹⁵

Intraoperative common duct exploration has not gained wide acceptance in the surgical community, as shown in a US survey-based study and a Swedish nationwide retrospective study.^16,17 Although preoperative ERC is the predominant method of bile duct clearance in the setting of laparoscopic cholecystectomy, laparoscopic CBD exploration (LCBDE) has been shown to be a safe and effective single-stage option for the management of CBD stones due to the feasibility of successful completion laparoscopically (96%), few major complications (5%), and excellent long-term results.^18,19 When compared to preoperative ERC and subsequent laparoscopic cholecystectomy, both approaches were equivalently effective in detecting and removing CBD stones and were equivalent in overall cost and patient acceptance.^20,21 LCBDE does require advanced surgical expertise, longer OR time, and specialized equipment; however, LCBDE has been shown to reduce the length of hospital stay, reduce recurrent CBD stones, and eliminate the potential risks of ERC-­associated pancreatitis and papillary stenosis with a single procedure.^22-26 When possible, a transcystic route is preferred to the transcholedocotomy approach due to the lower incidence of bile leaks and decreased overall morbidity.²⁷ A transcystic approach may not be feasible with anomalous anatomy, proximal stones, strictures, and large (>6 mm) or numerous (>5) stones.²⁸ Although large (>7 mm) and impacted stones have been associated with failure of stone clearance by LCBDE and may necessitate conversion to an open CBD exploration or reliance on postoperative endoscopic retrograde cholangiopancreatography (ERCP), others have performed successful LCBDE stone extraction after failed preoperative ERC. Other factors such as adhesions and altered anatomy seem to determine LCBDE success or conversion to an open ­procedure.^29,30 Intraoperative common duct exploration has been shown to be less effective than postoperative ERCP in terms of ductal clearance in cases of emergency surgery.³¹

After accessing the cystic duct, a flexible-tip guidewire is advanced into the CBD. To allow access of the choledocoscope, a balloon catheter is used to dilate the cystic duct to 3 to 5 mm. Stone extraction proceeds in either a retrograde fashion through the cystic duct with a wire basket or in antegrade fashion by dilating the ampulla and pushing the stone through with a balloon catheter. Remaining debris should be flushed, and a completion cholangiogram should confirm clearance and identify any procedural-related ductal injuries. Traditionally a T-tube was left in place for drainage after CBD exploration, but recent studies have shown that primary duct closure following LCBDE is safe, can be employed routinely as an alternative to T-tube insertion, and has a short hospital stay and low morbidity rate.^32,33