Direct cholangiography: Approaches, techniques, and current role

History

Fluoroscopic imaging of the biliary tree was first reported by Burckhardt and Müller in 1921, who performed cholecystocholangiography via percutaneous puncture of the gallbladder. The first report of PTC was by Huard and Do-Xuan-Hop in 1937, who performed cholangiography with Lipiodol, a suboptimal contrast agent. Transhepatic cholangiography as a diagnostic tool gained popularity 15 years later, after Carter and Saypol’s (1952) discussion of PTC with the use of a water-soluble contrast agent. In the ensuing years, many investigators described a variety of different techniques, including the use of sheathed or unsheathed needles of various sizes and different puncture sites. These procedures were associated with a significant risk of bile peritonitis, especially in obstructed biliary systems, and less frequently, bleeding. Fine-needle transhepatic access to the biliary tree was first developed at Chiba University and was presented by Ohto and Tsuchiya (1969), and later by Tsuchiya (1969). Numerous additional reports have also described decreased complications with fine-needle transhepatic access, and this technique has generally been accepted as the standard (see Chapter 31 ).

Evaluation of the biliary tree by noninvasive imaging techniques have largely replaced transhepatic cholangiography (see Chapters 13 and 16 ). In 1985 Kadir reported that less than 5% of patients referred for evaluation of biliary disease required concomitant drainage procedures. With continued advancement of cross-sectional imaging techniques, in particular MRCP (see Chapters 13 , 16 and 19 ), percutaneous fluoroscopic imaging of the biliary tree with contrast injection is typically performed only as part of a planned interventional procedure.

Imaging evaluation of the biliary tree with MRCP or CECT is noninvasive, does not require sedation, and is generally regarded as safe (see Chapters 13 and 16 ). With direct needle puncture and contrast injection in the biliary tree, only bile ducts in continuity with the punctured duct are visualized. In the presence of bile duct isolation, multiple percutaneous needle punctures may be required to visualize the entire biliary tree (see Fig. 20.2 ). Even with multiple transhepatic bile duct needle punctures, CT imaging performed at the time of the procedure can be helpful to ensure that the biliary tree has been fully imaged. Alternatively, MRI and CECT can image the entire biliary system and can demonstrate the presence and severity of bile duct isolation (see Fig. 20.1 ). MRI or CECT can visualize the bile duct wall, liver, and surrounding structures, often providing more clinical information that could be relevant to patient care.

Preprocedural preparation

Patients should undergo cross-sectional imaging (CECT or MRI) before fluoroscopic imaging of the biliary tree. This is particularly so in patients who have undergone prior liver surgery or liver resection. MRI or CECT are the imaging modalities of choice because these studies depict the level of bile duct obstruction, patency of the portal venous system, the relationship of the liver and bile ducts to other structures, and the presence of tumors or lobar atrophy. Knowledge of this information could improve the chance of successful and safe bile duct puncture (see Chapter 31 ).

Coagulation parameters and platelet count should be checked before the procedure and corrected if necessary. Informed consent is obtained in accordance with institutional policy, specifically including a discussion of the risks, benefits, and alternatives of the procedure. Patients generally receive moderate sedation or monitored anesthesia care. All patients should receive broad-spectrum intravenous (IV) antibiotic coverage according to institutional guidelines or preferences.

Procedure

Although typically not present in modern fluoroscopy suites, PTC is ideally performed on a tilting fluoroscopic table—another reason why these techniques have been largely supplanted by CECT and MRI. Because the specific gravity of contrast material is greater than that of bile, less contrast dye is typically required to fully delineate the biliary tree when the table is tilted.

Right-sided puncture

When performing a puncture of a right-sided bile duct, a site is selected in the right midaxillary line, typically one or two interspaces below the costophrenic angle. Needle puncture sites are ideally below the ninth intercostal space to avoid inadvertent crossing of the pleural space. The skin is prepped and draped using standard techniques and a subcutaneous anesthetic agent such as lidocaine is infused. A small dermatotomy is made with a No. 11 blade scalpel. A 21- or 22-gauge, 15- to 20-cm Chiba-style needle is advanced under fluoroscopic guidance superior to the closest rib to the target puncture site to avoid injury to an intercostal vessel or nerve. Real-time ultrasound guidance can be helpful for the initial puncture in the presence of bile duct dilatation. The puncture site and direction of puncture are chosen based on evaluation of the patient’s cross-sectional imaging studies ( Fig. 20.3 A–B). A small amount of water-soluble contrast agent is injected while slowly withdrawing the needle until a bile duct is identified. Injection of contrast agent into a bile duct has the appearance of oil being dropped in water. Inadvertent opacification of a vascular structure is recognized by the rapid clearance of the contrast agent. If a bile duct is not entered during withdrawal of the needle, the needle is reintroduced in a slightly different direction. It is generally considered best practice not to withdraw the needle completely from the liver to minimize the number of punctures through the liver capsule. When opacification of the biliary tree is challenging, particularly in the case of a nondilated biliary tree, the same puncture site may be used multiple times before selecting a new percutaneous access site. If successful puncture of a bile duct is unlikely from that site after multiple attempts, a new site should be chosen. In patients with biliary obstruction, gentle injection of 10 mL of iodinated contrast is typically sufficient for bile duct opacification. A larger volume of contrast material is typically required in nonobstructed systems. When the bile ducts are visualized, fluoroscopic images should be acquired and stored in multiple projections to identify specific portions of the biliary tree and to completely delineate abnormal findings, if present. Of note, care should be taken to avoid puncture of the gallbladder or an extrahepatic bile duct.

Success rate and accuracy

Percutaneous opacification of the biliary tree is successful in 95% to 100% of patients with biliary obstruction. ^{, ,} A success rate of 60% to 95% is reported for nondilated biliary systems. The likelihood of success in a nondilated system is increased by the number of needle passes performed. No current radiologic descriptions of obstructed bile ducts are pathognomonic for differentiation of benign and malignant disease. ^, Bile cytology and review of cross-sectional imaging can be helpful in conjunction with fluoroscopic images in diagnosing the cause of the obstruction.

Pitfalls in interpretation