Percutaneous biliary interventions

Access and Diagnostic Stage

Biliary access is performed under fluoroscopic or ultrasound guidance. Right-sided access is usually performed along the mid-axillary line just above the 10th rib, while left-sided access is performed under ultrasound guidance.

• Puncture technique: A coaxial system with a 21-G Chiba needle is used. This allows a smooth transition from a fine guidewire (0.018 inch) to a working guidewire (0.035 inch), minimizing trauma.
• Aspiration: The obtained bile must be sent for culture to select targeted antibiotic therapy in the event of cholangitis or sepsis.
• Cholangiography: Performed with iodinated contrast. Peripheral ducts are always chosen for puncture, as manipulations on central branches carry a high risk of damaging major vessels at the porta hepatis.

If the cause of the obstruction is unclear, forceps or brush biopsy of the stricture is used to clarify the diagnosis, and the bile is sent for cytologic examination.

Biliary Drainage and Stenting

Depending on the clinical picture, temporary or permanent bile diversion is chosen. External drainage leaves the catheter above the obstruction zone, but internal-external drainage is preferred, where a drainage tube with side holes is passed through the stricture into the duodenum.

Types of biliary stents:

1. Plastic: Require a wide percutaneous tract (10–12 F), which is painful for the patient. They quickly become encrusted with bile and lose patency, but are easily removed. Ideal for preoperative preparation.
2. Metal: Inserted in a compressed state through a narrow channel (6–8 F) and self-expand. They have good patency but cause a fibrous reaction. Contraindicated in benign conditions and prior to surgical treatment.
3. Covered stents: Have a tissue sheath that prevents tumor ingrowth. Their disadvantage is the risk of migration and occlusion of side branches, which can provoke cholecystitis or pancreatitis.

In malignant hilar tumors, stents are placed in complex configurations (T-, H-, or Y-shaped) to drain both lobes. Following metal stent placement, balloon dilation is required—an extremely painful procedure demanding adequate analgesia.

Management of Benign Diseases

Benign strictures most commonly result from iatrogenic injuries (e.g., during laparoscopic cholecystectomy), ischemia after liver transplantation, or primary sclerosing cholangitis.

Treatment consists of balloon dilation of the stricture up to 10 mm. After dilation, the drainage catheter is left in place across the stricture for at least 2–6 weeks. Metal stents are not used here due to their inevitable occlusion within a few months.

A particular challenge is strictures of biliodigestive anastomoses (e.g., after Roux-en-Y reconstruction). Due to altered anatomy, endoscopic access is impossible, making percutaneous intervention the method of choice.

Cholelithiasis and Calculus Removal

Although endoscopy remains the primary method for common bile duct stone removal, percutaneous access is indispensable when ERCP fails or stones are located intrahepatically.

Extraction methods:

• Balloon pushing: The catheter is advanced past the stone, inflated, and pushes the stone into the duodenum (requires caution due to the risk of pancreatitis).
• Rendezvous technique (Rendezvous technique): A guidewire is introduced percutaneously through the liver into the bowel, where it is captured by the endoscopist for further manipulations from below.
• Through the T-tube tract: If a drainage tube is present after cholecystectomy, a 6-week waiting period is observed to allow a firm tract to form. Stones are then extracted along the guidewire using a specialized basket.

Complications and their prevention

Procedure-related mortality is about 2%, but 30-day mortality exceeds 10% due to the severity of the underlying oncological disease.

Frequent complications include pain, bile leakage, bleeding (haemobilia), and septicaemia. Pancreatitis may occur during manipulations in the area of the sphincter of Oddi, while accidental pleural transgression can lead to haemothorax or pneumothorax.

To prevent bleeding and pleural effusion, embolization of the puncture tract is performed at the end of the intervention. A hemostatic sponge (Gelfoam) or a glue mixture of lipiodol and cyanoacrylate is introduced into the tract.

Briefly: answers to topical questions

Class and exam questions

What else to study on this topic

• Stenting configurations for hilar tumors (Y-, T-, and X-shaped).
• Rendezvous technique in complicated choledocholithiasis.
• Technique of balloon dilation of biliodigestive anastomosis strictures.
• Differences in stent occlusion mechanisms: tumor ingrowth and tumor overgrowth.
• Materials and methods for transhepatic tract embolization.

Other topics in the "Interventional radiology" section

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