Discussion of Biliary EUS-FNA

What kind of biliary lesion is suitable for EUS-FNA？

1. Lump/nodule of bile duct grows outward.

2. Thickening of bile duct wall >=3mm in theoretical consideration

When EUS-FNA is required after ERCP failed, if no effective percutaneous bile duct drainage is established, puncture of the bile duct wall may cause bile leakage.

To determine whether bile duct EUS-FNA is performed, the below questions need to be asked:

1. Sufficient EUS-FNA experience is required.

2. The cyto pathological diagnosis rate of EUS-FNA in the hospital.

3. What is the diagnostic rate of brush/biopsy in the hospital?

4. Can ERCP bile duct drainage or PTCD be performed timely after EUS-FNA?

How to develop EUS - BD/PD?

EUS - BD/PD

EUS-BD/PD is “the pearl in the crown” for interventional diagnosis and treatment.

It is the remedy after the failure of ERCP/PTCD. In China, it could not be treated as a first choice diagnosis and treatment because the technique develops late in China. At present,

EUS-BD/PD could only be carried out in some large medical centers.

EUS – BD vs PTCD

According to our experience, the comparison is been done in the below aspects:

Treatment success rate: higher

Adverse events: less

Re-intervention rate: lower

EUS - BD vs. ERCP

Treatment success rate: the same rate of stent blockage

Reinterventional rate: EUS-BD >ERCP

Generally speaking, EUS-BD in China is not well developed as ERCP. It is lacking in training and its specially used accessories. The techniques for EUS-FNA include guide wire exchange,guide wire selection, expansion, stent placement. The complications are more serious and with higher occurrence than ERCP. And these complications are more difficult to handle.

The situations which EUS-BD/PD is not recommended:

EUS-BD/PD is not recommended

1.   Indications are not clear. 

   2. There are contraindications, for example clotting disorders, etc.  3. Patients/family members do not understand.  4. No surgical support.  5. No interventional support 6. Don't do it without adequate preparation. 7. Evaluate the benefit and risk. 8. Don't induce patients to choose the operation.

Details of EUS-BD:

1. Puncture

Selection of puncture needle and guide wire: 19G, 0.025 inch or 0.035 inch.

A 22G needle can only apply with 0.018 inch of wire, which is very thin and soft, and needs to be replaced with a thicker wire to facilitate stent placement.

Selection of intrahepatic bile ducts:

In general, intrahepatic bile duct puncture is the best choice for the third liver segment, but sometimes it is very difficult. The bile duct of the second liver segment or the fourth liver segment may be selected, and meditational puncture should be avoided for the bile duct of the second liver segment. Titanium clip labeling at the gastroesophageal junction is a good method.

Puncture direction: to enter with the guide wire

Keep the same direction and avoid repeated back-and-forth of the guide wire. Guide wire back and forth may easily cause the hydrophilic tip part to split or break.

With successful puncture, but failure in subsequent operation may also lead to the

biliary leakage.

When there is no full confidence, avoid multiple puncture of extra hepatic bile duct through duodenum. Even if the puncture of bile duct is only once but the subsequent operation fails, timely PTCD is also recommended

The normal liver parenchyma during trans-hepatic puncture can help to compress the puncture path and may reduce the chance of biliary leakage.

2.    Stent usage in EUS-BD:

Plastic stent does not have dilating tension, bile is easy to leak along the stent

Double pigtail bracket: it is difficult to insert when the tip is bent and the puncture path is not expanded sufficiently

Covered biliary metal stent is easy to migrate.

Nasal bile duct: it is easy to be torn off by the patient, resulting in bile leakage.

The generally used approach is to insert a metal stent for the biliary tract.

3.    EUS-guided hepaticogastrostomy (EUS-HGS)

EUS-guided hepaticogastrostomy (EUS-HGS) for the creation of a fistula between the stomach and the left intrahepatic bile duct is an EUS-guided biliary drainage technique. Although EUS-HGS has a high technical success rate of 87%, its procedure-related adverse event rate of 27% was reportedly higher than the rates of other EUS-guided biliary interventions.

When the semi-coated metal stent is used, the uncoated part with a length of 1cm at the end is placed in the intrahepatic bile duct to reduce the possibility of stent migration and prevent the blockage of part of intrahepatic bile duct branches, resulting in cholangitis. The length of the stent should be at least 10cm or even 12cm. The movement between the liver and the stomach is easy to cause the displacement of the stent, while the long stent is not easy to migrate.