Compare Combined Sphincterotomy and Balloon Dilation (ESBD) Versus Standard Sphincterotomy (ES) in Removing Biliary Stones

Study Overview
=================
Brief Summary
-----------------
To compare the technique of combined balloon sphincter dilation after an initial sphincterotomy and standard sphincterotomy in the endoscopic removal of large bile duct stones. The investigators hypothesize that combined balloon dilation and sphincterotomy allows for easier stone removal without added morbidities when compared to standard sphincterotomy.

Detailed Description
-----------------
Endoscopic sphincterotomy is a standard technique to enlarge the bile duct opening before stone removal during endoscopic retrograde cholangiopancreatography. However, complete sphincter ablation by endoscopic sphincterotomy is not always possible. Also, due to the tapering end of the distal duct, standard sphincterotomy may not be adequate for removal of particularly large stones. In a retrospective series by Ersoz et al, the addition of balloon dilation after sphincterotomy achieves a high stone clearance rate (89-95%). The investigators postulate that the combination of endoscopic sphincterotomy followed by balloon dilation may allow easier stone retrieval with acceptable complication rate.

Official Title
-----------------
Combined Sphincterotomy and Balloon Dilation (ESBD) Versus Standard Sphincterotomy (ES) in Removing Biliary Stones-a Randomized Controlled Trial

Conditions
-----------------
Common Bile Duct Stone

Intervention / Treatment
-----------------
* Procedure: endoscopic balloon dilatation
* Procedure: Standard sphincterotomy


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Patients at least 18 years old, presented to Prince of Wales Hospital for endoscopic retrograde cholangiopancreatography (ERCP) for known or suspected bile duct stones are invited to participate. Informed consent will be obtained before the beginning of ERCP. Patients are randomized to EST or ESBD after confirming the presence of bile duct stones on the initial cholangiogram Exclusion Criteria: septic shock, coagulopathy (international normalized ratio >1.3, partial thromboplastin time greater than twice that of control), platelet count <50,000x103/uL or ampullary tumors

Ages Eligible for Study
-----------------
Minimum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Standard sphincterotomy (ES)<br>After deep cannulation, a pull-type sphincterotomy will be performed with a 25mm sphincterotome (eg clever cut, Olympus, Tokyo, Japan) with division of sphincter up to the duodenal wall. A complete sphincterotomy is defined by the free passage of a fully bowed sphincterotome with a 25m wire and spontaneous bile drainage. | Procedure: Standard sphincterotomy<br>* Refer to under arms<br>|
| Active Comparator: Sphincterotomy plus balloon dilation (ESBD)<br>After complete sphincterotomy, a 3-cm long 15mm diameter CRE balloon is passed over a guidewire across the lower end of common bile duct. The contrast filled balloon is inflated to the size of the bile duct for around 30 seconds until waisting is abolished. | Procedure: endoscopic balloon dilatation<br>* Refer to description under arms<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| stone clearance rate at the index session | The ability to achieve complete stone clearance on the first ERCP | 24 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of ERCP's required to achieve stone clearance | The number of ERCP procedures required to achieve complete stone clearance in the bile duct | 3 months | 
| ERCP related complications | These include complications that were described in consensus published in 1991 | 30 days |