Despite being practiced for more than 40 years, the technique of ERCP for the treatment of Bardock stones has not been standardized. Therefore, the procedure can be challenging and protracted. We have proposed a protocol for the efficient and effective management of Bardock stones at ERCP. The majority of stones in the Bardart can be extracted at ERCP with standard manoeuvres such as biliary sphincterotomy and balloon extraction. These standard manoeuvres will be described in this video. The Bardock is first successfully cannulated and the cladogram revealed a free floating stone in the proximal Bardock. A biliary sphincterotomy was then performed. The tip of the sphincter tome is inserted inside the Bardock. The sphincter tome is then flexed slightly and a sphincterotomy is performed in the 11 o'clock orientation up to the junction between the major papilla and the duodenal fold. The stone is then removed using a stone retrieval balloon. However, some stones can be challenging. While every clinical scenario cannot be anticipated, following evidence-based principles can help with the management of the majority of difficult Bardock stones. In this patient, a cladogram revealed several large Bardock stones. Taking this patient as an example, we will now go through the algorithmic management of Bardock stones. When stones are seen at cladogram, the most important question that each endoscopist must ask is whether advanced endoscopy techniques are required, namely the need for balloon sphincteroplasty and the need for lithotripsy. The importance of these questions have been addressed in a prior randomised trial by our group and an algorithmic approach to the management of Bardock stones has been developed. A balloon sphincteroplasty must be performed when the tapered Bardock is seen, which is defined as the size of the distal Bardock one centimetre above the ampullary orifice being less than 50% the size of the extraopathic Bardock in its largest dimension. Lithotripsy may be needed based on the stone-duct ratio, whereby the size of the largest stone exceeds the size of the bile duct distal to the stone. The size of the duodenoscope is first measured to be the reference standard. Subsequently, the size of the largest stone and size of the duct distal to the stone are measured to calculate the stone-duct ratio. Then, the size of the extraopathic duct in its largest dimension and the size of the duct one centimetre above the ampullary orifice is estimated to determine whether the distal duct is tapered or not. In this particular case, the distal duct was not tapered and the stone-duct ratio was less than 1 and hence a determination was made to proceed with an ERCP adopting the standard technique. After performing a sphincterotomy to the duct-judinal junction, stone extraction was commenced. Stone extraction is then performed and must begin with the distal-most stone. The technique of stone extraction involves positioning the fully inflated 15mm extraction balloon above the stone. The big wheel of the duodenoscope must be fully deflected down and then the duodenoscope must be clockwise and then gently advanced inwards in the axis of the bile duct. The objective is not to pull the stone out but rather to have the balloon and the duodenoscope extract the stone using its own gravity. This prevents balloon tears and minimises the possibility of ductal perforations. The more proximal stones are then removed one after the other. Also, it is important to irrigate the bile duct with saline to remove any residual debris and to minimise stone recurrence. In this patient who presented with abdominal pain and elevated liver tests, the clangogram reveals a distal bile duct that is narrowed. The extrahepatic duct and its widest area is now measured. As the distal bile duct above the ampullary orifice measures less than half the widest portion of the extrahepatic duct, this patient is deemed to have a tapered bile duct. Also, the stones are large in size and are unlikely to be extracted successfully through the tapered distal duct using the standard techniques. Therefore, a maximal biliary sphincterotomy is undertaken and a balloon sphincteroplasty is performed. The size of the balloon should not exceed the maximum size of the bile duct. Also, prior to balloon dilation, it is important to dislodge any stones in the distal bile duct more proximally so as to avoid an inadvertent ductal perforation by compressing the stone against the duct wall. Once balloon sphincteroplasty is completed, the large stone can be extracted successfully using a stone retrieval balloon. This patient underwent an ERCP for bile duct stones. The bile duct was first cannulated, and the clangogram revealed multiple impacted stones with duct to stone mismatch with stone-to-duct ratio exceeding 1.1, and a tapered distal bile duct. After performing a biliary sphincterotomy, balloon sphincteroplasty of the distal bile duct was performed first due to the tapered bile duct, and then stone removal was attempted using a basket. However, the basket, although able to be passed proximally, cannot be opened adequately to capture the stone. This is due to the large stone size impinging on the catheter and precluding the basket from opening completely. These patients typically have stone-to-duct ratio exceeding 1.1, and will almost always require clangoscopy-guided lithotripsy. Subsequently, this patient underwent single-operated clangoscopy-guided electrohydraulic lithotripsy of the large bile duct stones. Once the stones have been adequately fragmented, they can be removed using a stone retrieval balloon or baskets. This patient was referred for extraction of bile duct stones after failed ductal clearance at an outside facility. As evident on this clangogram, there was only a mild stone-to-duct mismatch in this patient, with ratio of 1.06. In this situation, mechanical lithotripsy is possible only when the catheter sheath can be easily passed to the proximal bile duct and the basket opened adequately for stone capture. As the patient also had a tapered distal duct, balloon sphenotroplasty was performed. The mechanical lithotripsy basket was then introduced into the bile duct and then opened proximal to the stones. A gentle shaking motion of the basket allows the stones to be captured inside the basket, which is then closed to fragment the stones. The stone fragments can then be easily removed, either using the basket or a stone retrieval balloon. The final clangogram shows complete ductal clearance. In rare instances, if the stones are very large, exceeding 4 cm in size, more than one endoscopic session may be required in conjunction with long-term biliary stenting to achieve treatment success. The proposed protocol was validated prospectively in 260 patients, of whom 20% had a tapered bile duct or stone-duct mismatch. The proposed approach enabled efficient single-session ductal clearance with overall success rate of 99.6%.

protocol

Bardock stones

endoscopic retrograde cholangiopancreatography

ERCP

stone extraction