The first reports of EUS-guided cholangiography appeared in 1996. The first EUS-guided stent placement was reported in 2001, while the first EUS-guided bilirirandevu was reported in 2004. Since then, in the last one decade, a considerable amount of literature has accumulated about this procedure. EUS-BD can be defined as endoscopic procedures utilized for placement of biliria endoprosthesis under EUS guidance. EUS may be used for the entire procedure or it may be used partially to achieve selective biliria access as in randevu. The potential advantages of EUS-BD include the possibility of accessing the biliria system at multiple points, either from the stomach or from the duodenum, thus duodenal obstruction is not an issue and since the biliria access is away from the papilla, there is potential for low post-procedure pancreatitis. The indications for EUS-BD include patients who have obstructive jaundice and either have duodenal stenosis or have a failed ERCP attempt. Patients with difficult cannulation can also undergo EUS-guided randevu procedure. Depending on the access and the exit of the stent, there are multiple variations of EUS-BD. For example, if the access is transhepatic and the exit is transluminal, it is a hepatogastrostomy. If the access is transhepatic and the exit is transpapillary, it is called as antigrade procedure and transduodenal transluminal procedure includes choledochoduodenostomy. Patients in whom EUS is used just for biliria access for ERCP completion undergo a randevu procedure. The basic steps for EUS-BD include choosing an appropriate puncture site in the stomach or the duodenum, utilizing Doppler to identify intervening blood vessels, puncturing the bile duct with a 19-gauge needle, passage and manipulation of the guide wire, dilation of the track and finally stent placement. The instrumentation includes a linear therapeutic echo endoscope, a 19-gauge EUS FNA needle, wires of O35, O32 or O25 gauge, dilators which may include a biliary balloon dilator, a 6.5 inch cystotome or a 5-inch stiff catheter and finally biliary plastic or metal stents. Recently dedicated metal stents have become available for EUS-BD. The indications for EUS guided choledochoduodenostomy include patients who have obstructive jaundice and have a stenosis in second part of duodenum or those who have failed ERCP attempts. Scope positioning is the most important step for success of this procedure. In this patient as you can see we are positioning the scope in D1, D2 area. The scope should be in the long loop position and the tip should be looking towards the hilum so that you have a longitudinal view of the bile duct. Doppler is applied here to see that there are no intervening blood vessels. Bile duct puncture is done with a 19-gauge needle. The scope tip is kept approximated to the bile duct and a gentle push is made. Bile is aspirated to confirm correct entry and then contrast is injected to evaluate the bile duct anatomy. Guide wire can go towards the hilum or towards the papilla and hence a scope position is extremely important. Also it is important to be able to torque the wire in the required direction. Here you can see in this case the wire first went towards the papilla but then was torqued to go into the right hepatic duct. Decent length of the wire should be left inside for placement of a stent. If the wire does not go well then a 5-inch stiff catheter can be utilized to position the wire appropriately. You can see in this case a 5-inch catheter is being utilized to position the wire appropriately. Once the wire is in place, track dilation can be done with a 6.5 francistotone or with a biliary balloon as was done here. You can see a biliary balloon under endosonography, a double hyperechoic line is seen traversing the duodenum and into the bile duct. Usually a 4 mm biliary balloon is used and the track is dilated to about 7 francs. We utilize either a plastic stent or a covered metal stent for choledochodeiodonostomy. A covered stent is utilized to prevent biliary leak. It is important to see that the cystic duct insertion is not blocked by the covered stent. Here you can see an ultrasonographic view of an expandable stent being deployed. It is important to realize that there is little space in the D1, D2 area for scope maneuvering. So scope maneuvering has to be gentle and careful. The stent is being deployed here and as you can see gentle movements of the scope are being done to deploy the stent. The endoscopic view shows you the constraint of space here. You can see the endoscopic view at the D1, D2 junction and here the stent is fully deployed. The X-ray shows a nice air cholangiogram. There are two types of transhepatic stentings depending on the exit route of the stent. In hepatoecogastrostomy, the stent exits into the proximal stomach, while in anti-grade procedure, the stent exits across the papilla into the duodenum. Anti-grade procedure resembles the percutaneous biliary drainage procedure the most. Indications include patients with type 1 hylar block, patients with malignant distal biotech block, and patients with post-operative anatomy like post-ripple surgery or post-Bilroth II resection. The steps include positioning the scope in the proximal stomach, puncturing the stomach with a 19-gauge needle, wire manipulation across the hylum and across the papilla into the duodenum, tract dilation. Now if the wire successfully passes across the papilla, anti-grade stent placement is done. If the wire doesn't pass across the papilla and remains in the bile duct, a hepatoecogastrostomy is done. As mentioned earlier, scope position is vitally important for a successful procedure. The scope can be positioned in line with a B2 radical as seen here, or a B3 radical as seen here. B2 radical appears okay for a rendezvous procedure, but for a stent placement, a B3 radical is preferred because the stent exit in case of a hepatogastrostomy should be in proximal stomach and not in the esophagus, which can happen with a B2 radical. If an EUSBD is being performed in a patient with a hyalur block, it is prudent to use an air cholangiogram instead of contrast injection, as is being done in this case. A prior MRCP examination gives a detailed road map, and we currently do EUSBD in only type 1 hyalur block. Guide wire manipulation from transhepatic route can be tricky because you have to manipulate the wire across the hyalum and then attempt to manipulate it across the papilla into the duodenum. Several tricks can be employed to successfully negotiate the wire across the papilla. The ability to torque the wire is extremely useful in tricky situations. In this patient, as you can see, the needle is entering almost perpendicular to the bile duct radical and an acute angle is formed. Here, torquing the wire allows us to put the guide wire in the right position into the hyalum and then across. Another trick is to use a stiff catheter or a systatome to stabilize the wire in a dilated system. As will be seen in the next case, sometimes the wire loops in different locations and in these cases, a catheter, a 5-frame stiff catheter can be inserted to stabilize and prevent looping of the wire and allowing it to pass in the desired direction. As you can see in this case, after contrast injection, you see a distal CBD block. A wire passes nicely initially across the papilla but then takes a loop in the liver which is stabilized using a systatome. Once the wire has gone into the duodenum, the stiff catheter or a systatome is pushed across the papilla into the duodenum and contrast is injected. The wire is then replaced with a stiff wire and stenting is done. Uncovered expandable stents are okay for anti-grit procedures because this is just like an ERCP procedure and there is no trans-luminal stenting in anti-grit procedure. It is extremely important to know where the papilla is to allow the precise length of stent into the duodenum. This is done by contrast injection into the duodenum and into the stent. If it is not possible to manipulate the wire across the papilla into the duodenum then a hepatic gastrostomy can be performed as a salvage procedure. At many centers hepato-gastrostomy is also performed as a primary procedure. The first step as in all procedures is careful inspection with Doppler and needle puncture with a 19 gauge needle. Here you can see the needle puncturing a biliary radical in the left lobe of the liver. After aspirating bile contrast is injected to delineate the bile duct anatomy. In this case we are using a 025 Viziglide and you can see by torquing the wire is maneuvered into the common bile duct but has not gone across the papilla. The wire is left in the bile duct and then tract dilation is done first using a 5-inch catheter and then with a biliary balloon. You can see the catheter in this picture. Now a biliary balloon is being inserted for dilating the tract. The balloon can be seen on an EOS picture also, a 4 millimetre biliary balloon is used. A stent is then inserted, a variety of stents are available for a petrogastrostomy, some of them are partially covered outside and uncovered inside to prevent the blocking of the side branches of the bile duct radicals and also to prevent bile leak from the anastomosis. Positioning of petrogastrostomy stent has to be done carefully because the puncture is usually in the proximal stomach and you should leave a longer length of the stent into the stomach to prevent migration of the stent entirely into the bile duct. Physical positioning of the stent is done and about 3 to 4 centimetres of the stent is left within the stomach lumen. You can see here the stent is being carefully deployed now. In this patient as you will see on endoscopy picture, the puncture is just beyond the GE junction. So, there was a possibility of the stent opening into the distal esophagus which was prevented by pushing the stent into the stomach after deployment. Here is the endoscopic view of the deployment. You can see that the stent is being deployed at the cardiac and then being pushed inside. A longer length of stent is kept about 3 to 4 centimetres and then it is pushed down into the stomach and nice flow of bile is seen. EUS guided rendezvous procedure differs from the other procedures described before in that it is just an access procedure allowing us selective bile duct access. So the indications are patients who have obstructive jaundice with an approachable papilla and a failed ERCP. If both transhepatic and transduodenal routes are available for rendezvous, which route is better? We have shown that transduodenal access is safer although transhepatic and transduodenal access both have similar success rates. A good scope position is critical to the success of rendezvous. In this patient we have kept a long scope position with the scope tip looking towards the papilla. This allows for a very easy passage of wire down across the papilla. In this case on the other hand we are puncturing at right angles. As you can see, the needle is looking towards the hylum. So you will need torquing of the wire to allow the wire to come down towards the papilla and not selectively go towards the hylum. This becomes rather difficult. Again in this case, the needle is looking towards the hylum and you can see that torquing is required. Initially, the wire goes towards the hylum and then by torquing it, we can bring it down out of the papilla. Once the wire is out of the papilla, it is pushed into the third part of the duodenum and several loops are made. After that, the echo endoscope is carefully withdrawn leaving the wire in place. We use a short 260 centimeter wire and to keep that wire in position, we inject sterile saline with the syringe into the needle. Once the echo endoscope is out of the mouth, the wire is grasped carefully and a duodenoscope is inserted by the side of the wire. Care should be taken to insert the duodenoscope in such a way that it does not entangle with the wire. Once we have reached the papilla, the wire can be seen exiting from the papilla and this is the real rendezvous, the meeting point of two techniques, EOS and ERCP. We are using a snare to catch hold of the wire and then pull it into the biopsy channel of the duodenoscope. The snare is fully open and the wire is carefully withdrawn till it is held by the snare. To prevent accidental dislodgement of the wire, the wire is also fed at the same time from the mouth. We use a baby forceps to help push the wire down the esophagus and stomach while simultaneously pulling it out from the duodenoscope biopsy channel. This is a concerted coordinated action and requires extreme care. Here you can see the biopsy forceps going into the stomach. A sphincter tome is then threaded over the wire and ERCP is completed in the usual fashion. Patients who undergo rendezvous procedure usually have failed ERCP because of distorted anatomy in the region of the papilla. Hence ERCP is usually difficult. Maintaining duodenoscope position in front of the papilla is essential and needs care. A sphincter tome is being done right now. As you can see maintaining the position, scoping position is difficult in this case and we have to make repeated adjustments in the scope position to keep it in place. After completing the sphincter tome, a stent is being inserted. Again scope position is very important and repeated manoeuvres have to be done to keep the scope in position so that it does not slip out of the duodenum. Wire exchange can be cumbersome and time consuming, hence we usually first attempt to cannulate by the side of the wire exiting from the papilla. It succeeds in about 60 to 70% of cases. Here you can see a cannulation being attempted by the side of the exiting guide wire. At times entering the papilla could be difficult and a pre-cut over the wire can be done to facilitate entry into the bile duct. We are into the bile duct now as you can see here and ERCP can be completed in the usual fashion. Shearing of the sheath of the wire can happen during EUSBD. This is usually because of the sharp edge of the EUSFNA needle. This can be prevented by carefully advancing or withdrawing the guide wire into the needle. Sudden withdrawal or sudden advancement of the wire usually results in shearing. Recent studies have shown that EUS rendezvous has an acceptable success rate and morbidity. The success rate is in excess of 80% and the complication rate is around 12%. Complications include perforation, sepsis, pneumoperitoneum and abdominal pain. EUSBD on the other hand also has shown decent success rate in the recent literature varying from 86 to 92%. The complication rate varies from 8.6 to 20.6%. A small randomized trial has shown that EUSBD and PTBD have equivalent outcomes. Larger studies are required. A large multicenter retrospective study has shown that EUSBD and ERCP have equivalent results for malignant distal blocks. Prospective studies are needed. What are the complications of EUSBD? The complications can be because of a misplaced or displaced tract dilation or stent which include perforations, peritonitis, leaks, collections or stent migrations. Inadequate drainage can lead to infection and sepsis while a ruptured blood vessel can give rise to bleeding. Perforations or leaks can happen in 0 to 3% of cases. To the left you are seeing a CT scan of a patient with a bile duct leak because of a migrated hepatogastrostomy stent. To the right you are seeing a large perforation because of inward migration of hepatogastrostomy. These patients are usually managed conservatively although rarely surgery may be required. Prospective studies have shown that the use of needle knife is associated with perforations and leaks. Hence, a needle knife should not be used for tract dilation. There is some data to suggest that plastic stents are associated with higher leaks following EUSBD. However, this needs to be corroborated in large prospective studies. In conclusion, EUSBD appears to be a promising and viable option for biliary drainage. This is especially true in patients with reordinance genosis or postoperative anatomy. EUS rendezvous is a useful technique in patients where ERCP fails and the papilla is approachable. We need large prospective and randomized studies to determine the exact role of EUSBD.

EUS-guided biliary drainage

EUS-BD procedure

endoscopic ultrasound guidance

bile duct stent placement

obstructive jaundice

endoscopic retrograde cholangiopancreatography (ERCP)

EUS-guided rendezvous procedure