Cannulation of the biliary tree under endoscopic control with an echoendoscope,without fluoroscopy: report of a case series

Abstract

Introduction:

Endoscopic ultrasonography (EUS) is a validated technique allowing precise diagnosis and staging of pancreatic, biliary and ampullary disease. Developments in instruments and accessories have led to a more extensive use of this technology to perform operations. The use of EUS as an operative technique, alone or in conjunction with other endoscopic procedures, has already been described in the literature in several reports. However, despite the use of EUS, fluoroscopy has always been required to perform these operations. There are no data in the literature describing the feasibility, safety and efficacy of operative EUS in the treatment of common bile duct (CBD) obstruction, following a malignant or benign disease, performed completely under EUS guidance without fluoroscopic assistance.

Methods:

In this series we describe three cases of EUS treatment of CBD diseases performed without fluoroscopic assistance.

Results:

All the cases were treated by EUS without fluoroscopic assistance and no complications were encountered.

Conclusion:

Operative EUS without fluoroscopy appears to be a feasible technique. Its major advantages could be to shorten the examination time and to enable biliary or pancreatic operative endoscopy in patients in whom fluoroscopy could be dangerous, such as pregnant women. The endoscopist should have a good training both in EUS and endoscopic retrograde cholangiopancreatography. Prospective, larger studies are needed to confirm our preliminary data.

Introduction

Endoscopic ultrasonography (EUS) is a validated technique that allows precise diagnosis and staging of pancreatic, biliary and ampullary diseases. Developments in devices and accessories for EUS have led to a more extensive use of this technology to perform operative procedures in cooperation with, or as a substitute for, standard operative endoscopy.

Many authors consider therapeutics and operative procedures as the predominant indications for EUS in the future [Lobo et al. 1998; Giovannini et al. 2001]. The use of EUS as an operative procedure has indeed already been described in the literature in several cases in which the technique was used either alone or in conjunction with other endoscopic procedures, such as rendezvous drainage of obstructed biliary or pancreatic ducts [Bataille and Deprez, 2002; Lai and Freeman, 2005], ranshepatic cholangiography [Kahaleh et al. 2005], pancreaticogastrostomy [Tessier et al. 2007] and drainage of an obstructed common bile duct (CBD) [Burmester et al. 2003]. However, despite the use of EUS, fluoroscopic assistance has always been required to perform the procedures.

There are no data in the literature describing the feasibility, safety and efficacy of operative EUS in the treatment of common bile duct (CBD) obstruction, following a malignant or benign disease, performed completely under EUS guidance without fluoroscopic assistance. Here we describe three cases of therapeutic EUS for CBD diseases performed without fluoroscopic assistance.

Patients and methods

Three consecutive patients were treated between June 2009 and April 2010. All the procedures were performed by a single experienced endosonographer (more than 500 procedures per year) with previous training in endoscopic retrograde cholangiopancreatography (ERCP). All patients received prophylaxis with an intravenous antibiotic before the endoscopy which was performed under deep sedation (Propofol^®, AstraZeneca).

A linear convex EUS endoscope (Pentax–Hamburg: EG-3630U and EG-3830UT) was used in all the procedures. Cannulation was performed under endoscopic control with the instrument in the straight position in the second portion of the duodenum just minimally higher than the orifice of the papilla because the EUS instrument has oblique forward viewing. After cannulation the instrument was gently pushed down (nearly 1 cm) and the tip elevated to obtain a clear echographic picture of the papilla and CBD to confirm the selective cannulation of the duct.

Serum amylase, hemoglobin and white cell count were measured 6 and 24 hours after the procedures. Adverse events were defined according to consensus criteria for ERCP-related complications [Cotton et al. 1991].

Cases reports

Case 1

A 58-year-old man was referred to our center after an episode of jaundice. Transabdominal ultrasonography and computed tomography (CT) demonstrated CBD dilatation (13 mm) with gallbladder microlithiasis without evidence of CBD stones or malignancy. The patient underwent ERCP showing a distal CBD stenosis with backward dilatation. The stenosis was treated with endoscopic sphincterotomy and placement of a plastic stent (Tannenbaum 10 Fr, 7 cm; Wilson Cook). Brush-cytology of the CBD before stent placement was negative for malignancy and intrapapillary biopsies demonstrated low grade dysplasia.

EUS was performed 2 months after ERCP. The plastic stent was removed before the EUS procedure. EUS showed a normal pancreatic gland. The papillary region had a villous appearance due to thickening of the mucosal layer. This mucosal overgrowth was seen continuing into the CBD in a circumferential and irregular manner, causing an increase of wall thickness (3 mm) and stenosis of 15 mm in length. After the diagnostic EUS, the CBD was cannulated under EUS guidance using a sphincterotome. A 0.35 inch guidewire was passed and CBD brushings were collected. Finally, a plastic stent (CHBS 10-7 Cotton-Huibregtse; Wilson Cook) was placed. The CBD brushing performed under EUS guidance was diagnostic for adenoma with low grade dysplasia. The patient was referred for surgery.

Case 2

A 51-year-old man was referred to our center because of jaundice. CT showed a dilated CBD (1.2 cm) and pancreatic duct dilation to the papilla where a round lesion of 1.2 cm diameter was identified with enhancement after contrast injection. A 1 cm stone was found in the gallbladder.

EUS was performed demonstrating a normal pancreas. The CBD was markedly dilated (15 mm) with sludge and intrahepatic biliary tree dilatation. The papilla of Vater had a fibrotic appearance; EUS examination showed a small (1 cm) hypoechoic lesion with poorly defined borders invading the muscular layer of the wall. The ultrasonographic finding was highly suspicious of intrapapillary malignancy. After the diagnostic procedure, under real time EUS guidance, a Minitome (Cook Medical^®; Limerick, Ireland) was used to obtain access to the CBD. This device was chosen because of the small diameter (2.4 mm) of the working channel of the EUS scope (Pentax EG-3630U, Hamburg, Germany). A 0.18 inch guidewire was inserted and endoscopic sphincterotomy was performed. The sphincterotomy was sufficient to resolve the jaundice without stent placement. After the endoscopic sphincterotomy, papillary biopsies were performed which led to the diagnosis of adenocarcinoma. The patient underwent a Whipple procedure (pancreaticoduodenectomy) 1 week later.

Case 3

A 73-year-old man was referred to our center because of suspected CBD stones. CT was performed showing intra- and extrahepatic biliary dilation (CBD 12 mm). The CBD was interrupted behind the papilla because of a suspected stone. Magnetic resonance cholangiopancreatography confirmed the biliary tree dilation. The distal CBD wall had an irregular profile and the presence of stones was suspected. Neoplastic markers were negative. The patient underwent EUS which showed an apparently fibrotic papilla without evidence of bile flow from the papillary orifice. A dyshomogeneous hyperechoic lesion (diameter 12 mm) was observed in the retropapillary CBD, causing stenosis with initial CBD backward dilation up to 14 mm. Fine needle aspiration was performed and an adenocarcinoma was diagnosed. Under EUS guidance, the CBD was cannulated with a Mini-Tome over a 0.21 inch guidewire. Endoscopic sphincterotomy was performed to relieve pressure in the duct and the patient was referred to surgeons who carried out pancreaticoduodenectomy.

No procedure-related complications occurred in any of the three reported cases.

Discussion

EUS has had a history of continuous evolution from a diagnostic method to an operative technique. Different operative EUS procedures have been described in recent years and EUS-guided procedures are becoming a standard of practice in an increasing number of centers. Nevertheless some therapeutic procedures, such as the management of stones and palliation of biliopancreatic strictures, are still considered the field of ERCP. Only a small number of reports are present in the literature about the possibility of performing operative EUS as an alternative, in selected cases, to ERCP.

EUS is generally used only to gain access to the biliary or pancreatic duct system but, after that, the procedures are completed changing the scope or using the echoendoscope under fluoroscopic guidance [Chak, 2000; Giovannini et al. 2003; Sahai et al. 1998]. Until now there have been no studies in literature describing complete EUS-guided therapeutic procedures without fluoroscopic control.

A supposed limitation of using EUS in this clinical situation is strictly related to the oblique viewing of the EUS scope compared with the standard lateral view duodenoscope. Rocca and colleagues showed that ERCP performed with an echoendoscope eliminates the need for more than one intubation, with the related risks, and the need to use two sets of instruments, saving time and reprocessing resources. The average time for the combined procedure in their study was 27 minutes (9 minutes for EUS and about 20 minutes for operative endoscopy) [Rocca et al. 2006]. Moreover, the study also showed the feasibility of papillary cannulation by EUS without any delay with respect to a standard procedure. The clearance of the stones from the duct was completed under fluoroscopic control because of the mobility of the stones, which could have made them impossible to visualize by means of EUS only.

In our case series we confirmed the feasibility of endoscopic sphincterotomy with an echoendoscope and the capacity of EUS to confirm the right position of a device throughout a distal stenosis of the CBD or main papilla, without any need for fluoroscopic assistance.

Because EUS allows only a limited part of the CBD to be viewed, and thus to maintain the wire correctly in place inside the biliary tree and in order to deliver the stent correctly and safely, in the first case a Metro guidewire (Cook Medical^®; Limerick, Ireland) was used; therefore it was not necessary to use the torch and to move the scope to follow the whole CBD to check the wire or other accessories.

Using EUS guidance and gently pushing onward the probe after cannulation of the papilla, it is possible to visualize clearly the CBD, the distal stenosis and the accessory used on the same image, and to check intraductal exchange of any other accessories used and a possible final placement of a plastic or metal stent.

However, despite the feasibility of performing operative biliary endoscopy with an echoendoscope, there are some disadvantages. The oblique view of the scope makes endoscopic vision and cannulation of the papilla challenging, so improvements are desirable to overcome this problem. The rigid, long head does not represent, in our opinion, an obstacle to the use of this scope for biliary tree cannulation. It is hoped that, in the future, with the availability of new lateral view echoendoscopes with a bigger operative channel and a shorter ultrasonographic probe, it will be easier to perform operative procedures. It also seems important to stress that these procedures should be limited to distal and short stenoses. Other procedures, such as treatment of proximal stenoses and stone removal, must be performed with fluoroscopic assistance.

In conclusion, an EUS-guided technique without fluoroscopy appears to be feasible. Its major advantages could be to shorten the examination time and enable biliary or pancreatic operative endoscopy to be performed, only in selected cases, in patients in whom fluoroscopy could be dangerous such as pregnant women and patients in intensive care units. Before performing these procedures, the endoscopist should have a good training both in EUS and ERCP. Prospective, larger studies are needed to confirm our preliminary data.