Can Endoscopic Ultrasound Help to Drain the Gallbladder?

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Gastrointest Interv 2013; 2:30–35

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Gastrointestinal Intervention

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Review Article Can endoscopic ultrasound help to drain the gallbladder?

Jun-Ho Choi, Do Hyun Park,* Sang Soo Lee, Dong-Wan Seo, Sung Koo Lee, Myung-Hwan Kim

abstract

Percutaneous transhepatic gallbladder drainage (PTGBD) is a less invasive standard procedure to decompress the inﬂamed gallbladder in patients who are at high risk for emergency cholecystectomy. Recently, endoscopic ultrasonography-guided transmural gallbladder drainage (EUS-GBD) has been proposed as an alternative effective treatment modality for the management of acute cholecystitis in high-risk patients. EUS-GBD includes EUS-guided nasogallbladder drainage, gallbladder aspiration, and gallbladder stenting via a transmural endoscopic approach. Several investigators have reported high technical success with acceptable complication rates. Further prospective evaluation of the feasibility, safety, and efﬁcacy of EUS-GBD will help identify the most suitable indications for this procedure. This article is a detailed review of the use of EUS for gallbladder drainage, with an emphasis on its technical aspects. Copyright Ó 2013, Society of Gastrointestinal Intervention. Published by Elsevier. Open access under CC BY-NC-ND license.

Keywords: Cholecystitis, Endoscopic ultrasonography, Gallbladder, Radiological procedure

Introduction alternative approach for the management of acute cholecystitis in – high-risk patients (Table 1).22 27 The potential benefits of EUS- Although laparoscopic cholecystectomy is the treatment of GBD are that it is a one-stage procedure after the transpapillary choice for patients with acute cholecystitis, this procedure is un- approach and avoids long-term external drainage in cases in suitable for patients of advanced age or with advanced malignancy which external drainage catheters cannot be internalized. This – or underlying comorbidity.1 5 Currently, nonsurgical gallbladder article describes the indications, techniques, and outcomes of drainage is performed through percutaneous and endoscopic published data on EUS-GBD. drainage procedures. Percutaneous transhepatic gallbladder drainage (PTGBD) has been considered the preferred method for Indications for EUS-GBD several decades in patients with high surgical risk, with clinical – response rates of 78–100%.6 11 Despite its usefulness, the percu- EUS-GBD can be considered if patients are not thought to be taneous drainage procedure has several drawbacks, including a candidates for cholecystectomy because of their underlying co- – postprocedural adverse event rate of 0.3–12%.6 10,12 PTGBD may be morbidity, poor surgical performance (American Society of Anes- contraindicated in patients with massive ascites or severe coa- thesiologists Physical Status Classification System score of IV or V), gulopathy. In addition, percutaneous drainage catheters cause or advanced malignancy after an unsuccessful transpapillary cystic patient discomfort, and are related to inadvertent catheter approach. For patients who have previously undergone unsuc- removal or migration. Endoscopic gallbladder drainage includes cessful endoscopic retrograde cholangiopancreatography (ERCP) transpapillary gallbladder drainage with nasobiliary drainage via a transpapillary cystic approach, EUS-GBD can be considered. To (ENGBD), transpapillary gallbladder stenting, or endoscopic avoid complications, it is also important to select patients with ultrasound (EUS)-guided transmural gallbladder drainage adequate adherence between the inflamed gallbladder wall and the – (EUS-GBD).13 20 Endoscopic transpapillary gallbladder drainage is adjacent gut wall under the EUS window. Transmural gallbladder subject to low technical success rates due to nonvisualization of drainage has several potential advantages over the transpapillary the cystic duct on the cholangiogram or failure of guide wire approach, including avoidance of ERCP-related pancreatitis. The cannulation through the cystic duct into the gallbladder.14,16,18,21 transmural approach is not limited by the shape of the cystic duct In this circumstance, EUS-GBD is gaining favor as an effective or inaccessible papilla.

Division of Gastroenterology, Department of Internal Medicine, University of Ulsan, College of Medicine, Asan Medical Center, Seoul, South Korea Received 5 March 2013; Accepted 15 March 2013 * Corresponding author. Department of Internal Medicine, University of Ulsan, College of Medicine, Asan Medical Center, 88, Olympic-Ro 43-Gil, Songpa-gu, Seoul 138-736, South Korea. E-mail address: [email protected] (D.H. Park).

2213-1795 Copyright Ó 2013, Society of Gastrointestinal Intervention. Published by Elsevier. Open access under CC BY-NC-ND license. http://dx.doi.org/10.1016/j.gii.2013.04.004 Jun-Ho Choi et al. / EUS-guided transmural gallbladder drainage 31

Table 1 Summary of Previous Reports on Endoscopic-ultrasound-guided Transmural Gallbladder Drainage

Author (y) Type of No. of Drainage Technical Functional Complication Proﬁles of postprocedural study cases success success adverse events Kwan et al (2007)26 R 3 Double-pigtail stent/nasocystic 3/3 (100) 3/3 (100) 1/3 (33.3) Bile leakage drainage tube Baron et al (2007)27 R 1 Double-pigtail stent 1/1 (100) 1/1 (100) dd Lee et al (2007)25 P 9 Nasocystic drainage tube 9/9 (100) 9/9 (100) 1/9 (11.1) Pneumoperitoneum Song et al (2010)24 P 8 Double-pigtail stent 8/8 (100) 8/8 (100) 3/8 (37.5) Bile leakage, pneumoperitoneum, and stent migration in each case Jang et al (2011)22 P 15 Modiﬁed CSEMS 15/15 (100) 15/15 (100) 2/15 (13.3) Pneumoperitoneum (2) Jang et al (2012)23 P 30 Nasocystic drainage tube 29/30 (96.7) 29/30 (96.7) 2/30 (6.7) Pneumoperitoneum (2)

Data in parenthesis are presented as %. CSEMS, covered self-expandable metal stent; P, prospective; R, retrospective.

Procedure of EUS-GBD used in EUS-GBD. First, metal stents can seal the gap between the stent and the fistula tract by expanding, thereby reducing the risk There are various approaches and different types of devices with of bile leakage.22 Second, modified metal stents have been different effects on drainage. We describe in detail our preferred designed to avoid the risk of migration and biliary leakage by technique using a conventional therapeutic linear echoendoscope enlarging the flares at the end of the stent 90 (BONA-AL stent)22 (Fig. 1). or by means of bilateral anchor flanges to ensure lumen-to- The gallbladder is usually visualized from the prepyloric lumen apposition (AXIOS; Xlumena Inc., Mountain View, CA, – antrum of the stomach or duodenal bulb using a linear-array USA).29 31 Third, metal stents are larger in diameter than plastic echoendoscope (GF-UCT240-AL; Olympus Optical Co., Ltd., Tokyo, stents.22,30 Thus, metal stents may facilitate draining of thick or Japan) with fluoroscopic guidance. The puncture point usually necrotic debris in the acutely inflamed gallbladder. Fourth, metal corresponds to the gallbladder neck or body. A 19-gauge needle stents can be reconfigured if the outer sheath of the delivery (EUSN-19-T; Cook Endoscopy, Winston–Salem, NC, USA) is inser- device is not fully deployed.22 This may allow the endoscopist to ted into the gallbladder under EUS guidance, after confirming the adjust the position of the stent, thereby avoiding unnecessary absence of intervening vessels. Bile is aspirated, and contrast repuncture. medium is then injected to obtain a cholecystogram. A 0.035 inch guide wire (Jagwire; Microinvasive Endoscopy, Boston Scientific EUS-guided gallbladder aspiration Corp., Natick, MA, USA) is passed through the needle and coiled in the gallbladder. After removal of the EUS needle, a 6F or 7F bougie EUS-guided gallbladder aspiration (EUS-GBA) is a simple (Soehendra Biliary Dilatation Catheter; Cook Endoscopy) is inserted procedure that does not require the placement of a nasobiliary to dilate the fistula tract. If there is resistance to the advancement of catheter or stent. EUS-GBA can be carried out repeatedly if the bougie catheter, a triple-lumen needle-knife (Microtome; Bos- the first attempt is unsuccessful. EUS-GBA can be performed ton Scientific Corp.) with a 7F shaft diameter is minimally used to without severe complications, because smaller EUS needles are dilate the tract by applying a brief burst of pure cutting current. used to minimize leakage at the puncture site. Despite its po- During this procedure, it is important not to separate the tip of the tential advantages, EUS-GBA has not been widely performed, echoendoscope from the gastric/duodenal wall because otherwise because acute cholecystitis with thick content requires contin- access may be accidentally lost. Next, a 5F nasobiliary drainage tube uous drainage. However, if placement of a drainage tube is not (ENBD-5; Cook Endoscopy) and/or covered self-expandable metal possible, single and repetitive EUS-GBA can be considered as stent (CSEMS; BONA-AL stent; Standard Sci Tech Inc., Seoul, Korea; alternative treatment modalities for patients with acute, high- 10 mm in diameter and 4–7 cm in length) is placed over the risk cholecystitis who cannot undergo emergency cholecys- guidewire. If there are thick pus and small particles of lithiasis, it tectomy. However, a further prospective study is warranted to may be necessary to place an additional nasobiliary catheter confirm this idea. through the stent lumen for continuous irrigation. The size of the stent is decided by approximating the distance between the gall- Technical considerations of EUS-GBD bladder and the gut wall with extra length based on EUS. Antibi- otics are permitted prior to the procedures. Although standardized techniques and devices for EUS-GBD EUS-guided transmural nasogallbladder drainage have not yet been established, there are several technical tips to remember for a successful procedure. First, the position of the In cholecystitis with thick content, placing a nasobiliary echoendoscope and selection of the puncture site are important. catheter into the gallbladder can be useful for repeat rinsing. From the anatomical point of view, it has been suggested that Generally, a 5F nasobiliary catheter for gallbladder drainage is punctures directed toward the neck of the gallbladder are pref- preferred, thus obviating the need for a large fistulous tract, erable, because this portion is fixed at the gallbladder bed in the which is the main risk factor for bile leakage.28 A nasogallbladder liver and connected to the extrahepatic bile duct by the cystic 24,27 25 drainage tube is less likely to be dislodged than a PTGBD tube.23 duct. Lee et al have suggested that punctures into the Follow-up cholecystography through the nasobiliary tube can be body of the gallbladder are effective when a nasobiliary drainage 24 performed to evaluate the patency of the cystic duct and tube is used. Song et al have reported that it may be reasonable whether there has been any leakage at the puncture site (Fig. 2). to use a transduodenal approach toward the neck of the gallbladder with a double-pigtail stent. If the body of the decom- EUS-guided transmural gallbladder stenting pressed gallbladder moves away from the gastric wall, stent migration may occur when a double-pigtail stent is used.24 When A7–8.5F double pigtail plastic stent or CSEMS is placed in the a catheter is accessed from the duodenal bulb, because of gallbladder. Metal stents have advantages over plastic stents when the angulation of the echoendoscope, the needle-knife points 32 Gastrointestinal Intervention 2013 2(1), 30–35

Fig. 1. Consecutive steps of endoscopic ultrasound (EUS)-guided transmural gallbladder drainage with a metal stent. (A) A 19-gauge needle was inserted into the gallbladder under EUS visualization. (B) Coiling of a 0.035 inch guidewire within the gallbladder under fluoroscopic guidance. (C) A modified covered self-expandable metal stent (CSEMS) was placed in position. (D) Endoscopic imaging revealed transgastric stent placement. tangentially and may result in an undesirable incision and Concerns about EUS-GBD postprocedural adverse events such as pneumoperitoneum or bleeding.32,33 Bile leakage The main postprocedural adverse event of EUS-GBD is bile leakage into the peritoneal space, which carries a significant The main risk related to EUS-GBD is bile leakage, because there risk of bile peritonitis.28 Complications such as bile leakage and is a gap between the gallbladder wall and the fistulous tract.28 pneumoperitoneum are associated with excessive fistula dila- However, a recent randomized controlled trial comparing the out- tion with a needle-knife, thus, it is important to use minimal di- comes of EUS-GBD and PTGBD has reported that there is no sig- lation with 6F dilator catheters or needle-knives as a rescue nificant difference in the safety of the procedure.23 It has also method.24,32,34,35 If the stent cannot be successfully placed into revealed that there is no bile leakage from the puncture site after the gallbladder after fistula dilation, bile peritonitis is more likely EUS-GBD.23 to occur after the procedure.28 Plastic stents have the drawback of a small lumen diameter, which can limit bile drainage and may increase the risk of stent migration.24,26 By comparison, EUS-GBD Is it less successful to drain thick or necrotic debris than PTGBD? with a CSEMS may reduce the risk of bile leakage, because the gap between the stent and the dilated fistulous tract can be imme- For PTGBD, an 8.5F pigtail drainage catheter is passed trans- diately sealed by the self-expanding metal stent.22 In addition, hepatically and placed in the intercostals space. A CSEMS with a the use of carbon dioxide for endoscopic insufflations instead 10-mm diameter has a larger diameter than the 8.5F pigtail of air is preferred during EUS-GBD, which helps to minimize the catheter, therefore, metal stents may facilitate drainage of the risk of pneumoperitoneum.36 Adequate gallbladder aspiration thick content of the inflamed gallbladder. If there are thick pus immediately after insertion of a nasobiliary drainage tube and and lithiasis, the physician can insert an additional nasobiliary frequent saline irrigation during admission could decrease the drainage catheter in the stent lumen for continuous monitoring risk of bile leakage.22,23 and irrigation.21 Jun-Ho Choi et al. / EUS-guided transmural gallbladder drainage 33

Fig. 2. Endoscopic ultrasound (EUS)-guided cholecystoenterostomy was performed in a 53-year-old female patient with a hilar cholangiocarcinoma. Because of prior biliary stent, transpapillary gallbladder drainage was unsuccessful. Distended gallbladder puncture was performed with a 19-gauge needle under EUS visualization. Thereafter, a 0.035 inch guidewire was coiled into the gallbladder. After ﬁstula dilation with a needle-knife, a covered, self-expandable metal stent was placed in position. A nasobiliary tube was addi- tionally placed through the stent lumen for continuous irrigation because of the thick content.

Is EUS-GBD more traumatic than PTGBD? early to draw a conclusion, we believe inserted stents will have no negative impact on the life expectancy of the patients. EUS-GBD can be used when there are massive ascites and when patients have coagulopathy or have been taking antithrombotic Review of published data on EUS-GBD agents. The procedure minimizes the risk of bleeding, because the puncture sites at the prepyloric antrum or duodenum are less In EUS-GBD, the technical and clinical success rate is 96.7– – vascularized than the liver as the primary puncture site for PTGBD. 100%.15,22 26 The overall rate of postprocedural adverse events is – 13.6%.15,22 26 Postprocedural adverse events include pneumo- – Relatively deeper sedation needed than PTGBD peritoneum, bile leakage, and stent migration.22 26 Recently reported comparisons between EUS-GBD and PTGBD among 59 Although patients experience less discomfort with EUS-GBD consecutive patients with acute cholecystitis who were unsuitable than with PTGBD, EUS-GBD needs relatively deeper sedation than for cholecystectomy showed no differences in relation to technical PTGBD.23 EUS-GBD requiring moderate to deep sedation could feasibility, efficacy, and safety.23 Conventional CSEMSs have a larger place a strain on patients of advanced age and those with under- lumen diameter but have a high risk of stent migration and bile lying comorbidity, compared with PTGBD, which requires only local leakage. Modified CSEMSs have been designed to obviate these anesthesia. Thus, EUS-GBD could be inappropriate in those cases. drawbacks by enlarging and bending the flared ends at a 90 angle (BONA-AL).22 In a previous study using CSEMSs, no patient en- When to remove the stent? countered bile leakage or bile peritonitis.22 Recently, Itoi et al have reported successful results with a newly developed lumen-apposing Based on our experience in transmural stenting of the gall- metal stent (AXIOS), a fully covered, 10-mm diameter, Nitinol bladder, we believe that in most cases, it is not necessary to remove braided stent with bilateral anchor flanges, placed in 20 patients.30 the stent.22,24,25 The development of a fistulous tract between the gallbladder and the stomach/duodenum is one of the natural ways Future prospects of EUS-GBD of drainage of the gallbladder. Even in the case of stent migration, the patient is likely to have no new episodes of cholecystitis due to The advantages of EUS-GBD are the avoidance of external the formation of a permanent mature fistula. Although it is too drainage (unlike PTGBD), and no potential risk of post-ERCP 34 Gastrointestinal Intervention 2013 2(1), 30–35

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