EUS- Gallbladder Drainage: is it time to replace percutaneous drainage?

EUS- Gallbladder Drainage: is it time to replace percutaneous drainage? Jessica Widmer, DO 1, Juveria Abdullah 1, Michel Kahaleh, MD. 1 Division of Gastroenterology and Hepatology, Department of Medicine, Weill Cornell Medical College, 1 New York, USA Running title: EUS guided gallbladder drainage Keywords: Endoscopic ultrasound, Therapeutic Endoscopy, EUS-guided drainage, EUS-guided intervention. Cholecystoduodenostomy Address for Correspondence: Michel Kahaleh, MD, AGAF, FACG, FASGE Professor of Medicine Chief of Endoscopy Division of Gastroenterology & Hepatology Department of Medicine Weill Cornell Medical College 1305 York Avenue, 4th Floor New York, NY 10021 Telephone: 646-962-4000 Fax: 646-962-0110 Email: mkahaleh@gmail.com

Abstract: Acute cholecystitis in patients who are not suitable for surgery can benefit from EUS- GBD to avoid percutaneous transhepatic gallbladder drainage (PT-GBD) associated with poor quality of life and increased morbidity. The technique involves EUS guided access of the gallbladder with creation of a gastric or duodenal fistula followed by placement of a stent. The overall reported technical success rate is 87/90 (96.6%). A total of 11/90 (12.2%) patients had complications including pneumoperitoneum, bile peritonitis and stent migration. EUS-GBD provide gallbladder drainage in situations where percutaneous or transpapillary drainage is not feasible or technically challenging, it also offer the patients a better option with improved quality of life and decreased global morbidity by avoiding percutaneous access.

Introduction: Surgical cholecystectomy has been the mainstay of treatment for acute cholecystitis. For patients with advanced age, comorbidities, use of anti-platelet medications, and/or the presence of advanced malignancy, gallbladder drainage has been recommended instead of surgery.[1] Techniques for non-surgical gallbladder drainage include percutaneous transhepatic gallbladder aspiration or drainage (PT-GBD) and transpapillary endoscopic gallbladder stenting.[2] Endoscopic transpapillary drainage can be technically difficult in some cases with biliary or pancreatic malignancy due to cystic duct obstruction or previously placed metal stents. The need for alternative methods of gallbladder drainage during the evolution of EUS guided drainage techniques for extraluminal collections such as pseudocysts has lead to development of EUS guided gallbladder drainage (EUS-GBD) techniques.[3-6]. Materials and methods: Echoendoscopes Conventional curved linear array oblique viewing therapeutic echoendoscopes are typically used (GF-UCT 180, Olympus America, Melville, NY). The working channel of this scope is 3.7 mm, allowing placement of 10 mm fully covered metal stents and 10 F double pigtail stents.[7] Itoi and colleagues have also reported the use of a prototype forward view curved linear array echoendoscope, which may enable the endoscopist to overcome this issue by exerting force directly with the scope towards the target.[8]

Patient selection and preparation Contrast enhanced abdominal CT or magnetic resonance imaging should be reviewed as a roadmap prior to endoscopic intervention. This procedure is frequently performed under general anesthesia, although conscious sedation is also used at the discretion of the endoscopist. Peri-procedural antibiotics are often administered. EUS guided gallbladder drainage technique (Table 1) Endoluminal puncture site Endoscopic ultrasound is used to identify the site of initial puncture at a location where the gallbladder lies closest to the bowel lumen, avoids blood vessels and a stable position of the endoscope tip can be easily maintained. The gastric antral wall has been the preferred site for the initial puncture to access in few large case series,[9-11] while some authors report the use of a transduodenal approach with similar success rates.[8, 12] Lee and colleagues reported use of the transgastric approach to access the body of the gallbladder and the transduodenal approach for the gallbladder neck.[13] In early reports of EUS-GBD, Lee et al. and Baron et al. commented that directing the puncture needle to the gallbladder neck can be advantageous since it is less mobile and is less likely to move away from the duodenal wall.[13, 14] Puncture needle

Most reports have consistently used a 19 gauge fine needle aspiration (FNA) needle to obtain access (Figure 1). Subtil et al. have described use of a one step device (Giovannini Needle Wire Oasis, Cook Ireland Ltd, Limerick, Ireland), which allows puncture, dilation, electrocautery, and placement of the stent in one device.[11] This system is advantageous because it reduces the time that passes from the initial needle puncture until stent deployment, which reduces the risk of loss of guidewire access and potential complications. However, this system is only available for 8.5 and 10 F straight stents.[11] Tract dilator After gaining access with a 0.035 inch guidewire, which is coiled into the gallbladder, the fistula tract is dilated using either a mechanical or electrocautery device (Figure 2). A biliary dilation catheter (Soehendra, Cook Medical) has been used as the initial dilating device in many reports.[10, 13, 15-17] A triple lumen cystoenterostome (6F or 10F Cysto-Gastro Set, Endo-flex, Voerde, Germany or Cystotome, Cook Endoscopy) is another preferred dilation device, which can assist in dilation using diathermy and/or a needle knife.[15] [8-12, 16] A cystoenterostome has the advantage of performing dilation without lifting the ultrasound probe from the gut wall while diathermy causes melting of tissue and inflammatory reaction which can aid in keeping the tissue layers together. [12] Some authors have described the use of 4 mm hurricane biliary balloon dilator either alone or in tandem with the methods mentioned above to achieve adequate dilation.[8, 9]

Endoprosthesis After tract dilation, the stent delivery system or stent followed by the pushing catheter is advanced over the wire and into the cyst. The tip of echoendoscope is then carefully lifted from the luminal wall maintaining the direction to allow visualization of the stent deployment. The distal end of stent is deployed under fluoroscopic guidance, then the proximal end is then deployed endoscopically. The stent length is determined by the combined thickness of the interposed tissue as measured by EUS (Figure 3). Plastic biliary stents (PBS) were used in most early studies describing EUS-GBD. A variety of PBS such as double pigtail, single pigtail and straight have been used with similar success rates (Table 1). [11-13, 16-18] The insertion of a plastic stent usually requires a tract diameter slightly larger than the stent to be placed, which could lead to a gap and potential leakage. [10] Self expanding metal stents (SEMS) were used for EUS-GBD in one case series of fifteen patients in an attempt to circumvent the limitations of PBS by sealing the gap between the stent and the fistula as the stent expands. [10] SEMS can also be repositioned if desired, avoiding the need for a second puncture. Jang and colleagues described the use of 10 mm diameter covered metal stents (BONA-AL Standard Sci Tech Inc, Seoul, Korea), which are modified with flared ends up to 22 mm to prevent migration. [10] The larger diameter of the stent lumen also decreases risk of stent occlusion. Lumen-apposing stents (AXIOS, Xlumena Inc, Mountain View, California) are the newest development in the arena of EUS-GBD. The AXIOS stents have a 10 mm diameter with bilateral anchor flanges, which provide lumen to lumen apposition and prevent leakage. [8] It is also possible to access the

gallbladder lumen through the stent with a slim endoscope to perform biopsies, remove stones or for debridement.[8, 9, 19] Literature Review (Table 1) Indications for the procedures included patients with acute cholecystitis that were not suitable for surgical cholecystectomy due to malignancy or other comorbidities and/or after failed endoscopic transpapillary gallbladder stenting. The initial needle puncture was made in a transgastric fashion in 54/73 patients (74%) and transduodenally in 19/73 patients (26%). One study including 30 patients did not specify whether the puncture was performed transgastrically or transduodenally. Nasocystic drainage tubes were used in 41/103 (39.8%) patients, plastic stents were used in 16/103 (15.5%) of patients, and covered metal stents were used in 46/103 (44.6%) patients. The overall reported technical success rate is 100/103 (97.1%). Technical failures were attributed to loss of guidewire access (n = 1), uncontrolled stent release (n = 1) and cobblestone gallbladder limiting advancement of guidewire (n = 1). Clinical success defined as improvement in clinical and laboratory parameters was achieved in 100% patients when EUS-GBD was technically successful. A total of 11/103 (10.7%) patients had complications. Pneumoperitoneum (n = 6) was the most commonly reported complication and was self-limited in all cases. [10, 13, 15, 16] Bile peritonitis (n = 1) and stent migration (n = 1) were reported with placement of PBS.[16] Bile peritonitis was managed conservatively. Distal stent migration was seen as a late complication at 3 weeks post-procedure and was without clinical consequence. [16] AXIOS stents have been associated with self-limited hematochezia (n = 1), right

hypochondrium pain (n = 1) and oozing at fistula site (n = 1). [8, 9] Other procedure related events reported include: transient dislodgement of cystoenterostome requiring a second puncture with a resultant small bile leak, and clogging, migration or spontaneous expulsion of stent without clinical consequences. [9, 11, 12, 15, 16] Discussion: Percutaneous techniques have been used for gallbladder drainage for years with good technical and clinical success rates. Risks involved with PT-GBD include liver injury secondary to puncture causing hemorrhage, pneumothorax, bile leak, dislodged tube, and skin site infections, which compromise quality of life and increase length of hospital stay. [2] PT-GBD has a complication rate ranging up to 12%[20] and issues such as catheter related pain, management of bile bag and cosmetic problems affect quality of life. [21] Most patients treated with percutaneous techniques eventually will need a cholecystectomy or acute cholecystitis can recur.[22] To overcome these limitations, there has been a need for find alternative techniques to manage patients with acute cholecystitis who are poor surgical candidates. ET-GBD can be technically challenging in the setting of acute cholecystitis and has a risk of post-ercp pancreatitis.[23, 24] It may not be feasible in patients with an inaccessible papilla or biliary obstruction due to malignancy. EUS-GBD can be a valuable alternative in selected patients not candidates of PT-GBD or ET-GBD. EUS- GBD is carried out through gastric or duodenal wall, avoiding puncture of liver, which is more vascular and is safer in patients with coagulopathy or using anti-platelet agents.

[7-13, 15-18] It can also be performed safely in patients with perihepatic ascites where PT-GBD is not feasible. The technique of EUS guided drainage has evolved over past decade with drainage of extraluminal collections such as pancreatic pseudocysts, necrosis and abscesses. [25, 26] We have previously reported drainage of bilomas and gallbladder fossa fluid collections with success. [6, 27] Baron and colleagues first reported successful EUS guided transduodenal gallbladder drainage using double pigtail PBS in a patient with cholangiocarcinoma and bilateral metal biliary stents. [14] Limited apposition of PBS with the tract wall lead to bile leak and stent migration[11, 16], although it has been postulated that thickened gallbladder wall and or surrounding adhesions can decrease the risk of bile leak. [13, 14] Most authors have used 7 F or 8.5 F diameter PBS which could clog due to thick drainage. [16] SEMS avoid these potential limitations of PBS by causing apposition at the tract wall to decrease chances of leakage and a have wider internal diameter that reduces the risk of clogging. Jang and colleagues described use of partially covered SEMS modified by adding flaring and angulations at the distal ends to prevent stent migration.[10] The ends of SEMS have the potential to cause injury and bleeding by abutting with the gallbladder or bowel lumen, although this has not been reported.[28] The lumen apposing AXIOS stent is another modification of SEMS by means of a saddle shape with distal anchor flanges to ensure both lumen apposition and drainage. Three recent case series involving 31 patients have shown reasonable success rates.[8, 9, 19] Deployment of AXIOS stents can be technically challenging, particularly in patients with a thickened gallbladder wall leading to low technical success rates in the initial pilot study. [9] These stents have been shown to provide an additional

advantage of allowing access to the gallbladder lumen with slim (<10 mm) endoscope to perform biopsies, stone removal or debridement. [8, 9, 19] Early experience with EUS-GBD procedures has shown minimal adverse events. Pneumoperitoneum, the most common adverse event, was reported only in case series using a biliary dilation catheter for tract dilation. Due to lack of detailed information on individual cases, pneumoperitoneum cannot be clearly be attributed to biliary dilation catheters, but it has been postulated that the sheer force by the dilators has potential to detach and push away the gallbladder wall possibly leading to pneumoperitoneum. SEMS or lumen-apposing AXIOS stents are promising since complications associated with PBS such as bile leak and stent migration have not been reported. EUS-GBD with placement of SEMS or AXIOS stent is a reasonable palliative option in patients with malignancy affecting biliary system and avoids recurrence of cholecystitis due to stent blockage or removal as seen with other techniques which use smaller diameter drains. EUS-GBD with AXIOS can also aid in treatment of large stones by performing cholecystoscopy. [9] In summary, EUS-GBD is an evolving alternative to PT-GBD or ET-GBD in selected patients as a bridge to surgery or for palliation. The potential to perform therapeutic maneuvers will expand its applications in future. With continued development of EUS drainage accessories and experience with the drainage techniques, EUS-GBD is likely to have better technical success rates with minimal adverse events. With the widespread adoption of EUS-GBD, the indications are likely to expand. It can potentially be an access point for therapies directed towards biliary tree or liver such as photodynamic therapy, radiofrequency ablation through a transcystic approach in

patients with inaccessible ampulla due to malignancy or altered anatomy after bariatric surgery.

Table Legend Table 1: Summary of studies describing endoscopic ultrasound guided gallbladder drainage

Table 1: Summary of studies describing endoscopic ultrasound guided gallbladder drainage Author/Year/lo cation Moon et al. [19] 2014 Korea Jang et al.[15] 2012 Korea Itoi et al.[8] 2012 Japan Num ber of cases Indications 13 Acute cholecystitis, gallbladder cancer, pancreatic fluid collections 30 Acute cholecystitis unsuitable for emergency cholecystectom y 5 Aute cholecystitis in non-surgical candidates (3 pancreatic cancers, 1 cholangiocarci noma 1 gallstone Initial puncture site Tract dilatior Stomach 6-8F dilating catheter Needle knife 4 mm balloon catheter Stomach or duodenal wall (numbers not specified) 1 stomach 4 duodenum 6F dilator catheter (43.3%) Triple lumen needle knife (56.7%) 4 mm hurrican e dilating balloon (N=4) 10F cystoto Endoprost hesis for drainage Lumen apposing stent (AXIOS, Xlumena Inc, Mountain View, CA) 10 mm diameter 5 F nasobiliary drainage tube Lumen apposing stent (AXIOS, Xlumena Inc, Mountain View, CA) 10 mm Mean proced ure time (min) Not reporte d Techni cal success rate Clini cal succe ss rate Length of follow up Limitatio ns Complicat ions 100% 100% 6 months None None 23 ± 7 97% 100% 221 days (6 days for patients who underwent cholecystect omy) Loss of guide wire access Pneumoperito neum (2/30) Self limiting 23.4 100% 100% 9 months None Mild self limited oozing along fistula tract

Serna-Higuera et al.[9] 2012 Spain Jang et al. [10] 2011 Korea Song et al. [16] 2010 Korea disease) 13 Acute cholecystitis in non surgical candidates for emergent cholecystectom y 15 Acute Cholecystitis unsuitable for cholecystectom y after failed ERCP with transpapillary cystic approach 8 Acute Cholecystitis poor surgical candidates after failed 12/13 transgastri c-antral 1/13 transduode nal 10/15 transgastri c- prepyloric antrum 5/15 transduode nal 7/8 transduode nal 1/8 transgastri me (N=1) 8.5F Cystoto me followed by 4mm hurrican e biliary balloon dilator -6 or 7 F Soehend ra biliary dilation catheter -Triple lumen needle knife microto me -6 or 7 F tapered tip biliary dilation diameter (length 6mm in 4 cases and 10 mm in one case) -Lumen apposing stent (AXIOS, Xlumena Inc, Mountain View, CA) -Additional fully covered SEMS within AXIOS in 4 subjects Partially covered SEMS 10 mm diameter and 4-7 mm length (Modified* BONA-AL Stent, Standard Sci Tech Inc, Seoul, Korea) 7F doublepigtail plastic stent Not reporte d Not reporte d 28 (range 17-32) 84.6% 100% 100.81 days Thickene d gallbladd er wall Uncontrol led stent release Hematochezia (1/11) Right hypochondrium pain (1/11) Both self limiting 100% 100% 145 days None Pneumoperito neum (2/15) Self limiting 100% 100% 186 days Clogging of stent (no clinical conseque 1 pneumoperitoneum (self limiting) 1 bile peritonitis

Subtil et al. [11] 2010 Spain Kamata et al. [17] 2009 Japan Takasawa et al.[18] 2009 Japan transpapillary cystic approach (4 cholangiocarci noma, 2 liver cirrhosis, 1 on anticoagulation, 1 malignant cystic duct obstruction) 4 Acute cholecystitis with perforation and perigallbladder abscess in non surgical candidates (1 Alzheimer s, 3 advanced hepatobiliary malignancies) 1 Acute cholecystitis in patient with malignant biliary obstruction treated with covered SEMS 1 Acute cholecystitis in patient with malignant biliary obstruction after SEMS c Transgastr icprepyloric antrum Transgastr ic Transgastr ic catheter -7F Triple lumen needle knife microto me (6/8) -10F cystoto me (1 case) -Onestep system NWOA (Giovan nini Needle Wire Oasis (3 cases) Serial 6 Fr, 7 Fr, and 9 Fr; Soehend ra biliary dilation catheters Needle knife papiloto me 8.5F stent modified Cotton- Leung (Amsterda m) 10F stent modified Soehendra Tannenbau m Biliary 7F X 4 cm double pigtail 7.2 Fr, 30 cm-long, single pigtail plastic tube Not reporte d Not reporte d Not reporte d nce) 100% 100% Not reported Stent migration into gall bladder Spontane ous stent expulsion 1 distal stent migration None 100% 100% 6 months None None 100% 100% 10 days None None

Kwan et al. [12] 2007 Belgium Lee et al.[13] 2007 Korea Baron et al.[14] 2007 USA 3 Acute Cholecystitis in non surgical candidates 9 Acute Cholecystitis (Gallstone induced) in elderly or high risk due to co morbidities or on anticoagulation not suitable emergent cholecystectom y 1 Acute Cholecystitis in patient with cholangiocarci noma with bilateral metal biliary stents 1 Transgastr ic-antral 2 transduode nal 4 transgastri c 5 transduode nal Transduod enal 6F or 10F Cysto- Gastro Set [Endoflex, Voerde, German y] Cystoto me [Cook endosco py] 6F or 7F bougie (Soehen dra biliary dilatatio n catheter) 4 mm balloon Single pigtail nasocholec ystic drain together or followed by 8.5F Doublepigtail stent (Zimmon biliary stent) 5F nasobiliary drainage tube 7F X 4cm double pigtail biliary stent Not reporte d 20 (range 10-35) Not reporte d 100% 100% 6 weeks Transient dislodge ment of cystoenterosto me causing small bile leak and requiring repeat puncture None 100% 100% 3-12 months None Pneumoperito neum (1/9) self limiting 100% 100% 11 weeks None None

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13. Lee, S.S., et al., EUS-guided transmural cholecystostomy as rescue management for acute cholecystitis in elderly or high-risk patients: a prospective feasibility study. Gastrointest Endosc, 2007. 66(5): p. 1008-12. 14. Baron, T.H. and M.D. Topazian, Endoscopic transduodenal drainage of the gallbladder: implications for endoluminal treatment of gallbladder disease. Gastrointest Endosc, 2007. 65(4): p. 735-7. 15. Jang, J.W., et al., Endoscopic ultrasound-guided transmural and percutaneous transhepatic gallbladder drainage are comparable for acute cholecystitis. Gastroenterology, 2012. 142(4): p. 805-11. 16. Song, T.J., et al., EUS-guided cholecystoenterostomy with single-step placement of a 7F double-pigtail plastic stent in patients who are unsuitable for cholecystectomy: a pilot study (with video). Gastrointest Endosc, 2010. 71(3): p. 634-40. 17. Kamata, K., et al., Transgastric endoscopic ultrasound (EUS)-guided gallbladder drainage for acute cholecystitis. Endoscopy, 2009. 41 Suppl 2: p. E315-6. 18. Takasawa, O., et al., Endosonography-guided gallbladder drainage for acute cholecystitis following covered metal stent deployment. Dig Endosc, 2009. 21(1): p. 43-7. 19. Moon, J.H., et al., A newly designed fully covered metal stent for lumen apposition in EUS-guided drainage and access: a feasibility study (with videos). Gastrointest Endosc, 2014. 79(6): p. 990-5. 20. McGahan, J.P. and K.K. Lindfors, Percutaneous cholecystostomy: an alternative to surgical cholecystostomy for acute cholecystitis? Radiology, 1989. 173(2): p. 481-5. 21. Spira, R.M., et al., Percutaneous transhepatic cholecystostomy and delayed laparoscopic cholecystectomy in critically ill patients with acute calculus cholecystitis. Am J Surg, 2002. 183(1): p. 62-6. 22. Bakkaloglu, H., et al., Ultrasound guided percutaneous cholecystostomy in high-risk patients for surgical intervention. World journal of gastroenterology : WJG, 2006. 12(44): p. 7179-82. 23. Feretis, C., et al., Endoscopic drainage of acute obstructive cholecystitis in patients with increased operative risk. Endoscopy, 1993. 25(6): p. 392-5. 24. Pannala, R., et al., Endoscopic transpapillary gallbladder drainage: 10-year single center experience. Minerva Gastroenterol Dietol, 2008. 54(2): p. 107-13. 25. Prasad, G.A. and S. Varadarajulu, Endoscopic ultrasound-guided abscess drainage. Gastrointest Endosc Clin N Am, 2012. 22(2): p. 281-90, ix. 26. Seewald, S., et al., EUS-guided drainage of pancreatic pseudocysts, abscesses and infected necrosis. Dig Endosc, 2009. 21 Suppl 1: p. S61-5. 27. Kahaleh, M., et al., Drainage of gallbladder fossa fluid collections with endoprosthesis placement under endoscopic ultrasound guidance: a preliminary report of two cases. Endoscopy, 2005. 37(4): p. 393-6. 28. Talreja, J.P., et al., Transenteric drainage of pancreatic-fluid collections with fully covered self-expanding metallic stents (with video). Gastrointest Endosc, 2008. 68(6): p. 1199-203.

FIGURE LEGENDS 1-Figure 1: EUS guided puncture of the gallbladder 2-Figure 2: Fluoroscopy images of balloon dilation 3-Figure 3: Endoscopic images of deployed lumen apposing metal stent between the gallbladder and the bulb