J Hepatobiliary Pancreat Sci (2019) 26:249–269
DOI: 10.1002/jhbp.631

GUIDELINE

Clinical practice guidelines for safe performance of endoscopic
ultrasound/ultrasonography-guided biliary drainage: 2018
Hiroyuki Isayama  Yousuke Nakai  Takao Itoi  Ichiro Yasuda  Hiroshi Kawakami  Shomei Ryozawa 
Masayuki Kitano  Atsushi Irisawa  Akio Katanuma  Kazuo Hara  Takuji Iwashita  Naotaka Fujita  Kenji
Yamao  Masahiro Yoshida  Kazuo Inui
Published online: 28 June 2019

© 2019 The Authors. Journal of Hepato-Biliary-Pancreatic Sciences published by John Wiley & Sons Australia, Ltd on behalf of JapaneseSociety of Hepato-Biliary-Pancreatic Surgery.

The author’s afﬁliations are listed
in Appendix 1.
Correspondence to: Hiroyuki
Isayama, Department of
Gastroenterology, Graduate Schoolof Medicine, Juntendo University,
2-1-1 Hongo, Bunkyo-ku, Tokyo
113-8421, Japan.
e-mail: h-isayama@juntendo.ac.jp
This is an open access article under
the terms of the Creative Commons
Attribution License, which permitsuse, distribution and reproduction
in any medium, provided theoriginal work is properly cited.
DOI: 10.1002/jhbp.631

Abstract Endoscopic ultrasound/ultrasonography-guided biliary drainage (EUS-BD) isa relatively new modality for biliary drainage after failed or difﬁcult transpapillary biliary
cannulation. Despite its clinical utility, EUS-BD can be complicated by severe adverse
events such as bleeding, perforation, and peritonitis. The aim of this paper is to provide
practice guidelines for safe performance of EUS-BD as well as safe introduction of theprocedure to non-expert centers. The guidelines comprised patient–intervention–comparison–outcome-formatted clinical questions (CQs) and questions (Qs), which arebackground statements to facilitate understanding of the CQs. A literature search was
performed using the PubMed and Cochrane Library databases. Statement, evidence level,and strength of recommendation were created according to the GRADE system. Four
committees were organized: guideline creation, expert panelist, evaluation, and external
evaluation committees. We developed 13 CQs (methods, device selection, supportive
treatment, management of adverse events, education and ethics) and six Qs (deﬁnition,
indication, outcomes and adverse events) with statements, evidence levels, and strengthsof recommendation. The guidelines explain the technical aspects, management of adverse
events, and ethics of EUS-BD and its introduction to non-expert institutions.
Keywords Biliary stricture Endoscopic ultrasonography EUS-guided biliary
drainage Interventional EUSIntroduction
Endoscopic biliary drainage for obstructive jaundice and acute cholangitis includes biliary stenting and endoscopic nasobiliary drainage by endoscopic retrograde cholangiopancreatography (ERCP). However, these techniques cannot be applied in somepatients with difﬁcult or impossible biliary cannulation, gastric outlet obstruction, or asurgically altered anatomy. Since Wiersema et al. [1] ﬁrst reported endoscopic ultrasound (EUS)-guided cholangiopancreatography in 1996, several modiﬁcations of EUSguided biliary drainage (EUS-BD), such as EUS-guided bilioduodenal anastomosis [2],which creates a ﬁstula between the common bile duct and duodenum, have been made,and the use of this technique in clinical practice is increasing rapidly. However, thetechniques and devices require further improvement for safe and widespread use of
EUS-BD, for which the current guidelines provide critical information.
The purpose of these guidelines is to provide information on the safety of EUS-BD
and on the methods for its introduction to more institutions, with the aim of improving
clinical practice and promoting safe performance of the technique. The steering

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committee expects that the guidelines will promote widespread and safe performance of EUS-BD in a large number of institutions. These guidelines are targeted topatients and their families, physicians, and other medical
staff, to provide information on the current status of EUSBD. The guidelines also aim to improve the outcomes of
EUS-BD for biliary tract diseases, focusing on biliary
obstruction, including obstructive jaundice and acutecholangitis. Since EUS-BD is still in the introduction
phase and high-quality evidence is lacking, our guidelines
need to be updated as novel dedicated devices are developed and more evidence is accumulated in the future.

J Hepatobiliary Pancreat Sci (2019) 26:249–269

CQs and six Qs were generated by the guideline committee,
and one member was assigned to each question.
Evidence collection
The committee member responsible for each CQ performed a systematic literature search in PubMed and the
Cochrane Library and produced a reference list based on
the content and design of each identiﬁed study. The literature search was limited to the period from January 1990
to May 2018.
Method of evidence assessment and systematic review

Methods
Committee organization and approval process ofconsensus among committee members
A guideline creation committee, expert panelist committee,
evaluation committee, and external evaluation committee wereorganized (Appendix 2). Because the guidelines focus on thetechnical aspects of EUS-BD, members of the guideline creation and expert panelist committees were selected fromamong gastroenterologists with expertise in endoscopy andinterventional radiology (IVR). Two external evaluation committee members who are experts in the guideline creation process were invited to evaluate the guidelines and provide
recommendations for their improvement. The ﬁrst step in creating the guidelines was to identify clinically important issues
and generate patient–intervention–comparison–outcome-formatted clinical questions (CQs) and evaluate the evidence in asystematic review. The next step was to evaluate the clinicalevidence, risk–beneﬁt balance, wishes of the patients, andmedical costs. The third step was to generate the statements.
However, few studies on EUS-BD have provided high-quality
evidence. Therefore, the statements, recommendation levels,and evidence levels were determined based on the GRADE
system, which is described in detail later, and were decided by
an expert consensus survey. Voting was performed via theinternet to avoid the inﬂuence of other committee members’
opinions. The statements in each CQ were assigned a score of
9 or lower, and the voting was repeated until the mean scorereached ≥7.

Process of guideline creation
Creation of CQs and Qs
Draft patient–intervention–comparison–outcome-formatted
CQs for important clinical subjects and Qs for backgroundinformation to understand the CQs were generated. Thirteen

The evidence was summarized based on the systematic
review of the literature related to EUS-BD. The evidence
levels and recommendation levels determined using the
GRADE system are listed in Tables 1 and 2.
Decision of statements and creation of draft guidelines
First, a draft statement of each CQ and Q was createdbased on the risk–beneﬁt balance, wishes of the patients,and medical costs; the evidence level was appended as anote (ﬁrst draft). After discussion among the guideline
creation committee members, revised statements (second
draft) were preliminarily voted on by the expert committee via the internet as a consensus survey. Agreement of
the statements was deﬁned as a mean score for all CQs of≥7, and expository text was created for each CQ. Next,
three face-to-face meetings were held to revise each statement and its commentary text (third draft). The expert
panelist committee voted via the internet, and the third
draft statements and commentary text approved by consensus were added. The third draft was further revised
according to the opinions of the expert panelist committee; in this way, the draft statements, evidence levels, andcommentary text were created.
Creation of the ﬁnal draft and the ﬁnalization process
The draft guidelines were proposed to the public on 29
September 2018 at the 52nd Japan Biliary Association
Annual Scientiﬁc Meeting. The draft was revised basedon the collected comments and opinions, and the revised
draft was further reviewed and revised by the evaluationcommittee. The ﬁnal draft was posted on the website of
the Japan Biliary Association from 24 August to 30
September 2017. The public comments received wereincorporated into the ﬁnal draft, which was further revised
and/or corrected and modiﬁed with the approval of theguideline creation committee. The guidelines were

J Hepatobiliary Pancreat Sci (2019) 26:249–269

251

Table 1 Methods of decision of evidence levels according to the Grade system
Initial quality of evidence

Study design

Lower if

Higher if

High
Moderate
Low
Very low

RCT, systematic review, meta-analysis
Observational study (cohort study, case control study)
Any other evidence (case series, case study)

Study limitations:
1 Serious
2 Very serious
Inconsistency:
1 Serious
2 Very serious
Indirectness:
1 Serious
2 Very serious
Impression:
1 Serious
2 Very serious
Publication bias:
1 Likely
2 Very likely

Magnitude of effect:
2 Very strong
1 Strong
Dose-response gradient 1
All plausible confounders
would have reduced the effect 1

Level A high, Level B moderate, Level C low, Level D very low
Overall quality of evidence across studies for the outcome

Table 2 GRADE system (grade of recommendation)
1. How to judge a Grade of recommendation
Total judgment with evidence, harm and beneﬁt
Level of evidence
A, B, C, D
Patient’s preference
Yes, No
Harm and beneﬁtYes, No
Cost effectiveness
Yes, No
2. How to show a Grade of recommendation: 2 steps
Recommendation 1: Strong recommendation (do it, don’t do it)
Recommendation 2: Weak recommendation (probably do it,probably don’t do it)

ﬁnalized according to the evaluation by and advice of themembers of the external evaluation committee.

The GRADE system
In the guidelines, the evidence grade was deﬁned according
to the GRADE system, as follows: A, high (strong evidence);
B, moderate (moderate evidence); C, low (low evidence);
and D, very low (weak evidence). The recommendation
grades are 1 (strong recommendation) and 2 (weak recommendation). Table 1 lists the quality-of-evidence and gradelevels of the GRADE system [3–5], and Table 2 shows the
GRADE system recommendations [3–5].

Questions and clinical questions of the guidelines
Q1. What is endoscopic ultrasound-guided biliary
drainage (EUS-BD)?

EUS-BD is deﬁned as transmural biliary accessunder endoscopic ultrasound guidance with subsequent biliary drainage.
Mean voting score (range): 7.7 (1–9)

EUS-BD for obstructive jaundice is an endoscopic transmural biliary drainage approach to the biliary tract under
EUS guidance. An ERCP approach is widely used for the
diagnosis and treatment of pancreatobiliary diseases. For
obstructive jaundice, transpapillary endoscopic biliary
drainage (EBD) is the ﬁrst choice. For patients in whom
EBD is difﬁcult, percutaneous transhepatic biliary drainage (PTBD) or hepaticojejunostomy is performed. However, these procedures are highly invasive, have risks ofcomplications, and affect the quality of life of the patient.
Thus, EUS-BD was developed as an alternative drainage
modality.
EUS-BD is either a transmural biliary drainage
that creates a ﬁstula between the gastrointestinal tract
and the biliary tract (including EUS-guided choledochoduodenostomy [CDS, Fig. 1] and EUS-guided hepaticogastrostomy [HGS, Fig. 2]) or a transpapillary or
antegrade approach after EUS-guided puncture of thebile duct (including EUS-guided rendezvous [EUS-RV]
and EUS-guided antegrade stenting [EUS-AGS]). The
procedure is selected according to the patient’s background, treatment indications, and difﬁculty of endoscopic retrograde cholangiography (ERC). EUS-guided
gallbladder drainage can be used if bile duct puncture
is difﬁcult, and biliary drainage is performed via thegallbladder. This procedure is also carried out for acutecholecystitis.

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(a)

J Hepatobiliary Pancreat Sci (2019) 26:249–269(b)Fig. 1 EUS-guided choledochoduodenostomy (EUS-CDS). (a) Puncture of thecommon bile duct under EUS-guidance.
(b) Fluoroscopy after EUS-CDS stentplacement. (c) Endoscopic view after
EUS-CDS stent placement(c)

Wiersema et al. [1] ﬁrst reported EUS-guided cholangiography in 1996. In that study, a 22- or 23-gauge (G)needle for ﬁne-needle aspiration (FNA) was used forcholangiography in 10 cases and for pancreatography in
one case; the procedure was successful in eight cases. In
2001, Giovaninni et al. [2] reported on EUS-guided bilioduodenal anastomosis, namely EUS-CDS, in which a ﬁstula was created between the common bile duct and theduodenum for biliary drainage. In 2003, Burmester et al.
[6] reported four cases with EUS-guided cholangio-drainage and one with intrahepatic bile duct puncture, namely
EUS-HGS, via the transgastric approach. Since the terms“EUS-CDS” and “EUS-HGS” are widely used globally,
the current guidelines also used these terms. However, in
EUS-CDS, the bile duct was punctured not only at “choledocus (the common bile duct)” but also the common hepatic duct, and the term “EUS-CDS” does not always
represent the accurate anatomy. Although there are some
opinions that the term should be either “intrahepatic” or“extrahepatic” to accurately describe the puncture site,
there is no consensus on this and the terms EUS-CDS andHGS are widely used in clinical practice.
In addition to transmural biliary drainage, Mallery
et al. [7] in 2004 reported on biliary drainage using EUSRV, in which needle puncture into the bile duct is performed under EUS guidance followed by selective biliary
cannulation using a guidewire advanced into the duodenum. Fujita et al. [8] reported a two-stage stent placement
procedure in which a guidewire was inserted into the bile
duct through a temporary ﬁstula created by EUS-HGS to
the duodenum in an antegrade manner, followed by placement of a metal stent in the bile duct, similar to EUSAGS. In 2010, Nguyen-Tang et al. [9] reported ﬁve casesof EUS-guided antegrade stent placement. In addition to
the procedures described above, EUS-guided hepaticojejunostomy [6] from the jejunum to the intrahepatic bile
duct in cases with surgically altered anatomy and EUShepaticoduodenostomy [10] from the duodenum to theintrahepatic bile duct have also been reported.

Q2. What are the indications for EUS-BD?

EUS-BD is used in patients with failed or difﬁcult
ERC who require biliary drainage.
Mean voting score (range): 8.3 (7–9)
EUS-BD can be applied in patients with failed or difﬁcult
ERC, and unresectable malignant biliary obstruction canbe a good indication [11–18]. The causes of failed or difﬁcult ERC include failed biliary drainage for various
anatomical reasons, difﬁcult endoscope advancement due
to duodenal stenosis by tumor invasion, an indwelling duodenal stent for gastric outlet obstruction, or a surgicallyaltered anatomy. The success rate of EBD is 84.0–95.6%[19, 20], and additional procedures, including precut
sphincterotomy, can increase the success rate of biliary
cannulation to 80.2–100% [21]. The rate of patients withfailed or difﬁcult ERC who required EUS-BD is reportedly
0.6% (3/524 cases) at high-volume tertiary-care centers[22]. Thus, few patients require EUS-BD as a salvage procedure.
Although EUS-BD has been used as the ﬁrst-line drainage method [23, 24], consensus on its use in cases in

J Hepatobiliary Pancreat Sci (2019) 26:249–269
Fig. 2 EUS-guided hepaticogastrostomy(EUS-HGS). (a) Fluoroscopy of EUSguided puncture of the left intrahepatic
bile duct. (b) Endoscopic view after
EUS-HGS. (c) Fluoroscopy after EUSHGS. (d) CT image of the EUS-HGS
stent

253
(a)

(b)

(c)

(d)

which ERC can be performed has not been established.
Kawakubo et al. [25] retrospectively compared the clinicaleffectiveness and complication rates of EUS-CDS (n = 26)
and EBD (n = 56) in patients with unresectable malignant
distal biliary obstruction. While the clinical effectiveness(96.2% vs. 98.2%; P = 0.54) and complication (26.9% vs.
35.7%; P = 0.46) rates were comparable, EUS-CDS had ashorter procedure time (19.7 vs. 30.2 min; P < 0.01), andnone of the patients developed pancreatitis. Hamada et al.
[26] compared EUS-BD (n = 7) and EBD (n = 13) inpatients with duodenal stent placement. The stent failureand complication rates were similar, but the stent-patency
rates at 1 month (100% vs. 71%) and 3 months (83% vs.
29%) were higher for EUS-BD. More recently, three randomized controlled trials [27–29] comparing EUS-BD and
ERCP-biliary drainage were published (Table 3). Although
all studies demonstrated comparable clinical outcomes, thestudies were underpowered by a small sample size and alarge scale prospective study is warranted.
EUS-BD can be the optimal treatment modality forpatients in which EBD is difﬁcult to perform due to a surgically altered anatomy. Siripun et al. [30] performed asystematic review of EUS-BD and found that the success,clinical effectiveness, and complication rates were 89.2%,
91.7%, and 17.5%, respectively, similar to those of EUSBD. In an international, retrospective study comparing
EUS-BD and enteroscopy-assisted ERCP in 98 surgicallyaltered anatomy cases [31], EUS-BD was associated withhigh technical success rate (odds ratio [OR] 12.48, P =0.001) but the adverse event rate was higher in EUS-BD(20% vs. 4%; P = 0.01). However, technical success ratesof EUS-BD and enteroscopy-assisted ERCP might differ
by local expertise and a further prospective study is warranted. However, there are no prospective studies comparing EUS-BD and enteroscopy-assisted ERCP; therefore,
further studies are necessary.
Ogura et al. [32] reported successful re-intervention
using EUS-BD in patients with malignant hilar biliary
obstruction and stent failure; the success rate of re-intervention by ERC was 62% (16/26), and EUS-BD was successful in all 10 cases of ERC failure. These cases may
have relative indication for EUS-BD because the procedure
has not yet been established, and such patients frequently
have a complex pathology. Thus, EUS-BD should be performed by experts only.
There are few studies of EUS-BD for resectable malignant biliary obstruction; therefore, the evidence level islow. Fujita et al. [33] performed EUS-CDS followed bysurgical resection and pathological examination; none ofthe patients displayed severe inﬂammation or bile leakage.
However, performing EUS-BD in resectable cases is notrecommended.
The indications for EUS-BD for benign biliary stricture
include a surgically altered anatomy (for which

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J Hepatobiliary Pancreat Sci (2019) 26:249–269

Table 3 Summary of randomized controlled trials of EUS-BD versus ERCP or PTBD
AuthorInterventionnTechnical success (%)

Clinical success (%)

Adverse events (%)

Stent patency

Paik [27]EUS-BDERCP
EUS-BDERCP
EUS-BDERCP
EUS-BDPTBD
EUS-BD
PTBD

61
61
14
14
33
34
13
12
34
32

93.8
90.2
92.8
100
90.9
94.1
100
100
94.1
96.9

90.0
94.5
100
92.8
97.0
91.2
100
100
87.5
87.1

6.3a
19.7
0
0
21.2
14.7
15.3
25
8.8a
31.2

208 days
165 days
379 days
403 days
182 days
170 days––––

Park [28]Bang [29]Artifon [36]
Lee [35]

ERCP endoscopic retrograde cholangiopancreatography, EUS-BD endoscopic ultrasound-guided biliary drainage, PTBD percutaneous transhepatic biliary drainagea
P < 0.05

conventional ERC is unsuitable), bile duct stones, biliary
stricture with chronic pancreatitis, post-liver transplantation biliary stricture, or IgG4-associated cholangitis [15,16, 18, 34]. However, there are few case reports, and thelong-term outcomes are unclear. Thus, the indications for
EUS-BD should be determined.
A randomized controlled trial of PTBD (n = 32) versus EUS-BD (n = 34) showed similar technical success(96.9% vs. 94.1%) and clinical success (87.1% vs.
87.5%) rates, but PTBD had a signiﬁcantly higher
adverse event rate (31.2% vs. 8.8%; P = 0.022) andrequired more re-interventions (0.93 vs. 0.34; P =0.020) [35]. A prospective study of 25 cases reported
similar treatment efﬁcacy and safety rates between
PTBD and EUS-BD [36]. Another retrospective studyof 41 cases concluded that EUS-BD showed better outcomes than those of PTBD [37]. A randomized controlled study comparing EUS-CDS with surgical bypass
in 29 cases reported similar technical success, clinicalsuccess, and survival rates and quality of life [38].
Sharaiha et al. [39] performed a meta-analysis of 483
cases and found that whereas the technical success rates
were similar (OR 1.78; 95% CI 0.69–4.59), EUS-BD
demonstrated better clinical success (OR 0.45; 95% CI
0.23–0.89) and adverse event (OR 0.23; 95% CI 0.12–0.47) rates compared with PTBD. Although EUS-BD
has equivalent or better outcomes than percutaneous or
surgical approaches, a larger-scale prospective comparative study is necessary to acquire sufﬁcient evidence.
Although the indications for EUS-BD will likely
change as techniques advance, it is important to determine
the indications by considering the condition of the patientsand the skill and experience of the endoscopist. In addition, EUS-BD for non-established indications should be
evaluated in clinical trials, not in clinical practice.

Q3. What are the contraindications for EUS-BD?

Contraindications for EUS-BD include conditions
that prevent visualization of the bile duct by EUS,
intervening vessels and/or other organs, bleeding
tendency, and/or excess ascites.
Mean voting score (range): 8.4 (7–9)
Although there is no clear evidence of contraindications
for EUS-BD, they are similar to those of EUS-FNA and
PTBD. In patients with excess ascites, a mature ﬁstulacannot be created after EUS-BD, and there is a risk ofperitonitis due to leakage of bile and intestinal contents.
Although there is no clear deﬁnition of the amount of
ascites, EUS-BD should not be performed in cases withexcess ascites or ascites present in the puncture route. In
addition, the indications for EUS-BD should be carefully
assessed even in cases with a small amount of ascites orwithout ascites in the puncture route. Evaluation of thegeneral condition of the patient during EUS-BD is important because of the potential need for surgical intervention
due to unsuccessful EUS-BD or adverse events. EUS-BD
should not be used in patients with poor conditions without careful consideration and is contraindicated forpatients who have or are suspected to have tumor invasionin the puncture site.
There is no clear evidence of the utility and safety of
EUS-BD in patients on antithrombotic agents. In the 2012
Guidelines for Gastroenterological Endoscopy in Patients
Undergoing Antithrombotic Treatment of the Japan Gastroenterological Endoscopy Society [40], EUS-FNA isclassiﬁed as having a high risk of bleeding. Thus, EUSBD should also be considered to have a high risk of

J Hepatobiliary Pancreat Sci (2019) 26:249–269

bleeding. Among patients who underwent EUS-FNA, theincidence rates of bleeding in those on aspirin/non-steroid
anti-inﬂammatory drugs, low-molecular-weight heparin,
and controls were 0% (0/26), 33.3% (2/6), and 3.7% (7/190), respectively. Therefore, the bleeding rate was not
signiﬁcantly higher in the aspirin/non-steroid anti-inﬂammatory drug group [41]. However, in a large-scale analysis
of PTBD using the Japanese DPC database of 34,606
cases [42], the rate of severe hemorrhage was signiﬁcantly
higher in patients on compared with those not on antithrombotic agents (OR 1.87; 95% CI 1.14–3.05; P =0.013).

Q4. What are the short-term outcomes of EUS-BD?

The technical and clinical success rates of
EUS-BD in experienced centers are ≥90%.
Mean voting score (range): 8.1 (5–9)

The short-term outcomes of EUS-BD include the rates oftechnical and clinical success. Adverse events aredescribed in Q6. In general, technical success is deﬁned as
successful biliary drainage as planned and clinical successas relief of jaundice and cholestasis.
The success rates of EBD, which is the ﬁrst-choice procedure for biliary drainage, and PTBD in patients in whom
ERC would be problematic are high. The technical and clinical success rates of CDS and HGS are also ≥90% [13, 34,43]. Two previous systematic reviews [44, 45] reported
technical success rates of 94.71% and 90% and a clinicalsuccess rate of 91.66%. EUS-HGS and EUS-CDS have
similarly high technical and clinical success rates. In a multicenter retrospective study of 64 Japanese patients who
underwent EUS-BD (44 CDS, 20 HGS) [34], the technicalsuccess rate was 95% for both EUS-CDS and EUS-HGS.
These results are similar to those among non-Japanesepatients. In a recent systematic review [46], technical success rates of CDS and HGS were 94.1% and 93.7%, respectively. Clinical success rates were also comparable: 88.5%
in CDS and 84.5% in HGS (Table 4).
In EUS-BD other than transmural drainage, the successrate of EUS-RV, which converts to a transpapillary
approach after EUS-guided biliary access, is 82% [47].
The success rate of the intrahepatic bile duct approach is76%, which is lower than that of the extrahepatic bile
duct approach (85%). Prior studies involved patients withnot only malignant biliary obstruction but also those withbile duct stones, and the lower success rate was due toguidewire manipulation to pass the biliary stricture or

255
Table 4 Summary of technical and clinical success rates of EUSBD

EUS-CDS [46]EUS-HGS [46]EUS-RV [47]EUS-AG stenting [9, 15, 43, 49–52]

Technical
success (%)

Clinical
success (%)

94.1
93.7
82
83

88.5
84.5
–
–

AG antegrade, CDS choledochoduodenostomy, EUS endoscopic
ultrasound, HGS hepaticogastrostomy, RV rendezvous

ampulla [48]. In studies of EUS-AGS [9, 15, 43, 49–52],
the success rate was 83%, similar to that of EUS-RV, butconversion to transmural biliary drainage was reported incases in which the guidewire could not be manipulated
across the biliary stricture [51]. However, those results
were reported by experienced endoscopists, and the success rate was lower in a less-experienced center [16], suggesting publication bias. Regarding the learning curve of
EUS-BD, a mortality rate of 10% during the initial phase
was reported [18]. A single center study in Thailand of 31
cases over 5 years reported a technical failure rate of 38%
during the initial 3 years, compared with 11% during thelast 2 years. The adverse event rate decreased from 54%
to 22% [53], suggesting a steep learning curve for EUSBD, which should be taken into consideration when introducing EUS-BD to new centers.
Due to the difﬁculty of biliary cannulation in EBD,
comparative studies of the short-term outcomes of EUSBD and EBD for malignant distal biliary obstruction havebeen performed. A multicenter retrospective study [43]showed similar technical success and adverse event rates
between 104 EUS-BD cases (68 EUS-CDS and 36 EUSAGS cases) and 104 EBD cases (93.26% vs. 94.23% success rate and 8.65% vs. 8.65% adverse event rate) and asigniﬁcantly higher success rate for EUS-BD in cases withduodenal stenosis compared with EBD. A Japanese single-center retrospective study [25] compared EUS-CDS (n= 26) and EBD (n = 56) performed for primary drainageof malignant distal biliary obstruction. Whereas the clinical success rates were similar (96.2% vs. 98.2%), the procedure time of EUS-CDS (19.7 min) was shorter than thatof trans-papillary drainage (30.2 min). Both studies
reported no post-procedural pancreatitis resulting from
EUS-BD. Comparative data of EUS-BD and ERCP are
shown in Table 3. The type of adverse events of EUS-BD
and ERCP differ but the adverse event rates were comparable or even lower in EUS-BD in randomized controlled
trials [27–29]. While post-ERCP pancreatitis is a major
adverse event after ERCP, bile leak is a potential severe
adverse event after EUS-BD.

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Therefore, EUS-BD can be a ﬁrst-line option, irrespective of the difﬁculty of ERC. Prospective studies
in Japanese expert centers have reported favorable
short-term outcomes [23, 24]. However, because theevidence supporting the use of EUS-BD as the primary drainage procedure is insufﬁcient, further clinical studies should be conducted in patients other thanthose in whom ERC is technically or clinically difﬁcult or impossible.

Q5. What are the long-term outcomes of EUS-BD?
The few studies on the mid- and long-term outcomes of EUS-BD reported a stent patency of 3–
6 months.
Mean voting score (range): 8.1 (5–9)
Because EUS-BD is a relatively new procedure, mostprevious studies have focused on the technical successand procedure-related adverse event rates, whereas few
have evaluated the long-term outcomes. Prior studies
using various drainage routes and stent types found stentocclusion rates of 16% (19% for CDS, 13% for HGS)and stent patency of 3–6 months (Table 5) [11, 18, 23,
24, 26, 34, 54–67]. In EUS-RV or EUS-AGS, the biliary drainage route is similar to that of transpapillarydrainage, and thus the mid- and long-term outcomes are
expected to be similar to transpapillary drainage.
The stent occlusion rate (stent dysfunction or re-intervention) is reportedly 15% (70/434 cases) [11, 18, 23, 24,
26, 34, 54–67]. There is no signiﬁcant difference in thestent occlusion rate between CDS (19%) and HGS (13%).
The causes of stent obstruction and dysfunction, unlike
those of EBD, are principally non-neoplastic, including
stent dislocation or biliary sludge.
Although comparison of stent patency results amongstudies is difﬁcult due to use of different terminology
and assessment criteria, the stent patency after EUS-BD
is 3–6 months [11, 18, 23, 24, 26, 34, 54–67].
A Japanese study [34] reported a mean time to stent
dysfunction of 96 days: 103 days for EUS-CDS and
62 days for EUS-HGS. There was no signiﬁcant difference in mean stent patency between covered self-expandable metallic stents (SEMSs, 72 days) and plastic
stents (97 days). Park et al. [13] reported a mean stentpatency of 133 days: 152 days for CDS and 132 daysfor HGS. However, EUS-BD resulted in a longer
patency than did EBD in cases with duodenal stenosis
or an indwelling duodenal stent [26], with EUS-HGS
showing a longer patency than that of EUS-CDS [68].

J Hepatobiliary Pancreat Sci (2019) 26:249–269
Table 5 Long term outcomes of EUS-BD
Occlusion rate of stentTotal
16% (95% CI 13–20%)
According to the procedure
EUS-CDS
19% (95% CI 15–25%)
EUS-HGS
13% (95% CI 9–18%)
According to the stent type
Plastic stent
28% (95% CI 21–38%)
Covered SEMS
14% (95% CI 10–20%)

Patency period

99–272 days
62–216 days
97–272 days
72–216 days

CDS choledochoduodenostomy, CI conﬁdence interval, EUS endoscopic ultrasound, HGS hepaticogastrostomy, SEMS self-expandable
metallic stentHara et al. [23, 24] conducted two clinical studies of
EUS-CDS as the initial biliary drainage modality using aplastic stent and covered SEMS. Although these were notrandomized controlled studies, they involved the same subjects and institution, enabling comparison of the long-term
outcomes of EUS-CDS between plastic stents [23] and covered SEMSs [24]. The occlusion rate of plastic stents was
53%, compared with 11% for covered SEMSs, suggestingthat covered SEMSs are superior in terms of stent patency.
No study has evaluated EUS-BD re-intervention forstent occlusion or dislocation. When stent occlusion
develops, stent replacement, stent-in-stent, and/or stentcleaning via EUS-BD are performed in many cases [23,24, 66]. It is necessary to assess the safety and efﬁcacy
of EUS-BD as the initial procedure, as well as for re-intervention.
There is no standardized method for assessing the outcomes of EUS-BD; this hampers comparison of results
among studies. EUS-BD includes various procedures;thus, standardized criteria for assessing the outcomes(safety and efﬁcacy) are needed. In addition, large-scale
multicenter prospective studies of the short-term andlong-term outcomes should be conducted to avoid publication bias. The short- and long-term outcomes aredetailed in this section. However, standardization of theprocedure and development of novel devices will signiﬁcantly change the outcomes, and thus periodic updatingof the guidelines is required.

Q6. What are the adverse events of EUS-BD?

Adverse events of EUS-BD include bile leakage,
stent misplacement, hemorrhage, perforation, andperitonitis.
Mean voting score (range): 7.8 (5–9)

J Hepatobiliary Pancreat Sci (2019) 26:249–269

A pooled analysis of early adverse events among studies
involving ≥20 cases yielded an incidence of early adverse
events of 14.6% (100/755 cases) [12–18, 34, 48, 51, 67,
69–77]. The summary below includes all adverse events
reported in each study (Table 6).
The incidence of early adverse events of EUS-CDS,
including biliary leakage (2.8%), stent migration (2.8%),
hemorrhage (2.5%), perforation (1.4%), and bile peritonitis (1.4%), was 13.9% (20/144 cases) [13, 16, 18,34, 69]. Other adverse events included acute cholangitis[16], biloma [16], pneumoperitoneum [34], bilio-arterial
ﬁstula [18], sepsis [18], abdominal pain [59], duodenal
perforation [61], hemobilia [23], acute cholecystitis [63],and double punctures of the duodenum [78]. Mortalities
were also reported [18].
The incidence of early adverse events of EUS-HGS,
including hemorrhage (3.7%), bile leakage (2.8%),
biloma (2.6%), stent migration (1.6%), stent misplacement (intrahepatic, intraperitoneal) (1.2%), intrahepatic
hematoma (1.2%) and sepsis (1.2%), was 18.2% (45/247 cases) [13, 16, 18, 34, 67, 69–71]. Other adverse
events included perforation [16], abscess [16], acutecholangitis [34], pneumoperitoneum [18], intrahepatic
hematoma [18], peritonitis [70], pseudoaneurysm of thehepatic artery [79], and biliary vomiting [80]. Mortalities (2.0%) and cases of transfer to laparotomy (0.8%)
were also reported [18].
The incidence of early adverse events of EUS-RV,
including acute pancreatitis (2.7%), pneumoperitoneum(2.2%), bile peritonitis (1.4%), and hemorrhage (0.5%),
is 12.4% (45/364 cases) [12, 14, 15, 17, 48, 51, 72–77]. Other adverse events include perforation, hemorrhage (3.7%), bile leakage (2.8%), biloma (2.6%), stentmigration (1.6%), stent misplacement (intrahepatic,
intraperitoneal) (1.2%), intrahepatic hematoma (1.2%),and sepsis (1.2%). Perforation, leakage of contrast medium around the hepatoduodenal ligament, acute cholangitis, heart failure, respiratory failure, sepsis, andaspiration pneumonia have also occurred. Mortalities
were also reported [14].
There were nine mortalities among a case report[81] and a series of ≥20 cases [14, 18, 37]. The
causes of morality were, for EUS-CDS, bile peritonitis and sepsis in three cases each [18], for
EUS-HGS, sepsis due to stent dislocation and biliary
peritonitis due to guidewire perforation [37, 81], andfor EUS-RV, one sudden death 4 days after theprocedure [14].
These results should be interpreted with caution sincemost procedures were performed by experts and there
might be overlapping cases, which might cause somebiases.

257
Table 6 Adverse event of EUS-BD
Incidence
EUS-CDS
Bile leakage
Stent migration
Bleeding
Perforation
Peritonitis
EUS-HGS
Bleeding
Bile leakage
BilomaStent migration
Stent inward migration (IHBD, peritoneal
cavity)Liver hematoma
SepsisEUS-RV
Acute pancreatitis
Pneumoperitoneum
Biliary peritonitis
Abdominal pain
Bile leakage
Bleeding

13.9% (20/144)
2.8%
2.8%
2.5%
1.4%
1.4%
18.2% (45/247)
3.7%
2.8%
2.6%
1.6%
1.2%
1.2%
1.2%
12.4% (45/364)
2.7%
2.2%
2.2%
1.9%
1.4%
0.5%

CDS choledochoduodenostomy, EUS endoscopic ultrasound, HGS
hepaticogastrostomy, IHBD intrahepatic bile duct, RV rendezvous

CQ1. How can we select the EUS-BD procedure?

EUS-BD procedures are selected according to
the patient’s clinical condition, location of the bile
duct obstruction, presence of duodenal obstruction, and gastrointestinal and biliary reconstruction.
[Recommendation level 2, evidence level D]
Mean voting score (range): 8.4 (7–9)

EUS-BD includes EUS-CDS, EUS-HGS, EUS-AGS, and
EUS-RV; the appropriate procedure should be selectedbased on their characteristics, location of the bile ductobstruction, presence of duodenal obstruction, gastrointestinal and biliary reconstruction, and the condition of thepatient. EUS-CDS is not indicated for hilar biliary obstruction, and thus EUS-HGS, EUS-AGS, or EUS-RV should
be used. If a transpapillary approach is difﬁcult due toduodenal obstruction or ampullary invasion, EUS-RV is
not indicated. A retrospective study by Ogura et al. [68]suggested that EUS-HGS showed better stent patency (HR258

0.391, P = 0.045) in cases with duodenal obstruction,
while EUS-CDS was associated with adverse events, inparticular reﬂux cholangitis (OR 10.285, P = 0.012). Figure 3 shows the suitability of the various EUS-BD procedures according to the condition of the patient. In addition,
EUS-guided gallbladder drainage can be performed if bile
duct puncture is unsuccessful, and it can achieve biliary
drainage through the cystic duct. However, EUS-guided
gallbladder drainage can be performed only in cases withthe patent cystic duct, which should be conﬁrmed on EUS
prior to the procedure [82]. In contrast, in cases in which
several approaches are possible, no comparative study has
been reported, warranting further research.
Park et al. reported an algorithm for selection of the
EUS-BD procedure. According to this algorithm, EUS-RV
is the ﬁrst choice for cases with failed ERCP but with anaccessible ampulla, whereas EUS-HGS or CDS is the ﬁrst
choice for cases with duodenal obstruction depending on
the location of the biliary obstruction. Use of the algorithm
yielded a success rate of >90% [51]. Poincloux et al. based
procedure selection on the clinical conditions, resulting in asimilar safety proﬁle and success rate to those reported byPark et al. [18]. According to the algorithm developed by
Khashab et al., EUS-RV should be used for malignant biliary obstruction after failed ERC, and if EUS-RV fails,
EUS-CDS/HGS is to be performed. The two procedures
had similar effectiveness and safety proﬁles [76]. Weilert[83] developed an algorithm, which selected EUS-AGS
using a transgastric intrahepatic bile duct approach forpatients with failed ERCP or, if EUS-AGS fails, thenJ Hepatobiliary Pancreat Sci (2019) 26:249–269

EUS-HGS. EUS-CDS was performed if EUS-HGS failed
or proved difﬁcult. The intrahepatic bile duct approach was
effective in 80% of cases. Iwashita et al. [50] reported the
efﬁcacy and safety of EUS-AGS in patients with a surgically altered anatomy. Sirpum et al. [30] performed a systematic review of EUS-BD in patients with a surgicallyaltered anatomy and found that EUS-BD after failed ERCP
was as safe and effective as in those with a normal anatomy. However, the access route of EUS-BD in patientswith a surgically altered anatomy is often limited to the left
intrahepatic bile duct, and EUS-HGS may not be feasible inpatients with surgical reconstruction. In addition, EUS-RV
requires access to the papilla, which can be difﬁcult. Basedon these ﬁndings, EUS-CDS/HGS, EUS-AGS, or EUS-RV
can be used for patients with a regular anatomy without
duodenal obstruction; EUS-CDS/HGS or EUS-AGS can be
performed in those with duodenal obstruction. The potential
adverse events and patient condition described in Q6 must
be considered when selecting a procedure.
Selection of EUS-CDS or EUS-HGS depends on thelocation of the bile duct obstruction. Prachayakul and
Aswakul [84] reported that HGS is applied for hilar biliary
obstruction and CDS for distal biliary obstruction. The technical success, clinical success, and adverse event rates were95.5%, 90.5%, and 9.5%, respectively. Gupta et al. [85]found no difference in the success and adverse event rates
between EUS-CDS and EUS-HGS. In contrast, whereas
both EUS-CDS and EUS-HGS can be used in patients withcombined duodenal and distal biliary obstruction, Dhir et al.
[86] showed in a retrospective study that EUS-HGS has aFig. 3 Flowchart of selection of various EUS-BD procedures. EUS endoscopic ultrasound, EUS-AGS EUS-guided antegrade stenting, EUSCDS EUS-guided choledochoduodenostomy, EUS-HGS EUS-guided hepaticogastrostomy, EUS-RV EUS-guided rendezvous technique, SDA
supraduodenal angle

J Hepatobiliary Pancreat Sci (2019) 26:249–269

signiﬁcant risk of adverse events. Therefore, EUS-CDS may
be the ﬁrst choice for patients with combined duodenal anddistal biliary obstruction if the duodenal bulb is intact.
The patient’s condition should be considered whenselecting an EUS-BD procedure. The location of biliary
obstruction, presence of duodenal stricture, and reconstruction method in cases with a surgically altered anatomy
should be evaluated by contrast enhanced computed tomography (CT), magnetic resonance imaging (MRI)/magnetic
resonance cholangiopancreatography (MRCP), upper endoscopy, and surgical records. In addition, based on the low
adverse event rate, if either EUS-HGS or EUS-CDS can beused, EUS-CDS should be the ﬁrst choice. Because bothprocedures are performed endoscopically, patient preference
is not an issue. Moreover, the procedure is covered by publichealth insurance in Japan; thus, payment/reimbursement is
not a consideration when selecting the EUS-BD procedure.
CQ2. Which endoscope is recommended for EUS-BD?

Only convex-type EUS scopes can be used for
EUS-BD.
[Recommendation level 1, evidence level C]
Mean voting score (range): 8.4 (7–9)
Several studies have used a convex (including linear)-type
EUS scope. A radial-type EUS scope cannot visualize theneedle route and thus is not suitable for EUS-BD or EUSFNA. No prior study has directly compared EUS scopes.
A forward-viewing convex-type EUS scope is reportedly
useful for EUS-CDS [24, 87]. No other types of EUS
scope can be used, and so patient preference is not a consideration.

CQ3. Which needle is recommended for EUS-BD?

A 19-G FNA needle is recommended.
[Recommendation level 1, evidence level B]
Mean voting score (range): 8.7 (7–9)
Following needle puncture, the procedure is conductedusing a guidewire that passes through the puncture needle.
Therefore, use of a 19-G FNA needle is recommended
and has been used in many previous studies. A 22-G
FNA needle may facilitate puncture of a smaller bile duct.
However, a smaller guidewire (0.021 or 0.018 inches)
does not allow device insertion, resulting in a lower

259

success rate. Thus, a thin guidewire should be exchanged
for a 0.025- or 0.035-inch guidewire to complete the procedure. Whereas use of a needle knife is effective in caseswith difﬁcult puncture or mechanical dilatation [13, 23,
24, 85], the adverse event rate is higher [13], and thus
routine use of a needle knife is not recommended. In
Japan, there is no commercially available access needle
for EUS-BD, but a study using the needle knife has been
performed outside of Japan [88]. The needle knife has aneedle-shape stylet, and its tubular blunt outer sheath protects and facilitates manipulation of the guidewire. However, the needle knife has less ability for puncture and is
not yet used globally.
In summary, a 19-G EUS-FNA needle is currently
recommended for EUS-BD. A puncture needle speciﬁcally designed for EUS-BD is not commercially available, and guidewire insertion through the EUS-FNA
needle is not ofﬁcially recommended. Therefore, development of needles for EUS-BD is required. The patientis unaware of the puncture needle used for EUS-BD
but would prefer it to be effective and safe.
CQ4. Which guidewire is recommended for EUS-BD?

A 0.035-inch or hard-type 0.025-inch guidewire isrecommended for ERCP.
[Recommendation level 2, evidence level C]
Mean voting score (range): 8.4 (7–9)
Because no previous study has compared guidewires for
EUS-BD, we evaluated those used in previous reports.
Whereas a 0.035-inch guidewire was mainly used in thepast, a stiff 0.025-inch guidewire is now increasingly
utilized for EUS-BD, particularly in Japan. A shorthydrophilic guidewire is reportedly useful for EUS-RV[74].
If a 22-G FNA needle is selected, a 0.021- or
0.018-inch (small diameter) guidewire is used. However,guidewire manipulation is difﬁcult and does not enabledevice insertion, hampering EUS-BD. Therefore, a small
diameter guidewire should be exchanged for a 0.025- or
0.035-inch guidewire, which results in additional cost.
There is no patient preference for guidewires, and so
the guidewire should be selected based on its advantages and disadvantages. Coated guidewires are currently
used for ERCP; these have a risk of shearing and fracture when passed through a EUS-FNA needle. No
guidewire has been approved for EUS-BD, and so a
guidewire with a good safety proﬁle and high maneuverability is needed.

260

CQ5. Which dilatation device is recommended for
EUS-BD?

A bougie dilator and balloon dilator are recommended, and a co-axial electric cautery dilator
can be used.
[Recommendation level 2, evidence level C]
Mean voting score (range): 8.2 (6–9)
Dilatation of a ﬁstula is an important but difﬁcult stepduring EUS-BD and facilitates insertion of various
devices including stents. EUS-BD can be unsuccessful
due to failure of this step. Mechanical dilatation using abiliary dilatation catheter (bougie catheter) or balloon
dilator or cautery dilation using a co-axial cautery dilator is performed [71, 89–93]. Although dilatation of aﬁstula using an electric cautery device is technicallyeasy, it has risks of bleeding, perforation, penetration,and incorrect puncture. Therefore, an electric cautery
device should be used if a non-cautery device is noteffective. Use of a non-coaxial needle knife is associated with an increased adverse event rate and thus notrecommended [13, 94]. Overdilation of the ﬁstula may
increase the risk of bile leak and the type and size of
dilators should be selected according to the stent. No
device has been approved by the regulatory authority,and thus development of such a device is needed.
Patients do not have a preference for a dilatation
device; thus, the device can be selected based on its
efﬁcacy and safety.
CQ6. Which stent is recommended for EUS-BD?

A covered SEMS is recommended. A plastic stentcan be considered based on the condition of thepatient.
[Recommendation level 2, evidence level B]
Mean voting score (range): 7.9 (5–9)
Early after its development, the outcomes of plastic stents
with EUS-BD were reported [23, 95]. However, thesestents are associated with risks of bile leakage, ﬁstula,and stent migration [86]. Therefore, covered SEMSs
have been used recently [24, 57, 60, 62, 64, 85, 94, 96–98]. In a retrospective analysis of 121 EUS-BD [94], theuse of a plastic stent was signiﬁcantly associated withadverse event rate (OR 4.95, P = 0.01). Although a dedicated plastic stent for EUS-BD has been developed, theJ Hepatobiliary Pancreat Sci (2019) 26:249–269

rate of adverse events was 17.4% (three mild pain andone moderate bleeding) in a prospective feasibility study[67], which appeared comparable to the conventional
plastic stents. Use of braided-type SEMSs with a highshortening rate requires some technical skill because of
the potential for adverse events, such as stent migration
or dislocation [81, 99]. Therefore, >10 cm SEMSs arerecommended when SEMSs without anti-migration systems are used [100]. To reduce the risk of side branchobstruction or migration, a partially covered SEMS thatis uncovered at the haptic end is used. However, becausesuch stents are prone to migration at the gastric end,
≥10 cm stents are currently used [101]. Plastic stents
reduce the frequency of adverse events, such as segmental cholangitis or liver abscess caused by peripheral bile
duct obstruction [67]. Studies of a biﬂanged lumen-apposing metal stent (AXIOSâ, Boston Scientiﬁc, Marlborough, MA, USA) for EUS-CDS [102–105] and of othertypes of dedicated stents for EUS-CDS or EUS-HGS
have been performed in Korea [65, 91, 106]. In aprospective multicenter study of a lumen-apposing metal
stent with cautery-enhanced delivery system [107], EUSCDS was technically successful in 100% and jaundice
resolved in 95%. Of note, there were no procedure-related adverse events including bile leak. Meanwhile, asump syndrome similar to surgical choledochoduodenostomy was reported after EUS-CDS using a lumen-apposing metal stent [108]. A comparative study of a lumen
apposing metal stent and a conventional stent is warranted. Currently, 8-to-10-mm-diameter and 4-to-6-cmlength SEMSs are used for EUS-CDS and 8-to-10-mmdiameter and 10-to-12-cm-length SEMSs for EUS-HGS.
Patients appear to have no preference regarding stents,and so covered SEMSs are recommended based on their
efﬁcacy and safety. However, in patients in whom covered SEMSs are difﬁcult to use, a plastic stent can beapplied, and therefore stent selection should be based on
the clinical condition of the patient. No stent has been
approved speciﬁcally for EUS-BD by the Japanese regulatory authority, and the development of such a stent isneeded.

CQ7. What supportive treatment is recommended for
EUS-BD?

Antibiotic treatment is suggested for patients withconcomitant cholangitis.
[Recommendation level 2, evidence level D]
Mean voting score (range): 8.3 (7–9)

J Hepatobiliary Pancreat Sci (2019) 26:249–269

The purpose of supportive therapy is to prevent adverse
events. However, no study has assessed the effectiveness ofprophylactic treatment for EUS-BD, and thus no establishedsupportive therapy exists. In the Antibiotic Prophylaxis for
GI Endoscopy guidelines of the American Society of Gastrointestinal Endoscopy [109], the use of antibiotics is recommended in patients with acute cholangitis at the time oftrans-papillary endoscopic biliary drainage, as well as inthose with anticipated incomplete biliary drainage. In the
Antibiotic Prophylaxis for GI Endoscopy guidelines of the
British Society of Gastroenterology [110], antibiotic prophylaxis for prevention of sepsis or cholangitis is recommended for patients with concomitant cholangitis/sepsis at
the time of ERCP, or for those with anticipated difﬁcult or
failed complete biliary drainage. Based on these guidelines,
antibiotic prophylaxis should be performed in patients withconcomitant cholangitis at the time of EUS-BD. In the realworld setting, however, antibiotic prophylaxis is performedin most centers, even for patients without concomitantcholangitis, to prevent potential peritonitis or progression of
peritonitis due to leakage of bile or gastrointestinal contents.
As there is little evidence of the necessity of antibiotic prophylaxis for EUS-BD, further studies are necessary. Antibiotics have potential side-effects and may cause
development of antibiotic-resistant bacteria. Therefore,
patients may have various preferences for antibiotic prophylaxis.

CQ8. What is recommended for the management
procedures after EUS-BD?

Careful observation of patients is required after
EUS-BD, and adequate treatment should be carried out when adverse events are suspected.
[Recommendation level 2, evidence level D]
Mean voting score (range): 8.1 (5–9)
There are no previous reports on the management or observation methods conducted after EUS-BD. Post-procedure
management is required for early detection and diagnosisof adverse events. Monitoring of symptoms and vital signs(blood pressure, pulse rate, body temperature) is required,and when symptoms (fever, abdominal pain, vomiting,hematemesis, and melena) or vital signs suggest adverse
events, physical examination, blood tests, and contrast-enhanced CT should be performed immediately. Abdominal
plain CT the day after EUS-BD is useful for assessing stentposition, biliary drainage status, and adverse events (e.g.
perforation, bile leakage, intra-abdominal emphysema) and261

is performed in many Japanese institutions. When routine
CT is not available, at least a plain radiograph of the abdomen should be performed on the next day of the EUS-BD
procedure. When clinical signs and symptoms as well as
the plain radiograph suggest the possibility of adverse
events such as stent dislocation or perforation, then CT
should be considered. When adverse events are suspected,
the surgeon and radiologist should be consulted regarding
the appropriate treatment. Adverse events such as severe
infection, sepsis, and shock can be lethal if overlooked orleft untreated. Efforts to prevent such severe adverse events
are thus vital.

CQ9. What is recommended for the prevention andtreatment of adverse events of EUS-BD?

There are no established prevention or treatment
protocols for adverse events of EUS-BD. The indications for EUS-BD should be determined basedon the potential adverse events by experienced
endosonographers with the skill and experience toaddress them.
[Recommendation level 2, evidence level D]
Mean voting score (range): 7.4 (5–9)

Because prevention and treatment protocols for adverse
events of EUS-BD have not been established, the procedure should be carried out by experienced endosonographers who can handle the adverse events. Inexperienced
endosonographers may not complete the procedure or
may misplace the stent, which can lead to severe adverse
events. Furthermore, inadequate management of adverse
events can lead to mortality. Safety is important from thepatients’ point of view; the recommendations are acceptable to patients.
Although there are no established prevention or treatment protocols, the following are recommended foradverse events of EUS-BD. EUS-BD can result in two
types of adverse events: those related to the procedureand those following successful EUS-BD. Thus, EUS-BD
should be performed carefully, and patients should beobserved post-procedure to enable timely identiﬁcationand treatment of adverse events.

Adverse events related to the procedure
Although preventing bile leakage and pneumoperitoneum
is difﬁcult, avoiding excess ﬁstula dilation and minimizing

262

the delay between ﬁstula dilatation and stent placement
reduce the risk of bile leakage and bile peritonitis. A single step device of lumen-apposing metal stents with cautery-enhanced system can potentially reduce the risk ofbile leak during EUS-CDS procedure. To prevent retained
pneumoperitoneum, CO2 insufﬂation should also be usedwhenever possible. In addition, the use of covered SEMSs
is recommended to prevent bile leakage. Bile leakage canalso occur in cases with plastic stents if the ﬁstula is larger than the stent diameter. Therefore, the ﬁstula and stentshould be of similar size. Stent release inside the scope
channel can prevent intraperitoneal stent deployment [111,112]. After stent misplacement, an additional stent can beplaced if the guidewire is kept in place. Thus, the guidewire should not be removed until appropriate stent placement is conﬁrmed [113].
To avoid bleeding during EUS-BD, blood vessels along
the puncture route, including collateral ones, should be
evaluated by contrast CT or color doppler EUS imaging.
The EUS scope should not be allowed to compress the surrounding vessels, as this hampers their recognition by doppler EUS imaging. In addition, the use of a needle knife,
which is not coaxial to the indwelling guidewire, should
be avoided. To prevent bleeding from the ﬁstula, the useof a covered SEMS is recommended. Stent placement after
double puncture of the duodenum during EUS-CDS cancause perforation. Therefore, careful observation of theduodenal wall by EUS, endoscopic visualization of theguidewire location, or another method of conﬁrmation
should be performed. Dilatation of the duodenum withwater prior to needle puncture allows visualization of thefolded duodenal mucosa by EUS [114]. In addition, direct
visualization using a forward-viewing convex echoendoscope can prevent double puncture.
To avoid esophageal puncture, which can cause
hemothorax, pneumothorax, mediastinitis, or mediastinal
emphysema, clipping at the esophagogastric junction
enables conﬁrmation of the position of the esophagus
under the ﬂuoroscope. If the esophagus is punctured during EUS-RV, the ﬁstula should not be dilated using a
dilator. Also, if the esophagus is punctured during EUSHGS, the procedure should be terminated. Endoscopic
observation of the puncture site can prevent severe
adverse events during ﬁstula dilatation or stent placement.

Management of adverse events
If severe adverse events such as peritonitis, bile leakage,or pneumoperitoneum are suspected, CT, preferably contrast-enhanced CT, should be performed to determine theappropriate timing of surgery. Procedure-related abdominal pain due to excessive insufﬂation, needle puncture,

J Hepatobiliary Pancreat Sci (2019) 26:249–269

ﬁstula dilation, or stent placement should improve withina short time.
Acute cholangitis is caused by failed stent placement
or by stent misplacement, dislocation, or obstruction. Adequate drainage to manage acute cholangitis should beensured after CT examination. If drainage is successful
and temporary cholangitis conﬁrmed, antibiotic treatment
is effective. If cholangitis in a non-drainage area (segmental cholangitis) is suspected, conservative treatment with
antibiotics is initiated, and additional drainage should be
performed is there is no clinical response. The risk of segmental cholangitis should be considered when placing
covered SEMSs.
If bleeding is observed at the puncture site, endoscopic
hemostasis should be performed. In cases of ﬁstula bleeding, vascular injury should be considered, which can becaused by puncture, dilation, a needle knife, and/or anelectric cautery dilator. Embolization using IVR is needed
if a pseudoaneurysm is suspected on contrast-enhanced
CT. Otherwise, replacement with a larger stent or covered
SEMS can accomplish hemostasis in most cases.
Pleural drainage or surgical interventions are requiredin some cases of hemothorax, mediastinitis, or symptomatic mediastinal emphysema.

CQ10. What is necessary for EUS-BD credentials?

EUS-BD should be performed by an EUS-BD
expert with sufﬁcient clinical experience in both
ERCP and EUS-FNA or by expert endoscopists
under the supervision of an EUS-BD expert.
[Recommendation level 2, evidence level D]
Mean voting score (range): 8.4 (7–9)
During EUS-BD, many devices for ERCP are used, and thepuncturing and endoscope manipulation are similar to thoseused for EUS-FNA. Therefore, EUS-BD should be performed by expert endoscopists with sufﬁcient clinical experience in both ERCP and EUS-FNA. Unexperienced
endoscopists alone may be unable to complete the procedure or may place the stent in the wrong location, possibly
leading to fatal adverse events. The endoscopist should be
able to perform EUS-BD safely and effectively.
It is recommended that endoscopists be trained directly
by an experienced EUS-BD expert; procedure-training
videos and self-training are not sufﬁcient. Observation ofor assistance with the procedure is the ﬁrst step in learning EUS-BD, and trainees should begin with a simple
EUS-BD procedure under the supervision of an EUS-BD
expert. When a complicated EUS-BD is performed by

J Hepatobiliary Pancreat Sci (2019) 26:249–269

trainees, an EUS-BD expert should supervise and replace
the trainee if they cannot complete the procedure. Thus,
EUS-BD should be introduced after a short-term training
program in institutions with experienced EUS-BD experts.
Having an EUS-BD expert supervise the procedure is also
recommended.
The American Society of Gastrointestinal Endoscopy
recommends that endosonographers complete a minimumof 150 supervised EUS procedures, consisting of 75 pancreaticobiliary and 50 EUS-FNA (25 submucosal lesions
and 25 pancreatic lesions) procedures, to achieve competence in all aspects of EUS [115]. The European Societyof Gastrointestinal Endoscopy recommends thatendosonographers learn to handle a convex EUS scope
to visualize the lesion by him/herself prior to learning
EUS-FNA and subsequently undergo training for EUSFNA (involving 30 pancreatic and 20 non-pancreaticlesions) under the supervision of an EUS-BD expert[116]. Oh et al. [117] reported that the procedure time
and the adverse event rate of EUS-HGS stabilized after
33 cases but a learning curve for EUS-BD should befurther investigated.

CQ11. What is recommended for EUS-BD training?

Endosonographers should be trained by experts
at experienced institutions. The training consistsof lectures followed by demonstration of the procedure and hands-on training.
[Recommendation level 2, evidence level D]
Mean voting score (range): 8.4 (5–9)

The recommended training steps are described below. The
technical success and adverse event rates of EUS-BD, andthe management of adverse events, differ between physicians
who have and those who have not undergone the recommended training steps. Patients want to receive EUS-BD by aphysician with sufﬁcient training. However, there is no ofﬁcial training program in Japan.
Step 1: An endoscopy expert with sufﬁcient clinicalexperience teaches the procedure using the standard visualization of convex EUS [118] or videos. Recently, training simulators and models for EUS-BD have beendeveloped [119, 120]; these are useful for acquiring basic
knowledge of the procedure.
Step 2: By visiting an expert institution and participating in live demonstrations of the procedure, the trainees
receive instruction on the requirements for EUS-BD (e.g.
the preparation, process, and roles of medical staff).

263

Step 3: An EUS-BD expert with sufﬁcient clinicalexperience with EUS-BD and sufﬁcient training experience provides hands-on clinical training. First, the trainer
demonstrates the procedure. Next, the trainee participatesin the procedure as an assistant to fully understand eachstep and device manipulation. The trainee subsequently
performs the procedure by her/himself beginning with lesscomplicated procedures under the direct supervision of
the trainer, who will handle any difﬁcult situations.
Supervision by the trainer should continue until thetrainee can perform the procedures by her/himself without
difﬁculty.

CQ12. What is recommended for the institutional
requirements for EUS-BD?

EUS-BD should be performed in institutions
where support from surgeons and radiologists isavailable.
[Recommendation level 2, evidence level D]
Mean voting score (range): 8.1 (5–9)
Each institution should establish a multidisciplinary teamcomprising surgeons, radiologists, IVR experts, nurses, andmedical administrators to support EUS-BD. An EUS-BD
database should be constructed to enable regular evaluationof the outcomes and the adverse event rate in comparison
with other expert centers. If the EUS-BD outcomes areunsatisfactory, or the adverse event rate is high, the underlying reasons should be explored. In addition, consultation
with experienced endoscopists should be considered [121].

CQ13. What are the ethical considerations for EUS-BD?

It is recommended that EUS-BD be performed
carefully after considering the indications andobtaining informed consent from the patient.
[Recommendation level 2, evidence level D]
Mean voting score (range): 8.4 (7–9)
EUS-BD was approved and covered by the Japanesepublic health insurance system in 2012, but evidenceof its safety and long-term outcomes is lacking.
Given the current status of EUS-BD, the indications
should be determined based on four medical ethics
principles [122]: “autonomy”, “non-maleﬁcence”,“beneﬁcence”, and “justice.” The indications for

264

EUS-BD should be discussed with, and the treatment
should be selected by, the patient after providing
fully informed consent [123]. To this end, it is critical to inform the patient of the procedure safety andeffectiveness and of other treatment options. Other
treatment options such as PTBD, ERCP, and surgery
must be fully explained to enable understanding of
the advantages and disadvantages of EUS-BD.
Institutional review board approval for EUS-BD should
be obtained for cases with indications without clinical evidence, those outside the standard treatment protocol, or if
a new device is to be used. It is mandatory to inform thepatient that she/he can withdraw their consent at any time
without unfavorable consequences. The explanations provided to the patient, as well as their consent, must be documented in medical records. Furthermore, EUS-BD mustbe performed by expert endosonographers with sufﬁcientknowledge and experience to handle adverse events or byskilled endoscopists under the supervision thereof.
Acknowledgments These guidelines were created collaboratively
by the Japan Biliary Association (JBA), Japan GastroenterologicalEndoscopy Society, The Japanese Society of Gastroenterology andJapan Pancreas Society. The fee related to the creation of theseguidelines was supported by JBA.

Conﬂict of interest Research grant: Boston Scientiﬁc Japan K.K.,
Century Medical, Inc., Gadelius Medical K.K., Piolax Medical
Devices, Inc., FUJIFILM Medical Co., Ltd. Lecture fee: Boston
Scientiﬁc Japan K.K., Gadelius Medical K.K., Medico’s Hirata Inc.,
Olympus Corporation.

Appendix 1: author’s afﬁliation
Hiroyuki Isayama, Department of Gastroenterology, Graduate School of Medicine, Juntendo University, Tokyo,
Japan; Department of Gastroenterology, Graduate Schoolof Medicine, The University of Tokyo, Tokyo, Japan;
Yousuke Nakai, Department of Gastroenterology, Graduate School of Medicine, The University of Tokyo, Tokyo,
Japan; Takao Itoi, Department of Gastroenterology andHepatology, Tokyo Medical University, Tokyo, Japan;
Ichiro Yasuda, Third Department of Internal Medicine,
University of Toyama, Toyama, Japan; Hiroshi Kawakami, Division of Gastroenterology and Hepatology,
Department of Internal Medicine, Faculty of Medicine,
University of Miyazaki, Miyazaki, Japan; Shomei Ryozawa, Department of Gastroenterology, Saitama Medical
University International Medical Center, Saitama, Japan;
Masayuki Kitano, Second Department of Internal Medicine, Wakayama Medical University, Wakayama, Japan;
Atsushi Irisawa, Department of Gastroenterology, Dokkyo
Medical University, Tochigi, Japan; Akio Katanuma,

J Hepatobiliary Pancreat Sci (2019) 26:249–269

Center for Gastroenterology, Teine-Keijinkai Hospital,
Sapporo, Japan; Kazuo Hara, Department of Gastroenterology, Aichi Cancer Center Hospital, Nagoya, Japan;
Takuji Iwashita, First Department of Internal Medicine,
Gifu University Hospital, Gifu, Japan; Naotaka Fujita,
Miyagi Health Check-up Plaza, Sendai, Japan; Kenji
Yamao, Department of Gastroenterology, Narita Memorial
Hospital, Nagoya, Japan; Masahiro Yoshida, Department
of Hepato-Biliary-Pancreatic and Gastrointestinal Surgery,
School of Medicine, International University of Healthand Welfare, Ichikawa, Japan; Kazuo Inui, Department of
Gastroenterology, Fujita Health University Bantane Hospital, Nagoya, Japan.

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Appendix 2
The members of the guidelines committee who createdand evaluated these guidelines are listed below.
Guideline creation committee
Chair: Hiroyuki Isayama (Department of Gastroenterology, Graduate School of Medicine, Juntendo University,
Tokyo, Japan).
Vice-Chair: Takao Itoi (Department of Gastroenterology
and Hepatology, Tokyo Medical University, Tokyo,
Japan).
Ichiro Yasuda (Third Department of Internal Medicine,
University of Toyama, Toyama, Japan), Masayuki Kitano(Second Department of Internal Medicine, Wakayama
Medical University, Wakayama, Japan), Atsushi Irisawa(Department of Gastroenterology, Dokkyo Medical
University, Tochigi, Japan), Shomei Ryozawa (Department of Gastroenterology, Saitama Medical University
International Medical Center, Saitama, Japan), Akio Katanuma (Center for Gastroenterology, Teine-Keijinkai
Hospital, Sapporo, Japan), Hiroshi Kawakami (Division of
Gastroenterology and Hepatology, Department of Internal
medicine, Faculty of Medicine, University of Miyazaki,
Miyazaki, Japan), Yousuke Nakai (Department of Gastroenterology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan), Kazuo Hara (Department of
Gastroenterology, Aichi Cancer Center, Nagoya, Japan),Takuji Iwashita (First Department of Internal Medicine,
Gifu University Hospital, Gifu, Japan).
Expert panelist committee
Chair: Naotaka Fujita (Miyagi Health Check-up Plaza,
Sendai, Japan).
Kenji Yamao (Department of Gastroenterology, Narita
Memorial Hospital, Nagoya, Japan), Hiroyuki Isayama(Department of Gastroenterology, Graduate School of
Medicine, Juntendo University, Tokyo, Japan), Takao Itoi
(Department of Gastroenterology and Hepatology, Tokyo
Medical University, Tokyo, Japan), Ichiro Yasuda (Third
Department of Internal Medicine, University of Toyama,
Toyama, Japan), Masayuki Kitano (Second Department ofInternal Medicine, Wakayama Medical University,
Wakayama, Japan), Atsushi Irisawa (Department of Gastroenterology, Dokkyo Medical University, Tochigi,
Japan), Shomei Ryozawa (Department of Gastroenterology, Saitama Medical University International Medical
Center, Saitama, Japan), Akio Katanuma (Center for Gastroenterology, Teine-Keijinkai Hospital, Sapporo, Japan),
Hiroshi Kawakami (Division of Gastroenterology andHepatology, Department of Internal medicine, Faculty of

J Hepatobiliary Pancreat Sci (2019) 26:249–269

Medicine, University of Miyazaki, Miyazaki, Japan),Takuji Iwashita (First Department of Internal Medicine,
Gifu University Hospital, Gifu Japan).
Evaluation committee
Chair: Kazuo Inui (Department of Gastroenterology, Fujita
Health University Bantane Hospital, Nagoya, Japan).
Masanori Sugiyama (Department of Surgery, Tokyo
Rosai Hospital, Tokyo, Japan), Kenjiro Yasuda (Department
of Gastroenterology, Kyoto Second Red Cross Hospital,

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Kyoto, Japan), Keiichi Kubota (Second Department of Surgery, Dokkyo Medical University, Tochigi, Japan).
External evaluation committee
Chair: Tadahiro Takada (Department of Surgery, Teikyo
University School of Medicine, Tokyo, Japan).
Masahiro Yoshida (Department of Hepato-Biliary-Pancreatic and Gastrointestinal Surgery, International University of Health and Welfare, Ichikawa Hospital, Ichikawa,Japan).