EUS-guided biliary drainage for difficult cannulation.

EUS-guided biliary drainage (EUS-BD) has been recognized as a new alternative to failed ERCP. The alternatives for failed/impossible ERCP in cases of difficult and selective bile duct cannulation include percutaneous transhepatic BD (PTBD) with precut papillotomy. EUS-BD is reportedly more convenient than PTBD and more successful than precut papillotomy, suggesting that EUS-BD is the next step following failed/impossible ERCP. Copyright:

INTRODUCTION

The transpapillary biliary approach using ERCP is recognized as the most standard biliary drainage (BD) therapy, with reported technical success rates of >90%. However, the procedure may fail due to anatomical and technical reasons such as surgically altered anatomy, upper intestinal obstruction, and duodenal papillary tumor invasion.[123] Percutaneous transhepatic BD (PTBD) has been widely used as an alternative procedure for patients with failed ERCP. However, PTBD involves an external fistula drainage system that drastically decreases patients' quality of life.[456] Another alternative is precut papillotomy, which is generally performed when deep bile duct cannulation fails during ERCP.

EUS-guided BD (EUS-BD) was first reported by Giovannini et al. in 2001;[7] it has gained substantial attention in recent years, and its efficacy has been demonstrated.[89101112] Unlike PTBD, EUS-BD involves an internal fistula between the biliary and gastrointestinal tracts, preserving patients' quality of life. In recent systematic reviews, the technical success rate for EUS-BD has been reported to be >90%,[131415] suggesting its use as the standard treatment for BD in future.

The present study aimed to evaluate the efficacy of EUS-BD compared with that of conventional therapies in patients with failed selective bile duct cannulation.

EUS-BILIARY DRAINAGE VERSUS PERCUTANEOUS TRANSHEPATIC BILIARY DRAINAGE

PTBD has been the most common secondary BD treatment for cases of failed ERCP, but EUS-BD has been widely performed recently. To date, only ten studies have compared the efficacies of EUS-BD and PTBD after failed ERCP,[16171819202122232425] including seven retrospective studies[17181921222325] and three prospective, randomized, controlled trials[162024] (two multicenter and eight single-center studies). Table 1 summarizes the results of these ten studies. Among the 530 patients included in these studies, 282 underwent EUS-BD and 248 underwent PTBD, with similar technical success rates obtained for EUS-BD (91% [256/282]) and PTBD (95% [236/248]). The clinical success rates for EUS-BD and PTBD were 84% (163/195) and 81% (137/169), respectively, in 364 patients in seven studies.[16182122232425] A systematic review and meta-analysis of nine studies[161718192021222324] involving 483 patients found no difference in terms of technical success rate between EUS-BD and PTBD. However, EUS-BD showed a higher clinical success rate and significantly lower complication and reintervention rates than PTBD.[26] Although EUS-BD requires advanced techniques and it should be performed by experienced endoscopists, these results suggest that EUS-BD has several advantages over PTBD.

Table 1

Studies on EUS-guided biliary drainage versus percutaneous transhepatic biliary drainage

References	Study design	Number of patients	Technical success rate (%)	Clinical success rate (%)	Adverse event rate (%)	Reintervention rate (%)
Artifon et al.[16]	Prospective, RCT	EUS-BD: 13PTBD: 12	13/13 (100)12/12 (100)	13/13 (100)12/12 (100)	2/13 (15)3/12 (25)	-
Bapaye et al.[17]	Retrospective	EUS-BD: 25PTBD: 26	23/25 (92)26/26 (100)	-	5/25 (20)12/26 (46)	-
Khashab et al.[18]	Retrospective	EUS-BD: 22PTBD: 51	19/22 (86)51/51 (100)	19/19 (100)47/51 (92)	4/22 (18)20/51 (39)	3/19 (16)23/51 (45)
Bill et al.[19]	Retrospective	EUS-BD: 25PTBD: 25	19/25 (76)25/25 (100)	24/25 (96)20/25 (80)	7/25 (28)9/25 (36)	4/25 (16)15/25 (60)
Giovannini et al.[20]	Prospective, RCT	EUS-BD: 20PTBD: 21	19/20 (95)17/21 (85)	-	7/20 (35)12/21 (60)	-
Sharaiha et al.[21]	Retrospective	EUS-BD: 47PTBD: 13	43/47 (92)11/13 (93)	27/43 (63)3/11 (27)	5/47 (15)11/13 (85)	12/43 (28)10/11 (91)
Torres-Ruiz et al.[22]	Retrospective	EUS-BD: 35PTBD: 31	28/35 (81)28/31 (90)	25/28 (89)19/28 (68)	9/35 (26)20/31 (65)	2/28 (7)8/28 (29)
Sportes et al.[23]	Retrospective	EUS-BD: 31PTBD: 20	31/31 (100)20/20 (100)	25/31 (86)15/20 (83)	5/31 (16)2/20 (10)	2/31 (6)4/21 (19)
Lee et al.[24]	Prospective, RCT	EUS-BD: 34PTBD: 32	32/34 (94)31/32 (97)	28/32 (88)27/31 (87)	3/34 (9)9/32 (28)	11/32 (34)29/31 (94)
Ogura et al.[25]	Retrospective	EUS-BD: 30PTBD: 18	29/30 (97)16/18 (89)	26/29 (90)14/16 (88)	3/30 (10)3/18 (17)	-

RCT: Randomized controlled trial, EUS-BD: EUS-guided biliary drainage, PTBD: Percutaneous transhepatic biliary drainage

Most PTBD cases involve the use of plastic stents, whereas most endoscopists performing EUS-BD prefer metal stents; this difference may be related to adverse events, such as bile leakage and stent occlusion. PTBD is often performed by radiologists, but EUS-BD is performed by endoscopists who have the advantage of immediately shifting to the secondary treatment after ERCP failure. Ngamruengphong et al. reported that the average number of interventions per patient was 3.44 for PTBD and 1.67 for EUS-BD, and that EUS-BD is more cost-effective than PTBD owing to its lower need for reintervention.[27]

In addition, endoscopists can choose among different EUS-BD routes and methods, whereas PTBD has the limitation of drainage route selection and does not offer these options. PTBD requires intrahepatic bile duct dilatation because only the intrahepatic bile ducts are its target. Conversely, EUS-BD can be achieved through both intrahepatic and extrahepatic bile duct approaches, and the selection of an appropriate drainage route may determine treatment effectiveness [Figure 1].

Figure 1

A case of choledocholithiasis, wherein EUS-rendezvous was performed without intrahepatic bile duct dilatation. (a) Puncture the extrahepatic bile duct using a 19G fine-needle aspiration needle under EUS guidance (white arrow). (b) Inject a contrast medium into the extrahepatic bile duct (white arrow) and then, confirm choledocholithiasis (white arrowhead). (c) Lead the guidewire successfully to the papilla side (white arrow) and advance it to the duodenum. (d) While retaining guidewire, remove the EUS scope and insert the ERCP scope to the duodenal papilla. Then, hold the soft parts of guidewire using a snare

A recent meta-analysis revealed no significant difference between the intrahepatic and extrahepatic bile duct approaches regarding efficacy and safety.[14] Tyberg et al. proposed an algorithm for the BD route in EUS-BD after ERCP failure,[28] which suggested that the procedure must be switched to the extrahepatic bile duct approach when drainage from intrahepatic bile ducts is unsuccessful. In this report, the use of multiple access routes and methods resulted in efficacy and safety superior to those reported in other studies. Minaga et al. reported no difference in terms of technical success rates between extrahepatic and intrahepatic bile duct approaches.[29] In addition, when one approach appears significantly challenging, readily switching to the other approach could increase the overall technical success rate.[29]

These studies suggest that EUS-BD is more useful for patients with ERCP failure than PTBD because of its favorable clinical outcomes and lower adverse event and reintervention rates. In addition, the option of selecting the bile duct approach route is considered as an advantage.

EUS-GUIDED BILIARY DRAINAGE VERSUS PRECUT PAPILLOTOMY

According to a meta-analysis on the success rate for ERCP, the selective deep bile duct cannulation rate is approximately 89%, and precut papillotomy is generally performed when deep bile duct cannulation fails.[30] Bile duct cannulation has been successful in >65% of cases, in which precut papillotomy was performed when ERCP failed.[30313233343536] Currently, two precut methods are available: one using a needle knife, and the other using a papillotome. Needle knife precut papillotomy has been performed since the 1980s.[37] The papillotome precutting method was first reported by Goff in 1995 as transpancreatic precut sphincterotomy.[38] A prospective randomized controlled trail study that compared the outcomes of transpancreatic precut sphincterotomy and needle knife precut papillotomy concluded that the former method increases the rate of selective biliary cannulation and shortens the examination time without increasing the risk of complications.[39]

To the best of our knowledge, only two retrospective studies have compared the efficacy of precut papillotomy and EUS-BD in patients with failed bile duct cannulation.[1140] Table 2 summarizes the results of these two studies.[1140] Lee et al. conducted a retrospective, multicenter, cohort study on patients with selective bile duct cannulation failure who underwent precut papillotomy plus EUS-BD or precut papillotomy alone. They showed that the failure rate for ERCP was significantly lower, and technical success rate was higher in the precut papillotomy plus EUS-BD group than those in the precut papillotomy alone group.[40]

Table 2

Studies of EUS-guided biliary drainage versus precut papillotomy

References	Study design	Number of patients	Technical success rate (%)	Complications rate (%)
Dhir et al.[11]	Retrospective	EUS-BD: 58Precut: 144	57/58 (98)130/144 (90) P=0.038	2/58 (3)10/144 (7) P=0.27
Lee A et al.[40]	Retrospective	EUS-BD: 61Precut: 142	58/61 (95)107/142 (75) P<0.001	-

EUS-BD: EUS-guided biliary drainage

In a single-center, retrospective study, Dhir et al. compared technical success and complication rates between EUS-guided rendezvous technique (EUS-RV) and precut papillotomy in patients with failed selective bile duct cannulation and found that the technical success rate was significantly higher in the EUS-RV group (57/58, 98.3%) than in the precut papillotomy group (130/144, 90.3%).[11] There was no significant difference in terms of complication rate between the groups, although one patient in the precut papillotomy group experienced severe pancreatitis requiring prolonged hospitalization.[11]

Taken together, these results suggest that EUS-BD has a higher technical success rate than precut papillotomy. In cases of malignant biliary obstruction caused by carcinoma of the head of the pancreas, distal bile duct, or papilla of Vater; tumor invasion into the papilla of Vater and duodenal stenosis cause challenges while performing precut papillotomy; further, precut papillotomy is associated with a high complication risk. For particularly, such cases, EUS-BD allows the selection of a tumor-free drainage route; therefore, it is considered to be associated with a lower complication risk than precut papillotomy [Figure 2].

Figure 2

A case of failed ERCP for carcinoma of the duodenal papilla. (a) Papillary orifice cannot be recognized due to carcinoma of the papilla of Vater. (b) Puncture the extrahepatic bile duct from the duodenal bulb (white arrow). (c) Followed by cholangiography, advances the guidewire into the hilar bile duct. Then, insert the stent delivery system (white arrow). (d) The stent is deployed completely

Taken together, our literature review suggests that EUS-BD is a more effective treatment than conventional precut papillotomy for patients with failed selective bile duct cannulation.

CONCLUSION

PTBD and precut papillotomy have been often performed in cases of failed selective bile duct cannulation; however, EUS-BD is more convenient than conventional therapies. For EUS-BD to be recognized as a standard therapy in future, more studies confirming these findings are warranted.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.