"ClipFlap" anchoring method for endoscopic ultrasonography-guided hepaticogastrostomy with a covered self-expandable metallic stent

Efficacy and safety of a fully covered self-expandable metallic stent equipped with square flare in EUS-guided drainage/anastomosis: A multicenter retrospective study

Background and Objectives

Recent technological advances in interventional EUS have improved EUS-guided drainage/anastomosis (EUS-D/A), yet challenges remain. This study evaluated the safety and feasibility of a square flare fully covered self-expandable metallic stent (SF-FCSEMS) with anti-migration properties for EUS-D/A.

Methods

This retrospective cohort study was performed at 2 academic centers and analyzed patients who underwent SF-FCSEMS placement for EUS-D/A from April 2015 to November 2022. We have used an SF-FCSEMS that has a square flare at both ends that is 4 mm larger in diameter than the stent body, providing an anti-migration effect.

Results

Thirty-six patients (median age: 74 years), 41.6% male, were included. Malignancies accounted for 83.3%. Among the EUS-D/A procedure types, EUS-abscess drainage was performed in 52.8%, EUS-guided gallbladder drainage in 30.6%, and EUS-guided abscess drainage in 16.7%. The technical success rate was 97.2%, and the clinical success rate was 97.1%. The median procedure time was 36 minutes, with puncture tract dilation conducted in all cases. Adverse events occurred in 11.1%; recurrent symptoms were observed in 11.8%, with no migration. SF-FCSEMS removal was performed in 26.5% of patients during the follow-up period, with a median duration of 154 days. The total cost of deploying SF-FCSEMS was approximately 40% less than that of using lumen apposing metal stent.

Conclusions

EUS-D/A with an SF-FCSEMS, which has anti-migration properties, not only was effective and feasible in the present study but also demonstrated a cost advantage.

Propensity score matching analysis for clinical impact of braided-type versus laser-cut-type covered self-expandable metal stents for endoscopic ultrasound-guided hepaticogastrostomy

BACKGROUND

To prevent stent migration during endoscopic ultrasound-guided hepaticogastrostomy (EUS-HGS), intra-scope channel release technique is important, but is unfamiliar to non-expert hands. The self-expandable metal stent (SEMS) is an additional factor to prevent stent migration. However, no comparative studies of laser-cut-type and braided-type during EUS-HGS have been reported. The aim of this study was to compare the distance between the intrahepatic bile duct and stomach wall after EUS-HGS among laser-cut-type and braided-type SEMS.

METHODS

To evaluate stent anchoring function, we measured the distance between the hepatic parenchyma and stomach wall before EUS-HGS, one day after EUS-HGS, and 7 days after EUS-HGS. Also, propensity score matching was performed to create a propensity score for using laser-cut-type group and braided-type group.

RESULTS

A total of 142 patients were enrolled in this study. Among them, 24 patients underwent EUS-HGS using a laser-cut-type SEMS, and 118 patients underwent EUS-HGS using a braided-type SEMS. EUS-HGS using the laser-cut-type SEMS was mainly performed by non-expert endoscopists (n = 21); EUS-HGS using braided-type SEMS was mainly performed by expert endoscopists (n = 98). The distance after 1 day was significantly shorter in the laser-cut-type group than that in the braided-type group [2.00 (1.70-3.75) vs. 6.90 (3.72-11.70) mm, P < 0.001]. In addition, this distance remained significantly shorter in the laser-cut-type group after 7 days. Although these results were similar after propensity score matching analysis, the distance between hepatic parenchyma and stomach after 7 days was increased by 4 mm compared with the distance after 1 day in the braided-type group. On the other hand, in the laser-cut-type group, the distance after 1 day and 7 days was almost the same.

CONCLUSIONS

EUS-HGS using a laser-cut-type SEMS may be safe to prevent stent migration, even in non-expert hands.

The Lambda stenting technique: a new approach to address EUS-guided biliary drainage-associated adverse events

BACKGROUND AND AIMS

EUS-guided biliary drainage (EUS-BD) has been performed increasingly worldwide, especially in patients with malignant tumors in which ERCP is difficult, patients with surgically altered GI tracts, and older patients who are at high risk for surgery. EUS-BD requires high-level skills and has limited options for managing adverse events, particularly when stent migration and cholangitis occur. Adverse events, such as persistent bile leakage from the fistula and continuous reflux from the GI tract, are believed to always have a risk of severe exacerbation that could threaten the patient's life.

METHODS

We encountered 2 cases of stent migrations and 1 case with repeated cholangitis in patients with malignant tumors among the patients who underwent EUS-BD. The migrated stent was visualized under EUS in 2 patients with stent migration, and an EUS-guided FNA needle was used to puncture the mesh of the stent. The cannulation catheter was directly inserted into the mesh of the stent in 1 case with repeated retrograde cholangitis, while the stent was visualized with an endoscope. Subsequently, a guidewire was inserted through the puncture site, and a second metal stent was deployed between the meshes of the first stent, bridging the GI wall again (Lambda stenting technique). All procedures were performed with the patient under general anesthesia, and the patients safely completed the intervention.

RESULTS

Patients' conditions significantly improved after the second stent insertion, allowing for chemotherapy resumption while maintaining their activities of daily living. The second stent remained in place without any migration, and the stent successfully prevented further cholangitis.

CONCLUSIONS

The Lambda stenting technique is considered highly effective for managing stent migration and repeated cholangitis, which is a major EUS-BD adverse event. This procedure helps avoid more invasive surgeries when stent migration and cholangitis occur and contributes to expanding EUS-BD applicability.

Efficacy of a dedicated plastic stent in endoscopic ultrasound-guided hepaticogastrostomy during the learning curve: cumulative multi-center experience

BACKGROUND AND OBJECTIVES

Currently, there are no reports on the learning curve of endoscopic ultrasound-guided hepaticogastrostomy (EUS-HGS) using dedicated plastic stents. Therefore, we evaluated the outcomes of EUS-HGS using dedicated plastic stents at tertiary referral centers during the initial development phase of EUS-HGS.

MATERIALS AND METHODS

Endoscopic retrograde cholangiopancreatography (ERCP) was strictly prioritized over EUS-HGS. Twenty-three consecutive patients treated using EUS-HGS with a 7-Fr dedicated plastic stent over 4 years beginning in 2018 were analyzed retrospectively.

RESULTS

The most common primary disease was pancreatic cancer, and the most common reason for difficulty in ERCP was duodenal obstruction, followed by surgically altered anatomy. The overall technical success rate of EUS-HGS was 95.7% (22/23). One failed case was converted to EUS-guided choledochoduodenostomy. The clinical success rate was 90.9% (20/22). Adverse events (AEs) related to the procedure were observed in four (17.4%) patients, including mild biliary peritonitis in three (13.0%) and mild cholangitis in one (4.3%) patient; all patients received conservative therapy. No serious AEs, such as stent migration, bleeding, or gastrointestinal perforation, were observed. Recurrent biliary obstruction (RBO) was observed in eight (34.8%) patients. Of these, HGS stent replacement was performed in four patients, and other treatments were performed in the remaining four patients. Another four (17.4%) patients did not develop RBO but underwent periodic HGS stent replacement.

CONCLUSIONS

EUS-HGS using a dedicated plastic stent was performed safely even in its initial phase of introduction. The approach using this stent can be useful in case of ERCP failure for biliary decompression because of the high feasibility and low risk of serious adverse events.

A pilot study of Spring Stopper Stents: Novel partially covered self-expandable metallic stents with anti-migration properties for EUS-guided hepaticogastrostomy

BACKGROUND AND OBJECTIVES

EUS-guided hepaticogastrostomy (EUS-HGS) is an effective salvage procedure when conventional endoscopic transpapillary biliary drainage is difficult or fails. However, the risk of stent migration into the abdominal cavity has not been resolved completely. In this study, we evaluated a newly developed partially covered self-expandable metallic stent (PC-SEMS) that has a spring-like anchoring function on the gastric side.

METHODS

This retrospective pilot study took place at four referral centers in Japan between October 2019 and November 2020. We enrolled 37 cases consecutively who underwent EUS-HGS for unresectable malignant biliary obstruction.

RESULTS

The rates of technical and clinical success were 97.3% and 89.2%, respectively. Technical failures included one case in which the stent was dislocated during the removal of the delivery system, requiring additional EUS-HGS on another branch. Early adverse events (AEs) were observed in four patients (10.8%): two with mild peritonitis (5.4%) and one each (2.7%) with fever and bleeding. No late AEs were observed during the mean follow-up period of 5.1 months. All recurrent biliary obstructions (RBOs) were stent occlusions (29.7%). The median cumulative time to RBO was 7.1 months (95% confidence interval, 4.3 to not available). Although stent migration in which the stopper was in contact with the gastric wall on follow-up computed tomography was observed in six patients (16.2%), no migration was observed.

CONCLUSIONS

The newly developed PC-SEMS is feasible and safe for the EUS-HGS procedure. The spring-like anchoring function on the gastric side is an effective anchor preventing migration.

Novel drill dilator facilitates endoscopic ultrasound-guided hepaticogastrostomy

Tract dilation is one of the most difficult stages of endoscopic ultrasound-guided hepaticogastrostomy (EUS-HGS), especially for beginners. To overcome this problem, we applied a special dedicated dilator. Herein, we retrospectively evaluate the safety and usefulness of a novel drill dilator in EUS-HGS. This single-center retrospective study included 20 consecutive patients who underwent EUS-HGS with a novel drill dilator. The tip is 0.77 mm, and it becomes 7F at 3 cm from tip. The track is dilated to 7F by simple clockwise rotation. The technical success rate of both initial tract dilation and stent placement was 20/20 (100%). No cases required additional dilation such as balloon or electric cautery. In 13/20 cases (65.0%), EUS-HGS was performed by beginner endoscopists. Median time required for dilation was 62.5 s (range, 30-144 s). Median procedure time was 13 min (range, 7-25 min). Early adverse events were two cases of mild fever. There was no bile leakage or bleeding. The novel drill dilator appears to be safe and useful for EUS-HGS. As it is not necessary to press the device strongly, there is no pushback during dilation and the scope position is stable. These characteristics facilitate EUS-HGS even for beginners. This device may enable the further development and increased dissemination of EUS intervention.

Measurement of the anchoring force of covered self-expandable and lumen-apposing metal stents for interventional endoscopic ultrasonography

OBJECTIVES

Interventional endoscopic ultrasonography is performed for various situations that require drainage, after which stent migration is the most severe adverse event. Several lumen-apposing metal stents (LAMS) and covered self-expandable metal stents (CSEMS) provide antimigration systems; however, their anchoring ability has not been studied well. Therefore, we measured and compared the anchoring force (ACF) of commercially available LAMS and CSEMS.

METHODS

Anchoring force was measured for five types of LAMS (NAGI, SPAXUS, Plumber, and AXIOS 8 and 10 mm) and seven types of CSEMS (BCL, SHCL, BCG, BPD [four types of HANAROSTENT], HILZO, Niti-S [Spring Stopper], and Wallflex). We created a phantom model for inducing stent migration. It has a rotatable part as a curved fixture, and we measured ACF at angles between 0° and 40°.

RESULTS

The mean ACF at 0° and 20° were NAGI 1.50, 1.84 N, SPAXUS 1.73, 1.72 N, Plumber 2.64, 2.03 N, and AXIOS 3.96, 3.61 N, respectively; and BCL 0.48, 0.53 N, Wallflex 0.53, 0.48 N, SHCL 0.64, 0.73 N, HILZO 1.09, 1.09 N, BCG 1.22, 1.20 N, BPD 1.78, 1.67 N, and Spring Stopper 2.29, 2.51 N.

CONCLUSION

We measured ACF in LAMS and CSEMS with a new phantom model. The highest value among the LAMS was for the AXIOS and among the CSEMS was for the Spring Stopper. Some of the ACF values varied with the direction of pull. These findings may have a significant impact on stent selection for interventional endoscopic ultrasonography, and this model can be used to evaluate newly developed stents.

Practical Tips for Safe and Successful Endoscopic Ultrasound-Guided Hepaticogastrostomy: A State-of-the-Art Technical Review

Currently, endoscopic ultrasound-guided hepaticogastrostomy (EUS-HGS) is widely performed worldwide for various benign and malignant biliary diseases in cases of difficult or unsuccessful endoscopic transpapillary cholangiopancreatography (ERCP). Furthermore, its applicability as primary drainage has also been reported. Although recent advances in EUS systems and equipment have made EUS-HGS easier and safer, the risk of serious adverse events such as bile leak and stent migration still exists. Physicians and assistants need not only sufficient skills and experience in ERCP-related procedures and basic EUS-related procedures such as fine needle aspiration and pancreatic fluid collection drainage, but also knowledge and techniques specific to EUS-HGS. This technical review mainly focuses on EUS-HGS with self-expandable metal stents for unresectable malignant biliary obstruction and presents the latest and detailed tips for safe and successful performance of the technique.

Endoscopic Reintervention for Recurrence of Malignant Biliary Obstruction: Developing the Best Strategy

Drainage therapy for malignant biliary obstruction (MBO) includes trans-papillary endoscopic retrograde biliary drainage (ERBD), percutaneous transhepatic biliary drainage (PTBD), and trans-gastrointestinal endoscopic ultrasound-guided biliary drainage (EUS-BD). With the development of chemotherapy, many MBO cases end up needing endoscopic reintervention (E-RI) for recurrent biliary obstruction. To achieve a successful E-RI, it is necessary to understand the various findings regarding E-RI in MBO cases reported to date. Therefore, in this review, we focus on E-RI for ERBD of distal MBO, ERBD of hilar MBO, and EUS-BD. To plan an appropriate E-RI strategy for biliary stent occlusion for MBO, the following must be considered on a case-by-case basis: the urgency of the drainage, the cause of the occlusion, the original route of drainage (PTBD/ERBD/EUS-BD), the initial stent used (plastic stent or self-expandable metallic stent), and in the case of self-expandable metallic stents, the type used (fully covered or uncovered). Regardless of the original method of stent placement, if the inflammation caused by obstructive cholangitis is severe and/or the patient is in shock, PTBD should be considered as the first choice. Finally, it is important to keep in mind that in many cases, performing E-RI will be difficult.

Usefulness of Routine Plain CT the Day After an Interventional EUS Procedure

BACKGROUND

Interventional endoscopic ultrasound-guided procedures (I-EUS) are widely accepted as salvage procedures in ERCP-failed cases, and to drain fluid collected in the abdominal cavity. Although I-EUS has a relatively high incidence of complications and is severe/fatal in some cases, no follow-up strategy has been established. In our institution, plain computed tomography (P-CT) is performed routinely the day after I-EUS. In this study, we evaluated the usefulness of routine P-CT the day after I-EUS, as a follow-up method, and propose an algorithm.

METHODS

We retrospectively reviewed 81 patients who underwent I-EUS and evaluated the usefulness of P-CT, abdominal X-ray, laboratory data, and symptoms as a follow-up method. An adverse event (AE) was defined as an event requiring any treatment.

RESULTS

Technical success, clinical success, and AE rates were 96.3%, 90.1%, and 18.9%, respectively. In total, 30 patients had abnormal findings among the follow-up methods: 6 cases underwent additional procedures, 8 underwent medical treatments, and 16 were observed. The sensitivity, specificity, and accuracy for detecting AEs were assessed based on P-CT (85.7%, 100%, and 97.5%), X-ray (7.1%, 100%, and 83.5%), laboratory data (71.4%, 83.0%, and 81.0%), and symptoms (92.9%, 86.2%, and 87.3%). The sensitivity and accuracy of the latter two items were as high as those for X-ray, but specificity was lower than those for X-ray and P-CT.

CONCLUSIONS

Routine P-CT the day after I-EUS was useful for detecting complications and deciding to perform an invasive salvage procedure. Symptoms and laboratory data were useful to supplement routine P-CT.

Risk Factors for Stent Migration into the Abdominal Cavity after Endoscopic Ultrasound-Guided Hepaticogastrostomy

Background: Endoscopic ultrasound-guided hepaticogastrostomy (EUS-HGS) is becoming increasingly popular. However, the risk factors for stent migration into the abdominal cavity remain unknown. Methods: Forty-eight patients undergoing EUS-HGS with placement of a long, partially covered self-expandable metallic stent (LPC-SEMS) were studied retrospectively to identify risk factors of stent migration. We determined the technical and functional success rates, and recorded adverse events, including stent migration. Results: EUS-HGS was technically successful in all patients. However, stent migration was evident in five patients (one actual and four imminent, 10%). Stent migration into the abdominal cavity was observed in one patient (2%), and the other four cases required additional procedures to prevent migration (8%). Logistic regression analysis revealed that the risk of stent migration increased as the initial (pre-procedure) distance between the stomach and liver at the puncture site increased (p = 0.012). Conclusions: A longer distance between the stomach and liver at the puncture site increased the risk of stent migration. However, during EUS-HGS, it is difficult to adjust the puncture position. It is important to ensure that the proportion of the stent in the stomach is large; the use of a self-anchoring stent may be optimal.