INTRODUCTION
Gastrointestinal (GI) anastomosis relies on restoring luminal continuity by joining two segments of bowel following surgical resection, and remains a central surgical intervention in the care of patients with malignant and benign diseases[1]. These anastomoses have traditionally been constructed using hand sewing, stapling, and compression-based systems, and have continued to evolve over time with improved efficacy and safety[2].
Endoscopic ultrasound (EUS) has evolved significantly over the past few decades. Initial reports of EUS in the 1980s were mainly focused on locoregional staging of upper GI malignancy, then expanded to include evaluation of pancreatic and biliary disease, subepithelial lesions, and lymphadenopathy. Later on in the 1990s, EUS-guided fine-needle aspiration was introduced enabling tissue sampling making this technique essential for a GI practice[3,4].
Building on these diagnostic advances, therapeutic EUS has since evolved as a vital minimally invasive endoscopic approach for a multitude of pathologies. The introduction of the lumen-apposing metal stent (LAMS) with its dual-flange design able to reliably appose two GI lumens paved the way for EUS-guided anastomosis as a reliable, safe, and reproducible technique. EUS-guided GI anastomosis (EUS-GIA) relies on creating an anastomosis between two adjacent GI lumens under EUS guidance with the goal of either bypassing an obstructed segment or facilitating access to a previously inaccessible segment due to prior surgical intervention[1,5].
Prior to the introduction of EUS-GIA, GI obstruction was traditionally managed with placement of self-expandable metal stents (SEMS) throughout the GI tract. However, SEMS have limited use in complex or postsurgical anatomy. Interventional radiology may sometimes offer an alternative approach when traditional endoscopy fails. EUS-GIA offers significant advantages over traditional endoscopic and fluoroscopic techniques, permitting real-time visualization of adjacent structures and vascular landmarks with high efficacy and safety[4].
EUS-GIA currently covers a growing list of procedures including EUS-guided gastroenterostomy (EUS-GE) for gastric outlet obstruction (GOO), gastrogastrostomy to enable endoscopic retrograde cholangiopancreatography (ERCP) in surgically altered anatomy [EUS-directed transgastric ERCP (EDGE)], and decompression of afferent loop syndrome (ALS). Additional applications include enteroenteric bypass for selected distal obstructions or access to stenosed bilioenteric anastomosis in post-surgical anatomy[4,6,7].
As the experience grows and with further device refinements on the way, EUS-GIA has found itself as an essential minimally invasive alternative to surgery for carefully selected patients. This review will focus on the use of EUS-GIA in current clinical practice specifically relating to procedure-specific technique, outcomes, patient selection, and future directions and knowledge gaps.
LITERATURE SEARCH
We searched MEDLINE, PubMed, EMBASE, JSTOR, and Google Scholar through January 2026, using a combination of free-text and MeSH terms (GI anastomosis, EUS, GOO, EUS-GIA, EUS-directed transgastric ERCP, afferent limb syndrome) joined with Boolean operators for full coverage.
Cross-references were manually identified through the citation lists of selected articles to capture additional relevant publications. Our search yielded 132 articles published predominantly between 2015 and 2026 encompassing original research articles, review papers, meta-analysis, conference proceedings, and relevant book chapters. As this is a narrative review, no ethical approval was required.
CLINICAL INDICATIONS AND SCOPE
Current use of EUS-GIA is driven by two broad clinical needs: Bypass of obstructed GI segments and restoration of endoscopic access in surgically altered anatomy. Among these, the most well-established indication is GOO, particularly in the setting of unresectable malignancy, where EUS-GE enables creation of a bypass between the stomach and the small bowel distal to the obstruction. Compared with enteral SEMS, EUS-GE offers improved long-term luminal patency and lower rates of recurrent obstruction, while avoiding the morbidity associated with surgical gastrojejunostomy[8-10]. Increasing data also support its use in select cases of benign GOO refractory to endoscopic balloon dilation, especially in patients who are poor surgical candidates[9].
Beyond luminal obstruction, EUS-GIA has become a critical tool in the management of patients with surgically altered anatomy. In individuals with Roux-en-Y gastric bypass, EUS-EDGE facilitates access to the excluded stomach and native papilla, allowing standard ERCP for biliary and pancreatic ductal disease with high technical and clinical success[11,12]. Similarly, EUS-guided enteroenterostomy has demonstrated efficacy in ALS by decompressing obstructed limbs and restoring intestinal continuity without the need for reoperation[13]. Additional indications include treatment of bilioenteric anastomotic strictures, management of obstructed enteroenteric anastomoses following surgical reconstruction, and creation of internal bypasses in select cases of distal small bowel obstruction[14].
Essentially, EUS-GIA functions as a minimally invasive alternative to surgery and percutaneous approaches. A multicenter retrospective study evaluated the technical success, clinical success, stent patency, and reintervention rate of 216 patients undergoing EUS-GIA with LAMS for GOO, anastomotic leaks, and endoscopic access in surgically altered anatomy. Technical success was 94.9%, clinical success 93.7%, with a relatively low adverse event rate of 11.1%, and reintervention rate of 7.7%[6]. As this technique becomes more standardized and further long term data emerges, EUS-GIA is poised to become a cornerstone within therapeutic endoscopy.
GOO: EUS-GE
Procedure and technical considerations
EUS-GE relies on creating a transluminal anastomosis between the stomach and a jejunal loop distal to the obstruction. The procedure is typically performed under general anesthesia with fluoroscopic support. The first and most important step is to adequately identify and distend a small bowel loop distal to the obstruction. A nasojejunal tube is typically advanced across the stenosis under endoscopic or fluoroscopic guidance. Saline mixed with contrast and sometimes methylene blue is then infused through the nasojejunal tube to further expand the target loop of small bowel and optimize visualization. Otherwise, without adequate distension, the loop of small bowel becomes unstable increasing the risk of stent misdeployment[15,16]. Once a jejunal loop is adequately distended and is able to be visualized from the stomach with a linear echoendoscope, the endoscopist needs to confirm close apposition, rule out intervening vessels using Doppler, and ensure a stable endoscopic position prior to LAMS advancement. The main technical differences among EUS-GE approaches lie in how the downstream jejunal loop is identified, distended, and stabilized before LAMS deployment. The direct freehand technique involves puncture of the target jejunum using an electrocautery-enhanced LAMS delivery system without prior guidewire placement. Alternatively, a guidewire-assisted method may be used, in which a 19-gauge needle is first advanced into the jejunum, contrast is injected to confirm intraluminal positioning, and a guidewire is placed before tract dilation and stent deployment. Balloon-assisted techniques and the endoscopic ultrasonography-guided double-balloon-occluded gastrojejunostomy bypass (double-balloon–occluded gastrojejunostomy bypass) method use enteric balloons to stabilize and better define the jejunal target, particularly in technically challenging anatomy. Stent deployment is performed under combined EUS and endoscopic visualization. The distal flange of the LAMS is released within the jejunal lumen, followed by controlled retraction to oppose the bowel wall to the gastric wall, and subsequent deployment of the proximal flange within the stomach. Reflux of blue colored fluid through the stent after deployment confirms adequate deployment[16,17].
Several factors affect the technical success of EUS-GE. These include accurate target selection, scope stability, correct stent size, and correct stent deployment. If these steps are not followed carefully, the procedure may result in stent misdeployment, perforation, bleeding, or peritoneal contamination. Stent diameter selection is an essential step as it affects luminal patency, durability, and the potential adverse events. Most reported using 15-mm and 20-mm LAMS, and most centers recommend the 20 mm size whenever the anatomy permits. The larger LAMS size approaches the caliber of a surgical gastrojejunostomy, decreasing the risk of recurrent obstruction and allowing endoscope advancement through the stent if needed in the future. For example, retrograde transjejunal ERCP may be needed for biliary access in these patients in the future. A 15-mm LAMS is still a reasonable alternative especially in tighter working spaces or when the scope stability is a concern (Figure 1)[18,19].
Figure 1 A 72-year-old female with locally advanced pancreatic adenocarcinoma presented with symptomatic gastric outlet obstruction and underwent endoscopic ultrasound-guided gastroenterostomy for palliation.
A: Upper endoscopy demonstrated a severe, malignant-appearing stricture involving the distal duodenal bulb; B: A nasojejunal tube was advanced into the distal duodenum over a guidewire under fluoroscopic guidance; C: A mixture of contrast and water was infused through the nasojejunal tube to distend the small bowel; D: A distended jejunal loop was identified endosonographically from the stomach; E: A 20-mm lumen-apposing metal stent was deployed to create the gastroenterostomy; F: Endoscopic view confirming adequate deployment of the proximal flange within the gastric lumen.
Clinical indications
EUS-GE is primarily used to palliate symptomatic GOO by creating a gastrojejunal bypass with a LAMS positioned away from the tumor or stricture. In malignant GOO, EUS-GE is most often considered when longer-term patency is desired, when the obstruction is long or angulated, or when tumor-related ingrowth/overgrowth is felt to be a high risk for recurrent obstruction. In benign GOO, EUS-GE is generally reserved for refractory disease or for patients in whom surgery is undesirable because of comorbidity or operative risk. Across these indications, contemporary evidence consistently supports EUS-GE as a high-success, durability-oriented approach when performed in experienced centers. Meta-analytic data in mixed benign and malignant cohorts demonstrate pooled technical success rates ranging from 92% to 100% with low overall adverse events[20].
Outcomes, durability, and adverse events
EUS-GE has demonstrated high technical and clinical success in the management of GOO. Pooled analyses encompassing more than 600 patients report a technical success rate around 90%-95% and clinical success of approximately 90%-93%, with pooled re-intervention rates significantly lower than those seen with duodenal stent placement. In one large meta-analysis, EUS-GE showed a technical success rate of about 95.2% and a clinical success rate of 93.3%, while enteral stenting had a slightly higher pooled technical success rate but significantly lower clinical success and higher re-intervention rates (23.6% vs 4%), underscoring better long-term patency with EUS-GE. Re-intervention and stent dysfunction are key performance markers where EUS-GE appears to have an advantage over self-expanding metal duodenal stents[21,22].
EUS-GE has also been compared with surgical gastrojejunostomy. Several meta-analyses of observational cohorts reported a higher technical success of surgical gastrojejunostomy compared to EUS-GE but at the expense of longer hospital stays and with comparable clinical success. EUS-GE has also demonstrated lower pooled adverse event rates, with recurrence/reintervention patterns being comparable[23,24]. A multicenter randomized trial confirmed these findings, with patients undergoing EUS-GE returning to oral intake sooner (median approximately 2 days) and being discharged earlier (approximately 3 days vs approximately 9 days) than surgical gastrojejunostomy patients, along with lower the rate of reintervention and increased quality-of-life scores[25].
While technical and clinical success is high, the risk of adverse events remains relatively high at 12% to 18%. Most complications are attributed to stent deployment with incomplete apposition, with additional concerns include bleeding, peritonitis, and, stent migration or occlusion. It is important to note that most of these concerns can be salvaged endoscopically, and it is essential for the endoscopists to familiarize themselves with salvage techniques and approaches in addition to the technical procedure itself[21].
When compared to duodenal SEMS, EUS-GE is becoming the clear favorite for most patient centered metrics. EUS-GE demonstrated higher clinical success, fewer reinterventions, and a lower adverse event profile, with a longer procedure time compared to SEMS. The main advantage of LAMS lies through bypassing the malignancy entirely, therefore reducing the risk of tumor ingrowth or overgrowth[21].
In brief, current evidence positions EUS-GE as a clear favorite on multiple metrics. While the procedure is more technically demanding, this is likely justified by fewer reinterventions in the future. EUS-GE has consistently demonstrated faster symptom relief, shorter hospital stay, and fewer reinterventions compared with enteral stenting, with a robust safety profile when evaluated against surgical interventions. Larger randomized trials in the future will further clarify the long-term efficacy and cost-effectiveness across multiple indications[26,27].
ERCP IN ROUX-EN-Y GASTRIC BYPASS: THE ROLE OF EDGE
Procedural technique
In patients with Roux-en-Y gastric bypass, reaching the papilla traditionally required a surgical access port or a long enteroscope. EDGE aims at restoring access via the conventional route by enabling access to the remnant stomach using a duodenoscope. A transluminal fistula is created using a LAMS between the gastric pouch (or proximal jejunum) and the remnant stomach enabling access to the papilla using the duodenoscope and the full ERCP toolkit. Multiple studies and meta-analysis have described this technique with a high technical and clinical success rate and a reasonable safety profile[12,28].
It is crucial to review cross-sectional imaging beforehand to verify proximity of the pouch to the remnant stomach and rule out interposing colon. A prior history of Sleeve gastrectomy converted to Roux-en-Y bypass could make access more challenging due to a smaller remnant stomach. Ideally, endoscopists should target the proximal or mid-body of the excluded stomach as the resulting tract is shorter and straighter, making subsequent duodenoscope passage easier. In brief, a tract that allows near-axial duodenoscope passage is favored as more distal puncture sites add angulation and torque, increasing the risk of stent dislodgement during ERCP[29]. It is also important to evaluate for the presence of a spontaneous gastro-gastric fistula using an upper endoscope allowing access to the remnant stomach and completion of the procedure.
The first step lies in accurate identification of the remnant stomach using a linear echoendoscope. The remnant stomach is typically collapsed, hypoechoic, and exhibits the “sand dollar sign”. Once the remnant is identified, a 19-gauge needle puncture followed by contrast and saline injection is used to distend the lumen and confirm intraluminal position. While some endoscopists advance a guidewire into the remnant stomach followed by LAMS placement, we favor a freehand LAMS puncture directly into the distended stomach, releasing the distal flange under EUS visualization. The proximal flange is then released under endoscopic view. Combined endoscopic and fluoroscopic confirmation decreases the risk of misdeployment and the interluminal distance should be less than 1-2 cm to ensure adequate flange apposition[14].
When it comes to stent size selection, the 20-mm LAMS is preferred as it allows passage of a duodenoscope with less resistance during scope exchange compared to a 15-mm stent, which is reserved for cases with a smaller target stomach such as patients with prior Sleeve gastrectomy. If ERCP is planned during the same session, dilation of the tract through the stent is then performed[30].
Following LAMS placement, there are two strategies. In single-session EDGE, ERCP is performed immediately after LAMS placement, which is advantageous in urgent biliary obstruction but may carry a slightly higher risk of stent displacement if tract stability is suboptimal. In staged EDGE, ERCP is deferred for several days to allow partial tract maturation, potentially improving stability during duodenoscope passage. Multicenter data demonstrate overall technical success rates exceeding 95% with high rates of successful papillary cannulation and acceptable adverse event profiles (Figure 2)[30,31]. Persistent gastro-gastric fistulas can often be managed endoscopically after LAMS removal using techniques such as argon plasma coagulation to promote mucosal de-epithelialization, followed by defect closure with endoscopic suturing or an over-the-scope clip.
Figure 2 A 67-year-old female with a history of Roux-en-Y gastric bypass presented with abdominal pain attributed to chronic calcific pancreatitis, endoscopic ultrasound-directed transgastric endoscopic retrograde cholangiopancreatography was performed to facilitate endoscopic therapy.
A: Magnetic resonance imaging demonstrated a pancreatic duct stricture with upstream ductal dilation; B: Endoscopic ultrasound visualization of the excluded (remnant) stomach from the gastric pouch; C: The excluded stomach was distended under endosonographic guidance using a mixture of contrast and water; D: A 20-mm lumen-apposing metal stent was deployed to create a gastrogastric fistula; E: Endoscopic view confirming appropriate deployment of the proximal flange within the gastric pouch; F: A side-viewing duodenoscope was advanced through the stent into the remnant stomach to complete the endoscopic retrograde cholangiopancreatography.
Indications and outcomes
For patients with Roux-en-Y gastric bypass anatomy who require pancreaticobiliary intervention, EDGE has become an increasingly utilized means of obtaining therapeutic ERCP access. Its primary indication is the need for therapeutic ERCP in situations where conventional access to the native papilla is not feasible. Common clinical scenarios include choledocholithiasis (including cholangitis), malignant biliary obstruction, benign biliary strictures, bile leaks, and pancreatic duct disorders requiring intervention. In contrast to device-assisted enteroscopy ERCP (DA-ERCP), EDGE restores access to the remnant stomach and allows use of a standard duodenoscope and full complement of ERCP accessories, which is particularly advantageous for complex stone extraction, cholangioscopy, lithotripsy, or cases anticipated to require repeat interventions[28,31,32].
Comparative data increasingly support EDGE as a highly effective approach in this population. A recent network meta-analysis including 16 studies demonstrated that EDGE and laparoscopy-assisted ERCP (LA-ERCP) achieved significantly higher technical success than DA-ERCP, with no significant difference between EDGE and LA-ERCP for technical success. Importantly, EDGE was associated with shorter procedure time compared with both DA-ERCP (mean difference of 31 minutes) and LA-ERCP (mean difference of 78 minutes), while adverse event rates were comparable across approaches[33]. A separate systematic review directly comparing EDGE with LA-ERCP found no significant difference in technical success or adverse events, but EDGE reduced procedure duration by more than 90 minutes on average[34]. Across pooled analyses, technical success rates for EDGE are reported around 95%-96%, compared with 93% for LA-ERCP and 70% to 80% for DA-ERCP, with clinical success showing a similar distribution[33,34].
Despite its high efficacy, EDGE carries some risks. In a multicenter study including 172 patients undergoing EDGE, technical success was 99.4%, and overall clinical success of the intended ERCP was 95%. However, the main adverse event was stent dislodgement or migration occurring in 17% of patients[35]. The other concerns is a persistent gastrogastric fistula after the LAMS is removed. In the same registry, persistent fistula was noted in about 31% of cases. A case-control study demonstrated increased risk of persistent fistula in patients with longer stent placement time. A stent placed longer than 40 days increased the odds of persistent fistula by 4.5 fold, with the risk climbing for each additional week the stent stayed in[36]. While most of these fistulas can be closed endoscopically, it is important to ensure appropriate follow-up is arranged to remove the stent as soon as further access is not needed[37].
Further refinements of the technique have minimized these adverse events. A recent multicenter study of single-session EDGE using dedicated fixation strategies reported a high technical success rate at 95% without stent migrations suggesting that fixation may make urgent EDGE safer[38].
Approach selection
Choosing among EDGE, LA-ERCP, DA-ERCP, and percutaneous transhepatic cholangiography (PTC) drainage in Roux-en-Y gastric bypass patients comes down to four main factors: Urgency, complexity, local expertise, and patient-specific risks. EDGE shines when complex or repeated interventions are expected. Allowing access to the native papilla with a duodenoscope brings the ERCP armamentarium including cholangioscopy, repeated stent exchanges, pancreatic work; capabilities that cannot be matched with DA-ERCP approach. In urgent cases such as cholangitis, single-session EDGE allows rapid drainage without the need for surgical coordination. It is important to account for the delayed risk of persistent fistula when discussing options with patients. While endoscopic closure usually works, this possibility deserves further discussion with patients for whom metabolic consequences of a persistent fistula matter.
LA-ERCP remains a highly reliable alternative, particularly when EUS access to the remnant stomach is unsafe (interposed colon, significant ascites, inadequate luminal apposition) or when therapeutic EUS expertise is unavailable. Its technical success rates parallel those of EDGE, though it requires operative access and is associated with longer procedural time and greater resource utilization[33]. In centers with streamlined surgical-endoscopic coordination, LA-ERCP remains an appropriate and effective strategy.
DA-ERCP is ideal in straightforward cases where avoiding any transluminal fistula is a priority. The lower reported technical success relative to EDGE and LA-ERCP limits its role in complex situations. It should be considered in patients where balloon-assisted enteroscopy expertise is available, with limited advanced EUS or surgical backup.
In emergency settings such as severe cholangitis with unstable vital signs, or where immediate endoscopic access is not available, interventional radiology-guided PTC should be strongly considered. It provides effective biliary drainage and can serve as either a bridge or a definitive strategy in critically sick patients. While PTC avoids both transluminal fistula and surgical intervention, risks include catheter dislodgement, patient discomfort, and the need for staged internalization.
In summary, current evidence positions EDGE as the preferred approach in experienced centers because of its high technical success while enabling complex interventions. LA-ERCP is the reasonable alternative when EUS access is not feasible or in patients who need gallbladder surgery. DA-ERCP is reserved for certain cases with low-complexity in which further repeat ERCPs is not anticipated. PTC drainage is limited for patients who are too sick for the alternative strategies. The right choice for any individual patient is best worked out in a multidisciplinary framework that weighs urgency, complexity, local expertise, and patient-specific risks.
ALS: EUS-GIA AS INTERNAL DRAINAGE
Procedural considerations
In patients with prior pancreaticoduodenectomy or Roux-en-Y reconstruction and ALS, EUS guided drainage allows decompression of the obstructed limb via a transluminal bypass. ALS results from mechanical obstruction of the afferent limb leading to accumulation of biliopancreatic fluid potentially resulting in cholangitis, pancreatitis, vomiting, and abdominal pain[39,40]. EUS is used to locate the dilated afferent limb from the stomach. Once the dilated loop is visualized, access to the afferent limb is obtained either with a LAMS or by advancing a guidewire through a 19-gauge needle followed by LAMS deployment to bridge the afferent limb to the adjacent stomach. A 10 mm to 15 mm LAMS is typically used to allow effective decompression of the afferent limb. Successful drainage is often immediately apparent as enteric or bile-stained fluid flows through the stent into the receiving lumen, leading to symptomatic relief and radiographic decompression within days, without the need for external drains or formal surgical revision[40,41]. Several case series and multicenter experiences have corroborated the technical feasibility and symptomatic benefit of EUS-guided enteroenterostomy in ALS, even in patients with complex postoperative anatomy, with low reported complication rates in these selected cohorts[42,43].
Outcomes and complications
Although the evidence base for ALS remains smaller than for EUS-GE or EDGE, published series consistently suggest that EUS-guided internal drainage can achieve rapid decompression with acceptable adverse event rates in appropriately selected patients. The leading underlying disease associated with ALS is pancreatic cancer, which accounts for 67%-69% of cases[13,39,44]. EUS-guided drainage for ALS has demonstrated high technical and clinical success in published multicenter experiences and systematic reviews. In a multicenter study evaluating EUS-guided enteroenterostomy for ALS, technical success was achieved in 100% of cases, with clinical success in approximately 90% of patients, resulting in rapid symptom relief and effective decompression without the need for surgical revision[40].
Additional reviews of LAMS used for transluminal interventions in surgically altered anatomy including afferent loop obstruction showed high technical success rates above 90% and clinical success of 85%-95%[39]. Therefore, EUS-guided drainage appears to be the preferred modality for internal drainage of ALS compared to surgical and percutaneous approaches.
Adverse events are reported in 10%-20% of cases, with the main concerns being stent misdeployment, bleeding, and peritonitis. Misdeployment is usually related to inadequate distension of the afferent limb or technical factors. Most complications are able to be salvaged endoscopically while surgical rescue is rare. When compared to surgical revision, EUS-guided drainage allows a faster recovery with less morbidity while it eliminates the need for an external catheter and dislodgement risks that come with it when compared to percutaneous drainage. Long-term patency is good, although delayed obstruction or other stent-related events may lead to reintervention in a minority of patients[40,42,44]. In summary, the current evidence positions EUS-guided drainage as an effective safe minimally invasive alternative to surgery or percutaneous drainage for ALS, especially in patients at high surgical risk[13,39,44].
ADDITIONAL AND EMERGING APPLICATIONS
Outside the established roles in EUS-GE for GOO, EDGE, and internal decompression of ALS, EUS-GIA has been used in a number of other indications where conventional access is not possible and surgical options are limited or risky. Bilioenteric or pancreatoenteric strictures are a common issue in complex postsurgical anatomy, such as pancreaticoduodenectomy, especially when anastomosis is not reachable. In these settings, EUS-guided transluminal anastomosis using a LAMS can facilitate direct bypass or access to upstream segments, thereby enabling therapeutic interventions such as dilation or stenting across the stricture when direct luminal access fails. Although much of the historical literature on strictures has focused on balloon-assisted dilation or double-balloon enteroscopy techniques, the rationale for EUS-guided access in this context derives from its ability to create a controlled fistulous tract under real-time imaging in conditions where luminal scope passage is not possible. In a cohort of 216 patients undergoing various EUS-guided anastomoses, approximately 20% of cases were performed specifically to facilitate endoscopic access to a bilioenteric anastomosis for therapeutic intervention, such as balloon dilation of strictures or management of intrahepatic stones. Additionally, EUS-guided creation of jejunojejunostomy or gastrogastrostomy has been described to allow access to excluded segments of bowel for complex ERCP or other endoscopic interventions in patients with non-gastric bypass Roux-en-Y anatomy, essentially extending the principles of EDGE to broader surgical reconstructions[6,45].
Another emerging application involves jejunojejunostomy or enterocolostomy bypass for small bowel obstruction in select benign or malignant scenarios beyond the duodenum. Small series have described effective EUS-guided creation of an internal bypass between the dilated proximal bowel and a segment downstream to the obstruction, mostly in patients for whom surgery is prohibitive or impractical (Figure 3)[46-48].
Figure 3 A 62-year-old female with metastatic colon cancer presented with distal small bowel obstruction secondary to peritoneal adhesions.
Endoscopic ultrasound-guided enterocolostomy was performed for palliative decompression. A: Contrast-enhanced computed tomography demonstrated diffuse small bowel dilation consistent with distal obstruction; B: Endosonographic visualization of the dilated small bowel loop from the descending colon; C: The target small bowel was accessed using a 19-gauge needle and further distended under endoscopic ultrasound guidance with a mixture of contrast and water; D: A 15-mm lumen-apposing metal stent (LAMS) was deployed to create an enterocolonic fistula; E: Endoscopic view confirming appropriate stent expansion and positioning; F: A double-pigtail plastic stent was placed through the LAMS to maintain patency and reduce the risk of stent occlusion or migration.
While most of these emerging applications have limited evidence and rely mainly on small case series or expert opinion, the trajectory of the literature is clear: EUS-GIA is finding additional uses in a growing list of complex GI settings where traditional approaches fall short. As more evidence becomes available and the technique further matures, indications for EUS-GIA will likely continue to expand.
FUTURE DIRECTIONS AND KNOWLEDGE GAPS
The future of EUS-GIA relies on determining which patients and indications would benefit most out of each application. The priority would be establishing patient-selection criteria and procedural protocols to decrease the risk of adverse events. Multicenter series have reported high technical and clinical success rates across indications, but outcome definitions have been inconsistent limiting comparisons between studies. Well-defined prospective registries with standardized reporting on technical success, clinical success, reintervention rates, and long-term patency would address that. Further device refinements are also important. Better LAMS design with features that reduce leak and migration along with better scope optics should make complex transluminal drainage easier and safer over time.
Randomized comparative studies between the different modalities are essential in advancing EUS-GIA forward. A randomized trial favored EUS-GE over enteral stenting for GOO regarding reintervention and stent patency[27]. Another randomized controlled trial showed EUS-GE matched surgical gastroenterostomy on clinical success while leading to faster recovery and fewer adverse events[25]. However, similar randomized trials are lacking for EDGE vs LA-ERCP, and for EUS-guided drainage of ALS against surgical revision. Existing meta-analysis reported similar technical success rates for EDGE compared to LA-ERCP while showing a shorter procedure time for EDGE[34]. However, prospective randomized trials that capture cost, recovery time, and quality of life are still needed to drive clinical decision-making. Long-term outcomes are also necessary. Studies have demonstrated that longer LAMS dwell time leads to a higher risk of persistent fistula after EDGE procedure[17,36]. Standardized surveillance protocols following completion of EDGE and evidence-based closure techniques would help address this complication. Finally, it is important to recognize that structured training pathways and competency benchmarks are essential to spread this technique safely beyond high-volume tertiary centers. Reasonable competency benchmarks would include completion of a dedicated advanced endoscopy fellowship with LAMS exposure; 20-25 proctored cases before independent practice; technical success of ≥ 90% with adverse event rates within published norms; and institutional infrastructure for multidisciplinary review and surgical rescue. Simulation-based training, procedural registries, and EUS-GIA-specific metrics built into GI society quality frameworks would support a safe adoption pathway[49-51].
CONCLUSION
What started as a novel transluminal idea has become a versatile therapeutic platform for complex obstructive and access problems in GI and pancreaticobiliary disease. Current data on the major indications including GOO, altered anatomy requiring ERCP, ALS, and selected distal small bowel obstructions show high technical and clinical success with acceptable safety. When compared to surgical and endoscopic alternatives, EUS-GIA has comparable high efficacy while decreasing morbidity and procedural time. As devices continue to improve and randomized comparative trials become available, EUS-GIA is poised to become an important component of multidisciplinary management discussions. Continued emphasis on prospective studies, procedural standardization, and long-term outcome evaluation will determine its definitive role and help define best practices for patient selection, technique optimization, and complication management.
Peer review: Externally peer reviewed.
Peer-review model: Single blind
Specialty type: Gastroenterology and hepatology
Country of origin: United States
Peer-review report’s classification
Scientific quality: Grade B, Grade B, Grade B, Grade C
Novelty: Grade B, Grade B, Grade B, Grade C
Creativity or innovation: Grade B, Grade B, Grade B, Grade C
Scientific significance: Grade B, Grade B, Grade C, Grade C
P-Reviewer: Kitamura K, Director, MD, PhD, Professor, Japan; Tan J, China; Wen Y, Associate Chief Physician, PhD, China S-Editor: Fan M L-Editor: A P-Editor: Zhao S
