Motorized spiral enteroscopy in altered anatomy: Balancing clinical success with safety challenges

Abstract

Performing endoscopic retrograde cholangiopancreatography (ERCP) in patients with Roux-en-Y-anatomy is technically challenging and additional techniques including balloon-assisted enteroscopy, endoscopic ultrasound (EUS) guided, and percutaneous approaches offers only modest success rates. Motorized spiral enteroscopy (MSE)-assisted ERCP (MSE-ERCP) has emerged as a potential alternative. In a retrospective study by Nennstiel et al, MSE-ERCP achieved high success rates for biliary entry (88%) and therapeutic intervention (83%). However, outcomes varied significantly between bilioenteric anastomosis (93%) and native papilla (63%), underscoring the importance of anatomy-driven procedural selection. Despite encouraging efficacy, the global withdrawal of the MSE platform due to serious device-related complications highlights the ongoing balance between feasibility and safety. Future directions should prioritize refinements in device engineering, multicenter prospective trials comparing MSE with balloon-assisted and EUS-guided techniques, and systematic outcome stratification by anatomical subgroup. Such efforts will be critical to defining the role of MSE within the therapeutic algorithm for surgically altered anatomy.

Key Words: Gastric bypass; Ampulla of Vater; Roux-en-Y anastomosis; Balloon enteroscopy; Cholangiopancreatography

Core Tip: Endoscopic retrograde cholangiopancreatography in Roux-en-Y anatomy remains technically challenging, with higher success through bilioenteric anastomosis than the native papilla. Emerging strategies including balloon-assisted enteroscopy, motorized spiral enteroscopy (MSE) and endoscopic ultrasound-guided drainage highlight the need for personalized procedural selection based on anatomy, clinical scenario, and institutional expertise. MSE offers high diagnostic and therapeutic potential but requires further refinement to address safety concerns before wider adoption.

TO THE EDITOR

Endoscopic retrograde cholangiopancreatography (ERCP) is an advance endoscopic procedure that at time become challenging in patients with altered anatomy. Roux-en-Y is a type of surgically altered gastrointestinal (GI) anatomy created during certain operations, such as, Roux-en-Y gastric bypass (RYGB) for obesity treatment, Roux-en-Y hepaticojejunostomy (biliary diversion after liver transplant, bile duct injury, or choledochal cyst surgery), or Roux-en-Y reconstruction after gastrectomy (e.g., gastric cancers and ulcer disease)[1,2]. The higher success rate of > 90% has been reported for the ERCP in Roux-en-Y-anatomy performed through a bilioenteric anastomosis (hepaticojejunostomy), as the anastomotic site is larger and more accessible than the native papilla. In contrast, procedures targeting the native papilla remain technically challenging, with consistently lower success rates (approximately 60%-70%)[3,4]. Schematic comparison between native papilla and bilioenteric anastomosis in Roux-en-Y anatomy is clearly depicted in Figure 1.

Figure 1 Schematic comparison of two common Roux-en-Y configurations relevant to endoscopic retrograde cholangiopancreatography. The left panel shows a long alimentary (Roux) limb with access to the native papilla. The right panel depicts a short Roux limb after hepaticojejunostomy.

To overcome these challenges, several advanced techniques have been developed, including double-balloon enteroscopy (DBE) and single-balloon enteroscopy, motorized spiral enteroscopy (MSE), and endoscopic ultrasound (EUS) – guided approaches such as EUS-directed transgastric ERCP (EDGE), each offering distinct advantages and limitations in terms of procedure complexity, success rates, and safety. Table 1 summarizes the differences between these latter techniques[5-7].

Table 1 Differences between double-balloon enteroscopy and single-balloon enteroscopy, motorized spiral enteroscopy, and endoscopic ultrasound-directed transgastric endoscopic retrograde cholangiopancreatography.

Ref.	Feature	Technique	Procedure time	Technical success (enteroscopy)	Complications rate
Koh et al[6]	DBE	Two balloons (scope + over tube) alternate inflation for bowel anchoring and advancement	Longer total procedure time, especially in deep insertion cases	High (approximately 93%-95%)	Low (approximately 1%-4%), primarily minor mucosal tears or bleeding
Koh et al[6]	Single-balloon enteroscopy	One balloon on over tube inflates for fixation: Scope tip manual anchoring	Slightly shorter than DBE	High (approximately 90%-98%)	Low, similar to DBE
Mussetto et al[5]	Motorized spiral enteroscopy	Motorized rotating spiral over tube pleats small bowel for advancement	Generally shortest procedure time due to motorized advancement	Comparable (approximately 88%-95%)	Higher; reported esophageal mucosal injuries, withdrawals, and rare serious adverse events led to market withdrawal
Kedia et al[7]	EUS-directed transgastric endoscopic retrograde cholangiopancreatography	EUS-guided puncture and drainage or stent placement for biliary access	Variable; can be shorter but depends on approach complexity	Indirect (not an enteroscopy technique; access success varies)	Moderate; risks include bile leak, perforation, pancreatitis

DBE: Double-balloon enteroscopy; EUS: Endoscopic ultrasound.

PERSONALIZED PROCEDURAL SELECTION

Future advancements in ERCP for patients with Roux-en-Y anatomy must move beyond a one-size-fits-all algorithm and embrace a paradigm of personalized procedural selection. This strategy is endorsed by American Society of Gastrointestinal Endoscopy guidelines that suggests EDGE over laparoscopic-assisted or enteroscopy-assisted ERCP (E-ERCP) in RYGB patients needing biliary drainage, given its superior technical and clinical success, shorter procedure times, and cost-effectiveness, while laparoscopy-assisted ERCP (LA-ERCP) may be preferred if concomitant surgery is planned in patients with intact gallbladder. For non-gastric bypass altered anatomies (e.g., hepaticojejunostomy, Whipple, Billroth II), E-ERCP remains the first-line approach, with EUS-guided biliary drainage or percutaneous transhepatic biliary drainage reserved for failed cases[8]. Another important consideration for E-ERCP is the length of alimentary limb, as procedures become difficult if length is more than 150 cm; beyond this, LA-ERCP or E-ERCP may be safer options in urgent settings and in benign disease, given that single-session EDGE has been associated with lumen-apposing metal stent-related complications, although the use of a suturing device may enhance its safety[9-11]. Thus, choice of technique should be individualized based on patient anatomy, clinical scenario, and local expertise. These mandates tailoring the approach to the individual's specific anatomical configuration.

MSE: PROMISE, PITFALLS, AND THE PATH FORWARD

MSE was designed to overcome the primary challenges of deep enteroscopy: (1) Procedure time; (2) Depth of insertion; and (3) Technical complexity. Despite its promising advantages most significant concern with MSE is the potential for mucosal trauma and serious complications, namely perforation[5]. One multicenter prospective study by Al-Toma et al[12] demonstrated high diagnostic yield (64%), therapeutic utility (54%), and the ability to achieve panenteroscopy in 70% of cases by MSE even in surgically altered GI anatomy with relatively short procedure times and only minor adverse events reported. Another systematic review and meta-analysis demonstrated technical success of 94%-100% but also highlighted a non-negligible adverse effect rate (11%-20% minor; up to 1% major, including perforation, pancreatitis, and bleeding) related to therapeutic intervention not to spiralling technique[13]. In contrary, Chan et al[14] demonstrated comparable technical, diagnostic, and therapeutic success to DBE, but was associated with a higher frequency of adverse events, including esophageal lacerations and ileal perforation, reflecting limitations of current device design. Future device refinements should focus on safer delivery systems, such as retractable spiral fins, to facilitate atraumatic transit and emergency withdrawal when needed[5]. The niche for MSE, if safety concerns can be addressed, may lie in its ability to respect native anatomy and utilize standard ERCP accessories.

CONCLUSION

Optimal biliary access in Roux-en-Y anatomy requires a personalized procedural strategy that integrates anatomical configuration, clinical indication, patient comorbidities, and local expertise. A tailored, evidence-based approach remains essential to maximize technical success and safety in this challenging patient population as after all patients’ safety with best possible care is pivotal in clinical practice.