Self-Expandable Metal Stents in GI Endoscopy: Esophageal, Duodenal and Colonic Options

Beyond the biliary tree, self-expandable metal stents are a first-line tool for managing malignant obstruction — and increasingly benign strictures, leaks and fistulas — right through the GI tract, from the esophagus to the colon. The design priorities shift by location, but the underlying construction logic stays consistent.

Esophageal Stents

The esophageal range spans routine malignant dysphagia through to complex post-surgical leaks:

• S Esophageal Stent — the baseline design: braided, silicone-covered, with enlarged head ends (8mm larger than the trunk) to resist migration.
• DUAL™ — a softer, lower-radial-force variant aimed at reducing insertion pain while still resisting foreshortening.
• DOUBLE™ and DOUBLE™ (Anti-reflux) — double-layered, combining a covered inner layer against tumor ingrowth with an uncovered outer mesh against migration. The anti-reflux variant adds a PTFE skirt for placement across the EG junction.
• CERIVICAL™ and CONIO™ — shortened proximal-head designs for strictures near the upper esophageal sphincter, minimizing risk to the vocal cords; CONIO is sized specifically for hypopharyngeal strictures.
• MEGA™ and BETA™ — the two designed around surgical leaks rather than malignant strictures. MEGA is an extra-long, large-diameter design for post-sleeve-gastrectomy leaks spanning into the duodenum; BETA is double-layered with retrieval strings at both ends for bariatric leaks and fistulas in tortuous anatomy.

Delivery format is a separate axis of choice: proximal-release systems are generally preferred for upper strictures (positioning relative to the proximal tumor margin matters more), while Through-The-Scope (TTS) systems suit tight or tortuous anatomy where endoscopic control during deployment is the priority.

Duodenal (Pyloric) and Colonic Stents

Malignant gastric outlet obstruction and colorectal obstruction share a similar decision structure to biliary disease:

• Uncovered, weaving-construction stents (D Pyloric/Duodenal, D Enteral Colonic) maximize conformability in tortuous anatomy while keeping migration and perforation risk low — the standard choice where tumor in-growth anchoring the stent isn’t a concern.
• Covered, braided stents (S Pyloric/Duodenal, S Enteral Colonic) add tissue-ingrowth resistance and are available in TTS or OTW delivery, useful for benign strictures or where anastomotic/fistula repair is part of the picture.
• COMVI™ variants extend the triple-layer PTFE-and-mesh approach used in the biliary range to both duodenal and colonic anatomy, and the Flare configuration adds an uncovered proximal flare with a reinforced large-cell body for cases where migration risk is higher and larger diameters (up to 26mm) are needed.

What Determines the Right Choice

Across all three locations, the same variables keep coming up: benign vs. malignant, anatomy tortuosity, migration risk, and whether TTS or OTW delivery fits the procedural setup. Diameter and length ranges are broad across the range (16–30mm diameter depending on location, 6–23cm length), so sizing is rarely the limiting factor — construction and covering choice usually is.

This is a general overview based on manufacturer product literature, not clinical guidance. Device selection should always be made by the treating clinician based on the specific case.