Cut Clean, No Recurrence? The Hidden Secrets of Snares That 90% of Doctors Overlook

Cut Clean, No Recurrence? The Hidden Secrets of Snares That 90% of Doctors Overlook

— “Surgical success depends not only on the incision, but also on the material science behind the instruments.”

Colorectal polypectomy is one of the most common procedures in gastrointestinal endoscopy. Data show that nearly 90% of colorectal cancers originate from adenomatous polyps. Ensuring polyps are removed safely and completely is therefore critical—and the snare plays the key role.

 Snare: The Cutting Tool in Endoscopy

A snare is a metal wire loop delivered through the working channel of an endoscope. By tightening the handle, the physician closes the loop around the polyp base, cuts it off, and retrieves the specimen. It is not only the final step in EMR/ESD procedures, but also the decisive factor for complete resection and bleeding control.

Common Snare Shapes

What Is a Tie-layer?

A Tie-layer is essentially a functional intermediate layer.It bonds to the etched PTFE surface while also being compatible with the outer polymer layers, thus serving as a “bridging adhesive layer.”In other words, the Tie-layer is the key to ensuring that “modified PTFE” maintains a long-lasting and stable connection with a variety of outer materials.

Additional Roles of the Tie-layer in PTFE Etched Tubes

① Enhanced Bonding Strength
Although etching increases PTFE surface activity, there can still be risks of local delamination when bonded with outer materials. A Tie-layer further strengthens the adhesion, ensuring stable catheter structures during use.

② Resistance to Environmental Aging
Etching reduces PTFE’s natural inertness, making it more vulnerable to environmental factors like humidity and temperature. The Tie-layer acts as a protective barrier for the etched surface, extending the durability of the composite structure.

③ Improved Process Compatibility
With the Tie-layer, etched PTFE can bond more easily with materials such as PA, Pebax, or braided metal layers, widening the processing window and offering greater design flexibility.

More Than Just a Bonding Layer

The Tie-layer is not just an “adhesive layer”—it is the key enabler that allows PTFE etched tubes to achieve high-performance composite structures.

Oval: The most common type, for typical polyps

Round: Suitable for large, flat polyps

Hexagonal: Provides stronger grip, useful for flat lesions

Crescent: Designed for polyps in challenging positions

In practice, round and oval snares can effectively manage the majority of gastrointestinal polyps.

 Cold Snare vs. Hot Snare: Same Cut, Different Logic

 The “Inner Strength” of Snares: Wire Material and Braiding

The core of the snare is made of steel wire, which allows for conductivity and provides strong tension, enabling better “strangulation and resection” effects. Additionally, for snares used with electricity, the larger the contact area, the better and more stable the cutting effect. To achieve an “anti-sliding” effect, the steel wire of the snare is braided in a spiral pattern, much like a "little girl’s braid". This design increases the contact area between the snare and the polyp, while also preventing the polyp from slipping out.

 The Real Key: Not Cold vs. Hot, but Materials

Many assume the difference between cold and hot snares is simply whether electricity is applied. In fact, catheter materials are the fundamental distinction.

Hot Snare Catheters: Heat Resistance + Electrical Insulation

l Materials: PTFE, PEEK

l Reason: Must withstand high temperatures, prevent carbonization, ensure high insulation, and maintain smooth device delivery

l Advantage: Minimizes electrical leakage risk, improves procedural safety

Cold Snare Catheters: Flexibility + Cost Advantage

l Material: HDPE

l Reason: No need to endure high temperatures, emphasis on flexibility, control, and low friction

l Advantage: Lightweight, cost-efficient, optimized for quick resections

 In short: Hot snares rely on advanced insulation materials for safety, while cold snares emphasize lightweight, flexible materials for efficiency.

A snare may seem like just the “final step,” but in reality it is a product of surgical technique and material science. Whether it is HDPE, PTFE, or PEEK, ECO has extensive manufacturing experience, providing mature solutions for diverse clinical needs.

As a professional CDMO factory

If you’d like to learn more about Tie-layer application solutions or request technical support, please contact the ECO Team.

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