How do woven Elgiloy and nitinol self expandable stents differ?
Woven stents, such as the Wallstent, have several unique characteristics. They are very radiopaque and can be easily seen on fluoroscopy, even in obese patients. The stents are reconstrainable, meaning that they can be almost entirely deployed, recaptured, moved, and then redeployed in a different location. The tradeoff, however, is that the length of the stent depends on its fully expanded diameter. These stents may shorten significantly as they expand over time, uncovering a region of pathology. Alternatively, if the stent does not expand to the degree expected, the stent may remain too long. Woven stents are available in large sizes (up to 24 mm in diameter) and are often used to create transjugular intrahepatic portosystemic shunts (TIPS) or to stent large central veins.
Laser-cut self-expandable stents are not reconstrainable. Because the stents are constructed of rings linked together, they are subject to significant foreshortening and remain at a relatively stable length regardless of diameter. Nitinol is less radiopaque then Elgiloy, and these stents may be difficult to see, especially in obese patients.