Gastrointestinal Radiology > Procedures > Metal Stents > Metal Stents (3)


Self-Expanding Metal Stents for Treatment of Esophageal Strictures and Esophagorespiratory Fistulas

Technique

  1. The methods of delivery are similar for all self-expanding metal stents that are placed using fluoroscopic guidance.  Deployment of the Ultraflex™ Esophageal Stent will be described in detail.  After removal of the deflated balloon catheter from the esophagus, the delivery system containing the stent is advanced over the guidewire into the stricture (Fig. 1A).

A. B. C. D.

Fig. 1.  Illustration of steps in placement of Ultraflex™ Esophageal Stent.  See text for description.

The delivery system is relatively rigid, and extension of the patient’s neck will make advancement easier.  The position of delivery system is adjusted until its inner-most pair of radiopaque markers are symmetrically placed at least 2-3 cm beyond the proximal and distal margins of the mass.  These markers indicate the final position of the ends of the stent when it is fully expanded.  The safety sleeve should not be removed from the proximal shaft of the delivery catheter until the stent system is in proper position.  The safety sleeve prevents inadvertent retraction of the outer sheath, which will allow moisture to enter and initiate premature gelatin dissolution and stent expansion, prior to proper positioning of the stent.

  1. When the radiopaque markers on the shaft of the delivery catheter are properly aligned with the esophageal tumor, the outer sheath is withdrawn in one continuous motion (Fig. 1B).  

  2. Upon exposure to esophageal moisture, the gelatin around the stent should completely dissolve and permit the stent to expand within 5 to 10 minutes (Fig. 1C).  If the stent does not expand within 10 minutes, a small amount of water may be instilled into the esophagus through a second catheter to accelerate stent expansion.  To prevent aspiration, the procedure table should be tilted with head up 30° to 45°.

After release and expansion of the stent are confirmed fluoroscopically, the delivery system is carefully removed, leaving the guidewire and stent in place.  The stent must be completely released from the inner catheter; otherwise, removal of the delivery system may dislodge the stent.

  1. A 12-mm or 15-mm balloon catheter is then passed over the guidewire and inflated to distend and attach the stent more firmly to the esophageal wall (Fig. 4D).  Careful insertion and removal of the deflated balloon with fluoroscopic guidance is recommended to avoid inadvertent stent displacement.

The guidewire is removed, and the patient is monitored until the effects of the topical anesthetic and I.V. conscious sedation have disappeared.  Then, barium esophagography is performed to evaluate baseline stent patency and position–and to rule out significant iatrogenic injury to the esophagus.  If the procedure is done in an outpatient setting, the patient may be discharged after an uneventful 4-hour period of close observation.

 


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