New “knitted” EGIS esophageal stent allows atraumatic inside-out removal by inversion
05 July 2013 (online)
Modern esophageal stents can be extracted by capture of a purse string. Under traction, braided stents lengthen and narrow. However, strictures are often friable, and extraction can cause hemorrhage or perforation.
A new nitinol stent (EGIS; S&G Biotech, Seoul, Korea) consists of a “knitted” construction of interlinked wires, as used in enteral stents. Unlike in braided stents, no straightening forces exist within the skeleton, resulting in a resistance-free three-dimensional conformation ([Fig. 1]) and reduced stent shortening on release compared with braided stents. Stent segments may move against each other, and the distal end can be inverted into the trunk by traction on the lower purse string. The stent peels away from the esophagus, reducing shearing forces on the surrounding tissues.
We present two cases of stent removal in this novel fashion.
Case 1: A 61-year-old man with a benign post-radiation stricture had suffered a perforation into the left main bronchus after balloon dilation during insertion of a biodegradable stent. The fistula was successfully occluded with an 18-mm, 9-cm EGIS esophageal stent. Bronchoscopy suggested healing, and stent removal was attempted under conscious sedation. Using rat-toothed forceps, the distal retrieval string was captured ([Fig. 2]) and the distal end of the stent inverted segment by segment, resulting in a sensation of falling dominoes. Removal was easy and atraumatic, but unfortunately the fistula remained.
Case 2: A 69-year-old woman with a dilation-resistant post-radiation stricture had a biodegradable stent inserted. This did not expand adequately, resulting in episodes of food impaction. An 18-mm, 13-cm EGIS anti-reflux stent was placed coaxially, resulting in complete expansion of the biodegradable stent. The anti-reflux stent was removed by inversion 20 days later ([Fig. 3], [Video 1]), leaving the fully expanded biodegradable stent in situ, with resulting grade-1 dysphagia.
Interventionists must be aware of continued developments in stents, in order to offer patients the most appropriate option.