EUS-specific stents: Available designs and probable lacunae.

Abstract

Interventional EUS has seen exponential growth in its indications and applications in the last decade.[1,2,3] Dedicated endoscopic devices for EUS-guided interventions are still limited. Up until recently, the tools used have been borrowed from other procedures such as ERCP. In interventional EUS, the linear-array echoendoscope allows a needle to be advanced under EUS-guidance from the upper gastrointestinal lumen to the biliary, pancreatic, or another adjacent intestinal lumen. Real-time puncture can be performed and provide the possibility of EUS-guided transluminal drainage (EUS-TLD). Plastic stents and conventional self-expandable metallic stents (SEMSs) were initially used but present several limitations due to their design.[1,4,5] They lack lumen-to-lumen anchorage and present migratory risks in the absence of stricture to hold them in place. Plastic stents are associated with potential pneumoperitoneum and bile peritonitis, whereas fully-covered SEMS (FCSEMS), despite preventing bile leak, will not maintain secure apposition between two nonadherent organs. Furthermore, their length often exceeds the anatomical requirement of a shorter transluminal anastomosis and predisposes them to obstruction as well as difficult positioning. With the rise in new EUS-guided interventional techniques, new tools, in particular, new stent designs have evolved to facilitate the various applications. A few EUS-specific stents have now become available for EUS-TLD.[4,5] We hereby review the stent designs and discuss lacunae to be addressed to improve the efficacy, safety, and ease of procedures.