Distally Migrated and Impacted Biliary Metallic Stents: Removal versus Trimming

We read with interest the article by Shaver et al. [1] on a case of impaction of a biliary self-expanding metallic stent (SEMS) in the duodenal wall opposite to the papilla. The stent was trimmed using a neodymium-yttrium-aluminum-garnet (Nd:YAG) laser until about 1 cm of stent protruded from the papillary orifice. Because the stent was occluded by biliary debris, the shortened stent was then cleared with balloon sweeping. We believe that endoscopic trimming and mechanical cleaning of the stent was an inadequate management. Moreover, such trimming requires a Nd:YAG laser which is not available in all hospitals, and might need considerable time. After trimming, unraveled stent wires might escape from the duodenum to the jejunum.

We suspect that this migrated SEMS was a covered stent because the migration occurred at 1 year following initial stent placement. Covered SEMSs penetrate less deeply into the biliary wall compared with uncovered stents [2] [3], and may have a higher incidence of migration [3] [4] [5]. We have reported an open-biopsy-forceps technique for successful endoscopic removal of such covered SEMSs [6]. A closed biopsy forceps was advanced through the stent mesh, and opened within the stent, forming an ”anchor” inside the stent. With endoscope withdrawal, the stent was easily dislodged from the duodenum to the stomach. After snaring of the stent end, the stent was removed by complete endoscope withdrawal. The technique itself required a mean time of 10.2 minutes.

Even if the SEMS described by Shaver et al. was an uncovered stent that could not be removed even surgically [7] [8], such a stent could have a higher incidence of occlusion after mechanical cleaning. A retrospective review of occluded SEMSs [9] demonstrated that the occlusion was best managed by endoscopic placement of a second SEMS or a plastic stent, and that mechanical cleaning was ineffective. The open-biopsy-forceps technique is a simple, rapid, and effective method that does not require special equipment. We therefore believe that, for distally migrated and impacted biliary SEMSs, our technique is superior to the trimming.

References

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