Hydrophobin-Beschichtung zur Okklusionsprävention biliärer Plastikstents – erste Ergebnisse

Fragestellung:

Stent occlusion is a major complication in biliary stenting. This porcine study tested a newly developed coated biliary stent with a dedicated new surface proteine (hydrophobin) alone or with hydrophobin and heparin for preventing stent occlusion.

Methodik:

The stents were placed in into 15 healthy pigs (5 uncoated stents, 5 stents coated with hydrophobin and 5 stents coated with hydrophobin and heparin). After 3 weeks the success rate was evaluated by necropsy and macroscopic and microscopic evaluation (including electron microscopy) of the stents as well as of the bile ducts. The following items were evaluated: accuracy and ease of delivery and deployment, stent function and patency, inflammatory changes of the common bile duct and weight increase of the pigs.

Ergebnisse:

The technical success rate for stent implantation was 93%. In 3 cases the stent was still in situ after 3 weeks, in the other 12 cases the stent has been migrated spontaneously.. The stent patency of non-migrated stents (2 stents coated with hydrophobin and heparin, one with hydrophobin alone) was 100%. After microscopic evaluation, the CBD-wall was thicker in the cases with stents in situ in comparison with the CBD-wall in the pigs with lost stents. Heparin and hydrophobin coated stents lead to a higher inflammatory reaction and an increased CBD-wall-thickening in comparison with uncoated stents.

Schlussfolgerung:

Implantation and patency of hydrophobin-coated biliary stents was successful and effective. Caused by the hydrophobin coating the stent patency was high but at the expense of a high migration rate. Further studies have to be performed e.g. with pigtail-endoprosthesis to verify the benefit of these hydrophobin coated stents.