Malfunction of the metallic stent can be caused by encrustation of crystals, bacterial sludge, bile salts, and tumor compression or tumor ingrowth.

• 金属支架的功能障碍可以由胆管内的结晶凝块，细菌性污泥，胆盐，及肿瘤压迫或肿瘤直接侵入支架。