Angle of covered self-expandable metallic stents after placement is a risk factor for recurrent biliary obstruction

Figure 1 Measurement of the angle of covered self-expandable metallic stents after placement on abdominal radiograph. A: Covered self-expandable metallic stent (CSEMS) after placement; B: Measurement of the obtuse angle of CSEMS after the placement. 1: The lines extending from the proximal point to the narrowest point; 2: The lines extending from the distal point to the narrowest point. The obtuse angle of CSEMS after the placement between line 1 and line 2 was 132°. CSEMS: Covered self-expandable metallic stent.

Figure 2 Diagram of study design. SEMS: Self-expandable metallic stents; ERCP: Endoscopic retrograde cholangiopancreatography; CSEMS: Covered self-expandable metallic stents; UCSEMS: Uncovered self-expandable metallic stents; MBO: Malignant biliary obstruction; RBO: Recurrent biliary obstruction.

Figure 3 Long-term results of covered self-expandable metallic stents in unresectable distal malignant biliary obstruction. A: Non-recurrent biliary obstruction (RBO) rate and median time to recurrent biliary obstruction (TRBO); B: Overall survival rate; C: Comparison of TRBO in the < 130° group and ≤ 130°group. RBO: Recurrent biliary obstruction; TRBO: Time to recurrent biliary obstruction; NA: Not available; CSEMS: Covered self-expandable metallic stents; MBO: Malignant biliary obstruction; CI: Confidence interval

Figure 4 Evaluation of accuracy by receiver operating characteristic curve analysis. AUC: Area under the curve; ROC: Receiver operating characteristic; CI: Confidence interval.

Figure 5 Evaluation of consistency for the angle of covered self-expandable metallic stents after placement. CSEMS: Covered self-expandable metallic stents; CI: Confidence interval.