Predictors of the technical success of ultrasound-guided percutaneous transhepatic biliary drainage for biliary obstruction

Figure 1 Flowchart of patient enrollment and procedural outcomes. Diagram illustrates the pathway of 263 patients undergoing initial ultrasound-guided percutaneous transhepatic biliary drainage through sequential attempts. Boxes indicate the number of procedures at each attempt stage (first, second, and third/subsequent) and their immediate outcomes (success or failure). The cumulative technical success rate after all attempts was 94.3% (248/263).