Figure 1 Guidance by ultrasound and digital subtraction angiography. A: The dilated bile duct was punctured with an 18G cannula puncture needle; B: A guide wire was introduced through the puncture needle sheath; C: Two guide wires were introduced through the 8F catheter; D: One guide wire was introduced into the stent conveyor, and the other into the 8F catheter, ready to push the iodine-125 (¹²⁵I) seed strands; E: Successful placement of stent and ¹²⁵I seed strands; F: External drainage tube angiography showing the unobstructed stent; G: ¹²⁵I seeds were placed into 4F plastic tubes to make ¹²⁵I seed strands.