Preferable timing of intraductal ultrasonography during endoscopic retrograde cholangiopancreatography lithotomy: A prospective cohort study

Abstract

Aim: Intraductal ultrasonography (IDUS) is a highly sensitive and non-invasive detective method that can be used to detect complete calculus clearance during endoscopic retrograde cholangiopancreatography (ERCP). In this study, we examined the preferable timing of IDUS during ERCP lithotomy.

Methods: From 2017 to 2020, patients with choledocholithiasis were randomized into IDUS-BL (IDUS performed before lithotomy) group, IDUS-ALC (cholangiography and IDUS performed after lithotomy) group, and IDUS-AL group (IDUS performed after lithotomy) group. The influence of IDUS on the accuracy of prejudgment, the incidence of residual stones, the need for repeated lithotomy (RL), and fluoroscopy time were analyzed.

Results: A total of 184 patients were enrolled. No residual stones were found during follow-up in any of the three groups. There was no difference in prejudgment accuracy rate on size and number of stones between different groups (all P > 0.05). RL were performed in 5, 9, and 9 cases of IDUS-BL, IDUS-ALC, and IDUS-AL group, respectively (P > 0.05). IDUS-AL group had a shorter fluoroscopy time than the other two groups (1.5 ± 0.6 vs. 2.8 ± 1.2, 2.5 ± 1.0 min, P < 0.05). Incidence of RL was related to the location of calculus [middle or lower part of common bile duct (CBD)], lithotripsy, dilated CBD (2.12 ± 0.46 vs. 1.78 ± 0.40 cm, P < 0.01), and inaccuracy prejudgment.

Conclusion: IDUS performed after lithotomy is preferable for shorten fluoroscopy time during ERCP. IDUS is a reliable solution for the stone omission, which may be more valuable for patients with high-risk factors of RL.

Keywords: common bile duct (CBD); endoscopic retrograde cholangiopancreatography; intraductal ultrasonography; lithotomy; stone.

FIGURE 1

Consort flow diagram of patients undergoing ERCP and IDUS.

FIGURE 2

Cholangiographic, IDUS, and endoscopic images from typical cases. Patient 1: A 37-year-old male choledocholithiasis patient was diagnosed with abdominal ultrasonography. (A) The cholangiographic image failed to reveal the stones. (B) IDUS confirmed the presence of stones in the bile duct, but the number of stones was not accurate. (C) During lithotomy, a large amount of sludge was pulled out. Since more than three extractions were done, the score of stones was modified as score 3. Patient 2: A 65-year-old female patient diagnosed with choledocholithiasis by abdominal CT scan. (D) Only one stone was found under the shaft of the endoscope, while stones inside the end of the common bile duct could not be seen. (E) More than five brownstones were extracted, and most of them existed in the lower part of the common bile duct. Patient 3: A 75-year-old male choledocholithiasis patient was diagnosed with abdominal ultrasonography. (F) Cholangiography demonstrated many stones in the middle part of the common bile duct, and stones in the cystic duct can also be seen. (G) Black calculus with different sizes was taken out. Patient 4: A 68-year-old male patient was diagnosed with choledocholithiasis by abdominal CT scan. (H) Stones <1 cm were shown above the shaft by cholangiography. (I) The long diameter of the stone was around 1.2 cm.

FIGURE 3

Ultrasonographic and endoscopic images from typical cases. Patient 1: (A) IDUS showed flocculent echo in the lumen; (B) the thick bile was the cause of acoustic characteristics. Patient 2: (C) A little arc high-echo with a shadow was found by IDUS, and it was distinguished from the guidewire, which has ripples in the rear; (D) a small stone with a diameter around 3 mm in size was pulled out. Patient 3: (E) Flocculent echo was detected inside the bile duct, which resembled the acoustic feature of sludge; (F) blood clot was taken out from the common bile duct, and that was because blood stream entered backward into bile duct during sphincterotomy.