T-tube cholangiography and choledochoscopy are commonly used techniques for detecting residual bile duct stones after biliary surgery. However, the utility of routine cholangiography before T-tube removal needs further investigation. This study aims to evaluate the diagnostic efficacy of various methods for detecting residual calculi following biliary surgery.

We retrospectively analyzed the clinical data of 287 adult patients who underwent common bile duct exploration with T-tube drainage, followed by T-tube cholangiography and choledochoscopy, at the Department of General Surgery, Xuanwu Hospital, Capital Medical University, between 2017 and 2022. Exclusion criteria were patients with bile duct tumors, incomplete medical records or loss to follow-up, and patients with contraindications to T-tube or choledochoscopy. McNemanr test and Kappa test were used to compare the results and consistency between choledochoscopy and T-tube cholangiography. All patients underwent both cholangiography and choledochoscopy six to eight weeks after laparoscopic cholecystectomy combined with common bile duct exploration and T-tube drainage. The results of T-tube cholangiography and choledochoscopy for each patient were recorded, analyzed, and compared.

Among the 287 patients, T-tube cholangiography detected residual stones in 38 cases, which were confirmed by choledochoscopy in 29 cases. Conversely, of the 249 patients without evidence of residual stones on T-tube angiography, 11 patient was later found to have retained stones through choledochoscopy. There was no significant difference between the results of T-tube cholangiography and choledochoscopy (P = 0.82), indicating a high level of agreement between the two methods (Kappa value: 0.70) (95% CI, 0.65-0.76).

There is no significant difference in the diagnostic accuracy between T-tube cholangiography and choledochoscopy for detecting residual bile duct stones after surgery (P = 0.82). The two methods demonstrated a high level of consistency (Kappa value: 0.70) (95% CI, 0.65-0.76). The choice of diagnostic method for postoperative residual bile duct stones should be based on the specific condition of the patient.

Endoscopic ultrasound (EUS) and magnetic resonance cholangiopancreatography (MRCP) are tests used in the diagnosis of common bile duct stones in patients suspected of having common bile duct stones prior to undergoing invasive treatment. There has been no systematic review of the accuracy of EUS and MRCP in the diagnosis of common bile duct stones using appropriate reference standards.

To determine and compare the accuracy of EUS and MRCP for the diagnosis of common bile duct stones.

We searched MEDLINE, EMBASE, Science Citation Index Expanded, BIOSIS, and Clinicaltrials.gov until September 2012. We searched the references of included studies to identify further studies and of systematic reviews identified from various databases (Database of Abstracts of Reviews of Effects (DARE), Health Technology Assessment (HTA), Medion, and ARIF (Aggressive Research Intelligence Facility)). We did not restrict studies based on language or publication status, or whether data were collected prospectively or retrospectively.

We included studies that provided the number of true positives, false positives, false negatives, and true negatives for EUS or MRCP. We only accepted studies that confirmed the presence of common bile duct stones by extraction of the stones (irrespective of whether this was done by surgical or endoscopic methods) for a positive test, and absence of common bile duct stones by surgical or endoscopic negative exploration of the common bile duct or symptom free follow-up for at least six months for a negative test, as the reference standard in people suspected of having common bile duct stones. We included participants with or without prior diagnosis of cholelithiasis; with or without symptoms and complications of common bile duct stones, with or without prior treatment for common bile duct stones; and before or after cholecystectomy. At least two authors independently screened abstracts and selected studies for inclusion.

Two authors independently collected the data from each study. We used the bivariate model to obtain pooled estimates of sensitivity and specificity.

We included a total of 18 studies involving 2366 participants (976 participants with common bile duct stones and 1390 participants without common bile duct stones). Eleven studies evaluated EUS alone, and five studies evaluated MRCP alone. Two studies evaluated both tests. Most studies included patients who were suspected of having common bile duct stones based on abnormal liver function tests; abnormal transabdominal ultrasound; symptoms such as obstructive jaundice, cholangitis, or pancreatitis; or a combination of the above. The proportion of participants who had undergone cholecystectomy varied across studies. Not one of the studies was of high methodological quality. For EUS, the sensitivities ranged between 0.75 and 1.00 and the specificities ranged between 0.85 and 1.00. The summary sensitivity (95% confidence interval (CI)) and specificity (95% CI) of the 13 studies that evaluated EUS (1537 participants; 686 cases and 851 participants without common bile duct stones) were 0.95 (95% CI 0.91 to 0.97) and 0.97 (95% CI 0.94 to 0.99). For MRCP, the sensitivities ranged between 0.77 and 1.00 and the specificities ranged between 0.73 and 0.99. The summary sensitivity and specificity of the seven studies that evaluated MRCP (996 participants; 361 cases and 635 participants without common bile duct stones) were 0.93 (95% CI 0.87 to 0.96) and 0.96 (95% CI 0.90 to 0.98). There was no evidence of a difference in sensitivity or specificity between EUS and MRCP (P value = 0.5). From the included studies, at the median pre-test probability of common bile duct stones of 41% the post-test probabilities (with 95% CI) associated with positive and negative EUS test results were 0.96 (95% CI 0.92 to 0.98) and 0.03 (95% CI 0.02 to 0.06). At the same pre-test probability, the post-test probabilities associated with positive and negative MRCP test results were 0.94 (95% CI 0.87 to 0.97) and 0.05 (95% CI 0.03 to 0.09).

Both EUS and MRCP have high diagnostic accuracy for detection of common bile duct stones. People with positive EUS or MRCP should undergo endoscopic or surgical extraction of common bile duct stones and those with negative EUS or MRCP do not need further invasive tests. However, if the symptoms persist, further investigations will be indicated. The two tests are similar in terms of diagnostic accuracy and the choice of which test to use will be informed by availability and contra-indications to each test. However, it should be noted that the results are based on studies of poor methodological quality and so the results should be interpreted with caution. Further studies that are of high methodological quality are necessary to determine the diagnostic accuracy of EUS and MRCP for the diagnosis of common bile duct stones.