Utility of Endoscopic Ultrasound Is Safe and Accurate in the Evaluation of Abnormal Intraoperative Cholangiograms

Abstract

Background: There is no consensus on the imaging modality for evaluating abnormal post-cholecystectomy intraoperative cholangiograms (IOC). IOC usage in laparoscopic cholecystectomy is increasing in order to evaluate retained common bile duct stones. Common bile duct stones are detected in 17% of post-cholecystectomy cases. The gold standard in evaluating the biliary system, and for choledocholithiasis, has been endoscopic retrograde cholangiopancreatography (ERCP), however this procedure is associated with increased morbidity and mortality when compared to endoscopic ultrasound (EUS). EUS has been shown in previous studies to have a sensitivity 88-97% and specificity of 96-100% in the evaluation of patients with suspected choledocholithiasis. There has not been a study published to date in which EUS performance was evaluated in the setting of an abnormal IOC. Methods: A retrospective study to evaluate the utility of EUS imaging of the extrahepatic biliary system for abnormal IOC. All medical records for EUS performed in the setting of an abnormal IOC since 1997 at Scott & White Hospital were reviewed. Positive EUS results for choledocholithiasis were confirmed by direct visualization of stones in the duodenum after ERCP extraction or ERCP which showed cholangiogram with filling defects that resolved after extraction. Negative EUS results were considered if the patient had a negative EUS for choledocolithiasis and remained symptom free (no abdominal pain, cholangitis or LFT abnormalities) on follow up of at least 6 months. Results: A total of 62 patients met inclusion criteria. Age ranged from 14 to 89 years of age, mean age 54 years of age, with 37% male and 63% female. There were 34 cases with a negative EUS result, 13 were excluded for inadequate follow up of six months. For all cases there was no evidence of a missed stone (no abdominal pain, cholangitis or LFT abnormalities) at 6 months follow up. There were 28 cases with positive EUS results all of which had conformation of common bile duct stones at ERCP. In 26 cases there was direct visualization of the stone in the duodenum after extraction and 2 cases with filling defects on cholangiogram that resolved after extraction. EUS evaluation of an abnormal IOC has a sensitivity of 85-100% and specificity of 81-100% with 95% confidence interval. There were no complications from any EUS. Conclusion: The results of this study confirm EUS is highly reliable method of evaluating abnormal intraoperative cholangiograms. The increased use of endoscopic ultrasound should reduce morbidity and mortality associated with unnecessary ERCP and reduce overall costs and length of hospital stay.