Significance of the nonopacified gallbladder in endoscopic retrograde cholangiography

The cystic duct: normal anatomy and disease processes

The cystic duct can be depicted with a variety of imaging modalities but is optimally visualized with direct cholangiography or magnetic resonance cholangiopancreatography. Nevertheless, unrecognized anatomic variants of the cystic duct may cause confusion on imaging studies and complicate subsequent surgical, endoscopic, and percutaneous procedures. Primary entities involving the cystic duct include calculous disease, Mirizzi syndrome, cystic duct-duodenal fistula, biliary obstruction, neoplasia, and primary sclerosing cholangitis. The cystic duct may also be secondarily involved by adjacent malignant or inflammatory processes. Postoperative alterations are seen after liver transplantation or cholecystectomy when a portion of the cystic duct is left behind as a remnant. Recognized postoperative complications include retained cystic duct stones, cystic duct leakage, and malposition of T tubes in the remnant. Pitfalls encountered in cystic duct imaging include pseudocalculous defects from overlap of the cystic duct and common bile duct, underfilling of the cystic duct during direct cholangiography, and admixture defects at the cystic duct orifice. Pseudomass or pseudotumor defects may result from an impacted cystic duct stone or from a tortuous, redundant cystic duct. Familiarity with the imaging appearance of the normal cystic duct, its anatomic variants, and related disease processes facilitates accurate diagnosis and helps avoid misinterpretation.

Gallbladder non-filling: an indication for cholecystectomy after endoscopic sphincterotomy

The place of endoscopic sphincterotomy in the treatment of common duct stones leaving the gallbladder in situ remains controversial. Over a 3-year period, 20 elderly high-operative-risk patients with stones in the common duct and intact biliary tree were treated by endoscopic sphincterotomy leaving the gallbladder in situ. Two patients underwent cholecystectomy for persistent symptoms after endoscopic sphincterotomy, and 18 patients were discharged from hospital, with the gallbladder intact. Of the 18 patients, 6 developed recurrent gallbladder problems, with 3 of the 6 dying as a result of these problems. On review of our data, these six patients were in a group of eight who, at the time of original endoscopic retrograde cholangiography (ERC), were shown to have an obstructed cystic duct. The other 10 patients, with a patent cystic duct and discharged with gallbladder in situ, remained symptom free over a median follow-up period of 9 (range 2-42) months. We conclude that if the gallbladder does not fill at ERC (indicating probable cystic duct obstruction), cholecystectomy is warranted. When the gallbladder fills, regular follow-up alone is justified in the absence of symptoms.

Analysis of cases of nonvisualized gallbladder by ultrasonography

To define the significance of nonvisualization of the gallbladder by ultrasonography, we studied follow-up data on 31 cases in which the gallbladder could not be identified despite adequate fasting. Thirty one cases of gallbladder disease included 15 cases of chronic cholecystitis due to cholelithiasis (13 cases) and choledocholithiasis (2 cases), 4 cases of cholelithiasis which were not surgerized, and 3 cases of cancer. There were 4 cases of diagnostic error in which gallbladder nonvisualization occurred despite a demonstrable lumen. The etiology of disease was not determined in the 5 remaining cases. Therefore 22 of 26 cases were found to have diseased gallbladders. The resasons for nonvisualization of the gallbladder by ultrasonography in the 19 cases which underwent surgicl exploration were: 17 cases due to chronic cholecystitis with cholelithiasis (13 cases), choledocholithiasis (2 cases) and cancer (2 cases), obliteration of the lumen due to cancer of the gallbladder in one cases, and technical error due to an unusual location of the gallbladder in one case. The mechanisms of diagnostic error in 4 cases seemed technical error due to an unusual location of the gallbladder in 3 cases and the obscured gallbladder by intestinal gas in one case. In conclusion, we feel that careful examination should be done to detect a gallbladder located unusually or obscured by intestinal gas in order to decrease the rate of diagnostic error when the gallbladder is not visualized by ultrasonography. Also, we recommend an oral cholecystography or ERCP for ultrasonic nonvisualized gallbladder.