Disparate dilatation of the intrahepatic and extrahepatic bile ducts in surgical jaundice

Animal model of bile duct dilatation created with minimally invasive surgery

RATIONALE AND OBJECTIVES

The purpose of the study was to evaluate a method of producing obstruction of the common bile duct and concomitant biliary duct dilatation in an animal model.

MATERIALS AND METHODS

Laparoscopic placement of a double-balloon occlusion device was used to produce common bile duct obstruction and bile duct dilatation in pigs.

RESULTS

One week after the procedure, common bile duct obstruction and dilatation of the biliary tree were demonstrated with either percutaneous transhepatic cholangiography or percutaneous cholecystography.

CONCLUSION

The use of this method is technically feasible and provides a useful subacute and chronic animal model of common bile duct obstruction and dilatation of the biliary tree for percutaneous interventional training and research purposes.

Sonographic evaluation of the common bile duct in cats

Ultrasound is an excellent imaging tool in the evaluation of the biliary tract in cats. Extrahepatic obstruction could be diagnosed by the presence of dilated common bile duct (CBD), which was measured ventral to the portal vein in the porta hepatis. At this level, the diameter of the CBD in 6 healthy cats and in 22 cats with nonsurgical jaundice was < or = 4 mm. Six of 7 cats with a CBD > 5 mm had extrahepatic biliary obstruction.

Value of sonography in obstructive jaundice. Limitations of bile duct caliber as an index of obstruction

The diagnostic value of sonography was assessed in 176 patients with jaundice who had a final diagnosis on the basis of surgery, autopsy, liver biopsy, endoscopic retrograde cholangiopancreatography, and serum tests positive for hepatitis A and B. Obstructive (n = 113) versus nonobstructive jaundice (n = 63) was diagnosed with a sensitivity of 91% and a specificity of 95%. Nine of the 10 false negatives had choledocholithiasis. Application of stricter criteria for common duct (CD) dilatation than the one used of CD greater than or equal to 8 mm to greater than or equal to 12 mm would have lowered the sensitivity from 91% to 84%. On the basis of these criteria the predicted level of obstruction would have shifted from distal to proximal in 36% of the patients. Choledocholithiasis was more often associated with decreasing bilirubin values than malignancy: 55% versus 9% (p less than 0.05). The present study indicates that intermittent obstruction, usually associated with choledocholithiasis, constitutes the main problem in detection of obstructive jaundice. Diameter criteria used for diagnosing dilatation of the CD may greatly influence sonographic accuracy.

Imaging of the liver, biliary tract, and pancreas

The interaction between the various noninvasive and invasive imaging modalities used to evaluate the liver, biliary tract, and pancreas is demonstrated in this article. By understanding this interaction and correlating noninvasive studies, the clinician will avoid diagnostic redundancy and the need for invasive testing may be reduced.

Effect of aging on common bile duct diameter: a real-time ultrasonographic study

Using a high-resolution real-time scanner, a technique has been established in our laboratory for visualizing the entire extrahepatic bile duct with multiple longitudinal oblique approaches and, if necessary, several transverse scans through the pancreatic head. To determine the normal size of the extrahepatic bile duct and to evaluate the effect of aging on the duct diameter, 256 healthy subjects and patients without hepatobiliary disease were examined using this technique from January to August, 1982. The entire extrahepatic duct was detected in 203. The inner diameter of the widest point of the duct varied from 1 mm to 10 mm, and was found to be age-dependent (r = 0.60, P less than 0.001). It is concluded that, based on the visualization of the entire extrahepatic duct echographically, the normal inner diameter of common bile duct can be up to 10 mm, and there is a mild change of duct size with age.

Current concepts in diagnosis. Approach to the patient with cholestatic jaundice

On the basis of clinical evaluation, the physician should decide whether extrahepatic biliary obstruction is highly unlikely, possible, or very likely. If it is highly unlikely, no further workup for obstruction is indicated unless the clinical picture is altered on follow-up examination. Further evaluation of the biliary tree is warranted in other patients. Ultrasonography is currently the noninvasive imaging technique of first choice. Computed tomography is indicated if ultrasonography has yielded technically inadequate results or in special circumstances when it is anticipated that decisions regarding further diagnostic evaluation or treatment will be importantly influenced by the results. Negative findings obtained in a technically adequate examination may represent a logical stopping point in the workup of patients in whom obstruction is considered merely a possibility to be excluded, but they should not dissuade the clinician from further diagnostic evaluation if obstruction is considered very likely. Indeed, in selected circumstances, such as cases in which choledocholithiasis is suspected after cholecystectomy, direct cholangiography is appropriate as an initial test. If evidence of obstruction is obtained by noninvasive imaging, direct cholangiography will be required in many patients before treatment, and the choice between percutaneous or retrograde cholangiography should be made on an individual basis. The challenge to the clinician is to minimize the risk, expense, and time involved in obtaining sufficient information for a definitive diagnosis and treatment.

Biliary scintigraphy: comparison with other modern techniques for evaluation of biliary tract disease

The recent availability of iminodiacetic acid analogues labeled with technetium Tc 99m provides a safe and accurate noninvasive test of biliary function. Biliary scintigraphy is a simple and rapid method of detecting acute cholecystitis in particular but also of distinguishing acute biliary pancreatitis from nonbiliary pancreatitis, of evaluating the patency of the common duct in early obstruction, of assessing possible postcholecystectomy syndrome, of evaluating the patency of a biliary enteric bypass, and of detecting postoperative biliary leaks.