Radiologic and Endoscopic Techniques
Interventional techniques for evaluating the hepatobiliary system
include percutaneous transhepatic cholangiography and endoscopic retrograde cholangiopancreatography.
The former is useful when bile ducts are dilated, whereas the latter can help with
preoperative localization of biliary tract disease. Improved imaging techniques
such as nuclear magnetic resonance may obviate endoscopic examination of biliary
ducts. Nevertheless, endoscopy remains a useful mode for delivering therapy. For
example, papillotomy via endoscopy can eliminate the need for operative removal of
common bile duct stones.[228]
Esophagogastroscopy
is a reliable and simple method for detecting and treating submucosal varices in
the upper digestive tract. If portal hypertension is present, measurement of hepatic
venous pressure may localize anatomic sites of increased resistance to blood flow.
Splenoportography may be useful for delineating abnormalities in the splenic and
portal veins. Using three-dimensional computed tomography (with multi-detector row)
helps create vascular maps whose quality equals or exceeds those from classic angiography.
[229]
This technique is useful for performing portal
venography in patients with cirrhosis. The images can show the extent and location
of portosystemic collateral communications (left gastric, short gastric, paraumbilical,
and abdominal wall veins; esophageal varices; splenorenal and gastrorenal shunts).
Radionuclide and ultrasonic scanning are useful for detecting space-occupying lesions
of the hepatobiliary tree.[228]
[230]
