Gallstones and Gallbladder Disease - Diagnosis

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If the dye does not enter the gallbladder, the cystic duct is obstructed, indicating acute cholecystitis. The scan cannot identify individual gallstones or chronic cholecystitis.

Occasionally, the scan gives false positive results (detecting acute cholecystitis in people who do not have the condition). Such results are most common in alcoholic patients with liver disease or patients who are fasting or receiving all their nutrition intravenously.

Endoscopic Retrograde Cholangiopancreatography (ERCP). Endoscopic retrograde cholangiopancreatography (ERCP) has been the gold standard for detecting common bile duct stones, particularly because stones can be removed during the procedure. (See "Surgery" section below for a description of the procedure.)

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However, this technique is invasive and carries a risk for complications, including pancreatitis. With the advent of noninvasive imaging techniques, ERCP is now generally limited to patients who have a high likelihood of common bile ducts stones, which would need to be removed. It may also be used to diagnose biliary dyskinesia.

Computed Tomography. Computed tomography (CT) scans may be a valuable additional imaging technique if the doctor suspects complications, such as perforation, common duct stones, or other problems such as cancer in the pancreas or gallbladder. Helical (spiral) CT scanning is an advanced technique that is faster and obtains clearer images. With this process, the patient lies on a table while a donut-like, low-radiation x-ray tube rotates around the patient.

Magnetic Resonance Cholangiography (MRCI), or Magnetic Resonance Cholangiopancreatography (MRCP). These imaging techniques may be very useful for detecting common bile duct stones and other abnormalities of the biliary tract. A dye is injected into the patient's veins that helps visualize the biliary tract. MRCP is extremely sensitive in detecting biliary tract cancer. This imaging procedure may not detect very small stones or chronic infections in the pancreas or bile duct. It is most likely to be useful in a small subset of patients who have unclear symptoms that suggest gallbladder or biliary tract problems, but ultrasound and other routine tests have been negative. For these patients, performing a MRCP can eliminate the need for ERCP and its side effects.

Click the icon to see an image of a cholangiogram.

Virtual Endoscopy. Virtual endoscopy is an experimental technique that uses data from CT and MRI scans to generate a three-dimensional view of various body structures. The images resemble those used in endoscopy (an invasive procedure), but the procedure is noninvasive. Virtual endoscopy may be able to detect smaller stones in the common bile duct than MRI.

Review Date: 06/10/2010
Reviewed By: Reviewed by: Harvey Simon, MD, Editor-in-Chief, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org).