Oral cholecystography in contemporary gallstone imaging: a review
Article Abstract:
Oral cholecystography (OCG) is a technique whereby the gallbladder is X-rayed after an orally administered contrast agent is given to the patient. The importance of this technique has resurfaced as new techniques for treating gallstones have been developed. These new techniques require accurate information regarding size, location, number, and composition of gallstones. Iopanoic acid is the most popular contrast agent in use in the United States. It requires the presence of fat for efficient absorption, thus patients should ingest a meal high in fat prior to taking it. Other contrast agents should be used in patients who cannot ingest such a meal. The two-day consecutive dosage schedule for ingestion of the agent results in the fewest false positive results and lessens the number of repeat examinations. Water intake should be high to prevent toxicity and kidney problems. A preliminary abdominal X-ray can be useful to check the presence of gallstone calcification, an important factor in deciding which of the new treatments to use. X-rays of the gallbladder itself should be taken from different views and from different patient positions, because gallstones will localize in different spots in the gallbladder depending on the patient's position and anatomical changes in the gallbladder. The X-ray should not be taken right after a fatty meal as was once the common practice. OCG should give clear visualization of the gallbladder. Failure can usually be attributed to failure to take the contrast agent or the presence of disease or the prior surgical removal of the gallbladder. Sonography has recently been introduced as a technique for imaging the gallbladder that does not require a contrast agent. However, OCG is still the better technique for counting and sizing gallstones. OCG can also be used to detect the composition of gallstones. OCG can also be used to determine possible risks of future gallbladder disease. The possible uses of OCG require careful patient preparation and use of contrasting agents. Radiologists must also be careful in the X-ray procedure itself and in interpreting the results of the X-rays. When careful procedures are followed, OCG is a useful and sensitive diagnostic tool. (Consumer Summary produced by Reliance Medical Information, Inc.)
Publication Name: Radiology
Subject: Health
ISSN: 0033-8419
Year: 1991
User Contributions:
Comment about this article or add new information about this topic:
Role of CT in characterizing gallstones: an unsettled issue
Article Abstract:
Gallstones can be treated with surgery or with nonsurgical techniques. Determining gallstone composition is important for deciding the type of treatment to be used. A number of investigators have indicated that computed tomography (CT) could be useful in characterizing gallstone composition. CT produces computer-generated images from scanning X-rays. Research has shown that CT can be used to determine cholesterol and calcium content of gallstones. Some researchers have concluded that this information can be used to decide which treatment is appropriate for a given patient. Other researchers question this use of CT, citing its cost and variable accuracy, and contending that its use is limited to only 10 percent of gallstone cases. While agreeing that these researchers bring up valid points, the author notes that there are responses to these points. Nonsurgical techniques for removing gallstones are relatively new. As their acceptance increases, stone determination increases in importance, and regular X-rays are not sufficiently accurate for this use. A review of the research used to contend that CT is only useful in 10 percent of cases actually shows a figure of at least 17 percent. Also, cholesterol stones that can be seen by regular X-ray can have physical differences that cannot be detected without CT. Regular X-ray can only classify stones as either opaque or lucent. CT can possibly be used to classify stones in a number of ways. The ways in which CT can characterize stones have not been fully researched as to their value in determining stone composition for deciding type of treatment. This type of determination is necessary if nonsurgical treatments of gallstones are going to be used. (Consumer Summary produced by Reliance Medical Information, Inc.)
Publication Name: Radiology
Subject: Health
ISSN: 0033-8419
Year: 1991
User Contributions:
Comment about this article or add new information about this topic:
- Abstracts: Oral corticosteroid therapy for patients with stable chronic obstructive pulmonary disease: a meta-analysis. Long-term effects of inhaled corticosteroids on FEV(sub 1) in patients with chronic obstructive pulmonary disease: a meta-analysis
- Abstracts: Medical educators' views on medical education reform. Are we mortgaging the medical profession? Preparedness for practice: young physicians' views of their professional education
- Abstracts: Malignant peripheral neuroectodermal tumor and its necessary distinction from Ewing's sarcoma: a report from the Kiel Pediatric Tumor Registry
- Abstracts: Are there alternatives to dental amalgam? Resin restorations for anterior teeth - 1995. Amalgam vs. composite resin: 1998
- Abstracts: Studies of atomic bomb survivors: understanding radiation effects. Mortality among workers at Oak Ridge National Laboratory: evidence of radiation effects in follow-up through 1984