the oral cholecystogram, or ocg, is a radiologic process for diagnosing gallstones. an oral cholecystogram is in comparison to an intravenous cholangiogram (ivc). the oral cholecystogram is hardly ever used, as ultrasound or ct are greater accurate, faster techniques for figuring out gallstones with out exposure to iodine.
for an ocg, the affected person takes iodine-containing capsules with the aid of mouth for one night or two nights in a row. the iodine is absorbed from the intestine into the bloodstream, eliminated from the blood with the aid of the liver, and excreted by means of the liver into the bile. the iodine, collectively with the bile, is fantastically focused inside the gallbladder. iodine is used in an ocg because it's miles dense and radioopague (stops x-rays). it outlines the gallstones that are radiolucent (x-rays skip through them) and which might be generally invisible on x-ray.
the bile ducts themselves cannot be seen at the x-ray in an ocg due to the fact the iodine isn't always focused within the ducts. therefore, any gallstones lodged in the ducts will go undetected on ocg.
failure to visualise the gallbladder on an ocg may also occur for one among reasons. first, a gallstone can also have obstructed the cystic duct and averted the iodine-containing bile from getting into the gallbladder. 2d, infection of the gallbladder -- normally due to gallstones -- may additionally have interfered with the gallbladder's capacity to pay attention bile and iodine. whichever the reason, failure to visualise the gallbladder on an ocg strongly suggests a diseased gallbladder.
the risks of an oral cholecystogram are few. one, of route, is the radiation. however, in an ocg there may be a pretty small quantity of radiation from the x-rays.
every other threat involves the iodine. some human beings are allergic to iodine. fortunately, most of the people who're allergic understand that they are, and therefore do no longer go through the take a look at.