Gallstones

What it means

The gallbladder stores bile, a digestive fluid made by the liver, and releases it into the bowel after meals. Over time, the chemicals in bile can crystallise and clump together into hardened stones. They range from grains of sand to pebbles a few centimetres across. On a CT or MRI, the radiologist usually sees them as bright or dark spots inside the gallbladder, and may also comment on the thickness of the gallbladder wall and any surrounding fluid.

Why it appears on a CT or MRI report

Reports typically describe the number (one, several, many), the size of the largest, and whether the gallbladder itself looks normal or inflamed. Key modifiers include wall thickening, fluid around the gallbladder, and whether a stone is stuck in the neck of the gallbladder or in the bile duct further downstream. If the duct system is widened or the pancreas looks irritated, the radiologist will say so, because a stone that has migrated downstream is treated very differently from one sitting peacefully in the gallbladder.

What it usually means

Quiet stones are remarkably common — by age 60, around 10–15% of adults have them, and most live their whole lives without symptoms. They are more likely in women, in people with higher body weight, after rapid weight loss, during pregnancy, and in those with a family history. The medical conversation changes when a stone moves. A stone blocking the gallbladder's neck causes biliary colic — episodes of severe, gripping pain in the right upper belly that typically come after fatty meals. A stone that sets off inflammation of the gallbladder (cholecystitis) brings persistent pain, fever, and tenderness. A stone that slips into the bile duct can cause jaundice, infection, or pancreatitis. Treatment is usually keyhole removal of the whole gallbladder when symptoms become recurrent or complicated.

When to follow up

For stones found by chance with no symptoms, the usual approach is watchful waiting — most never cause trouble. Talk to your doctor about the report so it is on your record, and mention any history of pain after meals. Severe pain in the right upper belly or upper middle of the abdomen, especially with vomiting, fever, yellow skin or eyes, dark urine, or pale stools, is a red-flag combination that warrants prompt medical attention — sometimes same-day. Recurrent painful episodes are usually the trigger for a surgical referral.

A plain-language way to picture it

Think of the gallbladder as a small storage flask of concentrated bile. Over time, if the mixture is rich enough, tiny crystals settle to the bottom — the same way sugar can crust out of an old syrup bottle. Most of those crystals just rattle around quietly when the flask squeezes. Trouble only starts when one is the wrong size and shape to wedge into the neck or the pipe leading out, blocking the flow.