Gallbladder Sludge on Ultrasound
Gallbladder sludge is a common finding on ultrasounds done of the gallbladder. The gallbladder stores bile used to help with digestion. Bile passes from the gallbladder into the bile duct and into the intestine. Biliary sludge is also called bile sand, debris or thick bile. It consists of sediment that has precipitated from bile in the gallbladder.
Gallbladder sludge can cause problems such as biliary colic or gallbladder attacks, pancreatitis or inflamed pancreas and inflamed bile ducts or cholangitis. Many patients remain without symptoms. Predisposing factors include alcohol use, pregnancy, rapid weight loss, severe illness and following surgery.
On ultrasound, sludge most commonly forms a fluid-fluid level. The sludge is seen at the bottom of the gallbladder forming a sharp interface with the normal bile above it. Sludge is usually whiter in appearance then the normal bile. There is no shadow behind it like you see with gallstones. Sludge will slowly change when the patient is moved into different positions.
Less common appearances of sludge can be mass like, called tumefactive sludge. This has the appearance of a gallbladder mass. Unlike a true solid mass, there is no visible blood flow and it can sometimes move in position. In those cases where it remains unclear, an MRI exam may help with sorting out the possibilities. Another option is a short term follow up ultrasound in 2-4 weeks. A mass will not go away whereas sludge may clear or have a different appearance.
Complications of sludge are similar to gallstones. The sludge can block the gallbladder and cause a Gallbladder attack or acute cholecystitis (inflamed gallbladder). The sludge may pass into the bile duct and cause a blockage, pain and inflammation. The sludge can also cause pancreatitis or inflamed pancreas.
Many people are asymptomatic and require no treatment. A change in lifestyle or removal of a risk factor may make sludge go away. Surgery may be needed for those who have pain or other complications. Additional imaging other than ultrasound may be needed if a complication is suspected or it is not certain that sludge is causing the symptoms you are having.