A HIDA (Hepatobiliary Iminodiacetic Acid) scan is a diagnostic imaging procedure used to evaluate the function of the liver, gallbladder, and bile ducts. This non-invasive test helps medical professionals assess how bile flows through the digestive system and identify potential issues.
Understanding the HIDA Scan
A HIDA scan is a nuclear medicine imaging procedure that tracks the path of bile. It involves injecting a small amount of radiotracer into the bloodstream. This tracer is absorbed by the liver’s bile-producing cells and then travels with the bile into the gallbladder and the small intestine.
Special cameras detect the energy emitted by the radiotracer, creating detailed images of these organs to assess bile movement and gallbladder function. It helps diagnose conditions such as acute cholecystitis, chronic gallbladder inflammation, bile duct blockages, and bile leaks after surgery. This test can also evaluate liver transplant function.
How Long Does a HIDA Scan Last?
The typical duration of a HIDA scan ranges from one to four hours. In some instances, the procedure might be as short as 30 minutes or extend longer depending on how quickly the radiotracer moves through the patient’s system. The total time is influenced by several factors, including the specific protocol and individual patient characteristics.
Initial imaging begins shortly after the radiotracer injection, with images taken as the tracer moves from the liver into the gallbladder and small intestine. If the gallbladder does not visualize promptly, delayed images may be necessary, potentially extending the scan time for several hours or even requiring a return visit up to 24 hours later. An additional phase often involves administering CCK (cholecystokinin), or sincalide, to assess the gallbladder’s ability to contract and release bile. This measures the gallbladder ejection fraction and adds to the overall duration, potentially extending the procedure by 20 to 50 minutes.
What to Expect During Your HIDA Scan
Preparation for a HIDA scan requires fasting for four to six hours. Patients should discuss all medications and supplements with their doctor, as some, particularly opioid pain medications, may need to be avoided. Informing the healthcare provider about pregnancy or breastfeeding is also important, as these conditions may require postponing the scan or specific precautions.
Upon arrival, patients change into a gown. An intravenous (IV) line is inserted, typically in the arm or hand, for the radiotracer injection. The injection is well-tolerated, though some may feel a brief cold sensation or mild pressure. Patients then lie still on a scanning table while a special camera is positioned over the abdomen to capture images as the tracer moves through the body. Remaining still is important to ensure clear image quality.
If evaluating gallbladder function, CCK is administered intravenously. The CCK causes the gallbladder to contract, which may lead to mild abdominal cramping or discomfort similar to the original symptoms. Additional images are taken during this phase. Once images are collected, which can take several hours, the scan concludes. Patients can resume normal activities immediately, and drinking fluids helps flush the radiotracer; results are then reviewed by the doctor.