A Novel Strategy for Evaluating Gallbladder Contraction Function by Ultrasound

The most commonly used methods for assessing gallbladder emptying function are radionuclide imaging and ultrasonography. Radionuclide imaging, although effective, has several limitations including lengthy examination time, relatively high costs, and reliance on radioactive isotopes, which has led to its gradual replacement by ultrasonography in clinical practice. Ultrasonography offers significant advantages as a non-invasive modality, providing highly accurate functional evaluations through quantitative analysis. This method objectively reflects gallbladder contraction and emptying capabilities with minimal human interference and demonstrates high reproducibility. Assessment of gallbladder contractile function requires the patient to perform an ultrasound examination on an empty stomach to measure the length, transverse and anterior and posterior diameters of the gallbladder, thus calculating the volume of the fasting gallbladder. The patient is then given a fat meal (usually 2 fried eggs), and the ultrasound examination is performed again 60 minutes after eating to measure the volume of the gallbladder. Gallbladder contractile function is assessed by comparing changes in gallbladder volume on an empty stomach and after a meal. Under normal circumstances, the contraction rate of the gallbladder should reach a certain level. It is generally considered normal to have a contraction rate greater than 30% -50%. However, eating a fat meal, because the fat content of the food itself cannot be accurately determined, will bring inaccurate factors to the evaluation of gallbladder contractile function, such as eating fried eggs, because the variety, size, and quantity of eggs are different, the cooking oil used is different, and the amount of cooking oil remaining on the fried eggs is also different resulting in a large difference in the content of fat in the human body when orally ingested, ultimately leading to an inaccurate evaluation of gallbladder contractile function. Notably, cholesterol in fried eggs may intensify clinical manifestations of cholecystitis, thus necessitating caution when recommending fried eggs to patients with active gallbladder inflammation. Therefore, a prospective, single-center, single-blind, cross-over trial was conducted to verify whether oral functional fatty acids can be used to effectively evaluate gallbladder contractile function.

Inclusion criteria

• Ultrasound assessment identifies people with normal biliary tract structure

Exclusion criteria

• History of Endoscopic Retrograde Cholangiopancreatography
• Previous gallstone removal surgery with gallbladder preservation
• History of acute or chronic pancreatitis, cholangitis
• Mirizzi Syndrome
• History of gastrointestinal surgery
• Gastrointestinal obstruction
• Dysfunction of the sphincter of Oddi
• Gallbladder neck polyps
• Abnormal gallbladder structure
• Gallbladder mass
• Biliary infection or stones
• Congenital biliary abnormalities
• Biliary injury or surgery
• Biliary tumors
• Gastrointestinal bleeding, liver cirrhosis, or other malignant diseases
• Significant arrhythmia, bradycardia, or atrioventricular block
• Severe hypertension, liver or kidney insufficiency
• Immune, endocrine, hematological, or mental disorders
• Severe cerebrovascular disease
• Allergy to relevant foods
• Pregnant or breastfeeding women
• Unwillingness or inability to consent to participation