From the Guidelines
A 0% ejection fraction on a Hepatobiliary Iminodiacetic Acid (HIDA) scan is a strong indicator of gallbladder dysfunction, suggesting chronic cholecystitis or biliary dyskinesia, and warrants further evaluation and potential surgical intervention. This finding implies that the gallbladder is not contracting properly to expel bile after being stimulated with cholecystokinin (CCK) during the scan. According to the most recent guidelines, normal gallbladder ejection fraction is typically defined as ≥38% 1. A 0% result represents complete failure of gallbladder contractility, which can cause symptoms like right upper quadrant pain, bloating, and nausea after meals, particularly fatty ones, despite the absence of gallstones on ultrasound.
Clinical Implications
The condition often warrants surgical intervention through cholecystectomy (gallbladder removal), especially if the patient is symptomatic. The pathophysiology involves either inflammation of the gallbladder wall or dysfunction of the smooth muscle, preventing proper contraction in response to hormonal stimulation. Patients with this finding should discuss treatment options with their healthcare provider, as some may benefit from surgery while others with minimal symptoms might be managed conservatively. It is essential to note that the diagnosis of acute cholangitis should include clinical signs, laboratory findings, and imaging findings, and CT with IV contrast is preferable when CT is obtained for subsequent imaging 1.
Diagnostic Considerations
For suspected acute cholecystitis, if clinical suspicion is high and initial US is equivocal, it may be appropriate to proceed directly from US to HIDA scan. However, if other diagnostic possibilities are being considered for RUQ abdominal pain, it is reasonable to obtain a CT as subsequent imaging before a HIDA scan. The use of a single, standardized CCK-CS protocol, as recommended by an interdisciplinary panel, involves infusion of 0.02 g/kg of sincalide over 60 minutes, which can help establish the utility of CCK-CS in the diagnosis of functional gallbladder disease 1.
Management
In real-life clinical practice, a 0% ejection fraction on a HIDA scan should be managed with caution, and treatment options should be discussed with the patient, considering the potential benefits and risks of surgical intervention. The patient's symptoms, medical history, and overall health status should be taken into account when making a decision. In some cases, conservative management may be appropriate, while in others, surgical removal of the gallbladder may be necessary to alleviate symptoms and prevent further complications.
From the Research
HIDA Scan Ejection Fraction
A 0% ejection fraction on a Hepatobiliary Iminodiacetic Acid (HIDA) scan indicates that the gallbladder is not contracting or emptying properly. This can be a sign of various conditions, including:
- Biliary dyskinesia: a condition where the gallbladder does not contract properly, leading to symptoms such as abdominal pain and nausea 2
- Chronic acalculous cholecystitis: a condition where the gallbladder is inflamed, but no gallstones are present 3
- Sphincter of Oddi dysfunction: a condition where the sphincter of Oddi, which controls the flow of bile into the small intestine, is not functioning properly 3
Diagnostic Implications
A 0% ejection fraction on a HIDA scan can be an indication for further testing or treatment, such as:
- Cholecystectomy: surgical removal of the gallbladder, which can be effective in relieving symptoms in patients with biliary dyskinesia or chronic acalculous cholecystitis 2, 4
- Additional testing: such as endoscopic retrograde cholangiopancreatography (ERCP) or magnetic resonance cholangiopancreatography (MRCP) to evaluate the bile ducts and sphincter of Oddi 5
Clinical Significance
The clinical significance of a 0% ejection fraction on a HIDA scan depends on the individual patient's symptoms and medical history. In some cases, a low ejection fraction may not be a reliable indicator of underlying disease, and additional testing or consultation may be necessary to determine the best course of treatment 3, 6
- Recreation of symptoms following CCK provocation may be a more reliable indicator of underlying chronic cholecystitis than ejection fraction alone 6