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IMAGE INTERPRETATION · HEPATOBILIARY AND GI

Low Gallbladder Ejection Fraction on CCK HIDA

Tc-99m HIDA with CCK infusion (LAO15, 4 min/frame) — gallbladder fills but GBEF = 22% at 59 min, consistent with biliary dyskinesia
Tc-99m HIDA with CCK infusion (LAO15, 4 min/frame) — gallbladder fills but GBEF = 22% at 59 min, consistent with biliary dyskinesia

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Question

A Tc-99m HIDA scan with CCK (cholecystokinin) stimulation is performed in a patient with chronic right upper quadrant pain. The gallbladder fills normally but after CCK infusion, the gallbladder ejection fraction (GBEF) is calculated at 22% (normal >35%). This finding is MOST consistent with:

  1. AAcute cholecystitis — cystic duct obstruction by an impacted calculus causing gallbladder wall edema, pericholecystic fluid, and absent filling on standard HIDA imaging without requiring CCK provocation
  2. BChronic cholecystitis (biliary dyskinesia) — impaired gallbladder contractility with reduced GBEF
  3. CCommon bile duct obstruction — elevated biliary backpressure causing uniform dilatation of the biliary tree with prolonged tracer transit and paradoxical gallbladder hyperconcentration due to increased absorption time
  4. DNormal gallbladder function — GBEF values between 20–35% represent a borderline physiologic range attributable to CCK infusion rate variability, fasting duration, or interobserver ROI placement differences
Show the answer and explanation

B. Chronic cholecystitis (biliary dyskinesia) — impaired gallbladder contractility with reduced GBEF

Gallbladder ejection fraction (GBEF) is measured on CCK-HIDA scan by calculating the percentage of gallbladder activity ejected after CCK infusion: GBEF = [(Maximum GB counts – Minimum GB counts) / Maximum GB counts] × 100%. Normal GBEF is >35% (some use >38% or >40%). A reduced GBEF (<35%) indicates impaired gallbladder contractility, consistent with chronic cholecystitis / biliary dyskinesia. This diagnosis explains chronic RUQ pain in patients with normal ultrasound (no stones). Cholecystectomy in patients with reduced GBEF and typical biliary-type pain relieves symptoms in ~90% of cases. The GBEF can also be low in prolonged fasting, TPN, or opioid use.

More hepatobiliary and gi images

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← Acute Cholecystitis on HIDA Scan with MorphineBiliary Atresia on Neonatal HIDA Scan →

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