Modern gallbladder diagnosis is layered: a focused history and examination tell us what to suspect, blood tests support or exclude obstruction, and imaging confirms the diagnosis. Knowing what each scan does — and what it can't do — helps you understand your results.
Step 1: history & examination
Pain pattern (post-fatty meal), location (RUQ/epigastric), radiation (right shoulder/back), duration, fever, jaundice — and a focused examination including Murphy's sign — already narrow the diagnosis significantly.
Step 2: blood tests
- •FBC and CRP — infection / inflammation
- •Liver function tests (LFTs) — bilirubin, ALT, AST, ALP, GGT detect bile duct obstruction
- •Amylase / lipase — exclude pancreatitis
- •Coagulation profile — pre-operative baseline
Step 3: abdominal ultrasound
The first-line imaging — quick, painless, radiation-free. Detects:
- •Gallstones (95% sensitivity)
- •Gallbladder wall thickening (cholecystitis)
- •Sonographic Murphy's sign
- •Bile duct dilatation
- •Liver, pancreas and kidney findings
Step 4: MRCP (when bile duct stones suspected)
Magnetic Resonance Cholangiopancreatography — a non-invasive MRI of the bile and pancreatic ducts. Used when LFTs suggest obstruction or ultrasound shows duct dilatation. No contrast needed; takes 20–30 minutes.
Step 5: HIDA scan (functional assessment)
Hepatobiliary iminodiacetic acid scan — a nuclear medicine test that measures gallbladder ejection fraction. Reserved for patients with classic biliary pain but a normal ultrasound (suspected biliary dyskinesia). An ejection fraction below 35% supports surgery.
Step 6: CT abdomen
Used for complications: perforation, abscess, gangrenous cholecystitis, or when the diagnosis is unclear. Less sensitive than ultrasound for routine gallstones.
Step 7: ERCP (therapeutic, not screening)
Endoscopic Retrograde Cholangiopancreatography — combines diagnosis with treatment. Used to clear bile duct stones identified on MRCP, before or after cholecystectomy.