Investigation of choice for acute cholecystitis: March 2010
**Core Concept**
In acute cholecystitis, the investigation of choice is a diagnostic imaging modality that can accurately visualize the gallbladder, bile ducts, and surrounding tissues. This modality should be able to detect signs of inflammation, such as gallbladder distension, wall thickening, and pericholecystic fluid.
**Why the Correct Answer is Right**
Ultrasound is the investigation of choice for acute cholecystitis because it is non-invasive, quick, and highly sensitive for detecting gallstones and gallbladder inflammation. Ultrasound can also evaluate the liver, bile ducts, and surrounding tissues for signs of infection or perforation. The sensitivity of ultrasound for detecting gallstones is high, especially in the presence of acute inflammation.
**Why Each Wrong Option is Incorrect**
**Option A:** CT scan of the abdomen is not the first-line investigation for acute cholecystitis, although it can be used in complex cases or when ultrasound is inconclusive.
**Option B:** MRCP (Magnetic Resonance Cholangiopancreatography) is an excellent imaging modality for bile duct pathology, but it is not the first-line investigation for acute cholecystitis.
**Option C:** ERCP (Endoscopic Retrograde Cholangiopancreatography) is a therapeutic procedure that can be used to treat bile duct pathology, but it is not a diagnostic imaging modality.
**Clinical Pearl / High-Yield Fact**
In cases of suspected acute cholecystitis, ultrasound should be performed as soon as possible to guide management and prevent delays in treatment.
**Correct Answer: A. Ultrasound.**