Devrim Ersahin MD, Presenter: Nothing to Disclose

Manijeh Zehtabchi MD, Abstract Co-Author: Nothing to Disclose

David Cheng MD, PhD, Abstract Co-Author: Nothing to Disclose

Lawrence H. Staib PhD, Abstract Co-Author: Nothing to Disclose

To determine the significant correlation between ultrasonography (US) findings and hepatobiliary scintigraphy (HIDA scan) results in the evaluation of acute cholecystitis.

Diagnosis of acute cholecystitis can be challenging. US is relatively inexpensive, can be performed at the bedside, and does not cause any radiation exposure to the patient. However, optimal conditions for US cannot always be controlled, and the findings are often times equivocal. HIDA scan has a high accuracy (98%) and high specificity (100%)1. Correlation between various ultrasonographic findings and a positive HIDA scan, which is considered the gold standard for assessment of acute cholecystitis, may help improve its sensitivity, specificity, and accuracy. We reviewed 180 consecutive HIDA scans following right upper quadrant US for indication of acute cholecystitis to assess the best correlation between these imaging modalities. Abnormal ultrasonographic findings including presence of gallstones, impacted stone in the cystic duct, sludge, gallbladder (GB) distention, GB wall thickening, air in GB wall, pericholecystic fluid, dilated common bile duct, intrahepatic biliary dilatation, Murphy's sign, and combination of findings were considered for each patient. Overall impression of US studies were classified as negative, positive, and equivocal. HIDA scan results were either negative or positive. Three patients with equivocal HIDA results due to severe hepatic dysfunction were excluded.

There was poor association between overall impressions of US findings and HIDA scan. When equivocal US results were regarded as positive, the sensitivity of US was 75%. When they were regarded as negative, the specificity was 92%. When we looked at the individual US finding, intrahepatic dilatation had the highest (77%) and GB wall thickening had the lowest accuracy (54%). Cholelithiasis was the most sensitive US finding (61%), but was the least specific (53%). The most specific finding was air in the GB wall (100%), but it was the least sensitive (5%).

Common US findings considered suspicious for acute cholecystitis were found to be nonspecific when compared to HIDA scan results.

Diagnosis of acute cholecystitis can be challenging. Assessing the sensitivity, specificity, and accuracy of various US findings may help clinicians for further management.

Ersahin, D, Zehtabchi, M, Cheng, D, Staib, L, Which Ultrasonography Findings Correlate Best to Hepatobiliary Scintigraphy Results?.  Radiological Society of North America 2010 Scientific Assembly and Annual Meeting, November 28 - December 3, 2010 ,Chicago IL. http://archive.rsna.org/2010/9011549.html