Dynamic ultrasonography in the diagnosis of gallbladder dysfunction: reliability of a simple method with easy clinical application

Abstract

Although the results of dynamic ultrasonography (DUS) are similar to those of dynamic cholescintigraphy (DCS) in the study of gallbladder function, the methodology required for this technique is laborious and sometimes complex. The aim of this study was to investigate the reliability of a simple method of DUS to evaluate gallbladder function using DCS as a reference. Gallbladder function was studied using DUS and DCS in 80 consecutive patients with clinical findings compatible with gallbladder dysfunction. For DUS the ellipsoid method was used with measurement of three gallbladder diameters (transversal, longitudinal and anteroposterior) in basal conditions and after applying a cholecystokinetic stimulus (meal test); gallbladder emptying of less than 50% was considered abnormal. In DCS intravenous cholecystokinin (CCK) (0.40 IDU/kg in 20 minutes) was used as stimulus and an ejection fraction < or = 40% was considered abnormal. In 15 patients (19%; 95% CI, 11-29%) abnormal gallbladder response was found using DUS. The ejection fraction in the entire group of patients studied was 48 26.2%. Ejection fraction was abnormal in 41 patients (51%; 95% IC, 40-63%) with a value of 25 8.5% and was normal in 39 patients (49%; 95% IC, 40-63%) with a value of 71.5 14.5%. The correlation coefficient between the values of gallbladder emptying calculated with DUS and the ejection fraction obtained with DCS was 0.199 (p = 0.079). When patients were divided according to gallbladder emptying measured by DUS and the ejection fraction obtained with DCS the concordance was very low (k = 0.065; EE = 0.085). DUS performed using a simple technique lacks diagnostic value in gallbladder dysfunction when DCS is taken as a reference test