[Ultrasound evaluation of gallbladder function using planimetry].

Fourteen patients with gallstones (13 female, 1 male; mean age 45.1 +/- 14.6 years; mean body weight 105.7% +/- 18.7% of ideal body weight) were included in the present study. Prior to and 45 min. after administration of a standard fatty meal, patients were examined by ultrasound. The mean gallbladder volume decreased from 20.94 +/- 10.0 cm3 to 6.83 +/- 3.5 cm3 (ejection fraction (EF) = 61.7 +/- 27.9%), the mean cross-sectional area from 12.0 +/- 3.4 cm2 to 6.0 +/- 2.8 cm2 (percentage changes 48.0% +/- 25.5%). A correlation is shown to exist between the ejection fraction of gallbladder emptying and the decrease of gallbladder area (r = 0.91; p less than 0.001). The simple measurement of the gallbladder area of a section through the long axis adequately demonstrates gallbladder contraction.