Variability of Gallbladder Emptying after Oral Stimulation

Abstract

Background: To date, the intraindividual reproducibility of fasting and postprandial gallbladder (GB) volumes has not been established satisfactorily. Hence we examined the variability of postprandial GB motility, using the biplane Simpson method as a new sonographic tool for GB volume determination. Methods: The biplane Simpson method was validated in vitro and in vivo and compared with the sum-of-cylinders method. Thereafter, postprandial GB emptying after a defined test meal was examined in 10 healthy volunteers over 108 min on days 1,31, and 61. Results: The results of the biplane Simpson method correlated with real volumes (r = 0.99) and provided a intra- and inter-observer variation of less than 5%. Intraindividually, differences in fasting GB volume ranged from 1.9 to 24.0 ml within the observation period. The patterns of GB emptying also showed fluctuations characterized by a rather large inter-individual and intraindividual variability. Conclusions: The biplane Simpson method is a reliable tool for measuring GB volumes. The fasting and the postprandial GB volumes vary considerably within individuals when measured over a period of 2 months.

Key Words:

• Gallbladder emptying
• gallbladder volume
• intraindividual reproducibility
• longitudinal studies
• Simpson method
• sum-of-cylinders method
• ultrasonography