Objectives To investigate the prevalence of benign findings of liver, gallbladder, and kidney detected at abdominal ultrasonography.
Design A cross-sectional study.
Setting and Participants The subjects consisted of 2,512,520 cases who consulted 371 institutes for health screening,part of the Japan Society of Health Evaluation and Promotion.
Measurement and Results We classified the prevalence of liver cyst, hepatic hemangioma, gallbladder polyp, gallstone,and renal cyst into 14 groups every five years by gender, and plotted the results. The prevalence of liver cyst, renal cyst,and gallstone increased with age. The prevalence of gallbladder polyp showed a bell-shaped distribution with a peak at 50-54 years. The prevalence of hepatic hemangioma also showed a bell-shaped distribution with a peak at 45-49 years.
Conclusions Liver cyst, renal cyst, and gallstone increase with age, whereas both gallbladder polyp and hepatic hemangioma naturally disappeared.