Sonographic measurements of the normal bladder wall in children.

The thickness of the bladder wall was measured sonographically in 410 children (1 day to 19 years old) and in 10 adults. None had complaints related to the urinary tract. The bladder wall thickness varied mostly with the state of bladder filling and only minimally with age and gender. The normal bladder wall had a mean thickness of 2.76 mm when the bladder is almost empty and 1.55 mm when it is distended. There is a linear relationship between bladder fullness and bladder wall thickness; the upper limits are 3 and 5 mm for a full or empty bladder respectively.