[Ultrasound cystometry for estimating residual urine (author's transl)].

The volume of urine in the bladder can be sufficiently accurately calculated in adults by ultrasound measurement of width, height and depth of the bladder and multiplication of these results by 0.57. The method is time saving, non-stressful, easy to learn and can be performed with any ultrasound apparatus. Diagnostic catheterisation can be avoided in many cases. In addition changes of form and position of the bladder can be exactly determined.