Real-time ultrasound measurement of bladder volume: a comparative study of three methods.

The accuracy of different ultrasound methods for determining the volume of urine in the bladder was compared using three methods in current use. Each method was applied to the same ultrasound images from 16 patients with prostatic hypertrophy. The calculated volumes were compared with the true volumes derived by measurement of voided and catheter-drained urine. All methods showed similar degrees of accuracy in quantifying bladder volumes. The range of errors of the best method tested was +/- 35% of true volume and this suggests that ultrasound measurement of bladder volume is not sufficiently accurate for many clinical and research applications.