Prostatic Volume Estimation (Ultrasonography)

The probe is first placed transversally above the symphysis. In this patient the bladder is almost empty, but the examination can also be performed (even better) with full bladder. Prostatic volume measurement can be performed at the same time with residual urine measurement. To improve visibility the probe often needs to be compressed downwards. Tilt the probe to find a view that shows the prostate in its maximum size. Freeze the view and measure the horizontal (47.5 mm) and vertical (50.8 mm) dimensions of the prostate. Turn the probe to a longitudinal position, and find the maximum longitudinal dimension (46.9 mm) of the prostate. To improve visibility the probe often has to be compressed downwards and the sound beam directed under the symphysis. The position of the lower border of the prostate sometimes has to be "guessed". The equation for prostatic volume estimation is the same as for residual urine volume volume: 0.6 × a × b × c. If the dimensions are given in cm, the result is in ml. In this patient the volume was 0.6×4.8×5.1×4.7 = 69 ml. A prostate < 20 ml is normal (= the size in a young man), and > 40 ml is clearly enlarged.

Prostatic Volume Estimation (Ultrasonography)