Automated evaluation of urethral obstruction.

The measurement of detrusor pressure and flow rate during voiding is the only way to objectively measure or grade infravesical obstruction. The resulting data cannot be interpreted easily. Manual as well as automatic methods have been introduced to derive one or several factors or parameters to quantify urethral resistance. A number of these methods are described in this overview. Since automatic methods involving computers guarantee uniform, unbiased, and objective processing of data, besides enabling the use of (statistical) methods that take into account more than one or two of the measured pressure and flow rate values, emphasis is on these methods. Some clinical results obtained with such automatic methods are discussed to illustrate the clinical value and possible impact on diagnosis and evaluation of treatment of lower urinary tract disorders.