[Studies on the urophonography (1)--Basic investigation with the model of lower urinary tract].

The purpose of this study is to ascertain whether the urinary (turbulent) flow really causes the sounds during micturition in humans. For this purpose the artificial bladder and urethra, which were made of silicon rubber (3M Co. Minnesota, U.S.A.), were used. The manometric device was attached to the bladder to measure the intravesical pressure. Outside the bladder neck a prostate like protrusion surrounding the urethra was made. A microphone was attached to this protrusion to detect the sound. A recording system was also adopted. The bladder was filled with 200 ml of sterile eater. By pressurising the artificial bladder at 100 cmH2O, the water passed through the urethra. During this artificial voiding the sound detection was undertaken. At the same time uroflowmetry was also performed. It was demonstrated that sound spikes were recorded whenever water in the artificial bladder passed through the artificial urethra.