Six-microtransducer catheter connected to computer in evaluation of urethral closure function of women.

A new instrument consisting of a six-transducer catheter, one transducer for the bladder and five transducers for urethral pressure recordings, and a computer with specific software was developed for urodynamic investigation of women. Twenty-six patients with stress urinary incontinence (SUI) and 10 continent female patients were evaluated during the single cough, the first and the fourth ones of the forced coughings in supine and standing positions. The results were compared with those obtained with the conventional two-transducer method. Negative urethral closure pressure (UCP) at stress, indicative of SUI, was present in 88 percent of the cases with the six-transducer method, and in 77 percent with the two-transducer method. The fourth cough in the standing position with the six-transducer method was most diagnostic. In SUI, the six-transducer method indicated exactly, e.g., the minimum bladder pressure needed for negative UCP and the duration of negative UCP. Patients with SUI had significantly lower UCP at rest, UCP at stress, and pressure transmission ratio (PTR) than continent women. Findings, that UCP at stress decreased and duration of negative UCP at stress increased but PTR did not change when the fourth cough was compared with the first one in SUI, suggest that factors which are responsible for the altered urodynamics during prolonged stress are anatomic rather than functional.