The Relationship of Pressure-Flow Parameters and Urethral Pressure in Female Patients with Lower Urinary Tract Symptoms

ABSTRACT

PURPOSE: This study aimed to evaluate the relationship between pressure-flow parameters and urethral pressure in women with lower urinary tract symptoms (LUTS). MATERIALS AND METHODS: Urodynamic traces of women with stress urinary incontinence (SUI), mixed urinary incontinence (MUI), and detrusor overactivity (DO) were retrospectively studied. The urodynamic parameters such as detrusor opening pressure (DOP), detrusor pressure at maximum flow rate (PdetQmax), maximum flow rate (Qmax), detrusor closing pressure (DCP), and maximal urethral closing pressure (MUCP) were measured and compared. The relationship between pressure-flow parameters and MUCP were evaluated as well as the differences between each urodynamic group. RESULTS: One hundred fifty-one women were investigated between June 2004 and May 2008. One hundred twenty-one (80%) women had good-quality urodynamic studies and were included in the present study. The mean age was 56 years (range, 32-77). Women with DO had higher DOP, PdetQmax, and MUCP than did women with SUI (p<0.05). Qmax was significantly greater in women with SUI than in women who had DO (p<0.05). Women with MUI had DOP, PdetQmax, and Qmax that were intermediate between women with SUI and those with DO. There was a significant positive correlation between DOP, PdetQmax, DCP, and MUCP measurements and a significant negative correlation between Qmax and MUCP measurements (p<0.01). CONCLUSIONS: Pressure-flow parameters are reliable surrogates of urethral pressure. Therefore, an accurate evaluation of the pressure-flow parameters might give important information in the assessment of urethral and detrusor function in women with LUTS. Further study is needed to confirm our results.