Comparison of indices allowing an evaluation of detrusor contractility in women

Abstract

Aims: To compare 3 detrusor contractility indices, projected isovolumetric pressure (PIP-BCI), PIP1, and k from the VBN mathematical model, for women referred for evaluation of various lower urinary tract symptoms (LUTS) in relationship to age, presenting complaint and urodynamic diagnosis.

Methods: Urodynamic tracings of non-neurologic women were analyzed. Three indices of detrusor contractility were measured from the pressure-flow study. Exclusion criteria were voided volume<100mL, stage>2 prolapse, interrupted flow, abdominal straining. Age sub-groups were pre-, peri- and post-menopause. Urodynamic diagnosis included incontinence findings and detrusor activity during voiding.

Results: Main complaint was incontinence (354 women); 95 women (Other) had non-incontinence LUTS. PIP-BCI, PIP1 and k decreased significantly with ageing in each sub-group. PIP-BCI was significantly different between MUI and Other (P=.0259) while PIP1 was significantly higher in UUI vs. Other (P=.0161) and k in UUI vs. SUI (P=.0107), MUI (P=.0010) and Other (P=.0224). Low value of PIP-BCI for bladder outlet obstruction vs. detrusor overactivity while PIP1 and k values were high and similar for these two diagnoses and a high value of PIP-BCI for detrusor overactivity with impaired contractility close to the value for bladder outlet obstruction while PIP1 and k were low.

Conclusion: Evaluation of detrusor contractility in women is easily obtained using indices PIP-BCI and PIP1 or using the VBN nomogram giving indice-parameter k. PIP1 and parameter k produced comparable and consistent results with the urodynamic diagnosis while PIP-BCI leads to inconsistencies.

Level of evidence: 4.

Keywords: Contractilité du détrusor; Detrusor contractility indices; Femme; Index de contractilité; Urodynamics; Urodynamique; Woman.