Login to Access Video or Poster Abstract: MP31-15
Sources of Funding: none

Introduction

Pressure flow studies (PFS) have been regarded as the gold standard for evaluating bladder function. We previously reported that radical prostatectomy (RP) restore the detrusor contractility of prostate cancer patients. However, precise changes of detrusor contraction pattern remain to be completely elucidated. The most widely used measurement of bladder contractility is the Watts factor (WF). WF was calculated throughout bladder emptying and plotted as a function of the volume of liquid in the bladder at each moment in time. Impaired bladder contraction represent not only decreased the peak of WF, but also poorly sustained contractions. From this point of view, the maximum height of the resulting curve (Wmax) and its pattern should be discussed separately. In the present study, we focused on the detrusor contraction pattern using pressure flow study parameters.

Methods

In the present study, we calculated the percentage of when reach the peak of WF (Wmax%) and Area under the curve of throughout the voiding cycle (WF-AUC) (figure). WF curves allow detrusor contraction power to be visualized throughout the entire duration of micturition. Wmax% and WF-AUC could represent the pattern of detrusor contractility. _x000D_ Thirty seven patients with clinically localized prostate cancer who were urodynamically evaluated pre and post RP. The urodynamic parameters included the maximum flow rate (Qmax), postvoid residual volume (PVR), Wmax, Wmax% and WF-AUC were examined._x000D_

Results

Qmax increased significantly after RP (13.0&[rarr]17.3 ml/min, P<0.01). PVR significantly decreased (49.6&[rarr]31.4 ml, P<0.05). Although Wmax did not changed significantly (10.5&[rarr]11.0 W/m²), Wmax% and WF-AUC was increased significantly (51.6&[rarr]80.1, P<0.01 and 7714.0&[rarr]12115.8, P<0.05). Wmax is a measure of detrusor contraction strength at a single point in time, whereas Wmax% and WF-AUC can confirm the improvement of detrusor contraction throughout micturition to assess overall detrusor contractility.

Conclusions

Our study confirmed that RP change the detrusor contractility pattern of prostate cancer patients. The measurement of Wmax% and WF-AUC provides new approach to the bladder contraction sustainability.

Funding

none