The cutoff value of bladder voiding efficiency for predicting surgical outcomes after GreenLight HPS™ laser photoselective vaporization of the prostate

The use of bladder voiding efficiency in assessing benign prostatic enlargement

Background

The management of benign prostatic enlargement (BPE) in low resource settings poses a major challenge in Africa. The objective of the study was to investigate the accuracy of Bladder Voiding Efficiency (BVE) to assess lower Urinary Tract Symptoms (LUTS) among BPE patients in a low resource setting.

Methods

From December 2017 to March 2018, patients with benign prostatic enlargement (BPE) and Lower Urinary Tract Symptoms (LUTS) were recruited into the study. The study was a prospective cross-sectional study. Participants had the International Prostate Symptom Score (IPSS) recorded followed by evaluation of their Bladder Voiding Efficiency (BVE). The BVE was calculated as the ratio of the volume of Urine voided over total volume of Urine in the bladder at the time of the void. The data were analysed to show the Sensitivity and Specificity of BVE in symptomatic LUTS. The Pearson correlation co-efficient between IPSS and BVE was analysed.

Results

The study recruited 94 participants. The age range was 45 to 85 year. The mean age was 68.1 years. The sensitivity of BVE to detect severe LUTS was 97.97%, while the specificity of BVE to detect mild to moderate disease was 97.78%. The correlation coefficient between IPSS and BVE was negatively correlated at 0.89, and this was statistically significant (P < 0.001).

Conclusion

The Bladder Voiding Efficiency (BVE) is a highly sensitive and specific test in our population to detect LUTS. It is well correlated to the International Prostate Severity Score in this study population.

Is bladder voiding efficiency useful to evaluate voiding function in women older than 65 years?

AIMS

The aims of the study were to evaluate the reproducibility of bladder voiding efficiency (BVE) between free flow (FF) and intubated flow(IF) in old women, and to search for a relationship of this index with complaint and urodynamic diagnosis.

METHODS

Urodynamic tracings of non-neurologic women referred for investigation of various lower urinary tract symptoms (LUTS) were analyzed. Urodynamic study included one FF followed by one cystometry and IF. Post void residual volume (PVR) was measured using a Bladder-scan. Exclusion criteria were voided volume<100ml and prolapse of grade>2.

RESULTS

One hundred and ninety women met the study criteria. The mean age was 74±6 years [65-96years]. The main complaint was urinary incontinence: stress (26), urge (53) and mixed (56). Forty-four women had various complaints without incontinence. Overall BVE IF (77.6±25.8) was significantly lower than BVE FF (90.4±15.3) (P<.0001). Age sub-groups stratification led similar results. BVE IF was significantly lower than BVE FF in women with incontinence whatever the cause. Urodynamic diagnosis was posed according to the ICS/IUGA recommendations and 2 sub-groups defined according with involvement of detrusor. BVE IF was significantly lower than BVE FF for detrusor dysfunction, except for detrusor overactivity.

CONCLUSION

In this large cohort of old non-neurologic women studied urodynamically for a variety of LUTS, BVE is higher when evaluated from a FF whatever age and for complaint of urinary incontinence. In addition, a low BVE value from an IF may suggest a detrusor dysfunction.

LEVEL OF EVIDENCE

4.

Comparison of bladder voiding efficiency in women when calculated from a free flow versus an intubated flow

OBJECTIVES

To assess the reproducibility of bladder voiding efficiency (BVE, Void%) between free flow (FF) and intubated flow (IF) and to correlate BVE measurements with urinary incontinence (UI) complaints and urodynamic (UDS) findings in women.

METHODS

UDS recordings of women referred for LUTD evaluation to our UDS center were reviewed. Each file included FF at arrival, filling cystometry, and IF. Post-void residual volumes (PVR) were measured by catheterization after FF and IF. Women unable to void during the study or who expelled the catheter during IF, as well as studies with voided volume < 100 ml were excluded. Data was sub-analyzed according to 3 age categories, and UI complaints and UDS findings.

RESULTS

Over the past 3 years, 237 UDS studies for FF and IF met all criteria. There was significant difference between voided volumes (232 vs. 335 ml) and PVR (24 vs. 71 ml) respectively (P < 0.0001). For the whole population, BVE IF (79.8 ± 28.6) was significantly lower than BVE FF (90.7 ± 15.9) (P < 0.0001). A significant decrease of BVE during IF was only noted for UI. BVE IF was significantly different in women in the peri-menopause and older groups. PVR IF increased with age and was significantly higher than PVR FF for women older than 45 years (P < 0.0001).

CONCLUSIONS

BVE measurement in women has a role, but is most reliable from a FF. BVE is influenced by age and urinary incontinence complaints as well as UDS findings.

Comparative study of the maximum Watts factor and Schafer contractility grade, bladder contractility index in male patients with lower urinary tract symptoms

To investigate whether the maximum Watts factor (WF) is 1 parameter of describing detrusor contraction in male patients with lower urinary tract symptoms (LUTS).We retrospectively reviewed urodynamic data of male subjects with LUTS. Data on age, maximum flow rate (Qmax), post-void residual (PVR), detrusor pressure at maximum flow rate (PdetQmax), maximum Watts factor (WFmax), and Schafer contractility grades were collected. First, all patients were divided into 6 groups according to Schafer contractility grade. The urodynamic parameters include WFmax and bladder contractility index (BCI) were compared and analyzed among the 6 groups by using Kruskal-Wallis test statistically. The box plot of Schafer contractility grade with WFmax or BCI were plotted and analyzed. Second, the correlation scatter diagram between WFmax and BCI was plotted and analyzed. Spearman's correlation test was performed. Third, we drew the Receiver Operating Characteristic (ROC) curve and confirmed the area under the curve, the Optimal Operating Point (OOP) and corresponding sensitivity and specificity for WFmax by the reference standard of Schafer contractility grade and BCI respectively.A total of 455 men were included. The mean age of patients was 57 ± 17.9 years, ranging from 18 to 87 years. Median of WFmax increased from 5.8 W/m in very week (VW) group to 19.5 W/m in strong (ST) group, while BCI rose from 70 to 170. The box plot of Schafer contractility grade with WFmax or BCI showed that both WFmax and BCI were positively correlated with Schafer contractility grade. Kruskal-Wallis test among the 6 groups showed statistically significant difference (P <.001). The correlation scatter diagram showed that WFmax increased significantly with BCI (), the linear regression equation being Y = 3.33 + 0.07X, R2 = 0.298. Spearman's correlation test revealed that WFmax and BCI were positively correlated, with the correlation coefficient being 0.616 (P <.001). The WFmax area under ROC curve by Schafer contractility grade was 0.894 and WFmax OOP was interpreted at 11.1 W/m. In addition, the area under ROC curve by BCI was 0.802 and WFmax OOP was interpreted at 9.8 W/m.Our findings suggestted that WFmax was a good parameter of evaluating detrusor contraction as well as Schafer contractility grade and BCI, which should be widely used in clinical.