ABSTRACT
【Objective】 To investigate the predictive value of non-invasive parameters in assessing detrusor function in patients with benign prostatic hyperplasia (BPH). 【Methods】 Clinical data of 384 BPH patients to undergo surgery were enrolled and retrospectively analyzed. The patients’ age and medical history time (MHT) were recorded. The free urinary flow rate was measured and maximum flow rate (Qmax) was recorded. Post-void residual (PVR) and voiding volume (VV) were measured with Bladder Scan, and bladder voiding efficiency (BVE) was calculated. Parameters including detrusor pressure (Pdet@Qmax) and Watts factor (WFmax) were collected in invasive urodynamic examination. Patients were grouped as detrusor underactivity (DU) group and non detrusor underactivity (NDU) group according to the results of WFmax, and the factors influencing detrusor function were analyzed with Logistic regression. The optimal cut-off values were confirmed with receiver operating characteristic (ROC) curve. 【Results】 Significant differences were observed in patients’ age, MHT, Qmax, PVR, BVE, Pdet@Qmax between the DU and NDU groups. Logistic regression showed that the overall prediction accuracy was higher when MHT, Qmax and BVE were included. The model prediction formula was Y=6.020-0.451XMHT+0.554XQmax-0.074XBVE. ROC curve showed when age ≥70.5 years and MHT≥ 7.5 years, there was a greater possibility of DU. When Qmax ≥5.7 mL/s and BVE ≥75.5%, the contractile function of detrusor was normal. Model prediction formula Y≥0.72 showed that detrusor contractility was normal. 【Conclusion】 Age, MHT, Qmax and BVE have certain predictive value for assessing detrusor function in BPH patients.
ABSTRACT
Objective To study the value of the preoperative detrusor contractility to the outcome assessment of prostatectomy for benign prostatic hyperplasia (BPH).Methods A total of 109 patients with BPH were analyzed.Their ages ranged from 62 to 83 years with a mean of 71 years.All patients underwent urodynamic study to confirm a diagnosis of BOO preoperatively.Further more, their BOO was not caused by nervous, endocrine or other diseases.Pateints were divided into two groups based on maximum detrusor contractility.Group Ⅰ (n =61, BPH with maximum detrusor contractility ≥ 40 cm H2O, 1cm H2O =0.098 kPa) underwent TURP or open surgery, respectively.Group Ⅱ (n =48, BPH with maximum detrusor contractility ≤ 20 cm H2O ) underwent TURP and suprapubic punctural cystostomy simultaneously,the bladder fistula was kept open continuously for at least two weeks postoperatively.The difference in outcome between the two grous was assessed by using urodynamic parameters including maximum detrusor contractility, Qmax and residual urine at one and three months postoperatively respectively.Student's t-test was used to compare the result for normally distributed data and Wilcoxon's signed-ranks test for skewed data in this study.Results There was significant difference in preoperative maximum contractility, Qmax between group Ⅰand groupⅡ (78.4 ±37.0 cm H2O) vs (19.2 ±5.4 cm H2O)(P＜0.01), (7.6±2.2 ml/s) vs (2.5 ± 1.1 ) ml/s (P ＜ 0.05) respectively.Although there was significant difference at one month postoperatively in Qmax (17.4 ±2.9)ml/s vs (12.5 ±2.0)ml/s (P＜0.05), no significant difference was found in Qmax between the two groups after three months ( 18.3 ±2.8 ml/s) vs ( 15.2 ± 1.8)ml/s (P ＞ 0.05).Conclusions The Qmax may improve and the impaired detrusor recovered gradually after the BOO was removed.Performing an operation on patients with BOO accompanied with detrusor underactivity may be useful to recover detrusor contractility.
ABSTRACT
PURPOSE: The process of micturition is depend on the bladder contracton power and urethral resistance. The higher urethral resistance in the BPH, the greater power(W) is needed to open the urethra and keep it open during voiding. It has been known that the occurrence of unstable bladder did correlate with the degree of obstruction. Unstable detrusor will exhibit greater contraction power with more efficient voiding(evidenced by higher flow rate, less voiding time). We performed this study to define the differences of urodynamic voiding parameters including detrusor contractility between unstable and stable bladder in the BPH. MATERIALS AND METHODS: In all subjects bladder outlet obstruction was ascertained urodynamically and BPH was diagnosed by digital rectal examination and transrectal ultrasound. The patients were divided into 2 groups. Group 1 included 25 men chosen randomly among BPH patients with bladder outlet obstruction and detrusor instability. Group 2 consisted of 22 men chosen at random among BPH patients with stable obstructed bladders. For each subject a number of urodynamic parameters derived from pressure-flow study were evaluated. RESULTS: Obstructive findings were found in the pressure-flow study in the both groups. Patients ages were 64.1 in the unstable and 61.9 years old in the stable group. Peak flow rate, minimum urethral opening pressure, maximum detrusor pressure, detrusor pressure at peak flow, maximum external voiding power were 14.2ml/sec, 24.3cmH2O, 52.1cmH2O, 42.9cmH2O, 537.3mW, respectively in the unstable group and 11.6ml/sec, 17.5cmH2O, 45.3cmH2O, 34.1cmH2O, 388.2mWm in the stable group. Voiding time was shorter in the unstable group(41.9sec) than in the stable group(54.5sec). Maximum cystometric capacity was significantly greater in the stable group(434.2ml) than in the unstable group(287.5ml) (p<0.01). Maximum contraction power, peak flow detrusor power, opening contraction power were significantly greater in the unstable group(38.8+/-20.2microW/mm2, 34.0+/-18.5microW/mm2, 24.0+/-3.1microW/mm2, respectively) than in the stable group(14.2+/-7.4microW/mm2, 12.9+/-8.1microW/mm2, 11.2+/-1.6microW/mm2)(p<0.01). Voiding efficiency was significantly higher in the unstable population(68.6+/-28.9%) than in the stable one(47.5+/-31.3%)(p=0.02). There were significant positive correlations between opening contraction power with maximum detrusor pressure(r=0.45) and peak flow detrusor pressure (r=0.48) (p<0.01). CONCLUSIONS: In this study, there were more powerful micturition power and more efficient voiding in unstable bladder group. Conclusively, it seems that unstable bladder possibly works as an energy saving device thereby maintaining efficient voiding despite obstruction.