Relative bladder outlet obstruction

PURPOSE: Currently bladder outlet obstruction in males is defined by the provisional International Continence Society nomogram which is partly based on expert opinion and partly on measurements before and after transurethral prostate resection. Recently there has been some interest in the development of a similar nomogram for females. MATERIALS AND METHODS: We studied the possibility of defining bladder outlet obstruction based on a sign that it causes, namely post-void residual urine. RESULTS: The probability of relative post-void residual urine exceeding 20% of bladder capacity was modeled in males and females using 1 parameter, that is URA/w20 or the ratio of the obstruction parameter urethral resistance factor (URA)-to-the bladder contractility parameter Watts factor at 20% (w20). URA/w20 represents relative bladder outlet resistance or bladder outlet resistance normalized to bladder contractility. Above a threshold of URA/w20 = 6.8 in females and 8.2 in males a relative post-void residual exceeding 20% was noted in 90% of measurements. These thresholds may be used to define relative obstruction. The provisional International Continence Society nomogram for obstruction in males was transformed into an identical nomogram for females by equating the probabilities of post-void residual urine in each gender. The latter differed from that in men, in that the lines demarcating the zones were horizontal or flow rate independent but the intercepts were approximately the same at 20 and 40 cm. water. CONCLUSIONS: Instead of defining obstruction as an absolute level of bladder outlet resistance we suggest that it is better to define it relatively, that is as a level of bladder outlet resistance that depends on bladder contractility.     

女性膀胱颈纤维化导致膀胱出口梗阻的诊治（附22例报告）

目的报告女性膀胱颈纤维化导致膀胱出口梗阻（BOO）的诊断治疗体会。方法膀胱颈纤维化导致BOO女性病例22例，经尿流动力学及膀胱镜检确诊，均行经尿道膀胱颈部分切除术，并联合药物治疗。结果随访2～15个月，排尿情况均有改善，最大尿流率〉15mL／s，国际前列腺症状评分（IPSS）5．2±1．6。病理报告显示所有病例膀胱颈组织纤维增生，其中合并慢性炎症改变10例。结论根据临床症状、尿流动力学检查及膀胱镜检可以明确诊断膀胱颈纤维化导致的BOO，经尿道膀胱颈部分切除术可以取得良好的治疗效果。     

The treatment of female bladder outlet obstruction

Authors from the USA present a review of the treatment of BOO in the female. This topic is important, which should be of considerable help to the reader. It is covered systematically, dealing with anatomy and then therapy. There is also a meta‐analysis comparing industry‐ and non‐industry funded trials of antimuscarinic medication. This careful study shows no difference in outcomes between them, but suggests there are some shortcomings that need to be overcome.     

Noninvasive methods of diagnosing bladder outlet obstruction in men. Part 1: Nonurodynamic approach

PURPOSE: Many methods have been suggested for diagnosing bladder outlet obstruction, as defined by the gold standard of pressure flow studies. Difficulty arises when comparing completely different methods of diagnosing bladder outlet obstruction. A comprehensive review of the literature of the different methods used to diagnose bladder outlet obstruction by noninvasive means was performed with a view to allow such a comparison. MATERIALS AND METHODS: A MEDLINE search was done of the published literature covering until the end of 2004 on noninvasive methods used to diagnose bladder outlet obstruction. A direct comparison of all different methods was made using the sensitivity and specificity, positive predictive value and likelihood ratio of each test. For many of the techniques these values were calculated from the data presented in the article. RESULTS: A multitude of methods has been applied to diagnose bladder outlet obstruction. Broadly the methods were divided into nonurodynamic and noninvasive urodynamic methods. Nonurodynamic methods include symptoms, biochemical tests such as prostate specific antigen, ultrasound derived measurements such as post-void residual urine, bladder weight, prostate configuration and size, intravesical prostatic protrusion and the Doppler resistive index. Part 1 of the review explores and discusses the relative merits of the nonurodynamic based methods. CONCLUSIONS: Ultrasound derived measures such as bladder wall thickness and bladder weight offer a promising possibility of diagnosing bladder outlet obstruction noninvasively. However, further reproducibility and large accuracy studies with better methodological standards are required before they can replace pressure flow studies.     

Diagnosis of female bladder outlet obstruction and relevance of the parameter area under the curve of detrusor pressure during voiding: preliminary results

PURPOSE: The diagnosis of bladder outlet obstruction in women by pressure flow study may be difficult because there are several definitions of bladder outlet obstruction, several parameters and no standard cutoffs. We evaluated the ability of pressure flow studies to separate women into unobstructed, equivocal and obstructed groups. MATERIALS AND METHODS: In a prospective study 85 women with lower urinary tract symptoms underwent clinical evaluation, including physical examination, voiding cystourethrography, endoscopy, flow rate and post-void residual volume measurement. A pressure flow study was performed 15 days later. The pressure flow study parameters were maximum flow, post-void residual volume, detrusor pressure at maximum flow, vesical pressure at maximum flow, area under the curve of detrusor pressure during voiding and area under the curve of detrusor pressure during voiding adjusted for voided volume. After considering the clinical evaluation 2 urologists classified the patients into 3 groups, namely unobstructed, equivocal and obstructed, as the traditional classification. Linear discriminant analysis was then performed using the traditional classification and pressure flow study data. RESULTS: Mean patient age was 55 years (range 18 to 83). According to the traditional classification there were 36 unobstructed, 28 equivocal and 21 obstructed cases. Significant differences were noted in all pressure flow study parameters (analysis of variance p <0.05). Linear discriminant analysis showed that area under the curve of detrusor pressure during voiding adjusted for voided volume was the most statistically discriminating parameter. Of the cases 86%, 36% and 57% were identically categorized by the traditional and area under the curve of detrusor pressure during voiding adjusted for voided volume parameter classifications in the unobstructed, equivocal and obstructed groups, respectively. The other pressure flow study parameters showed less satisfactory results. CONCLUSIONS: Area under the curve of detrusor pressure during voiding adjusted for voided volume appears to be the most discriminating urodynamic parameter of female bladder outlet obstruction. Other studies are needed to test the reliability and validity of this new parameter.     

Application of the Blaivas-Groutz bladder outlet obstruction nomogram in women with urinary incontinence

AIMS: To test the applicability of the Blaivas-Groutz nomogram for female bladder outlet obstruction in urinary incontinent women presenting in a general gynecologic practice and to determine how the nomogram results related to the presence of obstructive symptoms according to a standardized questionnaire. METHODS: All women with complaints of urinary incontinence underwent multichannel urodynamic testing, free uroflowmetry and were asked to complete a standardized quality of life questionnaire consisting of the urogenital distress inventory (UDI). The patients were classified according to the Blaivas-Groutz nomogram. RESULTS: One hundred and nine patients were classified according to the nomogram. Thirty-three patients (30.3%) were classified as unobstructed, 63 patients (57.8%) as mildly, 12 patients (11%) as moderately, and 1 patient (0.9%) was classified as severely obstructed. Fifty patients correctly completed the UDI. There was no significant difference (P = 0.61) in the score on the domain UDI obstruction between, according to the nomogram, obstructed and unobstructed patients. Only 18% of the obstructed patients had isolated voiding symptoms suggestive of obstruction. Forty-nine percent of the obstructed patients had urgency-frequency symptoms as well as voiding symptoms suggestive of obstruction. There was no correlation (Pearson, r = -0.06, P = 0.61) between the severity of the symptoms (assessed by the UDI scale) and the degree of obstruction (the four nomogram zones). CONCLUSIONS: Application of the Blaivas-Groutz nomogram gave an unlikely high prevalence of obstruction in our patient group, which showed no correlation with symptoms when measured with the UDI.     

Noninvasive methods of diagnosing bladder outlet obstruction in men. Part 2: Noninvasive urodynamics and combination of measures

PURPOSE: Many methods have been suggested to diagnose bladder outlet obstruction, as defined by the gold standard of pressure flow studies. Difficulty arises when comparing completely different methods of diagnosing bladder outlet obstruction. A comprehensive review of the literature on the different methods used to diagnose bladder outlet obstruction by noninvasive means was performed with a view to allow such a comparison. MATERIALS AND METHODS: A MEDLINE search was done of the published literature covering until the end of 2004 on noninvasive methods, including single measure and combinations of measures, to diagnose bladder outlet obstruction. A direct comparison of all of the different methods was made using the sensitivity, specificity, likelihood ratio, and pretest and posttest probability of diagnosing bladder outlet obstruction for each test. For many techniques these values were calculated from the data presented in the article. RESULTS: A multitude of methods has been applied to diagnose bladder outlet obstruction. Broadly the methods were divided into nonurodynamic and noninvasive urodynamic methods. Nonurodynamic methods were considered in part 1 of the review. Part 2 considered noninvasive urodynamic techniques, such as uroflowmetry, the penile cuff, the condom method and Doppler urodynamics. A combination of single measures was also considered and the relative merits of these approaches were discussed. CONCLUSIONS: A combination of noninvasive urodynamics and ultrasound derived measures provide promising methods of diagnosing bladder outlet obstruction. However, pressure flow studies still remain the gold standard for assessing bladder outlet obstruction.     

The relationship of the International Prostate Symptom Score and objective parameters for diagnosing bladder outlet obstruction. Part I: when statistics fail

PURPOSE: We evaluated the International Prostate Symptom Score and correlated it with objective means of determining bladder outlet obstruction. MATERIALS AND METHODS: Beginning in May 1996, 460 men 41 to 88 years old (mean age plus or minus standard deviation 60.4 +/- 9.4) were prospectively included in this study. Symptoms were evaluated using the International Prostate Symptom Score, and digital rectal examination, outpatient cystoscopy, prostate specific antigen determination and transrectal ultrasound were done. Urodynamic evaluation included uroflowmetry, filling cystometry and pressure flow study. RESULTS: Linear regression was done to correlate scores with measurable parameters. We noted no correlation of the total, obstructive symptoms or irritative symptoms score with objective parameters, including the average and maximum flow rate, post-void residual urine, prostate size and Sch?fer grade. CONCLUSIONS: Prostatic symptom scores are qualitative. Using them to quantify the degree of obstruction or evaluate therapy is questionable.     

经尿道膀胱颈内切开术治疗女性膀胱颈梗阻的疗效观察

目的:评估经尿道膀胱颈内切开术治疗女性原发性膀胱颈梗阻(PBNO)的长期疗效。方法:56例女性患者通过排泄性膀胱尿道造影及尿动力学检查确诊为PBNO,在膀胱颈上选取2点及10点位置,所有患者行经尿道膀胱颈内切开术。结果:术后随访6~72个月(平均26.2个月)。56例接受手术的患者中47例(83.9%)术后恢复良好,未见严重并发症。随访过程中,平均国际前列腺症状评分(IPSS)由21.2降至7.6(P<0.05),生活质量评分(QOL)由4.2降至2.3(P<0.05),最大尿流率(Q_max)由8.63ml/s增至17.36ml/s(P<0.05),残余尿量(PVR)由106.32ml降至21.46ml(P<0.05),最大尿流率时逼尿肌压力(Pdet at Q_max)由68.42cmH_2O降至19.86cmH_2O(1cmH_2O=0.098kPa,P<0.05)。术后出现的并发症有血尿、二次行膀胱颈内切开术、压力性尿失禁、尿道狭窄。所有这些并发症按Clavien分类评估为Ⅲa级。3例(5.3%)术后出现出血,经延长尿管留置时间、膀胱冲洗治愈,均未输血治疗;4例(7.1%)出现压力性尿失禁,行经阴道无张力尿道中段吊带术后恢复;4例(7.1%)出现尿道狭窄,间断尿道扩张后好转。结论:PBNO不常见,排泄性膀胱尿道造影及尿动力学检查可确诊,通过经尿道膀胱颈内切开术治疗安全有效。在膀胱颈的2点和10点方向仔细地、足够深度地行颈内切开可以保证手术的成功。     

经超声逼尿肌厚度测定在无创诊断女性膀胱出口梗阻中的应用

目的 探讨经超声逼尿肌厚度测定在女性膀胱出口梗阻诊断中的应用价值.方法 93例伴有LUTS的女性患者,行压力流率测定过程中,当膀胱容量为250 ml或最大膀胱容量的50％时,应用7.5 MHz高频线纵超声探头测定膀胱前壁逼尿肌厚度.以Qmax≤12 ml/s以及最大尿流率时逼尿肌压力≥25 cm H2O(1 cm H2O =0.098 kPa)作为诊断女性膀胱出口梗阻的标准,将患者分为梗阻及非梗阻两组,比较两组年龄、尿动力学参数及逼尿肌厚度的差异.应用相对工作特征曲线评价逼尿肌厚度测定作为诊断工具的价值. 结果 梗阻组42例,非梗阻组51例.两组年龄分别为(61.2±8.3)、(59.9±7.7)岁(P=0.44),最大膀胱灌注容量分别为(292.2±82.3)、(308.1±87.5)ml(P =0.37),组间比较差异均无统计学意义;两组最大逼尿肌压力[(43.1±11.2)、(16.2±7.1)cm H2O,P=0.00]、最大尿流率时逼尿肌压力[(34.3±8.2)、(13.1±7.8)cm H2O,P=0.00]、Qmax[(7.4±3.2)、(17.4±4.1)ml/s,P=0.00]、排尿量[(157.1±63.7)、(251.2±77.4)ml,P=0.00]、残余尿量[(117.5±71.3)、(37.7±18.1)ml,P=0.00]及逼尿肌厚度[(1.8±0.3)、(1.4±0.2)mm,P =0.00]比较差异均有统计学意义.当临界值≥1.9 mm时,特异性和阳性预测值均为100％,敏感性为38％,阴性预测值为62％.其曲线下面积为0.88±0.06. 结论 经超声逼尿肌厚度测定诊断女性膀胱出口梗阻具有无创、方便、可靠的特点.当临界值≥1.9 mm时,具有较高的特异度和阳性预测值,在一定程度上可取代压力流率测定.     

Suture causing urethral meatus stricture: A novel animal model of partial bladder outlet obstruction

Aims

Open surgery is the most commonly used methodological approach for generating a partial bladder outlet obstruction (pBOO) animal model. Surgical suturing closing a part of the urethral meatus induces comparable pathophysiological changes in bladder and renal functions, but the optimum degree of obstruction that closely mimics the clinical pathology of pBOO has not been elucidated. We investigated the optimum obstruction level by performing a comprehensive time‐dependent analysis of the stability and reliability of this novel animal model.

Methods

Six‐ to eight‐week‐old female BALB/c mice were divided into three groups according to the degree of urethral meatus stricture (UMS). Non‐operated mice served as controls, and a pBOO model generated using the traditional method served as a positive control. A cystometric evaluation and long‐term studies were performed to evaluate the validity and reliability of this novel animal model. An additional 35 mice were used to investigate the protein expression levels and histopathological features 24 h and 14 days postoperatively, respectively.

Results

The characteristic cystometry features in the UMS group revealed increased changes in pressure‐related parameters compared with the control. The 1/3 UMS model is an optional pBOO animal model because the cystometric evaluation and histopathological studies revealed a striking resemblance between the 1/3 UMS model and the model generated using the traditional open‐surgery method.

Conclusions

The minimally invasive UMS model required less time and produced minimal alterations in pathophysiologically relevant processes compared with the traditional surgery model. Suturing to cause UMS produced effective and repeatable patterns in bladder function investigations in mice.     

慢性前列腺炎与膀胱出口梗阻的临床观察

目的探讨膀胱出口梗阻在慢性前列腺炎诊治中的作用。方法对临床诊断为慢性前列腺炎并伴有排尿症状的患者138例,进行尿流动力学检查,统计膀胱出口梗阻的发生率;对有膀胱出口梗阻的慢性前列腺炎患者随机分为两组治疗(1)一般治疗组(A组);(2)针对膀胱出口梗阻药物治疗组(B组)。比较两组临床症状和尿流动力学检查结果的变化和治疗效果。结果138例患者中,膀胱出口梗阻106例,占76.8%。针对膀胱出口梗阻药物治疗组治疗有效44例,占83%;尿流动力学检查膀胱出口梗阻解除者40例,占75.5%。与对照组比较,差异有显著性意义。结论慢性前列腺炎伴有排尿症状的患者中膀胱出口梗阻发生率高,可能是该病的病理生理改变的一个重要方面和环节;α-受体阻滞剂和镇静剂应用是目前较有效的治疗方法。     

多沙唑嗪对兔膀胱出口部分梗阻致膀胱顺应性减低的影响

目的 探讨多沙唑嗪对兔膀胱出口部分梗阻后膀胱顺应性改变的影响.方法 成年雄性新西兰兔40只随机分为4组,每组10只,A组为假手术对照组,B组为膀胱出口部分梗阻组,C组为膀胱出口部分梗阻后口服多沙唑嗪组,D组为假手术后给予多沙唑嗪组.各组于14周行尿动力学检测,检测完成后处死并留取膀胱标本,行膀胱称重.结果 4组膀胱标本质量分别为(3.2±0.9)、(14.1±2.3)、(5.0±2.0)、(2.9±0.5)g;B、C组均高于A、D组,B组高于C组,差异均有统计学意义(P＜0.01);A、D组间比较差异无统计学意义(P＞0.05).4组逼尿肌漏尿点压分别为(10.2±2.5)、(18.8±6.1)、(13.5±4.7)、(11.6±3.6)cm H2O(1 cm H2O=0.098 kPa),B组高于A、D组,差异有统计学意义(P＜0.01),且高于C组,差异有统计学意义(P＜0.05);A、C、D组间差异无统计学意义(P＞0.05).膀胱顺应性分别为(2.86±0.56)、(1.22±0.39)、(4.25±2.19)、(2.90±0.53)ml/cm H2O,B组与A、D组相比明显下降,差异有统计学意义(P＜0.01);C组高于A、D组,差异有统计学意义(P＜0.05);A、D组间差异无统计学意义(P＞0.05).结论膀胱出口部分梗阻后早期应用多沙唑嗪治疗能够延迟梗阻对膀胱顺应性的损害,保护膀胱储尿功能.

Abstract：

Objective To explore the effect of doxazosin on rabbit bladder compliance after partial bladder outlet obstruction. Methods A total of 40 male New Zealand white rabbits were randomized into 4 groups, with 10 rabbits in each group. Partial bladder outlet obstruction was established in groups B and C, while groups A and D underwent the same operation but without partial bladder outlet obstruction. On the day after the operation, groups C and D received oral administration of doxazosin. After 14 weeks, urodynamic examinations were carried out in all groups, and the bladder was weighted after cystectomy. Results Bladder weight was (3.2±0.9) g in group A, (14.1±2.3) g in group B, (5.0±2.0) in group C,and (2.9±0.5) g in group D. The bladder weight in groups B and C increased significantly compared to groups A and D (P＜0.01), group B increased significantly over group C (P＜0.01), and there was no significant difference between groups A and D (P＞0.05).The detrusor leak point pressure was (10.2±2.5) cm H2O in group A, (18.8±6.1) cm H2O in group B, (13.5±4.7) cm H2O in group C,and (11.6±3.6) cm H2O in group D. The detrusor leak point pressure in group B was significantly higher than group A, group D (P＜0.01) and group C (P＜0.05). There was no significant difference between group A, group C and group D (P＞0.05). The bladder compliance was (2.86±0.56) ml/cm H2O in group A, (1.22±0.39) ml/cm H2O in group B, (4.25±2.19) ml/cm H2O in group C,and (2.90±0.53) ml/cm H2O in group D. The bladder compliance was significantly decreased in group B compared to groups A and D (P＜0.01). Bladder compliance in group C was significantly higher than in groups A and D (P＜0.05), and there was no significant difference between group A and group D (P＞0.05). Conclusion Early use of doxazosin can delay the occurrence of lower bladder compliance after partial bladder outlet obstruction, thus protecting the storage function of bladder.     

膀胱出口部分梗阻大鼠膀胱超微结构和尿流动力学的关系

目的观察大鼠膀胱出口部分梗阻(PBOO)后尿流动力学及超微结构变化,探讨膀胱出口部分梗阻后超微结构和尿流动力学改变的关系。方法 48只雌性Sprague-Dawley大鼠随机分为假手术组(Sham组)24只、PBOO 2周组8只、4周组8只、8周组8只。饲养后,于相应周数解剖膀胱,测定膀胱重量、不稳定收缩发生率、容量、漏尿点压及膀胱顺应性,观察逼尿肌超微结构改变等指标。结果 PBOO 2周、4周、8周膀胱重量分别为(220±24.2)mg、(327.8±27.7)mg、(521.6±24.7)mg,Sham组为(108.5±6.3)mg(P0.05);不稳定收缩发生率分别为50%(4/8)、87.5%(7/8)、37.5%(3/8),Sham组0%为(0/24)(P0.05);膀胱最大容积分别为(0.65±0.26)mL、(1.57±0.70)mL、(5.62±1.39)mL,Sham组为(0.30±0.08)mL(P0.05)。梗阻组漏尿点压为2周组(31.5±4.78)cmH2O、4周组(56.5±7.46)cmH2O、8周组(33.00±9.92)cmH2O,Sham组(22.13±3.18)cmH2O(P0.05)。膀胱顺应性PBOO 2周组、4周组与Sham组比较,差异无统计学意义(P0.05),8周组与Sham组相比,差异有统计学意义(P0.05)。透射电镜观察结果为大鼠PBOO后线粒体增多、水肿,细胞膜穴样凹陷增多,中间连接减少、缝隙连接及胞突连接增多。结论膀胱出口部分梗阻后由代偿期进入失代偿期,可以通过尿流动力学进行检测,而产生这一系列变化的形态学基础可能是超微结构的改变。     

Effect of chronic bladder outlet obstruction on blood flow of the rabbit bladder

PURPOSE: Previous studies have shown that the initial reaction of the rabbit bladder to partial bladder outlet obstruction is increased blood flow at day 1 and a return to baseline blood flow at 1 week. Mucosal and muscle blood flow followed this pattern but mucosal blood flow was always 4 to 5-fold greater. In this study we examined the effect of 4 weeks of outlet obstruction on bladder blood flow and correlated it with the severity of bladder contractile dysfunction. MATERIALS AND METHODS: A total of 14 male New Zealand White rabbits underwent partial outlet obstruction creation by standard methods. After 4 weeks the rabbits were anesthetized, and blood flow to the muscle and mucosa was determined by standard fluorescent microsphere technique. A section of each detrusor was used for in vitro contractility studies. Contractile responses to field stimulation, carbachol and potassium chloride were determined. A section of each detrusor tissue was fixed in formalin and used to determine the smooth muscle volume fraction. RESULTS: Four weeks of partial bladder outlet obstruction caused a significant and variable increase in bladder weight and a decrease in blood flow to bladder muscle without changes in the blood flow to mucosa. There was a clear correlation between the severity of contractile dysfunction, bladder weight and the magnitude of the decrease in blood flow in muscle. The smooth muscle volume fraction remained stable at approximately 40%. CONCLUSIONS: Bladder decompensation was associated with decreased blood flow to bladder smooth muscle. Because compensated obstructed bladders with relatively normal contractile function are also hypertrophied but have normal blood flow, decreased blood flow in decompensated bladders is not simply a response to bladder hypertrophy. From this study we hypothesize that decreased blood flow to bladder smooth muscle is an etiological factor in bladder contractile dysfunction (bladder decompensation) secondary to partial outlet obstruction.     

女性膀胱颈梗阻的诊断与治疗

目的：探讨女性膀胱颈阻的诊断和治疗方法。方法;对２７例女性膀胱颈梗阻患者行尿流动力学检查和膀胱检查,对其中２２例行经光颈电切术（ＴＵＲＢｎ）５例行非选手治疗。结果：２２例行ＴＵＲＢＮ治疗者术后无明显乘余尿,２０例临床症状消失;５例非手术治疗者经定期饔主药物治疗,效果满意。结论：女性膀胱颈梗阻的尿流动客观评价排尿状况的有效指标;ＴＵＴＢＮ是治疗女性膀胱劲梗阻的首选方法,具有手术小和住院时间短等优点。