Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “bladder outlet obstruction”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 109 records · Page 6Linked to original sources
PubMed2005

Videourodynamic characteristics and lower urinary tract symptoms of female bladder outlet obstruction.

OBJECTIVES: To analyze the lower urinary tract symptoms (LUTS) and videourodynamic characteristics of female bladder outlet obstruction (BOO). METHODS: Videourodynamic studies were performed in 207 women with signs and symptoms of BOO. Bladder outlet obstruction was defined as the radiologic evidence of bladder outlet narrowing plus a voiding pressure greater than 35 cm H2O and a maximum flow rate less than 15 mL/s or a voiding pressure greater than 40 cm H2O. Women with BOO were categorized into five groups on the basis of the videourodynamic findings. The LUTS and urodynamic parameters were analyzed according to these classifications. RESULTS: Videourodynamic study revealed bladder neck obstruction in 18 patients (8.7%), urethral sphincter obstruction in 56 (27.1%), pelvic floor muscle obstruction in 106 (51.2%), high-grade pelvic organ prolapse and BOO in 13 (6.3%), and urethral stricture in 14 (6.8%). Urgency frequency was reported by 94% and difficult urination by 57% of the total patients. Among the 17 patients with urinary retention, obstruction was noted at the urethral sphincter in 10, pelvic floor muscle in 5, bladder neck in 1, and urethral stricture in 1. Detrusor overactivity was found in 52.7% of total patients and was most frequent in those with urethral sphincter obstruction (78.6%). Patients with bladder neck obstruction had the highest voiding pressure and lowest maximum flow rate. CONCLUSIONS: Differences in videourodynamic characteristics of women with BOO might be associated with the underlying pathophysiology of the bladder, urethral, and pelvic floor muscle dysfunction.

Adolescent↗
PubMed2000

Bladder outlet obstruction nomogram for women with lower urinary tract symptomatology.

The aim of our study was to construct a bladder outlet obstruction nomogram for women with lower urinary tract symptoms. A urodynamic database of 600 consecutive women was reviewed. Bladder outlet obstruction, utilizing strict diagnostic criteria, was diagnosed in 50 (8.3%) patients. A comparison of patient characteristics, uroflowmetry, and detrusor pressure-uroflow studies was carried out between the obstructed patients (mean age, 64.4 +/- 17.6 years) and 50 age-matched unobstructed controls (mean age, 64.8 +/- 10.7 years). Maximum flow rates were significantly higher in free uroflow studies (free Qmax) than in pressure-flow studies (Qmax), in both obstructed (9.3 +/- 3.7 versus 5.7 +/- 3.6 mL/s, respectively. P = 2. 6 10(-6)) and unobstructed (25.6 +/- 11.2 versus 11.8 +/- 5.9 mL/s, respectively. P = 8.7 10(-12)) patients. Comparison of detrusor pressure at maximum flow (pdet.Qmax) and maximum detrusor pressure during voiding (pdet.max) values did not reveal significant differences, in both obstructed (39.3 +/- 18.4 versus 49.7 +/- 25.5 cm H(2)O, respectively) and unobstructed (16.5 +/- 8.4 versus 20.6 +/- 9.2 cm H(2)O, respectively) patients. Further statistical analysis was carried out to construct bladder outlet obstruction nomogram. The nomogram classifies any pair of values of free Qmax and pdet.max into one of the following four zones: no obstruction, mild obstruction, moderate obstruction, and severe obstruction. Of the 50 obstructed women, 34 (68%) were classified by the nomogram as mildly, 12 (24%) as moderately, and 4 (8%) as severely obstructed. A positive correlation was found between subjective severity of the symptoms (assessed by the AUA Symptom Index score) and the four nomogram zones. In conclusion, the nomogram makes it possible to differentiate between obstructed and unobstructed women and between various degrees of obstruction. We believe the nomogram may also serve as an instrument to assess treatment outcomes.

Adult↗
PubMed1998

Dog model for studying detrusor instability secondary to acutely induced variable bladder outlet obstruction.

BACKGROUND: Involuntary detrusor contractions often cause irritative symptoms such as urgency and incontinence. A dog model for acutely induced variable bladder outlet resistance was developed to investigate the possible role of prostatic afferent nerve fibers in the development and maintenance of detrusor instability. METHODS: Fifty-eight mongrel dogs (weight range 19.5-36.5 kg) were divided into five groups: group I (n = 11) had surgically induced bladder outlet obstruction. Group II (n = 14) had urinary obstruction and bilateral sectioning of the lowest branches of the pelvic plexus supplying the prostate. Group III (n = 10) had prostate denervation only. Groups IV (n = 10) and V (n = 13) were sham-operated and controls, respectively. In the obstructed groups (I and II), an artificial urinary sphincter (length 4.5-6.0 cm) was placed around the bladder neck and connected to a reservoir placed subcutaneously to allow postoperative adjustments of urinary resistance. All dogs were evaluated at baseline and postoperatively at 1, 3, and 6 months with uroflowmetry, postvoid residual urine volume, cystometry as well as serum creatinine, and urinalysis. RESULTS: Occurrences of detrusor instability were not associated with prostatic denervation input. The mean peak flow rates decreased significantly in the obstructed groups at all follow-ups, but did not change significantly in the nonobstructed groups. Postoperatively, the mean maximum bladder capacity was significantly decreased for groups I and II only. However, a significant correlation between maximum bladder capacity and maximum detrusor pressure could not be detected at any time point in any of the groups. Mean postvoid residual urine volume varied considerably in all groups over time. Creation of a urinary model of infravesical obstruction was associated with considerable problems. CONCLUSIONS: In our dog model of bladder outlet obstruction, prostatic sensory nerve fibers appear not to be involved in detrusor instability. Surgical induction of a constant model of bladder outlet obstruction was difficult even in a large animal. The observations from the present study raise questions about the validity of obstructive urinary animal models.

Animals↗
PubMed2003

Combination treatment with an alpha-blocker plus an anticholinergic for bladder outlet obstruction: a prospective, randomized, controlled study.

PURPOSE: We evaluate the effect of tolterodine combined with tamsulosin on quality of life in patients with bladder outlet obstruction and concomitant detrusor instability. MATERIALS AND METHODS: The study included 50 consecutive patients with urodynamically proven mild or moderate bladder outlet obstruction and concomitant detrusor instability. All patients were initially treated with 0.4 mg. tamsulosin orally once a day. A week later the patients were randomly allocated into group 1-25 who continued treatment with tamsulosin only and, group 2-25 who also received 2 mg. tolterodine orally twice daily. Reevaluation with a quality of life questionnaire and urodynamic study was performed after 3 months. RESULTS: Two patients from group 2 stopped tolterodine while 1 patient from each group stopped tamsulosin because of hypotension. Analysis revealed statistically significant improvement in quality of life scores only in group 2 patients (mean score 525.0 and 628.4 before and after treatment, respectively, 2-sided t test p = 0.0003). A significant difference was noted in both groups after treatment for maximum flow rate and volume at first contraction. Additionally, in group 2, a statistically significant difference was observed for maximum detrusor pressure and maximum unstable contraction pressure after treatment. CONCLUSIONS: Combination treatment with an alpha-blocker (tamsulosin) plus an anticholinergic (tolterodine) improves quality of life in patients with bladder outlet obstruction and concomitant detrusor instability. Interestingly, no acute urinary retention was observed and tolterodine did not affect the quality of urine flow or residual urine volume. The proposed combination appears to be an effective and relatively safe treatment option in patients with bladder outlet obstruction and detrusor instability.

Adrenergic alpha-1 Receptor Antagonists↗
PubMed2005

Efficacy of the combination of an alpha1-blocker with an anticholinergic agent in the treatment of lower urinary tract symptoms associated with bladder outlet obstruction.

The combination of an alpha1-blocker with an anticholinergic is a new and promising therapeutic approach for bladder outlet obstruction and detrusor overactivity. Both placebo-controlled and comparative studies have demonstrated that the addition of an anticholinergic in the conventional treatment of patients with bladder outlet obstruction is safe, as the likelihood of acute urinary retention is low. Although the pathophysiology of detrusor overactivity is unknown and most probably multifactorial, it is not expected that the voiding phase is influenced by regular doses of anticholinergics, although high doses may affect detrusor contraction. However, safety issues must be studied further. The combination of tamsulosin with propiverine or tolterodine, and of doxasosin with tolterodine has been shown to cause a significant improvement of lower urinary tract symptoms when compared with alpha1-blocker monotherapy. Indisputably, the existing literature provides clear evidence that the combination of an alpha1-blocker with an anticholinergic extends physicians ability to manage lower urinary tract symptoms caused by bladder outlet obstruction and overactive bladder syndrome.

Adrenergic alpha-1 Receptor Antagonists↗
PubMed1998

A comparative study of the Abrams-Griffiths nomogram and the linear passive urethral resistance relation to determine bladder outlet obstruction.

PURPOSE: The Abrams-Griffiths and linear passive urethral relationship (PURR) nomograms are commonly used to diagnose bladder outlet obstruction. To the best of our knowledge there are no clinical studies comparing these 2 evaluations to determine if they similarly predict the findings of bladder outlet obstruction. MATERIALS AND METHODS: From October 1994 through December 1996 multichannel urodynamic studies were performed in 72 men with lower urinary tract symptoms. The data from each urodynamic study were plotted on the Abrams-Griffiths and PURR nomograms. RESULTS: Using the Abrams-Griffiths nomogram 23 patients (46%) were unobstructed, 15 (21%) were equivocal for obstruction and 24 patients (33%) were obstructed. When the linear PURR nomogram was applied to the pressure-flow data in each group all unobstructed cases were categorized into grade 0 or 1 (no obstruction), equivocal into grade 2 (mild obstruction) and obstructed into grades 3 through 6 (moderate to severe obstruction). CONCLUSIONS: The Abrams-Griffiths and linear PURR nomograms are helpful and comparable clinical tools to assess lower urinary tract symptoms in men. The linear PURR nomogram not only detects the presence of bladder outlet obstruction but grades its severity, which may be helpful to monitor treatment.

Aged↗
PubMed2000

Effects of partial bladder outlet obstruction and its relief on types I and III collagen and detrusor contractility in the rat.

Bladder outlet obstruction induces a rapid hypertrophy characterized by increased bladder mass and collagen deposition. An increase in collagen is likely to reduce the contractility and compliance of bladder wall. This study was undertaken to investigate the effects of partial bladder outlet obstruction and its relief on types I and III collagen, and the relationship between detrusor contractility and collagen types. A total of 40 female rats was used for experiment and divided into one control, one obstruction, and three recovery groups. The contractility to field stimulation was recorded; total collagen and collagen concentration were quantified. The localization of types I and III collagen and the expression of pro-alpha1(I) and alpha1(III) collagen mRNA were determined by immunohistochemical staining and Northern blot hybridization, respectively. Contractile response to field stimulation was reduced after obstruction and recovered following relief. The total amount of collagen increased after obstruction and decreased after relief; however, collagen concentration decreased after obstruction and increased following relief. Contractility correlated negatively with total collagen but positively with collagen concentration. The protein deposition of types I and III collagen was localized in lamina propria and muscle bundles in all groups. The expression of types I and III collagen gene was up regulated after obstruction, but down regulated after relief. Negative correlation between contractility and gene expressions of collagen types was significant. These data suggest that the change in localization and quantity of collagen types leads to morphologic changes of bladder and can have an impact on the contractility of detrusor. Neurourol. Urodynam. 19:29-42, 2000.

Animals↗
PubMed1998

Relationships between lower urinary tract symptoms and bladder outlet obstruction: results from the ICS-"BPH" study.

Despite the lack of evidence in the literature for close relationships between lower urinary tract symptoms and bladder outlet obstruction, the majority of urologists rely on symptomatology when selecting patients for prostatic surgery. We investigated the relationships between a wide range of lower urinary tract symptoms from the ICSmale questionnaire and the results of urodynamic pressure and flow studies. We evaluated 933 patients with lower urinary tract symptoms suggestive for bladder outlet obstruction from 12 countries who participated in the ICS-"BPH" study with the ICSmale questionnaire and urodynamic pressure and flow studies. Spearman rank correlation coefficients were obtained between symptoms and measures of bladder outlet obstruction. There was little or no correlation between a wide range of symptoms and the results of free uroflowmetry and pressure and flow studies. From symptoms alone, it is not possible to diagnose bladder outlet obstruction. Pressure and flow studies and symptom profiles measure different aspects of the clinical condition that should be viewed separately in the evaluation and treatment decision of the patient presenting with lower urinary tract symptoms.

Humans↗
PubMed2003

Morphometric analysis of the collagen changes induced by subcutaneous injection of interferon-gamma after bladder outlet obstruction in the rat.

AIMS: The objective of this study was to examine the effects of interferon-gamma injection on changes in collagen content, after the creation of partial bladder outlet obstruction in the rats. METHODS: A total of 50 Sprague-Dawley female rats were subjected to partial bladder outlet obstruction by using metal rods. The rats were divided into five groups (n = 10 in each group): normal control (N), sham operation (S), bladder outlet obstruction for 4 weeks (BOO), interferon-gamma injection after sham operation (S + IFN), and interferon-gamma injection after bladder outlet obstruction (BOO + IFN). Interferon-gamma was subcutaneously injected (100,000 units per injection, LG chemical Co., Seoul, Korea) daily for 4 weeks in the injection groups, after which all rats were sacrificed. RESULTS: The collagen area percentage (collagen/collagen + muscle) in each bladder, calculated through image analysis, was 40.7 +/- 1.6% in the N, 38.2 +/- 2.0% in the S, 26.6 +/- 3.8% in the S + IFN, 19.9 +/- 2.5% in the BOO, and 12.4 +/- 2.0% in the BOO + IFN group (mean +/- standard error). The difference in the collagen area percentage between the N and S groups (P > 0.05) was not significant, but there were significant differences between the N and S + IFN groups (P < 0.05), between the S and S + IFN groups (P < 0.05), and between the BOO and BOO + IFN groups (P < 0.05). CONCLUSIONS: It appears that interferon-gamma decreases the collagen content in the obstructed rat bladder.

Animals↗
PubMed2002

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.

Adolescent↗
PubMed2000

Cystometric evaluation of bladder function in non-anesthetized mice with and without bladder outlet obstruction.

PURPOSE: To develop a model for cystometric study of bladder function in the awake mouse, and to characterize urodynamically and immunohistochemically the non-obstructed and infravesically obstructed mouse bladder. MATERIALS AND METHODS: Non-obstructed Balb/CJ mice, and mice with bladder outlet obstruction after surgical, partial ligation of the urethra underwent continuous cystometry as previously described for rats. Bladders were also investigated by immunohistochemistry. RESULTS: During the period of cystometry, reproducible micturition patterns were obtained. Marked differences in the urodynamic parameters between non-obstructed and obstructed mice were revealed. In mice subjected to urethral obstruction, micturition pressure (p <0.05), threshold pressure (p <0.05), bladder capacity (p <0.001), micturition volume (p <0.001), and residual volume (p <0.05) increased significantly. There was no difference in basal pressure or compliance between non-obstructed and obstructed mice. Non-voiding bladder activity was consistently recorded in obstructed mice; both frequency and amplitude increased significantly (p <0.01). Compared with non-obstructed bladders, obstructed bladders showed hypertrophy of the bladder wall and various degrees of "patchy denervation" of the detrusor. When tested in non-obstructed mice capsaicin, prostaglandin E2 (intravesical administration) and apomorphine (subcutaneous administration) induced bladder overactivity. CONCLUSIONS: Continuous cystometry can be reproducibly performed in awake, freely moving non-obstructed mice and mice with bladder outflow obstruction. The changes induced by infravesical obstruction in mice were similar to those previously found in rats. This model may be useful for investigations of genetically modified mice.

Animals↗
PubMed1999

Diagnosing bladder outlet obstruction in women.

PURPOSE: There are no universally accepted urodynamic criteria for diagnosing female bladder outlet obstruction. When accepted criteria for men are applied to women, the diagnosis of obstruction may often be missed, which is most likely due to differences in voiding dynamics. We propose video urodynamic criteria for diagnosing obstruction in women, and describe the urodynamic findings in those with and without obstruction. MATERIALS AND METHODS: We reviewed the charts of 331 women who underwent multichannel video urodynamics for nonneurogenic voiding dysfunction. Of these women 261 (mean age 55.8 years) had evaluable voiding pressure flow studies with simultaneous video fluoroscopy of the bladder outlet during voiding. At video urodynamics cases were classified as obstructed if there was radiographic evidence of obstruction between the bladder neck and distal urethra in the presence of a sustained detrusor contraction. Strict pressure flow criteria were not used. Maximum flow rate, detrusor pressure at maximum flow rate, post-void residual, bladder capacity and the incidence of detrusor instability were compared between obstructed and unobstructed cases. RESULTS: A total of 76 women met the criteria for obstruction (mean age 57.5 years), while 184 (mean age 55) did not. Causes of obstruction were dysfunctional voiding in 25 cases, cystocele in 21, primary bladder neck obstruction in 12, iatrogenic from incontinence surgery in 11, urethral stricture in 3, uterine prolapse in 2, urethral diverticulum in 1 and rectocele in 1. Obstructed cases had lower mean maximum flow rate (9 versus 20.2 ml. per second, p <0.0001), higher mean detrusor pressure at maximum flow rate (42.8 versus 22.1 cm. water, p <0.0001) and higher mean post-void residual (157 versus 33 ml., p <0.0001). There was no difference in bladder capacity (381 versus 347 ml.) or incidence of detrusor instability (45 versus 41%). CONCLUSIONS: Using the proposed video urodynamic criteria obstructed cases had significantly higher voiding pressures, lower flow rates and higher post-void residual than unobstructed cases, as expected. However, absolute values, especially for voiding pressure, are not as dramatic in women as in men. Pressure flow studies alone may fail to diagnose obstruction but simultaneous imaging of the bladder outlet during voiding greatly facilitates diagnosis.

Female↗
PubMed2001

[The prediction of bladder outlet obstruction with prostate volume, maximum flow rate, residual urine and the international prostate symptom score in patients with lower urinary tract symptoms].

We determined whether prostate volume (PV), maximum flow rate (Qmax), residual urine (RU) and the International Prostate Symptom Score (I-PSS) predicted bladder outlet obstruction in patients having lower urinary tract symptoms (LUTSs). The study consisted of 114 patients aged 50 years or older with LUTSs who had scores of 8 or more on the I-PSS and 2 or more for the quality of life index. All patients received transrectal ultrasonography for estimation of PV and pressure-flow study (PFS). When PFS showed an obstruction grade of 2 or more in Schäfer's p/Q diagram, the result was defined as bladder outlet obstruction. When we examined which criteria indicated that 90% of patients had bladder outlet obstruction (positive predictive value: 90%), we found that PV of 35 ml or more, Qmax of 8 ml/sec or less, RU of 110 ml or more, and I-PSS of 30 or more did so. Fifty-nine percent of patients met at least one of these criteria. The results suggested that 59% of patients with LUTSs had bladder outlet obstruction with a 90% positive predictive value based on the value of PV, Qmax, RU or I-PSS.

Aged↗
PubMed2000

Pathophysiology of lower urinary tract symptoms in aged men without bladder outlet obstruction.

OBJECTIVE: To assess the pathophysiology of lower urinary tract symptoms (LUTS) in aged men without bladder outlet obstruction in a videourodynamic study. METHODS: In a videourodynamic study of 324 consecutive men with moderate to severe LUTS suggestive for bladder outlet obstruction, 112 were found to be urodynamically nonobstructed. International prostatic symptom score (IPSS), uroflowmetry and transrectal sonography of the prostate were assessed before videourodynamic study. The pressure flow expression and the obstructive parameters were compared between the 212 obstructed and 112 nonobstructed men. RESULTS: Of the 112 nonobstructed men investigated, 25 had a normal bladder and urethral trace (22.3%), 5 had detrusor instability (4.5%), 17 had a hypersensitive bladder and a normal urethra (15.2%), 3 had detrusor underactivity and a normal urethra (2.7%), while 61 were found to have a poorly relaxed external sphincter and low detrusor contractility (54.5%). Most of the patients in the normal and hypersensitive groups had normal voiding pressure and high flow (NPHF) tracings, whereas men with detrusor underactivity or a poorly relaxed external sphincter had normal voiding pressure and low flow (NPLF) tracings. Only the maximal flow rate and voided volume were significantly higher in patients with NPHF than in patients with NPLF tracings. However, both groups showed a significantly lower IPSS, less residual urine, and a smaller transition zone index than the obstructive group. After medical treatment, 78 patients (69.6%) had satisfactorily improved, 31 patients (27.6%) remained stationary, while 3 (2.7%) worsened. CONCLUSION: Nonobstructed men with LUTS have various pathophysiologies other than benign prostatic obstruction. In this study 54.5% of these patients had poorly relaxed external sphincter on videourodynamic study. Identification of the underlying pathology can not only prevent unnecessary prostate surgery but can also enable proper medical treatment to be selected.

Aged↗
PubMed2000

The significance of the American Urological Association symptom index score in the evaluation of women with bladder outlet obstruction.

PURPOSE: The American Urological Association (AUA) symptom index was originally designed to assess the severity of lower urinary tract symptoms in men with benign prostatic hyperplasia. Data concerning the clinical application of the AUA symptom index to women are sparse. We evaluated the significance of the AUA symptom index in women with urodynamically defined bladder outlet obstruction. MATERIALS AND METHODS: From a urodynamic database of 587 consecutive women 38 (6.5%) were identified with bladder outlet obstruction, defined as a maximum flow rate of less than 12 ml. per second on repeat noninvasive uroflowmetry studies with a detrusor pressure at a maximum flow of greater than 20 cm. water on pressure flow study. All patients underwent a complete clinical and urodynamic evaluation, and completed the AUA symptom index questionnaire. Results in women with urodynamic obstruction were compared with those in 2 control groups, including women without obstruction but with sphincteric incontinence and asymptomatic healthy women. RESULTS: Mean symptom score was significantly higher in women with obstruction than in those with sphincteric incontinence or no symptoms (15.8+/-8.4 versus 10.3+/-6.4 and 2.1+/-2.7, respectively). Likewise, scores were classified as severe in 34% of women with obstruction compared with only 7% of those with sphincteric incontinence. However, no correlation was noted between symptom index scores and objective urodynamic parameters, which is similar to data already reported in male populations. CONCLUSIONS: The AUA symptom index score may be useful as a bothersomeness index in women with bladder outlet obstruction. However, subjective symptoms associated with bladder outlet obstruction are nonspecific and a complete urodynamic evaluation is essential for making the diagnosis.

Female↗
PubMed1998

Experimental bladder instability following bladder outlet obstruction in the female rat.

PURPOSE: In rats, urethral obstruction was previously shown to lead to detrusor instability, but bladder instability in conscious animals has not been well characterized. The present study was designed to describe the consequences of bladder outlet obstruction on urodynamic parameters in the conscious rat. A categorization of different types of bladder instability in conscious rats is described. MATERIALS AND METHODS: Cystometry was performed on conscious animals with chronically implanted lines. Recordings of the micturition pattern and the bladder pressure during the micturition cycle were made from normal female rats and those with instability caused by infravesical outflow obstruction. RESULTS: In control rats, the peak micturition pressure was low (45.6+/-2.5 cm. H2O) and only small pressure fluctuations occurred before or after micturition. Rats with outlet obstruction exhibited bladder hypertrophy, high micturition pressure (95.5+/-6.8 cm. H2O) as well as marked spontaneous activity throughout the micturition cycle. According to the spontaneous activity profile we identified four main patterns of abnormal micturition cycles. CONCLUSION: Urethral obstruction in rats leads to a significant increase in bladder weight and to altered micturition patterns which reveal clear similarities with features of the cystometric profiles performed in men with infravesical outflow obstruction. These modifications are not consistently correlated with an increase in bladder weight.

Animals↗
PubMed2004

Longitudinal study of men with mild symptoms of bladder outlet obstruction treated with watchful waiting for four years.

OBJECTIVES: To determine the risk of clinical progressions in men with mild lower urinary tract symptoms of bladder outlet obstruction and identify the predictors for progression in this group of men. METHODS: A total of 397 men who presented to the urology clinics with mild symptoms of bladder outlet obstruction (International Prostate Symptom Score less than 8) were analyzed in this longitudinal study conducted during a 4-year period. They began with the watchful waiting protocol and were followed up every 3 months for 48 months. Age, International Prostate Symptom Score (IPSS), divided into obstructive symptom score and irritative symptom score, serum prostate-specific antigen level, total prostate volume, transitional zone volume, urinary flow rates, and postvoid residual urine volume were documented. RESULTS: The cumulative incidence of clinical progression, defined as worsening of the IPSS with migration to the moderate symptom group (IPSS 8 to 18) or severe symptom group (IPSS 19 to 35) and an increase in IPSS of more than 2 points, was 6%, 13%, 15%, 24%, 28%, and 31% at 6, 12, 18, 24, 36, and 48 months, respectively. Nineteen patients (4.9%) developed acute urinary retention within the 48-month follow-up period. Of these 19 patients, only 2 (0.6%) required transurethral resection of the prostate. The variables of importance for disease progression in the artificial neural network analysis were, in order of statistical significance, prostate-specific antigen level, obstructive symptom score, and transitional zone volume. CONCLUSIONS: The risk for men with mild symptoms of bladder outlet obstruction to progress clinically and develop complications such as acute retention of urine is moderate. Prostate-specific antigen, obstructive symptom score, and transitional zone volume were identified as important risk factors.

Aged↗