bluuebunny/crossref_metadata_2025 huggingface dataset:
Continence interval in elderly incontinent men
Authors: O'Donnell Pat D.
Published: March 2007

Urinary incontinence is a serious management problem among elderly patients. The care and management of chronic care patients is more difficult in those having urinary incontinence. The level of care required is dependent on both the continence and incontinence behavior of the patient. The continence behavior in this study is presented as the time interval between episodes of involuntary urine loss. The continence interval in elderly inpatient men having severe incontinence was found to be significantly longer in patients having a larger measured cystometric bladder capacity as well as in patients having greater independence in activities of daily living. Significant variability in the continence interval was measured for each patient over a wide range of continence intervals and resulted in an irregular pattern of time between episodes of incontinence. The irregular continence intervals suggest an instability of the central nervous system sensory‐motor regulatory mechanism of bladder control in the elderly.
Comparison of different methods for quantification of urinary leakage in incontinent women
Authors: Mouritsen Lone , Berild Grethe , Hertz Jens
Published: March 2007

To evaluate different methods for assessment of diagnosis and severity of urinary incontinence, 72 women underwent two consecutive 24 hours pad tests, a 1 hour pad test, a stress test, urodynamic examination, and a voiding‐cysto‐urethrography. The results were analysed and related to clinical findings.

The 24 hours pad test revealed a good patient compliance, was as informative as to grade of incontinence as a 48 hours test, was reliable for all grades and types of incontinence, and correlated to clinical findings.

The 1 hour pad test underestimated the grade of incontinence and was less correlated to clinical parameters than the 24 hours test.

To estimate a level for pathological leakage, 25 continent controls underwent a 24 hours pad test. The results of the pad tests could be stratified by mean leakage per 24 hours as follows: up to 5 g in continent women, 40 g in mild incontinence, 80 g in moderate incontinence, and 200 g in severe incontinence.

It could be concluded that a 24 hours home test was the pad test of choice for quantification and diagnosis of urinary incontinence.
Autonomic sympathetic nerve involvement in diabetic impotence
Authors: Ertekin Cumhur , Ertekin Nezihe , Almis Sait
Published: March 2007

Sympathetic skin potentials (SSP) were evoked by peripheral nerve stimulation of the hands, feet, and genital skin of 49 diabetics with erectile impotence. Eight potent diabetic men were used as controls. The bulbocavernosus reflex latency (BCR) was also recorded from all patients. The BCR was prolonged in 31% of impotent patients, while the SSP were absent in the genital skin in 47%. Fifty nine percent had either prolonged BCR or absent SSP. In 12 patients with “subacute impotence” the electrophysiological findings were abnormal in 10 (83%). In 37 patients with slowly progressive impotence, 51% had electrophysiological abnormalities.

It was concluded that pelvic‐autonomic neuropathy is one of the major contributing factors in the pathogenesis of diabetic erectile impotence, especially in the subacutely developing cases; however, neuropathic and vascular factors probably both play a part in the pathogenesis of impotence in the majority of cases with a slowly progressive course.
Detrusor instability in prostatic obstruction in relation to urethral opening pressure
Authors: Cucchi A.
Published: March 2007

Forty males with bladder outflow obstruction from benign prostatic hypertrophy (BPH)—20 with unstable bladders and 20 with stable ones—were studied. All of these patients have been assessed both clinically and urodynamically. The presence of instability was found to be associated with a higher urethral opening pressure as well as to involve important changes in voiding dynamics, i.e., an increased velocity of shortening of the contracting detrusor and, most likely, an actively increased mechanical capability of the bladder smooth muscle to generate external voiding power. It seems that the link between an increased opening pressure and the presence of instability, with the consequent changes in voiding dynamics, can be well explained 1) by the theory that obstructive detrusor instability is a denervation supersensitivity phenomenon or even 2) by a pathological urethrovesical reflex, activated by abnormal afferent stimuli from an anatomically altered prostatic urethra. Both hypotheses are discussed herein. No correlation was found between the severity of detrusor trabeculation and the presence of instability. Such a feature is believed to depend on the aforementioned increase in the muscle mechanical capability of the detrusor. This might lessen the need for bladder smooth muscle hypertrophy (as a force generator) to develop in response to infravesical obstruction and thereby even the chance for collagen fibers to be produced by hypertrophic smooth muscle cells.
Diuretics and urinary incontinence in community‐dwelling women
Authors: Fantl J. A. , Wyman J. F. , Wilson M. , Elswick R. K. , Bump R. C. , Wein A. J.
Published: March 2007

The relationship between diuretics and involuntary urine loss is poorly understood. This study presents data on 130 community‐dwelling women with urinary incontinence. Forty‐five of these women took diuretics and 85 did not. These groups were compared with regard to clinical and urodynamic characteristics and severity of urinary incontinence and of diurnal and nocturnal micturition frequency. Subjects on diuretics were heavier (P<0.01), had higher systolic blood pressure (P<0.001), and had a higher prevalence of cardiovascular disease (P<0.001) and diabetes (P<0.001). In addition, they used cardiovascular medications more often (P<0.001) and had been treated for incontinence previously more frequently (P<0.001). Urodynamic variables showed essentially no significant differences other than the volume voided during uroflowmetry, with subjects on diuretics voiding significantly smaller volumes than subject not taking such drugs (P<0.05). Those on diuretics had significantly more incontinent episodes (P<0.01) and diurnal urinary frequency (P = 0.001). In addition, those subjects on diuretics who had bladder instability lost significantly larger quantities of fluid during testing (P<0.05) and had more episodes of nocturia (P<0.01). Although some findings can be explained by an increased diuresis, others cannot. A local pharmacologic effect is thought unlikely. Changes in sensitivity threshold due to habit, or behavior is considered possible. Diuretics and/or conditions associated with their use seem to influence the severity of the syndrome of urinary incontinence.
Urodynamics in comatose patients
Authors: Wyndaele J. J.
Published: March 2007

Urodynamics were investigated in 15 patients in coma due to brain lesion. In 5 acute patients who had spontaneous micturition, cystometry showed bladder overactivity. A low‐compliance bladder with a large capacity and noncontractile detrusor was found in 5 acute patients with temporary urinary retention. In 5 patients with prolonged coma, complete bladder emptying and detrusor‐sphincter synergia was found. These findings are correlated with modern concepts of lower urinary tract neurophysiology.
Recruitment experiences in a stress incontinence clinical trial
Authors: Burns,Ph.D Patricia A. , Nochajski Thomas , Desotelle Patricia Clesse , Pranikoff Kevin
Published: March 2007

Major delays and subsequent alterations in randomized controlled clinical trials have been attributed to poor or failed recruitment. This paper presents the recruitment methods used successfully to obtain a homogenous sample of females with stress urinary incontinence. This sample was recruited to investigate the effectiveness of a behavioral treatment. Recruitment methods and their cost effectiveness are presented for the trial's three year duration. Yields are presented as ratios of recruited/randomized subjects. Analysis showed professional referrals to have the lowest cost/yield, while newspaper advertisement produced the highest recruited/subject retention. As a result of this trial's experiences recommendations were made for differing recruitment strategies according to source/yield with additional special plans for recruiting elderly, lower income, inner city, or minority subjects.
Animal study of pudendal nerve cuff electrode implants for collision block of motor activity
Authors: Sweeney J. D. , Mortimer J. T. , Bodner D. R.
Published: March 2007

Through previous acute animal studies we have developed an asymmetric two electrode cuff (ATEC) implant for collision block of orthodromic pudendal nerve motor activity. In this paper we describe preliminary results concerning the effectiveness and safety of unilateral pudendal nerve ATECs implanted for 1 month in three adult male dogs. An apparent temporary pressure block of large fiber conduction in the implanted nerve trunks produced distinctive differences between the 2‐week and 4‐week tests in all three animals. In the first two implants significant nerve trunk tissue damage due presumably to surgical trauma and/or cuff encapsulation decreased the effectiveness of ATEC function; however, with the third implant virtually no damage was detected and ATEC effectiveness was high.
Urodynamic findings in the lower urinary tract: I. Stress‐incontinent vs. ‐continent women
Authors: Van Venrooij Ger E. P. M. , Boon Tom A. , Vervest Harry A. M.
Published: March 2007

Urodynamic findings in 250 patients with objective stress incontinence were compared with those of 108 controls without abnormalities. Patients with any component of motor‐urge incontinence were discarded from the study. The results were as follows: abdominal straining to void was significantly higher in the stress‐incontinent group; urethral resistance. maximal urethral closure pressure, and the relative urethral leakage pressure was significantly lower in the stress‐incontinent group. In light of the higher incidence of inefficient voiding pallerns seen in the stress‐incontinent population, preoperative urodynamic evaluation including cystometry with pressure flow studies, is important to exclude or at least be aware of the possibility of postoperative bladder‐emptying problems—apart from the need to exclude underlying motor instability.

Relative urethral leakage pressure measurements were significantly lower than maximal urethral closure pressure measurements in stress‐incontinent patients. Urethral closure pressure profilometry is recommended in patients who are considered for retropubic urethropexy.
Urodynamic differentiation of parkinson disease and the shy drager syndrome
Authors: Berger Yitzhak , Salinas Jesus N. , Blaivas Jerry G.
Published: March 2007

The urodynamic findings of 29 patients with Parkinson disease (PD) and lower urinary tract symptoms were compared with those of nine patients with the Shy‐Drager syndrome (SD). All patients with PD had bladder contraction and normal filling pressures, and 90% had detrusor hyperreflexia. Among the patients with SD, 67% had detrusor areflexia, 33% had involuntary bladder contractions, and 45% had poor vesical compliance. In all patients with SD who had a voiding cystourethrogram, an open bladder neck at rest was demonstrated, but it was found only in those with PD who had prior prostatectomy. The electromyography of the external sphincter showed some form of lower motor neuron lesion in all patients with SD, but it was normal in 39% of PD patients and consistent with just involuntary sphincteric activity in 61%. A neurological evaluation of patients with typical and atypical Parkinsonism can assist in differentiating between these two entities.
Innovation in urodynamic testing: Report of the first fully computerized work station
Authors: Shank Reed A. , Barnes Margaret M. , Benz Steven A. , Bracken R. Bruce
Published: March 2007

We have conducted the first clinical trials on a new fully computerized urodynamic instrument on a referral population of 1,690 patients. The instrument performed the full range of urodynamic tests equivalent to that of a six‐channel strip chart recorder. The computer was found capable of recording urodynamic tracings, storing the data on computer files, and generating graphic summaries of test results. The computerized work station was found to be easy to operate, safe for patient use. accurate in reporting results, and durable in active clinical use. Computer technology is proven well adapted to urodynamic testing with both clinical and research applications.
In vivo urinary bladder function in rats following prolonged diabetic and non‐diabetic diuresis
Authors: Longhurst Penelope A. , Wein Alan J. , Levin Robert M.
Published: March 2007

Changes in urinary bladder function are present in animal models of diabetes mellitus. In vivo cystometry in diabetic rats shows a bladder with increased capacity and a raised threshold for initiation of the micturition reflex. At sacrifice, diabetic rats have bladder hypertrophy, resulting in approximately a doubling of the bladder weight.

This study was designed to characterize the effects of diabetes on micturition in the streptozotocin‐diabetic rat. For comparative purposes, two different control groups were examined: 1) age‐matched control rats and 2) age‐matched rats which were given 5% sucrose to drink. Sucrose‐fed rats consumed large volumes of fluid resulting in diuresis and bladder hypertrophy.

Fluid consumption and excretion were significantly increased in diabetic and sucrose‐drinking rats. In addition, the diabetic rats both drank and excreted more than the sucrose‐drinking rats. Control rats had twice as many micturitions during the dark cycle than during the light cycle, but the volume micturition during the dark cycle was less than one‐half the volume per micturition during the light cycle. Sucrose drinking rats had the same number of micturitions as control rats during the light cycle. but the volumes per micturition were significantly increased. During the dark cycle, the number of micturitions increased four‐fold and the volume per micturition was significantly increased compared to controls. The diabetic rats, in contrast to the two control groups, had a significant increase in the number of micturitions during the light and dark cycles. Similar to the sucrose drinking rats, the volumes excreted per micturition were significantly greater than the normal controls. The data are discussed with regard to the effects of prolonged diuresis on bladder function and hypertrophy.
Continence recovery following radical prostatectomy
Authors: O'Donnell Pat D. , Finan Barre F. , Barnett Troy , Brookover Todd
Published: March 2007

Early postoperative continence problems following radical prostatectomy may occur in some patients, but continence usually improves during the first year following the operative procedure. The objective of this study was to assess the incidence of early postoperative continence problems and to determine the subsequent continence recovery over time. In 65 patients having a radical prostatectomy, mild and moderate incontinence occurred commonly at one month and three months following surgery. but significant improvement occurred at 6 months and 1 year. While most patients who have early postoperative incontinence will have recovery of continence function during the first year, the more severe early continence problems are more likely to persist as a prolonged continence dysfunction.
Pelvic floor muscle exercise for the treatment of female stress urinary incontinence: II. Validity of vaginal pressure measurements of pelvic floor muscle strength and the necessity of supplementary methods for control of correct contraction
Authors: Bø Kari , Kvarstein Bernt , Hagen Rolf R. , Larsen Stig
Published: March 2007

The present investigation comprises three methodological studies concerning vaginal pressure measurements of pelvic floor muscle (PFM) strength. Vaginal pressure was measured by a balloon (6.7 ± 1.7 cm) connected by a catheter to a pressure transducer. The balloon was placed with the middle of the balloon 3.5 cm inside the introitus vagina.

In fourty‐seven women, mean age 44.9 years (24–64), observation of movement of the vaginal catheter during PFM contraction verified 7 inconclusive results from perineovaginal palpation and was the most valid way to distinguish between correct and incorrect PFM contraction.

Vaginal pressure rise was obtained regardless of correct or incorrect PFM contraction, showing that vaginal pressure is not specific for PFM contraction. However, as the action of the PFM is elevation, a simultaneous inward movement of the vaginal catheter is present only during correct PFM contraction.

Degree of influence of various muscle groups on vaginal pressure was investigated in 14 women using two different balloons, one having a silicone reinforcement of the tip. It was found that the median contraction value of muscles other than the PFM did not exceed contraction of PFM alone. No significant difference was observed using the two types of balloons.

In three physical therapists EMG activity of the lower m. rectus abdominis was recorded during maximal PFM contractions. A rise in EMG activity always occurred during maximal contractions even if the women actively tried to relax the abdominal muscles.

It is concluded that vaginal pressure measurement of PFM strength is valid with simultaneous observation of inward movement of the balloon catheter. Vaginal pressure rise due to simultaneous contraction of other muscles is probably not larger than pressure rise due to intended PFM contraction. Reinforced balloon tip will not change pressure recording, and rise in EMG activity of lower abdominal muscles seems unavoidable during maximal PFM contraction.
Urinary tract reconstruction: Applied urodynamics
Authors: Key D. , Wan J. , Grainger R. , McDermott T. , McGuire E. J. , Bloom D. A.
Published: March 2007

Sixty‐four patients underwent urinary reconstruction guided by urodynamic investigation. Twenty‐eight patients had myelodysplasia (MM) and 26 had spinal cord injuries (SCI). Operative outcomes were assessed by repetitive urodynamic testing.

Bladder reservoir function and detrusor contractile activity were correctly assessed in all 64 patients. Operative creation of a more adequate reservoir was required in 58 patients.

Assessment of urethral continence function was inaccurate in six instances wherein we judged urethral sphincter function adequate when, in fact, it was not. Ureteral function was judged radiographically or by furosimide renography, or Whitaker perfusion testing. In the two instances where ureteral function was in doubt, it made no difference in outcome. There was a striking resolution of ureteral radiographic abnormalities after reconstruction which we attribute to the low‐pressure reservoir.
Intra‐ and inter‐ observer variations in classification of urinary flow curve patterns
Authors: Jørgensen J. Balslev , Jensen K. M.‐E. , Klarskov P. , Bernstein Inge , Abel Ivan , Mogensen P.
Published: March 2007

To assess the validity of classification of urinary flow curve patterns, six doctors at different levels of urodynamic education were asked to classify 176 urinary flow curves. The curves had been obtained from elderly, randomly selected men without voiding problems. Five flow curve patterns were defined both graphically and in writing, and the six observers were asked to classify the 176 curves into one of the five categories.

The agreement between the six observers was calculated as a frequency, and this value was corrected for the chance agreement. Some of the observers were asked to reevaluate the curves after 3 months, and the interobserver variation was calculated.

We conclude that if of any value, the classification of urinary flow curves must be undertaken by urodynamically trained persons. In that case there is a good chance that the classification can be reproduced by any other urodynamically trained person.
Effect of alcohol on bladder function: A uroflowmetric and cystometric study
Authors: Taari Kimmo , Ruutu Mirja , Lehtonen Timo
Published: March 2007

Alcohol intake may provoke urinary retention in young persons without a previous history of obstructive urinary tract disease. The mechanism by which alcohol causes urinary retention is unknown. Ten healthy male volunteers had urodynamic studies performed before and under the influence of alcohol. Detrusor instability was found in four test persons under the influence of alcohol. The mechanisms by which alcohol may cause urinary retention are discussed.
Computer simulation of the neural control of bladder and urethra
Authors: Hosein Rasheed A. , Griffiths Derek J.
Published: March 2007

A large number of neural reflex loops may be involved in voiding and leak‐free storage of urine. The simplifying hypothesis that only very few reflexes are needed to account for most of the observed behavior has been tested by quantitative simulation of the lower urinary tract and its control system. The mechanical part of the simulation, involving detrusor contraction strength and a carefully defined urethral resistance, is based on previous work. The postulated neural control system involves two mutually inhibitory control regions, leading to a bistable (storage‐voiding) system, and reflexes driven by a single afferent signal with contributions from bladder wall tension and urethral distension. Because the control system is bistable, each of the two afferent contributions has two possible effects, so that four distinct reflexes appear to operate. Simulations, with and without these reflexes, show that this system accounts for many features of normal voiding, stop tests, and catheter voiding. The behavior is not sensitive to arithmetic details of the calculations involved. After triggering by a simulated suprapontine control signal, the voiding detrusor contraction is initially amplified by the afferent signal from the detrusor but it is sustained until the bladder is empty by the urethral afferent. Mechanical urethral obstruction causes slight residual urine. Breakdown of the mutual inhibition of the two control regions leads to detrusor instability, suggesting that this condition may sometimes have a central origin.
Assessment of detrusor contraction strength or contractility
Authors: Griffiths Derek J.
Published: March 2007

This paper is a review of the various methods that have been proposed to extract an assessment of the detrusor contraction strength or contractility from pressure/flow studies of voiding. Most of the methods are fundamentally similar, differing mainly in their degree of sophistication and ease of interpretation. Guidelines for choosing among them are suggested. Fundamental equations are given in the appendix.
Estimation of contractility parameters for the urinary bladder
Authors: van Mastrigt R.
Published: March 2007

The contractility of (urinary bladder) smooth muscle can be described in terms of a relation between its contraction force and its shortening velocity. To a sufficient degree of accuracy this relation is approximated by the hyperbolic Hill equation, originally derived for striated muscle. Allowing for a constant “curvature” of the relation, this equation is completely determined by the parameters Po (isometric pressure) and vmax (maximum contraction velocity).

Micturition results from the interaction of bladder contractility with the resistance of the urethra. If variations in urethral resistance occur, a plot of bladder wall shortening, calculated from flow rate, as a function of detrusor pressure during micturition traces part of the contractility relation. In the present study 241 micturitions out of a population of 2,073 measurements taken from a mixed group of patients, i.e., 12% of pressure‐flow studies, could thus be fitted with a Hill curve, yielding the parameters Po and vmax.

A method was developed for estimating vmax from pressure and flow measured throughout any micturition. When applied to a test population it was found that the thus estimated contraction velocity called vest correlated significantly with the “true” contraction velocity vmax (Spearman's rank correlation coefficient 0.77, significant at the 0.1% level). Vest was not significantly different in groups of obstructed versus unobstructed patients, but it was found to be significantly lower in unobstructed patients that voided with significant residual volume, indicating that this parameter is not biased by urethral resistance and represents (one aspect of) the detrusor contractility.
Contraction strength variance during pressure/flow studies
Authors: Constantinou C. E.
Published: March 2007

The parameters of bladder pressure, urine flow rate and strength of contraction (W) during voiding were evaluated in female patients with stress urinary incontinence (SUI) and compared to non‐SUI patients. The long‐term modification in these parameters produced by endoscopic bladder neck suspension (BNS) was also evaluated in the SUI patients. Comparisons were made between the direct measurements of bladder pressure and flow rate during voiding with the indirect computations of W. The parameter, W, was evaluated at the prevoiding stage, and during micturition at 20% and 80% of voided bladder volume. The maximum W attained was also computed. Analysis was based on an algorithm of calculating the single valued variable W from detrusor pressure and flow rate information that was digitized by a real time computer. Data were obtained from a total of 80 patients; 49 patients with non‐SUI having a mean age of 50 ± 16 years (mean ± SD) and 31 patients 56 ± 12 years with SUI. The pre‐operative values of W and pressure/flow parameters in the 31 patients with SUI were compared with postoperative values obtained 26 months following (BNS). The results show that SUI patients void at a significantly lower pressure than non‐SUI patients and at approximately the same flow rate. There is no statistically significant difference between SUI and non‐SUI patients in the value of W at any stage of the voiding cycle. Comparison of pre‐operative to postoperative values of these parameters also shows that BNS did not produce significant changes in contraction strength W although the direct measurements of voiding pressure significantly increased and flow significantly decreased. It is concluded that the contractility of the bladder is maintained at a preset physiological level in the presence of physiologically or surgically changing urethral impedance.
Effects of bladder volume on detrusor contractility during sacral nerve stimulation
Authors: Walter James S. , Tang Pei C. , Wheeler John S.
Published: March 2007

In spinalized dogs under Nembutal anesthesia, electrical stimulation of sacral nerves with electrodes inserted into the sacral canal induced maximal urinary bladder contractions. The amplitude of the peak vesical pressure varied with the bladder volume. Active peak pressures were highest when the bladder volume was 25 to 50 ml. Pressure declined to less than 50% of its maximum value at a bladder volume of 400 ml. In order to further describe the contractile properties of the detrusor muscle, wall tension was calculated using Laplace's law, wall stress was determined as tension per unit wall thickness, and the circumference of the vesical volume was calculated as a measure of muscle length. Active detrusor wall tension during stimulation tended to be highest at the midrange of volumes, whereas the wall stress increased linearly with increasing bladder volume. This increase in wall stress was secondary to the wall becoming thin at large volumes.
Non‐neurogenic neurogenic bladder: The relationship between intravesical pressure and the external sphincter electromyogram
Authors: Rudy Delbert C. , Woodside Jeffrey R.
Published: March 2007

We retrospectively reviewed the urodynamic studies of 14 patients: 3 males and 11 females, previously diagnosed clinically and urodynamically as having non‐neurogenic neurogenic bladder. The mean age of the patients was 10 years (range 4–24 years). We identified 3 urodynamic features in this patient population that are distinct from those seen in patients with true detrusor‐external sphincter dyssynergia: (1) quieting of the external sphincter electromyogram (EMG) immediately prior to the onset of a detrusor contraction, (2) quieting of the EMG during the upslope of a detrusor contraction, and (3) augmented EMG activity during the downslope of the detrusor contraction. Although both involve incoordinate bladder and pelvic floor/external sphincter activity, a simple cystometrogram with EMG may allow reliable differentiation between true detrusor‐external sphincter dyssynergia and non‐neurogenic neurogenic bladder.
Urethral pressure increment preceding and following bladder pressure elevation during stress episode in healthy and stress incontinent women
Authors: Thind Peter , Lose Gunnar , Jösrgensen Lisbeth , Colstrup Hans
Published: March 2007

The urethral pressure elevation preceding and following pressure elevation in the bladder during cough was studied in 30 healthy volunteers and 30 genuine stress‐incontinent women. The pressures were measured by means of a double microtip transducer catheter with the distal sensor in the bladder and the proximal sensor covered with a water‐filled balloon and placed at the bladder neck, in the high‐pressure zone, or distally in the urethra. In both groups of women a urethral pressure elevation was demonstrated before and after pressure elevation in the bladder during a cough. A urethral pressure elevation ≥ 5 cm H2O both before and after bladder pressure elevation was demonstrated in one third and one fourth of healthy and stress‐incontinent women, respectively. The initial urethral pressure rise in the mid‐ and distal urethra was statistically significantly higher in the healthy women. During abrupt coughing the initial urethral pressure rise disappeared. The pelvic floor as part of the demarcation of the abdominal cavity is positively taking part in the intraabdominal pressure generation during stress episodes, and the urethral pressure increment in advance of bladder pressure elevation reflects an active contraction. A lowering of this initial urethral pressure rise may be a contributing factor of the pathogenesis of genuine stress incontinence, although it does not necessarily result in stress incontinence.
Correlation of in vitro pressure generation with urinary bladder function
Authors: Levin Robert M. , Kato Kumiko , Lin Alex T. , Whitmore Kristene , Wein Alan J.
Published: March 2007

Urinary bladder function consists of a filling and storage phase followed by an active coordinated expulsion phase. A large part of our knowledge of bladder function, as well as bladder physiology and pharmacology, comes from a variety of in‐vivo and in‐vitro experimental animal models.

Of the in‐vitro methodologies available for the study of bladder smooth muscle, the isolated bladder smooth muscle strip techniques and isolated whole bladder techniques are two of the most popular. In general, the ability to generate pressure in the non‐emptying whole bladder model is directly related to phasic contraction of the bladder smooth muscle, and can be equated with the response of isolated strips. Although both techniques generate useful and important information, one must be very careful in making conclusions concerning bladder function based solely on contractile data.

We have studied the volume‐pressure relationship of the bladders of control rabbits and of those subjected to bladder outlet obstruction (2 week) and unilateral ischemia (2 week). For each bladder, in‐vitro cystometry, pressure generation, and the ability of the bladder to empty (in response to both bethanechol and field stimulation) was determined. Although it was clear that outlet obstruction and unilateral ischemia induced marked alterations in bladder compliance, capacity, and the ability to empty, bladder pressure generation was not significantly affected. These studies support the view that contractile studies in and of themselves cannot be used to describe the functional state of the bladder. Only through the application of several techniques including studies on bladder compliance, capacity, and the ability of the bladder to empty can the functional state of the bladder be evaluated.
Overnight vesical and rectal motility in children with vesico‐ureteral reflux
Authors: Lind M. , Rittig S. , Gregersen H. , Andersen A. J. , Knudsen U. B. , Nielsen J. B. , Djurhuus J. C.
Published: March 2007

The rectum and bladder are both innervated by the sympathetic and parasympathetic nervous system and have a close anatomical relation. In order to investigate whether a correlation between rectal and vesical activity is present we undertook the following study.

Overnight pressure recordings from the bladder and the rectum were analyzed in 35 children with vesico‐ureteral reflux (VUR). The rectal activity of the VUR patients was compared to the rectal activity of 22 overnight recordings from normal children. The measurement system included bladder pressure measurement by way of fluid‐filled supra‐pubic catheters and rectal pressure measurement by a perfused open‐side hole catheter. Thirty‐two of the thirty‐five investigations were suitable for later computer analysis. The analysis program contained facilities for automatic scoring of contractions, frequency analysis, and area under curve determinations.

Activity in the bladder and rectum was equally distributed between the reflux grades both regarding the number of contractions and the area under curve. Overnight number of contractions and the area under curve were correlated within the individual patient (σ = 0.80, P lt; 0.01). This indicates that the two variables equally reflect pressure activity. In patients with VUR rectal activity intensity were significantly correlated to bladder activity (σ = 0.53, P < 0.01). However, the number of rectal contractions in the patients were not significantly different from normals.

It is concluded that the urodynamic pressure data can be analyzed using a computer‐aided method, providing a rapid and objective analysis of the data. Night‐time monitoring seems to reveal a general coherence between bladder and rectal motility in this category of patients. The nature of the relation between bladder and colo‐rectal activity needs further elucidation.
One‐hour ward test vs. 24‐hour home pad weighing test in the diagnosis of urinary incontinence
Authors: Thind Peter , Gerstenberg Thomas C.
Published: March 2007

Twenty‐five women completed a 1‐hour pad‐weighing test and two consecutive 24‐hour home pad‐weighing tests in order to compare the 1‐hour test with the 48‐hour test and to evaluate the further information given by the 48‐hour test compared to the first 24‐hour test. The correlation between the results of the 1‐hour test and the results of the 24‐ and 48‐hour tests was low (r = 0.35 in both). The patients classified as incontinent in the 1‐hour test also had significant leakage in the 48‐hour test. The 1‐hour test had a false‐negative rate of 36% if the 48‐hour test is considered the absolute standard. The correlation between the leakage during the first 24‐hour test and the 48‐hour test was high (r = 0.96), but two patients had insignificant leakage during the first 24‐hour test and significant leakage during the 48‐hour test. The 1‐hour test is usable as a quick test in the ward, but only the demonstration of significant incontinence is reliable. The 24‐hour test predicts the state of incontinence quite precisely; however, the results seem to improve slightly by extending the test period to 48 hours.
Autoradiographic localization of α1‐adrenoceptors in the dog prostate and urethra with 3H‐prazosin
Authors: Yablonsky F. , Savasta M. , Manier M. , Poirier M. , Lacolle J. Y. , Feuerstein C.
Published: March 2007

The regional distribution of α1‐adrenoceptors in the dog urethra has been studied by quantitative autoradiography using the specific α1‐antagonist 3H‐prazosin as a ligand. The binding of 3H‐prazosin to urethral tissue sections was saturable, reversible, and of high affinity (Kd = 0.7 nM); it occurred at a single population of sites and possessed the pharmacological features of the α1‐adrenoceptor. The binding parameters of 3H‐prazosin on urethral tissue sections were found similar to those obtained on urethral membranes. Autoradiographic results revealed that the α1‐adrenoceptors are heterogeneously distributed along the dog urethral axis. The highest densities of 3H‐prazosin binding sites were found in the preprostatic urethra. Comparison between autoradiographic and histological slides revealed that the 3H‐prazosin binding sites were only localized on the smooth muscle fibres of the dog urethra.
Objective quantification of stress urinary incontinence: A short, reproducible, provocative pad‐test
Authors: Hahn I. , Fall M.
Published: March 2007

To evaluate the reproducibility, sensitivity, and accuracy of a short, provocative pad‐test designed for quantification of urine loss in stress urinary incontinence, 50 women underwent two separate, standardised tests. The tests were performed as part of the urodynamic examination at a bladder volume that is half of the cystometric capacity.

A good correlation between the two tests was found (r = 0.94). The test was found to be provocative enough to reveal even slight stress incontinence. There were no false‐negative results. The test correlated well to the patient's own assessment of urine loss and to the patient's daily symptoms. It was readily performed for the patient as well as the investigator.

This provocative test seems practical and is reliable enough for quantification of stress urine loss in scientific studies.
Urethral pressure and pressure variations in stress incontinent women and women with unstable detrusor
Authors: Sørensen S.
Published: March 2007

The urethral pressure and pressure variations were studied in ten genuine stress incontinent women and twenty‐six women with unstable detrusor based on 1 hour recordings. In the stress incontinent women the mean maximum urethral pressure (mMUP) calculated from 1 hour continuous urethral pressure recordings was 49 cm H2O and the mean maximum urethral closure pressure (mMUCP) was 38 cm H2O. When analysed in relation to previous data from healthy women the mMUP and the mMUCP were significantly reduced. The urethral pressure variation (UPV) is a normal physiological activity of the urethra, also occurring in stress incontinent and unstable detrusor patients. The UPV amplitude of the stress incontinent women was reduced, indicating that the UPVs are related to the baseline pressure in urethra but still part of the complex pathophysiological changes occurring in urethra during stress incontinence. In the unstable detrusor group the parameters were within the range of the normal material except for the abrupt urethral pressure drop followed by detrusor contraction. However, these events were clearly different from the rhythmic urethral pressure variations which seem to discern from the pathogenesis of the unstable detrusor.
Rhythmic pressure variations in urethra and anal canal: Investigations in healthy fertile female volunteers
Authors: Sørensen S. , Gregersen H. , Sørensen S. M. , Djurhuus J. C. , Constantinou C. E.
Published: March 2007

Ten healthy fertile female volunteers underwent one hour continuous urethral and anal canal pressure recordings. The recordings showed a median maximum urethral pressure (mMUP), of 74.0 cm H2O and a median maximum anal canal pressure (mMAP) of 50.0 cm H2O. The anal canal pressure variations (APV) showed the same frequency domains as found in the urethra ranging from 0.001 to 0.03 Hz. The APV amplitude was correspondingly diminished and the two pressure tracings were out of phase indicating the urethral pressure variations (UPV) and APV to be separate intrinsic spontaneous activities of the urethra and anal canal.

Twenty‐six months prior to the present study the women had a similar urethral pressure recording. Comparison of the mMUP, maximum urethral closure pressure (mMUCP), and UPV frequency and amplitude showed no difference between the two periods.

The intraindividual variation was lower than the interindividual variation meaning that the individual woman had rather stable urethral pressures, whereas there was a considerable variation between the women. The rhythmic UPV frequencies and amplitudes were stable during the two year period.

Consequently the study underlines the consistency of urethral pressure. The comparative investigations of urethral and anal pressure add evidence to our pressure statements that they originate from smooth muscle activity.
Ureteric peristalsis: An unusual finding during cystometry
Authors: Ramsay Ian N. , Hilton Paul , Ramsden Peter D.
Published: March 2007

If dual channel subtracted cystometry is to demonstrate detrusor pressure, correct placement of the catheter in the bladder is critical. Two cases of inadvertent retrograde catheterisation of the ureter during cystometry are described. In one case the patient had undergone previous ureteric reimplantation, and catheterisation occured on two occasions. In this case radiological evidence of the catheter in the distal ureter was obtained. In both patients short lived phasic contractions of 15 ∼ 20 cm H2O pressure were seen throughout the filling phase, this being compatible with previously reported patterns of ureteric activity.
The frequency/volume chart in detrusor instability
Authors: Larsson Gregor , Abrams Paul , Victor Arne
Published: March 2007

This study was done to evaluate the use of the frequency/volume chart in patients with motor urgency. Pretreatment data from a study of the effects of terodiline in women with motor urgency incontinence were used and compared with the findings of an investigation of healthy female volunteers. The relation of the values from the frequency/volume chart to cystometric data in the group of motor urgency patients were also studied. In spite of the statistically significant differences between the two groups in the parameters of the frequency/volume chart, it is concluded that the overlap between the groups limits the use of the chart for diagnostic purposes at this stage. The mean voided volume (total voided volume/frequency) is considered a reliable measure of the severity of motor urgency. No correlation was found between the data of the frequency/volume chart and cystometry. It is suggested that cystometry mainly gives a qualitative measure of motor urgency, whereas the frequency/volume chart offers objective and reliable quantitative information of the symptoms, and thus supplements the cystometric evaluation.
Effect of voluntary attention on urethral pressure
Authors: Aranda Bernard , Letzt‐Ribinik Patricia
Published: March 2007

We have systematically and simultaneously recorded vesical pressure and maximum urethral closure pressure (MUCP) in 109 women consulting for urinary incontinence over an extended period of time. During the recording, we asked them to peform a mental calculation (MC) test and other tests designed to induce an effort of voluntary attention. We found a significant increase in MUCP during the MC. At rest, 57 women displayed urethral pressure variations (UPV) higher than 15 cm H2O. MC inhibited UPV in 80% of these cases. Such variations have never yet been reported.

The effect of MC can be compared to an orienting reaction, which normally increases the sympathetic tonus. The role of the smooth and striated muscle fibers of the urethra, in the observed changes in urethral pressure, is discussed in light of the literature data.
Rapid injection cystometry and hydroxyproline content in the acutely overdistended rabbit bladder
Authors: Kim Hayoung , Belville William D. , Wedemeyer Gary , McGuire Edward J.
Published: March 2007

Bladder overdistention occurs in a variety of clinical circumstances including trauma, benign prostate hyperplasia, urethral stricture, and in the post‐operative and postpartum state. Overdistention can lead to injury and subsequent failure of the bladder contractile mechanism with loss of normal micturition. To date, there is no useful clinical test to predict which individuals will recover effective voiding function. Similarly, the ability of the bladder to tolerate a given degree of overdistention, and/or the time required to induce a permanent injury, are also unknown.

Four degrees of bladder overdistention injury (1, 2, 3, and 4 hours) were induced in a randomized rabbit model. The following day, the animals underwent rapid injection cystometry and at 10 days following injury the bladders were assayed for hydroxyproline content. The results show that the hydroxyproline level (nmol/mg) was directly related to the overdistention interval (r = 0.30803) and inversely related to the maximum height of the contraction curve (r = −0.31573).

Further, the rapid cystometry curves found were of two different types and correlated highly with hydroxyproline levels (P<.001). These contraction curve types are distinct at the maximum pressure point suggesting persistent active contractile forces. These findings suggest that the shape of the curve at the maximum pressure point may be clinically more useful than the half decay time or shape of the relaxation curve as suggested by prior work in this area.
Cause of low compliance in a guinea‐pig model of instability and low compliance
Authors: Macneil H. F. , Brading A. F. , Williams J. H.
Published: March 2007

Experiments were performed to determine whether the low compliance seen in the bladders of guinea pigs with a partial bladder outflow obstruction was due to active or passive properties of the bladder wall.

Sham‐operated and obstructed animals were assessed urodynamically 6 to 12 weeks later. Three‐quarters of the obstructed animals had developed low‐compliance bladders. In vitro cystometry was performed on the isolated bladders in a physiological saline solution. The measurements were then repeated in Ca‐free solution to abolish any contribution of smooth muscle contraction, and then in a high K, Ca‐containing solution, which initiates maximum contraction in isolated detrusor strips.

Bladder compliance was higher in the sham‐operated animals than in obstructed animals. In sham‐operated animals the compliance was decreased in the high K solution, but in the obstructed, low‐compliance bladders the compliance did not change significantly under any experimental condition, suggesting that in this latter group the low compliance was caused by passive properties of the bladder wall.

Changes in the viscosity of the bladder wall were assessed by monitoring the decline in pressure after a stepwise increase in bladder volume. No change in the viscosity of the obstructed bladder was detected.

We conclude that the low compliance in the obstructed guinea pig is probably due to a change in the elasticity of the bladder wall.
Post‐prostatectomy incontinence: Part I. The urodynamic findings in 107 Men
Authors: Leach Gary E. , Yun Scott K.
Published: March 2007

A retrospective review of 107 men referred for evaluation of post‐prostatectomy incontinence (71 post radical retropubic prostatectomy, 26 post transurethral resection of the prostate, and 10 post open prostatectomy) was conducted.

After in‐depth urodynamic studies, only 40 men (37%) were found to have sphincteric insufficiency alone, 36 men (34%) had sphincteric insufficiency combined with high pressure bladder dysfunction (detrusor instability and/or decreased compliance), and 21 men (20%) had bladder dysfunction alone as the sole cause of post‐prostatectomy incontinence. Ten patients (9%) had normal urodynamic studies.

The role of bladder dysfunction as a causative factor in post‐prostatectomy incontinence is strongly emphasized. © 1992 Wiley‐Liss, Inc.