Evaluation of bladder capacity in Korean children younger than 24 months: a nationwide multicenter study

Purpose

Bladder capacity is an important factor in the diagnosis and treatment of children with voiding dysfunction. The purpose of this study was to define the normal maximal voided volume formula in Korean children younger than 2 years.

Methods

We measured the bladder capacities of 151 Korean children between 0 and 24 months of age (83 boys and 68 girls) who did not have clinical voiding dysfunction. The maximal voided volume was determined in all subjects using a 2-day frequency volume chart with a four-hour voiding observation. The largest voided volume for each patient was considered to be the maximal voided volume. Statistical analyses were carried out using linear regression analysis.

Results

The maximal voided volume increased with age and weight (P = 0.0001). There was no significant difference between males and females (P = 0.771). A formula that approximates bladder capacity with respect to age is the following: bladder capacity (ml) = [1.6 × age (months)] + 45 (t = 8.757, P = 0.0001). A formula that approximates bladder capacity with respect to weight is the following: bladder capacity (ml) = [4.1 × weight (kg)] + 28 (t = 10.152, P = 0.0001).

Conclusions

These formulas may be useful for the diagnosis of abnormal bladder capacity and the evaluation of voiding dysfunction in Korean children younger than 24 months.     

Maximum and average urine flow rates in normal male and female populations--the Liverpool nomograms

The study of voiding in men and women has been handicapped by the lack of a normal reference range covering urinary flow rates over a wide range of voided volumes. Normal volunteers (331 males and 249 females) were studied. Each voided once into a calibrated Dantec Urodyn 1000 mictiograph. On a second occasion 282 men and 46 women voided. The maximum and average urine flow rates of the first voids in both sexes were compared with the respective voided volumes. Nomogram charts, in centile form, for both the maximum and average urine flow rates were constructed using statistical transformations of the data. Males showed a significant decline in both urinary flow rates with age, although there was no statistically significant variation in either urine flow rate with respect to first versus repeated voiding. Females showed no statistically significant variation in either urine flow rate with respect to age, parity or first versus repeated voiding. The maximum and average urine flow rates in both sexes showed an equally strong relationship to voided volume. No artificial restriction of voided volume, e.g. minimum 200 ml, appeared appropriate. These nomograms offer reference ranges for both maximum and average urinary flow rates in both sexes covering a wide range of voided volumes (15-600 ml).     

Neonatal Estrogenization of the Male Mouse Results in Urethral Dysfunction

Purpose

Analysis of voiding pattern, urodynamic measurements and immunohistochemical methods were performed in order to evaluate the effects of neonatal estrogenization on voiding functions of adult male mice.

Materials and Methods

Metabolic cages were used for recording the voiding volumes and frequencies. Bladder pressure and mean flow during voiding were measured in transvesical cystometry. Location of estrogen receptors and organization of smooth muscles in lower urinary track were demonstrated using immunohistochemical staining.

Results

Neonatally estrogenized (neoDES) male mice had lower voided urine volumes (the average voided urine volume and average of the three largest volumes) and higher voiding frequencies than control mice. In transvesical cystometry, the maximum bladder pressure during the high-frequency oscillation phase of voiding was significantly elevated. The average urinary flow rate was decreased.

Conclusions

Urodynamically, these findings are consistent with the concept that neonatally estrogenized mice have infravesical obstruction. The predominance of estrogen receptors in the periurethral region and changes in urethral smooth muscle cells immunocytochemically stained with alpha-actin-antibody support the concept of urethral wall musculature as a target of estrogen action.     

FOUR-HOUR VOIDING OBSERVATION IN YOUNG BOYS WITH POSTERIOR URETHRAL VALVES

Purpose

We evaluated 4-hour voiding observation as a method of basic assessment of bladder dysfunction in young boys with posterior urethral valves.

Materials and Methods

Voiding pattern, including number of voids, voided and residual urine volume, and bladder capacity, was determined noninvasively in 24 boys younger than 4 years with posterior urethral valves and compared to that of healthy age matched controls. Results were then compared to those of standard cystometry.

Results

The number of voids was higher, voided was smaller and residual urine volume was higher in the posterior urethral valve group. There was no difference in voiding pattern before and after removal of the anatomical obstruction. Voided and residual urine volume, and bladder capacity were higher on standard cystometry than on voiding observation.

Conclusions

Four-hour voiding observation is an easy noninvasive method that focuses on emptying difficulties and clearly detects differences in voiding patterns between boys with posterior urethral valves and healthy, nontoilet trained children. We recommend the method as a complement to standard cystometry for the diagnosis and followup of bladder dysfunction in young boys with posterior urethral valves to identify the need for treatment.     

Therapie der überaktiven Blase mit Propiverin ER

Background

The aim of this non-interventional study was to evaluate the efficacy and tolerability of propiverine ER under real life conditions.

Patients and methods

The treatment of 5,565 patients with urge urinary incontinence, urgency or mixed urinary incontinence was documented over a 12-week period. Incontinence episodes, voiding frequency and voided volume were recorded at 3 visits (admission, after 4 and 12 weeks). Additionally the tolerability was evaluated at visits 2 and 3.

Results

The average incontinence episodes/24 h decreased during therapy from 4.23 to 2.89. The frequency of micturitions/24 h decreased by 5.50. The voided volume improved by 69 ml. Approximately 92 % of investigators and patients assessed the efficacy similarly with ?very good“ and ?good”. Dry mouth was the most frequent adverse drug reaction and decreased from 16.5 % after 4 weeks to 13.6 % after 12 weeks of treatment.

Conclusion

The efficacy and tolerability of propiverine ER were confirmed under real life conditions.     

Clinical evaluation of patients with prostatic obstruction: correlation of flow rates with voided, residual or total bladder volume

Previous investigators reported that accurate estimation of average or maximum urinary flow rates required correlation with total bladder volume (voided plus residual volumes). To test this requirement we performed uroflowmetry studies on 124 patients before and 77 patients after prostatectomy. Of the patients 20 were tested on multiple preoperative and postoperative occasions to comprise paired observations. Observations were made on age, voided and residual volumes, voiding duration, and average, maximum and adjusted maximum flow rates. Prostatectomy resulted in significant increases in all flow rates and significant decreases in voiding duration. The procedure had significant effects on reducing residual volume but voided volumes increased and total volume decreased only slightly postoperatively. Preoperative average, maximum and adjusted peak urinary flow rates correlated negatively with residual volume (increasing residual volume correlates with decreasing flow rate). Maximum flow rates correlated positively with voided volume. Whether measured preoperatively or postoperatively no significant correlation was found among average, peak or adjusted flow rates and total bladder volume. The only consistent significant correlation found among voided, residual and total volumes, and other measurements was voiding duration, which increased as any of the aforementioned volumes increased. Comparison of the random total and paired populations revealed no significant difference. Use of voided rather than total volume seems preferred in correlations with maximum urinary flow rates. Determination of residual urine remains necessary as an estimation of emptying failure but it is not required information for determination of flow rates.     

Transurethral holmium laser intravesical tape excision following TVT procedure: results from seven patients in a 12-month follow-up

Introduction and hypothesis

The aim of this study is to evaluate the efficacy and the safety of the holmium:YAG laser for intravesical mesh excision in female patients with urinary bladder erosion complicated tension-free vaginal tape (TVT) procedure.

Methods

Between June 2, 2008 and December 31, 2009, seven patients who underwent laser excision of an intravesically protruding tape were followed up every 3?months for a total period of 1?year by disease-specific questionnaires, physical examination, cough stress test, urine analysis, urine bacterial culture, ultrasound and uroflowmetry. Filling cystometry was offered preoperatively and at the 3rd month, while cystoscopy was offered preoperatively and at the 1st month. The presenting symptoms were dysuria, urgency, hematuria, and recurrent lower urinary tract infections. Holmium laser was used for ablation and removal of the tape. The postoperative period was uneventful.

Results

There was a substantial improvement in the urgency status, in the maximum flow rate (Q _max) from 11.29?ml/s to 19.43?ml/s, in the voided volume (VV) from 185?ml to 251.43?ml and in the maximum cystometric capacity (C) from 237.86?ml to 310.64?ml pre- and postoperative, respectively.

Conclusions

Holmium laser ablation represents a simple, safe and efficacious procedure to manage intravesical mesh complications following TVT procedure.     

Funktionelle Ergebnisse nach Laservaporisation der Prostata mit dem KTP-Laser

Background

Treatment for bladder outlet obstruction (BOO) caused by benign prostatic hyperplasia (BPH) impairs the quality of life. The potassium tintanyl phosphate (KTP) vaporisation of the prostate offers promising modalities in treatment of BOO. We prospectively determined the impact of KTP-lasertherapy on voiding function, quality of life and sexual function.

Patients and methods

So far a total of n=123 patients complaining of syptomatic BPH were treated with an 80 watt Laser. N= 40 of them agreed to participate in the study and were evaluated prospectively. Preoperative pressure-flow-studies verified significant bladder outlet obstruction in all cases. Disease specific quality of life and sexual function were assessed using the International Prostate Symptom Score (IPSS) and International Inventory of Erectile Function (IIEF). Three months after treatment follow-up video-urodynamics were carried out to determine changements in pressure flow and bladder function.

Results

All patients showed significant improvement after a hospital stay of 4,9 days. The maximum flow rate increased from 9,1 ml/sec preoperatively to 20,2 ml/sec and the amount of residual urine decreased from 98 ml preoperatively to 17 ml immediately after removal of the catheter. Urodynamics after the follow up period showed that the maximum urinary flow improved from 9.7 ml/s preoperatively to 17,6 ml/s and the volume of residual urine decreased from a median of 127.5 ml preoperatively to 45ml postoperatively. The IPSS and IIEF decreased from a median of 20,4 preoperatively to 8,16 and from a median of 14 preoperatively to 12,7 respectively. The pressure-flow study verified the desobstruction and showed a decline in detrusor pressure at maximum flow from 76,66 cm H₂O to 33,79 cm H₂O. The urethral opening pressure sank from 75.86 cm H₂O preoperatively to 37,51 cm H₂O postoperatively.

Conclusion

The potassium tintanyl phosphate (KTP) vaporisation of the prostate is a promising new method in the treatment of benign prostatic hyperplasia as shown by the data. Beside its low perioperativ and postoperative morbidity due to a high hemostatic property it offers a good tissue debulking effect.     

Fluid intake and voiding parameters in asymptomatic Turkish women

Introduction and hypothesis

For an accurate evaluation of bladder diaries, we aim to investigate normal urinary habits and determining factors on functional bladder capacity, frequency, and 24-h volume in the bladder diaries of asymptomatic women.

Methods

One-hundred and fifteen asymptomatic women who recorded a 24-h bladder diary were included in the study. Linear regression analyses were used to explore associations between diary values and patient characteristics.

Results

Total number of voids was related to age, body mass index, total voided volume, total fluid intake, total diuresis rate, and maximum fluid intake in one go. Maximum, average, and minimum volumes per void were found to be related to body mass index, total voided volume, total fluid intake, total diuresis rate, and maximum fluid intake. When we used multiple regression analysis, only maximum fluid intake was found to be related to the total number of voids, maximum, average, and minimum volumes per void.

Conclusions

Maximum fluid intake rather than total voided volume seems to be an important determinant factor for total number of voids and functional bladder capacity.     

Femur neck bone mineral density and fracture risk by age,sex, and race or Hispanic origin in older US adults from NHANES III

Summary

We provide the first reference values for bone mineral content and bone mineral density according to age and sex in Iranian children and adolescents. The prevalence of hypovitaminosis D was high, and levels of physical activity were low in our sample. Multiple regression analyses showed age, BMI, and Tanner stage to be the main indicators of bone mineral apparent density.

Purpose

Normal bone structure is formed in childhood and adolescence. The potential determinants which interact with genetic factors to influence bone density include gender, nutritional, lifestyle, and hormonal factors. This study aimed to evaluate bone mineral content (BMC) and the bone mineral density (BMD) and factors that may interfere with it in Iranian children.

Methods

In this cross-sectional study, 476 healthy Iranian children and adolescents (235 girls and 241 boys) aged 9–18 years old participated. BMC and BMD of the lumbar spine, femoral neck, and total body were measured by dual-energy X-ray absorptiometry using a Hologic Discovery device, and bone mineral apparent density (BMAD) of the lumbar spine and the femoral neck were calculated.

Results

We present percentile curves by age derived separately for BMC, BMD, and BMAD of the lumbar spine, left femoral neck, and total body excluding the head for boys and girls. Maximum accretion of BMC and BMD was observed at ages of 11–13 years (girls) and 12–15 years (boys).The prevalence of hypovitaminosis D was high and physical activity was low in our participants. However, in multiple regression analyses, age, BMI, and Tanner stage were the main indicators of BMD and BMAD

Conclusion

These normative data aid in the evaluation of bone density in Iranian children and adolescents. Further research to evaluate the evolution of BMD in Iranian children and adolescents is needed to identify the reasons for significant differences in bone density values between Iranian populations and their Western counterparts.     

Free uroflowmetry versus “Do-It-Yourself” uroflowmetry in the assessment of patients with lower urinary tract symptoms

Introduction

We investigated the possibility that patients could carry out a urine flow assessment at home by themselves, in comfort, without expense and without the use of equipment. We compared this strategy of “Do-It-Yourself” (DIY) uroflowmetry with traditional, hospital uroflowmetry.

Materials and methods

One hundred and twenty patients were enrolled. The patients underwent conventional, free uroflowmetry in hospital. Subsequently, the patients were asked to carry out the following procedure at home: urinate into a graduated container to quantify the total voided volume and determine the flow time by measuring the duration of miction with a stopwatch or simply with the second hand of a clock. This procedure had to be performed three times without preparation.

Results

Hundred patients completed the study. The mean age of the patients analysed was 64.12 years. Their free uroflowmetry values were as follows: the mean voiding time was 44.28 s, the mean voided volume was 290.92 ml, the mean Qmax was 15.17 ml/s, the mean Qmean was 7.87 ml/s, and the mean post-void residual volume was 78.44 ml. The mean Qmean measured by the “DIY-uroflowmetry” was 8.33 ml/s, which was not statistically significantly different (P = 0.12). Assuming that pathological hospital uroflowmetry values are equivalent to a DIY-Qmean ≤10 ml/s and that normal hospital values are equivalent to a DIY-Qmean >10 ml/s, the concordance was 100 %.

Conclusions

Our proposed DIY evaluation of urine flow, together with the International Prostatic Symptom Score (IPSS), provides a good estimate of the results of free uroflowmetry, enabling unnecessary hospital investigations to be avoided.     

Anterior colporrhaphy does not induce bladder outlet obstruction

Introduction and hypothesis

We aimed to evaluate if anterior colporrhaphy causes incomplete voiding due to bladder outlet obstruction.

Methods

Women scheduled for anterior colporrhaphy were asked to undergo multichannel urodynamic investigation before surgery and the first postoperative day. Bladder outlet obstruction was assessed using the Blaivas–Groutz voiding nomogram. Maximum flow rate, detrusor pressure and residual volume were compared between pre- and postoperative measurements and between women with and without an abnormal post-void residual volume (PVR; volume exceeding 150?ml).

Results

Seventeen women participated. One woman who was unobstructed before surgery was obstructed after surgery. Overall, detrusor pressure and maximum flow rate before and after surgery did not differ. After surgery, six women had an abnormal PVR, one was unable to void, four were mildly obstructed and one moderately obstructed.

Conclusion

Urodynamic investigation the first day after anterior colporrhaphy did not show that anterior colporrhaphy induces bladder outlet obstruction. The explanation for postoperative urinary retention can therefore also lie in non-anatomical causes such as postoperative pain and psychological factors.     

Effects of diabetes on female voiding behavior

PURPOSE: We studied voiding behavior in women with type 2 diabetes vs nondiabetic female controls and examined factors associated with voiding dysfunction in patients with diabetes. MATERIALS AND METHODS: After eliminating coexisting medical factors that could affect voiding function we evaluated voiding behaviors in 194 female patients with diabetes treated regularly at a diabetic clinic and 162 control women using a lower urinary tract symptom questionnaire based mainly on the American Urological Association Symptom Index questionnaire and free flow analyses with post-void residual urine estimates. Emptying efficiency was defined as 100% x volume voided/(volume voided + post-void residual urine). RESULTS: Compared with controls patients with diabetes had significantly higher nocturia scores (p = 0.003), weaker urinary streams (p = 0.02), less voided volumes (220 +/- 97 vs 280 +/- 104 ml, p = 0.04) and lower maximal flow rates (19.4 +/- 8.4 vs 25.9 +/- 8.5 ml per second, p <0.001). Remarkable residual urine (100 ml or greater) was detected in 1.8% of controls vs 13.9% of patients. After controlling for age and voided volume diabetes was significantly associated with a decrease in baseline maximum flow of 4.5 ml per second (95% CI 2.9 to 6.2). In patients with diabetes peripheral neuropathy was an independent factor associated with the decrease in emptying efficiency (p = 0.03). CONCLUSIONS: Diabetes significantly altered voiding patterns in a significant proportion of women treated at the diabetic clinic. Peripheral neuropathy is an important factor associated with diabetic voiding dysfunction.     

Urinary citrate excretion in healthy children depends on age and gender

Background

Hypocitraturia is considered a major risk factor for calcium stone formation. However, there is no widely accepted reference database of urinary citrate excretion in children. The aim of our study was to determine the amount of citrate eliminated in the urine over a 24-h period in a pediatric cohort and to determine an optimal unit reflecting excretion.

Methods

The study cohort comprised 2,334 healthy boys and girls aged 2–18 years. The levels of urinary citrate were assessed by an enzymatic method in 24-hour urine and expressed in absolute values, as urinary concentration, citrate/creatinine ratio, per kilogram of body weight, in relation to 1.73 m², and as the calcium/citrate index.

Results

Similar incremental age-related citraturia rates were observed in both male and female subjects until puberty during which time citrate excretion became significantly higher in girls. Urinary citrate adjusted for creatinine and for body weight showed a significantly decreasing trend with increasing age in both sexes. Urinary citrate corrected for body surface was weakly correlated with age. Thus, the assumption of 180 mg/1.73 m²/24 h for males and 250 mg/1.73 m²/24 h for females as lower cut-off values appeared to be reliable from a practical perspective.

Conclusions

We found distinct sex-dependent differences in citraturia at the start of puberty, with significantly higher values of urinary citrate in girls than in boys. Further prospective studies are warranted to elucidate whether this difference represents a differentiated risk of urolithiasis.     

Flow rate nomograms in 7- to 16-year-old healthy children

To construct flow rate nomograms for children, 180 healthy boys and girls aged 7–16 years were examined with a new kind of flowmeter. Each child presented at least two registrations. The flow rate was significantly higher at the second examination and these micturitions were used to construct the nomograms. The relation between flow rate and volume may be described by the function flow = b volume^c, where b and c describe the slope and curvature, respectively. The advantages of using this relation are that non-parametric statistics can be employed, the variation around the median increases with increasing volume, and it is easy to calculate volume corrected flow rates. The exponent 0.5, often used earlier, was found to overestimate flow rates obtained at low volumes. In the constructed nomograms, the exponent varied between 0.29 and 0.42. The volume corrected maximum flow rate was about 2 ml/s higher in girls than in boys. This difference was significant. The difference of about 1.5 ml/s in average flow rate was not significant. The flow rate increased significantly with age. For volume corrected flow rates, there was, however, no significant change with age. Thus, the increase in flow rate with age is secondary to an increase in voided volume. As a result of these analyses, four nomograms were constructed showing the maximum and average flow rates for boys and girls separately. The flow rates of the new nomograms are on a level with or somewhat higher than the flow rates in previously presented nomograms for both children and young adults. © 1994 Wiley-Liss, Inc.     

Measurement of urinary flow rate using ultrasound in young boys and infants

PURPOSE: We present a technique for measuring urinary flow rates with ultrasound in male infants and children. MATERIALS AND METHODS: Urinary flow rate was measured simultaneously by an ultrasound probe placed around the base of the penis and by a funnel with a rotating disk at the bottom in 30 boys with a mean age of 6.7 years (range 4.5 to 10.5), and by ultrasound in 8 infants with a mean age of 10 months (range 1 to 28). Voided volume was measured with a graded cylinder or calculated from the weight change of diapers in infants. Ultrasound and rotating disk maximum flow rates were calculated. The ultrasound signal was calibrated by comparing the collected voided volume to the area under the curve for that void. The volume calculated from the rotating disk flow rate curve was also compared with the collected volume. RESULTS: Both methods yielded similar flow curves. However, ultrasound maximum flow rate significantly exceeded rotating disk maximum flow rate (13 +/- 6 ml. per second, range 5 to 22 versus 10 +/- 4 ml. per second, range 4 to 21, t test p <0.001). The underestimation of the flow rate by the rotating disk method may have been due to adherence of urine to the funnel wall. Rotating disk maximum flow rate was lower and voided volume was underestimated by up to 50% (average 15 +/- 2%) in 21 cases. Ultrasound maximum flow rate averaged 6 +/- 3 ml. per second (range 3 to 11.6 [oldest infant]) in the 8 infants. CONCLUSIONS: Urinary flow rates can be measured accurately using ultrasound in boys who produce small volumes and/or who are not toilet trained and also in infants. In future studies ultrasound will be applied to subsets of male infants with bladder dysfunction.     

What is the relationship between free flow and pressure flow studies in women?

Introduction and hypothesis

The relationship between free flow (FFS) and pressure flow (PFS) voiding studies remains uncertain and the effect of a urethral catheter on flow rates has not been determined. The relationship between residuals obtained at FF and PFS has yet to be established.

Methods

This was a prospective cohort study based on 474 consecutive women undergoing cystometry using different sized urethral catheters at different centres. FFS and PFS data were compared for different conditions and the relationship of residuals analysed for FFS and PFS. The null hypothesis was that urethral catheters do not produce an alteration in maximum flow rates for PFS and FF studies.

Results

Urethral catheterisation results in lower flow rates (p?<?0.01) and this finding is confirmed when flows are corrected for voided volume (p?<?0.01). FFS and PFS maximum flow rates are lower in women with DO than USI (p?<?0.01). A 6-F urethral catheter does not have a significantly greater effect than a 4.5-F urethral catheter. A mathematical model can be applied to transform FFS to PFS flow rates and vice versa. There was no significant difference between the mean residuals of the two groups (FFS vs PFS—two-tailed t?=?0.54, p?=?0.59). Positive residuals in FFS showed a good association with positive residuals in the PFS (r?=?0.53, p?<?0.01)

Conclusions

Urethral catheterisation results in lower maximum flow rates. The relationship can be compared mathematically. The null hypothesis can be rejected.     

Variation in urinary flow according to voiding position in normal males.

Our objective was to study whether the urinary flow rate would vary according to voiding position. Twenty-one normal healthy male volunteers aged 24 to 40 years (mean, 29 years) were studied. The bed used was designed so that a hole could be opened at its center for voiding, and the bed could be bent at two points so that the subject could void in various positions. Urinary flow was measured with a portable uroflowmeter (P-Flow), which permits measuring urinary flow rate. Each subject assumed five voiding positions (standing, sitting, lateral, supine, and prone) in random order. Urinary flow was measured at least twice in each position to record a stable voiding. For voiding in the lateral position, subjects were instructed to void while bending the upper leg to keep an open angle between the legs. All subjects were also instructed to void without increasing abdominal pressure. Maximum flow rate was 20.7 +/- 6.59 mL/sec with voided volume of 262 +/- 77.8 mL in the lateral, 22.1 +/- 7.05 mLl/sec with voided volume of 309 +/- 130 mL in the supine, 25.0 +/- 8.25 mL/sec with voided volume of 287 +/- 122 mL in sitting, 27.1 +/- 8.89 mL/sec with voided volume of 263 +/- 102 mL in the standing, and 28.7 +/- 10.6 mL/sec with voided volume of 303 +/- 98 mL (mean +/- SD) in the prone positions. The maximum and mean urinary flow rates were greatest in the prone position. With regard to these parameters, significant differences were noted between the prone and lateral positions and between the prone and supine positions. In conclusions, the maximum urinary flow rate was highest in the prone position, followed by the standing, sitting, supine, and finally the lateral positions in normal males. Neurourol. Urodynam. 18:553-557, 1999.     

Analysis of female voiding dysfunction: a prospective, multi-center study

Purpose

Female voiding dysfunction lacks clear definitions or objective data even to this day due to the relatively low prevalence and complex etiologies of voiding dysfunction in women compared to men. The prevalence varies widely from 2.7 to 23 % (Nitti et al. in J Urol 161(5):1535–1540, 1999; Rees et al. in Br J Urol 47(7):853–860, 1975; Groutz et al. in Neurourol Urodyn 19(3):213–220, 2000; Farrar et al. in Br J Urol 47(7):815–822, 1975; Massey and Abrams in Br J Urol 61(1):36–39, 1988; Chassagne et al. in Urology 51(3):408–411, 1998). Diagnostic criteria and management of female voiding dysfunction have not yet been established. We performed a prospective, multi-center study at nine hospitals to investigate the characteristics and prevalence of female voiding dysfunction.

Materials and methods

A total of 1,415 women visited urology clinics in nine hospitals from September to December 2005. Among them, 792 patients presented with lower urinary tract symptoms (LUTS). We analyzed their urinary symptoms with an International Prostate Symptom Score (IPSS) and obtained objective data using uroflowmetry, residual urine volume, and urinalysis. The authors hereby define female voiding dysfunction as maximum flow rate (Q _max) of 15 ml/s or less, which may be due to either bladder outlet obstruction (BOO) or bladder dysfunction caused by detrusor underactivity. BOO was defined as Q _max <15 ml/s with detrusor pressure >20 cmH₂O at Q _max, and detrusor underactivity was defined as Q _max <15 ml/s with detrusor pressure <20 cmH₂O at Q _max on pressure flow studies.

Results

Hundred and two patients (12.8 %) from a total of 792 LUTS patients complained of voiding difficulty. Mean total IPSS score, mean IPSS subscores for voiding and storage symptom was 19.5 ± 7.9, 12.0 ± 5.0, and 8.4 ± 3.4, respectively. Among the seven categories of IPSS, incomplete emptying was the most common symptom followed by weak stream. Eighty-nine patients (87.2 %) from a total of 102 voiding dysfunction patients showed BOO, while 13 patients (12.8 %) showed detrusor underactivity. Concomitant diseases observed with voiding dysfunctions were overactive bladder (32 patients), stress urinary incontinence (25), detrusor underactivity (13), previous stress urinary incontinence surgery (12), pelvic organ prolapse (4), and anatomical obstruction (3 patients).

Conclusion

The prevalence of voiding difficulty in female urology patients who visit urologic office clinic was 7.2 and 12.8 % in female LUTS patients. Voiding symptoms were more common than storage symptoms, while functional BOO was more prevalent than detrusor underactivity in female voiding difficulty patients. We may expect alpha blockers to be an effective treatment option in female voiding difficulty due to functional BOO.