This is the ¢rst report of the International Continence Society (ICS) on the development of comprehensive guidelines for Good Urodynamic Practice for the measurement, quality control, and documentation of urodynamic investigations in both clinical and research environments. This report focuses on the most common urodynamics examinations; uro£owmetry, pressure recording during ¢lling cystometry, and combined pressure^£ow studies. The basic aspects of good urodynamic practice are discussed and a strategy for urodynamic measurement, equipment set-up and con¢guration, signal testing, plausibility controls, pattern recognition, and artifact correction are proposed. The problems of data analysis are mentioned only when they are relevant in the judgment of data quality. In general, recommendations are made for one speci¢c technique. This does not imply that this technique is the only one possible. Rather, it means that this technique is well-established, and gives good results when used with the suggested standards of good urodynamic practice. Neurourol. Urodynam.21: 261^274,2002. ß 2002 Wiley-Liss, Inc.Key words: urodynamics; standardisation; uro£owmetry; cystometry; pressure-£ow studies INTRODUCTIONA Good Urodynamic Practice comprises three main elements:A clear indication for and appropriate selection of, relevant test measurements and procedureŝ Precise measurement with data quality control and complete documentation Accurate analysis and critical reporting of resultsThe aim of clinical urodynamics is to reproduce symptoms whilst making precise measurements in order to identify the underlying causes for the symptoms, and to quantify the related pathophysiological processes. By doing so, it should be possible to establish objectively the presence of a dysfunction and understand its clinical implications. Thus, we may either con¢rm a diagnosis or give a new, speci¢cally urodynamic, diagnosis. The quantitative measurement may be supplemented by imaging (videourodynamics).Urodynamic measurements cannot yet be completely automated, except for the most simple urodynamic procedure, uro£owmetry. This is not an inherent problem of the measurement itself, but is due to the current limitations of urodynamic equipment and the lack of a consensus on the precise method of measurement, signal processing, quanti¢cation, documentation, and interpretation. With the publication of this ICS Standardisation document on good urodynamic practice, it is expected that the necessary technological developments in automation will follow.Urodynamics allows direct assessment of lower urinary tract (LUT) function by the measurement of relevant physiological parameters. The ¢rst step is to formulate the 'urodynamic question or questions' from a careful history, physical examination, and standard urological investigations. The patient's recordings of micturitions and symptoms on a frequency volume chart, and repeated free uro£owmetry with determination of post-void residual volume provide important noninvasive, objective information that helps to ...

The concept of the passive urethral resistance relation (PURR) to quantify bladder outflow conditions in few parameters from the complex pressure/flow relation is generally accepted. The most simple, yet realistic, linearized format is the linear PURR (linPURR). This two-dimensional format allows clear identification of individual outflow conditions with distinction of different obstruction types. Unequivocal grading of obstruction, however, requires a one-dimensional format. Theoretical considerations show that voiding function can be completely defined by a single parameter only when detrusor strength and obstruction type are uniform. This can be achieved with a disease-specific approach such as our pressure/flow diagram, which is specific for prostatic obstruction. It allows grading of obstruction stepwise for clinical decisions making or on a continuous scale for statistical applications using the maximal flow rate with related detrusor pressure as a single data point alone. Adding the actual linPURR to the diagram offers the unique feature of inherent conceptual quality control, relevant for individual assessment. The detrusor-adjusted mean PURR factor (DAMPF) is an alternative format of reducing the PURR to a single number, excluding at least the impact of variable detrusor strength, a conceptual advantage when the obstruction type is less uniform. The voiding pressure at maximal flow is a suitable parameter for most simple obstruction grading. Its validity can be significantly enhanced only when it is used in a disease-specific format, such as our pressure/flow diagram in combination with linPURR and DAMPF. Computerization does not improve the results of manual graphical analysis. Much more important is the clear conceptual definition and transparent application. More sophisticated computer-dependent methods such the original PURR/DURR and the three-parameter model can abstract more detailed information about outflow conditions, which requires expertise in their application and perfect data quality, but this does not result in better obstruction grading.

These guidelines provide benchmarks for the performance of urodynamic equipment, and have been developed by the International Continence Society to assist purchasing decisions, design requirements, and performance checks. The guidelines suggest ranges of specification for uroflowmetry, volume, pressure, and EMG measurement, along with recommendations for user interfaces and performance tests. Factors affecting measurement relating to the different technologies used are also described. Summary tables of essential and desirable features are included for ease of reference. It is emphasized that these guidelines can only contribute to good urodynamics if equipment is used properly, in accordance with good practice.

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Objective  To explore the relationship between uroflow variables and lower urinary tract symptoms (LUTS); to define performance statistics (sensitivity, specificity, positive and negative predictive values) for maximum urinary flow rate (Qmax ) with respect to bladder outlet obstruction (BOO) at various threshold values; and to investigate the diagnostic value of low‐volume voids. Patients and methods  The study comprised 1271 men aged between 45 and 88 years recruited from 12 centres in Europe, Australia, Canada, Taiwan and Japan over a 2‐year period. Symptom questionnaires, voiding diaries, uroflowmetry and pressure‐flow data were recorded. The relationship between uroflow variables and symptoms, Qmax and BOO, and the diagnostic performance of low volume voids were analysed. Results  The relationship between symptoms and uroflow variables was poor. The mean difference between home‐recorded and clinic‐recorded voided volumes was −48 mL. Qmax was significantly lower in those with BOO (9.7 mL/s for void 1) than in those with no obstruction (12.6 mL/s; P<0.001) and Qmax was negatively correlated with obstruction grade (Spearman’s correlation coefficient −0.3, P<0.001), even when controlling for the negative correlation between age and Qmax (Spearman’s partial correlation coefficient −0.29, P<0.001). A threshold value of Qmax of 10 mL/s had a specificity of 70%, a positive predictive value (PPV) of 70% and a sensitivity of 47% for BOO. The specificity using a threshold Qmax of 15 mL/s was 38%, the PPV 67% and the sensitivity 82%. Those voiding <150 mL (n=225) had a 72% chance of BOO (overall prevalence of BOO 60%). In those voiding >150 mL the likelihood of BOO was 56%. The addition of a specific threshold of 10 mL/s to these higher volume voiders improved the PPV for BOO to 69%. Conclusion  While uroflowmetry cannot replace pressure‐flow studies in the diagnosis of BOO, it can provide a valuable improvement over symptoms alone in the diagnosis of the cause of lower urinary tract dysfunction in men presenting with LUTS. This study provides performance statistics for Qmax with respect to BOO; such statistics may be used to define more accurately the presence or absence of BOO in men presenting with LUTS, so avoiding the need for formal pressure‐flow studies in everyday clinical practice, while improving the likelihood of a successful outcome from prostatectomy. This study also shows that low‐volume uroflowmetry can provide useful diagnostic information and that, as such, the data from such voids should not be discarded.

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Clinical efficacy and adverse effects of oxybutynin and propantheline in the treatment of symptoms related to detrusor hyperactivity were studied in a randomized, controlled, double-blind multicenter trial. Of 169 patients entered into the study 154 were evaluable for statistical analysis. Mean grade of improvement (visual analogue scale) was significantly higher with oxybutynin (58.2%) versus propantheline (44.7%) and placebo (43.4%). Mean bladder volume at first involuntary cystometric contraction was significantly increased with oxybutynin (+57.0 ml.) versus placebo (-9.7 ml.). Mean maximum cystometric bladder capacity was also significantly increased with oxybutynin (+80.1 ml.) versus placebo (+22.5 ml.). Rate of inquired possible adverse effects was significantly higher for oxybutynin (63%) versus propantheline (44%) and placebo (33%). However, only 5 patients dropped out of the study because of adverse effects (oxybutynin 2 and propantheline 3). No serious or lasting adverse effects were encountered with dryness of the mouth being the major complaint. Oxybutynin has statistically significant effects on subjective symptoms and objective urodynamic parameters in patients with detrusor hyperactivity compared to propantheline.