ABSTRACT
I. INTRODUCTION The primary aim of clinical urodynamics is to provide an objective explanation of symptoms with a view to guiding treatment. To this end, tests must be reproducible, reliable, and specific to the condition under investigation. It is over a century since Dubois (1) and Mosso and Pellacani (2) described the measurement of intravesical pressure during filling and voiding, respectively. In the 1950s and 1960s “hydrodynamics” or “urodynamics” gained recognition in clinical practice (3,4). During the 1970s, understanding of outflow obstruction improved with Griffiths’ work defining the relation between pressure and flow through distensible tubes (5). Cystometric findings were shown by several workers to be predictive of outcome following outflow surgery in men and continence surgery in women. The techniques and terminology used, in what have now come to be referred to as “conventional” or “static” urodynamic investigation, were standardized by the International Continence Society during the 1980s (6). Ambulatory urodynamic monitoring may broadly be defined as any cystometric investigation performed outside the laboratory utilizing “natural” bladder filling. The principal aim of ambulatory urodynamics is to reproduce a patient’s symptoms and measure associated detrusor and sphincter function during natural filling in a normal environment. In the adult human, the detrusor is unique as the only involuntary muscle under direct cortical control. Therefore, in addition to the effects of nonphysiological filling, detrusor function may be further influenced by environmental conditions prevalent during conventional testing. Whereas static urodynamic investigation was introduced largely unchallenged as a peerless investigation of lower urinary tract function, ambulatory monitoring must be shown to have clear evidence of clinical benefit before its introduction into mainstream practice. This process has been hindered by a lack of validated protocols for its
conduct and interpretation and by concerns over data quality and reliability. The following chapter highlights the advantages and drawbacks of ambulatory monitoring in a range of clinical and research settings, with particular reference to our extensive experience of this modality in our unit.
