Recent advances in urodynamics in women.

Urodynamics is the study of the storage and evacuation of urine from the urinary tract. The aim is to reproduce the patient's symptoms and provide a pathophysiological explanation for them by identifying all factors that contribute to the lower urinary tract dysfunction, including those that are asymptomatic. Urodynamics consists of various tests, each of which is designed to assess a different aspect of lower urinary tract function. There is a lack of evidence regarding when urodynamics should be used in the non-neurogenic bladder. Some small randomised controlled trials suggest that urodynamics does not alter the outcome of surgery for stress urinary incontinence when compared with office evaluation alone. However, this is widely felt to be inaccurate and many health-care professionals still advocate the use of urodynamics prior to any invasive treatment, especially surgery on the lower urinary tract. There have been few technological advances in urodynamics in recent years. Air-charged rather than fluid-filled catheters were thought to help reduce artefact, but the evidence is unclear, and there is doubt over their accuracy. Ambulatory urodynamics is carried out over a longer period of time, enabling physiological bladder filling, but it remains invasive and artificial. To attempt to replicate symptoms more accurately, there have been efforts to develop wireless devices to measure detrusor pressure directly. These may be promising but are far from suitable in humans at present. Urodynamics continues to provide useful information for assessing lower urinary tract function, but further large studies are required to assess its value and develop innovations to improve the accuracy of the tests and acceptability to patients.