A urodynamic test is regarded as “the gold standard” in assessing urinary symptoms. It is, however, important to realise that most people with urinary incontinence or bothersome urinary symptoms do not need to have a urodynamic study.
In the majority of people, the history, physical examination and basic investigations are enough to make the diagnosis of the type of incontinence and start treatment.
What is a Urodynamic Study?
A urodynamic study is a test of bladder and urethral sphincter (urinary control valve) function using computerised equipment.
The test involves measuring pressures within the urinary tract through the use of specialised electronic equipment, computer analysis and is performed using a very fine catheter (tube) inserted into the bladder via the urethra (urine pipe which drains urine from the bladder).
The aim of the urodynamic study is to reproduce the troublesome urinary symptoms to give a more precise diagnosis of the bladder problem so that further treatment can be accurately planned.
Who needs a Urodynamic Study?
Some of the reasons people need a urodynamic study include:
- To define the type of incontinence, particularly when the history is unclear e.g. in cases of very severe incontinence with continuous leakage
- When invasive or surgical treatments for incontinence are being considered
- When the conservative and initial measures in treating urinary incontinence have not been successful
- In people who have a complex history or medical problems such as:
- A history of previous Urological surgery or Gynaecological surgery including surgery for incontinence or prolapse
- Unsuccessful previous surgery
- An unclear diagnosis
- Mixed stress and urge incontinence symptoms – to help determine the different treatment options
- Neurological disorders e.g. spinal cord injuries, strokes, head injuries, multiple sclerosis, Parkinson’s disease
What happens during the Test?
- The test is performed without any need for anaesthetic, sedation or fasting.
- Initially patients pass urine into a special toilet to measure urine flow (also known as uroflowometry).
- Very slim catheters (tubes) are then inserted into the bladder and back passage (rectum) to provide pressure readings in the bladder and abdomen. Local anaesthetic gel is used during the study to help make insertion of urodynamic catheters more comfortable.
- The bladder is filled using the catheter and pressure measurements are continuously recorded as well as patient feedback regarding bladder sensation and urgency.
- Testing for stress incontinence is performed with coughing and straining. Leakage episodes are recorded and analysed to provide information regarding the type and severity of incontinence.
- At the end of the test, urine is passed to further assess bladder function and look for blockage of urinary flow.
- The urodynamic test can be combined with a form of X ray to provide extra information regarding the structure and anatomy of the urinary tract.
- The urodynamic study can also be combined with another test such as flexible cystoscopy to provide information regarding the structure of the urethra, bladder and in men the prostate.
- Results of the urodynamic study are discussed on the spot and further treatments (e.g. with medication) can be started immediately after the test.
Will it be uncomfortable?
Local anaesthetic gel is used to help numb the area before inserting the tubes but there may be some mild discomfort.
Most people find that the test is not as unpleasant as the chronic bladder problems with which they have been living.
What information is gained from a Urodynamic Study?
The aim of the urodynamic study is to reproduce the bothersome urinary symptoms so that the underlying problem with the urinary tract is shown.
The urodynamic study provides information about:
- Bladder overactivity – showing evidence of “detrusor overactivity” or unstable bladder contractions
- Bladder compliance – the elasticity of the bladder wall which may be impaired in neurological conditions or with previous pelvic radiation
- Stress urinary incontinence – showing the type and severity of stress incontinence which helps guide the choice of surgical treatment
- Obstruction- showing the site and severity of blockage in the urinary tract e.g. due to enlargement of the prostate in men, due to prolapse in women, due to neurological disorders
- Quality of the bladder muscle contraction – which can decline with ageing, medical problems such as diabetes and neurological problems