a ) Urodynamics testing is often used to try and find out what is causing bladder problems. Here we give you the "low down" on what this test involves, and how you can prepare yourself.

Urodynamics is the study of the pressure of urine in the bladder, and the flow of urine leaving the bladder. Urodynamics testing can give useful information and may help work out the cause of bladder problems. This may help to choose an effective treatment too.

• Why might the test be used?
  You may have a bladder problem which is still something of a mystery to the doctors. Or you may already have a diagnosis, but the doctor needs more information on the extent of your condition. It could also be that your doctor is thinking about surgery, and the test can make sure the operation will help.
  
  What does urodynamics tell you?
  The test measures how long it takes to empty your bladder, and whether the flow of urine is even, or if it stops and starts. It measures the way the bladder contracts to start the flow of urine, and how much pressure there is in the bladder and urethra (the tube that carries urine out of the bladder).
  
  Where is the test normally done?
  You will be asked to go to a special hospital clinic for the test. It usually takes about an hour and a half to complete.
  
  What happens?
  No one can pretend that urodynamics is a pleasant procedure. But in good clinics, staff will do their best to put you at ease and make sure you are treated sensitively. One continence nurse specialist told us she tries to be aware of how her patients are feeling. "I make sure that there is privacy and that the person feels secure. I explain everything that I do and let them know that they can stop me at any time", she said.
  
  The first thing you will be asked to do is to lie down on a couch. A fine tube, called a catheter, is inserted into your bladder - through the opening in the tip of the penis in men, and in the small opening above the vagina in women. A second very fine catheter is inserted at the same time. This is not painful, though it may be a bit uncomfortable. You will also have a third catheter inserted into your rectum (back passage).
  
  The first catheter is used to fill your bladder with fluid. The second catheter is attached to a sensor which records the pressure inside your bladder. The third is also attached to a sensor, and it records the pressure in your abdomen. These sensors record the pressure in the bladder - and the changes in pressure as it fills up with fluid. They also record what happens when you cough or move around. All these catheters are linked to a computer which prints out a graph of all the changes.
  
  Once your bladder is full you will be asked to stand and cough, and then to pass urine into a commode. The commode has a flow-meter inside it, again linked up with a machine which prints out the result. You should be able to do all this in private. The catheters are taken out as soon as the test is over.
  In some clinics you may be given an X-ray which records what is happening on film. You lie down, and the X-ray machine is positioned above your bladder.
  The report of these tests is then sent to the doctor investigating your bladder condition, or to your family doctor.
  
  b) Urodynamics is the study of how the body stores and releases urine. Urodynamic tests help your doctor or nurse see how well your bladder and sphincter muscles work and can help explain symptoms such as
  

• incontinence
• frequent urination
• sudden, strong urges to urinate
• problems starting a urine stream
• painful urination
• problems emptying your bladder completely
• recurrent urinary tract infections
  
  Urodynamics Testing
  

An urodynamic test is a procedures designed to provide information about a bladder problem. The type of test you take depends on your problem.

Uroflowmetry – This test measures the amount of urine and the flow rate (how fast the urine comes out). You may be asked to urinate privately into a toilet that contains a collection device and scale.

Cystometry – This test measures how much your bladder can hold, how much pressure builds up inside your bladder as it stores urine, and how full it is when you feel the urge to urinate. The doctor or nurse will use a catheter to empty your bladder completely. Then a special, smaller catheter with a pressure-measuring tube called a cystometer will be used to fill your bladder slowly with warm water. Another catheter may be placed in the rectum to record pressure there as well. You will be asked how your bladder feels and when you feel the need to urinate. The volume of water and the bladder pressure will be recorded. You may be asked to cough or strain during this procedure. Involuntary bladder contractions can be identified.

Urethral Pressure Profile – This procedure measures the different pressures in your urethra as a catheter is slowly removed from the bladder.

Pressure Flow Study – For this test, you will be asked to empty your bladder so that a catheter can measure the pressures required to urinate. The pressure flow study helps to identify bladder outlet obstruction.