The types of urodynamic testing available to study the function of the bladder and urethra range from leak point pressure tests to imaging studies of urinary tract. The goal of all urodynamic tests is to assess the health of the urinary tract to learn more about why a patient is experiencing problems like incontinence or difficulty urinating. Usually, a full urinalysis is performed first to look for signs of infection or inflammation and if these results are negative, urodynamic testing will be recommended as the next step in diagnosis.
Urodynamic testing usually includes several tests performed together and can take about an hour. It may be done in a hospital or clinic and patients are typically instructed to have several glasses of water before the test so that they start with a full bladder.
In the most simple testing, patients are asked to urinate into a container that will measure the amount of urine produced, as well as the flow rate. This information can be charted and the care provider may also listen while the patient urinates for any signs of abnormalities. Once the bladder has been emptied, another type of urodynamic testing can be conducted when the care provider measures the post-void residual, looking at how much urine is left.
Cystometry is another type of testing available. In this test, catheters are inserted into the bladder and it is filled with warm water. The patient is asked to report on when the need to urinate becomes urgent and sensors in the bladder are used to measure bladder pressure during the test. A leak point pressure point can be determined during this test by seeing how full the bladder becomes before the patient starts to release fluid automatically.
A pressure flow study can be used to determine how much pressure the patient needs to exert to void the bladder. Imaging studies performed by using contrast agents, and equipment such as computed tomography (CT) scanners are another option for urodynamic testing. Doctors can also use video studies to map out the function of the urinary tract as the bladder fills and empties. If a doctor suspects that a neurological problem or damage to the muscles in the area might be involved, an electromyograph test that measures electrical impulses in the muscles can be conducted.
The urodynamic testing options available will be discussed with a patient before he goes in for testing. The doctor can provide a list of recommended tests and provide patients with information about what to expect.