What are Urodynamics?

Urodynamics are tests that assess how well your lower urinary tract is functioning. Specifically, they evaluate its ability to hold and release urine, as well as show if any blockages or leaks are present. The lower urinary tract is made up of the following:

  • The bladder, which stores urine.
  • The urinary sphincters, which are muscles around the opening of the bladder that hold urine in.
  • The urethra, which is the tube where urine flows out of the body.
Urodynamics tests are normally performed together as one series, but depending on your symptoms, only one or some of them may be necessary. The most common tests are:
  • Cystometrogram, which measures the amount of urine the bladder can store and how full it is before you have the urge to urinate. Your doctor may order this test if she suspects you have a weak bladder.
  • Pressure flow study, which measures the pressure in the bladder while urinating. This test helps locate a blockage in the bladder.
  • Uroflowmetry, which measures how much and how fast urine flows out of the body. This test is usually recommended when you have difficulty urinating or you have a slow stream.
  • Urethral sphincter electromyography, which measures how strong the muscles and nerves in the bladder and sphincters are. Your doctor may request this test if the problem you are experiencing is linked to muscle or nerve damage in the lower urinary tract.
  • Urethral pressure profile, which measures the pressure along the urethra while the bladder is gradually filled with fluid. Low pressure could mean you have a weak urethra, a contributing factor to urinary incontinence (loss of bladder control).
For a few hours following a urodynamics study, you will likely feel some soreness or discomfort. You should drink at least one glass of water every half hour for two hours to relieve these symptoms. Holding a warm, moistened washcloth over the area where you feel discomfort or taking a warm bath may also help. Results for cystrometrograms and uroflowmetry are typically available immediately after the test, but results for the other tests may take a few days. When your doctor has reviewed your test results, she will discuss them with you, along with any treatments you may need.