Urodynamics

A Detailed Look

A urodynamic study is a series of tests that gives your doctor a detailed look at the function of your bladder and urethra. These tests can help your doctor evaluate any problems you may be having with storing urine or voiding (eliminating) urine from your body.

Why You Need a Urodynamic Study

A urodynamic study may be recommended if you have problems with storing or voiding urine, and your doctor needs to evaluate these problems further. Possible problems that you may have include the following:

  • You may be incontinent (leak urine).
  • Your bladder may not empty completely.
  • You may have symptoms, such as the frequent need to urinate or a constant, urgent need to urinate.
  • Your urine stream may be intermittent or weak.
  • You may have persistent urinary tract infections.

Preparing for the Study

You will be told how to prepare for the urodynamic study. Tell your doctor which medications you are taking, and ask whether you should stop them before the study. You may be asked to keep a diary of your urination habits for a few days before the study. This diary can be a helpful part of your evaluation. You need to arrive for the study with a full bladder.

Tests That May Be Done

At certain points during the study you’ll probably be asked to urinate. Try to relax to help make the study results as realistic and reliable as possible. A catheter (soft, hollow tube) or special sensor may be placed in your urethra and your rectum to help with the study. Tests that may be done during the study include:

  • Uroflowmetry: This test measures the amount and speed of urine you void from your bladder. You urinate into a funnel attached to a computer that records your urine flow over time. The amount of urine left in your bladder after you void may also be measured immediately after this test.
  • Cystometry: This test evaluates how much the bladder can hold, how strong the bladder muscle is, and how well the signals work that tell you when your bladder is full. Through a catheter, your bladder is filled with sterile water or saline solution. You’re asked to report any sensations you feel and whether they’re similar to symptoms you’ve felt at home. You may be asked to cough, stand and walk, or bear down during this test.
  • Electromyogram: This test helps evaluate the muscle contractions that control urination. Electrode patches or wires may be placed near the rectum and urethra to make the recording. You may be asked to try to tighten or relax your sphincter muscles during this test.
  • Pressure Flow Study: This test measures the pressure and flow of urine out of your bladder. It is often performed after cystometry. You’re asked to urinate while a catheter in the urethra measures pressures.

Getting Your Results:

When the study is finished, you’ll get dressed and return to the consultation room. Test results may be available soon after the study is finished, or you may return to your doctor’s office in a few days for your results.