Cystometry is done in a doctor's office or hospital urology department by a urologist, gynecologist, or other trained health professional.
You will need to take off most of your clothes below the waist. You will be given a cloth or paper covering to use during the test.
At the beginning of the test, you will be asked to urinate into a toilet that is connected to a machine called a uroflowmeter. This machine measures how much urine passes and how long it takes. The time and effort needed to start the flow of urine, the number of times you start and stop the flow of urine, and the presence of dribbling near the end of urinating are also recorded.
Next, you will be asked to lie on your back on an examining table. After the urethra is thoroughly cleaned, a well-lubricated thin, flexible tube (catheter) is gently inserted and slowly moved into your bladder. Any urine remaining in your bladder (residual volume) will be drained and measured.
Next, a catheter is used to fill your bladder with sterile, room-temperature water. The catheter is also attached to a device called a cystometer, which measures how much your bladder can hold and the pressure in your bladder. You will be asked to report any feelings such as warmth, bladder fullness, or an urge to urinate. The process may be repeated.
Another catheter may be placed in your rectum to measure the pressure in your abdomen as your bladder fills. A small pad or needle may be placed near your anus to measure muscle function in this area.
Each time your bladder is filled, you will be asked to report when you first feel the urge to urinate. Your bladder will then continue to be filled until you report that you feel you must urinate. Then the catheter will be used to drain the bladder, or you will be asked to urinate.
After all the liquid is drained out of your bladder, and if no additional tests are required, the catheter is removed.