Cystometry is a test that measures the pressure inside of the
bladder to see how well the bladder is working.
Cystometry is done when a muscle or nerve problem may be causing problems with
how well the bladder holds or releases urine.
Urination is a
complex process. As the bladder fills, nerves in the bladder wall send a
message to the
spinal cord and brain that you need to urinate. In response, your spinal cord
sends a signal for the bladder to contract (voiding reflex). When you hold in
your urine, your brain is overriding this reflex. When you allow the reflex to
occur, urination occurs. A problem affecting this nerve pathway or the muscles
of the bladder wall can cause bladder dysfunction.
cystometry, your bladder is filled with water or gas to measure its ability to
hold in and push out the water or gas. Medicine may also be given to see
whether your bladder contracts or relaxes normally in response to the medicine.
A small tube (catheter) can be placed in your
rectum to measure pressure as the bladder fills. A
small pad or needle may be placed near your
anus to measure muscle function in this area.
Why It Is Done
Cystometry is done to:
- Find the cause of problems with the
bladder or the muscle that holds urine in the bladder
(bladder sphincter). Problems in one or both of these areas may cause
uncontrolled urine leakage, an urgent feeling that you have to urinate, or a
weak urine stream.
- Measure how much urine your bladder can store and how much urine
remains in your bladder after you feel you have completely emptied it (residual
- Help you and your doctor make decisions about how to treat your
- See how well the bladder works in people with
progressive neurological diseases, such as
How To Prepare
Tell your doctor if you:
- Are taking any medicines. Some medicines and herbal supplements
can affect bladder function.
- Are or might be pregnant.
- Have symptoms of a
urinary tract infection, such as pain or burning with
urination, foul-smelling or cloudy urine, or an urge to urinate more often than
Talk to your doctor about any concerns you have regarding
the need for the test, its risks, how it will be done, or what the results will
mean. To help you understand the importance of this test, fill out the
medical test information form(What is a PDF document?).