Uroflometry is a test to measure the volume of urine voided (excreted), the velocity or speed it was excreted, and how long the excretion took.
How the test is performed
You will urinate in a special urinal or toilet equipped with a machine with a measuring device.
You are asked to press a button shortly before you try to begin urination, and you may be required to press the button again when urination is complete. This machine will create a report for your health care provider to evaluate.
How to prepare for the test
Your provider may ask you to temporarily discontinue medications that can alter test results.
Uroflometry is best preformed with a full bladder. Do not urinate for 2 hours prior to the test. Increase the volume of fluids you drink so you will have plenty of urine for the test.
Do not place any toilet tissue in the urine receptacle.
Infants and children:
The preparation you can provide for this test depends on your child’s age, previous experiences, and level of trust. For general information regarding how you can prepare your child, see the following topics:
- Preschooler test or procedure preparation (3 to 6 years)
- Schoolage test or procedure preparation (6 to 12 years)
- Adolescent test or procedure preparation (12 to 18 years)
How the test will feel
The test involves normal urination, so you should not experience any discomfort.
Why the test is performed
This test is useful in evaluating the function of the urinary tract.
Normal values vary depending on age and sex:
- Age: 4 to 7 o The average flow rate for both males and females is 10 mL/sec.
- Age: 8 to 13 o The average flow rate for males is 12 mL/sec. o The average flow rate for females is 15 mL/sec.
- Age: 14 to 45 o The average flow rate for males is 21 mL/sec. o The average flow rate for females is 18 mL/sec.
- Age: 46 to 65 o The average flow rate for males is 12 mL/sec. o The average flow rate for females is 15 mL/sec.
- Age: 66 to 80 o The average flow rate for males is 9 mL/sec. o The average flow rate for females is 10 mL/sec.
What abnormal results mean
Several circular muscles normally regulate urine flow, and if any of these muscles becomes weak or dysfunctional, an increase in urine flow or urinary incontinence may result.
If there is a bladder outlet obstruction or if the bladder muscle is weak, a decrease in urine flow may result.
Any abnormal results should be discussed with you and explained by your health care provider.
What the risks are
There are no risks associated with this test.
by Janet G. Derge, M.D.