Patient Information

Flow and Residual Volumes Scan


What is this procedure?

This is a basic non-invasive bladder function test.

What must I do before the procedure?

This procedure requires a full bladder. Please drink 2 pints of water (or non-alcoholic liquids) an hour prior to your appointment. If you are unable to travel with a full bladder or have a heart condition and you have been told not to drink a lot of water, please attend the department an hour early and use the drinking facilities here top try and keep your bladder as full as possible. Once you have a full bladder the test only takes a few moments to do.

What are the intended benefits of this procedure?

To enable the nurse specialist to assess your normal urine flow and the amount of urine left in your bladder after urinating, if any.

This test provides the consultant with information to help them diagnose any urinary problems.

What are the alternatives to this procedure?

There are no alternative tests or procedures. We would need to rely on observing your symptoms.

What are the risks?

There are no risks.

What sort of anaesthetic is used?

 No anaesthetic is required for this procedure.

What does the procedure involve?

Once your bladder is comfortably full, a nurse specialist will ask you to urine into a flowmeter, a special toilet that measures the flow of your urine.

We will then ask you to lie on a couch so that the nurse can scan your bladder area to check for any remaining urine in the bladder. To do this, the nurse will put a small amount of scanning gel on your pubic line and pass the scanner gently over this area.

What happens after the procedure?

If your consultant has requested this test, you will normally have an appointment to discuss the results with them on the same day.

If your GP (family doctor) requested this test, we will give you a copy of the result to take back for them to review.

Who should I contact for more information?

  • Specialist Urology nurses
  • Urodynamics Team
  • Specialist Urology Oncology Nurses if you have a cancer condition and would like further information regarding this
  • Your Urology Consultant via their secretaries


Specialist Urology nurses 0208 934 3547
Urodynamics Team 0208 934 3038
Urology Consultants' Secretaries 0208 934 6041
Specialist Urology Oncology Nurses 0208 934 2729

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