Your doctor may recommend this test if there's concern about your ability to empty your bladder completely, particularly if you are older, have had prior bladder surgery or have diabetes. This test can tell how well your bladder is functioning. A specialist uses an ultrasound scan, which translates sound waves into an image, to view how much urine is left in your bladder after you urinate (PVR). In some cases, a thin tube (catheter) is passed through the urethra and into your bladder. The catheter drains the remaining urine, which can then be measured.
How to prepare
For any appointment with a urologist, it is a good idea to come to the clinic with a full bladder and assume you will need to give a urine sample. Ask the check in desk if a urine test is required as you register, especially if you have to go urgently.