DEAR DOCTOR K: I’m a 65-year-old woman with urinary incontinence. My doctor isn’t sure what’s causing it, so I need to have urodynamic testing. What information will this test give my doctor?
DEAR READER: Urodynamic testing is a series of tests that evaluate your urinary system in action. A doctor may want to do these tests if the cause of your incontinence isn’t clear. Testing is also recommended if standard treatments haven’t helped.
The urodynamic test is likely to include one or more of the following procedures:
• Uroflowmetry measures the amount of urine you produce and the rate of the flow. A slow flow might indicate an obstruction in the urethra or a weak bladder muscle.
• Post-void residual volume measures the amount of urine left in your bladder after you urinate. This is particularly valuable if you’ve had repeated urinary tract infections, if you have a neurological disorder, or if your doctor suspects a blockage is preventing your bladder from emptying properly.
• Cystometry monitors how pressure builds up in your bladder as it fills with urine, how much urine your bladder can hold and at what point you feel the urge to urinate.
This test can reveal abnormal contractions or spasms of your bladder muscle; signs of stress incontinence; and evidence that your urethra is unable to close completely. If you have low urine flow, this test can show whether this is due to weak bladder contractions or a blockage.
• Electromyography (EMG) uses small electrode patches to help determine whether your nerves and muscles are working together to properly coordinate the activities of your bladder and urethra.
• Cystography is an X-ray test performed during cystometry or uroflowmetry. It can pinpoint the location of a blockage or reveal a urethra that doesn’t close tightly enough.
• Video-urodynamic study is a computerized test measuring urine flow and pressure in the bladder and rectum. It may provide useful information about your bladder and urethral function, especially if you have problems urinating.