Urodynamics is the investigation of the function of the lower urinary tract to diagnose the reason for urinary incontinence or voiding dysfunction.
The lower urinary tract includes:
- Bladder: A muscular balloon-like organ in the pelvic region that stores the urine
- Urethra: The tube connected to the bladder through which the urine flows out of the body
- Sphincters: Muscles in the urinary bladder that help in holding the urine in the bladder. They tighten and relax in coordination with the bladder muscle on signals from the brain and leads to urine storage or release of the urine through the urethra out of the body, upon command.
Lack of coordinated function in any of the above parts of the urinary tract can lead to lack of bladder control including leakage (incontinence) or inability to void properly (voiding dysfunction).
Indications for Urodynamics
The urodynamics test is advised in patients with symptoms of urine leakage, frequent urination, recurrent urinary infections, pain during urination, sudden urge to urinate and problem in starting urination or completely emptying the bladder. This test is usually performed before any reconstructive surgery to obtain a better understanding of bladder function and how the bladder should function after surgery.
Urodynamic testing looks at how the coordinated functioning of the bladder, sphincters, and urethra helps in storing and releasing the urine. Urodynamic testing is performed in the Urogynecology office and includes:
- Uroflowmetry: Measures the flow rate and volume of urine. Abnormal results indicate either a problem in the bladder muscles or block in urine flow.
- Post-void residual measurements: Measures the urine left in the bladder after urination
- Cystometriy test: Measures bladder filling including the volume of the urine the bladder holds and bladder pressure that causes the urge to urinate or leak.
- Leak point pressure measurements: Measures the bladder pressure that involuntarily causes urine to leak with coughing or pushing, during the cystometriy test
- Pressure flow study: Determines the urine flow rate and the mechanism through which the bladder, urethra and pelvic muscles coordinate in order to allow for voiding..
- Electromyography: Measures the electrical activity of the muscles and nerves in and around the bladder, urethral sphincter and pelvic floor muscles.
- Urethral pressure study: measures pressure generated by the urethral sphincter muscle to prevent leakage
- Video urodynamic tests: Captures pictures and videos of the filling and emptying of the bladder. Imaging is done either using X-rays or ultrasound.
Some of these tests are non-invasive while others require the insertion of a catheter into the bladder after giving local anesthesia.
You may feel a little discomfort when urinating for a few hours after the test.