What Is Urodynamic Testing?
Urodynamic testing includes a series of diagnostic procedures that evaluate the lower urinary tract in terms of its health and function. Patients in the Staunton area can expect to undergo some form of urodynamic testing if they are experiencing frequent urinary tract infections, pain or burning with urination, hesitation with urination, frequency or urgency with urination, or trouble emptying their bladders.
Uroflowmetry, also called the Pressure Flow Study, is the first step in the urodynamic process. When a patient arrives for testing, they will be asked to have a full bladder. To start the testing the patient will urinate into the uroflowmeter, which commonly looks like a funnel or commode. This test measures the amount of urine, as well as how quickly the urine stream is exiting the body. Dr. Stisser adds, “it is very important for patients to note if they are feeling hesitation while trying to urinate, or if they feel like they are forcing their urine out, as this can effect test results.” The Pressure Flow Study is the standardized method of diagnosing a bladder outlet obstruction (BOO).
Immediately following the pressure flow study, a catheter will be inserted into the bladder to drain any remaining urine. This is called a postvoid residual measurement.
The bladder catheter is left in place to conduct the next test. The cystometrogram measures the pressure in and outside of the bladder during filling. The catheter is used to gradually inflate the bladder with fluid. As the bladder fills, the pressure inside the bladder is monitored. For this test, a second catheter is also inserted into the vagina or rectum. The sole purpose of the second catheter is to monitor the pressure outside the bladder. Cystometrograms can also be used to evaluate the bladder’s overall response to filling by looking at muscle and nerve activity.
A leak point pressure measurement can be helpful in the diagnosis of stress urinary incontinence, especially in women. This measurement is taken during the cystometrogram and does not require the patient to undergo additional tests. During the cystometrogram, the urologist may ask the patient to cough hard or laugh to simulate stress on the body.
The next step in the urodynamic process is to assess the function of the external urinary sphincter and pelvic floor muscles which are responsible for controlling the outflow of urine from the bladder. Electromyography measures the electrical activity of the sphincter and pelvic floor muscles while at rest, as well as during contraction and urination. The test can either be conducted using the sensors already attached to the catheters or with the placement of electrodes around the buttocks and perineum.
According to Dr. Stisser, “depending on the complexity of the patient’s condition, it may be necessary to also use video examination, which is simply called Video Urodynamic Study.” Fluoroscopy gives the urologist a three dimensional real-time x-ray image of the lower urinary tract which can be completed in conjunction with the cystometry and pressure-flow studies. The advantage of this is that the urologist can observe the body’s responses as they happen and visualize complications instead of solely relying on the standardized testing measurements.
For more information about our urodynamic testing or to schedule an appointment with a urologist, get in touch with our friendly staff here at Blue Ridge Urological Associates.