Urodynamic Evaluations

Certain conditions such as pelvic floor disorders or other causes of urinary incontinence can truly put a damper on your day-to-day life. Fortunately, once the cause of the problem is discerned, there are treatments available. Rock Hill GYN & OB located in both Rock Hill and Fort Mill, SC, performs urodynamic evaluations in a safe and comfortable environment to assist with this very issue.

What is Urodynamics?

For those experiencing a urinary problem, it may be necessary to undergo urodynamic evaluations (UDS) which are a group of diagnostic test procedures to assess how the bladder and urethra are functioning with respect to storing and releasing urine. Generally speaking, urodynamic testing provides precise measurements using sophisticated instruments to assess the bladder’s ability to eliminate urine steadily and completely.

Issues that may prompt urodynamics include:

  • Uncontrolled urine leakage
  • Frequent urination
  • Painful urination
  • Sudden, strong urge to urinate
  • Difficulty starting a urine stream
  • Difficulty emptying the bladder completely
  • Recurrent urinary tract infections

Types of Urodynamic Evaluations

There are several different urodynamic tests that may be performed. Some of these tests yield results right away, while others may take a few days to process. The results of these tests help us determine the cause of your urinary problem so that the appropriate treatment can be determined. These tests help physicians determine if:

  • A patient is experiencing difficulty in starting a urine stream
  • The amount of effort put forth to maintain it
  • The stream is interrupted
  • There is residual urine left in the bladder after voiding


This test uses an uroflowmeter to measure the amount of urine and how quickly it is removed from the bladder. It provides a chart identifying changes in urine flow that shows the peak flow rate and the amount of time needed to achieve it. Abnormal test results occur if the bladder muscle is weakened or if there is an obstruction in urine flow.

Post-void Residual

When urinating is completed, there may be a small amount of urine left in the bladder. To find out how much is remaining (called a post-void residue) and to measure it, a catheter can be inserted into your bladder. A post-void residual of more than 200 ml (about half a pint) usually indicates a problem. If 100 ml (about half a cup) remains, additional testing may be indicated.


This test measures the amount of urine a bladder can hold, the amount of pressure that builds up as it stores urine, and how full it is when a patient feels an urge to urinate. It involves inserting a catheter into the patient’s bladder to fully drain it. A specialized catheter containing a pressure sensitive tube (cystometer) is then inserted to slowly fill the bladder with a saline solution and to measure pressure. An additional catheter is then inserted into the rectum to measure and record the pressure there as well. The procedure is also used to identify involuntary bladder contractions.

Leak Point Pressure Measurement

As a patient’s bladder is being filled during the Cystometry test, it can suddenly contract and force water out without warning. The cystometer records the pressure at the time the leak occurs. The cystometer’s reading indicates the type of bladder problem that a patient has. The procedure is also used to evaluate the sphincter muscles.

Pressure Flow Study

Following the cystometry test, the patient will be asked to empty his or her bladder so that the catheter can measure the pressures required to urinate. This study helps identify obstructions in the bladder outlet that is typical in men with prostate problems. While a bladder outlet obstruction is less common in women, it can occur with a condition such as a fallen bladder or infrequently after surgery for urinary incontinence.


Electromyography is used to measure nerve impulses and muscle activity in the urethral sphincter with sensors placed on the skin near the urethra and rectum. Occasionally, the sensors are on the urethral or rectal catheter. The recorded patterns of these impulses show whether the messages sent to the bladder and urethra are coordinated correctly.

Video Urodynamics

Urodynamic tests can be performed with imaging equipment such as X-ray or ultrasound to provide images of the bladder during filling and emptying. When x-rays are used, the bladder will be filled with a contrast medium instead of water to better visualize the bladder. The resulting images can help the physician better diagnose the patient’s problem.

After conducting your tests, we will schedule a follow-up appointment to go over the findings and lay out the next steps. Rest assured that there are several effective treatment options that can improve, manage, and fix urinary problems.

Schedule Your Appointment

Do not hesitate to be open about your symptoms and to ask questions or raise any concerns. We are here to help. Contact us to schedule an appointment with a member of our compassionate medical team.