• Before and after the tests

You don’t need to do much to prepare for these tests, but you will need to give a urine sample<

first to make sure you don’t have an infection. Also, check with your doctor if you need to stop taking any medications before the test. Urodynamics includes various tests that are used to measure the changes in pressure and filling in the bladder and urethra. These tests take about 30 minutes. If you have a urinary infection, you’ll need to take antibiotics before you can have the test. If you are pregnant, please call the clinic right away. Your urodynamics evaluation may need to be postponed. Drink enough water so that you arrive at your appointment with a full bladder. (If you have a Foley catheter, there is no need to drink more water than normal.)

While the insertion of catheters can feel uncomfortable or produce a minor burning sensation

the process is generally not painful.You may experience mild irritation or slight blood in your urine for a short period after the test. An antibiotic may be prescribed for 1 or 2 days to prevent infection, but not always. People with signs of infection—including pain, chills, or fever—should call their healthcare provider immediately.

• Uroflowmetry

An uroflowmeter automatically measures the amount of urine and the flow rate. You may be asked to urinate privately into a toilet that contains a collection device and scale. This equipment creates a graph that shows changes in flow rate from second to second so your doctor can see the peak flow rate and how many seconds it took to get there. Results of this test will be abnormal if the bladder muscle is weak or urine flow is obstructed. Typically in woen, urine flow runs from 15 ml to 21 ml per second. Mean flow rate in men ranged betwwen 21 ml/s to 12 ml/s.

• Post void Residual Measurement

After you have finished urinating, you may still have some urine, usually only an ounce or two, remaining in your bladder. To measure this post void residual, your doctor can measure the post void residual with a catheter or an ultrasound equipment. Less than 50 mL PVR is considered normal. Up to 100 mL PVR may be acceptable. A post-void residual of 150 mL or more is often a sign that the bladder is not emptying completely.

• Cystometric Test or Cystomanometry

A cystometrogram (CMG) measures how much your bladder can hold, how much pressure builds up inside your bladder as it stores urine, and how full it is when you feel the urge to urinate. If you need a cystometry test, you may be asked to lie down, sit, or stand. During the test, a thin tube (catheter) will be gently placed into your urethra with a numbing gel to make it more comfortable. Another catheter may be placed into the rectum or the vagina to record pressure into your belly (abdominal pressuer). During the time of filling, you will be asked how your bladder feels and when you feel the need to urinate. You may be asked to cough or strain during this procedure to see if the bladder pressure changes. With this test involuntary bladder contractions can also be identified which is correponding of an overactive bladder. Normal functional bladder capacity in adults ranges from approximately 300 to 500 mL but most people feel the need to urinate when it’s holding around 200 mL.

• Urethral Profilomery Test

The UPP measures the intraluminal pressure along the length of the urethra and is part of the tests that form urodynamic evaluation.. A specialized catheter (often equipped with pressure transducers) is gently inserted into the bladder. As the catheter is steadily withdrawn at a controlled rate, the equipment plots a topographic curve of pressure measurements from the bladder neck down to the external opening. UPP help the to evaluate your sphincter muscles wich could be weak (intrinsic sphincter insufficiency) or urethral hypertony. The normal value of urethral closure pressure can be derived by the formula 110-age or 92 – age 

• Leak Point Pressure Measurement

While your bladder is being filled for the CMG, it may suddenly contract and squeeze some water out without warning. The manometer will record the pressure at the point when the leakage occurred. This reading may provide information about the kind of bladder problem you have. You may also be asked to apply abdominal pressure to the bladder by coughing, shifting position, or trying to exhale while holding your nose and mouth. These actions help the to evaluate your uretral sphincter muscle wich could be weak (intrinsic sphincter insufficiency) or urethral hypertony. 

• Pressure Flow Study

After the CMG, you will be asked to empty your bladder. The catheter can measure the bladder pressures required to urinate and the flow rate a given pressure generates. This pressure flow study helps to identify bladder outlet obstruction in men who may experience with prostate enlargement. Bladder outlet obstruction is less common in women but can occur with a fallen bladder or rarely after a surgical procedure for urinary incontinence. Most catheters can be used for both CMG and pressure flow studies. Some people may find it difficult to empty their bladders with a catheter or with another person in the room. Don’t be embarrassed if this happens. While you might feel your healthcare provider inserting the catheter into your urethra, the test doesn’t hurt.

• Electomyography

Electromyography uses special sensors to measure the electrical activity of the muscles and nerves in and around your bladder and sphincters. During a urodynamic EMG test, small electrode patches are placed near the urethra and rectum. The physician then asks the patient to contract and release the muscle several times to test the area. The electrode sends signals to contract the muscle and records the response, using a numerical value to show functionality. The patterns of the nerve impulses show whether the messages sent to your bladder and pelvic floor muscles are coordinating correctly.