Uroflowmetry
You pass urine into a special funnel with a comfortably full bladder, and the machine records the rate and pattern of flow. Combined with an ultrasound measurement of residual urine, it gives an objective picture of how obstructed you are. It is completely non-invasive and takes minutes.
Urodynamic study
A more detailed test using fine catheters to measure pressure inside the bladder and abdomen while the bladder is filled. It distinguishes a bladder that is obstructed from one that is simply weak — a distinction that decides whether prostate surgery will help you or not.
- Before surgery when symptoms and flow findings disagree
- Incontinence that is unclear or has failed treatment
- Neurogenic bladder from spinal, diabetic or neurological disease
- Children with voiding problems
- After failed previous surgery
Preparing for the test
Come with a comfortably full bladder and your medication list; some bladder medicines may need pausing beforehand, which the clinic will tell you in advance. Bring your voiding diary if you have been asked to keep one. Mild burning for a day after a urodynamic study is common and settles with fluids.
Uroflowmetry / Urodynamic Study — common questions
Is uroflowmetry painful?
Not at all. You simply pass urine into a measuring device in private.
Why is a urodynamic study needed before prostate surgery?
Because a weak stream can come from a weak bladder rather than an obstructing prostate. Operating on the prostate does not help a weak bladder, and the test prevents that mistake.
How long does urodynamics take?
Usually 30 to 45 minutes including preparation and explanation.
Do I need to stop my medicines before the test?
Some bladder medicines are paused for a few days. You will be given specific instructions when the test is booked.
Reviewed by Dr. Kinjal Banerjee, MBBS, MS (General Surgery), DNB (Urology) — Urologist, Renal Transplant & Robotic Surgeon, Faridabad. This page explains uroflowmetry / urodynamic study in general terms; your own treatment plan depends on your reports and examination.