Uroflowmetry or Urinary Flowmetry
Uroflowmetry is a medical test performed to determine the force of urine flow and the time required for urination, thereby enabling the diagnosis of urinary system disorders.
General Description
Uroflowmetry, also referred to as urinary flowmetry, is a diagnostic test that evaluates the time required to void and whether urination occurs with adequate force. Abnormal results may indicate the presence of urinary pathology.
Several parameters are measured during uroflowmetry:
- Average flow rate: calculated by dividing the volume of urine voided by the flow time.
- Flow time: the duration during which the patient is actively urinating.
- Voided volume: the amount of urine expelled, measured in milliliters.
- Voiding time: when there are no interruptions, it is equal to the flow time. In patients with interrupted urinary stream, it is shorter than the flow time.
- Maximum flow rate: the peak value reached by the urinary flow during voiding.
During urination, the urinary flow generates characteristic curves, as both force and volume vary throughout the process. Uroflowmetry allows observation of deviations from the standard pattern, mainly including: weak flow, low voided volume, delayed onset, or post-void dribbling.
This test helps determine bladder capacity, the strength of the urinary muscles, and the condition of the urethra and ureters.
When is it indicated?
Uroflowmetry is performed in patients with difficulty urinating, those who have noticed changes in their urinary habits, or those experiencing pain during voiding.
This test is used to diagnose conditions such as calculi, benign prostatic hyperplasia, tumors, overactive or neurogenic bladder (voiding dysfunction, incontinence, or post-void dribbling), cysts, or infections (cystitis, prostatitis, urethritis).
How is it performed?
The patient urinates into a device specifically designed for the test, similar to a toilet. During this time, the patient remains alone and uninterrupted to prevent flow interruption due to non-pathological causes. The patient may take as much time as needed.
The specialized device (a funnel-shaped apparatus connected to a collection container positioned on a measuring unit) records the required parameters (volume, presence of interruptions, total time) and converts them into a report represented graphically as a voiding curve.
Risks
Uroflowmetry poses no risk to the patient.
What to expect from uroflowmetry
Uroflowmetry is a simple, non-invasive, and painless test that does not require medication. It is an outpatient procedure after which normal activities can be resumed immediately.
At the medical center, the patient will remain in privacy until the bladder is completely emptied. It is recommended not to force urination or alter usual voiding patterns. Once completed, the specialist collects the data for subsequent analysis.
The duration of the test varies depending on each patient’s needs.
Specialties in which uroflowmetry is requested
Uroflowmetry is a diagnostic test performed within the specialty of Urology.
How to prepare
The patient should feel the urge to urinate at the time of the uroflowmetry, but not excessively. Therefore, it is recommended to void three hours prior to the test and then drink one glass of water approximately every half hour.
If the bladder is overly full upon arrival at the medical center, partial voiding is allowed, but not complete emptying.
