Urine Stream Shape May Help Diagnose Prostate Problems
New research from the UK suggests that the shape of a man's urine stream may help diagnose prostate and urinary problems. The researchers hope their findings will lead to a solution that helps male patients monitor their urine flow rate, an important diagnostic measure, more easily at home.
A paper published in PLoS ONE on 16 October, by co-author Martin Knight from Queen Mary, University of London, and colleagues, describes the first study to analyze the biophysics of a man's urine flow as a potential diagnostic tool.
The team describes how they developed a computational fluid dynamics model of "capillary-waves in free-jet flows" to analyze the characteristic shape of a man's urine flow as it exits the urethra:
"The characteristic shape is due to the surface tension in the urine and the elliptical shape of the urethra," explains Knight, a medical engineer and expert in biomechanics from Queen Mary's School of Engineering and Materials Science, in a press statement.
"The computer model matched perfectly to experiments in the laboratory and also with video data of human volunteers. There was an excellent correlation between the shape of the urine stream and the urine flow rate," he adds.
Knight says they started looking at the idea when a team of urologists asked the University if they could find a way to measure urine flow rate non-invasively. Perhaps even in a way that could be done easily at home, where patients' flow rates are likely to be more typical than when measured in the hospital.
For their study, the team invited 60 healthy volunteers and 60 patients to take part in a test to see whether measuring the shape of their urine stream could be used to predict the rate of urine flow.
They found that a simple measure of the characteristic shape of the flow pattern could accurately predict the maximum urine flow rate, an important measure in the diagnosis of urinary problems like those linked to prostate enlargement.
They also found that for the patients, "the relationship between shape and flow rate suggested poor meatal [the orifice of the urethra] opening during voiding".
Figures from Prostate Cancer UK suggest two in five men over the age of 50 and three quarters of those in their 70s have symptoms that could be due enlarged prostate.
Knight says:
"The current techniques, although very accurate, are difficult or expensive to use reliably outside of the clinic. This new approach may therefore represent a useful solution to this important medical engineering problem, allowing men to easily monitor their urine flow rate."