Near-IR Device Diagnoses Bladder Dysfunction

A cell phone-size near-infrared device is as reliable as current invasive tests in determining bladder disease, according to a study by researchers at the University of British Columbia, Vancouver Coastal Health and the Child & Family Research Institute.

Published in the current issue of the International Journal of Spectroscopy, the study is the first to use near-infrared spectroscopy (NIRS) to investigate bladder disease in children. The new physiologic information gathered through NIRS could also advance treatment that tackles the root causes of urinary incontinence.

In this study of 37 healthy and symptomatic adults and children, researchers set a wireless NIRS device on the skin over the bladder, holding it in place with a strap. Differences in the amount of light shone through the skin to — and returning from — the bladder wall provided data on changing hemoglobin concentration, oxygen levels and blood volume.

A laser-powered instrument’s fiber optic cable and emitter detector interface attached over the bladder of a child, and a self-contained LED-powered device positioned for bladder monitoring. (Photo: ©2011 Andrew Macnab et al.)

The investigators found consistent patterns of normal oxygen availability and blood supply in the bladder muscle of healthy subjects during urination. Meanwhile, the patterns in children with symptoms due to voiding problems were quite different and matched patterns seen when blood flow or oxygen supply is inadequate for normal muscle function.

"Currently, diagnosing bladder dysfunction usually requires an invasive test that involves urethral and rectal catheter insertion to measure bladder pressure and urine output – a stressful and painful procedure that provides a limited amount of physiologic information," said lead author Andrew Macnab.

A previous study led by Macnab demonstrated the accuracy of noninvasive NIRS in diagnosing men with difficulty passing urine due to possible prostatic enlargement compared to invasive tests. Inclusion of children in the latest study further validates the merits of extending NIRS monitoring to children.

“Both adults and children like the device, and patients can be in a room remote from the researcher when they pass urine for the test, as the device can either store the data or transmit the results wirelessly to a computer in the next room. NIRS definitely constitutes a disruptive technology in the field of urology,” said co-author Lynn Stothers.

The technique should be particularly useful in studies involving children because its small size and ease of application causes no anxiety and doesn’t limit the participants’ movement or their ability to empty their bladder, said co-author Kourosh Afshar.

Urinary incontinence is a stigmatized and undertreated condition and often erroneously regarded as a "normal" part of early childhood and aging or a symptom of many other diseases. One-third of men and women ages 30 to 70 experience loss of bladder control that negatively impacts their quality of life. More than 1 million patients seek physician consults for this every year in the US alone. It also affects 53 percent of all long-term care residents, 25 percent of middle-aged women and 15 percent of all men 60 years and older.

For more information, visit: www.ubc.ca