text: Mandy Fader, professor of continence technology at the University of Southampton, says their design has changed "very little" in 80  years.
  In the BBC News website's Scrubbing Up column, she criticises low investment from industry and "weak" regulation
  The Urology Trade Association says it is "simply incorrect" to say catheters have not improved in recent decades.
  The urinary catheter is a much-used, but little-discussed, device designed to drain the bladder.
  It is typically used in hospital to monitor how much urine patients have passed, or to make sure the bladder does not become too full.
  This can be for a matter of minutes - but some people are discharged with a catheter, and may continue to use one for months or even years.
  The tube is usually passed through the urethra and held in the bladder with a small balloon, though sometimes it is put in above the pubic bone via the abdomen into the bladder.
  It is connected to a drainage bag which is usually strapped onto the thigh or above the ankle. This - in turn - must be drained regularly.
  The catheter provides a site for bacteria to multiply and thrive, encased in a glue called "biofilm" which is resistant to detergent and antibiotics. This is a major source or urinary infection, blockages and leaks.
  It is estimated in the UK there are at least 90,000 people with long term urinary catheters, using them for three months or more.
  About one in five people who stay in hospital are fitted with a catheter, sometimes just as a matter of routine rather than requirement.
  Research suggests more than one in four urinary catheters inserted in A&E are unnecessary.
  This problem is being addressed in some hospitals.
  In a scheme to reduce Catheter Associated Urinary Tract Infections (CAUTI), five trusts in south London are working together to reduce harm in a scheme called "No Catheter, No CAUTI".
  The campaign, run by the Health Innovation Network,  aims to ensure catheters are not used inappropriately, and are removed promptly. It is hoped this will reduce these infections by 30% and, if it is successful, it will be rolled out across the NHS.
  Dr Adrian Hopper, the network's clinical director, said: "The general view is that CAUTI is the most common hospital acquired infection and vastly more common than MRSA and C-difficile which are the infections that everyone knows about."
  Prof Fader says there is growing evidence that catheters are over-used, but the main concerns  are about design and materials.
  She argues such a commonplace device should be a state of the art product, but concludes in her column that "the lowly catheter has changed very little in the last 80 years".
  And Prof Fader warns part of the problem lies with weak regulation, saying: "Unlike with new drugs, manufacturers do not need to show that any changes they make to catheters actually work on patients."
  She also criticises catheter manufacturers: "What's needed is for industry to wake up and invest more heavily in new catheter designs and... materials that resist infection."
  For too long the devices have been "easy money", she warns - with demand remaining high "without bothering with much innovation and improvement."
  But a spokesman for the UK health regulator, the Medicines and Healthcare products Regulatory Agency (MHRA), said there was a requirement that devices were designed and manufactured to minimise the risk of infection.
  He added: "We have no evidence at this time to suggest that urinary catheter materials used in the UK do not meet the requirements of the Medical Device Directive."
  Chris Whitehouse, chairman of the Urology Trade Association, called Prof Fader's comments "disappointing".
  "Any suggestion that catheters haven't improved in 80 years is simply incorrect.
  "Such an assertion ignores the efforts of manufacturers to develop catheters that meet patients' individual needs and that are safe, easy to use and discrete."
target: A leading researcher says industry must "wake up and invest more" in urinary catheters