The first breast screening system to use safe radio waves rather than radiation-producing X-rays is being successfully trialled.
The new scan, which took three years to develop, is being tested at Frenchay Hospital near Bristol.
The new system carries the same minor radiation risk as "speaking into a mobile phone at arm's length".
The scans also take less time than the conventional X-rays but produce an image which is just as clear.
Doctors say the machine does not expose patients to the risk of cancer, and a scan takes only six minutes.
Professor Alan Preece and Dr Ian Craddock began developing a breast-imaging device which used radio waves, unlike conventional mammograms, in 2003
Dr Craddock, from the university's electrical and electronic engineering department, said: "This new imaging technique works by transmitting radio waves of a very low energy and detecting reflected signals, it then uses these signals to make a 3D image of the breast.
"This is basically the same as any radar system, such as the radars used for air traffic control at our airports."
Mike Shere, associate specialist breast clinician at North Bristol NHS Trust (NBT) said: "Currently women are diagnosed in three ways; firstly by a clinician, then by using imaging such as mammography and ultrasound and lastly by a needle biopsy.
"The radar breast imaging system came to Frenchay Hospital in September this year and so far around 60 women have been examined using it.
"It takes less time to operate than a mammogram - approximately six minutes for both breasts compared with 30-45 minutes for an MRI, and like an MRI it provides a very detailed 3D digital image.
"Women love it as they compare it to a mammogram and find the whole experience much more comfortable."
The radar breast imaging system is built using transmitters and receivers arranged around a ceramic cup, which the breast sits in.
Theresa Thornton, one of 60 women examined using the new technology, was referred for a mammogram after finding lumps in her breast - subsequently found to be benign.
She told BBC News: "With the new technique its just a cup so you don't have to position yourself into it on certain angles, literally the cup just comes straight up to you, covers your breast and that's it.
"You don't have to get to the right angle , there is no squeezing on your breast at all."
The development team hope that, if the positive results continue, further trials will be scheduled for the next 12 months.
6 months ago