A new kind of ultrasound breast cancer scanner could help reduce the number of people who have unnecessary surgery.
Researchers at the National Physical Laboratory (NPL) have developed the technology as a way of creating more accurate ultrasound breast scans in order to cut the number of false positive results produced by current equipment.
The research, funded by NHS body the National Institute for Health Research (NIHR), used a technique for turning the ultrasound waves into heat energy before they are converted into electrical signals, to reduce the number of errors in the scan.
Ultrasound is already used for supplementary breast scanning and doesn’t carry the same potential risk of causing cancer as X-ray mammography, NPL’s project leader Dr Bajram Zeqiri told The Engineer.
‘The trouble is that you tend to get a significant degree of false positives, where you think there is something there and you do a biopsy and there isn’t, so you cause the patient lots of angst and trauma.’
These false positives are caused when a different parts of an ultrasound wave start to travel at different speeds as they encounter different tissue types.
When the wave hits the piezoelectric receiver — which converts vibrations into electrical signals — it assumes a corrugated shape that causes part of the signal to effectively cancel out another.
NPL’s solution was to use a material that absorbs the ultrasound and creates thermal energy. An attached polymer membrane then converts the heat via a pyroelectric reaction into an electrical signal that is unaffected by the wave’s corrugation.
NPL approached the University Hospitals Bristol NHS Foundation Trust — which then commissioned the research — after developing the basic scanning technology as a way of checking the safety of existing ultrasound scanning equipment.
The NIHR provided around £100,000 for a proof-of-concept study. The NPL is now hoping to receive more funding for a three-year project to develop the technology further.