A novel ultrasonic sensor suitable for producing 3D images of breast tissue more cheaply and safely than conventional technologies has been developed by British researchers.
The patented sensor relies on a pyroelectric material, capable of generating voltage when heated or cooled, to create an ultrasound image. The researchers said the new sensor creates images that are far less distorted than those obtained by currently used piezoelectric detectors, which are sensitive to the phase of the arriving ultrasound waves.
"We are evaluating this tool for imaging purposes with a view to looking at using it for screening should it prove to have the required sensitivity, specificity, patient acceptance and reproducibility of conventional mammography," said Lis Kutt from the Bristol Breast Care Centre Service of the North Bristol NHS Trust, who has worked on the project together with teams from the National Physical Laboratory, private firms Precision Acoustics and Designworks and University Hospital Bristol.
Commonly, X-ray mammography is used to perform breast cancer screening in the UK. The method, however, has its limitations. Many women consider it uncomfortable as it requires the breast to be compressed between the two plates of an X-ray machine. Moreover, due to the use of ionising radiation, the method cannot be used too often as it by itself could induce cancerous growth.
Frequently, physicians struggle to distinguish normal from potentially cancerous tissue in the 2D images captured by X-ray mammographs, which results in many false negatives and false positives. Conventional ultrasound imaging of breasts has been known for producing similarly limited results.
The newly developed sensor, believed to potentially offer a solution for overcoming the shortcoming of the existing methods, would work as part of a sophisticated system the researchers call ultrasound computed tomography.
To perform a scan, the patient’s breast would be placed in warm water between an ultrasound transmitter and receiver. Ultrasonic waves would be then sent through the breast and the amount of energy emerging would be measured by the prototype sensor.
By rotating the ultrasound transmitter and receiver 360 degrees around the breast, the system would be able to produce a 3D image of the breast tissue.
The engineers behind the project believe the method would not only be safer compared to X-ray-based mammography, but also cheaper and more accurate as the images would be easier to interpret.