Seminar Series

Non-invasive Breast Cancer Screening Technology: Digital Image Elasto Tomography (DIET)


Ph.D. Student Jessica Fitzjohn


Department of Mechanical Engineering, University of Canterbury

Time & Place

Tue, 14 Dec 2021 13:00:00 NZDT in E12, Engineering Core


Breast cancer is the most common cancer in women (25%) and a major health issue worldwide. Annual diagnosis is estimated at over 1 million and it causes over 400,000 mortalities. It is one of the most expensive cancers costing over $75 million in New Zealand, not including over $40 million spent running Breast Screening Aotearoa. Early detection reduces mortality and associated cost due to increased treatment options.

X-ray mammography is considered the gold standard for breast screening; however, this technique remains controversial due to painful breast compression, radiation exposure and poorer performance of mammography in dense breasts. Digital Image Elasto Tomography (DIET) is an alternative breast cancer screening technology, which is affordable, portable, comfortable and safe for all ages. It involves capturing images of steady state vibration of the breast, which are converted to displacement data for over 14,000 reference points using surface volume and optical flow techniques. Analysis of surface motion allows assessment of underlying tissue properties and, utilising the high contrast in elastic properties between cancerous and healthy tissue (400~1000%), can provide diagnostic insight.

One diagnostic method proposed uses a model similar to Rayleigh Damping to model viscous damping in the breast. Using clinical data for 26 breasts, comparison of one model coefficient in different breast segments provides an unbiased, generalisable diagnostic method with sensitivity and specificity of 76.9%, similar to asymptomatic mammography. Different breast segmentation configurations were tested to ensure robustness and bootstrapping produced a receiver operator characteristic (ROC) curve with area under the curve (AUC) of 0.81 and optimal sensitivity and specificity of 77% and 72%, respectively.      

The DIET technology has the ability to increase equity in breast screening by allowing women of all ages to be safely screened, increasing access to screening for women who live rurally and increasing comfort during screening to encourage higher participation in screening programs, which is currently below 70%.

All are Welcome!


Jessica Fitzjohn


Supervisor: Distinguished Professor Geoff Chase