Mathias Fink Hot Topics presentation: Multiwave Approach to Elasticity Imaging for Cancer Detection
Acoustic imaging uses a phased array of ultrasound sources to focus a compression wave through the tissue. In his presentation, "Multiwave approach to elasticity imaging for cancer detection," Mathias Fink (Institut ESPCI, CNRS) shows how a time-reversal analysis technique of the data from an array of receivers produces a reconstruction of the transversed medium and an image of internal subject. The time-reversal analysis is made possible because the speed of sound in most soft medium is fairly uniform.
The process is effective with image resolutions on the order of 1 mm, but it is slow and limited to 50 frames/second. An improved method uses shear waves through the medium which travel slower, but show much higher sensitivity to changes in material density. The shear waves are produced by developing a traveling focused spot in the sample, this produces laterally traveling shear waves which are monitored by high speed detectors. The result is a much improved signal-to-noise ratio which allows for faster scan times and more detail, both of which lead to improved specificity for detection of density changes due to diseases like cancer.
Mathias Fink, a professor at ESPCI, is a member of the National Academy of Science in France and Director of the LOA. His research focuses on the propagation of waves in various complex media and the development of numerous instruments based on that research, including applications in medical imaging and therapy, non-destructive testing, underwater acoustics, seismology, telecommunications and instrumentation.