Presentation
Can the physics-based full waveform inversion (FWI) outperform conventional elastography methods without relying on aggressive filtering that compromises spatial resolution? How can we handle its sensitivity to imprecise boundary conditions and the cycle-skipping issue? In this work, we introduce the FWI, commonly used in seismic imaging, to medical ultrasound time-harmonic elastography (THE).
Ultrasound elastography is a medical imaging modality that estimates tissue elastic properties, an important biomarker for disease diagnosis. In THE, mechanical waves are generated within the tissue and tracked using pulse-echo ultrasound imaging. Despite its practicality, low cost, and ease of use, ultrasound measurements typically produce noisier data compared to magnetic resonance imaging (MRI). Therefore, careful signal processing and robust inversion strategies are required.
Beyond its computational burden, FWI is often avoided due to sensitivity to uncertain boundary conditions and cycle skipping at high frequencies. We propose improved strategies to mitigate these limitations and validate the approach on both synthetic data and experimental phantom data acquired in our DSB Lab at the Department of Informatics. The performance is then compared with conventional processing methods.
Speaker
Mohamed Aziz Boukraa earned his PhD in Applied Mathematics from the University of Caen Normandy, France in 2021, with a thesis titled “Fading regularization inverse methods for the identification of boundary conditions in thin plate theory”. He then completed a postdoctoral fellowship through a collaboration between National Institute for Research in Digital Science and Technology (INRIA) in Paris and the French energy company EDF.
He is currently a postdoctoral research fellow at UiO under the DSTrain MSCA fellowship, working with the DSB group in the Department of Informatics on medical ultrasound elastography.
Program
11:30?– Doors open and lunch is served
12:00?– "Improved full-waveform inversion strategies for ultrasound time-harmonic elastography" by Mohamed Aziz Boukraa (Postdoctoral Fellow, Department of Informatics)
This event is open for all students, PhD candidates, postdocs, and everyone else who is interested in the topic. No registration needed.
About the seminar series
Once a month, dScience will invite you to join us for lunch and professional talks?at the Science Library. In addition to these, we will serve lunch in our lounge in Kristine Bonnevies house every Thursday. Due to limited space (40 people), this will be first come, first served.?See how to find us here.
Our lounge can also be booked by?PhDs and Postdocs on a regular basis, whether it is for a meeting or just to hang out – we have fresh coffee all day long!