Ultrasound Imaging

Since the discovery of piezoelectricity in 1880 by Pierre Curie, ultrasonic waves could be deliberately transmitted, and their echoes detected by the same element. In 1940, ultrasonic imaging (Reflectoscopy) was first introduced for industrial use, and later for medical use in 1941[1]. Many advancements were developed for this modality, such as Doppler-ultrasonography for speed-of-flow measurements, High-Intensity Focused Ultrasound (HIFU) for therapeutic lesioning, Elastography, and more.

Resolution improvement in ultrasound imaging

Ultrasound imaging resolution is limited by its relatively large wavelengths. Medium inhomogeneities also contribute to resolution degradation, as ultrasonic image reconstruction (or focusing, as done in HIFU[2]) is performed under the assumption of a non-varying speed-of-sound in the medium. However, the speed-of-sound may vary significantly in many practical imaging scenarios (such as in biological tissue).

We are working to implement super-resolution methods from optical imaging in ultrasound imaging modalities to overcome the system's acoustic diffraction limit. By adapting these techniques, we aim to achieve higher-resolution imaging in ultrasound-based applications.

 

abberation figure

[1] Newman, P. G., & Rozycki, G. S. (1998). The history of ultrasound. Surgical clinics of north America, 78(2), 179-195.

[2] Kyriakou, A., Neufeld, E., Werner, B., Paulides, M. M., Szekely, G., & Kuster, N. (2014). A review of numerical and experimental compensation techniques for skull-induced phase aberrations in transcranial focused ultrasound. International journal of hyperthermia, 30(1), 36-46.

Previous group works:
Sommer, Tal I., and Ori Katz.“Pixel-reassignment in ultrasound imaging”. Applied Physics Letters 119.12 (2021): , 119, 12, 123701.