Ultrasonics Group
The Ultrasonics Group at UCL carries out research at the forefront of biomedical and therapeutic applications of ultrasound science.
Our Work
Ultrasound is revolutionising medicine with its innovative, non-invasive, and non-ionising therapeutic applications. Our research aim is to expand its potential, continually exploring new uses and advancing ultrasound-based therapies to improve patient care in clinical settings.
The group was founded in 1992 and has evolved since then. We have access to some of the best experimental facilities in the world, across a range of specialist laboratories at UCL and its partner hospitals. The group's own Ultrasonics Laboratory houses a wide range of state-of-the-art ultrasonic equipment.
We collaborate widely with other academic research groups, clinicians and industry and have created a multi-disciplinary, creative environment with researchers from a diverse range of backgrounds.
Our People
Principal Investigators | |
Professor Nader Saffari Professor of Ultrasonics |
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Dr. Pierre Gélat Associate Professor at the Department of Surgical Biotechnology |
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Dr. Reza Haqshenas Lecturer (Assistant Professor) in Therapeutic Ultrasound |
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Researchers (PhDs and Post Docs) | |
Mr. Amjad Khalil Surgical Specialist Registrar and PhD candidate |
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Arthur Jaccottet Research Assistant and PhD candidate |
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Daniel Silva PhD candidate |
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Parisa Abbasi PhD candidate |
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Navya Nayak PhD candidate View profile |
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Terence Seow PhD candidate View profile |
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Max Au-Yeung PhD candidate View profile |
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Benson Chen PhD candidate View profile |
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Our Ultrasound research projects
Histotripsy
When high-intensity, short-pulse sound waves are used in soft tissue, tiny gas bubbles form within the targeted tissue. These bubbles collapse in a process known as inertial cavitation, generating shockwaves that can disrupt cell membranes and even completely destroy cells. This technique, which uses cavitation to break down tissue, is called histotripsy. We are pioneering the use of ultrasound histotripsy for two different applications:
Cell Therapy
Ultrasound histotripsy can be used to mechanically fractionate soft tissues with a high degree of precision. We can create a cavity containing homogenized cytoplasmic liquid and cellular debris with minimal thermal damage to its periphery and with a clearly demarcated boundary. We are developing histotripsy combined with hepatocyte stem cell implantation as a novel method of reversing liver failure from genetic disease. We have shown that these cavities, and the fractionated lysate of cells within, will be a suitable environment for the engraftment and proliferation of implanted hepatocytes or their cell precursors for the treatment of liver disease.
CAR T-Cell Therapy
T-cells (a type of white blood cell) are extracted from the patient and genetically modified in the laboratory to display chimeric antigen receptors (CARs) on their surface. Once the modified T-cells are multiplied into millions in the lab, they are infused back into the patient. Ideally, the CAR T-cells will use their engineered receptors to identify and destroy cancer cells carrying the target antigen.
We are using histotripsy with CAR T-cells to improve penetration through physical barriers and to also enhance penetration through vascular barriers. We have shown that histotripsy can disrupt the extracellular matrix and make it easier for immune cells to infiltrate the tumour. This project is in collaboration with UCL Great Ormond Street Institute of Child Health and the Institute of Cancer Research.
Transcranial Ultrasound
Ultrasound is increasingly recognized as a promising tool for treating neurological disorders, including Alzheimer’s Disease (AD). Widely regarded as one of the safest and most frequently used diagnostic methods in modern medicine, ultrasound also holds therapeutic potential due to its ability to precisely target deep tissue with high spatial resolution, without the need for ionizing radiation or surgical incisions. Emerging evidence suggests that ultrasound achieves its modulatory effects by activating mechanosensitive ion channels in certain cells. This study investigates the use of ultrasound as a safe, non-invasive approach to enhance the ability of brain immune cells, known as microglia, to clear amyloid beta - a harmful protein strongly linked to Alzheimer’s Disease. This project is in collaboration with UCL Research Department of Neuroscience, Physiology and Pharmacology.
Ultrasound and Cell Mechanobiology
Low-intensity ultrasound is a non-invasive tool for stimulating cells in therapeutic applications, including neurodegenerative disorders (e.g., Alzheimer’s), musculoskeletal conditions (e.g., osteoarthritis), and cancer. While promising results have been observed, a deeper understanding of the mechanisms and pathways underlying ultrasound-induced cellular responses is crucial.
Our research integrates theoretical and experimental approaches to investigate the mechanobiology of cells under pulsed low-intensity ultrasound stimulation. Specifically, we examine how ultrasound-generated dynamic mechanical stresses drive cytoskeletal remodelling and influence key cellular functions, such as cell cycle regulation, growth, apoptosis, phagocytosis, and cell-cell/ECM adhesion. Our current focus includes models of microglia cells, breast cancer cells, and retinal pigmented epithelial cells.
Shear Wave Monitoring of Focal Ablation
Prostate cancer (PCa) constitutes a significant global healthcare concern, affecting an ever-increasing number of men worldwide. In the UK, PCa is the most common type of cancer and the second cause of cancer death in men. Despite this, methods of detecting and treating prostate cancer still have several important limitations (low specificity, high cost etc.).
Elastography techniques are emerging as a promising alternative to current PCa imaging methods. By assessing tissue stiffness, they have the potential to improve diagnostic accuracy and guide therapeutic interventions in real time. To materialise this potential, the UCL Ultrasonics Group has been conducting research to develop an innovative transurethral tool using shear wave elastography, named Transurethral Shear Wave Elastography (TU-SWE) probe. Previous simulation work has established the fundamental groundwork and demonstrated the feasibility and promise of the TU-SWE technique in the context of prostate cancer detection and treatment.
Ultrasound Imaging
Ultrasound Molecular Imaging
Ultrasound molecular imaging (UMI) is a cutting-edge diagnostic approach utilising US contrast agents functionalised with ligands that selectively bind to molecular markers on cells. Under US exposure, these agents enhance the signal from targeted cells, enabling real-time imaging of biological processes. UMI shows promise for early detection, characterisation, and monitoring of disease progression, such as cancer. Additionally, the use of US imaging, which is non-invasive and widely available, represents a significant advantage compared to other medical imaging modalities in studying cellular dynamics within their native tissue environment. Our research focuses on engineering phase-changing nanodroplets for imaging inflammatory immune cell models, specifically cytokine-activated macrophages. This work is conducted in collaboration with colleagues from UCL Chemistry and the UCL Institute for Women’s Health.
Quantitative Acoustic Cavitation Analysis
We investigate the physics of bubble nucleation and dynamics under ultrasound excitation, characterising these phenomena through both passive and active cavitation analysis. Our research includes in vitro and in vivo studies aimed at enhancing diagnostic precision and therapeutic applications. To support this, we have developed quantitative signal processing techniques using wavelet packet transform and machine learning. The outcomes of this work are integrated into WPT-Cavitation, a software package available on our GitHub page.
Computational Modelling and Numerical Methods
At the Ultrasonics Group, we carry out research and develop advanced computational models and high-performance numerical methods to address critical challenges in biomedical and therapeutic ultrasound. Our tools help:1) conduct mechanistic studies, 2) design, develop, and optimise novel treatments, and 3) enable treatment planning and prediction of the physical effects of ultrasound.
Mathematical Modelling
We develop multiscale, multiphysics models to analyse wave propagation in complex media and investigate multiphase phenomena. Our work on wave propagation includes modelling shear wave and acoustic radiation force elastography and solving the inverse problem for tissue characterisation. Our studies on multiphase interactions focus on ultrasound-mediated phase transitions such as sonocrystallisation, bubble nucleation, and acoustic cavitation, as well as the interaction of ultrasound with particles and drug carriers for targeted drug delivery. These models play a crucial role in characterising tissue before and after treatments, linking observed bioeffects to the underlying wave physics, and driving the development of novel imaging modalities and therapeutic interventions.
Numerical Methods and High-Performance Computing
To solve these complex models efficiently, we conduct research and develop advanced numerical methods using both commercial software (such as COMSOL Multiphysics, Ansys Fluent, and Abaqus) and in-house developed computational codes. A major focus of our work is on patient-specific treatment planning, which is essential for achieving precise tissue targeting while preserving healthy tissue. To this end, we leverage high-performance computing and develop fast numerical methods to solve full-wave propagation in the body in 3D. In particular, we employ the Boundary Element Method (BEM) and develop highly efficient and scalable numerical formulations and preconditioners for solving Helmholtz transmission problems in large, high-contrast domains and at high frequencies. To incorporate tissue inhomogeneity, we are researching novel hybrid methods that couple BEM with the Finite Element Method (FEM) and Volume Integral (VI) approaches.
Open-Source Tools and Libraries
Our research outputs are openly available via the Ultrasonics Group’s GitHub. One of our key contributions is OptimUS, a Python-based acoustic simulation toolbox designed to efficiently solve high-frequency linear acoustic wave propagation (Helmholtz transmission) problems. OptimUS accurately models piecewise homogeneous media in the frequency domain with minimal numerical pollution and dispersion, ensuring high-precision solutions.
Features of OptimUS:
- Implements advanced BEM formulations developed through our research
- Supports parallel computing and matrix compression, significantly reducing computational costs
- Provides a user-friendly Jupyter Notebook interface, with a growing library of examples in biomedical ultrasound and extensive documentation
- Packaged as a Docker image, allowing for seamless deployment and use across different operating systems
OptimUS has been tested across various applications in biomedical acoustics and ultrasound. However, it is designed as a versatile, general-purpose tool and can also be applied to fields such as sonar, room acoustics, outdoor acoustics, soundscaping and more.
Collaborate with us
OptimUS is a continuously evolving open-source project, developed in collaboration with experts in Scientific Computing from UCL Mathematics, University of Cambridge, and Pontificia Universidad Católica de Chile.
If you're interested in contributing or exploring our tools for your problems, feel free to contact us!
Sonic Womb
Acoustic noise can have profound effects on wellbeing, impacting the health of the pregnant mother and the development of the fetus. A better understanding of the fetal auditory environment is therefore critical to avoid exposure to damaging noise levels. Using anatomical data from MRI scans OptimUS was used to quantify the acoustic field inside the pregnant maternal abdomen. We obtained acoustic transfer characteristics across the human audio range and pressure maps in transverse planes passing through the uterus at 5 kHz, 10 kHz and 20 kHz, showcasing multiple scattering and modal patterns.
Prof. Brian Davidson
Prof. Gail ter Haar
Prof. David Attwell
Prof. John Anderson
Prof. Mark Emberton
Prof. Alberto Quaglia
Prof. Andreas Demosthenous
Prof. Marta Betcke
Prof. Umber Cheema
Prof. John Marshall
Prof. Timo Betcke
Prof. Alethea Tabor
Prof. Eric Jauniaux
Prof. Anna L. David
Prof. Julian Henriques
Dr. Hassan Rashidi
Dr. Andrew Melbourne
Dr. Anna Mufti
Dr. Elwin van ‘t Wout
Dr. Antonio Gomez
Dr. George Sideris-Lampretsas
Dr. Michael Booth
Dr. Dai Jang
Dr. Henry Lancashire
Dr. Shahin Heshmatifar
Mr. Saied Froghi MD
Many outstanding researchers have graduated from our Group or worked with us. Their contributions have advanced the field and shaped various industries, academia, and research institutions worldwide. Below is a selection of our alumni.
Prof. Eleanor Stride
Dr. Ki Joo Pahk
Dr. Antonio Gomez
Dr. Matheus de Andrade
Dr. Christopher Wright
Dr. David Sinden
Dr. Alex Livshics
Dr. AJ McCredie
Dr. Arnaud Lange
Dr. Sergey Martynov
Mr. Saied Froghi MD
Dr. Kamyar Firouzi
Dr. C.S. Ong
Dr. Ganesh Diwan
Laboratory and Software
Our laboratory is equipped with a range of ultrasound transducers, calibrated hydrophones, amplifiers, and 3D scanning frames with precision positioning systems. We also have access to the Verasonics HIFUPlex 3000 and 64 LE Research Ultrasound Platforms. Additionally, the lab includes comprehensive cell culture facilities (incubators, centrifuges, autoclave, biosafety cabinet, etc.) and a Leica THUNDER Imager Live Cell for advanced fluorescence and light microscopy.
Beyond our in-house capabilities, we utilise the departmental material characterisation and imaging suite (link), which houses multiple SEMs, a rheometer, an advanced Nikon micro-CT scanner, and a confocal microscope. For biological assays, we access shared biochemistry and molecular analysis facilities across UCL.
Software
We develop and maintain a diverse range of software for numerical simulations, acoustic signal processing, microscopy image processing, and ultrasound imaging, with many of our codes available on our GitHub page.
Contact Us
Professor Nader Saffari
n.saffari@ucl.ac.uk
Office 410
UCL Mechanical Engineering
Roberts Building, Torrington Place
London, WC1E 7JE
Queries about OptimUS?
You can reach out via the GitHub discussion page on the OptimUS repository. Alternatively, you can contact the principal investigators or the development team at optimusproject2017@gmail.com.
