A5006746030- Ultrasound Imaging and Elastography
- Ultrasound and Hyperthermia Applications
- Photoacoustic and Ultrasonic Imaging
- Advanced MRI Techniques and Applications
- Electrical and Bioimpedance Tomography
- Hemodynamic Monitoring and Therapy
- Ultrasound and Cavitation Phenomena
- Medical Imaging Techniques and Applications
- Anesthesia and Sedative Agents
- Advanced X-ray Imaging Techniques
- Gallbladder and Bile Duct Disorders
- Gene Regulatory Network Analysis
- Thermal Regulation in Medicine
- Pediatric Hepatobiliary Diseases and Treatments
- Image and Signal Denoising Methods
- Manufacturing Process and Optimization
- Wireless Body Area Networks
- Genetics, Bioinformatics, and Biomedical Research
- Biomedical and Engineering Education
- Optical measurement and interference techniques
- Anesthesia and Neurotoxicity Research
- Respiratory Support and Mechanisms
- Biomedical Text Mining and Ontologies
- Microbial Inactivation Methods
- Central Venous Catheters and Hemodialysis
Imperial College London
2015-2024
Brighton and Sussex Medical School
2024
University of Michigan
2021
University of Edinburgh
2016
American Geophysical Union
2002
Hammersmith Hospital
1982-1990
Picker Institute Europe
1990
European Union
1987
Los Alamos National Laboratory
1987
British Nuclear Fuel Limited (United Kingdom)
1987
A method has been developed which can predict the appearance and properties of B-scan images. The theoretical basis for tissue models used, assumptions made in simulation concerning nature pulse-echo imaging, are discussed. key feature is Fourier domain synthesis model, permits convenient specification some statistical a randomly inhomogeneous scattering medium. Other characteristics that may be specified include ultrasonic pulse beam shapes, subsequent signal processing. Both initial model...
Randomized phased arrays can offer electronic steering of a single focus and simultaneous multiple foci concomitant with low levels secondary maxima are potentially useful as sources high intensity focused ultrasound (HIFU). This work describes laboratory testing 1 MHz random array consisting 254 elements on spherical shell radius curvature 130 mm diameter 170 mm. Acoustic output power efficiency measured for range input electrical powers, field distributions various single- multiple-focus...
Volunteers have undergone radio frequency hyperthermia in a magnetic resonance (MR) imaging system to investigate which of several possible MR parameters would be most convenient and sensitive use observe vivo temperature changes. Measurements were made for T1, T2, perfusion diffusion variations, although the number sequences needed at each meant that data points obtainable was limited. However, range studied (around 28-42 degrees C), changes both T1 coefficient observed agreed quite well...
A total of 116 small superficiald tumours have been treated by radiation alone, hyperthermia or and combined in a Phase I/II study. Most were metastases local recurrences adenocarcinoma breast but other histologies involved including melanoma. Hyperthermia was delivered predominantly microwaves, radiofrequency ultrasound methods also used. Rigorous thermal dosimetry, based on measurements from invasive multipoint thermocouple arrays, has shown that 58 per cent hyperthermal treatments reached...
Thermocouples are commonly employed for invasive temperature measurement in clinical hyperthermia. The effect of thermal conduction along the leads on accuracy thermocouples an inhomogeneous field has been examined. These effects modelled as a convolution with suitable point spread function and most cases errors produced equivalent to mispositioning thermocouple by less than 1 mm. functions T-type have measured, agree theoretical predictions that reduced if copper leg is replaced manganin. A...
A new type of low-profile applicator is described giving efficient power transfer to tissue with low leakage. It consists a resonant element spaced from ground plane by low-loss material having high relative permittivity and some permeability. This combination covered similar which can be placed in direct contact the heated, or separated it water bolus as required. Laboratory measurements using phantom materials show that these applicators are well matched produce defined relatively uniform...
A computer simulation of tissue heating is used to examine the pattern produced by a focused ultrasound transducer scanned over tumor. It shown that, large area required give preferential at depth and not given path focal volume. The effect varying with time pulsing or scanning investigated using an estimate thermal dose which takes into account the. nonlinear dependence heat damage on temperature, it found that temperature fluctuations tend reduce therapeutic ratio so should be avoided....
Abstract Systems Biology is an approach to biology and medicine that has the potential lead a better understanding of how biological properties emerge from interaction genes, proteins, molecules, cells organisms. The aims at elucidating these interactions govern function by employing experimental data, mathematical models computational simulations. As inherently multidisciplinary, education within this field meets numerous hurdles including departmental barriers, availability all required...
Hospitals nowadays have to serve numerous patients with limited medical staff and equipment while maintaining healthcare quality. Clinical pathway informatics is regarded as an efficient way solve a series of hospital challenges. To date, conventional research lacks mathematical model describe clinical pathways. Existing vague descriptions cannot fully capture the complexities accurately in pathways hinders effective management further optimization pathways.Given this motivation, paper...
The overlaying rib cage is a major hindrance in treating liver tumors with high intensity focused ultrasound (HIFU). problems caused are overheating of the ribs due to its ultrasonic absorption capability and degradation distribution target plane. In this work, correction method based on binarized apodization geometric ray tracing approach was employed avoid heating ribs. A detailed calculation focus plane undertaken quantify effect HIFU beam generated by 1-MHz 256-element random phased...
Therapeutic ultrasound technologies using microbubbles require a feedback control system to perform the treatment in safe and effective manner. Current utilize microbubble's acoustic emissions adjust parameters. Typical systems use two separated transducers: one for transmission other reception. However, separating transmitter receiver leads foci misalignment. This limitation could be resolved by arranging stacked configuration. Taking advantage of an increasing number short-pulse-based...
Abstract Parallel acquisition of Magnetic Resonance Imaging (MRI) has the potential to significantly reduce scan time. SENSE is one many techniques for reconstruction parallel MRI images. A generalized algorithm and theoretical background presented. This can be used any acceleration factor between 2 8, Phase Encode direction (Horizontal or Vertical), with without Regularization. The user select a particular type GUI based implementation also given. Signal‐to‐noise ratio, artefact power, g...
Abstract Experimental validation of a synthetic aperture imaging technique using therapeutic random phased array is described, demonstrating the dual nature and therapy such an array. The transducer capable generating both continuous wave high intensity beams for ablating tumor low ultrasound pulses to image target area. Pulse-echo data collected from elements obtain B-mode images targets. Since arrays are optimized only with concave apertures having f-number large directive often coarsely...
Abstract Parallel MRI has brought forward new applications by reducing the scan time in MR image acquisition. The acceleration is achieved number of phase encode steps acquired during acquisition thus giving aliased images. Sensitivity encoding (SENSE) a widely used method to unwrap One major problem noise amplification process reconstruction as well artifacts, which may arise process. Regularization an important tool reduce this (measured geometry factor [g‐factor]) and but it...
In exploring adjuvant therapies for head and neck cancer, hyperthermia (40–45 °C) has shown efficacy in enhancing chemotherapy radiation, as well the delivery of liposomal drugs. Current treatments, however, struggle to reach large deep tumors uniformly non-invasively. This study investigates feasibility delivering targeted uniform into tissue using a non-invasive ultrasound spherical random phased array transducer. Simulations 3D patient-specific models thyroid oropharyngeal cancers...
Ultrasound-driven microbubble (MB) activity is used in therapeutic applications such as blood clot dissolution and targeted drug delivery. The safety performance of these technologies are linked to the type distribution MB activities produced within area, but controlling monitoring vivo real time has proven be difficult. As pulses often milliseconds long, currently requires a separate transducer passive reception mode. Here, we present simple, inexpensive, integrated setup, which focused...