A. Worthington

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During cell death, a series of structural changes occur within the cell. We have shown that cell ensembles and tissues undergoing structural changes associated with various cell death pathways can be detected using high-frequency ultrasound. In our effort to understand better the nature of backscatter from collections of cells (which emulate tissues), we(More)
It has previously been demonstrated in tissuemimicking phantoms and in tissue that envelope statistics of US backscatter are affected by changes in the scatterer properties [1–4, 32, 37]. At higher frequencies the wavelength of the US begins to approach the size of cells and cellular components and at this scale the envelope statistics of HFUS backscatter(More)
Multipoint foci have been synthesized by applying the pseudoinverse field conjugation method to a single ultrasonic transducer coupled to a polystyrene lens. The lens design is based on phased array calculations are then fabricated on a computer-controlled milling machine. The measured beam patterns from the lenses agree closely with the beam patterns(More)
Strongly focused large aperture transducers used in high-intensity focused ultrasound treatments are prone to manufacturing defects and degradation. Current methods for evaluating transducer quality measure only bulk physical changes of transducers. We have determined the pressure distribution at the transducer surface, using the angular spectrum method, to(More)
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