| Achoimre: | The high acoustic intensity in HIFU often results in production, either through acoustic cavitation or boiling. these are believed to be a primary contributor to tissue . Some HIFU protocols rely on the evidence of cavitation a strong indicator of tissue lesions. Cavitation is normally with hyperechoic regions ('bright up') in ultrasound mode image feedback but other events may cause as well, so spectral detection methods are of increasing interest in early and robust detection of activity. It is also useful to distinguish it from thermal of bubbles. To estimate the spectrum whilst still good spatial localization requires methods which work short time series of data, so methods based on the Fourier are not applicable,. The method in this paper uses statistical methods, (collectively described as ARMA ) to analyse the spectral data at high spatial resolution so changes can be more easily identified. It applies an adaptive which estimates both the best model type and order. The is assessed using a simulati on of data from cavitation, the applied to detect cavitation following HIFU in ex-vivo liver. Thermal bubble generation is monitored using a frequency hydrophone. ©2008 IEEE.
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