Quantative analysis of fluctuations in biological tissues via multispectral photoacoustic imaging

Abstract

A method is disclosed for processing photoacoustic images, this method including: obtaining a time series of images of a sample, the images being acquired by a photoacoustic imaging system at Mx excitation-pulse wavelengths, with N images acquired per wavelength; performing multispectral spatio-temporal filtering via singular value decomposition applied to all of the N*Mx acquired images so as to obtain N*Mx filtered images; for each wavelength, computing a filtered variance image based on the N filtered images, a pixel of coordinate r in the filtered variance image being equal to the variance of the distribution of the values of pixels of same coordinate r in the filtered images obtained for this wavelength; and correcting the filtered variance image by subtracting a variance of the residual electronic noise after the multispectral spatio-temporal filtering has been performed, the noise being produced by the sensors of ultrasonic waves of the photoacoustic imaging system.