View article

To assess the malignancy and progression of a tumour, parameters such as the size and number density of the microvessels are expected to be important. The optical absorption due to the blood that fills the microvessels can be visualised by optoacoustic imaging (OA). We have previously reported that increasing the inhomogeneity of absorption within a large absorbing volume produces evidence of reduced acoustic coherence which results in improved contrast and boundary detectability. Here we propose to take advantage of the expectation that the detailed nature of the inhomogeneity should influence the frequency spectrum of the OA signal. The overall aim of this work is to determine whether an analysis of the frequency spectrum of the emitted optoacoustic signal can be used to determine the scale of this absorption inhomogeneity, in particular parameters such as the characteristic size and separation of the …