source: © 2013 Physics in Medicine & Biology
Model-based optoacoustic inversion methods are capable of eliminating image artefacts associated with the widely adopted back-projection reconstruction algorithms. Yet, significant image artefacts might also occur due to reflections and scattering of optoacoustically-induced waves from strongly acoustically-mismatched areas in tissues. Herein, we modify the model-based reconstruction methodology to incorporate statistically-based weighting in order to minimize these artefacts. The method is compared with another weighting procedure termed half-image reconstruction, yielding generally better results. The statistically-based weighting is subsequently verified experimentally, attaining quality improvement of the optoacoustic image reconstructions in the presence of acoustic mismatches in tissue phantoms and small animals ex-vivo.  [Read more…]
Fig. 5 Tomographic reconstructions of the zebrafish obtained with the IMMI algorithm (a)–(c), with the statistically-based weighted IMMI algorithm (d)–(f) and with the half-time weighted IMMI algorithm (g)–(i). The reconstructions are done by considering all the measuring locations in a full-view scenario (a), (d), (g), or for a limited-view case by taking measuring locations along an arc covering an angle of 270° (b), (e), (h) or 180° (c), (f), (i). For the limited-view case, the centre of the detection arc is located above the images. (j) and (k) show a comparison of the reconstructions obtained with the IMMI algorithm and the statistically-based IMMI algorithm for several slices. The area A is taken as the as the area inside the dashed circumferences and the weighting parameter ω = 1 for all cases.