Recursive ray tracing is applied for experimental time-of-flight projection data to achieve a resolution enhancement over the initial straight-ray reconstructed velocity image. Curved-ray reconstruction is performed using the dedicated simultaneous algebraic reconstruction technique (SART). Tomographic reconstructions from experimental data are compared to images obtained from simulated projection data for a refractive field mimicking the actual tissue-equivalent phantom. The simulation study adequately explains the macro-structural geometric distortion and loss of resolution in the straight-ray image due to refraction effects that are unaccounted for.
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Experiment was performed using the facilities of the Ultrasonics Signal Processing Laboratory at Purdue University.
