Investigation of priors mismatch in ultrasound tomographic reconstruction

Autor(es)

Cardona Cardenas, Diego Armando ; Furuie, Sergio Shiguemi ; Duric, N ; Byram, BC

• Tipo de documento: Artigo Científico
• Fonte: MEDICAL IMAGING 2018: ULTRASONIC IMAGING AND TOMOGRAPHY; v. 10580, p. 6-pg., 2018-01-01.

Resumo

Despite Ultrasound Tomography (USCT) not being ionizing and having low cost, it faces several challenges due to the physical nature of ultrasound interaction and propagation on the medium. One common strategy of diverse USCT-algorithms is to initialize with a-priori anatomical information of the region to be reconstructed, but the e ff ect of this initialization is not clear. To contribute in this topic, our work presents, on simulated medium, a study of how the modi fi cation in this initialization (value and area) a ff ects the USCT convergence and the generated image quality. In this study, the following were used: Distorted Born Iterative Method (DBIM) as the USCT-algorithm; a Matlab Toolbox (k-wave) for the forward problem; and the Algebraic Reconstruction Technique for the inverse problem. All simulated objects have equal density and attenuation, and the sound speed is varied between 1400 and 1680m/s. The initial attributes of Ob1, the largest object and with slowest velocity, are varied (c(ob1) +/- [0; 40; 80; 120] m=s and Area(ob1) +/- [0%; 15%; 25%]). In all simulations 64 transducers(100 kHz) uniformly distributed around the medium were used. The results, measured by Relative-Residual-Error and the Normalized-Root-Mean-Square-Error show, for all investigated areas, that convergence is better when the initialization velocity is set with higher than expected speed. Additionally, the RRE is higher for augmented area than for decreased area. For reconstruction quality, the NRMSE is also higher for augmented initial area than for small area. The investigation, based on simulations, suggests that when the contour of cold object is inaccurate, it is preferable to use smaller area such as its internal contour as prior region. (AU)

• Processo FAPESP: 16/10194-5 - Tomografia quantitativa baseada em ultrassom: aplicações em mamografia
• Beneficiário: Sergio Shiguemi Furuie
• Modalidade de apoio: Auxílio à Pesquisa - Regular