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Full-Text Articles in Engineering
Three-Dimensional Image Reconstruction In Transcranial Photoacoustic Computed Tomography, Joemini Poudel
Three-Dimensional Image Reconstruction In Transcranial Photoacoustic Computed Tomography, Joemini Poudel
McKelvey School of Engineering Theses & Dissertations
Photoacoustic computed tomography (PACT) is an emerging imaging modality that exploitsoptical contrast and ultrasonic detection principles to form images of the photoacousticallyinduced initial pressure distribution within tissue. The PACT reconstruction problemcorresponds to an inverse source problem in which the initial pressure distribution is recoveredfrom measurements of the radiated pressure wavefield. A major challenge in transcranialPACT brain imaging is compensation for aberrations in the measured data due to the presenceof the skull. Ultrasonic waves undergo absorption, scattering and longitudinal-to-shear wavemode conversion as they propagate through the skull. To properly account for these effects, awave-equation-based inversion method should be employed that can …
Joint Reconstruction For Single-Shot Edge Illumination Phase-Contrast Tomography (Eixpct), Yujia Chen
Joint Reconstruction For Single-Shot Edge Illumination Phase-Contrast Tomography (Eixpct), Yujia Chen
McKelvey School of Engineering Theses & Dissertations
Edge illumination X-ray phase-contrast tomography (EIXPCT) is an emerging X-ray phasecontrast tomography technique for estimating the complex-valued X-ray refractive index distribution of an object with laboratory-based X-ray sources. Conventional image reconstruction approaches for EIXPCT require multiple images to be acquired at each tomographic view angle. This contributes to prolonged data-acquisition times and elevated radiation doses, which can hinder in vivo applications. In this dissertation, a new “single-shot” method without restrictive assumptions related to the object, imaging geometry or hardware is proposed for joint reconstruction (JR) of the real and imaginary-valued components of the refractive index distribution from a tomographic data …