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dc.contributor.advisorSarıtaş, Emine Ülkü
dc.contributor.authorSarıca, Damla
dc.date.accessioned2017-06-12T07:42:35Z
dc.date.available2017-06-12T07:42:35Z
dc.date.copyright2017-06
dc.date.issued2017-06
dc.date.submitted2017-06-09
dc.identifier.urihttp://hdl.handle.net/11693/33203
dc.descriptionCataloged from PDF version of article.en_US
dc.descriptionThesis (M.S.): Bilkent University, Department of Electrical and Electronics Engineering, İhsan Doğramacı Bilkent University, 2017.en_US
dc.descriptionIncludes bibliographical references (leaves 45-48).en_US
dc.description.abstractMagnetic Particle Imaging (MPI) is a high contrast tracer imaging modality with applications such as stem cell tracking, angiography and cancer imaging. In MPI, a time-varying magnetic field called the drive field is applied, and the magnetization response of superparamagnetic iron oxide nanoparticles (SPIOs) is recorded. The signal from these nanoparticles is at both drive field frequency and its higher harmonics. However, due to simultaneous excitation and signal reception, the direct feedthrough contaminates the nanoparticle signal at the fundamental harmonic. The direct feedthrough signal can be eliminated using a high-pass filter, where the effect of this filtering has been shown to be a DC loss in image domain. Reliable x-space image reconstruction can then be achieved via enforcing positivity and continuity of the image. However, low SPIO concentrations and/or hardware constraints can further limit the usable signal bandwidth to only a few harmonics. Under low bandwidth signal acquisitions, the loss of higher harmonics results in blurred images after regular x-space reconstruction. This thesis proposes an iterative x-space reconstruction method that recovers not only the lost fundamental harmonic but also the un-acquired higher harmonics for low-bandwidth acquisitions. Proposed method converges to the ideal (i.e., high bandwidth) MPI image in 3-4 iterations. In extensive simulations that incorporate measurement noise and nanoparticle relaxation effects, the proposed method displays improved image quality with respect to the regular x-space reconstruction scheme, with at least 6 dB improvement in peak signal-to-noise ratio (PSNR) metric. Finally, the proposed method is also demonstrated with imaging experiments on an in-house MPI scanner.en_US
dc.description.statementofresponsibilityby Damla Sarıca.en_US
dc.format.extentxiii, 48 leaves : charts (some color) ; 29 cmen_US
dc.language.isoen_USen_US
dc.rightsinfo:eu-repo/semantics/openAccessen_US
dc.subjectMagnetic Particle Imagingen_US
dc.subjectImage Reconstructionen_US
dc.subjectLow-Bandwidth Signal Acquisitionen_US
dc.titleLow-bandwidth image reconstruction for magnetic particle imagingen_US
dc.title.alternativeManyetik parçaçık görüntüleme için düşük bantlı görüntü geriçatımıen_US
dc.typeThesisen_US
dc.departmentDepartment of Electrical and Electronics Engineeringen_US
dc.publisherBilkent Universityen_US
dc.description.degreeM.S.en_US
dc.identifier.itemidB155727
dc.embargo.release2018-06-09


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