2026-09-20T15:32:41Zhttps://dspace.mit.edu/server/oai/request

oai:dspace.mit.edu:1721.1/1227492021-07-05T14:03:20Zcom_1721.1_7582com_1721.1_7581col_1721.1_131023

Elfar Adalsteinsson. Arefeen, Yamin I.(Yamin Ishraq) Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science. Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science 2019-11-04T20:22:23Z 2019-11-04T20:22:23Z 2019 2019 https://hdl.handle.net/1721.1/122749 1124852667 Thesis: S.M., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2019 Cataloged from PDF version of thesis. Includes bibliographical references (pages 65-68). Magnetic Resonance Imaging (MRI) serves as a powerful and noninvasive medical imaging modality. It gives clinicians the ability to image a wide variety of physical parameters, control image content, and acquire images at arbitrary spatial orientations and resolutions. Recently, MRI has gained traction as a method to supplement the diagnostic capability of Ultrasound for pregnant mothers and fetuses. In particular, MR images dominated by T2 contrast, an intrinsic tissue parameter, give informative visualization for diagnosis. Traditional T2 weighted imaging techniques take on the order of seconds to minutes to acquire an image. However, due to the frequency and unpredictability of fetal motion, imaging techniques in fetal MRI must acquire a 2D image in under a second. T2-weighted fetal MRI techniques, called single shot acquisitions, achieve rapid imaging speed by acquiring all desired data after a single radio frequency excitation, but constraining all measurements to be taken after a single excitation produces images with spatially dependent blurring and poor contrast. As a result, many single shot techniques produce images with reduced diagnostic capability, in comparison to methods with longer acquisition times. This thesis aims to improve the diagnostic quality of T2-weighted single shot images. We incorporate the physical effects of rapid imaging into the image acquisition model and solve the resulting underdetermined system of equations using prior knowledge. We verify the efficacy of the techniques both in simulation and invivo adult brain experiments. Finally, we discuss how our proof of concent technique and results can be translated to the fetal imaging context. by Yamin I. Arefeen. S.M. S.M. Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science 68 pages eng Massachusetts Institute of Technology MIT theses are protected by copyright. They may be viewed, downloaded, or printed from this source but further reproduction or distribution in any format is prohibited without written permission. http://dspace.mit.edu/handle/1721.1/7582 Electrical Engineering and Computer Science. Acquisition and reconstruction techniques for improving rapid magnetic resonance imaging with applications in fetal imaging Thesis application/pdf 2019-11-04T20:22:22Z Publication Master EECS unknown unknown <Publication xmlns="https://www.openaire.eu/cerif-profile/1.1/" id="3c9b2a08-c70e-4145-b67c-50fb6d8eed15"> <Type xmlns="https://www.openaire.eu/cerif-profile/vocab/COAR_Publication_Types">http://purl.org/coar/resource_type/c_1843</Type> <Language>eng</Language> <Title>Acquisition and reconstruction techniques for improving rapid magnetic resonance imaging with applications in fetal imaging</Title> <PublishedIn> <Publication> </Publication> </PublishedIn> <PublicationDate>2019</PublicationDate> <Authors> <Author> <DisplayName>Arefeen, Yamin I.(Yamin Ishraq)</DisplayName> <Affiliation> <OrgUnit> </OrgUnit> </Affiliation> </Author> </Authors> <Editors> </Editors> <Publishers> <Publisher> <DisplayName>Massachusetts Institute of Technology</DisplayName> <OrgUnit /> </Publisher> </Publishers> <License>http://dspace.mit.edu/handle/1721.1/7582</License> <Keyword>Electrical Engineering and Computer Science.</Keyword> <Abstract>Magnetic Resonance Imaging (MRI) serves as a powerful and noninvasive medical imaging modality. It gives clinicians the ability to image a wide variety of physical parameters, control image content, and acquire images at arbitrary spatial orientations and resolutions. Recently, MRI has gained traction as a method to supplement the diagnostic capability of Ultrasound for pregnant mothers and fetuses. In particular, MR images dominated by T2 contrast, an intrinsic tissue parameter, give informative visualization for diagnosis. Traditional T2 weighted imaging techniques take on the order of seconds to minutes to acquire an image. However, due to the frequency and unpredictability of fetal motion, imaging techniques in fetal MRI must acquire a 2D image in under a second. T2-weighted fetal MRI techniques, called single shot acquisitions, achieve rapid imaging speed by acquiring all desired data after a single radio frequency excitation, but constraining all measurements to be taken after a single excitation produces images with spatially dependent blurring and poor contrast. As a result, many single shot techniques produce images with reduced diagnostic capability, in comparison to methods with longer acquisition times. This thesis aims to improve the diagnostic quality of T2-weighted single shot images. We incorporate the physical effects of rapid imaging into the image acquisition model and solve the resulting underdetermined system of equations using prior knowledge. We verify the efficacy of the techniques both in simulation and invivo adult brain experiments. Finally, we discuss how our proof of concent technique and results can be translated to the fetal imaging context.</Abstract> <Access xmlns="http://purl.org/coar/access_right" > </Access> </Publication>