Skip to Main Content
 

Global Search Box

 
 
 
 

Files

File List


osu1186602293.pdf (1.95 MB)

ETD Abstract Container

Abstract Header

Data acquisition and reconstruction techniques for improved electron paramagnetic resonance (EPR) imaging

Ahmad, Rizwan
http://rave.ohiolink.edu/etdc/view?acc_num=osu1186602293

Abstract Details

2007, Doctor of Philosophy, Ohio State University, Electrical Engineering.
Electron paramagnetic resonance imaging (EPRI) is capable of measuring both endogenous and introduced free radical distributions in variety of biological systems. Despite the inherent potential, the broad use of EPRI is hampered by slow acquisition which can be the bottleneck for many biological applications where conditions may change over time. The objective of this work is to reduce the data acquisition time without degrading the reconstruction quality. First, we have modeled the data acquisition process for both spatial and spectral-spatial imaging in the form of Radon transform. Efficient-to-program expressions for Radon and inverse Radon transform for 2D, 3D, and 4D EPRI are derived. Second, we have proposed a method to uniformly distribute the data for both 3D and 4D EPRI which, from fewer projections, can generate reconstruction results which are better than those based on the existing nonuniform or partially uniform sampling techniques. The expected savings in the acquisition time offered by the suggested uniform sampling are 30% and 50% for 3D and 4D, respectively. In addition, we have also discussed existing uniform sampling methods and compared their performance with the suggested method using simulation and experimental data. Third, we have suggested a single-stage filtered backprojection reconstruction for 3D and 4D EPRI using the partial Radon transform for 4-fold acceleration. This substantial speed up further motivated us to reconsider the iterative reconstruction methods such as algebraic reconstruction which, despite having the superior performance in terms of reconstruction quality, have not been routinely used for 3D and 4D reconstructions due to their slow speeds. With the use of partial Radon transform, along with proper choice of interpolation type, the 3D iterative reconstruction time is reduced by more than 80%, which implies that a 64×64×64 image can be reconstructed from 150 projections using 100 iterations in approximately 10 minutes with ordinary contemporary computing resources. Further, the ability of the iterative methods to model EPR related constraints and to incorporate any other a priori information, such as nonnegativity, has also been demonstrated. Again, both simulation and experimental data are used to evaluate and compare the suggested reconstruction procedures.
Bradley Clymer (Advisor)
140 p.
EPR; EPRI; Oximetry; 4D Radon Transform; Filtered Backprojection; Fekete; ART; MART

Recommended Citations

Citations

  • Ahmad, R. (2007). Data acquisition and reconstruction techniques for improved electron paramagnetic resonance (EPR) imaging [Doctoral dissertation, Ohio State University]. OhioLINK Electronic Theses and Dissertations Center. http://rave.ohiolink.edu/etdc/view?acc_num=osu1186602293

    APA Style (7th edition)

  • Ahmad, Rizwan. Data acquisition and reconstruction techniques for improved electron paramagnetic resonance (EPR) imaging. 2007. Ohio State University, Doctoral dissertation. OhioLINK Electronic Theses and Dissertations Center, http://rave.ohiolink.edu/etdc/view?acc_num=osu1186602293.

    MLA Style (8th edition)

  • Ahmad, Rizwan. "Data acquisition and reconstruction techniques for improved electron paramagnetic resonance (EPR) imaging." Doctoral dissertation, Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=osu1186602293

    Chicago Manual of Style (17th edition)

osu1186602293
1,267
© 2007, all rights reserved.
This open access ETD is published by The Ohio State University and OhioLINK.