M.Sc Thesis

M.Sc StudentGat Yonatan
SubjectScattering Tomography using Multiplexed X-Ray Sources
DepartmentDepartment of Electrical and Computer Engineering
Supervisor PROF. Yoav Schechner
Full Thesis textFull thesis text - English Version


X-ray Computed Tomography (CT) was introduced in the 1970s. CT has saved

many lives over the years, giving the opportunity to diagnose life-threatening medical

emergencies in a short amount of time. However, the radiation used in CT is known to

be ionizing and may increase the risk of developing cancer. A CT scan can take up to

half an hour, depending on the scanned body part and the patient’s physical properties. This leads to queues to obtain a CT scan. Shortening the acquisition time can result in

more patients being treated and scanned every day.

Irradiating by multiple X-ray sources simultaneously has been studied to reduce the

total acquisition time, thus mitigating voluntary and involuntary movement artifacts.

We suggest a multiplexing scheme using a motionless CT machine. A motionless CT

can support arbitrary source multiplexing. The reconstruction we propose exploits

scattered photons. We present a multiplexing code that balances the trade-off between

the total acquisition time and the reconstruction quality. We analyze and compare

how the number of multiplexed sources affects the reconstruction quality, compared

to the acquisition time. Using a physics-based forward model, we create simulations

which demonstrate how the number of acquisitions can be reduced by up to 80% while improving the reconstruction quality compared to previous methods .