Development and evaluation of two novel instruments for X-ray imaging
Abstract/Contents
- Abstract
- The evolution of x-ray equipment has been stagnant because of its demanding design requirements, but clinical need for an advanced imaging technique has been continually growing. To contribute to hardware advances in the x-ray imaging devices, we designed and implemented innovative instruments by applying both mechanical and electrical principles. Herein, we explore two essential novel instruments for x-ray imaging: (1) a new electric motor for an MR-compatible x-ray tube and (2) a testing system for a high-energy x-ray detector. Because each imaging modality has different strengths and limitations, we are able to obtain more accurate medical images by combining at least two modalities. A hybrid x-ray/MR imaging system, leveraging the complementary advantages of both x-ray and MR imaging, is ideal for image guidance of catheters, guide wires, and prosthetic devices in real time. However, the performance of conventional x-ray tube motors is degraded when exposed to an external magnetic field, thus we developed and evaluated a new x-ray tube motor that can operate in the presence of the strong magnetic fields of an MRI machine. We further explored simulation models to improve the performance and dynamic characteristics of the new motor. High-energy x-ray imaging used in concert with low-energy x-ray imaging creates clearer and more accurate images. It is necessary to have a thicker scintillating phosphor layer to improve quantum efficiency for high-energy x-rays, but the spreading becomes more severe in that case. To resolve this issue, we can use a thick scintillating layer segmented by other thin layers (a.k.a. pixelated detector). Even though the pixelated detector prototype based on Sawant's design demonstrates relatively high detective quantum efficiency (DQE), both measured DQE and spatial resolution differ from corresponding expectations from theory and simulations. In order for the Monte Carlo method to accurately simulate the imaging performances, the characteristics of the basic pixelated unit must be understood. Therefore, we developed a new instrument to measure both light reflection and transmission distribution within the basic detector unit as a function of material, surface, and angle of incidence. Based on manufacturing procedures and the light distributions of the candidate samples, we also made valuable suggestions for a better, more profitable detector. We expect that our instruments will lead the next generation of diagnostic and therapeutic equipment to produce accurate diagnoses and efficient treatments for various disease states.
Description
| Type of resource | text |
|---|---|
| Form | electronic; electronic resource; remote |
| Extent | 1 online resource. |
| Publication date | 2015 |
| Issuance | monographic |
| Language | English |
Creators/Contributors
| Associated with | Shin, Mi Hye |
|---|---|
| Associated with | Stanford University, Department of Mechanical Engineering. |
| Primary advisor | Cutkosky, Mark R |
| Primary advisor | Fahrig, Rebecca |
| Thesis advisor | Cutkosky, Mark R |
| Thesis advisor | Fahrig, Rebecca |
| Thesis advisor | Pelc, Norbert J |
| Advisor | Pelc, Norbert J |
Subjects
| Genre | Theses |
|---|
Bibliographic information
| Statement of responsibility | Mi Hye Shin. |
|---|---|
| Note | Submitted to the Department of Mechanical Engineering. |
| Thesis | Thesis (Ph.D.)--Stanford University, 2015. |
| Location | electronic resource |
Access conditions
- Copyright
- © 2015 by Mi Hye Shin
- License
- This work is licensed under a Creative Commons Attribution Non Commercial 3.0 Unported license (CC BY-NC).
Also listed in
Loading usage metrics...