Peter Frey

Degree Type

Honors Capstone Project

Date of Submission

Spring 5-1-2009

Capstone Advisor

Dr. Andrew Darling

Honors Reader

Dr. Gustav Engbretson

Capstone Major

Biomedical and Chemical Engineering

Capstone College

Engineering and Computer Science

Audio/Visual Component


Capstone Prize Winner


Won Capstone Funding


Honors Categories

Sciences and Engineering

Subject Categories

Bioimaging and Biomedical Optics | Biomedical Engineering and Bioengineering


X-ray is a radiological tool utilized in healthcare institutions around the world to diagnose abnormalities such as bone fractures or the presence of foreign material within patients. The ability for healthcare providers to properly diagnose a problem is improved with advancements in the quality of radiological images. One way to improve image quality is to optimize the contrast range within a single image created by different attenuating characteristics in various types of tissue. In this study, I used a proof-of-concept prototype model of an x-ray attenuation system and an experimental protocol to examine its capacity to equalize x-ray beam signal values. A scout object consisting of different thicknesses of aluminum with the thickest section representing the most attenuated section and the target for equalization was used as a model of different types of tissue in a patient. The performance of the device and procedure was studied at various x-ray power levels and base acrylic thicknesses to represent anatomically relevant conditions. The different base acrylic thicknesses were used to represent standard attenuation in different sized patients. A statistical analysis was conducted using an unpaired t-test on the data results to identify whether the results are statistically significant and represent an improvement in image quality. The calibration equations developed to calculate the amount of iodinated contrast necessary at certain conditions were tested at intermediate levels to test performance under other conditions. The unpaired t-test was also conducted on these results. The analysis showed the exposure levels in each column were optimized to reduce the dynamic range of signal values.

Creative Commons License

Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License.



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