| Autor: |
T.T. Huang, Chuan-Jong Tung, C.H. Yang, H.Y. Tsai, I.J. Chen, M.Y. Shi |
| Rok vydání: |
2007 |
| Předmět: |
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| Zdroj: |
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. 580:602-605 |
| ISSN: |
0168-9002 |
| Popis: |
In the present work, a contrast-detail phantom was used to study the image quality and the radiation dose for digital X-ray imaging systems. The phantom consists of a 265 mm (H)×265 mm (W)×10 mm (D) acrylic sheet with drilled holes of various depths and diameters. At each setting of exposure techniques, three images were taken and evaluated subjectively by three independent radiologists. The average image quality figure (IQF) was then calculated. In addition, a computer program was developed to evaluate objectively the same images. This program, written in MATLAB, was based on a statistical method with variance analysis of the image pixels. Corrections of the parallax effect were made. Results showed that the computer program proved more sensitive than the radiologists. In addition to image analyses, the entrance surface dose (ESD) was measured using the Harshaw thermoluminescent dosimeters TLD-100H. Two 75 mm-thick acrylic slabs were used with the contrast-detail phantom in between. Optimization analyses on the image quality and the radiation dose were performed. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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