Small object contrast in AMBER and conventional chest radiography |
| |
Authors: | H G Chotas R L Van Metter G A Johnson C E Ravin |
| |
Affiliation: | Department of Radiology, Duke University Medical Center, Durham, NC 27710. |
| |
Abstract: | The ability of a commercially available scanning equalization system for chest radiography to render small object contrast in the lung-, mediastinum-, and subdiaphragm-equivalent regions of an acrylic chest phantom was quantitatively evaluated. Images from nine chest phantoms that represented a wide range of patient sizes and dynamic ranges of x-ray transmittance were analyzed. Subject contrast was measured with a photostimulable phosphor detector, and images were acquired in both equalized and nonequalized (conventional) imaging modes. Available subject contrast in the lung-equivalent region was 8%-15% lower in the equalized images compared with the nonequalized images in all phantoms (patient types); contrast in the mediastinum-, retro-cardiac-, and subdiaphragm-equivalent regions was 11%-63% higher in the equalized images, with the degree of improvement increasing as patient size and dynamic range increased. Images of each phantom were also acquired with the screen-film systems currently in use at the authors' institution, permitting an assessment of the relative performance (in terms of radiographic contrast) of these imagers with and without use of equalization. |
| |
Keywords: | |
|
| 点击此处可从《Radiology》浏览原始摘要信息 |
|
点击此处可从《Radiology》下载全文 |
|