[Preliminary clinical applications of asymmetric screen-film systems in chest radiography].
The physical imaging properties of asymmetric systems and a conventional system were evaluated by measuring characteristic curves, resolution properties and noise Wiener spectra. The potential clinical application of asymmetric screen-film systems was studied by evaluating the visibility of the anatomical structures and various types of abnormalities in comparison with those of a conventional screen-film system. The asymmetric systems showed a wider dynamic range than the conventional system. The resolution properties of asymmetric systems depend on the combination of front and back screens used. Chest radiographs obtained with asymmetric systems improved the visibility of the mediastinal area. The visibility of the lung field in the asymmetric systems was slightly inferior to that with the conventional system when the same tube potential was used. However, the image quality and visibility of various abnormalities showed greater improvement with the asymmetric systems when a lower tube potential was applied. We conclude that the selection of radiographic techniques and combination of screens are important for the clinical use of asymmetric systems.
Higashida
Y
Y
Department of Radiological Technology, Kumamoto University College of Medical Science.
Katsuda
N
N
Tochihara
S
S
Yoshioka
S
S
Bussaka
H
H
Tomiguchi
S
S
Takada
T
T
Matsumoto
M
M
Takahashi
M
M
Yoshida
A
A
D006801:Humans; D013902:Radiography, Thoracic / Q000295:instrumentation* / Q000379:methods; D013679:Technology, Radiologic; D014963:X-Ray Intensifying Screens