Digital chest radiography with a large image intensifier. Evaluation of diagnostic performance and patient exposure.
A digital system for chest radiography based on a large image intensifier was compared with a conventional film-screen system. The diagnostic performance was evaluated with special reference to the digital monitor images with a modified version of receiver operating characteristic (ROC) analysis--free response ROC (FROC) analysis--on a chest equivalent phantom. Measurements of spatial resolution and energy imparted were also performed. The detectability of low-contrast objects as well as spatial resolution was better for the full-size film-screen radiographs than for both the digital monitor images and the 100 mm photofluorograms. The image-intensifier system has a potential for considerable dose savings in relation to the conventional technique provided that fluoroscopy is excluded in the positioning of the patients.
Department of Radiation Physics, Sahlgrenska Sjukhuset, University of Gothenburg, Sweden.
L G
LG
Månsson
S
S
Kheddache
D
D
Schlossman
J
J
Börjesson
E
E
Håkansson
S
S
Mattsson
U
U
Tylén
D004735:Energy Transfer; D005189:False Positive Reactions; D012372:ROC Curve; D011856:Radiographic Image Enhancement / Q000295:instrumentation*; D013902:Radiography, Thoracic