Digital Chest Radiography with a Large Image Intensifier

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.

[1]  C. Metz.  ROC Methodology in Radiologic Imaging , 1986, Investigative radiology.

[2]  J. Persliden,et al.  Energy imparted to the patient in diagnostic radiology: calculation of conversion factors for determining the energy imparted from measurements of the air collision kerma integrated over beam area. , 1984, Physics in medicine and biology.

[3]  P M Lams,et al.  Spatial resolution requirements for digital chest radiographs: an ROC study of observer performance in selected cases. , 1986, Radiology.

[4]  S. Soimakallio,et al.  Large-Screen Image Intensifier Photofluorography Compared with Full-Size Screen-Film Technique in Chest Radiography , 1985, Acta radiologica: diagnosis.

[5]  K. Doi,et al.  Digital radiography of subtle pulmonary abnormalities: an ROC study of the effect of pixel size on observer performance. , 1986, Radiology.

[6]  F A DiBianca,et al.  The effect of varying spatial resolution on the detectability of diffuse pulmonary nodules. Assessment with digitized conventional radiographs. , 1981, Radiology.

[7]  John F. Hamilton,et al.  A Free Response Approach To The Measurement And Characterization Of Radiographic Observer Performance , 1977, Other Conferences.

[8]  C. Metz.  Basic principles of ROC analysis. , 1978, Seminars in nuclear medicine.

[9]  D. M. Green,et al.  Signal detection theory and psychophysics , 1966 .

[10]  John A. Swets,et al.  Evaluation of diagnostic systems : methods from signal detection theory , 1982 .

[11]  L. Strauss,et al.  [1 year's experience with a 57-cm image intensifier in a universal roentgen work station]. , 1985, RöFo. Fortschritte auf dem Gebiet der Röntgenstrahlen und der bildgebenden Verfahren (Print).

[12]  P. Peters,et al.  [First clinical experiences with a new large frame intensifier in thoracic diagnosis]. , 1982, RöFo. Fortschritte auf dem Gebiet der Röntgenstrahlen und der bildgebenden Verfahren (Print).

[13]  L B Lusted,et al.  Radiographic applications of receiver operating characteristic (ROC) curves. , 1974, Radiology.

[14]  R. G. Fraser,et al.  Digital and conventional chest imaging: a modified ROC study of observer performance using simulated nodules. , 1986, Radiology.

[15]  T. R. Fewell,et al.  Beam quality independent attenuation phantom for estimating patient exposure from x-ray automatic exposure controlled chest examinations. , 1984, Medical physics.