Digital radiography versus conventional radiography in chest imaging: Diagnostic performance of a large-area silicon flat-panel detector in a clinical CT-controlled study

OBJECTIVE. The objective of this study was to compare the diagnostic perfor mance of a digital large-area silicon flat-panel detector with that of a co nventional screen-film system in clinical chest imaging using abnormal find ings documented by CT as the reference standard. SUBJECTS AND METHODS. Eighty patients (46 men and 34 women; age range, (91 years; mean age, 63 years) who underwent CT of the chest were examined with the new digital radiography system, which is based on a 43 x 43 cm silicon flat-panel detector, and with a conventional screen-film system, which is used routinely in clinical practice. Posteroanterior and lateral radiograph s were obtained. Four radiologists analyzed the digital and conventional im ages separately for chest abnormalities and rated the images using a five-l evel scale of confidence; CT was used as the reference standard. Diagnostic value was assessed using receiver operating characteristic curves for each abnormality. RESULTS. No significant differences were found between the area under the r eceiver operating characteristic curve of the digital and that of the conve ntional radiography method for almost all investigated criteria. The only e xception was mediastinal abnormalities, for which the digital method provid ed better results than the conventional method (p < 0.05). CONCLUSION. The diagnostic performance of the new large-area silicon flat-p anel detector is equivalent or superior to that of the conventional screen- film system for clinical chest imaging and can replace conventional radiogr aphy systems. This new technology offers transmission and storage possibili ties inherent to digital radiology that would facilitate daily practice and reduce the initial high costs in the long-term.