Digital thoracic radiology: techniques, image processing, limits.

In a first part, the different techniques of digital thoracic radiography a re described. Since computed radiography with phosphore plates are the most commercialized it is more emphasized. But the other detectors are also des cribed, as the drum coated with selenium and the direct digital radiography with selenium detectors. The other detectors are also studied in particula r indirect flat panels detectors and the system with four high resolution C CD cameras. In a second step the most important image processing are discussed: the gra dation curves, the unsharp mask processing, the system MUSICA, the dynamic range compression or reduction, the soustraction with dual energy. In the last part the advantages and the drawbacks of computed thoracic radi ography are emphasized, The most important are the almost constant good qua lity of the pictures and the possibilities of image processing.