Unsharp masking of low-dosed digital luminescence radiographs: results of a receiver operating characteristics...

The extent to which the diagnostic performance of low-dosed storage phosphors can be improved by suitable image postprocessing was investigated. Storage phosphor radiographs and conventional 200- and 400-speed screen-film combinations of an anthropomorphic chest phantom with simulated nodules and linear structures were compared. The detection of test bodies was determined in a ROC analysis based on 16200 individual observations. The two analog screen-film systems did not differ significantly. As far as the storage phosphor radiographs are concerned, a higher diagnostic performance was achieved with a large filter kernel (S 40) whereas small filter kernels and edge-enhanced imaging modes reduced the detection of detail. The image quality of low-dosed storage phosphors is thus similar to high-amplification screen-film combinations if large filter kernels are used in postprocessing of the image.