Purpose: To compare the clinical usefulness of the single-exposure dual-energy subtraction method with an iterative noise-reduction algorithm.
Materials and methods: Fourteen radiologists read three sets of images from 44 patients: original computed radiographic images only, original computed radiographic images plus conventional bone-subtracted images, and original computed radiographic images plus iterative noise-reduced bone-subtracted images. Twenty-two patients had one or more (maximum, five) pulmonary nodules; 22 had no pulmonary nodules. Observer performance was evaluated by means of calculation of the average area under the alternative free-response receiver operating characteristic curves (A1).
Results: Compared with the original computed radiographic image only, detection of nodules was significantly better with both the original computed radiographic image plus iterative bone-subtracted image (A1 = 0.72 +/- 0.02 and 0.66 +/- 0.02, respectively; P = .01) and the original computed radiographic image plus conventional bone-subtracted image (A1 = 0.66 +/- 0.02 and 0.61 +/- 0.01, respectively; P = .03).
Conclusion: The iterative noise-reduction algorithm is superior to conventional methods in detection of pulmonary nodules.