Is targeted reconstruction necessary for evaluating contrast-enhanced chest computed tomography using a liquid crystal display monitor?

Purpose. The aim of this study was to examine whether 20-cm field-of-view (FOV) targeted reconstruction (TR) on contrast-enhanced (CE) chest computed tomography (CT) might improve the diagnostic value compared with simple zooming (SZ) from whole-thorax FOV images using a 2 million (2M)-pixel liquid crystal display (LCD) monitor. Materials and methods. We prospectively evaluated 44 patients. SZ images were magnified from a FOV of 26-34 cm (mean 29.7 cm). Parameters were 512 × 512 matrix and 3 mm thickness and interval. Images were reconstructed using a soft-tissue kernel. Three radiologists evaluated contour, spiculation, notch, pleural tag, invasion, and internal characteristics of the lesions using 5-scale scores. We also performed a phantom study to evaluate the spatial resolution of images. Results. The diagnostic value of the TR images was similar to that of the SZ images, with the findings identified in 88%-100% of the cases. Artifacts from highdensity structures deteriorated the image quality in six (14%), and the SZ images were judged to be preferable in five of them. In the phantom study, there was little difference in spatial resolution between the two images. Conclusion. The SZ images from whole-thorax FOV on CE chest CT were similar in quality to TR images using a 2M-pixel LCD monitor.