Abstract: Objective  To explore the application value of  targeted scan combined with multiple plane reconstruction(MPR) in  diagnosis of ground glass nodules (<1 cm) in the lung.Methods  A total of 71 groundglass nodules of lung from 62 patients with conventional CT scanning  and targeted scan simultaneously in our hospital were selected. The analysis of nodules with MPR and volume rendering (VR) was performed. The morphological features of the nodules was evaluated by doubleblind method. Results  The images obtained by targeted scans were superior significantly to that of conventional scans in showing the density,  margin  and  lobulation sign of the ground glass nodules. There was statistical significance in the difference between the  clearness of the images of air bronchial signs and vascular bundle signs obtained by targeted scan combined with MPR and that obtained byconventional scans. Compared with the conventional scans, the targeted scan can enhance diagnostic confidence (P=0.000) and diagnostic accuracy (P=0.039) of physicians,increase thenumber of nodule surgeries and decrease the number of followup cases. Conclusion  The images of targeted scanning combined with MPR can clearly show the internal structure,the change of margin and the other key details of the groundglass nodules (<1 cm). For the groundglass nodules(<1  cm) which are difficult to be diagnosed by conventional CT, it is suggested to use target scan combined with MPR for further examination.

Key words: coin lesion, pulmonary; , targeted scanning, tomography, Xray computed