A Preliminary Study Of Dual-energy Virtual Non-contrast CT Of Dual Source CT In The Diagnosis Of Lung Cancer

Objective: To investigate the value of dual-energy virtual non-contrast (VNC) of dualsource computed tomography (CT) in the diagnosis of lung cancer.Methods:50cases of suspected patients with lung cancer including34cases lung cancerproved by pathology were performed conventional plain scan and dual energy enhancedscan. Conventional plain scan images and VNC images of50cases of patients wereobserved. Measuring mean CT values of descending aorta and the left atrium and themuscles and calculating signal to noise ratio (SNR), and the paired t test was used toanalyze difference by two sets of data. The image quality was evaluated by conventionalplain scan images as a reference image. The CT values of lung cancer on enhancedweighted average and virtual non-contrast images were compared by using Liver VNCprocessing unit. In the CT value difference of tumor≥20HU diagnosing lung cancer as astandard, the diagnostic accuracy was compared for investigating34cases lung cancerproved by pathology. The patient radiation dose was evaluated between conventional plainscan and virtual dual-energy scan.Results: In50cases of patients, mean CT values of descending aorta in conventionalplain scan and VNC scan were45.13±3.90,47.01±3.13,(P＜0.05), the difference wasstatistically significant. mean CT values of the left atrium in conventional plain scan andVNC scan were44.99±4.65,46.08±3.56, mean CT values of the muscles in conventionalplain scan and VNC scan were46.18±2.01,46.44±2.33,(P＞0.05), their difference were notstatistically significant(all P＞0.05). SNR of descending aorta and the left atrium and themuscles in conventional plain scan were15.02±1.00,13.71±1.06,19.93±1.00, three sets ofdata pairwise compared all P＞0.05, the difference was statistically significant. In50casesof conventional plain scan and VNC scan average scores of image quality were4.65±0.48,4.60±0.50,(P＞0.05), their difference were not statistically significant. After the finalpathology confirmed34cases of lung cancer, the tumors CT increase of value were38.69±18.3HU. when the increase of value≥20HU diagnosing lung cancer, the accuracy was94.1%(32/34). Comparison of their difference of the patient radiation dose withconventional plain scan and dual-energy scan were statistically significant(P＜0.05).VNC’s CTDIvol、DLP、ED were slightly higher than conventional plain scan, but usingVNC technology saved a conventional plain scan’s radiation dose, and reduced2.29mSveffective dose.Conclusion: Dual-energy VNC technology of dual source CT in the chest caneffectively reduce the patients received radiation doses, and ensuring image quality to meetthe requirements of the clinical diagnosis, the technology has a higher clinical value in thediagnosis lung cancer.