Objective: To explore the value of dual-source CT spectrum curve and iodine measurement in the early diagnosis of gastric cancer.
Methods: Imaging materials of 21 cases with early gastric cancer confirmed by gastroscope and pathology, and 38 cases with normal stomach in our department from November 2011 to June 2013 were retrospectively analyzed. All the cases underwent dual-energy scanning with SOMATOM Definition Flash CT. The iodine concentration of the lesion in arterial phase and venous phase was measured respectively. The iodine concentration of small curvature side and aorta of same level was also measured for the cases with normal stomach. Normalized iodine concentration (NIC) difference was studied between early gastric cancer lesions and normal gastric wall. Spectrum curve characteristics of gastric cancer lesions and normal gastric lesser curvature were analyzed.
Results: There were significant differences in NIC between early gastric cancer lesions and normal gastric wall (arterial phase, 0.21 vs. 0.09, P=0.000; venous phase, 0.72 vs. 0.26, P=0.000). Spectrum curves of normal gastric wall and early gastric cancer, both in arterial and venous phase, showed descending tendency. Spectrum curve of early gastric cancer located above that of normal gastric wall, and was more steep. Difference between these two curves became greater during 40 to 70 keV, and became smaller during 80 to 140 keV.
Conclusion: NIC and spectrum curve tendency are helpful to identify the early gastric cancer and the normal gastric wall through the dual-energy model scan.