ABSTRACT
[Abstract ] Objective To compare the accuracy between regular computed tomography colonography (CTC)and dual-energy CTC in lesion detection.Methods Twenty-eight patients with clinical suspicious space occupying lesions of the colon were selected.All patients were underwent dual-energy mode contrast-enhanced CT scan and the data were reconstructed with colonography and dual-energy iodine maps methods.The diameter,enhanced computed tomography (CT)value and iodine value were measured.The results of colonoscopy and pathology were taken as gold standard.The sensitivity, specificity,accuracy,positive predictive value and negative predictive value of regular CTC and dual-energy CTC were compared.Variance analysis was performed for measurement data comparison among groups and chi-square test was used for count data analysis.Results Among 28 patients,colorectal lesions were detected in 24 cases by regular CTC,of which four cases were false-positive and one case was false-negative confirmed by colonoscopy and pathology.Colorectal lesions were detected in 20 cases by dual-energy CTC,of which no false-positive and one case was false negative confirmed by colonoscopy and pathology.The contrast enhanced CT value of polyps,adenoma,adenocarcinoma and stool was (38.54± 6.82),(49.16±7.31 ),(52.61 ±5 .93 )and (34.00±1 .41 )Hu,respectively.The enhanced value of adenoma and adenocarcinoma was significantly higher than that of polyps and stool,the differences were statistically significant among groups (F = 10.760,P = 0.001 ).There was no significant difference between polyps and stool (t=1 .44,P =0.188).The sensitivity of regular CTC and dual-energy CTC in lesion detection was 95 .6% (95 %cofidence interval(CI ):77.9%-99.2%)and 95 .6% (95 %CI :77.9%-99.2%),respectively.The specificity was 42.8% (95 %CI :15 .4%-93.5 %)and 100.0% (95 %CI :47.9%-100.0%).Conclusion Compared with traditional CTC,dual-energy CTC would distinguish lesions from stool,help differentiate between benign and malignant tumors and further increase the accuracy of CTC diagnosis.