A Clinical Study On Low-dose Computed Tomography Virtual Colonoscopy For Early Screening Colorectal Masses By Using A Third-generation Dual-source Ct

Objective To evaluate the accuracy of third-generation dual-source low radiation dose CT virtual colonoscopy(CTVC)in the diagnosis of colorectal lesions,especially colorectal space-occupying lesions,and to explore its clinical value and the feasibility of its large-scale application in screening colorectal space occupying diseases widely in population.Methods Prospectively enrolled 1016 high-risk patients with colon lesions.Of which 330 patients received the Third generation Dual-source low radiation dose CT virtual colonoscopy after being selected by inclusion and exclusion criteria.Finally 316 patients(including 121 males and 195 females,aged 27-78 years,with an average age of(50.8±9.1)years and 245 patients aged 45 years and above,with an average BMI of(23.8±3.2)kg/m2.)underwent surgical painless colonoscopy/surgery(pathology)at the same time.Painless electronic colonoscopy and pathological results were taken as the gold standard to evaluate the sensitivity,specificity,positive predictive value,negative predictive value and accuracy of the Third generation Dual-source low radiation dose CT virtual colonoscopy(CTVC)in diagnosing colorectal lesions,especially colorectal space occupying lesions,calculate the Effective Dose(ED)for examination.explore the correlation between age,sex,BMI,special medical history and colorectal space occupying diseases.Results(1)The Third generation Dual-source low radiation dose CT virtual colonoscopy diagnosed intestinal diverticulum in 3 cases,ileocecal valve lesion in 2 cases,lipoma in 1 case,varicose vein in 1 case,colorectal space occupying lesion in 119 cases(polyp in 108 cases,adenocarcinoma in 11 cases).(2)Accuracy evaluation: The sensitivity,specificity and accuracy of the third generation dual-source low radiation dose CT virtual colonoscopy indiagnosing colorectal space occupying lesions were 97.4%,97.5% and 97.5%,respectively.The AUC of the area under ROC curve was 0.975(95% CI 0.954-0.995),with high diagnostic efficiency.The results of diagnosis of colorectal cancer(CRC)and surgery(pathology)are completely consistent(P<0.05),and the diagnosis rate of colorectal cancer is 100%.(3)The subjects received effective radiation metering(ED)of(0.49 ~ 2.30)mSv,with an average of(1.31±0.30)mSv.(4)Age,female sex,Cystic lesions(including gallbladder diseases/after cholecystectomy/ cholelithiasis accidental discovery of gallstones by colonoscopy,etc.)are high risk factors for colorectal space occupying diseases.(5)Discovery of diseases outside the colon: hysteromyoma in 5 patients,bladder diverticulum in 1 patient,hepatic cyst in 12 patients,renal calculus in 3 patients,renal cyst in 9 patients,prostatic calcification in 6patients and prolapse of lumbar intervertebral disc in 6 patients.Conclusion The Third generation Dual-source CT virtual colonoscopy showed low radiation dose;Compared with electronic colonoscopy and pathology,the sensitivity,specificity and accuracy of colorectal space occupying lesions were 97.4%,97.5% and 97.5%respectively.Age,female and gallbladder lesions are the risk factors for colorectal space occupying lesions.It has important value in guiding the discovery of surgical operation and parenteral diseases.It can be used as a noninvasive,simple and effective method for screening colorectal space occupying disease in high-risk population,and it is worthy of further promotion in clinical practice.