Abstract: Objective To explore the application of flash spiral acquisition by dual-source CT in the diagnosis of congenital heart disease complicated with cardiovascular airway constriction. Methods Children suspected with cardiovascular airway compression underwent flash spiral acquisition by dual-source CT during Jan. 2013 and Dec. 2015, and 99 山 东 大 学 学 报 (医 学 版)55卷11期 -李媛媛,等.双源CT Flash扫描在心血管源性气道狭窄患儿诊断中的临床应用 \=-children were finally included in this study, including 40 males and 59 females. The mean age was 22 months and mean body weight was(10±7.7)kg. The dose length product(DLP)was recorded to calculate effective dose(ED). Images were analyzed by two experienced radiologists using a 5-grade scoring system subjectively with post-processing technique. The diagnostic criteria were adopted to determine airway constriction. Multiple planar reformation(MPR)and volume rendering(VR)were used to show the anatomic structures around the narrow segment, and to define the responsible anomalies and location of the airway constriction. The characteristics of pulmonary lesions were observed in lung window and minimum intensity projection(MinIP). Results The average DLP was(7.32±6.19)mGy·cm, and average ED was(0.39±0.20)mSv. All images were diagnosable. The two radiologists made good agreement(K=0.754, P<0.05). With different age groups, the younger the patients, the higher proportion of cardiovascular airway constriction and pulmonary anomalies(Z=-3.83, P<0.001). Of all 99 children, a total of 104 constrictions were diagnosed as tracheobronchial compression caused by vascular abnormalities, including pulmonary arterial hypertension in 38 cases(36.5%), coarctation of aorta in 32 cases(30.8%), right-sided aortic arch in 14 cases(13.5%), innominate artery tracheal compression in 12 cases(11.5%), pulmonary artery sling in 6 cases(5.8%), double aortic arch in 1 case(1.0%)and left atrial enlargement in 1 case(1.0%). Secondary pulmonary lesions were also detected, including ground glass opacity in 36 cases, consolidation in 19 cases, emphysema in 66 cases and post-obstructive pulmonary atelectasis in 7 cases. The difference between the different types of primary heart diseases and the locations of the airway constriction was statistically significant(P<0.001). Airway constrictions caused by congenital heart disease were most likely to occur on the left main bronchus. Conclusion Flash spiral acquisition by dual-source CT can diagnose congenital heart disease with airway compression simultaneously, and provide information for clinical diagnosis and treatment.

Key words: Dual-source CT, Congenital heart disease, Radiation dosage, Airway constriction, Flash scan