Assessment of tetralogy of Fallot–associated congenital extracardiac vascular anomalies in pediatric patients using low-dose dual-source computed tomography

BACKGROUND: To investigate the diagnostic value of dual-source computed tomography (DSCT) in the evaluation of tetralogy of Fallot (TOF)-associated extracardiac vascular abnormalities in pediatric patients compared with transthoracic echocardiography (TTE). METHODS: One hundred and twenty-three pediatric patients diagnosed with TOF were included in this retrospective study. All patients underwent DSCT and TTE preoperatively. All associated extracardiac vascular abnormalities and their percentages were recorded. The diagnostic performances of DSCT and TTE were compared based on the surgical results. The image quality of DSCT was rated, and the effective radiation dose (ED) was calculated. RESULTS: A total of 159 associated extracardiac vascular deformities were confirmed by surgery. Patent ductus arteriosus (36, 22.64%), right-sided aortic arch (29, 18.24%), and pulmonary valve stenosis (23, 14.47%) were the most common associated extracardiac vascular abnormalities. DSCT was superior to TTE in demonstrating associated extracardiac anomalies (diagnostic accuracy: 99.13% vs. 97.39%; sensitivity: 92.45% vs. 77.07%; specificity: 99.81% vs. 99.42%). The agreement on grading the image quality of DSCT was excellent (κ = 0.80), and the mean score of the image quality was 3.39 ± 0.50. The mean ED of DSCT was 0.86 ± 0.47 mSv. CONCLUSIONS: Compared to TTE, low-dose DSCT has high diagnostic accuracy in the depiction of associated extracardiac vascular anomalies in pediatric patients with TOF, and could provide more morphological details for surgeons.