MDCT Evaluation of the Prevalence of Tracheomalacia in Children With Mediastinal Aortic Vascular Anomalies

Abstract

The purpose of this study is to determine the prevalence of tracheomalacia (TM) associated with different types of mediastinal aortic vascular anomalies in symptomatic children using paired inspiratory-expiratory multidetector computed tomography (MDCT). The study group consisted of 15 consecutive symptomatic pediatric patients (12 males/3 females; mean age of 4.4 y; age range of 2 wk to 16 y) with mediastinal aortic vascular anomalies, who were referred for paired inspiratory-expiratory MDCT during a 35-month time period. Computed tomography (CT) angiography was also concurrently performed during the end-inspiration phase of the study. Two radiologists in consensus reviewed all CT images in a randomized and blinded fashion. End-inspiration and end-expiration CT images were reviewed for the presence and severity of tracheal narrowing and the type of mediastinal aortic vascular anomaly involved. TM was defined as > or =50% reduction in tracheal cross-sectional luminal area between end-inspiration and end-expiration. The presence of TM was correlated with the type of mediastinal aortic vascular anomaly and compared with the bronchoscopy results when available (n=9). Mediastinal aortic vascular anomalies included innominate artery compression (IAC) (n=6), a right aortic arch with an aberrant left subclavian artery (n=5), double aortic arch (n=3), and a left aortic arch with an aberrant right subclavian artery (n=1). Eight of 15 (53.3%) patients demonstrated TM. TM was seen in all 6 patients (100%) with IAC, 1 of 3 (33.3%) patients with double aortic arch, and 1 of 5 (20%) patients with a right aortic arch with an aberrant left subclavian artery. CT results were concordant with the results of bronchoscopy in all patients who underwent this procedure (n=9). Symptomatic pediatric patients with mediastinal aortic vascular anomalies have a relatively high prevalence of TM, especially those with IAC. Paired inspiratory-expiratory MDCT should be considered part of the routine preoperative evaluation of TM in symptomatic children with IAC and also has the potential to play a role in evaluating patients with other mediastinal aortic vascular anomalies.