Fletcher B D, Cohn R C
Department of Radiology, University Hospitals of Cleveland.
Radiology. 1989 Jan;170(1 Pt 1):103-7. doi: 10.1148/radiology.170.1.2642337.
Magnetic resonance (MR) imaging offers a noninvasive method of evaluating the mediastinum in infants with suspected compression of the trachea by the innominate artery. MR imaging was performed in 17 infants and children, aged 3-29 months, who had obstructive airway symptoms and who had undergone flexible fiberoptic tracheobronchoscopy. MR and endoscopic findings correlated in all cases but one. Of the remaining 16 patients, eight had endoscopic and MR evidence of tracheal compression at the level of the innominate artery, and eight had a normal upper thoracic trachea. In both groups, the innominate artery was situated anterior and to the left of the trachea with no difference in anatomic relationships. Measurements of the anteroposterior and transverse dimensions of the upper part of the mediastinum and the thymus failed to disclose significant differences between the two groups. Follow-up examinations of three patients showed decreasing tracheal compression without changes in tracheal-arterial relationships. This investigation disclosed no evidence of excessive mediastinal crowding. The findings support previous angiographic observations indicating that anterior tracheal compression is not due to an anomalous position of the innominate artery. Symptoms of tracheal compression may result from an intrinsic deficiency of the tracheal cartilage rather than an anatomic abnormality of the mediastinum or its vasculature.
磁共振（MR）成像为评估疑似无名动脉压迫气管的婴儿纵隔提供了一种非侵入性方法。对17名年龄在3至29个月、有气道梗阻症状且已接受可弯曲纤维支气管镜检查的婴儿和儿童进行了MR成像检查。除1例病例外，MR和内镜检查结果在所有病例中均相关。在其余16例患者中，8例在内镜和MR检查中显示在无名动脉水平存在气管压迫，8例上胸段气管正常。在两组中，无名动脉均位于气管前方和左侧，解剖关系无差异。对纵隔上部和胸腺的前后径及横径测量未发现两组之间存在显著差异。对3例患者的随访检查显示气管压迫减轻，气管与动脉的关系无变化。本研究未发现纵隔过度拥挤的证据。这些发现支持了先前的血管造影观察结果，即气管前方压迫并非由无名动脉位置异常所致。气管压迫症状可能源于气管软骨的内在缺陷，而非纵隔或其血管系统的解剖异常。
