Multi-modality evaluation of the abnormalities of the aortic arches in children: techniques and imaging spectrum with emphasis on MRI

Abstract

The failure of embryonic vascular arches to fuse and regress in the usual manner during the formation of the aortic arch, pulmonary arteries and ductus arteriosus can cause a wide spectrum of vascular congenital abnormalities of the aortic arch and its branches. These abnormal vascular structures may cause variable compression of the trachea and/or oesophagus with symptoms ranging from none to severe stridor, dyspnoea, dysphagia and cyanosis. Diagnosis and possible treatment of affected patients require multiple imaging modalities. In the majority of cases, the underlying malformation can be detected by chest radiography and barium oesophagography, visualizing the location of the aortic arch and the presence of anomalous compressions of the trachea and/or oesophagus. However, in most cases the exact configuration of the vascular abnormality cannot be fully defined with conventional radiology alone. MRI is fundamental for evaluation of the thoracic vessels. Not only is it non-invasive, but it can also provide large-field-of-view images in any number of planes with three-dimensional reconstruction, adding valuable information about exact vascular configuration, tracheobronchial compression and brachiocephalic vessel branching. The aim of this review is to describe the imaging findings in children affected with special emphasis on MRI.

Rings and Slings Revisited

“…If symptomatic, usually presenting from childhood to adult age with swallowing difficulty rather than respiratory distress, surgical division of the ligamentum arteriosum via thoracotomy is the usual management. 3,7 Rarely, a left aortic arch with aberrant right subclavian artery and rightsided ductus arteriosus or ligamentum arteriosum may cause a mirror image vascular ring of the right aortic arch with aberrant left subclavian artery. 16 …”

Coarctation of the aorta in adults: preoperative evaluation with MDCT angiography

“…Compared with MR angiography, MDCT angiography has the advantage of the ability to acquire high spatial resolution in a shorter acquisition time. In addition, volume rendered and multiplanar reconstructions are better for MDCT angiography data display than MRI (13). MDCT with multiplanar and three-dimensional techniques provides morphologic images of coarctation of the aorta and its relationship to the arch vessels, as well as demonstrating collateral circulatory pathways (4,5).…”

Contrast-enhanced MR angiography of thoracic vascular malformations in children

“…In patients with double aortic arch, it is mandatory to evaluate the posterior segment of the right arch. If hypoplasia or atresia is seen in the right arch it is necessary to perform a right thoracotomy instead of the left approach [19]. Three-dimensional data set with posterior coronal views obtained by MR angiography may successfully show the union of two arches into descending aorta (Fig.…”

“…Three-dimensional data set with posterior coronal views obtained by MR angiography may successfully show the union of two arches into descending aorta (Fig. 7) and laterality of the descending aorta, permitting assessment of the completeness of the ring and, if present Kommerell diverticulum [19].…”