Dysphagia lusoria and complex anomalies of the aortic arch: a rare case

Clinical History

Two months lasting dysphagia in an adult female

Imaging Findings

A 52 years old woman presented to our hospital referring a two-months lasting dysphagia. No abnormalities were evidenced at objective examination and an echographic control performed in the neck region showed no alterations of the local structures. For the diagnostic evaluation of the cause of dysphagia was therefore carried out a computed tomography of the thorax using a 64 slice MDCT (Sensation 64, Siemens, Germany). A high-resolution scan (100 mAs, 120 KV, Coll 0.6, Rec. Int.0.75, Sl. Tck. 1 mm) was performed after intravenous injection of 80 ml of nonionic iodinated contrast material. The images acquired with this protocol were subsequently transferred to two different dedicated workstations: Vitrea 3.7 Vital Images (Plymouth, USA) for post-processing algorithm. CT scan revealed a complex anomaly of the aortic arch branches: an aberrant right subclavian artery (arteria lusoria) arising from distal aortic arch, which passes through the mediastinum behind the trachea and oesophagus compressing it; was also evidenced the origin of both carotid arteries from a common trunk. The images obtained with Volume Rendering (VR) reconstruction algorithm provided a selective visualization of the anomalous vascular complex and its relationship with the adjacent structures, suggesting the connection between symptomatology and anatomic alteration.

Discussion

The right subclavian artery has an anomalous origin in less than 1 per cent of the general population. Fortunately, most of these persons do not have symptoms. However, if they undergo any neck surgery, they may be at an increased risk for damage to the right recurrent laryngeal nerve. Hunald (1735) reported an anomalous right subclavian artery for the first time. Dysphagia lusoria is described in the literature as difficulty in swallowing because of a “jest of nature”: the “jest of nature” is a birth defect encompassing any aortic root vascular anomaly that causes esophageal dysphagia. The embryologic abnormality of the aortic arch is involution of the fourth vascular arch, along with the right dorsal aorta, leaving the seventh intersegmental artery attached to the descending aorta. This persistent intersegmental artery assumes a retroesophageal position as it proceeds out of the thorax. The lusorian artery is a rare anomaly of the right subclavian artery. This artery arises from the aortic arch distal of the left subclavian artery, crossing the midline behind the esophagus. This can result in dysphagia, which appears after the age of 40 years. Mediastinal abnormality may be seen on chest x-ray. Noninvasive imagings of the chest with either computerized tomography or magnetic resonance scanning are excellent methods for evaluating the mediastinum for solid tumors or vascular anomalies that can cause extrinsic esophageal compression. Endoscopy may reveal a pulsating impression in the esophagus. Barium contrast examination of the esophagus shows a diagonal impression at level of the fourth thoracic vertebra in all patients. The association of aberrant subclavian artery with other anomalies of the epiaortic vascular trunks is extremely rare, due to the rarity of the separed anomalies by themselves. There exist only few cases in which a lusor subclavian artery is associated with a common carotid trunk. The treatment of this condition is the same as for lusor subclavian: an open surgical approach is usually required to resolve esophageal compression; during this procedure must be carefully avoided the damage of surrounding stuctures as brachial plexus or vertebral artery.

Differential Diagnosis List

Final Diagnosis

Dysphagia lusoria in association with common carotid trunk

URL:	https://www.eurorad.org/case/3974
DOI:	10.1594/EURORAD/CASE.3974
ISSN:	1563-4086