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Vascular ring due to double aortic arch: a rare cause of dysphagia
European Journal of Radiology Extra 52 (2004) 21–24
Vascular ring due to double aortic arch: a rare cause of dysphagia Rita Baraldi, Simone Sala∗ , Stefano Bighi, Paolo Mannella Department of Radiology, Arcispedale S. Anna, Corso Giovecca 203, 44100 Ferrara, Italy Received 20 January 2004; received in revised form 28 May 2004; accepted 3 June 2004
Abstract A case of mechanical dysphagia caused by a vascular ring due to double aortic arch is reported. Esophageal stenosis and vascular ring were clearly demonstrated by contrast-enhanced spiral computerized tomography. We emphasize the role of three-dimensional reconstructions with volume rendering in the evaluation of this rare condition. © 2004 Elsevier Ireland Ltd. All rights reserved. Keywords: Aorta abnormalities; Esophageal diseases; Computed tomography
1. Introduction Mechanical dysphagia is a common disease caused by intraluminal, parietal or extrinsic esophageal lesions. Peptical stenosis, esophageal carcinoma and lower esophageal ring are the most common causes of mechanical dysphagia [1]. We report a case of extrinsic mechanical esophageal dysphagia caused by a rare congenital aortic disease, double aortic arch. Thoracic computed tomography (CT) with three-dimensional (3D) reconstructions allowed an accurate diagnosis, and clearly showed extramural compression of the esophagus due to complete vascular ring, avoiding the need for more invasive examinations such as aortography [2].
2. Case report A 36-year-old man presented a 1-year history of hiccup and progressive dysphagia towards solid food. Fiber-optic endoscopy revealed the absence of mucosal lesion, but highlighted a stenosis of the proximal thoracic tract of the esophagus. Barium esophagography showed an extrinsic stenosis of the esophagus in correspondence with the aortic arch, accompanied by dilation of the proximal tract (Fig. 1). A double impression was noted on the esophagus: the anterior indentation was due to the left arch, while the posterior im∗
Corresponding author. Tel.: +39-0532-212146. E-mail address: [email protected] (S. Sala).
pression was caused by the right arch. Chest radiography showed only a poor visibility of the aortic arch (Fig. 2). Contrast-enhanced thoracic CT with 3D reconstruction was diagnostic in defining the cause of esophageal stenosis, showing the presence of a complete vascular ring due to double aortic arch with tracheal and esophageal compression (Fig. 3). CT scan showed also the “four vessel” sign caused by four separate bracheocephalic vessels (instead of the usual three) in the superior mediastinum grouped around the trachea, clearly described by 3D reconstruction with volume rendering (Fig. 4). Although indicated, the patient refused any form of surgical correction and a follow-up program was started.
3. Discussion Extrinsic mechanical dysphagia is usually caused by mediastinal masses such as enlarged lymph nodes, paraesophageal neoplasms, ectopic thyroid tissue or vascular abnormalities; among such abnormalities, aneurysmal aortic dilation and aberrant right and left subclavian arteries are the most common causes, while vascular rings are less frequent [1]. Since Gross’ original description [3], the phrase “vascular ring” has been used to refer to a collection of congenital vascular anomalies that encircle and compress the esophagus and trachea. In his original report Gross described the two classic vascular rings: right aortic arch with left ligamentum, and divided aortic arch (now called double aortic arch).
1571-4675/$ – see front matter © 2004 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.ejrex.2004.06.001
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R. Baraldi et al. / European Journal of Radiology Extra 52 (2004) 21–24
Fig. 1. Barium esophagography. An extrinsic stenosis of the esophagus with anterior and posterior indentation due to double aortic arch may be observed. Note the initial dilation of the esophageal tract proximal to the stenosis.
Fig. 2. Chest X-ray examination reveals only a poor visibility of aortic arch. No abnormalities of pulmonary vessels or cardiac morphology are observed.
Fig. 3. Contrast-enhanced spiral CT of the chest. At a cranial level (a) the “four vessel” sign due to four separate bracheocephalic vessels (instead of the usual three) may be observed. Note also the marked dilation of air-filled esophagus. At a caudal level (b), the right aortic arch passes posteriorly with respect to the trachea and esophagus. A more caudal (c) scan shows the left aortic arch joining the right arch posteriorly. Note the limited space available for trachea and esophagus due to vascular ring. Caudally (d), a single descending thoracic aorta may be observed.
R. Baraldi et al. / European Journal of Radiology Extra 52 (2004) 21–24
Fig. 4. 3D volume rendering CT reconstruction clearly shows the double aortic arch and highlights the four separate bracheocephalic vessels arising from the vascular ring.
Although innominate artery compression syndrome and pulmonary artery sling are not complete anatomic “rings”, they are classified alongside the classic vascular rings because of their similarities in patient presentation, diagnosis and surgical therapy. Vascular rings may be explained by abnormal regression or persistence of different components of the embryonic aortic arch system [4]. Double aortic arches have been classified in two types, depending on the patency of the arches. The most frequent form is a functional double aortic arch, where the left common carotid and subclavian arteries arise from the left arch as in the case we have observed. Both arches join posteriorly to form one descending aorta, which may be midline or, more usually, left sided. The two arches may be of equal size, although generally the right one (posterior) is larger and situated higher up than the left arch, as in the case here described. The left (anterior) arch is dominant in 20% of patients, and the arches are of equal size in 5% of patients. A portion of the smaller arch is atresic in one-third of patients [5]. While uncommon, the double aortic arch is still the most common cause of vascular rings, and is generally an isolated anomaly not associated with an increased incidence of congenital heart disease. Infants with a double aortic arch typically present clinical symptoms quite early in life, mainly the classic
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“barky” cough and nearly persistent stridor. Other symptoms include asthma, recurrent pneumonia, and cyanotic spells. Esophageal symptoms include emesis, choking or dysphagia, and are more common in older infants and children. Occasionally, patients may reach puberty or even adulthood before developing persistent or progressive complaints of dysphagia or respiratory symptoms [6], as in the case here described. Vascular rings are rare in the overall spectrum of diseases causing respiratory symptoms in children, and their diagnosis requires a heightened index of suspicion. Chest radiography may usually establish the location of the aortic arch: in our case, a poor visibility of aortic arch was noted. The barium esophagram is the single most important and reliable technique for diagnosing of a vascular ring. It is also relatively inexpensive in the current era of heightened cost awareness. Conventional CT and helical CT angiography are useful in that they identify both the vascular structures and extramural abnormalities secondarily affecting the esophagus. Although magnetic resonance (MR) is the best single imaging study for the diagnosis and characterization of vascular ring, it requires multiple imaging planes which are time-consuming to perform. A single volume gadolinium-enhanced 3D MR angiography acquisition offers higher spatial resolution, higher signal-to-noise, faster acquisition times, and provides high-quality, surgically precise multiplanar informations. However, respiratory-induced blurring without breath holding can result in significant degradation of image quality with this technique [2]. CT advantages over MR imaging include rapid scanning times, which allows for examination of critically ill children without the constraints of a close-bore magnet, as well as better evaluation of the relationships of aberrant vessels with the airways and esophagus [2]. Surgical division of the vascular ring is indicated for any patient with symptoms or esophageal compression. The goal of surgical management of double aortic arch is to relieve compression of the trachea and esophagus, dividing the smaller of the two arches at a site that does not compromise blood flow to the head vessels. If necessary, to minimize residual posterior compression of the trachea or esophagus, an arteriopexy may be performed by suturing the retroesophageal aortic segment to the prevertebral fascia [7]. In this case, the absence of surgical correction might induce progressive esophageal dilation. In our opinion it is important for the radiologist to bear in mind vascular ring as a possible cause of dysphagia. References [1] Braunwald E, Fauci AS, Kasper DL, Hauser SL, Longo DL, Jameson JL. Harrison’s principles of internal medicine. New York: McGraw-Hill, 2001. [2] Naidich DP, Zerhouni EA, Siegelman SS. Computed tomography and magnetic resonance of the thorax. New York: Raven, 1991.
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R. Baraldi et al. / European Journal of Radiology Extra 52 (2004) 21–24
[3] Gross RE. Surgical relief for tracheal obstruction from a vascular ring. N Engl J Med 1945;233:586–90. [4] Edwards J. Anomalies of derivatives of the aortic arch system. Med Clin North Am 1948;32:925–49. [5] Shuford WH, Sybers RG, Weems HS. The angiographic features of double aortic arches. Am J Roentgenol 1972;116:125–40.
[6] Backer CL, Ilbawi MN, Idriss FS, et al. Vascular anomalies causing tracheoesophageal compression: review of experience in children. J Thorac Cardiovasc Surg 1989;97:725–31. [7] Backer CL, Mavroudis C. Surgical approach to vascular rings. In: Karp RB, editor. Advances in cardiac surgery. St. Louis: Mosby Year Book, 1997, p. 29–64.
Vascular ring due to double aortic arch: a rare cause of dysphagia Rita Baraldi, Simone Sala∗ , Stefano Bighi, Paolo Mannella Department of Radiology, Arcispedale S. Anna, Corso Giovecca 203, 44100 Ferrara, Italy Received 20 January 2004; received in revised form 28 May 2004; accepted 3 June 2004
Abstract A case of mechanical dysphagia caused by a vascular ring due to double aortic arch is reported. Esophageal stenosis and vascular ring were clearly demonstrated by contrast-enhanced spiral computerized tomography. We emphasize the role of three-dimensional reconstructions with volume rendering in the evaluation of this rare condition. © 2004 Elsevier Ireland Ltd. All rights reserved. Keywords: Aorta abnormalities; Esophageal diseases; Computed tomography
1. Introduction Mechanical dysphagia is a common disease caused by intraluminal, parietal or extrinsic esophageal lesions. Peptical stenosis, esophageal carcinoma and lower esophageal ring are the most common causes of mechanical dysphagia [1]. We report a case of extrinsic mechanical esophageal dysphagia caused by a rare congenital aortic disease, double aortic arch. Thoracic computed tomography (CT) with three-dimensional (3D) reconstructions allowed an accurate diagnosis, and clearly showed extramural compression of the esophagus due to complete vascular ring, avoiding the need for more invasive examinations such as aortography [2].
2. Case report A 36-year-old man presented a 1-year history of hiccup and progressive dysphagia towards solid food. Fiber-optic endoscopy revealed the absence of mucosal lesion, but highlighted a stenosis of the proximal thoracic tract of the esophagus. Barium esophagography showed an extrinsic stenosis of the esophagus in correspondence with the aortic arch, accompanied by dilation of the proximal tract (Fig. 1). A double impression was noted on the esophagus: the anterior indentation was due to the left arch, while the posterior im∗
Corresponding author. Tel.: +39-0532-212146. E-mail address: [email protected] (S. Sala).
pression was caused by the right arch. Chest radiography showed only a poor visibility of the aortic arch (Fig. 2). Contrast-enhanced thoracic CT with 3D reconstruction was diagnostic in defining the cause of esophageal stenosis, showing the presence of a complete vascular ring due to double aortic arch with tracheal and esophageal compression (Fig. 3). CT scan showed also the “four vessel” sign caused by four separate bracheocephalic vessels (instead of the usual three) in the superior mediastinum grouped around the trachea, clearly described by 3D reconstruction with volume rendering (Fig. 4). Although indicated, the patient refused any form of surgical correction and a follow-up program was started.
3. Discussion Extrinsic mechanical dysphagia is usually caused by mediastinal masses such as enlarged lymph nodes, paraesophageal neoplasms, ectopic thyroid tissue or vascular abnormalities; among such abnormalities, aneurysmal aortic dilation and aberrant right and left subclavian arteries are the most common causes, while vascular rings are less frequent [1]. Since Gross’ original description [3], the phrase “vascular ring” has been used to refer to a collection of congenital vascular anomalies that encircle and compress the esophagus and trachea. In his original report Gross described the two classic vascular rings: right aortic arch with left ligamentum, and divided aortic arch (now called double aortic arch).
1571-4675/$ – see front matter © 2004 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.ejrex.2004.06.001
22
R. Baraldi et al. / European Journal of Radiology Extra 52 (2004) 21–24
Fig. 1. Barium esophagography. An extrinsic stenosis of the esophagus with anterior and posterior indentation due to double aortic arch may be observed. Note the initial dilation of the esophageal tract proximal to the stenosis.
Fig. 2. Chest X-ray examination reveals only a poor visibility of aortic arch. No abnormalities of pulmonary vessels or cardiac morphology are observed.
Fig. 3. Contrast-enhanced spiral CT of the chest. At a cranial level (a) the “four vessel” sign due to four separate bracheocephalic vessels (instead of the usual three) may be observed. Note also the marked dilation of air-filled esophagus. At a caudal level (b), the right aortic arch passes posteriorly with respect to the trachea and esophagus. A more caudal (c) scan shows the left aortic arch joining the right arch posteriorly. Note the limited space available for trachea and esophagus due to vascular ring. Caudally (d), a single descending thoracic aorta may be observed.
R. Baraldi et al. / European Journal of Radiology Extra 52 (2004) 21–24
Fig. 4. 3D volume rendering CT reconstruction clearly shows the double aortic arch and highlights the four separate bracheocephalic vessels arising from the vascular ring.
Although innominate artery compression syndrome and pulmonary artery sling are not complete anatomic “rings”, they are classified alongside the classic vascular rings because of their similarities in patient presentation, diagnosis and surgical therapy. Vascular rings may be explained by abnormal regression or persistence of different components of the embryonic aortic arch system [4]. Double aortic arches have been classified in two types, depending on the patency of the arches. The most frequent form is a functional double aortic arch, where the left common carotid and subclavian arteries arise from the left arch as in the case we have observed. Both arches join posteriorly to form one descending aorta, which may be midline or, more usually, left sided. The two arches may be of equal size, although generally the right one (posterior) is larger and situated higher up than the left arch, as in the case here described. The left (anterior) arch is dominant in 20% of patients, and the arches are of equal size in 5% of patients. A portion of the smaller arch is atresic in one-third of patients [5]. While uncommon, the double aortic arch is still the most common cause of vascular rings, and is generally an isolated anomaly not associated with an increased incidence of congenital heart disease. Infants with a double aortic arch typically present clinical symptoms quite early in life, mainly the classic
23
“barky” cough and nearly persistent stridor. Other symptoms include asthma, recurrent pneumonia, and cyanotic spells. Esophageal symptoms include emesis, choking or dysphagia, and are more common in older infants and children. Occasionally, patients may reach puberty or even adulthood before developing persistent or progressive complaints of dysphagia or respiratory symptoms [6], as in the case here described. Vascular rings are rare in the overall spectrum of diseases causing respiratory symptoms in children, and their diagnosis requires a heightened index of suspicion. Chest radiography may usually establish the location of the aortic arch: in our case, a poor visibility of aortic arch was noted. The barium esophagram is the single most important and reliable technique for diagnosing of a vascular ring. It is also relatively inexpensive in the current era of heightened cost awareness. Conventional CT and helical CT angiography are useful in that they identify both the vascular structures and extramural abnormalities secondarily affecting the esophagus. Although magnetic resonance (MR) is the best single imaging study for the diagnosis and characterization of vascular ring, it requires multiple imaging planes which are time-consuming to perform. A single volume gadolinium-enhanced 3D MR angiography acquisition offers higher spatial resolution, higher signal-to-noise, faster acquisition times, and provides high-quality, surgically precise multiplanar informations. However, respiratory-induced blurring without breath holding can result in significant degradation of image quality with this technique [2]. CT advantages over MR imaging include rapid scanning times, which allows for examination of critically ill children without the constraints of a close-bore magnet, as well as better evaluation of the relationships of aberrant vessels with the airways and esophagus [2]. Surgical division of the vascular ring is indicated for any patient with symptoms or esophageal compression. The goal of surgical management of double aortic arch is to relieve compression of the trachea and esophagus, dividing the smaller of the two arches at a site that does not compromise blood flow to the head vessels. If necessary, to minimize residual posterior compression of the trachea or esophagus, an arteriopexy may be performed by suturing the retroesophageal aortic segment to the prevertebral fascia [7]. In this case, the absence of surgical correction might induce progressive esophageal dilation. In our opinion it is important for the radiologist to bear in mind vascular ring as a possible cause of dysphagia. References [1] Braunwald E, Fauci AS, Kasper DL, Hauser SL, Longo DL, Jameson JL. Harrison’s principles of internal medicine. New York: McGraw-Hill, 2001. [2] Naidich DP, Zerhouni EA, Siegelman SS. Computed tomography and magnetic resonance of the thorax. New York: Raven, 1991.
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R. Baraldi et al. / European Journal of Radiology Extra 52 (2004) 21–24
[3] Gross RE. Surgical relief for tracheal obstruction from a vascular ring. N Engl J Med 1945;233:586–90. [4] Edwards J. Anomalies of derivatives of the aortic arch system. Med Clin North Am 1948;32:925–49. [5] Shuford WH, Sybers RG, Weems HS. The angiographic features of double aortic arches. Am J Roentgenol 1972;116:125–40.
[6] Backer CL, Ilbawi MN, Idriss FS, et al. Vascular anomalies causing tracheoesophageal compression: review of experience in children. J Thorac Cardiovasc Surg 1989;97:725–31. [7] Backer CL, Mavroudis C. Surgical approach to vascular rings. In: Karp RB, editor. Advances in cardiac surgery. St. Louis: Mosby Year Book, 1997, p. 29–64.