Congenital Anomalies of the Tracheobronchial Tree, Lung, and Mediastinum: Embryology, Radiology, and Pathology

Abstract

Congenital anomalies of the chest are an important cause of morbidity in infants, children, and even adults. The evaluation of affected patients frequently requires multiple imaging modalities to diagnose the anomaly and plan surgical correction. The authors analyze and illustrate practical aspects of certain common and uncommon congenital anomalies affecting the tracheobronchial tree, lung, and mediastinum, with emphasis on radiologic manifestations. Other thoracic anomalies such as rib anomalies and vascular rings are discussed when they are associated with anomalies of the tracheobronchial tree. The usefulness of the various imaging modalities in the diagnosis and treatment of these conditions is also evaluated. Specific topics addressed include tracheal conditions such as tracheal stenosis, tracheomalacia, tracheal bronchus, tracheal atresia, and bronchogenic cyst; anomalies of the lung such as lung underdevelopment (agenesis and hypoplasia), scimitar syndrome, congenital cystic adenomatoid malformation, congenital lobar emphysema, and pulmonary sequestration; esophageal anomalies such as esophageal atresia, tracheoesophageal fistula, and esophageal duplications; and vascular rings. The embryologic and pathologic basis of the radiologic findings are discussed in appropriate cases. Differential diagnoses, as well as pitfalls and diagnostic difficulties, are included.

Not all right-sided hearts are the same—the importance of identifying the correct diagnosis

“…The Scimitar syndrome is clearly differentiated from other forms of CPVS or PAPVR by this characteristic "Scimitar" shaped vein which is not present when it drains to other areas such as the superior vena cava (SVC). Associated anomalies include hypoplasia and abnormal lobation of the right lung, pulmonary sequestration, right pulmonary artery hypoplasia, heart dextroposition, anomalous systemic right lower lung arterial supply, atrial septal defect, and right diaphragmatic hernia (9).…”

Modern imaging of the tracheo-bronchial tree

“…It is usually detected incidentally and may not have much clinical implication. However, this anomaly may cause hypoxemia and prolonged atelectasis with intubation or during anesthesia due to inadvertent closure of the bronchial opening by the endotracheal tube [15][16][17][18][19][20] . Fur- thermore, bronchus suis is associated with other congenital anomalies, particularly trisomy 21 [21] .…”

“…It is often seen in association with other congenital anomalies, of which the VACTERL is most commonly known [15,25] . VACTERL is a well-known congenital malformation syndrome that includes vertebral, anal, cardiac, tracheoesophageal, renal, and limb anomalies.…”

“…VACTERL is a well-known congenital malformation syndrome that includes vertebral, anal, cardiac, tracheoesophageal, renal, and limb anomalies. Esophageal atresia is most commonly proximally positioned with a distal trachea-esophageal fistula (80%-90% of cases), while 5%-8% of fistulas are H-shaped without esophageal atresia [15,26] .…”

Baffle thrombosis in an adult with remote prior scimitar vein repair mimicking massive pulmonary embolism

“…Various additional cardiopulmonary variations and associations have been described including atrial (ASD) and ventricular (VSD) septal defects, pulmonary artery (PA) hypoplasia, diaphragmatic hernias, abnormal bronchopulmonary anatomy and sequestrations, vertebral and genitourinary abnormalities. 1,2 The radiographic appearances of scimitar syndrome are well known and its accompanying asymmetric perfusion on conventional angiography is documented 3 , however the associated appearance of abnormal pulmonary arterial blood flow on computed tomography pulmonary angiography (CTPA) has not previously been described. We report a case of post-operative scimitar repair and asymmetric pulmonary arterial perfusion with delayed right pulmonary blood flow, repeatedly misinterpreted as massive pulmonary embolus (PE).…”