Horseshoe lung associated with left lung hypoplasia and single left pulmonary vein; A rare combination

摘要

Horseshoe lung (HL) is a rare bronchovascular anomaly in which the posterobasal segments of the right and left lung are fused with a narrow isthmus of pulmonary parenchyma in a common pleural space behind the heart and anterior to the aorta and oesophagus. HL is mostly associated with unilateral lung hypoplasia (most frequently the right lung) in conjunction with the Scimitar syndrome and is also associated with cardiovascular anomalies, such as atrial septal defects, ventricular septal defects, tetralogy of Fallot, and hypoplastic left ventricule.HL with left lung hypoplasia is extremely rare, with only a few cases reported in the literature. To the authors' knowledge, this is the first case of HL associated with left lung hypoplasia and a single left pulmonary vein as depicted using multidetector computed tomography (MDCT) in the literature. These complex bronchovascular anomalies require angiography, bronchoscopy, echocardiography, and also CT for correct diagnosis. With development of MDCT, a non-invasive imaging technique, it is possible to visualize vascular, bronchial, and parenchymal structures during a single imaging session via multiplanar two (2D) and three-dimensional (3D) images.