Retrosternal density: A sign of pulmonary hypoplasia

Abstract

An anterior increased density, that parallels the posterior border of the sternum, was noted on the lateral radiograph of two children who were at first thought to have an accessory diaphragm. After a long follow-up and further investigations, it is now felt that this sign is solely due to upper lobe hypoplasia.

Causes of congenital unilateral pulmonary hypoplasia: a study of 33 cases

“…The diagnosis of accessory diaphragm cannot be made with certainty preoperatively. It should be considered in patients with hypoplasia of the right lung, when there is an obliteration of the right cardiac border or superior mediastinum, a large pleural apical cap, and a retrosternal stripe but these findings are not specific, as they reflect only an absence of a lobe or lobes [1][2][3]. Similarly, an arterial supply of the right lower lobe from the abdominal or from the descending thoracic aorta is seen in most if not all cases of accessory diaphragm but also this finding is not specific as it may be observed also in other conditions.…”

“…A retrosternal dense stripe or a thick apical pleural cap similar to that shown in Figures 2, 5, 6 and 7, was observed in some cases. These densities are believed to represent extrapleural accumulation of areolar connective tissue replacing absent lobe(s) [1][2][3]. The vasculature of the small lung in the chest roentgenograms commonly was decreased and in the angiograms the pulmonary artery and branches were generally smaller than normal, sometimes very hypoplastic.…”

Primary Unilateral Pulmonary Hypoplasia: Neonate through Early Childhood — Case Report, Radiographic Diagnosis and Review of the Literature

“…Cases of isolated lobar defects with or without tracheobronchial abnormalities, has only been rarely reported. [8][9][10][11][12][13] With unilateral lobar pulmonary hypoplasia, gross pathology of the affected lobes shows a decrease in size and weight and, histologically, a decrease in the number of alveoli. The alveoli are often immature but otherwise demonstrate no distinct abnormalities.…”

New variation of scimitar syndrome with tracheal bronchus, upper lobe agenesis, and ventricular septal defect in a child

“…In typical SS, anomalous pulmonary drainage of part or all of the right lung into the inferior vena cava, anomalous systemic arterial supply of the right lung from either the thoracic or abdominal aorta, and hypoplasia of the right lung occur 1 . Abnormal bronchial anatomy, abnormal diaphragm, hemivertebrae, and genitourinary tract anomalies can also manifest in SS 2,3 . Generally, the symptoms of this syndrome appear 7 months after birth 4 .…”

“…1 Abnormal bronchial anatomy, abnormal diaphragm, hemivertebrae, and genitourinary tract anomalies can also manifest in SS. 2,3 Generally, the symptoms of this syndrome appear 7 months after birth. 4 According to the literature, there have been numerous cases where additional features of the typical syndrome have been reported with Scimitar variants.…”