Abnormal air-filled spaces in the lung.

Abstract

The authors reviewed the radiographic and computed tomographic (CT) appearances of abnormal air-filled spaces in the lung that develop in response to lung diseases. The major types of these lung diseases include infection, vessel-related or vascular-embolic disorders, bronchiectasis, emphysema, pulmonary fibrosis, adult respiratory distress syndrome and air-block diseases, and unusual disorders of the lung (such as Langerhans cell histiocytosis, Klippel-Trenaunay syndrome, and tracheolaryngeal papillomatosis). After studying the CT scans, conventional radiographs, and medical records of 150 patients with various abnormal air-filled spaces in their lungs and 300 lung specimens and the corresponding high-resolution CT scans, the authors concluded that mechanisms of air-space formation fall into five basic categories: (a) vascular occlusion or ischemic necrosis, (b) dilatation of the bronchi, (c) disruption of the elastic fiber network of the lung, (d) remodeling of the lung architecture and retractile fibrosis, and (e) multifactorial or unknown mechanisms.

Cystic Lung Disease: a Comparison of Cystic Size, as Seen on Expiratory and Inspiratory HRCT Scans

“…Abnormal air-filled spaces develop in response to diseases which include Langerhans cell histiocytosis, lymphaniomyomatosis, cystic bronchiectasis, honeycombing and confluent centrilobular emphysema, paraseptal emphysema and bullae. Various mechanisms of cystic formation have been proposed, including vascular occlusion or ischemic necrosis, dilatation of the bronchi, disruption of the elastic fibernetwork of the lung, remodeling of the lung architecture, refractile fibrosis, and a check-valve effect in bronchiolar stenosis (5). …”

Imagerie tomodensitométrique des lésions pulmonaires excavées

“…L'air pourrait provenir des alvéoles collaté-rales voisines situées dans le poumon sain [41], d'une communication oesophagienne, d'une communication bronchique anormale constituée lors d'une infection [42]. L'aspect radiographique des séquestrations est soit une masse solide et homogène à contours lobulés, soit une opacité alvéolaire mal systématisée ou postéro-basale unilatérale, soit des kystes [1,8] uniques ou multiples à parois fines [43]. Leur taille et leur forme sont variables.…”

Appropriate Evaluation of Large Airways Disease With Logical Imaging Sequence

“…Involvement of the trachea and lung parenchyma by this disease is rare, 5% and 1%, respectively. 5,7,12,34,35 Squamous cell papillomas are considered benign neoplasms but have approximately a 10% rate of degenerating into squamous cell carcinoma. Squamous cell papillomas (Fig.…”