No abstract

No abstract

When both critical findings are present, the degree of small-bowel obstruction is likely high-grade or complete. When both signs are absent, small-bowel obstruction is likely low-grade or nonexistent. Upright abdominal radiographs are important in the examination of patients with suspected small-bowel obstruction and may contribute to the imaging triage of these patients.

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.

No abstract