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A bronchus is a passage or airway in the lower respiratory tract that conducts air into the lungs. The first or primary bronchi to branch from the trachea at the carina are the right main bronchus and the left main bronchus. These are the widest bronchi, and enter the right lung, and the left lung at each hilum. The main bronchi branch into narrower secondary bronchi or lobar bronchi, and these branch into narrower tertiary bronchi or segmental bronchi. Further divisions of the segmental bronchi are known as 4th order, 5th order, and 6th order segmental bronchi, or grouped together as subsegmental bronchi. The bronchi, when too narrow to be supported by cartilage, are known as bronchioles. No gas exchange takes place in the bronchi.
The azygos vein is a vein running up the right side of the thoracic vertebral column draining itself towards the superior vena cava. It connects the systems of superior vena cava and inferior vena cava and can provide an alternative path for blood to the right atrium when either of the venae cavae is blocked.
In medical or research imaging, an incidental imaging finding is an unanticipated finding which is not related to the original diagnostic inquiry. As with other types of incidental medical findings, they may represent a diagnostic, ethical, and philosophical dilemma because their significance is unclear. While some coincidental findings may lead to beneficial diagnoses, others may lead to overdiagnosis that results in unnecessary testing and treatment, sometimes called the "cascade effect".
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Scimitar syndrome, or congenital pulmonary venolobar syndrome, is a rare congenital heart defect characterized by anomalous venous return from the right lung. This anomalous pulmonary venous return can be either partial (PAPVR) or total (TAPVR). The syndrome associated with PAPVR is more commonly known as Scimitar syndrome after the curvilinear pattern created on a chest radiograph by the pulmonary veins that drain to the inferior vena cava. This radiographic density often has the shape of a scimitar, a type of curved sword. The syndrome was first described by Catherine Neill in 1960.
A bronchopulmonary segment is a portion of lung supplied by a specific segmental bronchus and its vessels. These arteries branch from the pulmonary and bronchial arteries, and run together through the center of the segment. Veins and lymphatic vessels drain along the edges of the segment. The segments are separated from each other by layers of connective tissue that forms them into discrete anatomical and functional units. This separation means that a bronchopulmonary segment can be surgically removed without affecting the function of the others.
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In radiology, the Golden S sign, also known as the S sign of Golden, is a radiologic sign seen on chest X-ray that suggests a central lung mass or a lung collapse. It was first described by, and subsequently named after, Dr Ross Golden (1889–1975) in 1925 in association with bronchial carcinoma, but it is also seen in metastatic cancer, enlarged lymph nodes, and collapse of the right upper lobe of the lung.
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Lung surgery is a type of thoracic surgery involving the repair or removal of lung tissue, and can be used to treat a variety of conditions ranging from lung cancer to pulmonary hypertension. Common operations include anatomic and nonanatomic resections, pleurodesis and lung transplants. Though records of lung surgery date back to the Classical Age, new techniques such as VATS continue to be developed.
The black pleura sign is a radiological feature observed in pulmonary alveolar microlithiasis (PAM), a rare lung disorder characterized by the accumulation of tiny calcium phosphate deposits, known as microliths, within the alveoli. This sign appears as a thin, dark (lucent) line beneath the ribs on imaging studies, contrasting with the diffusely dense, calcified lung parenchyma.
References
- ↑ Kattan, K. R.; Eyler, W. R.; Felson, B. (March 1980). "The juxtaphrenic peak in upper lobe collapse". Radiology. 134 (3): 763–765. doi:10.1148/radiology.134.3.7355230. ISSN 0033-8419. PMID 7355230 . Retrieved 14 July 2021.
- 1 2 Kumaresh, Athiyappan; Kumar, Mitesh; Dev, Bhawna; Gorantla, Rajani; Sai, PM Venkata; Thanasekaraan, Vijayalakshmi (31 July 2015). "Back to Basics – 'Must Know' Classical Signs in Thoracic Radiology". Journal of Clinical Imaging Science. 5: 43. doi: 10.4103/2156-7514.161977 . ISSN 2156-7514. PMC 4541161 . PMID 26312141.
- ↑ Cameron, D. C. (November 1993). "The juxtaphrenic peak (Katten's sign) is produced by rotation of an inferior accessory fissure". Australasian Radiology. 37 (4): 332–335. doi:10.1111/j.1440-1673.1993.tb00091.x. ISSN 0004-8461. PMID 8257331 . Retrieved 14 July 2021.
- ↑ Davis, S. D.; Yankelevitz, D. F.; Wand, A.; Chiarella, D. A. (January 1996). "Juxtaphrenic peak in upper and middle lobe volume loss: assessment with CT". Radiology. 198 (1): 143–149. doi:10.1148/radiology.198.1.8539368. PMID 8539368.
- ↑ Konen, E.; Rozenman, J.; Simansky, D. A.; Yellin, A.; Greenberg, I.; Konen, O.; Hertz, M.; Itzchak, Y. (October 2001). "Prevalence of the juxtaphrenic peak after upper lobectomy". AJR. American Journal of Roentgenology. 177 (4): 869–873. doi:10.2214/ajr.177.4.1770869. ISSN 0361-803X. PMID 11566691 . Retrieved 14 July 2021.