Cxr and ct chest appearances of an azygos fissure requiring no additional follow up. The lobe is encountered mostly in the right lung but a few. There is no clinical significance and no treatment is required. This is relatively unusual, as most elements of anatomy reflect bilateral symmetry.
In the present study, an azygos lobe was observed on the right lung of a 56yearold male cadaver. Its pathogenesis is discussed, as are the characteristic xray features that enable an accurate diagnosis. The right azygos lobe is a well recognized entity seen in about 0. As an anatomical variation in 12% of the population, the arch can be displaced laterally, thereby creating a pleural septum separating an azygos lobe from the upper lobe of the right lung.
As an anatomical variation in 12% of the population, the arch can be displaced laterally, thereby. A rare case of an azygos lobe in the right lung of a 40yearold. Six patients with migrating azygos vein were studied by mdct before and after migration. Its radiological aspects are well known but there are few anatomical reports about its bronchial and vascular components. Case report two cases of azygos lobe with normal and. Less frequently, complete disappearance of the fissure has been described named vanishing azygos lobe, afte obliteration of the right upper lung 2. The first one refers to lines such as scars, walls of bulae. Azygos lobe al is a rare normal anatomic variant of the lung with a frequent location at the right upper lobe. The authors describe the characteristic features in a particular case of the azygos lobe observed in the right lung after studying a fresh specimen and doing a. On chest radiographs, azygos fissure azygos fissure in figure 1 is visible as. The lungs are normally divided into five lobes by three main fissures. Azygos lobe definition of azygos lobe by the free dictionary.
An azygos lobe is created when a laterally displaced azygos vein creates a deep pleural fissure into the apical segment of the right upper lobe during embryological development. Disappearance of the azygos lobe vanishing azygos lobe occurred in one patient with a type c lobe. Get a printable copy pdf file of the complete article 979k, or click on a page image below to browse page by page. An azygos lobe is one of, if not the most commmonest, anatomical variants observed on plain chest xray. The azygos vein, which is lined by visceral and parietal pleura, lies in the base of the fissure. Once again, during the operation for primary repair of the esophageal. An enlarged azygos vein traversing an azygos lobe reveals a. This arch of the azygos vein arcus venae azygos is an important anatomic landmark. Learning radiology central, venous, catheter, azygos, vein. The azygos lobe is a rare anatomical variant, most often encountered in the right lung. In human anatomy, an azygos lobe is a normal anatomical variation of the upper lobe of the right lung. There are other applications of azygos even in human anatomy, quite. Axial a and sagital reformatted chest ct b, reconstructed in.
It should not be mistaken for an abnormality like a pneumothorax or bulla azygos lobe. We explored the prevalence of an azygos lobe using computed tomography at our. Pdf prevalence of an azygos lobe using thoracic computed. Although an azygos lobe is a rare anomaly of the lung, its radiological appearance has been well defined. Clinically, the azygos lobe has been accepted as a normal variation that can simulate various diseases. The patient had undergone interstitial brachytherapy for a tumor of the right upper lung. Cureus a rare case of an azygos lobe in the right lung.
Azygos pseudo lobe is not a true lobe, does not have separate broncus or vasculature, due to invagination of azygos vein, no clinical significance. At its base is the azygos vein which can be seen as a teardropshaped structure. It is a normal anatomic variant of the right upper lobe due to invagination of the azygos vein and pleura during development in the fetus. Lobe of azygos vein definition of lobe of azygos vein by. An azygos fissure has a tadpole shape, the azygos vein itself forming the head of the tadpole. The azygos lobe is a rare anomaly in bronchopulmonary segmentation due to an unusual course of the azygos vein. The azygos vein, in this case, is found passing along the bottom of the fissure and is suspended from the thoracic wall through a fold of the. Media in category human anatomy, azygos lobe the following 22 files are in this category, out of 22 total. In approximately 2% of the population, the arch of the azygos vein which courses over the right main bronchus, can be part of a pleural septum producing the azygos lobe, which is separate from the right upper lobe. Once again, during the operation for primary repair of the esophageal atresia, difficulties arose in reflecting the pleura. In approximately 2% of the population, the arch of the azygos vein which courses over the right main bronchus, can be part of a pleural septum producing the azygos lobe, which is separate. The patient had undergone interstitial brachytherapy for a tumor of the right upper lung, with implantation of palladium103 seeds that migrated and occluded the arteries of this lung segment. In conclusion, in case of an azygos lobe, the azygos vein may displace out of its fissure, secondary to lung collapse.
An empty azygos fissure must therefore suggest a history of pulmonary atelectasis related to pneumothorax or large effusion. Hemiazygos and accessory azygos veins may communicate witheach other. We found azygos lob incidentally on chest xray and computed axial tomography of chest. The video will show an azygos lobe on a chest xray pa view. The tearshaper azygos vein is seen at the base of the fissure. May 02, 2008 the azygos lobe is a lobe of the lung that is extra.
The azygos lobe is a normal variant that is found in 1% of anatomic specimens and on about 0. A chest ct with contrast showing the azygous fissure in the right upper lobe. The azygos lobe azygos lobe in figures 1 and and2 2 is a uncommon anomaly that is found in 1% of anatomic specimens, 1 on about 0. A rounded projection, especially a rounded, projecting anatomical part.
On chest radiograph, azygos lobe can be seen as a curvilinear line of the right apex separating the apical right upper lung. It is found in under 1% of the population and is of no clinical significance. Because of the clinical importance and rare occurrence, this anomaly was compared and discussed. It is usually detected using a chest xray, but computed tomography can also be used in selected cases for advanced examination and differential diagnosis. The prevalence and dimensions of the azygos lobe were determined with a 95% confidence interval. The author could find only 11 cases that have been previously reported in the world literature. Fuad aa, mubarak my two cases of azygos lobe with normal and aneurysmal azygos vein on computed tomography.
Preoperative awareness of a migrating azygos vein may also be useful before thoracic surgery. It is usually asymptomatic and does not require a specific treatment, but it should be. The azygos lobe is a congenital variant with an incidence of about 0. Instead, the vein penetrates the lung carrying along pleural layers that entrap a portion of the right upper lobe. It is due to invagination of the azygos vein and pleura during. Azygos definition of azygos by the free dictionary. Because the azygos vein is a rightsided structure, this. Oct 28, 2011 the azygos lobe is a rare anomaly in bronchopulmonary segmentation due to an unusual course of the azygos vein. Azygos lobe which appears in the inner surface of the right lung apex is a rare venous anomaly of the lung.
Azygos lobe definition of azygos lobe by medical dictionary. Azygos lobe in a south african cadaveric population. However, on chest roentgenograms, this anomaly may appear to be present if there are any other pathological conditions. The azygos lobe is a rare anomaly of the lung that is separated from the rest of the upper lobe by an azygos fissure.
Clinically, the azygos lobe has been accepted as a normal variation that. A total of 704 adult cadavers dissected over a tenyear period by students in the department of human anatomy at the medunsa campus, university of limpopo, were studied. Background an azygos lobe of the lung is a rare congenital venous malformation. Full text full text is available as a scanned copy of the original print version. An azygos lobe forms when the right posterior cardinal vein, one of the precursors of the azygos vein, fails to migrate over the apex of the lung and penetrates it instead, carrying along two pleural layers that invaginates into the upper portion of the right upper.
Dec, 2009 the video will show an azygos lobe on a chest xray pa view. In contrast to other accessory lobes, the azygos lobe does not correspond to a distinct anatomical. An enlarged azygos vein traversing an azygos lobe reveals a connection between the inferior vena cava and. The right azygos lobe is supplied by the medial segments of the apical and anterior or posterior branches of the apical segmental bronchial artery and vein. These images have typical appearance of azygos lobe, fissure and. An azygos lobe is an accessory lobe of the lung that may occasionally be confused with a pathological process such as a bulla, lung abscess or neoplasm. Pdf an enlarged azygos vein traversing an azygos lobe reveals a. Azygos lobe is an accessory lobe at the right apex that frequently presents as an incidental finding. The lobe is encountered mostly in the right lung but a few cases have also been described in the left lung. Pdf we report a rare case where the inferior vena cava connected to the azygos vein, a diagnosis triggered by observation of an enlarged. Learn vocabulary, terms, and more with flashcards, games, and other study tools. Azygos vein the azygos vein is a unilateral vessel that ascends in the.
Superior vena cava a large vein, the azygos, which receives oxygenpoor blood from the chest wall and the bronchi, opens into the. The azygos vein had an abnormal anterior loop and entered the anterior surface of the right upper lobe. A small lobe sometimes found on the upper part of the right lung, formed by an infolding of the pleura and separated from the rest of the upper lobe by a deep groove lodging the azygos vein. Because of the clinical importance and rare occurrence, this anomaly was compared and. In those with an azygos fissure, the azygos vein will no longer be visible at its normal position at the junction of the trachea and right main bronchus. So, the detection of this anomaly and clarification of its precise.
It occurs when the right posterior cardinal vein, one of the precursors of the azygos vein, fails to migrate over the apex of the lung and penetrates it instead, carrying along pleural layers that entrap a portion of the right upper lobe. May 11, 2020 the azygos venous system is located on. The azygos fissure white arrows demarcates the lateral boundary of the azygos lobe, part of the right upper lobe. Ultimately the catalyst leading to the decision being made for streptomycin treatment to be commenced appears to be the fact that in june 1948 a swelling over the lower dorsal spine is identified and it is apparent that the tuberculous infection has spread further. In human anatomy, an azygos lobe is a normal anatomical variation of the upper. Here, we describe a rare case of an azygos lobe of the right lung, diagnosed incidentally on a computed tomography ct scan in a 40yearold male patient who presented with chest pain, shortness of. A cadaver with azygos lobe and its clinical significance. Miliary spread is a pathological process involving the widespread dissemination of the tubercle bacilli but the. Azygos lobe article about azygos lobe by the free dictionary. Embryologically, it arises from an anomalous lateral course of the azygos vein 1 in a pleural. Its etiology is related to a defect of the migration of the azygos vein during the embryonic development. The lobes are the portions of the lung and the fissures are the plains that divide different lobes. Pdf migrating azygos vein and vanishing azygos lobe. May 11, 2020 the azygos venous system is located on either side of the vertebral column and drains the viscera within the mediastinum, as well as the back and thoracoabdominal walls.
It is not a true accessory lobe as it does not have its own bronchus. Occasionally, invaginations of the visceral pleura create accessory fissures that separate individual bronchopulmonary segments into accessory lobes. An azygos lobe is found in 1% of anatomical specimens 2 and is twice as common in males than females 3 embryology. An azygos lobe is created when a laterally displaced azygos vein makes a deep pleural fissure into the apical segment of the right upper lobe during embryological development. Objective the purpose of this study was to describe six cases of migrating azygos vein and to explain the etiologic factors that contribute to the migration. There are other applications of azygos even in human anatomy, quite esoteric ones, rarely encountered. Right azygos lobe occurring with fissural and lobation. In each case, the shape of the azygos lobe was classified according to. An azygos lobe is found in 1% of anatomic specimens and forms when the right posterior cardinal vein, one of the precursors of the azygos vein, fails to migrate over the apex of the lung 1. Its counterparts on the left side are the hemiazygos and accessory hemiazygos veins. All patients had repeated episodes of cough, vomiting, and a short mesoazygos. Cureus a rare case of an azygos lobe in the right lung of a. Compare the radiographic findings before c and after d therapy. An azygos lobe is observed in highresolution computed tomography images by 1.
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