Azygos fissure, vein, and lobe

AZYGOUS FISSURE, VEIN AND LOBE

1. AZYGOS FISSURE, VEIN, AND LOBE An azygos lobe is created when a laterally displaced azygous vein makes a deep fissure in the upper part of the lung during embryological development. It is therefore not a true accessory lobe, but rather a normal variant appearance of the right upper lobe, which results from   invagination of the azygos vein.

2. AZYGOS FISSURE, VEIN, AND LOBE Azygos fissure represents one of the accessory fissures of lung, which is a normal developmental variant. It is of no clinical significance to the patient. The fissure creates an accessory lobe ( azygos lobe) of the lung.

3. AZYGOS FISSURE, VEIN, AND LOBE Azygos lobe is usually well seen on the chest radiograph, where it is limited by azygous fissure - a fine, convex (relative to the mediastinum ) line that crosses the apex of the right lung.

4. AZYGOS FISSURE, VEIN, AND LOBE Azygos vein, which is lined by visceral and parietal pleura, lies in the base of fissure. Medially there is a small connection of the ' azygos lobe' with the rest of the upper lobe.

5. AZYGOS FISSURE, VEIN, AND LOBE Azygos fissure has a tadpole shape, the azygos vein itself forming head of tadpole. Because azygos vein is a right-sided structure, this accessory fissure is only ever seen on the right side of the chest.

6. AZYGOS FISSURE, VEIN, AND LOBE A lobe of the azygos vein appears in the right lung in about 1 percent of people. It develops when the apical bronchus grows superiorly medial to the arch of the azygos vein instead of lateral to it. As a result, the azygos vein comes to lie at the bottom of a deep fissure in the superior lobe of the right lung. Therefore, the azygos fissure contains four layers of pleura.