In human anatomy

Human anatomy

Human anatomy is primarily the scientific study of the morphology of the human body. Anatomy is subdivided into gross anatomy and microscopic anatomy. Gross anatomy is the study of anatomical structures that can be seen by the naked eye...

, an azygos lobe is a rare congenital variation of the upper lobe of the right lung

Human lung

The human lungs are the organs of respiration in humans. Humans have two lungs, with the left being divided into two lobes and the right into three lobes. Together, the lungs contain approximately of airways and 300 to 500 million alveoli, having a total surface area of about in...

. Embryologically

Embryology

Embryology is a science which is about the development of an embryo from the fertilization of the ovum to the fetus stage...

, it arises from an anomalous lateral

Anatomical terms of location

Standard anatomical terms of location are designations employed in science that deal with the anatomy of animals to avoid ambiguities that might otherwise arise. They are not language-specific, and thus require no translation...

 course of the azygos vein

Azygos vein

The azygos vein is a vein running up the right side of the thoracic vertebral column. It can also provide an alternate path for blood to the right atrium by allowing the blood to flow between the venae cavae when one vena cava is blocked.-Structure:...

 http://www.ajronline.org/cgi/reprint/156/5/931 http://www.ajronline.org/cgi/content/full/182/5/1139?ijkey=f810fd0909cbafb8976dd77eabd9657a3ff2fe3b&keytype2=tf_ipsecsha in a pleural septum within the upper lobe. As it has no bronchi

Bronchus

A bronchus is a passage of airway in the respiratory tract that conducts air into the lungs. The bronchus branches into smaller tubes, which in turn become bronchioles....

, vein

Vein

In the circulatory system, veins are blood vessels that carry blood towards the heart. Most veins carry deoxygenated blood from the tissues back to the heart; exceptions are the pulmonary and umbilical veins, both of which carry oxygenated blood to the heart...

s and arteries

Artery

Arteries are blood vessels that carry blood away from the heart. This blood is normally oxygenated, exceptions made for the pulmonary and umbilical arteries....

 of its own, it is not a true, or even accessory, pulmonary lobe, but rather an anatomically separated part of the upper lobe. It is usually an incidental finding on chest x-ray

Chest X-ray

In medicine, a chest radiograph, commonly called a chest X-ray , is a projection radiograph of the chest used to diagnose conditions affecting the chest, its contents, and nearby structures...

 or computed tomography

Computed tomography

X-ray computed tomography or Computer tomography , is a medical imaging method employing tomography created by computer processing...

 and is as such not associated with any morbidity but can cause technical problems in thoracoscopic

Thoracoscopy

Thoracoscopy is a medical procedure involving internal examination, biopsy, and/or resection of disease or masses within the pleural cavity and thoracic cavity...

procedures http://www3.interscience.wiley.com/journal/119950409/abstract?CRETRY=1&SRETRY=0.